CN216120653U

CN216120653U - Battery monomer, battery and consumer

Info

Publication number: CN216120653U
Application number: CN202122531343.9U
Authority: CN
Inventors: 方堃; 郭志君
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2021-10-20
Filing date: 2021-10-20
Publication date: 2022-03-22
Anticipated expiration: 2031-10-20

Abstract

The application relates to a battery monomer, a battery and electric equipment. The battery cell includes: a housing including a wall portion provided with an electrode lead-out hole; an electrode assembly disposed inside the case, the electrode assembly having a first tab formed at an end facing the wall portion; the electrode terminal comprises a terminal body and a first flange, wherein the terminal body is arranged in the electrode leading-out hole in a penetrating mode, the first flange protrudes out of the outer peripheral surface of the terminal body along the radial direction of the terminal body, and the first flange is located on the inner side of the wall portion to limit the electrode terminal to move along the direction departing from the electrode assembly; a first current collecting member between the wall portion and the electrode assembly for connecting the electrode terminal and the first tab; the terminal body is provided with a first end face facing the first current collecting member, the first end face is provided with a groove and a connecting area used for being connected with the first current collecting member, and the groove is located between the connecting area and the first flange.

Description

Battery monomer, battery and consumer

Technical Field

The application relates to the technical field of batteries, in particular to a battery monomer, a battery and electric equipment.

Background

Under the environment of pursuing energy conservation and emission reduction, the battery is widely applied to electric equipment such as mobile phones, computers, electric vehicles and the like, and provides electric energy for the electric equipment. The overcurrent capacity and the service life of the battery are positively correlated with the performance of the electric equipment, and how to improve the overcurrent capacity and the service life of the battery is an important research and development direction in the field.

SUMMERY OF THE UTILITY MODEL

The application aims at providing a battery monomer, a battery and electric equipment to improve the overcurrent capacity and the service life of the battery.

The embodiment of the application is realized as follows:

in a first aspect, an embodiment of the present application provides a battery cell, which includes: a housing including a wall portion, the wall portion having an electrode lead-out hole; an electrode assembly disposed inside the case, the electrode assembly having a first tab formed at an end facing the wall portion; the electrode terminal comprises a terminal body and a first flange, the terminal body is arranged in the electrode leading-out hole in a penetrating mode, the first flange protrudes out of the outer peripheral surface of the terminal body along the radial direction of the terminal body, and the first flange is located on the inner side of the wall portion so as to limit the electrode terminal to move along the direction departing from the electrode assembly; a first current collecting member between the wall and the electrode assembly for connecting the electrode terminal and the first tab; the terminal body is provided with a first end face facing the first current collecting member, the first end face is provided with a groove and a connecting area used for being connected with the first current collecting member, and the groove is located between the connecting area and the first flange.

Among the technical scheme that this application provided, be provided with the recess between joining region and first flange, the stress that first flange received can be released to the recess, the stress transmission that avoids first flange to receive leads to the joining region to warp, the roughness of joining region has been guaranteed, and then improve the connection reliability of joining region and first mass flow component, avoid the connection failure between electrode terminal and the first mass flow component, prevent the disconnection of free internal circuit of battery, guarantee to flow over steadily between electrode terminal and the first mass flow component, the free ability and the life of overflowing of battery have been improved.

In one embodiment of the application, the recess is an annular groove arranged around the connection region.

In the technical scheme, the connecting area is surrounded by the groove, or the groove is surrounded on the first end face, and the connecting area is formed in the region surrounded by the groove so as to limit the stress in any direction to be transferred to the connecting area and ensure the flatness of the connecting area.

In one embodiment of the present application, the electrode assembly is a winding type structure, and the first current collecting member covers a winding center hole of the electrode assembly.

In the technical scheme, the position of the first current collecting member, which is used for being connected with the connecting area, is exposed to the winding center hole, and the welding tool can be used for penetrating through the winding center hole to weld the first current collecting member to the connecting area, so that the welding stamp is positioned inside the battery cell, the welding stamp is prevented from being exposed outside, the welding stamp is prevented from being oxidized and rusted by outside air, and the service life of the battery is prolonged.

In one embodiment of the present application, the first current collecting member includes a current collecting body, and a protrusion protruding from the current collecting body in a direction toward the electrode terminal, the protrusion corresponding to a winding center hole of the electrode assembly and being adapted to be connected to the connection region, the current collecting body being adapted to be connected to the first tab.

In above-mentioned technical scheme, through setting up the convex part that exceeds the mass flow body, prevent that the structure outside the joining region of mass flow body and electrode terminal from interfering, guarantee convex part close contact joining region, can also be through coiling central hole to convex part application of force or welding to make convex part and joining region zonulae occludens, further improve the joint strength and the connection area of first mass flow component and joining region, realize stably overflowing, improve the ability of overflowing and the life of battery.

In one embodiment of the present application, the outer diameter of the groove is larger than the diameter of the protrusion.

The outer diameter of the groove refers to the diameter of the outer groove wall of the groove, and in the technical scheme, along the direction of the central axis of the terminal body, the projection of the convex part on the first end face falls within the area surrounded by the outer groove wall, so that the convex part is prevented from interfering with structures outside the connection area, and the convex part and the connection area are ensured to be in gapless and tight connection.

In one embodiment of the present application, the inner diameter of the groove is smaller than the diameter of the protrusion.

In the above technical solution, the inner diameter of the groove refers to the diameter of the inner groove wall of the groove, and by making the diameter of the inner groove wall of the groove smaller than the diameter of the protrusion, it is ensured that the connection area is completely covered by the protrusion, the connection area is maximally utilized, and the flow area is maximally ensured.

In one embodiment of the present application, the protrusion includes an end wall and a peripheral wall, the peripheral wall is disposed around the end wall, the peripheral wall is connected to the current collecting body, the end wall is connected to the connection region, and the peripheral wall and the end wall together define a cavity.

In the above-described aspect, by providing the surface of the projection facing away from the wall as a cavity, the cavity identifies the position of the projection on the surface of the first current collecting member facing away from the wall, so as to weld the end wall and the connection region from the side of the first current collecting member facing away from the wall. The cavity is also used for positioning the welding head so as to prevent the welding head from deviating and ensure that the convex part is stably connected with the connecting area. Compared with the situation that the cavity is not arranged on the back surface of the convex part, the thickness of the end wall is reduced by arranging the cavity, and penetration welding is facilitated.

In one embodiment of the present application, the diameter of the cavity is greater than the diameter of the winding center hole.

In the technical scheme, the concave cavity completely covers one end of the winding center hole, the welding head cannot interfere with the flow collecting body after penetrating through the winding center hole, and the welding head can smoothly enter the concave cavity to weld the end wall and the connecting area. And under the condition that the diameter of the concave cavity is fixed, the diameter of the winding center hole of the electrode assembly is reduced to be smaller than that of the concave cavity, so that the space occupation ratio of the electrode assembly is increased, and the energy density of the battery monomer is improved.

In one embodiment of the present application, a side of the electrode terminal facing the first current collecting member is formed with a slope inclined with respect to a plane perpendicular to a central axis direction of the electrode terminal and extending from an outer groove wall of the groove in a direction approaching the electrode assembly.

In the technical scheme, the inclined surface is arranged on the periphery of the outer groove wall of the groove to avoid the first current collecting component, and the first current collecting component is guided to move towards the connecting area, so that the first current collecting component is accurately positioned, and the first current collecting component is ensured to be connected to the connecting area.

In one embodiment of the present application, the electrode terminal further includes a second flange protruding from an outer circumferential surface of the terminal body in a radial direction of the terminal body, the second flange being located outside the wall portion to restrict the electrode terminal from moving in a direction toward the electrode assembly.

In the technical scheme, under the combined action of the first flange and the second flange, the electrode terminal is limited to move along the central axis of the terminal body, so that the electrode terminal is axially positioned, the electrode terminal is prevented from axially shaking, and the stable connection of the electrode terminal and the first current collecting component is further ensured.

In one embodiment of the present application, the battery cell further includes an insulating member disposed between the electrode terminal and the wall portion to insulate and separate the electrode terminal and the wall portion.

In above-mentioned technical scheme, through setting up the insulating part to wall portion is electrified, reduces the short circuit risk, and then improves single security of battery and life.

In one embodiment of the present application, a side of the second flange facing the wall portion is formed with an annular projection disposed around a central axis of the electrode terminal, the annular projection being configured to press a portion of the insulator between the second flange and the wall portion.

In the technical scheme, the insulating piece is extruded through the annular protrusion to form the annular sealing area between the second flange and the wall part, so that liquid leakage from a gap between the electrode terminal and the wall part is prevented, and the service life of the battery cell is prolonged.

In one embodiment of the application, a projection of the first flange on the second flange covers the annular protrusion in a thickness direction of the wall portion.

In the technical scheme, the first flange is supported on the inner side of the wall part so as to prevent the wall part from being deformed by the extrusion of the annular bulge on the outer side, and the wall part and the annular bulge are matched to extrude the insulating part, so that a gap between the electrode terminal and the wall part is eliminated, and the sealing effect is improved.

In an embodiment of the present application, the housing includes a casing body and an end cover, the casing body includes a bottom wall and a side wall, the side wall is enclosed around the bottom wall, one end of the side wall is connected with the bottom wall, the other end of the side wall encloses an opening opposite to the bottom wall, the end cover covers the opening, and the wall portion is the bottom wall or the end cover.

In above-mentioned technical scheme, the wall portion can be the end cover, and the wall portion also can be the diapire of casing, no matter electrode terminal sets up in end cover or the diapire of casing, can both guarantee the roughness of connecting region.

In one embodiment of the present application, the electrode terminal is insulated from the wall portion, and a second tab having an opposite polarity to the first tab is formed at an end of the electrode assembly away from the wall portion; the battery cell also includes a second current collecting member for electrically connecting the second tab and the wall portion.

In the technical scheme, the electrode terminal and the wall part are positioned at the same end of the battery cell, and the electrode terminal and the wall part are charged in different polarities, so that the bus members with opposite polarities can be connected at the same end of the battery cell, and the assembly and the connection are convenient.

In a second aspect, an embodiment of the present application provides a battery, which includes the foregoing battery cell.

In a third aspect, an embodiment of the present application provides an electric device, which includes the foregoing battery.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

FIG. 1 is a structural illustration of a vehicle according to an embodiment of the present application;

fig. 2 is an exploded view of a battery provided in an embodiment of the present application;

fig. 3 is a perspective view of a battery cell according to an embodiment of the present disclosure;

fig. 4 is an exploded view of a battery cell according to an embodiment of the present disclosure;

fig. 5 is a cross-sectional view of a battery cell according to an embodiment of the present disclosure;

fig. 6 is a schematic view illustrating an electrical connection structure between an electrode terminal and a first tab according to an embodiment of the present disclosure;

fig. 7 is a perspective view of an electrode terminal according to an embodiment of the present application;

fig. 8 is a schematic plan view of a side of an electrode terminal facing a first current collecting member according to an embodiment of the present application;

fig. 9 is a schematic plan view of a side of an electrode terminal facing a first current collecting member according to another embodiment of the present application;

fig. 10 is a schematic plan view of a side of an electrode terminal facing a first current collecting member according to still another embodiment of the present application;

fig. 11 is a schematic plan view of a side of an electrode terminal facing a first current collecting member according to still another embodiment of the present application;

fig. 12 is a perspective view of a first current collecting member provided in an embodiment of the present application;

fig. 13 is a cross-sectional view of a first current collecting member according to an embodiment of the present application;

FIG. 14 is an enlarged view of portion A of FIG. 5;

fig. 15 is a schematic flow chart illustrating a method for manufacturing a battery cell according to an embodiment of the present disclosure;

fig. 16 is a schematic view illustrating a welding process of a first current collecting member and a connection region according to an embodiment of the present application;

fig. 17 is a schematic block diagram of a device for manufacturing a battery cell according to an embodiment of the present disclosure;

fig. 18 is a schematic flow chart illustrating an assembly method of a housing and an electrode terminal according to an embodiment of the present disclosure;

fig. 19 is a schematic structural diagram of an initial state of a housing and an electrode terminal according to an embodiment of the present application;

fig. 20 is a schematic view illustrating an assembly process of a housing and an electrode terminal according to an embodiment of the present disclosure;

fig. 21 is a schematic structural view illustrating the assembly of the housing and the electrode terminal according to an embodiment of the present disclosure;

fig. 22 is a schematic block diagram of an assembly apparatus of a housing and an electrode terminal according to an embodiment of the present disclosure.

Icon: 1000-a vehicle; 100-a battery; 101-a box body; 1011-a first tank portion; 1012-a second tank portion; 1-a battery cell; 11-a housing; 11 a-a wall portion; 11 b-electrode exit holes; 111-a housing; 1111-side wall; 1112-a bottom wall; 112-an end cap; 12-an electrode assembly; 121-a body portion; 122 — a first tab; 123-a second tab; 124-winding the central hole; 13-an electrode terminal; 131-a terminal body; 1311-first end face; 13111-a linker region; 13112-grooves; 13112 a-inner slot wall; 13112 b-outer slot wall; 132-a first flange; 133-inclined plane; 134-a second flange; 1341-an annular projection; 14-a first current collecting member; 141-a current collecting body; 142-a convex part; 1421-peripheral wall; 1422-end wall; 1423-cavity; 15-a second current collecting member; 151-through holes; 16-an insulator; 161-a first portion; 162-a second portion; 163-third section; 200-a motor; 300-a controller; 400-a preparation device; 401-a first providing device; 402-a second providing means; 403-a third providing device; 404-a fourth providing means; 405-a first assembly device; 406-a second assembly means; 407-a third assembly means; 4071-a welding unit; 408-a fourth assembly means; 500-assembling the device; 501-fifth providing device; 502-a sixth providing means; 503-a fifth assembly device; 5031-a heading press mechanism; d1-outer diameter of groove; d2-inner diameter of groove; d3-diameter of lobe; d4-diameter of the concavity; d5 — diameter of coiled center hole; p-the direction of the central axis of the terminal body; r-radial of the terminal body.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description of the application in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "including" and "having," and any variations thereof, in the description and claims of this application and the description of the above figures are intended to cover non-exclusive inclusions. The terms "first," "second," and the like in the description and claims of this application or in the above-described drawings are used for distinguishing between different elements and not for describing a particular sequential or chronological order.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "attached" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

The term "and/or" in this application is only one kind of association relationship describing the associated object, and means that there may be three kinds of relationships, for example, a and/or B, which may mean: there are three cases of A, A and B, and B. In addition, the character "/" in this application generally indicates that the former and latter related objects are in an "or" relationship.

In the embodiments of the present application, like reference numerals denote like parts, and a detailed description of the same parts is omitted in different embodiments for the sake of brevity. It should be understood that the thickness, length, width and other dimensions of the various components in the embodiments of the present application and the overall thickness, length, width and other dimensions of the integrated device shown in the drawings are only exemplary and should not constitute any limitation to the present application.

The appearances of "a plurality" in this application are intended to mean more than two (including two).

In this application, the battery cell may include a lithium ion secondary battery cell, a lithium ion primary battery cell, a lithium sulfur battery cell, a sodium lithium ion battery cell, a sodium ion battery cell, or a magnesium ion battery cell, and the embodiment of the present application is not limited thereto.

Reference to a battery in embodiments of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in the present application may include a battery module or a battery pack, etc. Batteries generally include a case for enclosing one or more battery cells. The box can avoid liquid or other foreign matters to influence the charging or discharging of battery monomer.

The battery cell includes an electrode assembly and an electrolyte, the electrode assembly including a positive electrode tab, a negative electrode tab, and a separator. The battery cell mainly depends on metal ions to move between the positive pole piece and the negative pole piece to work. The positive pole piece comprises a positive current collector and a positive active substance layer, and the positive active substance layer is coated on the surface of the positive current collector; the positive current collector comprises a positive current collecting part and a positive electrode lug, wherein the positive current collecting part is coated with a positive active substance layer, and the positive electrode lug is not coated with the positive active substance layer. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, the positive electrode active material layer includes a positive electrode active material, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative pole piece comprises a negative pole current collector and a negative pole active substance layer, and the negative pole active substance layer is coated on the surface of the negative pole current collector; the negative current collector comprises a negative current collecting part and a negative electrode lug, wherein the negative current collecting part is coated with a negative active material layer, and the negative electrode lug is not coated with the negative active material layer. The material of the negative electrode current collector may be copper, the negative electrode active material layer includes a negative electrode active material, and the negative electrode active material may be carbon, silicon, or the like. The material of the spacer may be PP (polypropylene) or PE (polyethylene).

The battery cell further includes a case for accommodating the electrode assembly, and electrode terminals mounted to the case for electrically connecting to the electrode assembly to enable charging and discharging of the electrode assembly.

The battery unit further comprises a current collecting member for electrically connecting the tab of the battery unit and the electrode terminal to transmit electric energy from the electrode assembly to the electrode terminal and to the outside of the battery unit through the electrode terminal; the plurality of battery cells are electrically connected through the confluence part so as to realize series connection, parallel connection or series-parallel connection of the plurality of battery cells.

The current collecting component is an important part for realizing stable current transmission of the single battery, and the damage or poor connection of the connection part of the current collecting component, the lug and the electrode terminal can cause the unstable overcurrent of the single battery and easily cause the increase of internal resistance of the connection part to generate heat and damage, thereby influencing the service life of the battery. The inventors have noticed that the end surface of the end of the electrode terminal located inside the case is used for connection with the current collecting member, and thus the flatness of the end surface of the electrode terminal is an important factor for securing stable connection of the electrode terminal with the current collecting member, and the end surface of the electrode terminal is easily deformed by the force applied to the outer circumference of the electrode terminal.

In view of this, the embodiment of the present application provides a technical solution, in which the electrode terminal includes a terminal body and a first flange, the terminal body is inserted through a wall portion of the housing, the first flange protrudes out of an outer circumferential surface of the terminal body along a radial direction of the terminal body, the first flange is located inside the wall portion (i.e., inside the housing), the first flange directly or indirectly abuts against the inside of the wall portion to limit the electrode terminal from moving to an outside of the wall portion, the terminal body has a first end surface facing the current collecting member, the first end surface is provided with a groove and a connecting region, the groove is located between the connecting region and the first flange, the groove can release stress applied to the first flange, so that the stress applied to the first flange is prevented from being transmitted to the connecting region, the connecting region is ensured to be flat and not deformed, thereby ensuring reliable connection between the electrode terminal and the current collecting member, avoiding connection failure between the electrode terminal and the first current collecting member, and preventing an internal circuit of the battery cell from being disconnected, so as to ensure stable overcurrent between the electrode terminal and the first current collecting component, thereby improving the overcurrent capacity and prolonging the service life of the battery monomer.

The technical scheme described in the embodiment of the application is suitable for the battery and the electric equipment using the battery.

The electric equipment can be vehicles, mobile phones, portable equipment, notebook computers, ships, spacecrafts, electric toys, electric tools and the like. The vehicle can be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extended vehicle and the like; spacecraft include aircraft, rockets, space shuttles, and spacecraft, among others; electric toys include stationary or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric airplane toys, and the like; the electric power tools include metal cutting electric power tools, grinding electric power tools, assembly electric power tools, and electric power tools for railways, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, electric impact drills, concrete vibrators, and electric planers. The embodiment of the present application does not specifically limit the above-mentioned electric devices.

For convenience of explanation, the following embodiments will be described by taking an electric device as an example of a vehicle.

As shown in fig. 1, a vehicle 1000 according to an embodiment of the present disclosure is illustrated, where the vehicle 1000 may be a fuel-oil vehicle, a gas-fired vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid electric vehicle, or an extended range vehicle. The vehicle 1000 may be provided with a battery 100, a controller 300, and a motor 200 inside, and the controller 300 is configured to control the battery 100 to supply power to the motor 200. For example, the battery 100 may be provided at the bottom or the head or tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may be used as an operation power supply of the vehicle 1000 for a circuit system of the vehicle 1000, for example, for power demand for operation in starting, navigation, and running of the vehicle 1000. In another embodiment of the present application, the battery 100 may be used not only as an operating power source of the vehicle 1000, but also as a driving power source of the vehicle 1000, instead of or in part of fuel or natural gas, to provide driving power to the vehicle 1000.

In order to meet different power requirements, as shown in fig. 2, the battery 100 may include a plurality of battery cells 1, wherein the plurality of battery cells 1 may be connected in series or in parallel or in series-parallel, and the series-parallel refers to a mixture of series connection and parallel connection. Battery 100 may also be referred to as a battery 100 pack. Alternatively, a plurality of battery cells 1 may be connected in series or in parallel or in series-parallel to form a battery module, and a plurality of battery modules may be connected in series or in parallel or in series-parallel to form the battery 100. That is, the plurality of battery cells 1 may be directly assembled into the battery 100, or may be assembled into a battery module and then assembled into the battery 100.

The battery 100 may further include a case 101 (or a cover), the inside of the case 101 is a hollow structure, and the plurality of battery cells 1 are accommodated in the case 101. The housing 101 may comprise two parts for receiving (see also fig. 2), here referred to as a first housing part 1011 and a second housing part 1012, respectively, the first housing part 1011 and the second housing part 1012 being snap-fitted together. The shape of the first housing portion 1011 and the second housing portion 1012 may be determined according to the shape of the combination of the plurality of battery cells 1, and the first housing portion 1011 and the second housing portion 1012 may each have one opening. For example, each of the first casing 1011 and the second casing 1012 may be a hollow rectangular parallelepiped, only one surface of each of the first casing 1011 and the second casing 1012 may be an open surface, the opening of the first casing 1011 and the opening of the second casing 1012 may be disposed to face each other, and the first casing 1011 and the second casing 1012 may be engaged with each other to form the casing 101 having a closed chamber. One of the first casing 1011 and the second casing 1012 may be a rectangular parallelepiped having an opening, and the other may be a cover plate structure for closing the opening of the rectangular parallelepiped. The plurality of battery cells 1 are connected in parallel or in series-parallel combination and then placed in the case 101 formed by fastening the first case portion 1011 and the second case portion 1012.

Optionally, battery 100 may also include other structures. For example, the battery 100 may further include a bus member (not shown) for electrically connecting the plurality of battery cells 1, such as parallel connection, series connection, or series-parallel connection. Specifically, the bus member may achieve electrical connection between the battery cells 1 by connecting the electrode terminals 13 of the battery cells 1. Further, the bus bar member may be fixed to the electrode terminals 13 of the battery cells 1 by welding. The electric energy of the plurality of battery cells 1 can be further led out through the case 101 by the conductive mechanism. Alternatively, the conductive means may also belong to the bus bar member.

As described in detail with respect to any one of the battery cells 1, as shown in fig. 3, 4, 5, and 6, the battery cell 1 includes an electrode assembly 12, a case 11, an electrode terminal 13, and a first current collecting member 14. As shown in fig. 4 and 5, the case 11 includes a wall portion 11a, the wall portion 11a is provided with an electrode lead-out hole 11b, the electrode assembly 12 is disposed inside the case 11, and one end of the electrode assembly 12 facing the wall portion 11a is formed with a first tab 122. As shown in fig. 6, the electrode terminal 13 includes a terminal body 131 and a first flange 132, the terminal body 131 is inserted into the electrode drawing hole 11b, the first flange 132 protrudes from the outer circumferential surface of the terminal body 131 in the radial direction R of the terminal body, and the first flange 132 is located inside the wall portion 11a to restrict the movement of the electrode terminal 13 in a direction away from the electrode assembly 12. The first current collecting member 14 is located between the wall portion 11a and the electrode assembly 12 for connecting the electrode terminal 13 and the first tab 122. Wherein the terminal body 131 has a first end surface 1311 facing the first current collecting member 14, the first end surface 1311 being provided with a groove 13112 and a connection region 13111 for connection with the first current collecting member 14, the groove 13112 being located between the connection region 13111 and the first flange 132.

The electrode assembly 12 includes a first pole piece, a second pole piece, and a separator for separating the first pole piece and the second pole piece. The first and second pole pieces have opposite polarities, that is, one of the first and second pole pieces is a positive pole piece, and the other of the first and second pole pieces is a negative pole piece. The first pole piece, the second pole piece and the spacer are prior art, and although not shown in the drawings of the present application, those skilled in the art should understand the specific structure. The electrode assembly 12 includes a body portion 121, a first tab 122, and a second tab 123, the first tab 122 and the second tab 123 protruding from the body portion 121, when viewed from the external shape of the electrode assembly 12. The first tab 122 is the portion of the first pole piece not coated with the active material layer, and the second tab 123 is the portion of the second pole piece not coated with the active material layer. The first tab 122 and the second tab 123 may extend from the same side of the body 121, or may extend from opposite sides. Illustratively, as shown in fig. 4 and 5, the first tab 122 and the second tab 123 are respectively disposed at both ends of the body part 121, that is, the first tab 122 and the second tab 123 are respectively located at both ends of the electrode assembly 12.

The case 11 has a hollow structure, and a space for accommodating the electrode assembly 12 is formed inside thereof. The shape of the case 11 may be determined according to the specific shape of the electrode assembly 12. For example, if the electrode assembly 12 is of a cylindrical structure, the case 11 may be selected as a cylindrical case; if the electrode assembly 12 has a rectangular parallelepiped structure, a rectangular parallelepiped case can be used as the case 11. Alternatively, both the electrode assembly 12 and the case 11 are cylindrical. The wall 11a is an end wall of one end of the case 11, the wall 11a facing the first tab 122 of the electrode assembly 12, and the end of the case 11 remote from the wall 11a facing the second tab 123 of the electrode assembly 12.

The electrode lead-out hole 11b penetrates the wall portion 11a so that the inside of the wall portion 11a communicates with the outside of the wall portion 11a, the inside of the wall portion 11a is the inside of the case 11, and the outside of the wall portion 11a is the outside of the case 11.

The electrode terminal 13 is mounted to the electrode drawing hole 11b for accomplishing the electrical connection of the first tab 122 of the electrode assembly 12 and the external bus member.

The fact that the terminal body 131 is inserted into the electrode lead-out hole 11b means that one end of the terminal body 131 is located inside the housing 11 and the other end is located outside the housing 11, that is, both ends of the terminal body 131 are located on both sides of the wall portion 11 a. One end of the terminal body 131 located inside the wall portion 11a is used for connecting the first tab 122, and one end of the terminal body 131 located outside the wall portion 11a is used for connecting an external bus member. The shape of the terminal body 131 is not limited, and may be a cylinder, a polygonal cylinder, or another irregular cylinder. Alternatively, the terminal body 131 is cylindrical in shape.

The first end surface 1311 is an end surface of the terminal body 131 at an end located inside the wall portion 11a, and the connection region 13111 is a middle region of the first end surface 1311. In the region between the first flange 132 and the connection region 13111, a groove 13112 is formed recessed from the first end surface 1311 in the center axis direction P of the terminal body.

The center axis of the terminal body 131 is perpendicular to the first end surface 1311, the center axis direction P of the terminal body is visible in fig. 6, and the radial direction R of the terminal body refers to a direction perpendicular to the center axis direction P of the terminal body.

The first flange 132 is a protrusion provided on the outer circumferential surface of the terminal body 131, that is, the first flange 132 protrudes from the outer circumferential surface of the terminal body 131 with respect to the radial direction R of the terminal body. The first flange 132 is located at one end of the terminal body 131 located at the inner side of the wall 11a, and the first flange 132 directly or indirectly abuts against the wall 11a to prevent the terminal body 131 from moving to the outer side of the wall 11a, so as to prevent the terminal body 131 from being away from the electrode assembly 12 and from being separated from the wall 11 a. The terminal body 131 and the first flange 132 may be integrally formed, or may be formed as two parts that are connected by welding, bonding, or the like after being formed separately. Alternatively, the first flange 132 is integrally formed with the terminal body 131. The first current collecting member 14 is located between the first tab 122 and the wall portion 11a, and a surface of the first current collecting member 14 facing the electrode assembly 12 is electrically connected to the first tab 122, and a surface of the first current collecting member 14 facing the wall portion 11a is electrically connected to the terminal body 131. Alternatively, the first current collecting member 14 has a disk-shaped structure, which is pressed against the first tab 122 of the electrode assembly 12 and electrically connected, and the other side of the disk-shaped structure is pressed against the connection region 13111 on the first end surface 1311 of the terminal body 131 and electrically connected. The electrical connection can be by contact conduction, bonding by conductive glue, or soldering.

When the connection region 13111 is uneven, the surface of the first current collecting member 14 and the surface of the connection region 13111 may not be in complete contact, a gap may exist between the first current collecting member 14 and the connection region 13111, resulting in poor contact, low adhesion strength during adhesion, a cold joint phenomenon during welding, unstable electrical connection, a small overcurrent area, poor overcurrent capacity, and in severe cases, a connection failure between the first current collecting member 14 and the connection region 13111 may cause a disconnection of an internal circuit of the battery cell 1. By providing the groove 13112 on the first end surface 1311 to separate the connection region 13111 from the first flange 132, stress applied to the first flange 132 is relieved at the groove 13112, stress is prevented from being transmitted to the connection region 13111, the problem that the connection region 13111 deforms under stress is relieved, the connection region 13111 is ensured to be flat, the problem that connection is unstable due to a gap between the connection region 13111 and the first current collecting member 14 is relieved, and overcurrent capacity is improved and service life is prolonged.

According to some embodiments of the present application, as shown in fig. 7 and 8, the groove 13112 is an annular groove disposed around the periphery of the connection region 13111.

As shown in fig. 7 and 8, groove 13112 is a 360 closed ring structure, groove 13112 includes an inner groove wall 13112a at the inner circumference and an outer groove wall 13112b at the outer circumference, and connection region 13111 is formed within the enclosed region of inner groove wall 13112 a. The annular groove can be in the shape of a circular ring or a polygonal ring.

The stress to which the first flange 132 is subjected is transmitted to the outer groove wall 13112b of the groove 13112, and the space between the outer groove wall 13112b and the inner groove wall 13112a can relieve the stress to which the first flange 132 is subjected from the connecting region 13111 connected to the inner groove wall 13112 a. By providing the groove 13112 as a circular groove and using the surrounding area of the groove 13112 as the connection region 13111, stress in either direction is restricted from being transmitted to the connection region 13111, and the connection region 13111 is further ensured to be flat.

In some embodiments, the groove 13112 may not be a 360 ° enclosed annular groove. For example, as shown in fig. 9, the first end surface 1311 is provided with an arc-shaped groove 13112, the groove 13112 extends in the circumferential direction of the terminal body 131, the arc of the groove 13112 is less than 360 °, and the first flange 132 protrudes in the radial direction from the outer circumferential surface of the terminal body 131 at a position corresponding to the groove 13112. As another example, as shown in fig. 10, the first end surface 1311 is provided with a plurality of arc-shaped grooves 13112 (four grooves are taken as an example in fig. 10) distributed at intervals around the circumference of the terminal body 131, each groove 13112 extends along the circumference of the terminal body 131, the first flange 132 includes a plurality of grooves, the plurality of grooves 13112 correspond to the plurality of grooves 13112, and the plurality of grooves 13112 separate the plurality of first flanges 132 from the connection region 13111. In some embodiments, the grooves 13112 may not have a curvature and may be strip-shaped grooves. As shown in fig. 11, the terminal body 131 is a polygonal cylinder, and the groove 13112 extends in the circumferential direction of the terminal body 131 to form a strip-shaped groove.

According to some embodiments of the present application, as shown in fig. 5 and 6, the electrode assembly 12 is a winding type structure, and the first current collecting member 14 covers a winding center hole 124 of the electrode assembly 12.

As previously described, the electrode assembly 12 includes a separator separating the first and second pole pieces and first and second pole pieces of opposite polarity. The first pole piece, the second pole piece and the isolating piece are all of a belt-shaped structure, and the first pole piece, the second pole piece and the isolating piece are wound around the central axis into a whole and form a winding structure. The coiled structure may be a cylindrical structure, a flat structure, or other shaped structure. During winding, the first pole piece, the second pole piece and the separator are wound around a winding needle, and after the winding needle is withdrawn, a winding center hole 124 is formed at the center axis of the electrode assembly 12. Optionally, the first tab 122 is wound around the central axis of the electrode assembly 12 in a plurality of turns, in other words, the first tab 122 includes a plurality of tab layers. After winding, the first tab 122 is substantially cylindrical, and a gap is left between two adjacent tab layers. The present embodiment may treat the first tab 122 to reduce the gap between the tab layers, thereby facilitating the connection of the first tab 122 with the first current collecting member 14. For example, the embodiment of the present application may perform a flattening treatment on the first tab 122 so that the end regions of the first tab 122 away from the body portion 121 are gathered and collected together; the flattening process forms a dense end surface at the end of the first tab 122 remote from the body 121, reducing the gap between the tab layers, facilitating the connection of the first tab 122 to the first current collecting member 14. Alternatively, the embodiment of the application can also fill a conductive material between two adjacent circles of tab layers to reduce the gap between the tab layers. Alternatively, the second tab 123 is wound around the central axis of the electrode assembly 12 in a plurality of turns, and the second tab 123 includes a plurality of turns of tab layers. Illustratively, the second pole piece 123 is also subjected to a flattening process to reduce the gap between the pole piece layers of the second pole piece 123.

The first current collecting member 14 is pressed against the flattened end surface of the first tab 122, one part of the first current collecting member 14 covers the first tab 122, the other part is exposed to the winding central hole 124, and an external welding device emits laser light on the surface of the first current collecting member 14, which is far away from the first tab 122, and the laser light welds the part of the first current collecting member 14, which covers the first tab 122, with the first tab 122.

The portion of the first current collecting member 14 exposed to the winding center hole 124 is pressed against the connection region 13111, and the first current collecting member 14 may be welded to the connection region 13111 through the winding center hole 124 using a welding tool, so that the welding mark is located inside the case 11 to prevent the welding mark from being exposed to the outside, prevent the welding mark from being oxidized and rusted by the external air, and improve the service life of the battery 100.

When the first current collecting member 14 is electrically connected to the connection region 13111 by means of conductive adhesive bonding, pressure may not be indirectly applied to the first current collecting member 14 toward the wall portion 11a through the electrode assembly 12, but pressure may be directly applied to the first current collecting member 14 through the winding center hole 124 using a tool to press the first current collecting member 14 against the connection region 13111, so that the first current collecting member 14 and the connection region 13111 are stably bonded. So as to prevent the electrode assembly 12 from being deformed by force to cause the falling of the active substance layer coated on the pole piece and prevent the electrode assembly 12 from being damaged.

According to some embodiments of the present application, as shown in fig. 6 and 12, the first collecting member 14 includes a collecting body 141 and a protrusion 142, the protrusion 142 protruding from the collecting body 141 toward the electrode terminal 13, the protrusion 142 corresponding to the winding center hole 124 of the electrode assembly 12 in position and serving to connect the connection region 13111, and the collecting body 141 serving to connect the first tab 122.

The current collecting body 141 is a portion covering the first current collecting member 14 covering the first tab 122, and the current collecting body 141 is welded to the first tab 122.

The protrusion 142 protrudes in a direction toward the electrode terminal 13 with respect to the current collector body 141 so as not to cause the first current collecting member 14 not to be in close contact with the connection region 13111 due to structural interference other than the connection region 13111 of the current collector body 141 and the electrode terminal 13. By providing the convex portion 142, the first current collecting member 14 is ensured to be in close contact with the connection region 13111 so as to avoid poor adhesion or poor welding, realize stable overcurrent, and improve the overcurrent capacity and the service life of the battery 100.

According to some embodiments of the present application, as shown in fig. 13 and 14, an outer diameter D1 of the groove is greater than a diameter D3 of the protrusion.

As shown in fig. 7 and 8, groove 13112 is circular and the outer diameter D1 of the groove refers to the diameter of outer wall 13112b of groove 13112. As shown in fig. 12 and 13, the projection 142 is cylindrical, and the diameter D3 of the projection is the diameter of the end face of the cylindrical shape. As shown in fig. 8 and 14, the area of the region surrounded by the outer groove wall 13112b of the groove 13112 is larger than the area of the surface of the projection 142 facing the connection region 13111, and the projection of the projection 142 on the first end surface 1311 falls within the region surrounded by the outer groove wall 13112b in the center axis direction P of the terminal body. Alternatively, the axial center lines of the recess 13112 and the projection 142 are collinear. Alternatively, the axial center lines of the groove 13112 and the projection 142 are both on the central axis of the terminal body 131. Alternatively, the convex portion 142 may be a polygonal column, and the diameter of the outer groove wall 13112b of the groove 13112 is larger than the diameter of a circumscribed circle of the end face of the polygonal column.

When recess 13112 is a polygonal ring, protrusion 142 may be cylindrical or correspondingly configured as a polygonal post: when the projection 142 has a cylindrical shape, the diameter of an inscribed circle of the outer groove wall 13112b of the groove 13112 is larger than the diameter of the end face of the cylindrical shape; when the projection 142 is a polygonal column, the diagonal length of the region surrounded by the outer groove wall 13112b of the groove 13112 is larger than the diagonal length of the end face of the polygonal column. So that the projection of the convex portion 142 on the first end surface 1311 falls within the area surrounded by the outer groove wall 13112 b.

With the above arrangement, the protrusion 142 does not protrude beyond the outer groove wall 13112b in the radial direction R of the terminal body, so that interference between the protrusion 142 and the connection region 13111 is prevented, and a tight connection between the protrusion 142 and the connection region 13111 without a gap is ensured.

According to some embodiments of the present application, as shown in FIG. 14, the inner diameter D2 of the groove is less than the diameter D3 of the protrusion.

Referring to fig. 8, 13, and 14, groove 13112 is an annular ring, and groove inner diameter D2 refers to the diameter of inner wall 13112a of groove 13112. The inner wall 13112a of the recess 13112 encloses a connecting region 13111, the connecting region 13111 is circular in shape, and the inner diameter D2 of the recess is also understood to mean the diameter of the connecting region 13111. The boss 142 is cylindrical and the boss diameter D3 refers to the diameter of the cylinder. The diameter of the connection region 13111 is smaller than the diameter D3 of the cylindrical protrusion such that the area of the surface of the protrusion 142 facing the connection region 13111 is larger than the area enclosed by the inner groove wall 13112a of the groove 13112, that is, the surface of the protrusion 142 facing the connection region 13111 entirely covers the connection region 13111. Alternatively, the convex portion 142 may be provided as a polygonal column, and the diameter of the inner groove wall 13112a of the groove 13112 is smaller than the diameter of an inscribed circle of the end face of the polygonal column.

When the groove 13112 is a polygonal ring, the connection region 13111 is polygonal in shape, and the protrusion 142 may be cylindrical or correspondingly provided as a polygonal column: when the convex portion 142 has a cylindrical shape, the diameter of the circumscribed circle of the connection region 13111 is smaller than the diameter of the end face of the cylindrical shape. When the convex portion 142 is a polygonal column, the diagonal length of the connection region 13111 is smaller than the diagonal length of the end face of the polygonal column.

With the above arrangement, the face of the protrusion 142 facing the connection region 13111 entirely covers the connection region 13111, and the flow area is maximally secured by the connection region 13111.

According to some embodiments of the present application, as shown in fig. 13, the protrusion 142 includes an end wall 1422 and a peripheral wall 1421, the peripheral wall 1421 is disposed around the end wall 1422, the peripheral wall 1421 is connected to the current collecting body 141, the end wall 1422 is connected to the connection region 13111, and the peripheral wall 1421 and the end wall 1422 together define a cavity 1423.

One end of the peripheral wall 1421 is connected to the current collector body 141, the other end of the peripheral wall 1421 protrudes toward the electrode terminal 13 and is connected to the end wall 1422, the end wall 1422 is offset from the current collector body 141, the end wall 1422 is closer to the wall portion 11a than the current collector body 141, and a cavity 1423 is formed on a surface of the first current collecting member 14 facing away from the wall portion 11a, in other words, a surface of the protrusion 142 facing away from the wall portion 11a is provided as the cavity 1423.

The cavity 1423 identifies the position of the projection 142 on the side of the first current collecting member 14 facing away from the wall portion 11a, so as to weld the end wall 1422 and the connection region 13111 from the inside of the wall portion 11 a.

During welding, recess 1423 also serves to position the welding head so as to avoid head deflection and ensure stable connection of tab 142 to attachment region 13111. By providing the recess 1423, the portion of the tab 142 for connecting the connection region 13111 (i.e., the end wall 1422) is reduced in thickness, facilitating penetration welding, as compared to the case where the recess 1423 is not provided on the back surface of the tab 142.

According to some embodiments of the present application, as shown in fig. 13 and 14, the diameter D4 of the cavity is greater than the diameter D5 of the winding center hole.

When the rear surface of the projection 142 is the recess 1423, the projection of the peripheral wall 1421 on the end surface of the electrode assembly 12 is annular, and the diameter D4 of the recess is the inner diameter of the projection of the peripheral wall 1421. The recess 1423 completely covers one end of the winding central hole 124, the welding head passing through the winding central hole 124 without interfering with the current collector body 141, the welding head being able to enter the recess 1423 smoothly to weld the end wall 1422 and the connection zone 13111.

In the case where the diameter of the recess 1423 is constant, the diameter D5 of the winding center hole of the electrode assembly 12 is made smaller than the diameter D4 of the recess by reducing the diameter D5 of the winding center hole, so that the space occupation of the electrode assembly 12 is increased and the energy density of the battery cell 1 is increased.

According to some embodiments of the present application, as shown in fig. 14, a side of the electrode terminal 13 facing the first current collecting member 14 is formed with a slope 133, and the slope 133 is inclined with respect to a plane perpendicular to a central axis direction of the electrode terminal 13 and extends from the outer groove wall 13112b of the groove 13112 in a direction approaching the electrode assembly 12.

The slope 133 is located at a side of the electrode terminal 13 toward the first current collecting member 14, and the slope 133 is radially away from the central axis of the electrode terminal 13 from the outer groove wall 13112b and gradually approaches the electrode assembly 12. The inclined surface 133 is located on the outer periphery of the outer wall 13112b of the groove 13112, in other words, the groove 13112 is located between the connection region 13111 and the inclined surface 133.

By providing the inclined surface 133 at the periphery of the groove 13112 to avoid the first current collecting member 14, the inclined surface 133 guides the first current collecting member 14 to move toward the connection region 13111 when the first current collecting member 14 moves toward the first end surface 1311 to accurately position the first current collecting member 14, ensuring that the first current collecting member 14 is connected to the connection region 13111.

According to some embodiments of the present application, as shown in fig. 7 and 14, the electrode terminal 13 further includes a second flange 134, the second flange 134 protruding from the outer circumferential surface of the terminal body 131 in the radial direction R of the terminal body, the second flange 134 being located outside the wall portion 11a to restrict the electrode terminal 13 from moving in a direction toward the electrode assembly 12.

A second flange 134 is provided at one end of the terminal body 131 extending out of the housing 11, and the second flange 134 is a protrusion provided on the outer peripheral surface of the terminal body 131, that is, the second flange 134 protrudes from the outer peripheral surface of the terminal body 131 in the radial direction R of the terminal body. The second flange 134 directly or indirectly abuts against the outer side of the wall portion 11a to prevent the terminal body 131 from moving to the inner side of the wall portion 11 a. The terminal body 131 and the second flange 134 may be integrally formed, or may be two parts that are formed separately and then connected by welding, bonding, or the like. Optionally, the second flange 134 is integrally formed with the terminal body 131.

By providing the second flange 134, the movement of the electrode terminal 13 along the central axis of the terminal body 131 is restricted by the cooperation of the first flange 132 and the second flange 134, so that the electrode terminal 13 is positioned along the central axis direction P of the terminal body, thereby preventing the electrode terminal 13 from shaking, and further ensuring the stable connection of the electrode terminal 13 and the first current collecting member 14.

According to some embodiments of the present application, as shown in fig. 14, the battery cell 1 further includes an insulating member 16, and the insulating member 16 is disposed between the electrode terminal 13 and the wall portion 11a to insulate and isolate the electrode terminal 13 and the wall portion 11 a.

The insulating member 16 includes a first portion 161, a second portion 162, and a third portion 163 connected in sequence. The first portion 161 is located between the first flange 132 and the inner side surface of the wall portion 11a, and the first flange 132 indirectly abuts against the wall portion 11a through the first portion 161. The second portion 162 surrounds the outer circumference of the terminal body 131, i.e., the second portion 162 is located between the terminal body 131 and the inner wall of the electrode lead-out hole 11 b. The third portion 163 is located between the second flange 134 and the inner side surface of the wall portion 11a, and the second flange 134 indirectly abuts against the wall portion 11a through the third portion 163.

The electrode terminal 13 and the wall portion 11a are isolated by the insulator 16 so as not to charge the wall portion 11a, reducing the risk of short circuit. The insulator 16 also fills the gap between the electrode terminal 13 and the wall portion 11a to alleviate the problem of liquid leakage from the gap between the electrode terminal 13 and the wall portion 11 a.

According to some embodiments of the present application, a side of the second flange 134 facing the wall portion 11a is formed with an annular protrusion 1341, the annular protrusion 1341 is disposed around a central axis of the electrode terminal 13, and the annular protrusion 1341 is configured to press a portion of the insulator 16 between the second flange 134 and the wall portion 11 a.

In other words, at the annular projection 1341, the distance of the second flange 134 from the outer side surface of the wall portion 11a is reduced to further press the third portion 163 of the compression insulator 16 toward the outer side surface of the wall portion 11a, so that an annular seal region is formed between the second flange 134 and the wall portion 11a to further alleviate the problem of liquid leakage from the gap between the electrode terminal 13 and the wall portion 11 a.

According to some embodiments of the present application, as shown in fig. 14, a projection of the first flange 132 on the second flange 134 in the thickness direction of the wall portion 11a covers the annular protrusion 1341.

The distance from the edge of the first flange 132 to the central axis of the terminal body 131 is greater than the distance from the annular protrusion 1341 to the central axis of the terminal body 131. The annular projection 1341 presses the wall portion 11a through the insulator 16 on the outer side of the wall portion 11a, and the first flange 132 supports a portion of the wall portion 11a pressed by the annular projection 1341 on the inner side so as not to deform the wall portion 11a under pressure. Under the cooperation of the wall portion 11a and the annular protrusion 1341, the insulating member 16 is securely pressed, and a gap between the electrode terminal 13 and the wall portion 11a is eliminated, thereby improving the sealing effect.

According to some embodiments of the present application, as shown in fig. 4 and 5, the housing 11 includes a casing 111 and an end cover 112, the casing 111 includes a side wall 1111 and a bottom wall 1112, the side wall 1111 is enclosed around the bottom wall 1112, one end of the side wall 1111 is connected to the bottom wall 1112, the other end of the side wall 1111 encloses an opening opposite to the bottom wall 1112, the end cover 112 covers the opening, and the wall portion 11a is the bottom wall 1112 or the end cover 112.

In the drawings of the present application, an embodiment in which the wall portion 11a is the bottom wall 1112 is shown, but in other embodiments, the wall portion 11a may be the end cap 112, the end cap 112 is provided with the electrode lead-out hole 11b, and the electrode terminal 13 is inserted into the electrode lead-out hole 11b of the end cap 112. That is, one of the bottom wall 1112 and the end cap 112 provides the electrode terminal 13.

According to some embodiments of the present application, as shown in fig. 5 and 6, the electrode terminal 13 is insulated from the wall part 11a, and one end of the electrode assembly 12, which is far from the wall part 11a, is formed with a second tab 123, the second tab 123 having an opposite polarity to the first tab 122; the battery cell 1 further includes a second current collecting member 15, and the second current collecting member 15 is used to electrically connect the second pole piece 123 and the wall portion 11 a.

The wall 11a is a bottom wall 1112, and the electrode terminal 13 is insulated from the bottom wall 1112 and electrically connected to the first tab 122 of the electrode assembly 12 via the first current collecting member 14. The end cap 112 is located at an end of the side wall 1111 remote from the bottom wall 1112, and the end cap 112 is attached to the side wall 1111 to close the opening. The second current collecting member 15 is located between the electrode assembly 12 and the end cap 112.

The second current collecting member 15 for electrically connecting the second pole lug 123 and the wall portion 11a means that the second current collecting member 15 is electrically connected to the second pole lug 123 while the second current collecting member 15 is electrically connected to the wall portion 11a so that the second pole lug 123 and the wall portion 11a are charged in the same polarity.

Alternatively, the second current collecting member 15 is pressed against the flattened end face of the second tab 123, and an external welding device emits a laser on the surface of the second current collecting member 15 facing away from the second tab 123, and the laser welds the second current collecting member 15 to the second tab 123.

Alternatively, the second current collecting member 15 is directly electrically connected to the case 111 to lead out electric power to the wall portion 11 a.

Alternatively, the second current collecting member 15 may also be electrically connected to the case 111 indirectly through the end cap 112. As shown in fig. 5, the second current collecting member 15 is electrically connected to the end cover 112, and the end cover 112 is electrically connected to the side wall 1111. For example, the second current collecting member 15 is welded to the middle of the end cover 112, and the outer circumference of the end cover 112 is welded to the side wall 1111. For another example, the end cap 112 is provided with the electrode terminal 13, the second current collecting member 15 is welded to the electrode terminal 13, and the outer circumference of the end cap 112 is welded to the side wall 1111.

With the above arrangement, the wall 11a and the electrode terminal 13 have opposite polarities, and the wall 11a and the electrode terminal 13 can be respectively used as the positive output electrode and the negative output electrode of the battery cell 1, so that the bus member connects the positive output electrode and the negative output electrode at the same end of the battery cell 1, and assembly is facilitated. Alternatively, the pressure relief mechanism may be disposed at an end away from the wall portion 11a, and the pressure relief mechanism is away from the bus member, so as to prevent the bus member from being damaged by impact when the pressure relief mechanism is released.

In a second aspect, the embodiment of the present application provides a battery 100, and as shown in fig. 2 and fig. 3, the battery 100 includes the aforementioned battery cell 1.

In a third aspect, an embodiment of the present application provides an electric device, as shown in fig. 1, the electric device may be selected as a vehicle, and the vehicle includes the foregoing battery 100.

In a fourth aspect, embodiments of the present application provide a method for manufacturing a battery cell 1, as shown in fig. 5, 6 and 15, the method includes:

s101, providing an electrode assembly 12, wherein a first tab 122 is formed at one end of the electrode assembly 12.

S102, providing a case 111 and an electrode terminal 13, wherein the case 111 includes a bottom wall 1112 and a side wall 1111, the side wall 1111 is enclosed around the bottom wall 1112, one end of the side wall 1111 is connected to the bottom wall 1112, the other end of the side wall 1111 is enclosed to form an opening opposite to the bottom wall 1112, the bottom wall 1112 is provided with an electrode lead-out hole 11b, the electrode terminal 13 includes a terminal body 131 and a first flange 132, the terminal body 131 is inserted through the electrode lead-out hole 11b, the first flange 132 protrudes from the outer circumferential surface of the terminal body 131 in the radial direction R of the terminal body, the first flange 132 is located inside the bottom wall 1112 to limit the movement of the electrode terminal 13 in the direction away from the electrode assembly 12, the terminal body 131 has a first end surface 1311 facing the inside of the case 111, the first end surface 1311 is provided with a groove 13112 and a connection region 13111 for connection with the first current collecting member 14, and the groove 13112 is located between the connection region 13111 and the first flange 132.

And S103, providing a first current collecting member 14.

And S104, connecting the first current collecting member 14 to the first tab 122.

S105, the electrode assembly 12 and the first current collecting member 14 are put into the case 111 with the first current collecting member 14 positioned between the bottom wall 1112 and the electrode assembly 12.

And S106, connecting the first current collecting member 14 to the connection region 13111.

S107, providing an end cover 112, and covering the end cover 112 on the opening of the shell 111.

In addition, for the structure of the battery cell 1 manufactured by the method for manufacturing the battery cell 1, reference may be made to the battery cell 1 provided in each of the above embodiments.

When the battery cell 1 is assembled based on the above-described manufacturing method of the battery cell 1, it is not necessary to sequentially perform the above-described steps, that is, the steps may be performed in the order mentioned in the embodiments, may be performed in an order different from the order mentioned in the embodiments, or may be performed several steps at the same time. For example, steps S101 and S102 may be executed simultaneously without being performed sequentially.

According to some embodiments of the present application, the step of coupling the first current collecting member 14 to the first tab 122 is completed before the step of placing the electrode assembly 12 into the case 111.

That is, step S104 is completed before step S105, so that after the first current collecting member 14 and the electrode assembly 12 are connected into a whole, the electrode assembly 12 and the first current collecting member 14 are put into the case 111 together, thereby ensuring that the first current collecting member 14 and the first tab 122 are connected stably and improving the overcurrent capacity.

According to some embodiments of the present application, the step S106 of connecting the first current collecting member 14 to the connection region 13111 includes: as shown in fig. 16, the first current collecting member 14 and the connection region 13111 are welded by passing the welding unit 4071 from the opening into the case 111 and through the winding center hole 124 of the electrode assembly 12.

In the above technical solution, the welding seal between the first current collecting member 14 and the electrode terminal 13 is located inside the battery cell 1, and the welding seal does not contact with the outside air, is not easily oxidized and rusted, and prolongs the service life of the battery 100.

In a fifth aspect, the present embodiment provides a device 400 for preparing a battery cell 1, as shown in fig. 17, including:

a first providing device 401 for providing an electrode assembly 12, one end of the electrode assembly 12 being formed with a first tab 122;

the second providing device 402 is used for providing the housing 111 and the electrode terminal 13, the housing 111 includes a bottom wall 1112 and a side wall 1111, the side wall 1111 is surrounded around the bottom wall 1112, one end of the side wall 1111 is connected with the bottom wall 1112, the other end of the side wall 1111 is surrounded to form an opening opposite to the bottom wall 1112, the bottom wall 1112 is provided with an electrode lead-out hole 11b, the electrode terminal 13 includes a terminal body 131 and a first flange 132, the terminal body 131 is arranged through the electrode lead-out hole 11b, the first flange 132 protrudes out of the outer circumferential surface of the terminal body 131 along the radial direction R of the terminal body, the first flange 132 is positioned at the inner side of the bottom wall 1112, to restrict the electrode terminal 13 from moving in a direction away from the electrode assembly 12, the terminal body 131 has a first end surface 1311 facing the inside of the case 111, the first end surface 1311 is provided with a groove 13112 and a connection region 13111 for connection with the first current collecting member 14, the groove 13112 is located between the connection region 13111 and the first flange 132;

a third supply device 403 for supplying the first current collecting member 14;

a fourth providing means 404 for providing the end cap 112;

a first assembly device 405 for connecting the first current collecting member 14 to the first tab 122;

a second assembling means 406 for putting the electrode assembly 12 and the first current collecting member 14 into the case 111 with the first current collecting member 14 between the wall portion 11a and the electrode assembly 12;

a third assembling device 407 for connecting the first current collecting member 14 to the connection region 13111;

and a fourth assembling device 408 for covering the end cap 112 on the opening of the housing 111.

The first supply device 401, the second supply device 402, the third supply device 403, the fourth supply device 404, the first assembly device 405, the second assembly device 406, the third assembly device 407, and the fourth assembly device 408 may be disposed on the same production line, the first supply device 401, the second supply device 402, the third supply device 403, and the fourth supply device 404 may be conveying devices on the production line, and the first assembly device 405, the second assembly device 406, the third assembly device 407, and the fourth assembly device 408 may assemble the conveyed components to form the battery cell 1.

According to some embodiments of the present application, the third assembling device 407 is used to weld the first current collecting member 14 to the connection region 13111, and the third assembling device 407 includes a welding unit 4071, and the welding unit 4071 is used to enter the case 111 and pass through the winding center hole 124 of the electrode assembly 12 to weld the first current collecting member 14 and the connection region 13111.

Alternatively, the welding unit 4071 is an ultrasonic horn that passes through the winding center hole 124 of the electrode assembly 12 and acts on the first current collecting member 14 to weld the first current collecting member 14 to the connection region 13111.

For the structure of the battery cell 1 manufactured by the manufacturing apparatus 400, reference may be made to the battery cell 1 provided in each of the above embodiments.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

In a sixth aspect, an embodiment of the present application provides an assembling method of the housing 111 and the electrode terminal 13, as shown in fig. 18, the assembling method includes:

s201, as shown in fig. 19, providing a housing 111, where the housing 111 includes a bottom wall 1112 and a side wall 1111, the side wall 1111 is surrounded around the bottom wall 1112, one end of the side wall 1111 is connected to the bottom wall 1112, the other end of the side wall 1111 is surrounded to form an opening opposite to the bottom wall 1112, and the bottom wall 1112 is provided with an electrode lead-out hole 11 b;

s202, as shown in fig. 19, providing an electrode terminal 13, where the electrode terminal 13 includes a terminal body 131 and a first flange 132, the terminal body 131 has a first end surface 1311, the first flange 132 protrudes from the first end surface 1311 along a central axis direction P of the terminal body, the first flange 132 is disposed around the first end surface 1311, the first end surface 1311 is provided with a groove 13112 and a connection region 13111, and the groove 13112 is located between the connection region 13111 and the first flange 132;

s203, as shown in fig. 20, the electrode terminal 13 is inserted into the electrode lead-out hole 11b so that the first flange 132 is positioned inside the bottom wall 1112, and as shown in fig. 20 and 21, the first flange 132 is bent so that the first flange 132 protrudes from the outer peripheral surface of the terminal body 131 in the radial direction of the electrode terminal 13, so that the first flange 132 restricts the movement of the electrode terminal 13 to the outside of the bottom wall 1112.

As shown in fig. 20, before assembly, the first flange 132 protrudes from the first end surface 1311 in the central axis direction P of the terminal body, so that the end of the electrode terminal 13 having the first flange 132 can pass through the electrode lead-out hole 11b and is located inside the bottom wall 1112.

As shown in fig. 21, when assembling, the first flange 132 is turned outward so that the first flange 132 protrudes from the outer circumferential surface of the terminal body 131 in the radial direction R of the terminal body, so that the first flange 132 restricts the electrode terminal 13 from moving outward of the bottom wall 1112.

The mounting of the electrode terminal 13 to the case 111 is achieved by this assembly method, and the space in the vicinity of the connection region 13111 is also increased to facilitate the connection of the first current collecting member 14. Since the first end surface 1311 of the terminal body 131 is provided with the groove 13112, the first flange 132 releases stress at the groove 13112 in the process of bending the first flange 132 so as not to transmit the stress to the connection region 13111, and flatness of the connection region 13111 is ensured. In addition, in the process of bending first flange 132, first flange 132 is pressed, the material flows to the periphery, and since groove 13112 is arranged between first flange 132 and connecting region 13111, the material flowing due to pressing is absorbed by groove 13112, so that the material is prevented from entering connecting region 13111, and connecting region 13111 is ensured to be flat and not deformed.

Specifically, in step S203, the first flange 132 is bent so as to be caulked in the central axis direction P of the terminal body so that the electrode terminal 13 is riveted to the bottom wall 1112.

In a seventh aspect, an embodiment of the present application provides an assembly apparatus 500 of the housing 111 and the electrode terminal 13, and as shown in fig. 19 to fig. 22, the assembly apparatus 500 includes:

a fifth providing device 501, configured to provide the casing 111, where the casing 111 includes a bottom wall 1112 and a side wall 1111, the side wall 1111 is surrounded around the bottom wall 1112, one end of the side wall 1111 is connected to the bottom wall 1112, the other end of the side wall 1111 is surrounded to form an opening opposite to the bottom wall 1112, and the bottom wall 1112 is provided with an electrode lead-out hole 11 b;

a sixth providing device 502 for providing the electrode terminal 13, the electrode terminal 13 including a terminal body 131 and a first flange 132, the terminal body 131 having a first end surface 1311, the first flange 132 protruding from the first end surface 1311 along a central axis direction P of the terminal body, the first flange 132 being disposed around the first end surface 1311, the first end surface 1311 being provided with a groove 13112 and a connection region 13111, the groove 13112 being located between the connection region 13111 and the first flange 132;

the fifth assembling device 503 is configured to insert the electrode terminal 13 into the electrode lead-out hole 11b, position the first flange 132 inside the wall portion 11a, bend the first flange 132 such that the first flange 132 protrudes from the outer circumferential surface of the terminal body 131 in the radial direction of the electrode terminal 13, and restrict the electrode terminal 13 from moving to the outside of the wall portion 11a by the first flange 132.

Specifically, the fifth assembling device 503 includes a caulking mechanism 5031, as shown in fig. 20, the caulking mechanism 5031 is configured to enter the inside of the housing 111 from the opening of the housing 111 and caulk the first flange 132 in the central axis direction P of the terminal body to bend the first flange 132 so that the electrode terminal 13 is riveted to the bottom wall 1112.

According to some embodiments of the present application, referring to fig. 5 to 6 and 14, embodiments of the present application provide a battery cell 1, the battery cell 1 including a case 11, an electrode terminal 13, an electrode assembly 12, a first current collecting member 14, and a second current collecting member 15.

The housing 11 includes a case 111 and an end cap 112, the case 111 includes a bottom wall and a side wall, the side wall 1111 surrounds the bottom wall, one end of the side wall 1111 is connected to the bottom wall 1112, the other end of the side wall 1111 surrounds an opening opposite to the bottom wall 1112, the end cap 112 covers the opening, and the bottom wall 1112 is provided with an electrode lead-out hole 11b for mounting the electrode terminal 13. The electrode terminal 13 includes a terminal body 131, a first flange 132 and a second flange 134, the first flange 132 and the second flange 134 respectively protrude from the outer circumferential surface of the terminal body 131 in the radial direction, the electrode terminal 13 is inserted into the electrode lead-out hole 11b, the first flange 132 is located inside the bottom wall 1112, the first flange 132 is used for limiting the terminal body 131 from moving to the outside of the bottom wall 1112, the second flange 134 is located outside the bottom wall 1112, and the second flange 134 is used for limiting the terminal body 131 from moving to the inside of the bottom wall 1112. Wherein, the end face of the terminal body 131 facing the electrode assembly 12 is a first end face 1311, the first end face 1311 is formed with a groove 13112 and a connection region 13111, the groove 13112 is provided in an annular groove between the connection region 13111 and the first flange 132, and the groove 13112 is used to allow the first flange 132 to release stress and deformation to limit the stress applied to the first flange 132 from being conducted to the connection region 13111, and to ensure the flatness of the connection region 13111. An insulating member 16 is provided between the electrode terminal 13 and the bottom wall 1112, and the insulating member 16 serves to insulate and isolate the electrode terminal 13 from the bottom wall 1112. An annular protrusion 1341 is formed on a side of the second flange 134 facing the bottom wall 1112, the annular protrusion 1341 presses the insulator 16 on the outer side of the bottom wall 1112 to form an annular sealing area to seal the housing 11, a projection of the first flange 132 on the second flange 134 covers the annular protrusion 1341, and the first flange 132 supports the bottom wall 1112 on the inner side of the bottom wall 1112 to prevent the bottom wall 1112 from being deformed under pressure, so as to ensure the sealing effect.

The first current collecting member 14, the second current collecting member 15 and the electrode assembly 12 are located in the case 11, the electrode assembly 12 is in a winding structure, a first tab 122 is disposed at one end of the electrode assembly 12 facing the bottom wall 1112, a second tab 123 is disposed at one end of the electrode assembly 12 facing the end cap 112, the first current collecting member 14 is used for connecting the first tab 122 of the electrode assembly 12, and the second current collecting member 15 is used for connecting the second tab 123 of the electrode assembly 12. The first current collecting member 14 includes a current collecting body 141 and a tab 142, the current collecting body 141 is connected to the first tab 122, the tab 142 includes an end wall 1422 and a peripheral wall 1421, the peripheral wall 1421 is surrounded by the end wall 1422, the peripheral wall 1421 and the end wall 1422 together define a cavity 1423, the peripheral wall 1421 is connected to the current collecting body 141 so that the end wall 1422 protrudes toward the electrode terminal 13 with respect to the current collecting body 141, and the end wall 1422 is connected to the connection region 13111. The protrusion 142 and the groove 13112 satisfy: the inner diameter D2 of the groove < the diameter D3 of the convex part < the outer diameter D1 of the groove. Meanwhile, the diameter D4 of the recess is larger than the diameter D5 of the winding center hole of the electrode assembly 12. The second current collecting member 15 is connected to the second tab 123, the second current collecting member 15 is provided with a through hole 151 corresponding to the winding center hole 124 of the electrode assembly 12, and a side of the second current collecting member 15 facing away from the electrode assembly 12 is connected to the end cap 112 to electrically charge the side wall 1111 and the bottom wall 1112.

With the above arrangement, the polarity of the electrode terminal 13 and the bottom wall 1112 is opposite, and the electrode terminal 13 and the bottom wall 1112 can be respectively used as a positive output electrode and a negative output electrode of the battery cell 1, so that the bus bar member can be connected at the same end of the battery cell 1.

The embodiment of the present application further provides a method for preparing the battery cell 1, and referring to fig. 5, fig. 6, and fig. 15, the method for preparing the battery cell 1 includes: providing an electrode assembly 12, providing an assembled case 111 and electrode terminals 13 (see fig. 21), providing a first current collecting member 14, providing a second current collecting member 15, providing an end cap 112; attaching the first current collecting member 14 to the first tab 122, attaching the second current collecting member 15 to the second tab 123, and then integrally placing the electrode assembly 12, the first current collecting member 14, and the second current collecting member 15 into the case 11 with the first current collecting member 14 positioned between the bottom wall 1112 and the electrode assembly 12; a welding unit (e.g., an ultrasonic welding horn) is introduced into the case 111 from the opening, sequentially passes through the through-hole 151 on the second current collecting member 15, the winding center hole 124 of the electrode assembly 12 into the recess 1423, and acts on the end wall 1422 to weld the end wall 1422 to the connection region 13111, to electrically connect the first current collecting member 14 with the electrode terminal 13, and to cover the opening with the end cap 112.

Among them, the method of assembling the case 111 and the electrode terminal 13, referring to fig. 18 to 21, includes: providing a housing 111, as shown in fig. 19, the housing 111 includes a bottom wall 1112 and a side wall 1111, the side wall 1111 is surrounded around the bottom wall 1112, one end of the side wall 1111 is connected to the bottom wall 1112, the other end of the side wall 1111 is surrounded as an opening opposite to the bottom wall 1112, the bottom wall 1112 is provided with an electrode lead-out hole 11 b; providing an electrode terminal 13, as shown in fig. 19, the electrode terminal 13 including a terminal body 131 and a first flange 132, the terminal body 131 having a first end surface 1311, the first flange 132 protruding from the first end surface 1311 in a central axis direction P of the terminal body, the first flange 132 being disposed around the first end surface 1311, the first end surface 1311 being provided with a groove 13112 and a connection region 13111, the groove 13112 being located between the connection region 13111 and the first flange 132; as shown in fig. 20, the electrode terminal 13 is inserted into the electrode lead-out hole 11b such that the first flange 132 is positioned inside the wall portion 11a, and as shown in fig. 21, the first flange 132 is bent such that the first flange 132 protrudes from the outer circumferential surface of the terminal body 131 in the radial direction of the electrode terminal 13, so that the first flange 132 restricts the movement of the electrode terminal 13 to the outside of the wall portion 11 a.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery cell, comprising:

a housing including a wall portion, the wall portion having an electrode lead-out hole;

an electrode assembly disposed inside the case, the electrode assembly having a first tab formed at an end facing the wall portion;

the electrode terminal comprises a terminal body and a first flange, the terminal body is arranged in the electrode leading-out hole in a penetrating mode, the first flange protrudes out of the outer peripheral surface of the terminal body along the radial direction of the terminal body, and the first flange is located on the inner side of the wall portion so as to limit the electrode terminal to move along the direction departing from the electrode assembly;

a first current collecting member between the wall and the electrode assembly for connecting the electrode terminal and the first tab;

the terminal body is provided with a first end face facing the first current collecting member, the first end face is provided with a groove and a connecting area used for being connected with the first current collecting member, and the groove is located between the connecting area and the first flange.

2. The battery cell as recited in claim 1 wherein the recess is an annular groove disposed around the periphery of the connection region.

3. The battery cell according to claim 2, wherein the electrode assembly is a wound structure, and the first current collecting member covers a wound center hole of the electrode assembly.

4. The battery cell as recited in claim 3, wherein the first current collecting member includes a current collecting body and a protrusion protruding from the current collecting body in a direction toward the electrode terminal, the protrusion corresponding to a winding center hole of the electrode assembly and serving to connect the connection region, and the current collecting body serving to connect the first tab.

5. The battery cell as recited in claim 4 wherein the groove has an outer diameter greater than a diameter of the protrusion.

6. The battery cell as recited in claim 4 wherein the inner diameter of the groove is less than the diameter of the protrusion.

7. The battery cell as recited in claim 4 wherein the protrusion includes an end wall and a peripheral wall, the peripheral wall being disposed around the end wall, the peripheral wall being connected to the current collector body, the end wall being connected to the connection region, the peripheral wall and the end wall together defining a cavity.

8. The cell defined in claim 7, wherein the diameter of the cavity is greater than the diameter of the winding center bore.

9. The battery cell according to any one of claims 1 to 8, wherein a side of the electrode terminal facing the first current collecting member is formed with a slope inclined with respect to a plane perpendicular to a direction of a central axis of the electrode terminal and extending from an outer groove wall of the groove in a direction approaching the electrode assembly.

10. The battery cell as recited in claim 1, wherein the electrode terminal further comprises a second flange protruding from an outer circumferential surface of the terminal body in a radial direction of the terminal body, the second flange being located outside the wall portion to restrict movement of the electrode terminal in a direction toward the electrode assembly.

11. The battery cell according to claim 10, further comprising an insulating member disposed between the electrode terminal and the wall portion to insulate and separate the electrode terminal and the wall portion.

12. The battery cell according to claim 11, wherein a side of the second flange facing the wall portion is formed with an annular projection disposed around a central axis of the electrode terminal, the annular projection being configured to press a portion of the insulator between the second flange and the wall portion.

13. The battery cell as recited in claim 12, wherein a projection of the first flange on the second flange covers the annular protrusion in a thickness direction of the wall portion.

14. The battery cell as recited in claim 1 wherein the housing comprises a casing and an end cap, the casing comprising a bottom wall and a side wall, the side wall being disposed around the bottom wall, one end of the side wall being connected to the bottom wall, the other end of the side wall defining an opening opposite the bottom wall, the end cap covering the opening, the wall being the bottom wall or the end cap.

15. The battery cell as recited in claim 1, wherein the electrode terminal is insulated from the wall portion, and wherein a second tab is formed at an end of the electrode assembly remote from the wall portion, the second tab being opposite in polarity to the first tab;

the battery cell also includes a second current collecting member for electrically connecting the second tab and the wall portion.

16. A battery comprising the battery cell of any one of claims 1-15.

17. An electrical device comprising the battery of claim 16.