WO2019013591A1 - Battery module - Google Patents

Battery module Download PDF

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Publication number
WO2019013591A1
WO2019013591A1 PCT/KR2018/007986 KR2018007986W WO2019013591A1 WO 2019013591 A1 WO2019013591 A1 WO 2019013591A1 KR 2018007986 W KR2018007986 W KR 2018007986W WO 2019013591 A1 WO2019013591 A1 WO 2019013591A1
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WO
WIPO (PCT)
Prior art keywords
welding
electrode lead
bus bar
electrode
electrode leads
Prior art date
Application number
PCT/KR2018/007986
Other languages
French (fr)
Korean (ko)
Inventor
최항준
윤한종
이강일
Original Assignee
주식회사 엘지화학
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from KR1020180081313A external-priority patent/KR102144945B1/en
Application filed by 주식회사 엘지화학 filed Critical 주식회사 엘지화학
Priority to CN201880005614.5A priority Critical patent/CN110140235B/en
Priority to US16/345,862 priority patent/US11011804B2/en
Priority to EP18832083.2A priority patent/EP3654411B1/en
Priority to JP2019548854A priority patent/JP7027634B2/en
Priority to PL18832083.2T priority patent/PL3654411T3/en
Publication of WO2019013591A1 publication Critical patent/WO2019013591A1/en

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/50—Current conducting connections for cells or batteries
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/20—Bonding
    • B23K26/21—Bonding by welding
    • B23K26/22—Spot welding
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/204—Racks, modules or packs for multiple batteries or multiple cells
    • H01M50/207—Racks, modules or packs for multiple batteries or multiple cells characterised by their shape
    • H01M50/211—Racks, modules or packs for multiple batteries or multiple cells characterised by their shape adapted for pouch cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/50—Current conducting connections for cells or batteries
    • H01M50/569—Constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present invention relates to a battery module, and more particularly, to a battery module having improved weldability of an electrical connection structure, a battery pack including the battery module, and an automobile.
  • the secondary rechargeable batteries are nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries.
  • lithium secondary batteries have almost no memory effect compared to nickel- It is very popular because of its low self-discharge rate and high energy density.
  • the lithium secondary batteries mainly use a lithium-based oxide and a carbonaceous material as a cathode active material and an anode active material, respectively.
  • the lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate each coated with such a positive electrode active material and a negative electrode active material are disposed with a separator interposed therebetween, and an outer casing, that is, a battery case, for sealingly storing the electrode assembly together with the electrolyte solution.
  • a lithium secondary battery can be classified into a can type secondary battery in which an electrode assembly is embedded in a metal can, and a pouch type secondary battery in which an electrode assembly is embedded in a pouch of an aluminum laminate sheet, depending on the shape of the casing.
  • secondary batteries are widely used not only in small-sized devices such as portable electronic devices, but also in medium to large-sized devices such as automobiles and electric power storage devices.
  • carbon energy is getting depleted and the interest in the environment is increasing, attention is focused on hybrid cars and electric cars worldwide, including the US, Europe, Japan, and Korea.
  • the most important components in such hybrid vehicles and electric vehicles are battery packs that give drive power to vehicle motors. Since hybrid vehicles and electric vehicles can obtain the driving force of the vehicle through charging and discharging of the battery pack, the fuel efficiency is higher than that of the vehicle using only the engine, and the users are increasingly increasing in terms of not discharging or reducing pollutants. to be.
  • Most battery packs particularly medium- to large-sized battery packs such as hybrid cars, electric vehicles and Energy Storage Systems (ESS), include a plurality of secondary batteries, which are connected in series and / So that the output is improved.
  • pouch-type secondary batteries are widely used because they are easy to be stacked, light in weight, and can contain a large number of batteries in a middle- or large-sized battery pack.
  • the electrical connection between the secondary batteries is often constituted by a method of directly contacting the electrode leads with each other.
  • the electrode leads of the same polarity are connected to each other and the electrode leads of the other polarity are connected to each other in order to connect them in series.
  • the bus bar may be bonded to the electrode lead, particularly, to two or more electrode leads. At this time, the connection between the electrode lead and the bus bar is often made by welding.
  • FIG. 1 is a partial perspective view schematically showing a structure in which an electrode lead and a bus bar are welded to each other in a conventional battery module.
  • Fig. 2 is a cross-sectional view taken along the line A1-A1 'in Fig. 1, and is a diagram showing the welded part in a schematic form.
  • cracks when pores or cracks are generated in the welded portion, cracks can be rapidly grown due to external vibration or impact. For example, when a crack occurs at a point A3 in Fig. 1, such a crack can be rapidly enlarged along the direction of the arrow A4, that is, along the length direction of the welding line, by vibration or impact.
  • the direction in which the external force is applied may be a direction perpendicular to the welding line (left and right direction in FIG. 1).
  • the cross-sectional area of the welded portion in the direction in which the external force is applied is low, .
  • cracks often start from the end of the welding line. These cracks may continue to grow along the weld line.
  • the welding strength at any one end can be reduced.
  • welding may be performed in such a manner that the laser is continuously irradiated from one end of the welding line to the other end. In the portion where welding starts, sufficient heat is not transferred to the electrode lead, There may be a problem of falling.
  • the weldability is poor, and particularly, it is vulnerable to vibration and impact. Furthermore, when the battery module is applied to an automobile, it may be exposed to a large and large vibration or shock, and therefore it is necessary that the weldability for the connection of the electrode lead and / or the bus bar is stably secured.
  • a battery module comprising: a cell assembly including a plurality of secondary cells stacked in at least one direction and each having an electrode lead, the plurality of secondary cells being electrically connected through the electrode leads; And at least one electrode lead formed of an electrically conductive material and electrically connected to the electrode lead of the secondary battery, wherein at least one of the electrode leads includes at least one of the other electrode leads and the contacted bus bars, As shown in Fig.
  • the welding spot may be configured to have a plurality of spiral welding lines.
  • the welding spot may be configured such that the plurality of welding lines have the same rotational direction as each other, and at least a part of one welding line is inserted between the other welding lines.
  • the welding spot may be configured such that a straight line connecting each inner end of the plurality of welding lines and a straight line connecting the respective outer ends are parallel to each other.
  • the welding spot may be configured so that the inner ends of the plurality of welding lines are connected to each other.
  • a plurality of welding spots may be provided for one electrode lead.
  • a plurality of welding spots provided in one electrode lead can be configured so that the outer end thereof is positioned on one straight line.
  • the welding spot may be configured to weld a plurality of mutually stacked electrode leads and one bus bar.
  • the electrode lead may have a concave portion formed concavely inwardly, and the welding spot may be configured such that at least a part of the welding spot is located in the concave portion.
  • a battery pack including a battery module according to the present invention.
  • an automobile including the battery module according to the present invention.
  • the weldability between the electrode leads and / or between the electrode leads and the bus bar is improved, and the welding strength can be improved.
  • the welding area can be increased in the direction in which such force acts have. Therefore, according to this aspect of the present invention, tensile strength can be improved between the electrode leads and / or between the electrode leads and the bus bars.
  • the welding area increases between the electrode leads and / or between the electrode leads and the bus bar, so that the tensile strength of the welding portion can be improved.
  • the welding state of the electrical connection structure can be stably maintained.
  • FIG. 1 is a partial perspective view schematically showing a structure in which an electrode lead and a bus bar are welded to each other in a conventional battery module.
  • Fig. 2 is a cross-sectional view taken along the line A1-A1 'in Fig. 1, and is a diagram showing the welded part in a schematic form.
  • FIG. 3 is a perspective view schematically showing a configuration of a battery module according to an embodiment of the present invention.
  • FIG. 4 is a front view of the configuration of a battery module according to an embodiment of the present invention.
  • FIG. 5 is a view schematically showing a configuration of a welding spot applied to an electrode lead of a battery module according to the present invention.
  • FIG. 6 is a diagram schematically illustrating a tornado shape of a welding spot according to another embodiment of the present invention.
  • FIG. 7 is a schematic representation of a tornado shape of a weld spot in accordance with another embodiment of the present invention.
  • FIG. 8 is a view schematically showing a configuration of a plurality of welding spots provided in an electrode lead in a battery module according to an embodiment of the present invention.
  • FIG. 9 is a cross-sectional view schematically showing a welding configuration between an electrode lead and a bus bar in a battery module according to an embodiment of the present invention.
  • FIG. 10 is a cross-sectional view schematically showing a welding configuration of an electrode lead and a bus bar according to another embodiment of the present invention.
  • FIG. 11 is a view schematically showing a configuration of a welding spot according to another embodiment of the present invention.
  • FIG. 12 is a view schematically showing the configuration of a welding spot according to another embodiment of the present invention.
  • FIG. 13 is a view schematically showing a configuration of a welding spot according to another embodiment of the present invention.
  • FIG. 14 is a view schematically showing a welding configuration of an electrode lead and a bus bar according to an embodiment of the present invention.
  • Fig. 15 is a view showing tensile strength measurement results for various examples and comparative samples of the present invention.
  • 16 is a view schematically showing a welding configuration of an electrode lead according to another embodiment of the present invention.
  • 17 is a view showing tensile strength measurement results of various other embodiments of the present invention.
  • FIG. 18 is an image of the peeling according to the tensile strength measurement according to one embodiment of the present invention.
  • Fig. 19 is an image of the peeling test according to the tensile strength measurement according to another embodiment of the present invention.
  • 20 is a view showing the interval between the electrode lead and the bus bar applied to various embodiments of the present invention and a comparative sample.
  • Fig. 21 is a diagram showing the result of defect measurement observed visually with respect to various examples and comparative samples of Fig. 20; Fig.
  • Fig. 22 is a view showing tensile strength measurement results for various examples and comparative samples of Fig. 20; Fig.
  • FIG. 23 is a view schematically showing a configuration of a plurality of welding spots provided in an electrode lead in a battery module according to another embodiment of the present invention.
  • FIG. 3 is a perspective view schematically showing a configuration of a battery module according to an embodiment of the present invention.
  • 4 is a front view of the configuration of a battery module according to an embodiment of the present invention.
  • the battery module according to the present invention may include a cell assembly 100 and a bus bar 200.
  • the cell assembly 100 may include a plurality of secondary batteries 110.
  • the cell assembly 100 may include a plurality of pouch-type secondary batteries as the secondary batteries 110.
  • the pouch-type secondary battery 110 may include an electrode assembly, an electrolyte, and a pouch exterior member.
  • the electrode assembly may be configured such that at least one positive electrode plate and at least one negative electrode plate are disposed with the separator interposed therebetween. More specifically, the electrode assembly can be divided into a winding type in which one positive electrode plate and one negative electrode plate are wound together with a separator, and a stacked type in which a plurality of positive electrode plates and a plurality of negative electrode plates are alternately stacked with a separator interposed therebetween .
  • the pouch exterior member may be configured in the form of an external insulating layer, a metal layer, and an internal adhesive layer. More specifically, such a pouch case is provided with a metal thin film (metal layer), such as an aluminum thin film, for protecting internal components such as an electrode assembly and an electrolytic solution, complementing the electrochemical properties of the electrode assembly and electrolyte, And can be configured to be included.
  • a metal thin film such as an aluminum thin film
  • An insulating layer, an inner adhesive layer In order to ensure electrical insulation between the internal components of the secondary battery 110 such as the electrode assembly and the electrolytic solution and other components outside the secondary battery 110, An insulating layer, an inner adhesive layer).
  • the pouch exterior member can be composed of two pouches, and at least one of them can be formed with a concave internal space.
  • the electrode assembly can be housed in the inner space of the pouch.
  • a sealing portion is provided on the outer circumferential surface of the two pouches, and these sealing portions are fusion-bonded to each other, so that the inner space accommodating the electrode assembly can be sealed.
  • the battery module according to one aspect of the present invention may employ various types of pouch-type secondary batteries known at the time of filing of the present invention. Therefore, detailed description of the internal structure of the secondary battery 110 provided in the cell assembly 100 will be omitted.
  • the plurality of pouch-shaped secondary batteries 110 may be stacked in at least one direction, for example, the lateral direction (Y-axis direction in the figure) as shown in the figure.
  • each of the pouch-shaped secondary batteries 110 has a shape erected in a vertical direction (Z-axis direction in the drawing) with respect to the sheet surface (XY plane in the figure), that is, a shape in which the large surface faces right and left, . ≪ / RTI >
  • each of the secondary batteries 110 can be arranged such that the large surfaces face each other.
  • the side where the electrode lead 111 is seen is referred to as the front side of the battery module. From the viewpoint of the front side, the upper, lower, left, right, front , And the back direction.
  • Each of the secondary batteries 110 included in the cell assembly 100 may include an electrode lead 111.
  • the electrode lead 111 includes a positive electrode lead and a negative electrode lead, and can function as an electrode terminal of the secondary battery 110.
  • the electrode leads 111 are formed in a plate-like shape and can protrude to the outside of the pouch outer casing.
  • the electrode leads of each secondary battery 110 are disposed in front of the cell assembly 100 (in the -X-axis direction in the drawing) from at least one of the front end portion and the rear end portion of the cell assembly 100, Or in the rear (in the + X-axis direction in the drawing).
  • the electrode lead 111 may be made of a metal such as aluminum or copper to function as a terminal of a battery.
  • the electrode leads 111 may be formed in various thicknesses.
  • the electrode lead 111 may have a thickness of 0.1 mm to 1 mm. More specifically, the electrode lead 111 may have a thickness of 0.2 mm to 0.6 mm.
  • the electrode leads 111 can be configured to have various widths.
  • the electrode lead 111 may be configured to have a width of 20 mm to 60 mm.
  • the thickness and the width of the electrode lead 111 may be variously configured according to the specification or the type of the battery or the battery pack.
  • the electrode leads 111 of the secondary battery 110 may be connected to each other to be electrically connected to each other.
  • a plurality of secondary batteries can be connected to each other in series or in parallel by direct contact of the electrode leads.
  • the plurality of secondary cells may be connected to each other in series or in parallel by indirectly connecting the electrode leads through the bus bar 200.
  • the bus bar 200 may be electrically connected to an electrode lead of a secondary battery in contact with an electrode lead of the secondary battery.
  • the bus bar 200 is electrically connected to two or more electrode leads, thereby electrically connecting the electrode leads to each other.
  • the bus bar 200 is directly connected to at least one of the electrode leads to measure electrical characteristics at the electrode lead side.
  • the bus bar 200 may sense voltage across one or more secondary batteries.
  • the bus bar 200 may be formed of an electrically conductive material to be electrically connected to the electrode lead 111 of the secondary battery.
  • the bus bar 200 may be made of a metal such as copper or aluminum.
  • the bus bar 200 may be formed in the form of a plate (plate) or rod similar to the electrode lead 111. At this time, the bus bar 200 may be formed to have a thicker thickness than the electrode lead 111.
  • the bus bar 200 may be configured to have a thickness of 0.3 mm to 4 mm.
  • a thickness of the bus bar 200 is 0.6 mm or less when the thickness of the electrode lead 111 is 0.2 mm to 0.4 mm.
  • Lt; RTI ID 0.0 > mm. ≪ / RTI >
  • the thickness of such a bus bar may be variously configured according to the specification or kind of the battery or the battery pack, and the present invention is not limited to the specific thickness of the bus bar.
  • the electrode leads 111 provided in each secondary battery 110 of the cell assembly 100 can be coupled and fixed to the bus bar 200.
  • the electrode lead 111 of the secondary battery included in the cell assembly 100 can be coupled and fixed to another electrode lead 111, that is, the electrode lead 111 of another secondary battery provided in the cell assembly 100 have.
  • between the electrode lead 111 and the bus bar 200 and / or between the electrode lead 111 and the electrode lead 111 can be fixed to each other by welding.
  • the welding at this time can be performed by a laser welding method in which the laser is irradiated and the workpiece is welded. That is, the space between the electrode leads 111 and the electrode leads 111 and / or between the electrode leads 111 and the bus bars 200 may be laser-welded.
  • the electrode leads 111 of the plurality of secondary batteries included in the cell assembly 100 may be in contact with the other electrode leads 111 or in contact with the bus bar 200.
  • At least one electrode lead 111 of the plurality of electrode leads provided in the cell assembly 100 is welded to at least one of the other electrode leads 111 and the contacted bus bars 200, They can be fixed to each other by the spots W.
  • the electrode leads 111 when two or more electrode leads 111 are laminated in face-to-face contact with each other, the electrode leads 111 which are in contact with each other can be fixedly coupled to each other by the welding spot W.
  • the electrode lead 111 and the bus bar 200 can be coupled and fixed to each other by the welding spot W have.
  • the welding spot W at this time may be formed in a tornado shape. Such a tornado-shaped welding spot W configuration will be described in more detail with reference to Fig.
  • FIG. 5 is a view schematically showing a configuration of a welding spot applied to an electrode lead of a battery module according to the present invention.
  • FIG. 5 is an enlarged view of the portion B1 in FIG.
  • the welding spot W applied to the electrode lead may be configured in the form of a tornado.
  • the welding line is a path irradiated with a laser having an energy of a predetermined power or more, and the workpiece can be welded to each other around the welding line.
  • the welding line may be formed in a curved shape rather than a straight line, and moreover, the curved shape may be formed in a whirl-like shape. That is, the welding line may be configured such that at least a part of the welding line rotates in a clockwise or counterclockwise direction and moves from the outer side to the central side of the welding spot W. That is, the welding line may be configured to draw a circle whose diameter gradually decreases.
  • the welding line may be formed in such a manner that the laser irradiation path moves from the outside to the inside (center) direction or from the inside to the outside.
  • the welding spot W to be welded between the electrode lead and the electrode lead, and / or between the electrode lead and the bus bar can be configured in the form of a tornado.
  • welding strength between the electrode to be welded that is, between the electrode lead and the electrode lead, and / or between the electrode lead and the bus bar can be improved.
  • the welding portion can be formed uniformly and widely. Therefore, the welding portion can be stably maintained even in vibration or shock in various directions.
  • the welding spot W applied to the electrode lead 111 and / or the bus bar 200 may be configured to have a plurality of welding lines formed in a spiral shape. have.
  • one weld spot W may be configured with two weld lines, a first weld line denoted W1 and a second weld line denoted W2 .
  • the first welding line W1 and the second welding line W2 may have different outer ends. 5
  • the outer end o1 of the first welding line W1 indicated by o1 and the outer end of the second welding line W2 indicated by o2 are formed separately and at different positions Can be located.
  • a plurality of different spirals such as two spirals, are configured to form one tornado, that is, one welding spot.
  • the inner ends of the respective spirals can be located at different positions. 5
  • an inner end i1 of the first welding line W1 and an inner end i2 of the second welding line W2 are located at the center of the welding spot W
  • the two inner ends i1 and i2 may be configured as separate from each other. In this case, it can be said that the first welding line W1 and the second welding line W2 are separated from each other without being connected to each other.
  • the welding spot W may be configured such that a plurality of welding lines constituting the welding spot W have the same rotational direction.
  • the two welding lines that is, the first welding line W1 and the second welding line W2 may both be configured to rotate so that the inside direction is clockwise have.
  • At this time, at least a part of one welding line can be configured in a form inserted between different welding lines.
  • the first welding line W1 may be configured such that a portion thereof is inserted between the second welding lines W2.
  • the welding configuration in which the plurality of spiral-shaped welding lines form one welding spot W, that is, one tornado, one welding line in the form of a spiral forms a welding spot
  • the welding performance can be further improved as compared with the welding configuration comprising
  • the welding strength of the outer or inner side of the welding spot may be somewhat lower .
  • a laser irradiation path is formed from the outer end o1 to the inner end i1 of the first welding line W1
  • the welding depth can not be sufficiently formed and the welding strength may be lower than the inside end i1.
  • a welding spot W configured in the form of a tornado
  • the interval of each welding line the diameter of the welding spot, the number of turns of the spiral, the distance between the inner ends, Or the material, the number and shape of the weld spots, and the like.
  • the spacing of the weld lines constituting the tornado may be comprised between 0.002 mm and 0.006 mm. More specifically, the distance between the first welding line W1 and the second welding line W2 may be comprised between 0.003 mm and 0.004 mm.
  • the diameter of the weld spot such as the maximum width of the tornado, may be comprised between 1.5 mm and 3 mm. 5
  • the distance between the outer end o1 of the first welding line W1 and the outer end o2 of the second welding line W2 may be comprised between 2.0 mm and 2.5 mm .
  • the medial end-to-end distance in one tornado may be comprised between 0.15 mm and 0.25 mm. More specifically, in the configuration of Fig. 5, the distance between the inner end i1 of the first welding line W1 and the inner end i2 of the second welding line W2 may be 0.2 mm. According to such a configuration, it is possible to prevent a crack from being generated in the welded portion due to over-welding in the vicinity of the inner end portion or deterioration of the welding force due to the weak welding.
  • At least some of the parameters may be configured to be dependent on the setting values of the other parameters.
  • the spacing of the weld lines may be 0.0035 mm or more and 0.0045 mm or less.
  • the interval of the welding line at this time may be 0.004 mm.
  • the welding strength may be lowered due to over-welding.
  • the interval of the welding line is 0.005 mm, weak welding phenomenon may occur.
  • the interval of the welding line may be 0.0025 mm or more and 0.0035 mm or less.
  • the interval of the welding line at this time may be 0.003 mm. If, in such a diameter tornado configuration, the spacing of the weld lines is 0.004 mm, there may be a bus bar weld failure due to weak welding. On the contrary, in the case of a tornado configuration having such a diameter, when the interval of the welding lines is 0.002 mm, the welding strength may be lowered due to over-contact.
  • the thicknesses of the two lines are different from each other. However, It does not mean that the weld thickness of the two lines should be different.
  • each of the outer ends, i.e., the plurality of outer ends, of the plurality of welding lines are positioned opposite to each other with respect to one center line Lt; / RTI >
  • the weld spot can be divided into four quadrants based on the center point p of the weld spot W.
  • the center point p of the weld spot W is a point located at the center of the weld spot W, for example, the distance between o1 and o2, which is the outer end of the two weld lines, It is the center point of the circle.
  • two straight lines perpendicular to each other can be drawn, passing through the center point p of the weld spot W. For example, a straight line passing through the center point p in parallel with the Y axis in Fig.
  • a region located at the right upper end by the two straight lines c11 and c12 is referred to as a first quadrant Q1
  • a region located at the upper left end is referred to as a second quadrant Q2
  • the region located at the lower left corner is referred to as the third quadrant Q3
  • the region located at the lower right corner may be referred to as the fourth quadrant Q4.
  • the outer end o1 of the first welding line W1 and the outer end o2 of the second welding line W2 are located in different quadrants . ≪ / RTI >
  • the outer end o1 of the first welding line W1 and the outer end o2 of the second welding line W2 may be configured to be located in quadrants that are not adjacent but opposite to each other.
  • the outer end o1 of the first welding line W1 when the outer end o1 of the first welding line W1 is located in the third quadrant Q3, the outer end o2 of the second welding line W2 is located at the second quadrant Q3, Can be configured to be located in the first quadrant (Q1), which is not adjacent to the third quadrant but located on the opposite side from each other. If one of the outer ends of the two welding lines W1, W2, such as o1, is located at the straight line c12, the other outer end, such as o2, may also be located on the straight line c12. However, in this case, the two outer ends o1 and o2 may be located on opposite sides with respect to the straight line c11.
  • the present invention it is possible to further improve the welding strength of the tornado-shaped welding spot W.
  • the fatigue that may occur in the vicinity of the end of one or more weld lines may be distributed rather than being concentrated in a particular portion, thereby further improving the welding performance.
  • the welding spot W may be configured such that a straight line connecting each inner end of the plurality of welding lines and a straight line connecting the respective outer ends are parallel to each other. This will be described in more detail with reference to FIG.
  • FIG. 6 is a diagram schematically illustrating a tornado shape of a welding spot according to another embodiment of the present invention.
  • FIG. 6 is another implementation that can be applied to the portion B1 of FIG.
  • FIG. 6 is another implementation that can be applied to the portion B1 of FIG.
  • the straight line connecting the outer end o1 of the first welding line W1 and the outer end o2 of the second welding line W2 may be c2.
  • the straight line connecting the inner end i1 of the first welding line W1 and the inner end i2 of the second welding line W2 may also be c2.
  • the angle formed by the straight line connecting the outer ends o1 and o2 of the plurality of welding lines and the straight line connecting the inner ends i1 and i2 of the plurality of welding lines is 0, and both straight lines are parallel to each other Lt; / RTI >
  • the straight line connecting the outer ends o1, o2 to the plurality of welding lines and the straight line connecting the inner ends i1, i2 may be the same straight line c2. That is, the tornado can be configured such that both the outer end and the inner end of the plurality of welding lines are located on one straight line.
  • the welding performance can be further improved.
  • the straight line connecting between the outside end and the inside end of the tornado welding spot W is formed vertically in the direction in which the tensile proceeds, the fatigue of the end portion may be lowered.
  • the tensile is mainly formed in the left-right direction
  • the straight lines connecting the outer end and the inner end of the weld spot W are formed in the vertical direction, The stress exerted on the user can be mitigated.
  • each welding line is irradiated with a laser beam in the inner- Or by moving the laser irradiation path from the inner end to the outer end direction.
  • the first welding line W1 and the second welding line W2 are formed in such a manner that the laser is irradiated in the inner end direction from the outer end portion, or in the outer end direction from the inner end portion .
  • the welding line relatively formed first is formed in a form in which the laser is irradiated in the direction from the outer end to the inner end
  • the welding line formed relatively late can be configured in a form in which the laser is irradiated from the inner end to the outer end have.
  • the first welding line W1 is formed prior to the second welding line W2, the first welding line W1 is located at the outer end o1 And the laser irradiation path is moved in the direction of the inner end portion i1.
  • the second welding line W2 may be configured such that the laser irradiation path is moved from the inner end i2 to the outer end o2 as indicated by an arrow d2.
  • the laser irradiation for forming the second welding line W2 is started adjacent to the portion where the laser irradiation for forming the first welding line W1 ends,
  • the laser irradiation time for forming the first welding line W1 and the second welding line W2 can be shortened and the processability can be improved.
  • the welding spot may be configured so that the inner ends of the plurality of welding lines are connected to each other. This will be described in more detail with reference to FIG.
  • FIG. 7 is a schematic representation of a tornado shape of a weld spot in accordance with another embodiment of the present invention.
  • FIG. 7 may be another implementation configuration that may be applied to the portion B1 of FIG.
  • two welding lines W1 and W2 formed in a spiral shape are provided to form one tornado, and two tornadoes can be connected to each other at their inner ends, such as a portion indicated by B4.
  • the first welding line W1 and the second welding line W2 are each formed in a spiral shape and have different outer ends o1 and o2, And can be configured in a connected form.
  • a plurality of the welding spots W are provided for one electrode lead 111.
  • the electrode leads 111 exposed to the outside are located at the rear of the other electrode leads and / or the bus bar 200 and the plurality of welding spots As shown in Fig.
  • the plurality of welding spots W are formed in a tornado shape as described above, and can be arranged to be spaced apart from each other by a predetermined distance.
  • a plurality of welding spots W with respect to one electrode lead can be arranged in the vertical direction (Z-axis direction in the figure). More specifically, when a plurality of secondary batteries are arranged in the lateral direction (the Y-axis direction in the figure), the electrode leads of each secondary battery can be mutually contacted in a laminated form in the front-rear direction . At this time, the contact portion between the electrode lead and the electrode lead and / or between the electrode lead and the bus bar is formed in the vertical direction (Z-axis direction in the figure) and the short side is formed in the horizontal direction , Which is substantially rectangular in shape.
  • the plurality of welding spots may be arranged in the long-side direction, that is, in the vertical direction, in such a rectangular contact portion. That is, the welding spots may be arranged to be spaced a predetermined distance along the longitudinal direction of the front exposed portion of the electrode lead.
  • each of the welding spots is formed in a tornado shape, and not only is the welding performance excellent as it is, but also a plurality of welding spots are spaced apart from each other by a predetermined distance, so that the weldability can be more stably maintained. That is, since a plurality of welding spots are separated from each other, even if a crack or the like occurs in one welding spot W, such a crack is difficult to grow up to another welding spot W. Therefore, the welding state of the electrode leads can be stably maintained. Furthermore, even if the battery module is frequently exposed to vibration or impact, it is possible to prevent the crack from continuing to grow due to such vibration or impact, thereby preventing the occurrence of defective electrical connection of the electrode leads.
  • the applied load is distributed to a plurality of welding spots, so that the welding state of each welding spot can be more stably maintained.
  • the direction in which the force is mainly applied by impact, vibration (Y-axis direction in the figure) that is an arrangement direction.
  • the welding spots are arranged in the vertical direction (the Z-axis direction in the figure) with respect to one electrode lead as in the above-described configuration, a plurality of welding spots are arranged in a direction substantially perpendicular to the direction in which the force is applied.
  • the welding state of a plurality of welding spots with respect to an external force can be more stably maintained.
  • the plurality of welding spots provided in one electrode lead can be configured such that the outer end is located on one straight line. This will be described in more detail with reference to Fig.
  • FIG. 8 is a view schematically showing a configuration of a plurality of welding spots provided in an electrode lead in a battery module according to an embodiment of the present invention.
  • FIG. 8 is an example of an enlarged configuration for the portion B2 in FIG.
  • a large number of the welding spots W1 may be formed on the electrode leads in the vertical direction (the Z-axis direction in the figure).
  • the welding spots located at the uppermost position are referred to as a first welding spot Wa and the second welding spot Wb and the third welding spot Wc are sequentially referred to as a downward direction.
  • these three weld spots can each be configured in the form of a tornado consisting of two spirals, i.e. two weld lines.
  • each outer end, the first welding line Wc1 of the third welding spot, and the outer end of the second welding line Wc2 may all be configured to lie on one straight line labeled c4. That is, in this case, the six outer ends provided in the three welding spots can be configured to be all located on the same straight line.
  • the welding power of the workpieces by a plurality of welding spots can be further improved.
  • the force due to vibration or impact that is, the tensile force can be generated in the left-right direction.
  • the weld strength is weakened by the fatigue formed at the outer end Prevention or reduction.
  • the welding spot W may be configured to be welded between the electrode lead and the electrode lead, and / or between the electrode lead and the bus bar, as described above.
  • the welding spot W may be configured to weld a plurality of electrode leads and a bus bar together. This will be described in more detail with reference to FIG.
  • FIG. 9 is a cross-sectional view schematically showing a welding configuration between an electrode lead and a bus bar in a battery module according to an embodiment of the present invention.
  • FIG. 9 is an example of a sectional configuration taken along line B3-B3 'in FIG. In Fig. 9, for convenience of explanation, only a part of the electrode lead and a bus bar are shown.
  • a plurality of electrode leads that is, two electrode leads 111 are overlapped with each other in the left-right direction (Y-axis direction in the figure) (Upper surface in Fig. 9).
  • the two electrode leads 111 and one bus bar 200 are laminated in the front-rear direction (X-axis direction in the drawing).
  • the two electrode leads 111 and one bus bar 200 stacked one upon the other can be welded by one or more welding spots W. 3 and 4, two mutually stacked electrode leads 111 and one bus bar 200 are welded together by a plurality, such as six to eight weld spots W. [ .
  • each welding spot may have a first welding line W1 and a second welding line W2, as shown in Fig. 9, wherein each of the two welding lines may be formed in a spiral shape .
  • each weld spot may be configured in any one of the weld spot shapes shown in FIGS. 5-8. Therefore, in one cross section of the configuration in which the two electrode leads and the bus bar are combined, as shown in Fig. 9, a welding portion by a plurality of welding lines can be formed.
  • the plurality of electrode leads 111 are made of the same material, and the bus bar 200 may be made of a material different from the electrode leads.
  • the two electrode leads 111 may be made of aluminum and one bus bar 200 may be made of copper.
  • a plurality of secondary batteries are electrically connected in parallel, such a configuration may be provided.
  • the electrode leads and the bus bars which are mutually coupled and fixed to each other, are made of different materials, it is preferable that they are welded to each other by one or more welding spots formed in a tornado shape as in the present invention.
  • the weldability between a plurality of electrode leads and the bus bar can be stably secured.
  • the material of the electrode lead and the bus bar may be made of various materials according to various factors such as the type of the battery, the battery pack, and the characteristics of the device to which the battery pack is applied.
  • the two electrode leads that is, the positive electrode lead and the negative electrode lead, may be made of different materials.
  • one electrode lead and the bus bar may be made of the same material.
  • both of the two electrode leads and the bus bar may be made of the same material.
  • FIG. 9 two electrode leads and one bus bar are shown as being welded to each other. However, this is merely an example, and three or more electrode leads and one bus bar may be welded together . Also, at this time, a welding spot of a tornado shape as described above can be applied.
  • the electrode lead has a recess formed inwardly concave, and the welding spot may be configured to be positioned at least partially in the recess. This will be described in more detail with reference to FIG.
  • FIG. 10 is a cross-sectional view schematically showing a welding configuration of an electrode lead and a bus bar according to another embodiment of the present invention.
  • Fig. 10 for convenience of explanation, only a part of the electrode lead and the bus bar are shown.
  • two electrode leads 111 may be laminated and welded on the front surface (upper surface in FIG. 10) of the bus bar 200 by approaching from both sides with respect to one bus bar 200.
  • the two electrode leads 111 may each have a concave portion formed in a recessed shape in the inner direction (+ X-axis direction in Fig. 10) as indicated by G1 in Fig.
  • the inward direction refers to a direction toward the center of the battery module or the secondary battery, and may be a direction opposite to a direction in which the electrode leads protrude from the secondary battery body.
  • each electrode lead 111 extends upward (in the -X-axis direction in the drawing) and then bent in the horizontal direction (Y-axis direction) , It may be configured such that it is bent in the horizontal direction to form a concave portion and the end portion is bent upward again.
  • all or a part of the welding spot W may be located in the concave portion G1 formed by the bending of the electrode lead. That is, as shown in FIG. 10, the welding spot W may be located at a portion formed concavely in the two electrode leads 111.
  • the bonding force between the electrode leads 111 can be further improved. That is, not only the two electrode leads 111 are fixed to each other by the welding spot W, but also the mechanical coupling strength can be further improved by the coupling between the recesses G1. That is, when the concave portion is formed in the electrode lead located relatively forward (the upper portion in Fig. 10), a convex portion may be formed on the rear side of the electrode lead. The convex portion can be inserted into the concave portion of the electrode lead located further behind. Therefore, by this insertion between the electrode leads, the bonding force between the electrode leads can be further improved.
  • the tensile force applied to the weld spot W can be reduced by the concave portion G1.
  • the concave portion G1 formed in the electrode lead can buffer the lateral force applied to the electrode lead . Therefore, such a force can be reduced and transmitted to the welding spot W formed in the concave portion G1 without being transmitted.
  • the positions of the electrode leads and the positions of the welding spots can be easily grasped and guided by the concave portion G1, the bonding between the electrode leads and the welding process can be performed more smoothly.
  • one tornado that is, one welding spot is formed by two welding lines formed in a helical form.
  • three or more welding lines constitute one tornado A welding spot can be constructed.
  • FIG. 11 is a view schematically showing a configuration of a welding spot according to another embodiment of the present invention.
  • one tornado i.e., one weld spot W
  • the three welding lines w1, w2 and w3 may have a spiral shape from the outer end to the inner end, respectively.
  • the welding lines constituting the tornado are formed in a spiral shape from the outer end to the inner end, but the present invention is not necessarily limited to these embodiments.
  • FIG. 12 is a view schematically showing the configuration of a welding spot according to another embodiment of the present invention.
  • each welding line may be formed in a shape other than a complete spiral as a whole.
  • the outer end of the first welding line W1 and the outer end of the second welding line W2 can be formed in a bent form, such as a portion denoted by e1 and e2 . Further, at this time, the bent end portions of the first welding line W1 and the second welding line W2 may be formed in a straight line shape.
  • the restraining force against crack growth can be increased. Further, through the bending configuration of such a welding line, the fatigue applied to the distal end of the welding line can be reduced.
  • FIG. 13 is a view schematically showing a configuration of a welding spot according to another embodiment of the present invention.
  • each welding spot formed in a tornado shape is configured such that the width in the direction of arrangement of the welding spots is shorter than the width in the direction orthogonal thereto .
  • the width may be the distance between welding lines located at the outermost part of the welding spot.
  • the width of the weld spot may be the maximum distance of the straight line distance between the outermost weld lines of the weld spot.
  • each welding spot W when two or more welding spots W are arranged in the vertical direction (the Z-axis direction in the figure), the vertical length of each welding spot is denoted by f1, and the horizontal direction of each welding spot Axial direction) width is f2, the tornado of each welding spot can be configured in such a manner that f2 is larger than f1. In this case, it can be said that each welding spot is formed in an approximately elliptic shape.
  • the battery module according to the present invention may further include a module case and the like in addition to the cell assembly 100 and the bus bar.
  • the module case may have an empty space formed therein, and may be configured to accommodate various components such as the cell assembly 100 and the bus bar in the empty space.
  • the battery module according to the present invention may further include various components of the battery module known at the time of filing of the present invention.
  • the battery pack according to the present invention may include at least one battery module according to the present invention.
  • the battery pack according to the present invention may include a pack case for storing the battery module, various devices for controlling charge and discharge of the battery module, such as a BMS (Battery Management System), a current sensor, . ≪ / RTI >
  • the battery module according to the present invention can be applied to an automobile such as an electric car or a hybrid car. That is, the automobile according to the present invention may include a battery module according to the present invention. Particularly, in the case of the battery module according to the present invention, the electrical connection state by the welding of the electrode lead 111 and / or the bus bar can be stably maintained even in case of impact or vibration. Therefore, in the case of a vehicle to which such a battery module is applied, the safety can be greatly improved.
  • the positive electrode leads of all the samples of the embodiment are made of aluminum and have a thickness of 0.2 mm
  • the negative electrode lead is made of copper and has a thickness of 0.2 mm
  • the bus bar is made of copper and has a thickness of 0.6 mm Respectively.
  • each welding spot was configured in the form of a tornado as shown in Fig.
  • the outer diameter (longest width) of the tornado was about 3 mm
  • the number of tornadoes was 6
  • the distance between the tornados was 3.4 mm
  • the distance between the welding lines was 0.004 mm.
  • the laser output was 1.5 kW and the speed was 100 mm / s.
  • Electrode leads and bus bars having the same material and shape as those of Examples 1 to 3, they were laminated in the same manner as in Examples 1 to 3. Then, the two electrode leads and the bus bar were welded together. At this time, the welding configurations were made as shown in FIG. 1, so that the samples of Comparative Examples 1 to 3 were prepared.
  • the total length of each welding line was set to 35 mm, and the interval between the welding lines was set to 1.2 mm.
  • the laser welding equipment of Miyachi Corporation was used for welding between the two electrode leads and the bus bar.
  • the laser output was 1.5 kW and the speed was 95 mm / s.
  • the lengths of the laser welding lines in the samples of Comparative Examples 1 to 3 were substantially similar to the total length of the laser welded portions in the samples of Examples 1 to 3.
  • the electrode leads and the bus bars in contact with the electrode leads stacked in the center were pulled in directions opposite to each other.
  • the right electrode lead 111 stacked at the center pulls in the right direction
  • the bus bar 200 at the lowermost position pulls in the left direction.
  • the measurement results are shown in Fig. 15 as Examples 1 to 3 and Comparative Examples 1 to 3.
  • the tensile strength was 46.484 kgf to 48.935 kgf, and the average tensile strength was 47.530 kgf.
  • the base material strength is 57.270 kgf, where the tensile strength measurement value corresponds to about 82.99% of the base material strength.
  • the tensile strength was 37.756 kgf to 41.972 kgf, and the average tensile strength was 40.371 kgf.
  • the base material strength is 57.270 kgf, it is about 70.49% of the base material strength.
  • Samples of Examples 4 to 6 were prepared by varying only the material and / or thickness of the electrode lead and the bus bar with respect to the overall configuration of the samples of Examples 1 to 3, particularly the welding configuration.
  • both the positive electrode lead and the negative electrode lead were made of aluminum and had a thickness of 0.4 mm.
  • the bus bar is made of copper and has a thickness of 3.0 mm.
  • each welding spot is configured in a tornado shape having only one spiral welding line as shown in FIG.
  • the diameter, the number of weld spots, the interval between weld spots, and the interval between weld lines were configured in the same manner as in Examples 4 to 6, that is, in Examples 1 to 3.
  • Example 10 Samples of Example 10 were prepared in the same form and the weld configuration as the samples of Examples 4 to 6 above.
  • Example 11 Samples of Example 11 were prepared in the same form and the weld configuration as the samples of Examples 7 to 9 above.
  • FIG. 18 is an image of the tensile strength measurement method according to Example 10 taken while the experiment is conducted
  • FIG. 19 is an image showing the tensile strength measurement method according to Example 11, to be.
  • each welding spot has a plurality of helical welding lines, that is, two helical welding lines, the welding portion is not easily peeled off , It can be seen that the welding can be done with a stronger strength. Thus, it can be seen that, in the case of a weld spot having two or more helical welding lines and formed with a tornado, the reliability of welding is further improved.
  • Samples of Examples 12 to 26 were prepared in such a manner that the overall configuration, particularly the welding configuration, of the samples of Examples 1 to 3 was substantially the same, but the materials and / or thicknesses of the electrode leads and bus bars were different.
  • the cathode lead was made of aluminum material to have a thickness of 0.4 mm, and the cathode lead was made of copper material to have a thickness of 0.2 mm.
  • the bus bar was made of copper and had a thickness of 3 mm.
  • the outer diameter of the tornado was about 3 mm
  • the number of tornadoes was 6, the distance between the tornadoes was 3.4 mm, and the distance between the welding lines was 0.004 mm.
  • the laser output was 1.5 kW and the speed was 100 mm / s.
  • the laser welding equipment used was FK-F6000-MM-CT of Miyachi Corporation as in the previous embodiments.
  • the gap between the electrode leads and the bus bar is different from each other. That is, for the 15 samples of Examples 12 to 26, the gap between the electrode leads stacked in the center directly in contact with the bus bar and the bus bars located thereunder was varied within a range of 0.04 mm to 0.6 mm In this state, the electrode lead and the bus bar were welded together. At this time, the distance between the electrode lead and the bus bar was maintained by interposing an intermediate member in a predetermined portion of the spaced space. The intervals between the leads and the bus bars in each of the examples of Examples 12 to 26 are as shown in the table of Fig.
  • the electrode leads and the bus bars having the same material and shape as those of Examples 12 to 26 were stacked in the same manner as in Examples 12 to 26. Then, the two electrode leads and the bus bar were welded together. At this time, the welding configuration was the same as that of Comparative Examples 1 to 3. That is, in the case of Comparative Examples 4 to 18, two electrode leads and a bus bar were welded through two straight line welding lines as shown in FIG. The total length of the welding line was 35 mm and the distance between the welding lines was 1.2 mm. The laser output was 1.5 kW and the speed was 95 mm / s. In this case as well, the laser welding equipment used FK-F6000-MM-CT of Miyagi Korea Co., Ltd. as in the comparative examples
  • the gap (gap) between the electrode lead and the bus bar is sequentially changed from each other. That is, also in the case of Comparative Examples 4 to 18, as shown in Fig. 20, the gap between each lead and the bus bar was made to be the same as the samples of Examples 12 to 26. In this way, linear samples were welded to each of the comparative samples having different intervals.
  • the tensile strength was measured within a range of about 175 kgf to 210 kgf for all 15 samples.
  • the tensile strength was measured within the range of about 175 kgf to 210 kgf only for Comparative Examples 4 to 9 in which the gap (gap between the electrode lead and the bus bar) was set to be as small as 0.24 mm or less.
  • the tensile strength was measured as low as less than 170 kgf.
  • the weldability can be stably secured even if a gap is formed between the electrode lead and the bus bar to some extent .
  • the electrode lead and the bus bar can not be welded properly even if only 0.32 mm between the electrode lead and the bus bar is widened.
  • the weldability can be stably maintained even in the state where the gap is 0.6 mm.
  • the bus bar can be stably maintained.
  • FIG. 23 is a view schematically showing a configuration of a plurality of welding spots provided in an electrode lead in a battery module according to another embodiment of the present invention.
  • FIG. 23 is another example of the enlarged configuration for the portion B2 in FIG.
  • the present embodiment only the differences from the previous embodiments will be mainly described, and the detailed description of the parts that can be applied to the same or similar parts of the previous embodiments will be omitted.
  • each of the welding spots may be configured in the form of a tornado having two welding lines in a spiral form .
  • two or more weld spots may be configured so that the straight lines connecting the outer ends are formed in different directions. More specifically, in the configuration of Fig. 23, the straight lines connecting the respective outer ends of the three welding spots Wd, We, Wf may be formed in different directions. 23, a straight line connecting the outer ends of the two welding lines Wd1 and Wd2 to the welding spot Wd is referred to as C5 and two straight lines connecting the two welding lines We1, A straight line connecting the outer ends of the two welding lines Wf1 and Wf2 with respect to the welding spot Wf is referred to as C7. At this time, the straight lines C5, C6, and C7 may be configured so as not to be parallel to each other.
  • the straight line C6 may be configured to be inclined at an angle of about 30 degrees with respect to the straight line C5, and the straight line C7 may be configured to be inclined at an angle of about 60 degrees with respect to the straight line C5.
  • at least two or more welding spots provided in one electrode lead are not formed in exactly the same shape as each other, but are arranged in a range of more than 0 degrees and smaller than 360, It can be said that
  • the outer end connecting straight line of each welding spot may be configured so as not to be parallel to each other for all the welding spots. That is, all of the welding spots within one electrode lead are not formed to be equal to each other but may be configured to be rotated at a predetermined angle with respect to the center point.
  • the weldability between the electrode leads and / or the electrode leads and the bus bar can be stably ensured regardless of the direction in which the tensile force is applied.
  • the welding direction of the welding line at the outer end portion is formed differently for a plurality of welding spots. Therefore, in this case, even if the stress is applied in a specific direction, the fatigue of the outer end of each welding spot can be changed, and there can be a welding spot where the welding property is strongly maintained. Therefore, regardless of the direction in which the tensile force acts on the electrode leads, the weldability can be stably secured.
  • W1 first welding line
  • W2 second welding line

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Abstract

A battery module with improved weldability between electrode leads and/or between the electrode leads and bus bars is disclosed. The battery module according to the present invention comprises: a cell assembly having a plurality of secondary batteries, which are stacked in at least one direction, respectively have electrode leads, and are electrically connected to each other through the connection between the electrode leads; and one or more bus bars formed of an electrically conductive material and making contact with the electrode leads of the secondary batteries so as to be electrically connected thereto. At least one of the electrode leads can be coupled and fixed, by a welding spot formed in the shape of a tornado, to at least one of another electrode lead making contact therewith and a bus bar making contact therewith.

Description

배터리 모듈Battery module
본 출원은 2017년 7월 14일자로 출원된 한국 특허출원 번호 제10-2017-0089717호 및 2018년 7월 12일자로 출원된 한국 특허출원 번호 제10-2018-0081313호에 대한 우선권주장출원으로서, 해당 출원의 명세서 및 도면에 개시된 모든 내용은 인용에 의해 본 출원에 원용된다.This application claims priority to Korean Patent Application No. 10-2017-0089717 filed on July 14, 2017 and Korean Patent Application No. 10-2018-0081313 filed on July 12, 2018 , The disclosure of which is incorporated herein by reference in its entirety.
본 발명은 배터리 모듈에 관한 것으로서, 보다 상세하게는 전기적 연결 구조의 용접성이 향상된 배터리 모듈과 이를 포함하는 배터리 팩 및 자동차에 관한 것이다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery module, and more particularly, to a battery module having improved weldability of an electrical connection structure, a battery pack including the battery module, and an automobile.
근래에 들어서, 노트북, 스마트폰, 스마트 워치 등과 같은 휴대용 전자 제품의 수요가 급격하게 증대되고, 에너지 저장용 축전지, 로봇, 위성 등의 개발이 본격화됨에 따라, 반복적인 충방전이 가능한 고성능 이차 전지에 대한 연구가 더욱 활발히 진행되고 있다.In recent years, demand for portable electronic products such as notebooks, smart phones, and smart watches has rapidly increased, and development of batteries, robots, and satellites for energy storage has become full-scale, The research on the study is becoming more active.
현재 상용화된 이차 전지로는 니켈 카드뮴 전지, 니켈 수소 전지, 니켈 아연 전지, 리튬 이차 전지 등이 있는데, 이 중에서 리튬 이차 전지는 니켈 계열의 이차 전지에 비해 메모리 효과가 거의 일어나지 않아 충 방전이 자유롭고, 자가 방전율이 매우 낮으며 에너지 밀도가 높은 장점으로 각광을 받고 있다. The secondary rechargeable batteries are nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries. Among them, lithium secondary batteries have almost no memory effect compared to nickel- It is very popular because of its low self-discharge rate and high energy density.
이러한 리튬 이차 전지는 주로 리튬계 산화물과 탄소재를 각각 양극 활물질과 음극 활물질로 사용한다. 리튬 이차 전지는, 이러한 양극 활물질과 음극 활물질이 각각 도포된 양극판과 음극판이 세퍼레이터를 사이에 두고 배치된 전극 조립체와, 전극 조립체를 전해액과 함께 밀봉 수납하는 외장재, 즉 전지 케이스를 구비한다.These lithium secondary batteries mainly use a lithium-based oxide and a carbonaceous material as a cathode active material and an anode active material, respectively. The lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate each coated with such a positive electrode active material and a negative electrode active material are disposed with a separator interposed therebetween, and an outer casing, that is, a battery case, for sealingly storing the electrode assembly together with the electrolyte solution.
일반적으로 리튬 이차 전지는 외장재의 형상에 따라, 전극 조립체가 금속 캔에 내장되어 있는 캔형 이차 전지와 전극 조립체가 알루미늄 라미네이트 시트의 파우치에 내장되어 있는 파우치형 이차 전지로 분류될 수 있다. Generally, a lithium secondary battery can be classified into a can type secondary battery in which an electrode assembly is embedded in a metal can, and a pouch type secondary battery in which an electrode assembly is embedded in a pouch of an aluminum laminate sheet, depending on the shape of the casing.
최근에는 휴대형 전자기기와 같은 소형 장치뿐 아니라, 자동차나 전력저장장치와 같은 중대형 장치에도 이차 전지가 널리 이용되고 있다. 특히, 탄소 에너지가 점차 고갈되고 환경에 대한 관심이 높아지면서, 미국, 유럽, 일본, 한국을 비롯하여 전 세계적으로 하이브리드 자동차와 전기 자동차에 세간의 이목이 집중되고 있다. 이러한 하이브리드 자동차나 전기 자동차에 있어서 가장 핵심적 부품은 차량 모터로 구동력을 부여하는 배터리 팩이다. 하이브리드 자동차나 전기 자동차는 배터리 팩의 충방전을 통해 차량의 구동력을 얻을 수 있기 때문에, 엔진만을 이용하는 자동차에 비해 연비가 뛰어나고 공해 물질을 배출하지 않거나 감소시킬 수 있다는 점에서 사용자들이 점차 크게 늘어나고 있는 실정이다. In recent years, secondary batteries are widely used not only in small-sized devices such as portable electronic devices, but also in medium to large-sized devices such as automobiles and electric power storage devices. Particularly, as carbon energy is getting depleted and the interest in the environment is increasing, attention is focused on hybrid cars and electric cars worldwide, including the US, Europe, Japan, and Korea. The most important components in such hybrid vehicles and electric vehicles are battery packs that give drive power to vehicle motors. Since hybrid vehicles and electric vehicles can obtain the driving force of the vehicle through charging and discharging of the battery pack, the fuel efficiency is higher than that of the vehicle using only the engine, and the users are increasingly increasing in terms of not discharging or reducing pollutants. to be.
대부분의 배터리 팩, 특히 하이브리드 자동차나 전기 자동차, ESS(Energy Storage System)와 같은 중대형 배터리 팩에는 다수의 이차 전지가 포함되며, 이러한 다수의 이차 전지들은 서로 직렬 및/또는 병렬로 연결되어, 용량 및 출력이 향상되도록 한다. 더욱이, 중대형 배터리 팩에는 적층이 용이하고 무게가 가벼우며 많은 개수를 포함시킬 수 있다는 등의 장점으로 인해 파우치형 이차 전지가 많이 이용된다.BACKGROUND OF THE INVENTION Most battery packs, particularly medium- to large-sized battery packs such as hybrid cars, electric vehicles and Energy Storage Systems (ESS), include a plurality of secondary batteries, which are connected in series and / So that the output is improved. Furthermore, pouch-type secondary batteries are widely used because they are easy to be stacked, light in weight, and can contain a large number of batteries in a middle- or large-sized battery pack.
이와 같은 파우치형 이차 전지에 있어서, 이차 전지 사이의 전기적 연결은 전극 리드를 서로 직접 접촉시키는 방식으로 구성되는 경우가 많다. 이때, 이차 전지를 병렬로 연결시키기 위해서는 동일 극성의 전극 리드를 서로 연결시키고 직렬로 연결시키기 위해서는 다른 극성의 전극 리드를 서로 연결시킨다.In such a pouch-type secondary battery, the electrical connection between the secondary batteries is often constituted by a method of directly contacting the electrode leads with each other. At this time, in order to connect the secondary batteries in parallel, the electrode leads of the same polarity are connected to each other and the electrode leads of the other polarity are connected to each other in order to connect them in series.
또한, 이차 전지의 전기적 연결 및/또는 전압 센싱 등을 위해, 버스바가 전극 리드, 특히 둘 이상의 전극 리드와 접합될 수 있다. 이때, 전극 리드와 버스바의 접합 연결은 용접 방식으로 이루어지는 경우가 많다.Further, for electrical connection and / or voltage sensing of the secondary battery, the bus bar may be bonded to the electrode lead, particularly, to two or more electrode leads. At this time, the connection between the electrode lead and the bus bar is often made by welding.
도 1은, 종래 배터리 모듈에서 전극 리드와 버스바가 서로 용접된 구성을 개략적으로 나타내는 부분 사시도이다. 그리고, 도 2는, 도 1의 A1-A1'선에 대한 단면 구성으로서, 용접된 부분을 도식화하여 나타낸 도면이다.1 is a partial perspective view schematically showing a structure in which an electrode lead and a bus bar are welded to each other in a conventional battery module. Fig. 2 is a cross-sectional view taken along the line A1-A1 'in Fig. 1, and is a diagram showing the welded part in a schematic form.
도 1 및 도 2를 참조하면, 종래 배터리 모듈에서 2개의 전극 리드(10)와 1개의 버스바(20)가 서로 용접될 때, 용접은, A2로 표시된 바와 같이, 주로 직선 형태로 이루어지는 경우가 많다. 그리고, 이때 용접 라인의 길이 방향은 전극 리드의 폭 방향으로 이루어진다.Referring to FIGS. 1 and 2, when two electrode leads 10 and one bus bar 20 are welded to each other in a conventional battery module, welding is performed mainly in a linear shape as indicated by A2 many. At this time, the longitudinal direction of the welding line is in the width direction of the electrode lead.
그런데, 이러한 종래의 전극 리드(10)와 버스바(20) 사이의 용접 구성에 의하면, 용접성이 떨어진다는 문제가 있다. 특히, 이러한 용접은 주로 레이저 용접 방식으로 이루어지는 경우가 많은데, 용접부는 레이저에 의해 매우 경화되어 있어, 충격이나 진동에 취약할 수 있다.According to the conventional welding configuration between the electrode lead 10 and the bus bar 20, there is a problem in that the weldability is deteriorated. Particularly, such welding is mainly performed by a laser welding method. Since the welded portion is very hardened by a laser, it may be vulnerable to impact or vibration.
더욱이, 이러한 종래의 용접 구성에 의하면, 용접부 내부에 기공이나 크랙이 발생 시, 외부 진동이나 충격에 의해 크랙의 성장이 매우 빠르게 일어날 수 있다. 예를 들어, 도 1의 A3 지점에서 크랙이 발생한 경우, 이러한 크랙은 진동이나 충격에 의해, 화살표 A4 방향, 즉 용접 라인의 길이 방향을 따라, 빠르게 확대될 수 있다.Moreover, according to such a conventional welding configuration, when pores or cracks are generated in the welded portion, cracks can be rapidly grown due to external vibration or impact. For example, when a crack occurs at a point A3 in Fig. 1, such a crack can be rapidly enlarged along the direction of the arrow A4, that is, along the length direction of the welding line, by vibration or impact.
특히, 외력이 인가되는 방향은 용접 라인과 직각을 이루는 방향(도 1의 좌우 방향)일 수 있는데, 이 경우 외력이 인가되는 방향으로는 용접부의 단면적이 좁아 낮은 인장력에서도 용접 대상이 서로 박리될 우려가 있다. 더욱이, 종래의 직선 용접 구성에 의하면, 용접 라인의 단부에서부터 크랙이 시작되는 경우가 많다. 그리고, 이러한 크랙은 용접 라인을 따라 계속해서 성장해나갈 우려가 있다.Particularly, the direction in which the external force is applied may be a direction perpendicular to the welding line (left and right direction in FIG. 1). In this case, the cross-sectional area of the welded portion in the direction in which the external force is applied is low, . Furthermore, according to the conventional straight-line welding configuration, cracks often start from the end of the welding line. These cracks may continue to grow along the weld line.
뿐만 아니라, 이러한 종래의 직선 형태 용접 구성에 의하면, 어느 일단의 용접 강도가 떨어질 수 있다. 예를 들어, 도 1의 구성에서, 레이저가 용접 라인의 일단에서 시작하여 타단까지 연속하여 조사되는 형태로 용접이 이루어질 수 있는데, 용접이 시작되는 부분에서는 전극 리드에 충분한 열이 전달되지 못해 용접 강도가 떨어지는 문제가 발생할 수 있다.In addition, according to such a conventional straight-line welding configuration, the welding strength at any one end can be reduced. For example, in the configuration of FIG. 1, welding may be performed in such a manner that the laser is continuously irradiated from one end of the welding line to the other end. In the portion where welding starts, sufficient heat is not transferred to the electrode lead, There may be a problem of falling.
이처럼, 종래 전극 리드 사이 및/또는 전극 리드와 버스바 사이의 용접 구성에 의하면, 용접성이 떨어지며, 특히 진동이나 충격에 취약한 문제가 있다. 더욱이, 배터리 모듈이 자동차에 적용된 경우, 크고 많은 진동이나 충격에 노출될 수 있으므로, 이러한 전극 리드 및/또는 버스바의 연결을 위한 용접성이 안정적으로 확보될 필요가 있다.As described above, according to the welding configuration between the conventional electrode leads and / or the electrode leads and the bus bar, there is a problem that the weldability is poor, and particularly, it is vulnerable to vibration and impact. Furthermore, when the battery module is applied to an automobile, it may be exposed to a large and large vibration or shock, and therefore it is necessary that the weldability for the connection of the electrode lead and / or the bus bar is stably secured.
따라서, 본 발명은 상기와 같은 문제점을 해결하기 위해 창안된 것으로서, 전극 리드 사이 및/또는 전극 리드와 버스바 사이의 용접성이 개선된 배터리 모듈 및 이를 포함하는 배터리 팩과 자동차를 제공하는 것을 목적으로 한다.SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a battery module improved in weldability between electrode leads and / or electrode leads and a bus bar, and a battery pack and a vehicle including the same, do.
본 발명의 다른 목적 및 장점들은 하기의 설명에 의해서 이해될 수 있으며, 본 발명의 실시예에 의해 보다 분명하게 알게 될 것이다. 또한, 본 발명의 목적 및 장점들은 특허 청구 범위에 나타낸 수단 및 그 조합에 의해 실현될 수 있음을 쉽게 알 수 있을 것이다.Other objects and advantages of the present invention will become apparent from the following description, and it will be understood by those skilled in the art that the present invention is not limited thereto. It will also be readily apparent that the objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
상기와 같은 목적을 달성하기 위한 본 발명에 따른 배터리 모듈은, 적어도 일 방향으로 적층되고 각각 전극 리드를 구비하며, 상기 전극 리드 간 연결을 통해 상호 전기적으로 연결된 다수의 이차 전지를 구비하는 셀 어셈블리; 및 전기 전도성 재질로 구성되어 상기 이차 전지의 전극 리드와 접촉하여 전기적으로 연결된 하나 이상의 버스바를 포함하고, 적어도 하나의 전극 리드는, 접촉된 다른 전극 리드 및 접촉된 버스바 중 적어도 하나와, 토네이도 형태로 형성된 용접 스팟에 의해 결합 고정될 수 있다.According to an aspect of the present invention, there is provided a battery module comprising: a cell assembly including a plurality of secondary cells stacked in at least one direction and each having an electrode lead, the plurality of secondary cells being electrically connected through the electrode leads; And at least one electrode lead formed of an electrically conductive material and electrically connected to the electrode lead of the secondary battery, wherein at least one of the electrode leads includes at least one of the other electrode leads and the contacted bus bars, As shown in Fig.
여기서, 상기 용접 스팟은, 나선 형태의 복수의 용접 라인을 구비하는 형태로 구성될 수 있다.Here, the welding spot may be configured to have a plurality of spiral welding lines.
또한, 상기 용접 스팟은, 상기 복수의 용접 라인이 서로 동일한 회전 방향을 가지며, 하나의 용접 라인의 적어도 일부가 다른 용접 라인 사이에 삽입된 형태로 구성될 수 있다.Further, the welding spot may be configured such that the plurality of welding lines have the same rotational direction as each other, and at least a part of one welding line is inserted between the other welding lines.
또한, 상기 용접 스팟은, 복수의 용접 라인의 각 내측 단부를 연결하는 직선 및 각 외측 단부를 연결하는 직선이 서로 평행하도록 구성될 수 있다.Further, the welding spot may be configured such that a straight line connecting each inner end of the plurality of welding lines and a straight line connecting the respective outer ends are parallel to each other.
또한, 상기 용접 스팟은, 복수의 용접 라인의 내측 단부가 서로 연결되도록 구성될 수 있다.Further, the welding spot may be configured so that the inner ends of the plurality of welding lines are connected to each other.
또한, 상기 용접 스팟은, 하나의 전극 리드에 대하여 다수 구비될 수 있다.In addition, a plurality of welding spots may be provided for one electrode lead.
또한, 하나의 전극 리드에 구비된 다수의 용접 스팟은, 외측 단부가 하나의 직선 상에 위치하도록 구성될 수 있다.Further, a plurality of welding spots provided in one electrode lead can be configured so that the outer end thereof is positioned on one straight line.
또한, 상기 용접 스팟은, 상호 적층된 다수의 전극 리드 및 1개의 버스바를 용접하도록 구성될 수 있다.Further, the welding spot may be configured to weld a plurality of mutually stacked electrode leads and one bus bar.
또한, 상기 전극 리드는, 내측 방향으로 오목하게 형성된 오목부를 구비하고, 상기 용접 스팟은, 적어도 일부가 상기 오목부에 위치하도록 구성될 수 있다.Further, the electrode lead may have a concave portion formed concavely inwardly, and the welding spot may be configured such that at least a part of the welding spot is located in the concave portion.
또한, 상기와 같은 목적을 달성하기 위한 본 발명에 따른 배터리 팩은, 본 발명에 따른 배터리 모듈을 포함한다.According to another aspect of the present invention, there is provided a battery pack including a battery module according to the present invention.
또한, 상기와 같은 목적을 달성하기 위한 본 발명에 따른 자동차는, 본 발명에 따른 배터리 모듈을 포함한다.According to another aspect of the present invention, there is provided an automobile including the battery module according to the present invention.
본 발명에 의하면, 전극 리드 사이 및/또는 전극 리드와 버스바 사이의 용접성이 좋아지고 용접 강도가 향상될 수 있다.According to the present invention, the weldability between the electrode leads and / or between the electrode leads and the bus bar is improved, and the welding strength can be improved.
특히, 본 발명의 일 측면에 의하면, 길이 방향으로 전극 리드가 서로 결합되어 용접된 구성에 있어서, 전극 리드의 길이 방향으로 힘이 작용하는 경우, 이러한 힘이 작용하는 방향으로 용접 면적이 증가될 수 있다. 따라서, 본 발명의 이러한 측면에 의하면, 전극 리드 간 및/또는 전극 리드와 버스바 간 연결 부분에 대한 인장 강도가 향상될 수 있다.Particularly, according to one aspect of the present invention, in a structure in which electrode leads are welded to each other in the longitudinal direction, when a force acts in the longitudinal direction of the electrode lead, the welding area can be increased in the direction in which such force acts have. Therefore, according to this aspect of the present invention, tensile strength can be improved between the electrode leads and / or between the electrode leads and the bus bars.
또한, 본 발명의 일 측면에 의하면, 전극 리드 사이 및/또는 전극 리드와 버스바 사이의 접합면에서 용접 면적이 증가되어, 용접 부분의 인장 강도가 향상될 수 있다.Further, according to one aspect of the present invention, the welding area increases between the electrode leads and / or between the electrode leads and the bus bar, so that the tensile strength of the welding portion can be improved.
그리고, 본 발명의 일 측면에 의하면, 용접 라인의 소정 지점에서 크랙이 발생하더라도, 크랙이 크게 성장하는 것을 효과적으로 방지할 수 있다.According to an aspect of the present invention, it is possible to effectively prevent a large crack from growing even if a crack occurs at a predetermined point of the welding line.
더욱이, 본 발명에 따른 배터리 모듈이 전기 자동차와 같이 충격이나 진동에 자주 노출되는 장치에 적용되더라도, 전기적 연결 구조의 용접 상태가 안정적으로 유지될 수 있다.Furthermore, even if the battery module according to the present invention is applied to an apparatus that is frequently exposed to impact or vibration, such as an electric vehicle, the welding state of the electrical connection structure can be stably maintained.
본 명세서에 첨부되는 다음의 도면들은 본 발명의 바람직한 실시예를 예시하는 것이며, 후술하는 발명의 상세한 설명과 함께 본 발명의 기술사상을 더욱 이해시키는 역할을 하는 것이므로, 본 발명은 그러한 도면에 기재된 사항에만 한정되어 해석되어서는 아니 된다.BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate preferred embodiments of the invention and, together with the description of the invention given below, serve to further the understanding of the technical idea of the invention, And should not be construed as limiting.
도 1은, 종래 배터리 모듈에서 전극 리드와 버스바가 서로 용접된 구성을 개략적으로 나타내는 부분 사시도이다. 1 is a partial perspective view schematically showing a structure in which an electrode lead and a bus bar are welded to each other in a conventional battery module.
도 2는, 도 1의 A1-A1'선에 대한 단면 구성으로서, 용접된 부분을 도식화하여 나타낸 도면이다.Fig. 2 is a cross-sectional view taken along the line A1-A1 'in Fig. 1, and is a diagram showing the welded part in a schematic form.
도 3은, 본 발명의 일 실시예에 따른 배터리 모듈의 구성을 개략적으로 나타내는 사시도이다. 3 is a perspective view schematically showing a configuration of a battery module according to an embodiment of the present invention.
도 4는, 본 발명의 일 실시예에 따른 배터리 모듈의 구성을 정면에서 바라본 형태의 도면이다.FIG. 4 is a front view of the configuration of a battery module according to an embodiment of the present invention.
도 5는, 본 발명에 따른 배터리 모듈의 전극 리드에 적용된 용접 스팟의 구성을 개략적으로 나타내는 도면이다.5 is a view schematically showing a configuration of a welding spot applied to an electrode lead of a battery module according to the present invention.
도 6은, 본 발명의 다른 실시예에 따른 용접 스팟의 토네이도 형태를 개략적으로 나타내는 도면이다.6 is a diagram schematically illustrating a tornado shape of a welding spot according to another embodiment of the present invention.
도 7은, 본 발명의 또 다른 실시예에 따른 용접 스팟의 토네이도 형태를 개략적으로 나타내는 도면이다.7 is a schematic representation of a tornado shape of a weld spot in accordance with another embodiment of the present invention.
도 8은, 본 발명의 일 실시예에 따른 배터리 모듈에서, 전극 리드에 구비된 다수의 용접 스팟의 구성을 개략적으로 나타내는 도면이다.8 is a view schematically showing a configuration of a plurality of welding spots provided in an electrode lead in a battery module according to an embodiment of the present invention.
도 9는, 본 발명의 일 실시예에 따른 배터리 모듈에서 전극 리드와 버스바 사이의 용접 구성을 개략적으로 나타내는 단면도이다.9 is a cross-sectional view schematically showing a welding configuration between an electrode lead and a bus bar in a battery module according to an embodiment of the present invention.
도 10은, 본 발명의 다른 실시예에 따른 전극 리드와 버스바의 용접 구성을 개략적으로 나타내는 단면도이다.10 is a cross-sectional view schematically showing a welding configuration of an electrode lead and a bus bar according to another embodiment of the present invention.
도 11은, 본 발명의 다른 실시예에 따른 용접 스팟의 구성을 개략적으로 나타내는 도면이다.11 is a view schematically showing a configuration of a welding spot according to another embodiment of the present invention.
도 12는, 본 발명의 또 다른 실시예에 따른 용접 스팟의 구성을 개략적으로 나타내는 도면이다.12 is a view schematically showing the configuration of a welding spot according to another embodiment of the present invention.
도 13은, 본 발명의 다른 실시예에 따른 용접 스팟의 구성을 개략적으로 나타내는 도면이다.13 is a view schematically showing a configuration of a welding spot according to another embodiment of the present invention.
도 14는, 본 발명의 일 실시예에 따른 전극 리드와 버스바의 용접 구성을 개략적으로 나타내는 도면이다.14 is a view schematically showing a welding configuration of an electrode lead and a bus bar according to an embodiment of the present invention.
도 15는, 본 발명의 여러 실시예 및 비교예 샘플에 대한 인장 강도 측정 결과를 나타내는 도면이다.Fig. 15 is a view showing tensile strength measurement results for various examples and comparative samples of the present invention. Fig.
도 16은, 본 발명의 또 다른 실시예에 따른 전극 리드의 용접 구성을 개략적으로 나타내는 도면이다.16 is a view schematically showing a welding configuration of an electrode lead according to another embodiment of the present invention.
도 17은, 본 발명의 여러 다른 실시예에 대한 인장 강도 측정 결과를 나타내는 도면이다.17 is a view showing tensile strength measurement results of various other embodiments of the present invention.
도 18은, 본 발명의 일 실시예에 대한 인장 강도 측정에 따른 박리 여부를 촬영한 이미지이다.FIG. 18 is an image of the peeling according to the tensile strength measurement according to one embodiment of the present invention. FIG.
도 19는, 본 발명의 다른 실시예에 대한 인장 강도 측정에 따른 박리 여부를 촬영한 이미지이다.Fig. 19 is an image of the peeling test according to the tensile strength measurement according to another embodiment of the present invention.
도 20은, 본 발명의 여러 실시예 및 비교예 샘플에 대하여 적용된 전극 리드와 버스바 사이의 간격을 나타내는 도면이다.20 is a view showing the interval between the electrode lead and the bus bar applied to various embodiments of the present invention and a comparative sample.
도 21은, 도 20의 여러 실시예 및 비교예 샘플에 대하여 육안으로 관측된 결함 측정 결과를 나타내는 도면이다.Fig. 21 is a diagram showing the result of defect measurement observed visually with respect to various examples and comparative samples of Fig. 20; Fig.
도 22는, 도 20의 여러 실시예 및 비교예 샘플에 대한 인장 강도 측정 결과를 나타내는 도면이다.Fig. 22 is a view showing tensile strength measurement results for various examples and comparative samples of Fig. 20; Fig.
도 23은, 본 발명의 또 다른 실시예에 따른 배터리 모듈에서, 전극 리드에 구비된 다수의 용접 스팟의 구성을 개략적으로 나타내는 도면이다.23 is a view schematically showing a configuration of a plurality of welding spots provided in an electrode lead in a battery module according to another embodiment of the present invention.
이하, 첨부된 도면을 참조하여 본 발명의 바람직한 실시예를 상세히 설명하기로 한다. 이에 앞서, 본 명세서 및 청구범위에 사용된 용어나 단어는 통상적이거나 사전적인 의미로 한정해서 해석되어서는 안 되며, 발명자는 그 자신의 발명을 가장 최선의 방법으로 설명하기 위해 용어의 개념을 적절하게 정의할 수 있다는 원칙에 입각하여 본 발명의 기술적 사상에 부합하는 의미와 개념으로 해석되어야만 한다.Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings, and the inventor should appropriately interpret the concept of the term appropriately It should be interpreted in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined.
따라서, 본 명세서에 기재된 실시예와 도면에 도시된 구성은 본 발명의 가장 바람직한 일 실시예에 불과할 뿐이고 본 발명의 기술적 사상에 모두 대변하는 것은 아니므로, 본 출원시점에 있어서 이들을 대체할 수 있는 다양한 균등물과 변형예들이 있을 수 있음을 이해하여야 한다.Therefore, the embodiments described in the present specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.
도 3은, 본 발명의 일 실시예에 따른 배터리 모듈의 구성을 개략적으로 나타내는 사시도이다. 또한, 도 4는, 본 발명의 일 실시예에 따른 배터리 모듈의 구성을 정면에서 바라본 형태의 도면이다.3 is a perspective view schematically showing a configuration of a battery module according to an embodiment of the present invention. 4 is a front view of the configuration of a battery module according to an embodiment of the present invention.
도 3 및 도 4를 참조하면, 본 발명에 따른 배터리 모듈은, 셀 어셈블리(100) 및 버스바(200)를 포함할 수 있다.3 and 4, the battery module according to the present invention may include a cell assembly 100 and a bus bar 200.
상기 셀 어셈블리(100)는, 다수의 이차 전지(110)를 구비할 수 있다. 특히, 셀 어셈블리(100)에는 이차 전지(110)로서 파우치형 이차 전지가 복수 개 포함될 수 있다. 이러한 파우치형 이차 전지(110)는, 전극 조립체, 전해질 및 파우치 외장재를 구비할 수 있다.The cell assembly 100 may include a plurality of secondary batteries 110. In particular, the cell assembly 100 may include a plurality of pouch-type secondary batteries as the secondary batteries 110. The pouch-type secondary battery 110 may include an electrode assembly, an electrolyte, and a pouch exterior member.
여기서, 전극 조립체는, 하나 이상의 양극판 및 하나 이상의 음극판이 세퍼레이터를 사이에 두고 배치된 형태로 구성될 수 있다. 보다 구체적으로, 전극 조립체는, 하나의 양극판과 하나의 음극판이 세퍼레이터와 함께 권취된 권취형, 및 다수의 양극판과 다수의 음극판이 세퍼레이터를 사이에 두고 교대로 적층된 스택형 등으로 구분될 수 있다.Here, the electrode assembly may be configured such that at least one positive electrode plate and at least one negative electrode plate are disposed with the separator interposed therebetween. More specifically, the electrode assembly can be divided into a winding type in which one positive electrode plate and one negative electrode plate are wound together with a separator, and a stacked type in which a plurality of positive electrode plates and a plurality of negative electrode plates are alternately stacked with a separator interposed therebetween .
또한, 파우치 외장재는, 외부 절연층, 금속층 및 내부 접착층을 구비하는 형태로 구성될 수 있다. 보다 구체적으로, 이러한 파우치 외장재는, 전극 조립체와 전해액 등 내부 구성요소를 보호하고, 전극 조립체와 전해액에 의한 전기 화학적 성질에 대한 보완 및 방열성 등을 제고하기 위하여 금속 박막(금속층), 이를테면 알루미늄 박막이 포함된 형태로 구성될 수 있다. 그리고, 이러한 알루미늄 박막은, 전극 조립체 및 전해액과 같은 이차 전지(110) 내부의 구성요소나 이차 전지(110) 외부의 다른 구성 요소와의 전기적 절연성을 확보하기 위해, 절연물질로 형성된 절연층(외부 절연층, 내부 접착층) 사이에 개재될 수 있다.Further, the pouch exterior member may be configured in the form of an external insulating layer, a metal layer, and an internal adhesive layer. More specifically, such a pouch case is provided with a metal thin film (metal layer), such as an aluminum thin film, for protecting internal components such as an electrode assembly and an electrolytic solution, complementing the electrochemical properties of the electrode assembly and electrolyte, And can be configured to be included. In order to ensure electrical insulation between the internal components of the secondary battery 110 such as the electrode assembly and the electrolytic solution and other components outside the secondary battery 110, An insulating layer, an inner adhesive layer).
특히, 파우치 외장재는, 2개의 파우치로 구성될 수 있으며, 그 중 적어도 하나에는 오목한 형태의 내부 공간이 형성될 수 있다. 그리고, 이러한 파우치의 내부 공간에는 전극 조립체가 수납될 수 있다. 이때, 2개의 파우치의 외주면에는 실링부가 구비되어 이러한 실링부가 서로 융착됨으로써, 전극 조립체가 수용된 내부 공간이 밀폐되도록 할 수 있다.Particularly, the pouch exterior member can be composed of two pouches, and at least one of them can be formed with a concave internal space. The electrode assembly can be housed in the inner space of the pouch. At this time, a sealing portion is provided on the outer circumferential surface of the two pouches, and these sealing portions are fusion-bonded to each other, so that the inner space accommodating the electrode assembly can be sealed.
본 발명의 일 측면에 따른 배터리 모듈에는, 본원발명의 출원 시점에 공지된 다양한 형태의 파우치형 이차 전지가 채용될 수 있다. 따라서, 상기 셀 어셈블리(100)에 구비되는 이차 전지(110)의 내부 구성에 대한 보다 상세한 설명은 생략한다.The battery module according to one aspect of the present invention may employ various types of pouch-type secondary batteries known at the time of filing of the present invention. Therefore, detailed description of the internal structure of the secondary battery 110 provided in the cell assembly 100 will be omitted.
다수의 파우치형 이차 전지(110)는, 적어도 일 방향, 이를테면 도면에 도시된 바와 같이 좌우 방향(도면의 Y축 방향)으로 적층될 수 있다. 이때, 각각의 파우치형 이차 전지(110)는, 지면(도면의 X-Y 평면)에 대하여 상하 방향(도면의 Z축 방향)으로 세워진 형태, 즉 넓은 면이 좌우 측을 향하고 실링부가 상하 및 전후 측에 위치하도록 구성될 수 있다. 또한, 이 경우, 각각의 이차 전지(110)는, 넓은 면이 서로 대면되도록 배치될 수 있다. The plurality of pouch-shaped secondary batteries 110 may be stacked in at least one direction, for example, the lateral direction (Y-axis direction in the figure) as shown in the figure. At this time, each of the pouch-shaped secondary batteries 110 has a shape erected in a vertical direction (Z-axis direction in the drawing) with respect to the sheet surface (XY plane in the figure), that is, a shape in which the large surface faces right and left, . ≪ / RTI > In this case, each of the secondary batteries 110 can be arranged such that the large surfaces face each other.
한편, 본 명세서에서는, 특별한 설명이 없는 한, 도 3의 구성에서 전극 리드(111)가 보이는 측을 배터리 모듈의 전면이라 하고, 이러한 전면을 바라보는 관점에서, 상, 하, 좌, 우, 전, 후 등의 방향을 정의하도록 한다.3, the side where the electrode lead 111 is seen is referred to as the front side of the battery module. From the viewpoint of the front side, the upper, lower, left, right, front , And the back direction.
상기 셀 어셈블리(100)에 구비된 각각의 이차 전지(110)는, 전극 리드(111)를 구비할 수 있다. 이러한 전극 리드(111)에는 양극 리드 및 음극 리드가 포함되며, 이차 전지(110)의 전극 단자로서 기능할 수 있다. 더욱이, 파우치형 이차 전지(110)에서, 전극 리드(111)는 판상으로 구성되어 파우치 외장재 외부로 돌출될 수 있다. 본 발명에 따른 배터리 모듈에서, 각 이차 전지(110)의 전극 리드는, 셀 어셈블리(100)의 전단부 및 후단부 중 적어도 일측에서, 셀 어셈블리(100)의 전방(도면의 -X축 방향) 또는 후방(도면의 +X축 방향)으로 돌출되도록 구성될 수 있다. 상기 전극 리드(111)는, 전지의 단자로서 기능하기 위해, 알루미늄 또는 구리와 같은 금속 재질로 이루어질 수 있다. 이러한 전극 리드(111)는, 다양한 두께로 형성될 수 있다. 예를 들어, 전극 리드(111)는, 0.1mm 내지 1mm의 두께를 가질 수 있다. 보다 구체적으로, 전극 리드(111)는, 0.2mm 내지 0.6mm의 두께를 가질 수 있다. 또한, 전극 리드(111)는, 다양한 폭을 갖도록 구성될 수 있다. 예를 들어, 전극 리드(111)는, 20mm 내지 60mm의 폭을 갖도록 구성될 수 있다. 다만, 이러한 전극 리드(111)의 두께나 폭은 전지 또는 배터리 팩의 사양이나 종류 등에 따라 다양하게 구성될 수 있음은 물론이다.Each of the secondary batteries 110 included in the cell assembly 100 may include an electrode lead 111. The electrode lead 111 includes a positive electrode lead and a negative electrode lead, and can function as an electrode terminal of the secondary battery 110. Further, in the pouch type secondary battery 110, the electrode leads 111 are formed in a plate-like shape and can protrude to the outside of the pouch outer casing. In the battery module according to the present invention, the electrode leads of each secondary battery 110 are disposed in front of the cell assembly 100 (in the -X-axis direction in the drawing) from at least one of the front end portion and the rear end portion of the cell assembly 100, Or in the rear (in the + X-axis direction in the drawing). The electrode lead 111 may be made of a metal such as aluminum or copper to function as a terminal of a battery. The electrode leads 111 may be formed in various thicknesses. For example, the electrode lead 111 may have a thickness of 0.1 mm to 1 mm. More specifically, the electrode lead 111 may have a thickness of 0.2 mm to 0.6 mm. In addition, the electrode leads 111 can be configured to have various widths. For example, the electrode lead 111 may be configured to have a width of 20 mm to 60 mm. However, it is needless to say that the thickness and the width of the electrode lead 111 may be variously configured according to the specification or the type of the battery or the battery pack.
셀 어셈블리(100) 내에서 상기 이차 전지(110)는, 전극 리드(111)가 서로 연결되어 상호 전기적으로 연결될 수 있다.In the cell assembly 100, the electrode leads 111 of the secondary battery 110 may be connected to each other to be electrically connected to each other.
예를 들어, 복수의 이차 전지는, 전극 리드가 서로 직접 접촉함으로써 상호 직렬 또는 병렬로 연결될 수 있다. 다른 예로, 복수의 이차 전지는, 버스바(200)를 통해 전극 리드가 서로 간접적으로 연결됨으로써 상호 직렬 또는 병렬로 연결될 수 있다.For example, a plurality of secondary batteries can be connected to each other in series or in parallel by direct contact of the electrode leads. As another example, the plurality of secondary cells may be connected to each other in series or in parallel by indirectly connecting the electrode leads through the bus bar 200.
상기 버스바(200)는, 이차 전지의 전극 리드와 접촉되어 이차 전지의 전극 리드와 전기적으로 연결될 수 있다. 특히, 상기 버스바(200)는, 둘 이상의 전극 리드와 함께 연결됨으로써, 전극 리드 사이를 서로 전기적으로 연결할 수 있다. 또한, 상기 버스바(200)는, 적어도 하나의 전극 리드와 직접 접촉하여 연결됨으로써, 접촉된 전극 리드 측에서의 전기적 특성을 측정할 수 있다. 예를 들어, 상기 버스바(200)는 하나 이상의 이차 전지에 대하여 양단 전압을 센싱할 수 있다.The bus bar 200 may be electrically connected to an electrode lead of a secondary battery in contact with an electrode lead of the secondary battery. In particular, the bus bar 200 is electrically connected to two or more electrode leads, thereby electrically connecting the electrode leads to each other. In addition, the bus bar 200 is directly connected to at least one of the electrode leads to measure electrical characteristics at the electrode lead side. For example, the bus bar 200 may sense voltage across one or more secondary batteries.
이처럼, 상기 버스바(200)는, 이차 전지의 전극 리드(111)와 전기적으로 연결되기 위해, 전기 전도성 재질로 구성될 수 있다. 예를 들어, 상기 버스바(200)는, 구리나 알루미늄과 같은 금속 재질로 구성될 수 있다.As such, the bus bar 200 may be formed of an electrically conductive material to be electrically connected to the electrode lead 111 of the secondary battery. For example, the bus bar 200 may be made of a metal such as copper or aluminum.
또한, 상기 버스바(200)는, 전극 리드(111)와 유사하게 플레이트 형태(판상) 또는 막대 형태로 구성될 수 있다. 이때, 상기 버스바(200)는, 전극 리드(111)보다 두꺼운 두께를 갖도록 형성될 수 있다. 예를 들어, 상기 버스바(200)는, 0.3mm 내지 4mm의 두께를 갖도록 구성될 수 있다. 보다 구체적인 예로서, 이러한 버스바(200)의 두께를 전극 리드(111)와 비교하여 살펴보면, 전극 리드(111)의 두께가 0.2mm 내지 0.4mm일 때, 버스바(200)의 두께는 0.6mm 내지 3mm의 두께를 가질 수 있다. 다만, 이러한 버스바의 두께는 전지나 배터리 팩의 사양 내지 종류 등에 따라 다양하게 구성될 수 있으며, 본 발명이 이러한 버스바의 특정 두께로 한정되는 것은 아니다.In addition, the bus bar 200 may be formed in the form of a plate (plate) or rod similar to the electrode lead 111. At this time, the bus bar 200 may be formed to have a thicker thickness than the electrode lead 111. For example, the bus bar 200 may be configured to have a thickness of 0.3 mm to 4 mm. A thickness of the bus bar 200 is 0.6 mm or less when the thickness of the electrode lead 111 is 0.2 mm to 0.4 mm. Lt; RTI ID = 0.0 > mm. ≪ / RTI > However, the thickness of such a bus bar may be variously configured according to the specification or kind of the battery or the battery pack, and the present invention is not limited to the specific thickness of the bus bar.
상기 설명한 바와 같이, 셀 어셈블리(100)의 각 이차 전지(110)에 구비된 전극 리드(111)는, 버스바(200)와 결합 고정될 수 있다. 또한, 셀 어셈블리(100)에 구비된 이차 전지의 전극 리드(111)는, 다른 전극 리드(111), 즉 셀 어셈블리(100)에 구비된 다른 이차 전지의 전극 리드(111)와 결합 고정될 수 있다. 이 경우, 전극 리드(111)와 버스바(200) 사이 및/또는 전극 리드(111)와 전극 리드(111) 사이는, 용접에 의해 서로 결합 고정될 수 있다. 그리고 이때의 용접은, 레이저가 조사되어 피용접물이 용접되는 레이저 용접 방식으로 수행될 수 있다. 즉, 전극 리드(111)와 전극 리드(111) 사이 및/또는 전극 리드(111)와 버스바(200) 사이는, 레이저 용접된 형태로 구성될 수 있다.As described above, the electrode leads 111 provided in each secondary battery 110 of the cell assembly 100 can be coupled and fixed to the bus bar 200. The electrode lead 111 of the secondary battery included in the cell assembly 100 can be coupled and fixed to another electrode lead 111, that is, the electrode lead 111 of another secondary battery provided in the cell assembly 100 have. In this case, between the electrode lead 111 and the bus bar 200 and / or between the electrode lead 111 and the electrode lead 111 can be fixed to each other by welding. The welding at this time can be performed by a laser welding method in which the laser is irradiated and the workpiece is welded. That is, the space between the electrode leads 111 and the electrode leads 111 and / or between the electrode leads 111 and the bus bars 200 may be laser-welded.
셀 어셈블리(100)에 구비된 여러 이차 전지의 전극 리드(111)는, 다른 전극 리드(111)와 접촉되거나 버스바(200)와 접촉될 수 있다. 이때, 셀 어셈블리(100)에 구비된 복수의 전극 리드 중 적어도 하나의 전극 리드(111)는, 접촉된 다른 전극 리드(111) 및 접촉된 버스바(200) 중 적어도 하나와 토네이도 형태로 형성된 용접 스팟(W)에 의해 서로 결합 고정될 수 있다. The electrode leads 111 of the plurality of secondary batteries included in the cell assembly 100 may be in contact with the other electrode leads 111 or in contact with the bus bar 200. [ At least one electrode lead 111 of the plurality of electrode leads provided in the cell assembly 100 is welded to at least one of the other electrode leads 111 and the contacted bus bars 200, They can be fixed to each other by the spots W.
예를 들어, 둘 이상의 전극 리드(111)가 서로 대면 접촉된 형태로 적층된 경우, 서로 접촉된 전극 리드(111)는, 용접 스팟(W)에 의해 서로 결합 고정될 수 있다. 또한, 하나 이상의 전극 리드(111)가 버스바(200)와 대면 접촉된 형태로 적층된 경우, 전극 리드(111)와 버스바(200)는, 용접 스팟(W)에 의해 서로 결합 고정될 수 있다. 특히, 이때의 용접 스팟(W)은 토네이도 형태로 형성될 수 있다. 이러한 토네이도 형태의 용접 스팟(W) 구성은, 도 5를 참조하여 보다 구체적으로 설명하도록 한다.For example, when two or more electrode leads 111 are laminated in face-to-face contact with each other, the electrode leads 111 which are in contact with each other can be fixedly coupled to each other by the welding spot W. When the at least one electrode lead 111 is stacked in a face-to-face contact with the bus bar 200, the electrode lead 111 and the bus bar 200 can be coupled and fixed to each other by the welding spot W have. In particular, the welding spot W at this time may be formed in a tornado shape. Such a tornado-shaped welding spot W configuration will be described in more detail with reference to Fig.
도 5는, 본 발명에 따른 배터리 모듈의 전극 리드에 적용된 용접 스팟의 구성을 개략적으로 나타내는 도면이다. 예를 들어, 도 5는, 도 4의 B1 부분을 확대하여 나타낸 도면이라 할 수 있다.5 is a view schematically showing a configuration of a welding spot applied to an electrode lead of a battery module according to the present invention. For example, FIG. 5 is an enlarged view of the portion B1 in FIG.
도 5를 참조하면, 전극 리드에 적용된 용접 스팟(W)은, 용접 라인이 토네이도 형태로 구성될 수 있다. 여기서, 용접 라인은, 소정 출력 이상의 에너지를 갖는 레이저가 조사된 경로로서, 피용접물은 이러한 용접 라인을 중심으로 상호 용접될 수 있다. 특히, 본 발명에 있어서, 용접 라인은 일직선이 아닌 곡선 형태로 형성될 수 있으며, 더욱이, 이러한 곡선은 회오리 형태로 형성될 수 있다. 즉, 용접 라인은, 적어도 일부분이, 시계 방향 또는 반시계 방향으로 회전하면서, 용접 스팟(W)의 외측부에서 중앙부를 향해 나아가는 형태로 구성될 수 있다. 즉, 상기 용접 라인은, 직경이 점점 작아지는 원을 그리는 형태로 구성된다고 할 수도 있다. 여기서, 용접 라인은, 외측에서 내측(중심부) 방향, 또는 내측에서 외측 방향으로 레이저 조사 경로가 이동하는 형태로 형성될 수 있다. Referring to FIG. 5, the welding spot W applied to the electrode lead may be configured in the form of a tornado. Here, the welding line is a path irradiated with a laser having an energy of a predetermined power or more, and the workpiece can be welded to each other around the welding line. In particular, in the present invention, the welding line may be formed in a curved shape rather than a straight line, and moreover, the curved shape may be formed in a whirl-like shape. That is, the welding line may be configured such that at least a part of the welding line rotates in a clockwise or counterclockwise direction and moves from the outer side to the central side of the welding spot W. That is, the welding line may be configured to draw a circle whose diameter gradually decreases. Here, the welding line may be formed in such a manner that the laser irradiation path moves from the outside to the inside (center) direction or from the inside to the outside.
이처럼, 전극 리드와 전극 리드 사이, 및/또는 전극 리드와 버스바 사이를 용접시키는 용접 스팟(W)은, 토네이도 형태로 구성될 수 있다. 그리고, 이러한 용접 구성에 의하면, 피용접물, 즉 전극 리드와 전극 리드 사이, 및/또는 전극 리드와 버스바 사이의 용접 강도가 개선될 수 있다. 특히, 이러한 토네이도 형태의 용접 스팟(W) 구성에 의하면, 외력이 어느 방향으로 인가되더라도, 용접 부분이 균일하고 넓게 형성될 수 있다. 따라서, 여러 방향에서의 진동이나 충격에도 용접 부분이 안정적으로 유지될 수 있다.As such, the welding spot W to be welded between the electrode lead and the electrode lead, and / or between the electrode lead and the bus bar can be configured in the form of a tornado. According to this welding configuration, welding strength between the electrode to be welded, that is, between the electrode lead and the electrode lead, and / or between the electrode lead and the bus bar can be improved. Particularly, according to such a tornado-shaped welding spot W configuration, even if an external force is applied in any direction, the welding portion can be formed uniformly and widely. Therefore, the welding portion can be stably maintained even in vibration or shock in various directions.
바람직하게는, 본 발명에 따른 배터리 모듈에 있어서, 전극 리드(111) 및/또는 버스바(200)에 적용된 용접 스팟(W)은, 나선 형태로 형성된 용접 라인을 복수 구비하는 형태로 구성될 수 있다. Preferably, in the battery module according to the present invention, the welding spot W applied to the electrode lead 111 and / or the bus bar 200 may be configured to have a plurality of welding lines formed in a spiral shape. have.
예를 들어, 도 5에 도시된 바를 참조하면, 하나의 용접 스팟(W)은, 2개의 용접 라인, 즉 W1으로 표시된 제1 용접 라인 및 W2로 표시된 제2 용접 라인을 구비하는 형태로 구성될 수 있다. 이때, 제1 용접 라인(W1)과 제2 용접 라인(W2)은, 서로 다른 외측 단부를 가질 수 있다. 즉 도 5에 도시된 바와 같이, o1으로 표시된 제1 용접 라인(W1)의 외측 단부(o1)와, o2로 표시된 제2 용접 라인(W2)의 외측 단부는, 각각 별도로 형성되어 서로 다른 위치에 위치할 수 있다. For example, referring to FIG. 5, one weld spot W may be configured with two weld lines, a first weld line denoted W1 and a second weld line denoted W2 . At this time, the first welding line W1 and the second welding line W2 may have different outer ends. 5, the outer end o1 of the first welding line W1 indicated by o1 and the outer end of the second welding line W2 indicated by o2 are formed separately and at different positions Can be located.
이 경우, 서로 다른 복수의 나선, 이를테면 2개의 나선이 하나의 토네이도, 즉 하나의 용접 스팟을 형성하도록 구성되어 있다고 할 수 있다.In this case, it can be said that a plurality of different spirals, such as two spirals, are configured to form one tornado, that is, one welding spot.
이처럼, 2개의 용접 라인, 즉 2개의 나선이 하나의 토네이도를 형성하는 형태로 구성될 때, 각 나선의 내측 단부는 서로 다른 위치에 위치할 수 있다. 예를 들어, 도 5에 도시된 바와 같이, 용접 스팟(W)의 중심부에는 제1 용접 라인(W1)의 내측 단부(i1)와 제2 용접 라인(W2)의 내측 단부(i2)가 위치할 수 있으며, 이때 2개의 내측 단부(i1, i2)는 서로 분리된 형태로 구성될 수 있다. 이 경우, 제1 용접 라인(W1)과 제2 용접 라인(W2)은, 서로 연결된 부분 없이 분리된 형태로 구성되어 있다고 할 수 있다.As such, when two welding lines, that is, two spirals, are formed in the form of forming one tornado, the inner ends of the respective spirals can be located at different positions. 5, an inner end i1 of the first welding line W1 and an inner end i2 of the second welding line W2 are located at the center of the welding spot W Wherein the two inner ends i1 and i2 may be configured as separate from each other. In this case, it can be said that the first welding line W1 and the second welding line W2 are separated from each other without being connected to each other.
여기서, 상기 용접 스팟(W)은, 이를 구성하는 복수의 용접 라인이 서로 동일한 회전 방향을 갖도록 구성될 수 있다. 예를 들어, 도 5의 구성에서, 2개의 용접 라인, 즉 제1 용접 라인(W1)과 제2 용접 라인(W2)은 모두, 외측에서 내측 방향이 시계 방향이 되도록 회전하는 형태로 구성될 수 있다.Here, the welding spot W may be configured such that a plurality of welding lines constituting the welding spot W have the same rotational direction. For example, in the configuration of FIG. 5, the two welding lines, that is, the first welding line W1 and the second welding line W2 may both be configured to rotate so that the inside direction is clockwise have.
그리고, 이때, 하나의 용접 라인의 적어도 일부는, 다른 용접 라인 사이에 삽입된 형태로 구성될 수 있다. 예를 들어, 도 5의 구성에서, 제1 용접 라인(W1)은, 제2 용접 라인(W2) 사이에 일부분이 삽입된 형태로 구성될 수 있다.And, at this time, at least a part of one welding line can be configured in a form inserted between different welding lines. For example, in the configuration of Fig. 5, the first welding line W1 may be configured such that a portion thereof is inserted between the second welding lines W2.
이처럼, 나선 형태의 복수의 용접 라인이 하나의 용접 스팟(W), 즉 하나의 토네이도를 형성하는 형태로 이루어진 용접 구성에 의하면, 나선 형태로 이루어진 하나의 용접 라인이 하나의 용접 스팟을 형성하는 형태로 이루어진 용접 구성에 비해 용접 성능이 더욱 향상될 수 있다.As described above, according to the welding configuration in which the plurality of spiral-shaped welding lines form one welding spot W, that is, one tornado, one welding line in the form of a spiral forms a welding spot The welding performance can be further improved as compared with the welding configuration comprising
예를 들어, 도 5의 구성에서 제2 용접 라인(W2) 없이 제1 용접 라인(W1) 만으로 용접 스팟이 구성된 경우, 용접 방향에 따라, 용접 스팟의 외측부 또는 내측부의 용접 강도가 다소 떨어질 수 있다. 이를테면, 제1 용접 라인(W1)의 외측 단부(o1)에서 내측 단부(i1) 방향으로 레이저 조사 경로가 형성된다면, 제1 용접 라인(W1)에서 레이저가 처음 조사되는 외측 단부(o1) 부근에서는 레이저에 의한 열이 전극 리드나 버스바 측으로 충분히 전달되지 못할 수 있다. 따라서, 이러한 외측 단부(o1) 부근에서는 용접 깊이가 충분히 형성되지 못해 내측 단부(i1)에 비해 용접 강도가 떨어질 수 있다. For example, in the configuration of Fig. 5, if the welding spot is composed of only the first welding line W1 without the second welding line W2, depending on the welding direction, the welding strength of the outer or inner side of the welding spot may be somewhat lower . For example, if a laser irradiation path is formed from the outer end o1 to the inner end i1 of the first welding line W1, in the vicinity of the outer end o1 at which the laser is first irradiated in the first welding line W1 The heat generated by the laser may not be sufficiently transmitted to the electrode lead or the bus bar side. Therefore, in the vicinity of the outside end o1, the welding depth can not be sufficiently formed and the welding strength may be lower than the inside end i1.
하지만, 도 5의 구성에 도시된 바와 같이, 복수의 용접 라인, 즉 제1 용접 라인(W1)과 함께 제2 용접 라인(W2)이 하나의 용접 스팟을 구성하는 경우, 이러한 용접 스팟의 외측부 또는 내측부에서 용접 강도가 떨어지는 것을 방지하거나 감소하여, 용접성을 보다 향상시킬 수 있다.However, as shown in the configuration of Fig. 5, when a plurality of welding lines, that is, the second welding line W2 together with the first welding line W1 constitute one welding spot, It is possible to prevent or reduce the welding strength at the inner side portion and to further improve the weldability.
즉, 도 5의 구성에서, 제1 용접 라인(W1)의 형성을 위해, 먼저 제1 용접 라인(W1)의 외측 단부(o1)에서 내측 단부(i1)방향으로 레이저가 조사되는 경우, 제1 용접 라인(W1)의 외측 단부(o1) 부근의 용접 강도가 다소 저하될 수 있다. 하지만, 제2 용접 라인(W2)의 형성을 위해, 제2 용접 라인(W2)의 외측 단부(o2)에 레이저가 조사될 때에는, 이미 제1 용접 라인(W1)의 형성 단계에서 전극 리드에 충분한 열이 가해진 상태이므로, 레이저 용접이 충분한 깊이로 형성될 수 있다. 다시 말해, 제2 용접 라인(W2) 형성 시, 제1 용접 라인(W1)에 의해 전극 리드가 이미 예열된 상태이므로, 제2 용접 라인(W2)에 의한 용접이 잘 이루어질 수 있다. 따라서, 용접 스팟(W) 전체적으로는, 내측 단부는 물론이고, 외측 단부에서도 용접 강도가 충분히 확보될 수 있다.That is, in the configuration of Fig. 5, when the laser is first irradiated in the direction from the outer end o1 to the inner end il of the first welding line W1 for forming the first welding line W1, The welding strength near the outer end o1 of the welding line W1 may be somewhat lowered. However, when the laser is irradiated on the outer end o2 of the second welding line W2 for the formation of the second welding line W2, it is sufficient that the electrode lead is sufficient for forming the first welding line W1 Since the heat is applied, laser welding can be formed to a sufficient depth. In other words, at the time of forming the second welding line W2, since the electrode lead is already preheated by the first welding line W1, the welding by the second welding line W2 can be performed well. Therefore, weld strength can be sufficiently secured not only at the inner end but also at the outer end as a whole of the weld spot W. [
한편, 토네이도 형태로 구성된 용접 스팟(W)에 있어서, 각 용접 라인의 간격, 용접 스팟의 직경, 나선의 회전 수, 내측 단부 간 거리 등은, 다양한 상황, 이를테면 전극 리드나 버스바의 크기, 두께 또는 재질, 용접 스팟의 개수나 형태 등에 따라 다양하게 설정될 수 있다. On the other hand, in a welding spot W configured in the form of a tornado, the interval of each welding line, the diameter of the welding spot, the number of turns of the spiral, the distance between the inner ends, Or the material, the number and shape of the weld spots, and the like.
예를 들어, 토네이도를 구성하는 용접 라인의 간격은, 0.002 mm 내지 0.006 mm로 구성될 수 있다. 보다 구체적으로, 제1 용접 라인(W1)과 제2 용접 라인(W2) 사이의 간격은 0.003mm 내지 0.004mm로 구성될 수 있다.For example, the spacing of the weld lines constituting the tornado may be comprised between 0.002 mm and 0.006 mm. More specifically, the distance between the first welding line W1 and the second welding line W2 may be comprised between 0.003 mm and 0.004 mm.
다른 예로, 용접 스팟의 직경, 이를테면 토네이도의 최대 폭은, 1.5mm 내지 3mm로 구성될 수 있다. 보다 구체적으로, 도 5의 구성에서, 제1 용접 라인(W1)의 외측 단부(o1)와 제2 용접 라인(W2)의 외측 단부(o2) 사이의 거리는 2.0mm 내지 2.5mm로 구성될 수 있다.As another example, the diameter of the weld spot, such as the maximum width of the tornado, may be comprised between 1.5 mm and 3 mm. 5, the distance between the outer end o1 of the first welding line W1 and the outer end o2 of the second welding line W2 may be comprised between 2.0 mm and 2.5 mm .
또 다른 예로, 하나의 토네이도에서 내측 단부 간 거리는, 0.15 mm 내지 0.25mm로 구성될 수 있다. 보다 구체적으로, 도 5의 구성에서, 제1 용접 라인(W1)의 내측 단부(i1)와 제2 용접 라인(W2)의 내측 단부(i2) 사이의 거리는 0.2mm로 구성될 수 있다. 이러한 구성에 의하면, 내측 단부 부근에서 과용접으로 인해 용접부에 크랙이 생성되거나 약용접으로 인해 용접력이 저하되는 것을 방지할 수 있다.As another example, the medial end-to-end distance in one tornado may be comprised between 0.15 mm and 0.25 mm. More specifically, in the configuration of Fig. 5, the distance between the inner end i1 of the first welding line W1 and the inner end i2 of the second welding line W2 may be 0.2 mm. According to such a configuration, it is possible to prevent a crack from being generated in the welded portion due to over-welding in the vicinity of the inner end portion or deterioration of the welding force due to the weak welding.
상기와 같은 여러 설정 파라미터에 대하여, 적어도 일부 파라미터는 다른 파라미터의 설정값에 의존하는 형태로 구성될 수 있다.With respect to the various setting parameters as described above, at least some of the parameters may be configured to be dependent on the setting values of the other parameters.
예를 들어, 하나의 용접 스팟을 구성하는 토네이도의 직경이 2.5mm인 경우, 용접 라인의 간격은 0.0035mm 이상 0.0045mm 이하일 수 있다. 이를테면, 이때 용접 라인의 간격은, 0.004mm가 적합할 수 있다. 만일, 이러한 직경을 갖는 토네이도 구성에서, 용접 라인의 간격이 0.003mm인 경우 과용접으로 인한 용접강도 저하 현상이 발생할 수 있다. 반대로, 이러한 직경을 갖는 토네이도 구성에서, 용접 라인의 간격이 0.005mm인 경우, 약용접 현상이 발생할 수 있다.For example, if the diameter of the tornadoes constituting one weld spot is 2.5 mm, the spacing of the weld lines may be 0.0035 mm or more and 0.0045 mm or less. For example, the interval of the welding line at this time may be 0.004 mm. In a tornado configuration having such a diameter, if the interval of the welding lines is 0.003 mm, the welding strength may be lowered due to over-welding. Conversely, in a tornado configuration having such a diameter, if the interval of the welding line is 0.005 mm, weak welding phenomenon may occur.
반면, 하나의 용접 스팟을 구성하는 토네이도의 직경이 2.0mm인 경우, 용접 라인의 간격은 0.0025mm 이상 0.0035mm 이하일 수 있다. 이를테면, 이때 용접 라인의 간격은, 0.003mm가 적합할 수 있다. 만일, 이러한 직경을 갖는 토네이도 구성에서, 용접 라인의 간격이 0.004mm인 경우 약용접으로 인한 버스바 비용접 문제가 발생할 수 있다. 반대로, 이러한 직경을 갖는 토네이도 구성에서, 용접 라인의 간격이 0.002mm인 경우, 과용접 현상으로 용접 강도가 저하되는 문제점이 발생할 수 있다.On the other hand, when the diameter of the tornado constituting one welding spot is 2.0 mm, the interval of the welding line may be 0.0025 mm or more and 0.0035 mm or less. For example, the interval of the welding line at this time may be 0.003 mm. If, in such a diameter tornado configuration, the spacing of the weld lines is 0.004 mm, there may be a bus bar weld failure due to weak welding. On the contrary, in the case of a tornado configuration having such a diameter, when the interval of the welding lines is 0.002 mm, the welding strength may be lowered due to over-contact.
한편, 도 5를 비롯한, 이하의 여러 도면에서는, 제1 용접 라인(W1)과 제2 용접 라인(W2)을 구분하기 위해 두 라인의 두께를 다르게 표시하였으나, 이는 설명의 편의를 위한 것일 뿐, 두 라인의 용접 두께가 달라야 함을 의미하는 것은 아니다.5, in order to distinguish the first welding line W1 from the second welding line W2, the thicknesses of the two lines are different from each other. However, It does not mean that the weld thickness of the two lines should be different.
또한, 나선 형태의 복수의 용접 라인이 하나의 용접 스팟(W)을 구성하는 형태에서, 복수의 용접 라인의 각 외측 단부, 즉 복수의 외측 단부는, 하나의 중심선을 기준으로 서로 반대편에 위치하도록 구성될 수 있다.Further, in a form in which a plurality of welding lines in the form of a spiral constitute one welding spot (W), each of the outer ends, i.e., the plurality of outer ends, of the plurality of welding lines are positioned opposite to each other with respect to one center line Lt; / RTI >
예를 들어, 도 5의 구성을 참조하면, 용접 스팟(W)의 중심점(p)을 기준으로, 용접 스팟을 4개의 사분면으로 구분할 수 있다. 여기서, 용접 스팟(W)의 중심점(p)은, 용접 스팟(W)의 중앙에 위치한 점으로서, 이를테면 2개의 용접 라인의 외측 단부인 o1과 o2 사이의 거리를 지름으로 하고 o1 및 o2를 지나는 원의 중심점이라 할 수 있다. 그리고, 도 5의 c11 및 c12로 표시된 바와 같이, 용접 스팟(W)의 중심점(p)을 지나면서, 서로 직교하는 2개의 직선이 그려질 수 있다. 이를테면, 도 5의 Y축에 평행하면서 중심점 p를 지나는 직선이 c11, 도 5의 Z축에 평행하면서 중심점 p를 지나는 직선이 c12일 수 있다. 그러면, 이러한 2개의 직선(c11, c12)에 의해 구분되는 4개의 영역이 곧 서로 다른 사분면이라 할 수 있다. 보다 구체적으로, 도 5에 도시된 바를 살펴보면, 2개의 직선(c11, c12)에 의해 우측 상단에 위치하는 영역을 제1 사분면(Q1), 좌측 상단에 위치하는 영역을 제2 사분면(Q2), 좌측 하단에 위치하는 영역을 제3 사분면(Q3), 그리고 우측 하단에 위치하는 영역을 제4 사분면(Q4)이라 할 수 있다.For example, referring to the configuration of FIG. 5, the weld spot can be divided into four quadrants based on the center point p of the weld spot W. Here, the center point p of the weld spot W is a point located at the center of the weld spot W, for example, the distance between o1 and o2, which is the outer end of the two weld lines, It is the center point of the circle. Then, as indicated by c11 and c12 in Fig. 5, two straight lines perpendicular to each other can be drawn, passing through the center point p of the weld spot W. For example, a straight line passing through the center point p in parallel with the Y axis in Fig. 5 may be c11, a straight line parallel to the Z axis in Fig. 5 and passing the center point p may be c12. Then, the four regions separated by the two straight lines c11 and c12 may be different quadrants. More specifically, referring to FIG. 5, a region located at the right upper end by the two straight lines c11 and c12 is referred to as a first quadrant Q1, a region located at the upper left end is referred to as a second quadrant Q2, The region located at the lower left corner is referred to as the third quadrant Q3, and the region located at the lower right corner may be referred to as the fourth quadrant Q4.
이와 같이, 용접 스팟(W)이 4개의 사분면으로 분할될 때, 제1 용접 라인(W1)의 외측 단부(o1)와 제2 용접 라인(W2)의 외측 단부(o2)는, 서로 다른 사분면에 위치하도록 구성될 수 있다. 특히, 제1 용접 라인(W1)의 외측 단부(o1)와 제2 용접 라인(W2)의 외측 단부(o2)는, 인접하지 않고 서로 반대되는 사분면에 위치하도록 구성될 수 있다. 예를 들어, 도 5에 도시된 바와 같이, 제1 용접 라인(W1)의 외측 단부(o1)가 제3 사분면(Q3)에 위치하는 경우, 제2 용접 라인(W2)의 외측 단부(o2)는 제3 사분면과 인접하지 않으면서 서로 반대 측에 위치하는 제1 사분면(Q1)에 위치하도록 구성될 수 있다. 만일, 2개의 용접 라인(W1, W2)의 외측 단부 중 어느 하나, 이를테면 o1이 직선 c12에 위치하는 경우, 다른 하나의 외측 단부, 이를테면 o2 역시 직선 c12 상에 위치할 수도 있다. 다만, 이 경우, 2개의 외측 단부인 o1과 o2는 직선 c11을 기준으로 서로 반대되는 측에 위치할 수 있다.Thus, when the welding spot W is divided into four quadrants, the outer end o1 of the first welding line W1 and the outer end o2 of the second welding line W2 are located in different quadrants . ≪ / RTI > In particular, the outer end o1 of the first welding line W1 and the outer end o2 of the second welding line W2 may be configured to be located in quadrants that are not adjacent but opposite to each other. 5, when the outer end o1 of the first welding line W1 is located in the third quadrant Q3, the outer end o2 of the second welding line W2 is located at the second quadrant Q3, Can be configured to be located in the first quadrant (Q1), which is not adjacent to the third quadrant but located on the opposite side from each other. If one of the outer ends of the two welding lines W1, W2, such as o1, is located at the straight line c12, the other outer end, such as o2, may also be located on the straight line c12. However, in this case, the two outer ends o1 and o2 may be located on opposite sides with respect to the straight line c11.
본 발명의 이러한 구성에 의하면, 토네이도 형태의 용접 스팟(W)의 용접 강도를 보다 향상시킬 수 있다. 특히, 하나 이상의 용접 라인의 단부 부근에서 발생할 수 있는 피로도(fatigue)가 특정 부분에 집중되지 않고 분산되도록 함으로써 용접 성능이 더욱 향상되도록 할 수 있다.According to this configuration of the present invention, it is possible to further improve the welding strength of the tornado-shaped welding spot W. In particular, the fatigue that may occur in the vicinity of the end of one or more weld lines may be distributed rather than being concentrated in a particular portion, thereby further improving the welding performance.
또한, 상기 용접 스팟(W)은, 복수의 용접 라인의 각 내측 단부를 연결하는 직선 및 각 외측 단부를 연결하는 직선이 서로 평행하도록 구성될 수 있다. 이에 대해서는, 도 6을 참조하여 보다 구체적으로 설명하도록 한다.The welding spot W may be configured such that a straight line connecting each inner end of the plurality of welding lines and a straight line connecting the respective outer ends are parallel to each other. This will be described in more detail with reference to FIG.
도 6은, 본 발명의 다른 실시예에 따른 용접 스팟의 토네이도 형태를 개략적으로 나타내는 도면이다. 예를 들어, 도 6은, 도 4의 B1 부분에 적용될 수 있는 다른 실시 구성이라 할 수 있다. 이하에서는, 앞선 실시예에 대한 설명이 동일 또는 유사하게 적용될 수 있는 부분에 대해서는 상세한 설명을 생략하고, 차이점이 있는 부분을 위주로 설명한다. 그리고, 이러한 설명 방식은, 이하의 다른 여러 실시예에 대해서도 마찬가지라 할 수 있다.6 is a diagram schematically illustrating a tornado shape of a welding spot according to another embodiment of the present invention. For example, FIG. 6 is another implementation that can be applied to the portion B1 of FIG. Hereinafter, detailed description of the parts that can be applied to the same or similar parts in the description of the preceding embodiments will be omitted, and differences will be mainly described. This explanation method is also applicable to the following various other embodiments.
도 6을 참조하면, 제1 용접 라인(W1)의 외측 단부(o1)와 제2 용접 라인(W2)의 외측 단부(o2)를 연결하는 직선은 c2라 할 수 있다. 또한, 제1 용접 라인(W1)의 내측 단부(i1)와 제2 용접 라인(W2)의 내측 단부(i2)를 연결하는 직선 역시 c2라 할 수 있다. 즉, 복수의 용접 라인의 외측 단부(o1, o2)를 연결하는 직선과 복수의 용접 라인의 내측 단부(i1, i2)를 연결하는 직선이 이루는 각도는 0으로서, 양 직선이 서로 평행한 형태로 구성될 수 있다. 더 나아가, 복수의 용접 라인에 대해 외측 단부(o1, o2)를 연결하는 직선과 내측 단부(i1, i2)를 연결하는 직선은 동일한 하나의 직선(c2)일 수 있다. 즉, 복수의 용접 라인의 외측 단부와 내측 단부는 모두 하나의 직선상에 위치하도록 토네이도가 구성될 수 있다.Referring to FIG. 6, the straight line connecting the outer end o1 of the first welding line W1 and the outer end o2 of the second welding line W2 may be c2. The straight line connecting the inner end i1 of the first welding line W1 and the inner end i2 of the second welding line W2 may also be c2. That is, the angle formed by the straight line connecting the outer ends o1 and o2 of the plurality of welding lines and the straight line connecting the inner ends i1 and i2 of the plurality of welding lines is 0, and both straight lines are parallel to each other Lt; / RTI > Furthermore, the straight line connecting the outer ends o1, o2 to the plurality of welding lines and the straight line connecting the inner ends i1, i2 may be the same straight line c2. That is, the tornado can be configured such that both the outer end and the inner end of the plurality of welding lines are located on one straight line.
본 발명의 이러한 구성에 의하면, 용접 성능이 더욱 향상될 수 있다. 특히, 이러한 토네이도 용접 스팟(W)의 외측 단부와 내측 단부 사이를 연결하는 직선이 인장이 진행되는 방향에서 수직으로 형성되는 경우, 단부의 피로도가 저하될 수 있다. 예를 들어, 도 6의 구성에서, 인장이 주로 좌우 방향으로 형성되는 상황에서, 용접 스팟(W)의 외측 단부와 내측 단부 사이를 연결하는 직선이 모두 상하 방향으로 형성되는 경우, 용접 라인의 단부로 가해지는 스트레스가 완화될 수 있다.According to this configuration of the present invention, the welding performance can be further improved. Particularly, when the straight line connecting between the outside end and the inside end of the tornado welding spot W is formed vertically in the direction in which the tensile proceeds, the fatigue of the end portion may be lowered. For example, in the configuration of Fig. 6, in the case where the tensile is mainly formed in the left-right direction, when all of the straight lines connecting the outer end and the inner end of the weld spot W are formed in the vertical direction, The stress exerted on the user can be mitigated.
한편, 상기 실시예와 같이, 다수의 용접 라인, 이를테면 2개의 용접 라인에 의해 1개의 토네이도가 형성되도록 용접 스팟(W)이 구성되는 경우, 각 용접 라인은, 외측 단부에서 내측 단부 방향으로 레이저 조사 경로가 이동하거나, 내측 단부에서 외측 단부 방향으로 레이저 조사 경로가 이동함으로써 형성될 수 있다. On the other hand, in the case where the welding spot W is constituted such that one tornado is formed by a plurality of welding lines, for example, two welding lines as in the above embodiment, each welding line is irradiated with a laser beam in the inner- Or by moving the laser irradiation path from the inner end to the outer end direction.
예를 들어, 도 6의 구성에서, 제1 용접 라인(W1) 및 제2 용접 라인(W2)은 외측 단부에서 내측 단부 방향으로, 또는 내측 단부에서 외측 단부 방향으로 레이저가 조사되는 형태로 형성될 수 있다. For example, in the configuration of Fig. 6, the first welding line W1 and the second welding line W2 are formed in such a manner that the laser is irradiated in the inner end direction from the outer end portion, or in the outer end direction from the inner end portion .
특히, 상대적으로 먼저 형성되는 용접 라인은 외측 단부에서 내측 단부 방향으로 레이저가 조사된 형태로 구성되고, 상대적으로 늦게 형성되는 용접 라인은 내측 단부에서 외측 단부 방향으로 레이저가 조사된 형태로 구성될 수 있다.Particularly, the welding line relatively formed first is formed in a form in which the laser is irradiated in the direction from the outer end to the inner end, and the welding line formed relatively late can be configured in a form in which the laser is irradiated from the inner end to the outer end have.
예를 들어, 도 6의 구성에서, 제1 용접 라인(W1)이 제2 용접 라인(W2)보다 먼저 형성된다면, 제1 용접 라인(W1)은, 화살표 d1으로 표시된 바와 같이, 외측 단부(o1)에서 내측 단부(i1) 방향으로 레이저 조사 경로가 이동되는 형태로 구성될 수 있다. 그리고, 제2 용접 라인(W2)은, 화살표 d2로 표시된 바와 같이, 내측 단부(i2)에서 외측 단부(o2) 방향으로 레이저 조사 경로가 이동되는 형태로 구성될 수 있다.6, if the first welding line W1 is formed prior to the second welding line W2, the first welding line W1 is located at the outer end o1 And the laser irradiation path is moved in the direction of the inner end portion i1. The second welding line W2 may be configured such that the laser irradiation path is moved from the inner end i2 to the outer end o2 as indicated by an arrow d2.
본 발명의 이러한 구성에 의하면, 제1 용접 라인(W1)의 형성을 위한 레이저 조사가 끝나는 부분에 인접하여 다시 제2 용접 라인(W2)의 형성을 위한 레이저 조사가 시작되기 때문에, 제1 용접 라인(W1)과 제2 용접 라인(W2)의 형성을 위한 레이저 조사 시간이 단축되고, 공정성이 개선될 수 있다.According to this configuration of the present invention, since the laser irradiation for forming the second welding line W2 is started adjacent to the portion where the laser irradiation for forming the first welding line W1 ends, The laser irradiation time for forming the first welding line W1 and the second welding line W2 can be shortened and the processability can be improved.
또한, 제1 용접 라인(W1)의 외측 단부 부근에서는 전극 리드에 충분한 열이 전달되지 못해 용접 강도가 상대적으로 약해질 수 있으나, 제2 용접 라인(W2) 형성 과정에서 제2 용접 라인(W2)의 외측 단부(o2) 부근에는 충분한 열이 공급될 수 있으므로, 용접 스팟은 내측에서 외측에 이르기까지 전체적으로 용접 강도가 균일하게 확보될 수 있다. 따라서, 용접 스팟의 용접성이 더욱 향상될 수 있다.In addition, in the vicinity of the outer end of the first welding line W1, sufficient heat is not transferred to the electrode lead, so that the welding strength may be relatively weak. However, in the process of forming the second welding line W2, Sufficient heat can be supplied to the vicinity of the outer end portion o2 of the welding spot, so that the welding spot can be uniformly secured as a whole from the inside to the outside. Therefore, the weldability of the weld spot can be further improved.
또한, 상기 용접 스팟은, 복수의 용접 라인의 내측 단부가 서로 연결되도록 구성될 수 있다. 이에 대해서는, 도 7을 참조하여 보다 구체적으로 설명하도록 한다.Further, the welding spot may be configured so that the inner ends of the plurality of welding lines are connected to each other. This will be described in more detail with reference to FIG.
도 7은, 본 발명의 또 다른 실시예에 따른 용접 스팟의 토네이도 형태를 개략적으로 나타내는 도면이다. 예를 들어, 도 7은, 도 4의 B1 부분에 적용될 수 있는 또 다른 실시 구성이라 할 수 있다.7 is a schematic representation of a tornado shape of a weld spot in accordance with another embodiment of the present invention. For example, FIG. 7 may be another implementation configuration that may be applied to the portion B1 of FIG.
도 7을 참조하면, 나선 형태로 형성된 2개의 용접 라인(W1, W2)이 구비되어 하나의 토네이도를 형성하되, 2개의 토네이도는, B4로 표시된 부분과 같이, 내측 단부가 서로 연결될 수 있다. 즉, 도 7에서, 제1 용접 라인(W1)과 제2 용접 라인(W2)은 각각 나선 형태로 형성되어, 서로 다른 외측 단부(o1, o2)를 구비하되, 내측 단부는 별도로 분리되지 않고 상호 연결된 형태로 구성될 수 있다. Referring to FIG. 7, two welding lines W1 and W2 formed in a spiral shape are provided to form one tornado, and two tornadoes can be connected to each other at their inner ends, such as a portion indicated by B4. 7, the first welding line W1 and the second welding line W2 are each formed in a spiral shape and have different outer ends o1 and o2, And can be configured in a connected form.
본 발명의 이러한 구성에 의하면, 복수의 용접 라인은 내측 단부를 별도로 구비하지 않는다고 할 수 있다. 따라서, 내측 단부 부근에서 피로도가 생성되어 크랙 등이 발생하는 것을 방지할 수 있다. 또한, 복수의 용접 라인, 특히 2개의 용접 라인을 형성하는 과정이 연속적으로 이루어질 수 있기 때문에, 용접 공정이 보다 원활하게 이루어질 수 있다.According to this configuration of the present invention, it is possible to say that a plurality of welding lines do not have the inner end separately. Therefore, fatigue is generated in the vicinity of the inner end portion, and occurrence of cracks or the like can be prevented. In addition, since the process of forming a plurality of welding lines, particularly two welding lines, can be performed continuously, the welding process can be performed more smoothly.
또한 바람직하게는, 상기 용접 스팟(W)은, 하나의 전극 리드(111)에 대하여 다수 구비될 수 있다.Also, it is preferable that a plurality of the welding spots W are provided for one electrode lead 111.
예를 들어, 도 4에 도시된 바와 같이, 외부, 즉 전면으로 노출된 전극 리드(111)는, 후방에 위치하여 함께 적층된 다른 전극 리드 및/또는 버스바(200)와 다수의 용접 스팟에 의해 용접될 수 있다. 이때, 다수의 용접 스팟(W)은, 각각 앞서 설명한 바와 같이 토네이도 형태로 구성되며, 상호 간 소정 거리 이격되게 배치될 수 있다.For example, as shown in FIG. 4, the electrode leads 111 exposed to the outside, that is, the front face, are located at the rear of the other electrode leads and / or the bus bar 200 and the plurality of welding spots As shown in Fig. At this time, the plurality of welding spots W are formed in a tornado shape as described above, and can be arranged to be spaced apart from each other by a predetermined distance.
특히, 하나의 전극 리드에 대하여 다수의 용접 스팟(W)은, 상하 방향(도면의 Z축 방향)으로 배치될 수 있다. 보다 구체적으로, 다수의 이차 전지가 좌우 방향(도면의 Y축 방향)으로 배치될 때, 각 이차 전지의 전극 리드는, 전후 방향(도면의 X축 방향)으로 적층된 형태로 상호 접촉될 수 있다. 이때, 전극 리드와 전극 리드 사이, 및/또는 전극 리드와 버스바 사이의 접촉 부분은, 장변이 상하 방향(도면의 Z축 방향)으로 형성되고 단변이 좌우 방향(도면의 Y축 방향)으로 형성되는, 대략 직사각형 모양으로 구성될 수 있다. 이 경우, 다수의 용접 스팟은, 이러한 직사각형 모양의 접촉 부분에 있어서, 장변 방향, 다시 말해 상하 방향으로 배열되는 형태로 구성될 수 있다. 즉, 용접 스팟은, 전극 리드의 전면 노출 부분의 길이 방향을 따라 소정 거리 이격되게 다수 배치되도록 구성될 수 있다.In particular, a plurality of welding spots W with respect to one electrode lead can be arranged in the vertical direction (Z-axis direction in the figure). More specifically, when a plurality of secondary batteries are arranged in the lateral direction (the Y-axis direction in the figure), the electrode leads of each secondary battery can be mutually contacted in a laminated form in the front-rear direction . At this time, the contact portion between the electrode lead and the electrode lead and / or between the electrode lead and the bus bar is formed in the vertical direction (Z-axis direction in the figure) and the short side is formed in the horizontal direction , Which is substantially rectangular in shape. In this case, the plurality of welding spots may be arranged in the long-side direction, that is, in the vertical direction, in such a rectangular contact portion. That is, the welding spots may be arranged to be spaced a predetermined distance along the longitudinal direction of the front exposed portion of the electrode lead.
본 발명의 이러한 구성에 의하면, 전극 리드와 전극 리드 사이 및/또는 전극 리드와 버스바 사이의 결합력이 더욱 향상될 수 있다. 특히, 각각의 용접 스팟은 토네이도 형태로 형성되어 그 자체로서 용접성이 우수할 뿐만 아니라, 다수의 용접 스팟이 서로 소정 거리 이격됨으로써 용접성이 더욱 안정적으로 유지될 수 있다. 즉, 다수의 용접 스팟은 서로 분리되어 있기 때문에, 하나의 용접 스팟(W)에서 크랙 등이 발생하더라도, 이러한 크랙은 다른 용접 스팟(W)까지 성장하기 어렵다. 따라서, 전극 리드의 용접 상태가 안정적으로 유지될 수 있다. 더욱이, 배터리 모듈이 진동이나 충격에 자주 노출된다 하더라도, 이러한 진동이나 충격으로 인해 크랙이 계속적으로 성장하는 것을 방지하여, 전극 리드의 전기적 연결 상태에 불량이 발생하는 것을 예방할 수 있다.According to this configuration of the present invention, the coupling force between the electrode leads and the electrode leads and / or between the electrode leads and the bus bars can be further improved. In particular, each of the welding spots is formed in a tornado shape, and not only is the welding performance excellent as it is, but also a plurality of welding spots are spaced apart from each other by a predetermined distance, so that the weldability can be more stably maintained. That is, since a plurality of welding spots are separated from each other, even if a crack or the like occurs in one welding spot W, such a crack is difficult to grow up to another welding spot W. Therefore, the welding state of the electrode leads can be stably maintained. Furthermore, even if the battery module is frequently exposed to vibration or impact, it is possible to prevent the crack from continuing to grow due to such vibration or impact, thereby preventing the occurrence of defective electrical connection of the electrode leads.
또한, 상기 구성에 의하면, 전극 리드 등에 하중이 인가되는 경우, 다수의 용접 스팟으로 인가 하중이 분산됨으로써, 각 용접 스팟의 용접 상태가 보다 안정적으로 유지될 수 있다.According to the above configuration, when a load is applied to the electrode lead or the like, the applied load is distributed to a plurality of welding spots, so that the welding state of each welding spot can be more stably maintained.
뿐만 아니라, 도 3 및 도 4에 도시된 바와 같이, 이차 전지가 좌우 방향으로 배열되어 전극 리드 역시 좌우 방향으로 배열되는 구성의 경우, 충격이나 진동 등에 의해 힘이 주로 가해지는 방향은, 전극 리드의 배열 방향인 좌우 방향(도면의 Y축 방향)일 수 있다. 이때, 상기 구성과 같이, 용접 스팟이 하나의 전극 리드에 대하여 상하 방향(도면의 Z축 방향)으로 배치되면, 힘이 가해지는 방향에 대략 직교하는 방향으로 용접 스팟이 다수 배치된다고 할 수 있다. 따라서, 외부 힘에 대한 다수의 용접 스팟의 용접 상태가 보다 안정적으로 유지될 수 있다.3 and 4, in the case of a configuration in which the secondary batteries are arranged in the left-right direction and the electrode leads are also arranged in the left-right direction, the direction in which the force is mainly applied by impact, vibration, (Y-axis direction in the figure) that is an arrangement direction. At this time, if the welding spots are arranged in the vertical direction (the Z-axis direction in the figure) with respect to one electrode lead as in the above-described configuration, a plurality of welding spots are arranged in a direction substantially perpendicular to the direction in which the force is applied. Thus, the welding state of a plurality of welding spots with respect to an external force can be more stably maintained.
더욱이, 상기 구성에 있어서, 하나의 전극 리드에 구비된 다수의 용접 스팟은, 외측 단부가 하나의 직선 상에 위치하도록 구성될 수 있다. 이에 대해서는, 도 8을 참조하여 보다 구체적으로 설명하도록 한다.Furthermore, in the above configuration, the plurality of welding spots provided in one electrode lead can be configured such that the outer end is located on one straight line. This will be described in more detail with reference to Fig.
도 8은, 본 발명의 일 실시예에 따른 배터리 모듈에서, 전극 리드에 구비된 다수의 용접 스팟의 구성을 개략적으로 나타내는 도면이다. 예를 들어, 도 8은, 도 4의 B2 부분에 대한 확대 구성의 일례라 할 수 있다.8 is a view schematically showing a configuration of a plurality of welding spots provided in an electrode lead in a battery module according to an embodiment of the present invention. For example, FIG. 8 is an example of an enlarged configuration for the portion B2 in FIG.
도 8을 참조하면, 전극 리드에 상하 방향(도면의 Z축 방향)으로 다수, 즉 3개의 용접 스팟(W1)이 서로 소정 거리 이격된 형태로 형성될 수 있다. 이때, 상대적으로 가장 상부에 위치한 용접 스팟을 제1 용접 스팟(Wa)이라 하고, 하부 방향으로 순차적으로 제2 용접 스팟(Wb) 및 제3 용접 스팟(Wc)이라 할 수 있다. 그리고, 이러한 3개의 용접 스팟은 각각, 2개의 나선, 즉 2개의 용접 라인으로 구성된 토네이도 형태로 구성될 수 있다.Referring to FIG. 8, a large number of the welding spots W1 may be formed on the electrode leads in the vertical direction (the Z-axis direction in the figure). At this time, the welding spots located at the uppermost position are referred to as a first welding spot Wa and the second welding spot Wb and the third welding spot Wc are sequentially referred to as a downward direction. And these three weld spots can each be configured in the form of a tornado consisting of two spirals, i.e. two weld lines.
이러한 구성에서, 제1 용접 스팟의 제1 용접 라인(Wa1) 및 제2 용접 라인(Wa2)의 각 외측 단부, 제2 용접 스팟의 제1 용접 라인(Wb1) 및 제2 용접 라인(Wb2)의 각 외측 단부, 제3 용접 스팟의 제1 용접 라인(Wc1) 및 제2 용접 라인(Wc2)의 외측 단부는 모두, c4로 표시된 하나의 직선상에 위치하도록 구성될 수 있다. 즉, 이 경우, 3개의 용접 스팟에 구비된 6개의 외측 단부는, 모두 동일한 직선 상에 위치하도록 구성될 수 있다.In this configuration, the outer end of each of the first welding line Wa1 and the second welding line Wa2 of the first welding spot, the first welding line Wb1 of the second welding spot and the second welding line Wb2 of the second welding spot Each outer end, the first welding line Wc1 of the third welding spot, and the outer end of the second welding line Wc2 may all be configured to lie on one straight line labeled c4. That is, in this case, the six outer ends provided in the three welding spots can be configured to be all located on the same straight line.
본 발명의 이러한 구성에 의하면, 다수의 용접 스팟에 의한 피용접물의 용접력이 보다 향상될 수 있다. 특히, 상기 실시예와 같이, 이차 전지가 좌우 방향으로 배열되는 구성의 경우, 진동이나 충격에 의한 힘, 즉 인장력은 좌우 방향으로 발생할 수 있다. 이때, 토네이도 형태로 형성된 각 용접 스팟의 외측 단부가 하나의 직선상에 위치하고, 이러한 직선이 이러한 인장력의 방향에 대략 직교하는 방향으로 구성되면, 외측 단부에 형성되는 피로도에 의해 용접력이 약해지는 것을 방지하거나 감소시킬 수 있다.According to this configuration of the present invention, the welding power of the workpieces by a plurality of welding spots can be further improved. Particularly, in the case where the secondary battery is arranged in the left-right direction as in the above-described embodiment, the force due to vibration or impact, that is, the tensile force can be generated in the left-right direction. At this time, if the outer ends of the respective welding spots formed in a tornado shape are located on one straight line and these straight lines are formed in a direction substantially perpendicular to the direction of the tensile force, the weld strength is weakened by the fatigue formed at the outer end Prevention or reduction.
한편, 상기 용접 스팟(W)은, 앞서 설명한 바와 같이, 전극 리드와 전극 리드 사이, 및/또는 전극 리드와 버스바 사이를 용접하는 형태로 구성될 수 있다.On the other hand, the welding spot W may be configured to be welded between the electrode lead and the electrode lead, and / or between the electrode lead and the bus bar, as described above.
특히, 상기 용접 스팟(W)은, 다수의 전극 리드와 1개의 버스바를 함께 용접하도록 구성될 수 있다. 이에 대해서는, 도 9를 참조하여 보다 구체적으로 설명하도록 한다.In particular, the welding spot W may be configured to weld a plurality of electrode leads and a bus bar together. This will be described in more detail with reference to FIG.
도 9는, 본 발명의 일 실시예에 따른 배터리 모듈에서 전극 리드와 버스바 사이의 용접 구성을 개략적으로 나타내는 단면도이다. 예를 들어, 도 9는, 도 4의 B3-B3'선에 대한 단면 구성의 일례라 할 수 있다. 다만, 도 9에서는, 설명의 편의를 위해, 전극 리드의 일부와 버스바만 도시되도록 한다.9 is a cross-sectional view schematically showing a welding configuration between an electrode lead and a bus bar in a battery module according to an embodiment of the present invention. For example, FIG. 9 is an example of a sectional configuration taken along line B3-B3 'in FIG. In Fig. 9, for convenience of explanation, only a part of the electrode lead and a bus bar are shown.
도 9를 참조하면, 다수의 전극 리드, 즉 2개의 전극 리드(111)가 좌우 방향(도면의 Y축 방향)으로 서로 겹쳐진 상태에서 일부분이 절곡되고, 절곡된 단부가 버스바(200)의 전면(도 9의 상면)에 부착된다. 이 경우, 2개의 전극 리드(111)와 1개의 버스바(200)가 전후 방향(도면의 X축 방향)으로 적층된다고 할 수 있다.9, a plurality of electrode leads, that is, two electrode leads 111 are overlapped with each other in the left-right direction (Y-axis direction in the figure) (Upper surface in Fig. 9). In this case, it can be said that the two electrode leads 111 and one bus bar 200 are laminated in the front-rear direction (X-axis direction in the drawing).
이러한 구성에 있어서, 상호 적층된 2개의 전극 리드(111)와 1개의 버스바(200)는, 하나 이상의 용접 스팟(W)에 의해 용접될 수 있다. 더욱이, 도 3 및 도 4에 도시된 바와 같이, 상호 적층된 2개의 전극 리드(111)와 1개의 버스바(200)는, 다수, 이를테면 6개 내지 8개의 용접 스팟(W)에 의해 상호 용접될 수 있다.In this configuration, the two electrode leads 111 and one bus bar 200 stacked one upon the other can be welded by one or more welding spots W. 3 and 4, two mutually stacked electrode leads 111 and one bus bar 200 are welded together by a plurality, such as six to eight weld spots W. [ .
이때, 각 용접 스팟은, 도 9에 도시된 바와 같이, 제1 용접 라인(W1) 및 제2 용접 라인(W2)을 구비할 수 있는데, 2개의 용접 라인은, 각각 나선 형태로 형성될 수 있다. 예를 들어, 각 용접 스팟은, 도 5 내지 도 8에 도시된 용접 스팟 형태 중 어느 하나의 형태로 구성될 수 있다. 따라서, 2개의 전극 리드와 버스바가 결합된 구성의 한 단면에서는, 도 9에 도시된 바와 같이, 다수의 용접 라인에 의한 용접 부분이 형성될 수 있다.At this time, each welding spot may have a first welding line W1 and a second welding line W2, as shown in Fig. 9, wherein each of the two welding lines may be formed in a spiral shape . For example, each weld spot may be configured in any one of the weld spot shapes shown in FIGS. 5-8. Therefore, in one cross section of the configuration in which the two electrode leads and the bus bar are combined, as shown in Fig. 9, a welding portion by a plurality of welding lines can be formed.
상기와 같은 구성에서, 다수의 전극 리드(111)는 서로 동일 재질이고, 버스바(200)는 이러한 전극 리드와 다른 재질로 구성될 수 있다. 예를 들어, 도 9의 실시예에서, 2개의 전극 리드(111)는 알루미늄 재질로 구성되고, 1개의 버스바(200)는 구리 재질로 구성될 수 있다. 특히, 다수의 이차 전지가 전기적으로 병렬로 연결될 때 이와 같은 구성이 구비될 수 있다.In the above configuration, the plurality of electrode leads 111 are made of the same material, and the bus bar 200 may be made of a material different from the electrode leads. For example, in the embodiment of FIG. 9, the two electrode leads 111 may be made of aluminum and one bus bar 200 may be made of copper. In particular, when a plurality of secondary batteries are electrically connected in parallel, such a configuration may be provided.
이처럼, 상호 결합 고정되는 전극 리드와 버스바가 서로 다른 재질로 구성될 때, 본 발명과 같이, 토네이도 형태로 구성된 하나 이상의 용접 스팟에 의해 상호 용접되도록 구성되는 것이 좋다. 이 경우, 다수의 전극 리드와 버스바 사이의 용접성이 안정적으로 확보될 수 있다. 다만, 이러한 전극 리드와 버스바의 재질은 전지나 배터리 팩의 종류, 배터리 팩이 적용되는 장치의 특성 등 다양한 요소에 따라 다양한 재질로 구성될 수 있음은 물론이다. 예를 들어, 2개의 전극 리드, 즉 양극 리드와 음극 리드는 서로 다른 재질로 구성될 수 있다. 이 경우, 하나의 전극 리드와 버스바는 서로 동일한 재질로 구성될 수도 있다. 또는, 2개의 전극 리드와 버스바가 모두, 서로 동일한 재질로 구성될 수도 있다.When the electrode leads and the bus bars, which are mutually coupled and fixed to each other, are made of different materials, it is preferable that they are welded to each other by one or more welding spots formed in a tornado shape as in the present invention. In this case, the weldability between a plurality of electrode leads and the bus bar can be stably secured. However, it is needless to say that the material of the electrode lead and the bus bar may be made of various materials according to various factors such as the type of the battery, the battery pack, and the characteristics of the device to which the battery pack is applied. For example, the two electrode leads, that is, the positive electrode lead and the negative electrode lead, may be made of different materials. In this case, one electrode lead and the bus bar may be made of the same material. Alternatively, both of the two electrode leads and the bus bar may be made of the same material.
한편, 도 9에서는 2개의 전극 리드와 1개의 버스바가 상호 적층되어 용접되는 형태로 도시되어 있으나, 이는 일례에 불과할 뿐, 3개 이상의 전극 리드와 1개의 버스바가 상호 적층된 상태에서 용접될 수도 있다. 그리고, 이때에도, 앞서 설명한 바와 같은 토네이도 형태의 용접 스팟이 적용될 수 있다.In FIG. 9, two electrode leads and one bus bar are shown as being welded to each other. However, this is merely an example, and three or more electrode leads and one bus bar may be welded together . Also, at this time, a welding spot of a tornado shape as described above can be applied.
또한, 바람직하게는, 상기 전극 리드는, 내측 방향으로 오목하게 형성된 오목부를 구비하고, 용접 스팟은 이러한 오목부에 적어도 일부가 위치하도록 구성될 수 있다. 이에 대해서는, 도 10을 참조하여 보다 구체적으로 설명하도록 한다.Further, preferably, the electrode lead has a recess formed inwardly concave, and the welding spot may be configured to be positioned at least partially in the recess. This will be described in more detail with reference to FIG.
도 10은, 본 발명의 다른 실시예에 따른 전극 리드와 버스바의 용접 구성을 개략적으로 나타내는 단면도이다. 다만, 도 10에서도, 설명의 편의를 위해, 전극 리드의 일부와 버스바만 도시되도록 한다.10 is a cross-sectional view schematically showing a welding configuration of an electrode lead and a bus bar according to another embodiment of the present invention. However, in Fig. 10, for convenience of explanation, only a part of the electrode lead and the bus bar are shown.
도 10을 참조하면, 2개의 전극 리드(111)가 1개의 버스바(200)를 중심으로 양측에서 접근하여 버스바(200)의 전면(도 10의 상부면)에 적층되어 용접될 수 있다. 이러한 구성에서, 2개의 전극 리드(111)는, 도 10에서 G1으로 표시된 바와 같이, 내측 방향(도 10의 +X축 방향)으로 오목하게 형성된 형태의 오목부를 각각 구비할 수 있다. 여기서, 내측 방향이란, 배터리 모듈 내지 이차 전지의 중심부를 향하는 방향으로서, 전극 리드가 이차 전지 본체에서 돌출되는 방향의 반대 방향이라 할 수 있다. 예를 들어, 도 10을 기준으로, 각 전극 리드(111)는, 상부 방향(도면의 -X축 방향)으로 연장되다가 수평 방향(Y축 방향)으로 절곡된 상태에서 다시 하부 방향으로 절곡된 후, 수평 방향으로 절곡되어 오목부를 형성하고, 단부가 다시 상부 방향으로 절곡되는 형태로 구성될 수 있다.10, two electrode leads 111 may be laminated and welded on the front surface (upper surface in FIG. 10) of the bus bar 200 by approaching from both sides with respect to one bus bar 200. In this configuration, the two electrode leads 111 may each have a concave portion formed in a recessed shape in the inner direction (+ X-axis direction in Fig. 10) as indicated by G1 in Fig. Here, the inward direction refers to a direction toward the center of the battery module or the secondary battery, and may be a direction opposite to a direction in which the electrode leads protrude from the secondary battery body. For example, with reference to Fig. 10, each electrode lead 111 extends upward (in the -X-axis direction in the drawing) and then bent in the horizontal direction (Y-axis direction) , It may be configured such that it is bent in the horizontal direction to form a concave portion and the end portion is bent upward again.
이 경우, 용접 스팟(W)의 전체 또는 일부는 이러한 전극 리드의 벤딩에 의해 형성된 오목부(G1)에 위치할 수 있다. 즉, 도 10에 도시된 바와 같이, 용접 스팟(W)은, 2개의 전극 리드(111)에서 오목하게 형성된 부분에 위치할 수 있다.In this case, all or a part of the welding spot W may be located in the concave portion G1 formed by the bending of the electrode lead. That is, as shown in FIG. 10, the welding spot W may be located at a portion formed concavely in the two electrode leads 111.
본 발명의 이러한 구성에 의하면, 전극 리드(111) 사이의 결합력이 보다 향상될 수 있다. 즉, 2개의 전극 리드(111)는 용접 스팟(W)에 의해 상호 고정됨은 물론이고, 오목부(G1) 간 결합으로 기계적 결합 강도가 보다 향상될 수 있다. 즉, 상대적으로 전방(도 10의 상부)에 위치한 전극 리드에 오목부가 형성되면, 해당 전극 리드의 후면 측에서는 볼록부가 형성되어 있다고도 할 수 있다. 그리고, 이러한 볼록부는 그보다 후방에 위치한 전극 리드의 오목부에 삽입될 수 있다. 따라서, 이러한 전극 리드 간 삽입 결합에 의해, 전극 리드 간 결합력은 더욱 향상될 수 있다. According to this configuration of the present invention, the bonding force between the electrode leads 111 can be further improved. That is, not only the two electrode leads 111 are fixed to each other by the welding spot W, but also the mechanical coupling strength can be further improved by the coupling between the recesses G1. That is, when the concave portion is formed in the electrode lead located relatively forward (the upper portion in Fig. 10), a convex portion may be formed on the rear side of the electrode lead. The convex portion can be inserted into the concave portion of the electrode lead located further behind. Therefore, by this insertion between the electrode leads, the bonding force between the electrode leads can be further improved.
또한, 이러한 오목부(G1)에 의해 용접 스팟(W)에 가해지는 인장력을 줄일 수 있다. 예를 들어, 도 10의 구성에서, 힘이 좌우 방향(도면의 Y축 방향)으로 가해지는 경우, 전극 리드에 형성된 오목부(G1)가, 전극 리드에 가해지는 좌우 방향 힘을 완충할 수 있다. 따라서, 오목부(G1)에 형성된 용접 스팟(W)으로 이러한 힘이 그대로 전달되지 않고 감소되어 전달되도록 할 수 있다. In addition, the tensile force applied to the weld spot W can be reduced by the concave portion G1. For example, in the configuration of Fig. 10, when the force is applied in the lateral direction (Y-axis direction in the drawing), the concave portion G1 formed in the electrode lead can buffer the lateral force applied to the electrode lead . Therefore, such a force can be reduced and transmitted to the welding spot W formed in the concave portion G1 without being transmitted.
뿐만 아니라, 이러한 오목부(G1)에 의해 전극 리드 간 결합 위치나 용접 스팟의 위치가 용이하게 파악 및 가이드될 수 있으므로, 전극 리드 간 결합 및 용접 공정이 보다 원활하게 이루어질 수 있다.In addition, since the positions of the electrode leads and the positions of the welding spots can be easily grasped and guided by the concave portion G1, the bonding between the electrode leads and the welding process can be performed more smoothly.
한편, 상기 여러 실시예에서는, 나선 형태로 구성된 2개의 용접 라인에 의해 하나의 토네이도, 즉 하나의 용접 스팟이 구성되는 형태를 중심으로 설명되었으나, 3개 이상의 용접 라인이 하나의 토네이도를 구성하는 형태로 용접 스팟이 구성될 수 있다.Meanwhile, in the above-described embodiments, the description has been made on the form in which one tornado, that is, one welding spot is formed by two welding lines formed in a helical form. However, in the case where three or more welding lines constitute one tornado A welding spot can be constructed.
도 11은, 본 발명의 다른 실시예에 따른 용접 스팟의 구성을 개략적으로 나타내는 도면이다.11 is a view schematically showing a configuration of a welding spot according to another embodiment of the present invention.
도 11을 참조하면, 하나의 토네이도, 즉 하나의 용접 스팟(W)에 3개의 용접 라인(w1, w2, w3)이 포함되며, 각각의 용접 라인은 외측 단부와 내측 단부가 각각 별도로 구비될 수 있다. 그리고, 3개의 용접 라인(w1, w2, w3)은, 외측 단부에서 내측 단부에 이르는 형태가 각각 나선 형태로 구성될 수 있다.11, one tornado, i.e., one weld spot W, includes three weld lines w1, w2, w3, each of which may have its outer end and its inner end separately provided have. The three welding lines w1, w2 and w3 may have a spiral shape from the outer end to the inner end, respectively.
또한, 상기 여러 실시예에서는, 토네이도를 구성하는 각 용접 라인이 외측 단부에서 내측 단부까지 나선 형태로 형성된 구성을 중심으로 설명되었으나, 본 발명이 반드시 이러한 실시예로 한정되는 것은 아니다.In the above embodiments, the welding lines constituting the tornado are formed in a spiral shape from the outer end to the inner end, but the present invention is not necessarily limited to these embodiments.
도 12는, 본 발명의 또 다른 실시예에 따른 용접 스팟의 구성을 개략적으로 나타내는 도면이다.12 is a view schematically showing the configuration of a welding spot according to another embodiment of the present invention.
도 12를 참조하면, 하나의 토네이도에 2개의 용접 라인(w1, w2)이 구비되는데, 이때, 각 용접 라인은 전체적으로 완전한 나선이 아닌 형태로 구성될 수 있다. 즉, 도 12에 도시된 바와 같이, 제1 용접 라인(W1)의 외측 단부 및 제2 용접 라인(W2)의 외측 단부는, e1 및 e2로 표시된 부분과 같이, 절곡된 형태로 구성될 수 있다. 더욱이, 이때, 제1 용접 라인(W1) 및 제2 용접 라인(W2)의 절곡된 말단부는, 직선 형태로 구성될 수 있다.Referring to FIG. 12, two welding lines w1 and w2 are provided in one tornado, wherein each welding line may be formed in a shape other than a complete spiral as a whole. Namely, as shown in Fig. 12, the outer end of the first welding line W1 and the outer end of the second welding line W2 can be formed in a bent form, such as a portion denoted by e1 and e2 . Further, at this time, the bent end portions of the first welding line W1 and the second welding line W2 may be formed in a straight line shape.
특히, 본 발명의 이러한 구성에 의하면, 토네이도를 구성하는 용접 라인의 패턴이 일정하지 않고 변화되기 때문에, 크랙의 성장에 대한 억제력이 증대될 수 있다. 또한, 이러한 용접 라인의 절곡 구성을 통해, 용접 라인의 말단부에 가해지는 피로도가 감소될 수 있다.Particularly, according to this configuration of the present invention, since the pattern of the weld line constituting the tornado is changed without being constant, the restraining force against crack growth can be increased. Further, through the bending configuration of such a welding line, the fatigue applied to the distal end of the welding line can be reduced.
도 13은, 본 발명의 다른 실시예에 따른 용접 스팟의 구성을 개략적으로 나타내는 도면이다. 13 is a view schematically showing a configuration of a welding spot according to another embodiment of the present invention.
도 13을 참조하면, 하나의 전극 리드 상에 다수의 용접 스팟(W)이 배열될 때, 토네이도 형태로 구성된 각 용접 스팟은, 용접 스팟의 배열 방향의 폭이 그에 직교하는 방향의 폭보다 짧게 구성될 수 있다. 여기서, 폭이란, 용접 스팟의 최외곽에 위치하는 용접 라인 사이의 거리라 할 수 있다. 특히, 용접 스팟의 폭은, 용접 스팟의 최외곽 용접 라인 사이의 직선 거리 중 최대 거리일 수 있다.13, when a plurality of welding spots W are arranged on one electrode lead, each welding spot formed in a tornado shape is configured such that the width in the direction of arrangement of the welding spots is shorter than the width in the direction orthogonal thereto . Here, the width may be the distance between welding lines located at the outermost part of the welding spot. In particular, the width of the weld spot may be the maximum distance of the straight line distance between the outermost weld lines of the weld spot.
예를 들어, 용접 스팟(W)이 상하 방향(도면의 Z축 방향)으로 둘 이상 배치되는 경우, 각 용접 스팟의 상하 방향 폭의 길이를 f1이라 하고, 각 용접 스팟의 좌우 방향(도면의 Y축 방향) 폭의 길이를 f2라 할 때, 각 용접 스팟의 토네이도는 f1보다 f2가 큰 형태로 구성될 수 있다. 이 경우, 각 용접 스팟은 대략 타원 형태로 구성되어 있다고 할 수 있다.For example, when two or more welding spots W are arranged in the vertical direction (the Z-axis direction in the figure), the vertical length of each welding spot is denoted by f1, and the horizontal direction of each welding spot Axial direction) width is f2, the tornado of each welding spot can be configured in such a manner that f2 is larger than f1. In this case, it can be said that each welding spot is formed in an approximately elliptic shape.
본 발명의 이러한 구성에 의하면, 폭(도면에서 전극 리드의 Z축 방향 길이)이 짧게 구성된 전극 리드의 경우에도, 가급적 많은 수의 용접 스팟(W)이 포함되도록 하거나, 각 용접 스팟(W) 간 거리를 늘릴 수 있다. 또한, 전극 리드의 접촉 면적에 대하여 가급적 넓은 용접 면적을 확보할 수 있다. 그러므로, 본 발명의 이러한 구성에 의하면, 용접에 대한 공정성 및 용접 강도가 더욱 개선될 수 있다.According to this configuration of the present invention, even in the case of an electrode lead having a short width (length in the Z-axis direction of the electrode lead in the drawing), it is possible to include as many welding spots W as possible, You can increase the distance. Further, it is possible to secure a wider welding area as far as possible against the contact area of the electrode leads. Therefore, according to this configuration of the present invention, the fairness and welding strength for welding can be further improved.
본 발명에 따른 배터리 모듈은, 셀 어셈블리(100) 및 버스바 이외에, 모듈 케이스 등을 더 포함할 수 있다. 여기서, 모듈 케이스는, 내부에 빈 공간이 형성되어, 이러한 빈 공간에 셀 어셈블리(100)와 버스바 등의 여러 구성요소를 수납하도록 구성될 수 있다. 이 밖에도, 본 발명에 따른 배터리 모듈은, 본 발명의 출원 시점에 공지된 배터리 모듈의 여러 구성요소를 더 포함할 수 있다.The battery module according to the present invention may further include a module case and the like in addition to the cell assembly 100 and the bus bar. Here, the module case may have an empty space formed therein, and may be configured to accommodate various components such as the cell assembly 100 and the bus bar in the empty space. In addition, the battery module according to the present invention may further include various components of the battery module known at the time of filing of the present invention.
본 발명에 따른 배터리 팩은, 본 발명에 따른 배터리 모듈을 하나 이상 포함할 수 있다. 또한, 본 발명에 따른 배터리 팩은, 이러한 배터리 모듈 이외에, 배터리 모듈을 수납하기 위한 팩 케이스, 배터리 모듈의 충방전을 제어하기 위한 각종 장치, 이를테면 BMS(Battery Management System), 전류 센서, 퓨즈 등이 더 포함될 수 있다.The battery pack according to the present invention may include at least one battery module according to the present invention. In addition to the battery module, the battery pack according to the present invention may include a pack case for storing the battery module, various devices for controlling charge and discharge of the battery module, such as a BMS (Battery Management System), a current sensor, . ≪ / RTI >
본 발명에 따른 배터리 모듈은, 전기 자동차나 하이브리드 자동차와 같은 자동차에 적용될 수 있다. 즉, 본 발명에 따른 자동차는, 본 발명에 따른 배터리 모듈을 포함할 수 있다. 특히, 본 발명에 따른 배터리 모듈의 경우, 충격이나 진동에도 전극 리드(111) 및/또는 버스바의 용접에 의한 전기적 연결 상태가 안정적으로 유지될 수 있다. 따라서, 이러한 배터리 모듈이 적용된 자동차의 경우, 안전성이 크게 향상될 수 있다.The battery module according to the present invention can be applied to an automobile such as an electric car or a hybrid car. That is, the automobile according to the present invention may include a battery module according to the present invention. Particularly, in the case of the battery module according to the present invention, the electrical connection state by the welding of the electrode lead 111 and / or the bus bar can be stably maintained even in case of impact or vibration. Therefore, in the case of a vehicle to which such a battery module is applied, the safety can be greatly improved.
이하, 본 발명을 보다 구체적으로 설명하기 위해 실시예 및 비교예를 들어 보다 상세하게 설명하기로 한다. 다만, 본 발명에 따른 실시예는 여러 가지 다른 형태로 변형될 수 있으며, 본 발명의 범위가 아래에서 상술하는 실시예에 한정되는 것으로 해석되어서는 안 된다. 본 발명의 실시예는 당업계에서 평균적인 지식을 가진 자에게 본 발명을 보다 완전하게 설명하기 위해서 제공되는 것이다.Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. It should be understood, however, that the embodiments of the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. The embodiments of the present invention are provided to enable those skilled in the art to more fully understand the present invention.
(실시예 1 내지 3)(Examples 1 to 3)
도 14에 도시된 바와 같이, 2개의 전극 리드(111), 즉 1개의 양극 리드, 1개의 음극 리드 및 1개의 버스바(200)와 함께 전후 방향으로 상호 적층시킨 상태에서, 미야찌코리아 사의 레이저 용접 장비(FK-F6000-MM-CT)를 이용하여 토네이도 형태의 용접 스팟(W)을 6개 형성함으로써, 2개의 전극 리드와 버스바가 서로 용접된 실시예 샘플을 3개 준비하였다.As shown in Fig. 14, in a state in which two electrode leads 111, that is, one positive electrode lead, one negative electrode lead, and one bus bar 200 are laminated in the front-back direction, Six sample spots (W) in the form of a tornado were formed using a welding machine (FK-F6000-MM-CT) to prepare three sample samples in which two electrode leads and a bus bar were welded to each other.
이때, 모든 실시예 샘플의 양극 리드는 알루미늄 재질로 구성되어 0.2mm의 두께를 갖고, 음극 리드는 구리 재질로 구성되어 0.2mm의 두께를 가지며, 버스바는 구리 재질로 구성되어 0.6mm의 두께를 갖도록 하였다.At this time, the positive electrode leads of all the samples of the embodiment are made of aluminum and have a thickness of 0.2 mm, the negative electrode lead is made of copper and has a thickness of 0.2 mm and the bus bar is made of copper and has a thickness of 0.6 mm Respectively.
그리고, 각 용접 스팟은, 도 8에 도시된 바와 같은 토네이도 형태로 구성되도록 하였다. 이때, 토네이도의 외경(가장 긴 폭의 길이)은 약 3mm, 토네이도의 개수는 6개, 토네이도 간 간격은 3.4mm, 용접 라인 간 간격은 0.004mm가 되도록 하였다.Then, each welding spot was configured in the form of a tornado as shown in Fig. At this time, the outer diameter (longest width) of the tornado was about 3 mm, the number of tornadoes was 6, the distance between the tornados was 3.4 mm, and the distance between the welding lines was 0.004 mm.
또한, 레이저 용접 시, 레이저 출력은 1.5kW이고, 속도는 100 mm/s가 되도록 하였다.In laser welding, the laser output was 1.5 kW and the speed was 100 mm / s.
(비교예 1 내지 3)(Comparative Examples 1 to 3)
상기 실시예 1 내지 3과 동일한 재질 및 형태를 갖는 전극 리드 및 버스바를 이용하여, 실시예 1 내지 3과 동일한 형태로 상호 적층되도록 하였다. 그리고, 이러한 2개의 전극 리드와 버스바 사이가 용접되도록 하였는데, 이때 용접 형태는, 도 1에 도시된 바와 같은 형태로 구성되도록 함으로써, 비교예 1 내지 3 샘플을 준비하였다. Using electrode leads and bus bars having the same material and shape as those of Examples 1 to 3, they were laminated in the same manner as in Examples 1 to 3. Then, the two electrode leads and the bus bar were welded together. At this time, the welding configurations were made as shown in FIG. 1, so that the samples of Comparative Examples 1 to 3 were prepared.
즉, 비교예 1 내지 3의 샘플에서는, 2개의 용접 라인이 전극 리드의 폭 방향으로 길게 형성된 형태로, 2개의 전극 리드와 버스바가 용접되도록 하였다.That is, in the samples of Comparative Examples 1 to 3, two electrode leads and a bus bar were welded in such a manner that two welding lines were elongated in the width direction of the electrode leads.
이때, 각 용접 라인의 전체 길이는 35mm, 용접 라인 간 간격은 1.2mm가 되도록 하였다.At this time, the total length of each welding line was set to 35 mm, and the interval between the welding lines was set to 1.2 mm.
이러한 비교예 1 내지 3의 샘플에서도, 2개의 전극 리드와 버스바 사이의 용접을 위해 상기 실시예에서와 동일한 미야찌코리아 사의 레이저 용접 장비를 이용하였다. 그리고, 레이저 용접 시 레이저 출력은 1.5kW이고, 속도는 95 mm/s가 되도록 하였다. 또한, 비교예 1 내지 3의 샘플에서 레이저 용접 라인의 길이는, 대략 실시예 1 내지 3의 샘플에서의 레이저 용접 부분의 전체 길이와 대략 유사하도록 하였다.Also in the samples of Comparative Examples 1 to 3, the laser welding equipment of Miyachi Corporation was used for welding between the two electrode leads and the bus bar. In laser welding, the laser output was 1.5 kW and the speed was 95 mm / s. In addition, the lengths of the laser welding lines in the samples of Comparative Examples 1 to 3 were substantially similar to the total length of the laser welded portions in the samples of Examples 1 to 3.
상기 실시예 및 비교예 샘플 각각에 대하여, Nanotech사의 NA-TS250K 장비를 이용하여 인장 강도를 측정하였다. Tensile strength was measured using NA-TS250K equipment of Nanotech Co., Ltd. for each of the above Examples and Comparative Examples.
측정 방식은, 가장 상부에 적층된 전극 리드의 일부를 커팅 또는 벤딩시킨 후, 중앙에 적층된 전극 리드, 즉 버스바에 접촉하고 있는 전극 리드와 버스바를 서로 반대 방향으로 잡아당겼다. 예를 들어, 도 14의 구성을 참조하면, 중앙에 적층된 우측 전극 리드(111)는 우측 방향으로, 가장 하부에 위치한 버스바(200)는 좌측 방향으로 잡아당겼다. 그리고, 이러한 인장력에 의해 용접부가 파손되는 강도를 측정하였으며, 그 측정 결과는, 도 15에 실시예 1 내지 3 및 비교예 1 내지 3으로서 도시하였다.In the measurement method, after cutting or bending a part of the electrode leads laminated on the uppermost portion, the electrode leads and the bus bars in contact with the electrode leads stacked in the center, that is, the bus bars, were pulled in directions opposite to each other. For example, referring to the configuration of Fig. 14, the right electrode lead 111 stacked at the center pulls in the right direction, and the bus bar 200 at the lowermost position pulls in the left direction. Then, the strength at which the welded portion was broken by the tensile force was measured. The measurement results are shown in Fig. 15 as Examples 1 to 3 and Comparative Examples 1 to 3.
도 15를 참조하면, 실시예 1 내지 3의 샘플의 경우, 인장 강도가 46.484 kgf 내지 48.935 kgf으로서, 인장 강도의 평균이 47.530 kgf으로 측정되었다. 여기서, 모재 강도는 57.270 kgf인데, 이 경우 상기 인장 강도 측정값은 이러한 모재 강도의 약 82.99%에 해당하는 값이다. 반면, 비교예 1 내지 3의 샘플의 경우, 인장 강도가 37.756 kgf 내지 41.972 kgf으로서, 인장 강도의 평균이 40.371 kgf으로 측정되었다. 그리고, 이는 모재 강도가 57.270 kgf일 때, 모재 강도 대비 약 70.49%에 해당하는 값이다.Referring to Fig. 15, in the case of the samples of Examples 1 to 3, the tensile strength was 46.484 kgf to 48.935 kgf, and the average tensile strength was 47.530 kgf. Here, the base material strength is 57.270 kgf, where the tensile strength measurement value corresponds to about 82.99% of the base material strength. On the other hand, in the case of the samples of Comparative Examples 1 to 3, the tensile strength was 37.756 kgf to 41.972 kgf, and the average tensile strength was 40.371 kgf. When the base material strength is 57.270 kgf, it is about 70.49% of the base material strength.
이러한, 측정 결과를 보면 알 수 있듯이, 본 발명과 같이 토네이도 형태로 형성된 다수의 용접 스팟을 이용하여 하나 이상의 전극 리드와 버스바를 용접하는 경우, 종래의 직선 형태의 용접 구성에 비해, 인장 강도가 크게 향상되는 것을 알 수 있다. 더욱이, 상기 실시예 샘플에서의 레이저 용접 속도는, 비교예 샘플에서의 레이저 용접 속도보다 빠르게 하였음에도, 실시예 샘플은, 비교예 샘플보다 우수한 인장 강도를 나타내었다.As can be seen from the measurement results, when one or more electrode leads and a bus bar are welded by using a plurality of welding spots formed in the form of a tornado as in the present invention, compared to a conventional linear welding configuration, . Furthermore, although the laser welding speed in the sample of the above example was faster than the laser welding speed in the comparative sample, the sample of the example exhibited a tensile strength better than that of the sample of the comparative example.
(실시예 4 내지 6)(Examples 4 to 6)
상기 실시예 1 내지 3의 샘플과 전체적인 구성, 특히 용접 구성이 대략 동일하되 전극 리드와 버스바의 재질 및/또는 두께만을 달리하여, 실시예 4 내지 6 샘플을 준비하였다. Samples of Examples 4 to 6 were prepared by varying only the material and / or thickness of the electrode lead and the bus bar with respect to the overall configuration of the samples of Examples 1 to 3, particularly the welding configuration.
즉, 실시예 4 내지 6에서는, 양극 리드와 음극 리드는 모두 알루미늄 재질로 구성되며 0.4mm의 두께를 갖도록 하였다. 그리고, 버스바는, 구리 재질로 구성되며 3.0mm의 두께를 갖도록 하였다.That is, in Examples 4 to 6, both the positive electrode lead and the negative electrode lead were made of aluminum and had a thickness of 0.4 mm. The bus bar is made of copper and has a thickness of 3.0 mm.
(실시예 7 내지 9)(Examples 7 to 9)
상기 실시예 4 내지 6의 샘플과 전극 리드 및 버스바의 구성은 대략 동일하되, 용접 구성만을 달리하여 실시예 7 내지 9 샘플을 제조하였다.The samples of Examples 4 to 6 and the electrode leads and the bus bar were substantially the same, but the samples of Examples 7 to 9 were produced with different welding configurations only.
즉, 2개의 전극 리드와 버스바를 적층하여 6개의 용접 스팟을 형성하되, 각 용접 스팟은, 도 16에 도시된 바와 같이, 나선 형태의 용접 라인을 1개만 갖는 토네이도 형태로 구성되도록 하였다.That is, the two electrode leads and the bus bar are laminated to form six welding spots, and each welding spot is configured in a tornado shape having only one spiral welding line as shown in FIG.
이때, 각 용접 스팟의 직경, 개수, 용접 스팟 간 간격, 용접 라인 간 간격은 실시예 4 내지 6, 다시 말해 실시예 1 내지 3과 유사한 형태로 구성하였다.At this time, the diameter, the number of weld spots, the interval between weld spots, and the interval between weld lines were configured in the same manner as in Examples 4 to 6, that is, in Examples 1 to 3.
상기 실시예 4-9 샘플 각각에 대하여, 상기 실시예 1 내지 3에서와 동일한 장비 및 방식으로 인장 강도를 측정하였다. 그리고, 그 측정 결과는, 도 17에 실시예 4 내지 9로서 도시하였다.For each of the samples of Examples 4-9, the tensile strength was measured by the same equipment and manner as in Examples 1 to 3 above. The measurement results are shown in Figs. 17 to 17 as Examples 4 to 9.
도 17을 참조하면, 실시예 4 내지 6의 경우, 모든 샘플의 인장 강도가 대략 134 kgf 내지 137 kgf으로서, 3개의 샘플 모두 유사한 인장 강도 특성을 나타내었다.Referring to Fig. 17, in the case of Examples 4 to 6, the tensile strength of all the samples was approximately 134 kgf to 137 kgf, and all three samples exhibited similar tensile strength characteristics.
반면, 실시예 7 내지 9의 경우, 3개의 샘플 중 1개의 샘플, 즉 실시예 8의 샘플에서는 인장 강도 측정값이 130 kgf 미만으로 떨어지는 결과를 나타내었다. On the other hand, in the case of Examples 7 to 9, one sample out of three samples, that is, the sample of Example 8, showed a tensile strength measurement value lower than 130 kgf.
이러한 측정 결과를 보면, 토네이도 형태에 있어서, 하나의 나선을 구비하는 토네이도 형태로 용접 스팟을 구성하기보다는, 다수의 나선, 특히 2개의 나선을 구비하는 토네이도 형태로 용접 스팟을 구성하는 경우, 용접 강도가 더욱 향상되며, 용접성이 안정적으로 확보됨을 알 수 있다.The results of this measurement show that, in the case of a tornado shape, if a welding spot is formed in the form of a tornado having a plurality of spirals, especially two spirals, rather than a welding spot in the form of a tornado having one spiral, And the weldability can be stably secured.
이처럼 2개의 용접 라인을 갖는 토네이도 용접 형태와 1개의 용접 라인을 갖는 토네이도 용접 형태의 추가 특성 비교를 위해, 다음과 같은 실험을 더 진행하였다.In order to compare the characteristics of the tornado welding type with two welding lines and the tornado welding type with one welding line, the following experiment was further conducted.
(실시예 10)(Example 10)
상기 실시예 4 내지 6의 샘플과 동일한 형태 및 용접 구성을 갖는 형태로 실시예 10 샘플을 준비하였다.Samples of Example 10 were prepared in the same form and the weld configuration as the samples of Examples 4 to 6 above.
(실시예 11)(Example 11)
상기 실시예 7 내지 9의 샘플과 동일한 형태 및 용접 구성을 갖는 형태로 실시예 11 샘플을 준비하였다.Samples of Example 11 were prepared in the same form and the weld configuration as the samples of Examples 7 to 9 above.
상기 실시예 10 및 11 샘플 각각에 대하여, NA-TS250K 장비를 이용하여, 인장 강도를 측정하는 방식으로 인장 강도를 측정하면서, 그에 따른 박리 여부를 관측하였다. 그리고, 그러한 박리 여부 관측 결과에 대한 사진을 도 18 및 도 19에 나타내었다. With respect to each of the samples of Examples 10 and 11, the tensile strength was measured using a NA-TS250K instrument in such a manner that the tensile strength was measured, and the peeling was observed. Figs. 18 and 19 show photographs of the observation results of such peeling.
즉, 도 18은 실시예 10에 대한 인장 강도 측정 방식으로 실험을 진행하면서 박리 여부를 촬영한 이미지이고, 도 19는 실시예 11에 대한 인장 강도 측정 방식으로 실험을 진행하면서 박리 여부를 촬영한 이미지이다.FIG. 18 is an image of the tensile strength measurement method according to Example 10 taken while the experiment is conducted, FIG. 19 is an image showing the tensile strength measurement method according to Example 11, to be.
먼저, 도 18을 참조하면, 인장 강도 테스트를 진행한 결과, 실시예 10의 모든 용접 스팟에 걸쳐 모재 자체가 파단될 뿐, 용접 부분이 박리되는 결과는 관찰되지 않았다. Referring to FIG. 18, as a result of the tensile strength test, only the base material itself was broken over all the weld spots of Example 10, and no result of peeling of the weld portion was observed.
반면, 도 19를 참조하면, 인장 강도 테스트를 진행한 결과, 실시예 11의 다수 용접 스팟 중 일부(2개) 용접 스팟 부분에서 용접 부분이 박리되는 결과가 관찰되었다. 즉, 도 19에서 H로 표시된 부분과 같이, 실시예 11에 의한 용접 구성에서는, 일부 용접 스팟 부분에서 모재가 파손되지 않고 용접 부분이 박리되는 결과가 확인되었다.On the other hand, referring to FIG. 19, as a result of carrying out the tensile strength test, it was observed that some (two) of the plurality of welding spots of Example 11 were peeled off at the welding spot portion. That is, as in the portion indicated by H in Fig. 19, in the welding configuration according to Example 11, it was confirmed that the base material was not broken at some welding spots and the welding portion was peeled off.
상기와 같은 테스트 결과에 의하면, 각 용접 스팟이 나선 형태의 다수의 용접 라인, 즉 2개의 나선형 용접 라인을 구비하는 경우, 1개의 나선형 용접 라인을 구비하는 경우에 비해, 용접 부분이 쉽게 박리되지 않고, 보다 강한 강도로 용접이 더 잘 이루어질 수 있다는 것을 알 수 있다. 따라서, 2개 이상의 나선형 용접 라인을 구비하여 토네이도가 형성된 용접 스팟의 경우, 용접에 대한 신뢰성이 보다 향상됨을 알 수 있다.According to the test results as described above, when each welding spot has a plurality of helical welding lines, that is, two helical welding lines, the welding portion is not easily peeled off , It can be seen that the welding can be done with a stronger strength. Thus, it can be seen that, in the case of a weld spot having two or more helical welding lines and formed with a tornado, the reliability of welding is further improved.
한편, 배터리 모듈의 양산 과정에서 하나 이상의 전극 리드와 버스바를 서로 겹쳐서 용접을 수행하는 경우, 전극 리드와 버스바 사이에 어느 정도 간격(Gap)이 생길 수 있는데, 이러한 간격이 양산성에 큰 영향을 미칠 수 있다. 따라서, 이러한 Gap 발생에 따른 용접 불량과 관련하여, 본원발명의 효과를 살펴보기 위해 다음과 같은 실험을 실시하였다.Meanwhile, when welding is performed by overlapping one or more electrode leads and the bus bar in the process of mass production of the battery module, a gap may be formed between the electrode leads and the bus bar to some degree, . Therefore, in order to investigate the effect of the present invention, the following experiment was carried out in connection with the weld defect due to the occurrence of the gap.
(실시예 12 내지 26)(Examples 12 to 26)
상기 실시예 1 내지 3의 샘플과 전체적인 구성, 특히 용접 구성이 대략 동일하도록 구성하되 전극 리드와 버스바의 재질 및/또는 두께를 달리하여, 실시예 12 내지 26 샘플을 준비하였다.Samples of Examples 12 to 26 were prepared in such a manner that the overall configuration, particularly the welding configuration, of the samples of Examples 1 to 3 was substantially the same, but the materials and / or thicknesses of the electrode leads and bus bars were different.
즉, 실시예 12 내지 26에서는, 양극 리드의 경우 알루미늄 재질로서 0.4mm의 두께를 갖도록 하였고, 음극 리드의 경우 구리 재질로서 0.2mm의 두께를 갖도록 하였다. 또한, 버스바는 구리 재질로서 3mm의 두께를 갖도록 하였다.That is, in Examples 12 to 26, the cathode lead was made of aluminum material to have a thickness of 0.4 mm, and the cathode lead was made of copper material to have a thickness of 0.2 mm. The bus bar was made of copper and had a thickness of 3 mm.
그리고, 도 8에 도시된 바와 같은 토네이도 형태로 구성되도록 하였으며, 토네이도의 외경은 약 3mm, 토네이도의 개수는 6개, 토네이도 간 간격은 3.4mm, 용접 라인 간 간격은 0.004mm가 되도록 하였다. 또한, 레이저 용접 시, 레이저 출력은 1.5kW이고, 속도는 100 mm/s가 되도록 하였다. 이때, 레이저 용접 장비는, 앞선 실시예들과 마찬가지로 미야찌코리아 사의 FK-F6000-MM-CT를 이용하였다.8, the outer diameter of the tornado was about 3 mm, the number of tornadoes was 6, the distance between the tornadoes was 3.4 mm, and the distance between the welding lines was 0.004 mm. In laser welding, the laser output was 1.5 kW and the speed was 100 mm / s. At this time, the laser welding equipment used was FK-F6000-MM-CT of Miyachi Corporation as in the previous embodiments.
특히, 실시예 12 내지 26의 경우, 전극 리드와 버스바 사이의 간격(Gap)이 서로 달라지도록 구성하였다. 즉, 실시예 12 내지 26의 15개 샘플에 대하여, 버스바와 직접 접촉된 중앙에 적층된 전극 리드와 그 하부에 위치한 버스바 사이의 간격(Gap)을 0.04mm 내지 0.6mm의 범위 내에서 서로 달리 한 상태에서, 전극 리드와 버스바 사이가 용접되도록 하였다. 이때, 전극 리드와 버스바 사이의 간격은 이격된 공간의 소정 부분에 중간재를 개재시킴으로써 거리가 유지되도록 하였다. 실시예 12 내지 26의 각 실시예 샘플에서의 리드와 버스바 사이의 간격은, 도 20의 표에 나타낸 바와 같다.Particularly, in the case of Examples 12 to 26, the gap between the electrode leads and the bus bar is different from each other. That is, for the 15 samples of Examples 12 to 26, the gap between the electrode leads stacked in the center directly in contact with the bus bar and the bus bars located thereunder was varied within a range of 0.04 mm to 0.6 mm In this state, the electrode lead and the bus bar were welded together. At this time, the distance between the electrode lead and the bus bar was maintained by interposing an intermediate member in a predetermined portion of the spaced space. The intervals between the leads and the bus bars in each of the examples of Examples 12 to 26 are as shown in the table of Fig.
(비교예 4 내지 18)(Comparative Examples 4 to 18)
상기 실시예 12 내지 26과 동일한 재질 및 형태를 갖는 전극 리드 및 버스바를 이용하여, 실시예 12 내지 26과 동일한 형태로 상호 적층되도록 하였다. 그리고, 이러한 2개의 전극 리드와 버스바 사이가 용접되도록 하였는데, 이때 용접 구성은, 비교예 1 내지 3과 같은 형태가 되도록 하였다. 즉, 비교예 4 내지 18의 경우, 도 1에 도시된 바와 같이 2개의 직선 형태의 용접 라인을 통해 2개의 전극 리드 및 버스바가 용접되도록 하였다. 그리고, 용접 라인의 전체 길이는 35mm, 용접 라인 간 간격은 1.2mm가 되도록 하였으며, 레이저 출력은 1.5kW이고, 속도는 95 mm/s가 되도록 하였다. 이 경우에도, 레이저 용접 장비는, 앞선 비교예들과 마찬가지로 미야찌코리아 사의 FK-F6000-MM-CT를 이용하였다The electrode leads and the bus bars having the same material and shape as those of Examples 12 to 26 were stacked in the same manner as in Examples 12 to 26. Then, the two electrode leads and the bus bar were welded together. At this time, the welding configuration was the same as that of Comparative Examples 1 to 3. That is, in the case of Comparative Examples 4 to 18, two electrode leads and a bus bar were welded through two straight line welding lines as shown in FIG. The total length of the welding line was 35 mm and the distance between the welding lines was 1.2 mm. The laser output was 1.5 kW and the speed was 95 mm / s. In this case as well, the laser welding equipment used FK-F6000-MM-CT of Miyagi Korea Co., Ltd. as in the comparative examples
특히, 비교예 4 내지 18의 경우에도, 실시예 12 내지 26과 마찬가지로, 전극 리드와 버스바 사이의 간격(Gap)이 서로 순차적으로 달라지도록 구성하였다. 즉, 비교예 4 내지 18의 경우에도, 도 20에 기재된 바와 같이, 각 리드와 버스바 사이의 간격이 실시예 12 내지 26의 샘플과 동일하도록 구성하였다. 그리고, 이와 같이 간격이 서로 다르게 구성된 각 비교예 샘플에 대하여 직선 형태의 용접이 이루어지도록 하였다.Particularly, in the case of Comparative Examples 4 to 18, similarly to Examples 12 to 26, the gap (gap) between the electrode lead and the bus bar is sequentially changed from each other. That is, also in the case of Comparative Examples 4 to 18, as shown in Fig. 20, the gap between each lead and the bus bar was made to be the same as the samples of Examples 12 to 26. In this way, linear samples were welded to each of the comparative samples having different intervals.
먼저, 상기 실시예 12 내지 26 및 비교예 4 내지 18에 대하여, 육안으로 외관 상 탄흔, 기공, 비드 이상, 크랙 등의 결함(Visual Defect)이 발생하였는지를 관찰하고 그 결과를 도 21에 나타내었다. 이때, 별다른 결함이 관측되지 않은 경우, 도 21에 '×'로서 표시하였다. 반대로, 결함이 발생한 샘플에 대해서는, 도 21에 '○'로서 표시하였다.First, it was observed whether visual defects such as scratches, pores, bead abnormality, cracks or the like occurred visually in Examples 12 to 26 and Comparative Examples 4 to 18, and the results are shown in Fig. At this time, if no other defect is observed, it is indicated as 'x' in FIG. Conversely, a sample in which a defect has occurred is shown as "O" in FIG.
도 21의 결과를 참조하면, 먼저, 실시예의 경우, 실시예 12 내지 실시예 19까지는, 육안 관찰에 의해 별다른 결함이 관측되지 않았다. 즉, 본원발명의 실시예에 따르면, 전극 리드와 버스바 사이의 간격이 0.04mm 내지 0.32mm의 범위 내에서는, 큰 결함이 발생하지 않았다. 그리고, 실시예의 경우, 전극 리드와 버스바 사이의 간격이 0.36mm 이상이 된 샘플에서야 비로소 육안에 의해 결함이 관측되었다.Referring to the results of FIG. 21, first, in Examples 12 to 19, no significant defects were observed by visual observation. That is, according to the embodiment of the present invention, large defects do not occur within the range of 0.04 mm to 0.32 mm between the electrode lead and the bus bar. In the case of the embodiment, defects were observed only by the naked eye in the sample in which the distance between the electrode lead and the bus bar became 0.36 mm or more.
반면, 비교예의 경우, 비교예 4 내지 6까지는, 육안 관찰에 의해 별다른 결함이 관측되지 않았다. 그러나, 비교예 샘플의 경우, 비교예 7부터 비교예 18에 이르기까지 육안에 의해 결함이 관측되었다. 즉, 비교예의 경우, 리드와 버스바 사이의 간격이 0.16mm 이상만 되더라도 육안에 의해 결함이 관측될 수 있었다.On the other hand, in the case of the comparative example, no significant defect was observed by visual observation up to the comparative examples 4 to 6. However, in the case of the comparative sample, defects were visually observed from the comparative example 7 to the comparative example 18. That is, in the case of the comparative example, even if the distance between the lead and the bus bar was 0.16 mm or more, the defect could be observed by the naked eye.
이러한 실험 결과에 의하면, 본원발명에 의할 경우, 전극 리드와 버스바 사이의 간격이 어느 정도 존재하더라도, 비교예에 비해 결함이 쉽게 생성되지 않는다는 것을 알 수 있다. 그러므로, 본원발명에 의하면, 배터리 모듈의 양산 라인에서 전극 리드와 버스바 사이에 다소 Gap이 발생하더라도, 불량률이 현저하게 저하될 수 있으며, 이로 인해 양산성이 크게 향상될 수 있음을 알 수 있다.According to the experimental results, it can be seen that according to the present invention, even if there is a certain distance between the electrode lead and the bus bar, defects are not easily generated as compared with the comparative example. Therefore, according to the present invention, even if a slight gap is generated between the electrode lead and the bus bar in the mass production line of the battery module, the defective rate can be remarkably lowered, and the mass productivity can be greatly improved.
다음으로, 상기 실시예 12 내지 26 및 비교예 4 내지 18의 각 샘플에 대하여, NA-TS250K 장비를 이용하여 인장 강도를 측정하였으며, 그 결과를 도 22에 나타내었다.Next, for each of the samples of Examples 12 to 26 and Comparative Examples 4 to 18, tensile strength was measured using NA-TS250K equipment, and the results are shown in FIG.
도 22의 결과를 참조하면, 실시예 12 내지 26의 경우, 15개의 모든 샘플에 대하여 인장 강도가 대략 175kgf 내지 210kgf의 범위 내로 측정되었다. 반면, 비교예 샘플의 경우, Gap(전극 리드와 버스바 사이의 간격)이 0.24mm 이하로 작게 설정된 비교예 4 내지 9에 대해서만, 인장 강도가 대략 175kgf 내지 210kgf의 범위 내로 측정되었을 뿐, Gap이 0.28mm인 비교예 10의 경우에는 인장 강도가 170kgf 미만으로 낮게 측정되었다. 더욱이, Gap이 0.32mm 이상인 비교예 11 내지 18의 샘플에 대해서는 인장 강도 시험 시 리드와 버스바 사이가 곧바로 분리되었다. 즉, 비교예 11 내지 18의 샘플에서는 용접이 제대로 이루어지지 않았다고 할 수 있다. 따라서, 이러한 비교예 샘플들에 대해서는 인장 강도 자체가 측정될 수 없었으며, 이로 인해 도 22에는 표시되지 않았다.Referring to the results of FIG. 22, in the case of Examples 12 to 26, the tensile strength was measured within a range of about 175 kgf to 210 kgf for all 15 samples. On the other hand, in the case of the comparative sample, the tensile strength was measured within the range of about 175 kgf to 210 kgf only for Comparative Examples 4 to 9 in which the gap (gap between the electrode lead and the bus bar) was set to be as small as 0.24 mm or less, In the case of Comparative Example 10 having 0.28 mm, the tensile strength was measured as low as less than 170 kgf. Furthermore, samples of Comparative Examples 11 to 18 having a Gap of 0.32 mm or more were immediately separated between the lead and the bus bar in the tensile strength test. That is, the samples of Comparative Examples 11 to 18 were not welded properly. Thus, for these comparative samples, the tensile strength itself could not be measured, and as such is not shown in FIG.
이러한 측정 결과에 의하면, 본원발명의 실시예와 같이 토네이도 패턴에 의해 전극 리드와 버스바가 서로 용접되는 경우, 전극 리드와 버스바 사이에 어느 정도 간격이 벌어지더라도, 용접성이 안정적으로 확보된다는 것을 알 수 있다. 특히, 비교예의 측정 결과를 참조하면, 전극 리드와 버스바 사이가 0.32mm만 벌어지더라도 전극 리드와 버스바가 제대로 용접되지 못하는 반면, 본원발명의 실시예에 의할 경우, 전극 리드와 버스바 사이가 0.6mm로 벌어진 상태에서도 용접성이 안정적으로 유지될 수 있다. 더욱이, 비교예의 경우, 전극 리드와 버스바 사이의 간격이 0.28mm가 된 비교예 10의 경우, 인장 강도가 저하되기 시작하는 반면, 본원발명에 따른 실시예의 경우, 전극 리드와 버스바 사이의 간격이 계속해서 증가하더라도 인장 강도가 저하되는 패턴은 보이지 않고 있다.According to these measurement results, it was found that when the electrode lead and the bus bar are welded to each other by the tornado pattern as in the embodiment of the present invention, the weldability can be stably secured even if a gap is formed between the electrode lead and the bus bar to some extent . In particular, referring to the measurement results of the comparative example, the electrode lead and the bus bar can not be welded properly even if only 0.32 mm between the electrode lead and the bus bar is widened. On the other hand, according to the embodiment of the present invention, The weldability can be stably maintained even in the state where the gap is 0.6 mm. Further, in the case of the comparative example, in the case of the comparative example 10 in which the interval between the electrode leads and the bus bar was 0.28 mm, the tensile strength started to decrease. On the other hand, in the embodiment according to the present invention, A pattern in which the tensile strength is lowered is not seen even if the amount of the adhesive is continuously increased.
그러므로, 본원발명에 따른 배터리 모듈의 경우, 제조 과정에서 공정 상 한계나 오차, 불순물 등의 개입 등 여러 요인으로 인해, 전극 리드와 버스바 사이에 간격이 발생하더라도, 전극 리드 사이 및/또는 전극 리드와 버스바 사이의 용접력이 안정적으로 유지된다는 점을 알 수 있다.Therefore, in the case of the battery module according to the present invention, even if there is a gap between the electrode leads and the bus bar due to various factors such as process limitations, errors, interferences such as impurities during the manufacturing process, And the bus bar can be stably maintained.
도 23은, 본 발명의 또 다른 실시예에 따른 배터리 모듈에서, 전극 리드에 구비된 다수의 용접 스팟의 구성을 개략적으로 나타내는 도면이다. 이를테면, 도 23은, 도 4의 B2 부분에 대한 확대 구성의 또 다른 예라 할 수 있다. 본 실시예의 경우, 앞선 실시예와 차이점이 있는 부분만을 위주로 설명하며, 앞선 실시예에 대한 설명이 동일 또는 유사하게 적용될 수 있는 부분에 대해서는 상세한 설명을 생략한다.23 is a view schematically showing a configuration of a plurality of welding spots provided in an electrode lead in a battery module according to another embodiment of the present invention. For example, FIG. 23 is another example of the enlarged configuration for the portion B2 in FIG. In the case of the present embodiment, only the differences from the previous embodiments will be mainly described, and the detailed description of the parts that can be applied to the same or similar parts of the previous embodiments will be omitted.
도 23을 참조하면, 하나의 전극 리드에 3개의 용접 스팟(Wd, We, Wf)이 포함되어 있으며, 각각의 용접 스팟은, 나선 형태의 2개의 용접 라인을 구비하는 토네이도 형태로 구성될 수 있다.23, three electrode spots Wd, We, and Wf are included in one electrode lead, and each of the welding spots may be configured in the form of a tornado having two welding lines in a spiral form .
특히, 본 실시예에서, 둘 이상의 용접 스팟은, 외측 단부를 연결하는 직선이 서로 다른 방향으로 형성되도록 구성될 수 있다. 보다 구체적으로, 도 23의 구성에서, 3개의 용접 스팟(Wd, We, Wf)은, 각각의 외측 단부를 연결하는 직선이 서로 다른 방향으로 형성될 수 있다. 예를 들어, 도 23에 도시된 바와 같이, 용접 스팟 Wd에 대하여 2개의 용접 라인(Wd1, Wd2)의 외측 단부를 연결하는 직선을 C5라 하고, 용접 스팟 We에 대하여 2개의 용접 라인(We1, We2)의 외측 단부를 연결하는 직선을 C6이라 하며, 용접 스팟 Wf에 대하여 2개의 용접 라인(Wf1, Wf2)의 외측 단부를 연결하는 직선을 C7이라 한다. 이때, 직선 C5, C6 및 C7은 서로 평행하지 않도록 구성될 수 있다. 이를테면, 직선 C6는 직선 C5에 대하여 대략 30도 각도로 기울어진 형태로 구성될 수 있고, 직선 C7은 직선 C5에 대하여 대략 60도 각도로 기울어진 형태로 구성될 수 있다. 이러한 구성은, 하나의 전극 리드에 구비된 적어도 둘 이상의 용접 스팟이, 서로 완전히 동일한 형태로 형성되지 않고, 용접 스팟의 중심점을 기준으로, 0도보다 크고 360보다 작은 범위 내에서, 일정 각도 회전한 형태로 구성되어 있다고 할 수 있다.In particular, in this embodiment, two or more weld spots may be configured so that the straight lines connecting the outer ends are formed in different directions. More specifically, in the configuration of Fig. 23, the straight lines connecting the respective outer ends of the three welding spots Wd, We, Wf may be formed in different directions. 23, a straight line connecting the outer ends of the two welding lines Wd1 and Wd2 to the welding spot Wd is referred to as C5 and two straight lines connecting the two welding lines We1, A straight line connecting the outer ends of the two welding lines Wf1 and Wf2 with respect to the welding spot Wf is referred to as C7. At this time, the straight lines C5, C6, and C7 may be configured so as not to be parallel to each other. For example, the straight line C6 may be configured to be inclined at an angle of about 30 degrees with respect to the straight line C5, and the straight line C7 may be configured to be inclined at an angle of about 60 degrees with respect to the straight line C5. In such a configuration, at least two or more welding spots provided in one electrode lead are not formed in exactly the same shape as each other, but are arranged in a range of more than 0 degrees and smaller than 360, It can be said that
특히, 하나의 전극 리드에 다수, 이를테면 4개 이상의 용접 스팟이 형성된 경우, 각 용접 스팟의 외측 단부 연결 직선은 모든 용접 스팟에 대하여 서로 평행하지 않도록 구성될 수 있다. 즉, 하나의 전극 리드 내에서 모든 용접 스팟은 서로 동일하게 형성되지 않고, 중심점을 기준으로 서로 소정 각도 회전한 형태로 구성될 수 있다.In particular, when a plurality of, for example, four or more, welding spots are formed in one electrode lead, the outer end connecting straight line of each welding spot may be configured so as not to be parallel to each other for all the welding spots. That is, all of the welding spots within one electrode lead are not formed to be equal to each other but may be configured to be rotated at a predetermined angle with respect to the center point.
본 발명의 이와 같은 구성에 의하면, 어느 방향으로 인장력이 가해지더라도, 전극 리드 사이 및/또는 전극 리드와 버스바 사이의 용접성이 안정적으로 확보될 수 있다. 즉, 상기와 같은 실시 구성의 경우, 다수의 용접 스팟에 대하여, 외측 단부에서 용접 라인의 진행 방향이 서로 다르게 형성된다고 할 수 있다. 따라서, 이 경우, 특정 방향으로 스트레스가 가해진다 하더라도, 각 용접 스팟마다 외측 단부의 피로도가 달라질 수 있으며, 용접성이 강하게 유지되는 용접 스팟이 존재할 수 있게 마련이다. 그러므로, 전극 리드에 대한 인장력이 어느 방향으로 작용하더라도, 용접성이 안정적으로 확보되는 장점을 가질 수 있다.According to this structure of the present invention, the weldability between the electrode leads and / or the electrode leads and the bus bar can be stably ensured regardless of the direction in which the tensile force is applied. In other words, in the case of the above-described embodiment, it can be said that the welding direction of the welding line at the outer end portion is formed differently for a plurality of welding spots. Therefore, in this case, even if the stress is applied in a specific direction, the fatigue of the outer end of each welding spot can be changed, and there can be a welding spot where the welding property is strongly maintained. Therefore, regardless of the direction in which the tensile force acts on the electrode leads, the weldability can be stably secured.
이상과 같이, 본 발명은 비록 한정된 실시예와 도면에 의해 설명되었으나, 본 발명은 이것에 의해 한정되지 않으며 본 발명이 속하는 기술분야에서 통상의 지식을 가진 자에 의해 본 발명의 기술사상과 아래에 기재될 특허청구범위의 균등범위 내에서 다양한 수정 및 변형이 가능함은 물론이다.While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be understood that various modifications and changes may be made without departing from the scope of the appended claims.
[부호의 설명][Description of Symbols]
10: 전극 리드10: Electrode lead
20: 버스바20: bus bar
100: 셀 어셈블리100: cell assembly
110: 이차 전지110: secondary battery
111: 전극 리드111: electrode lead
200: 버스바200: bus bar
W: 용접 스팟W: Weld spot
W1: 제1 용접 라인, W2: 제2 용접 라인W1: first welding line, W2: second welding line

Claims (11)

  1. 적어도 일 방향으로 적층되고 각각 전극 리드를 구비하며, 상기 전극 리드 간 연결을 통해 상호 전기적으로 연결된 다수의 이차 전지를 구비하는 셀 어셈블리; 및A cell assembly comprising: a plurality of secondary cells stacked in at least one direction and each having an electrode lead and electrically connected to each other through a connection between the electrode leads; And
    전기 전도성 재질로 구성되어 상기 이차 전지의 전극 리드와 접촉하여 전기적으로 연결된 하나 이상의 버스바And at least one bus bar which is made of an electrically conductive material and is electrically connected to the electrode lead of the secondary battery,
    를 포함하고, Lt; / RTI >
    적어도 하나의 전극 리드는, 접촉된 다른 전극 리드 및 접촉된 버스바 중 적어도 하나와, 토네이도 형태로 형성된 용접 스팟에 의해 결합 고정된 것을 특징으로 하는 배터리 모듈.Wherein at least one electrode lead is coupled and fixed to at least one of the other electrode leads and the contact bus bar that are contacted by a welding spot formed in the form of a tornado.
  2. 제1항에 있어서,The method according to claim 1,
    상기 용접 스팟은, 나선 형태의 복수의 용접 라인을 구비하는 형태로 구성된 것을 특징으로 하는 배터리 모듈.Wherein the welding spot is configured to have a plurality of spiral weld lines.
  3. 제2항에 있어서,3. The method of claim 2,
    상기 용접 스팟은, 상기 복수의 용접 라인이 서로 동일한 회전 방향을 가지며, 하나의 용접 라인의 적어도 일부가 다른 용접 라인 사이에 삽입된 형태로 구성된 것을 특징으로 하는 배터리 모듈.Wherein the welding spot is configured such that the plurality of welding lines have the same rotational direction as each other and at least a part of one welding line is inserted between the other welding lines.
  4. 제2항에 있어서,3. The method of claim 2,
    상기 용접 스팟은, 복수의 용접 라인의 각 내측 단부를 연결하는 직선 및 각 외측 단부를 연결하는 직선이 서로 평행하도록 구성된 것을 특징으로 하는 배터리 모듈.Wherein the welding spot is formed so that a straight line connecting each inner end of the plurality of welding lines and a straight line connecting each of the outer ends are parallel to each other.
  5. 제2항에 있어서,3. The method of claim 2,
    상기 용접 스팟은, 복수의 용접 라인의 내측 단부가 서로 연결되도록 구성된 것을 특징으로 하는 배터리 모듈.Wherein the weld spots are configured such that inner ends of a plurality of welding lines are connected to each other.
  6. 제1항에 있어서,The method according to claim 1,
    상기 용접 스팟은, 하나의 전극 리드에 대하여 다수 구비된 것을 특징으로 하는 배터리 모듈.Wherein the plurality of welding spots are provided for one electrode lead.
  7. 제6항에 있어서,The method according to claim 6,
    하나의 전극 리드에 구비된 다수의 용접 스팟은, 외측 단부가 하나의 직선 상에 위치하도록 구성된 것을 특징으로 하는 배터리 모듈.Wherein a plurality of welding spots provided in one electrode lead are configured such that an outer end thereof is positioned on one straight line.
  8. 제1항에 있어서,The method according to claim 1,
    상기 용접 스팟은, 상호 적층된 다수의 전극 리드 및 1개의 버스바를 용접하도록 구성된 것을 특징으로 하는 배터리 모듈.Wherein the welding spot is configured to weld a plurality of mutually stacked electrode leads and one bus bar.
  9. 제1항에 있어서,The method according to claim 1,
    상기 전극 리드는, 내측 방향으로 오목하게 형성된 오목부를 구비하고,Wherein the electrode lead has a concave portion formed concavely in an inward direction,
    상기 용접 스팟은, 적어도 일부가 상기 오목부에 위치하는 것을 특징으로 하는 배터리 모듈.Wherein the welding spot is located at least partially in the recess.
  10. 제1항 내지 제9항 중 어느 한 항에 따른 배터리 모듈을 포함하는 배터리 팩.A battery pack comprising the battery module according to any one of claims 1 to 9.
  11. 제1항 내지 제9항 중 어느 한 항에 따른 배터리 모듈을 포함하는 자동차.An automobile comprising a battery module according to any one of claims 1 to 9.
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CN111426685A (en) * 2020-03-20 2020-07-17 合肥国轩高科动力能源有限公司 Detection method for lithium battery laser welding
CN114868303A (en) * 2019-11-20 2022-08-05 Sk新能源株式会社 Battery module

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