CN217334238U

CN217334238U - Shell, battery monomer, battery and consumer

Info

Publication number: CN217334238U
Application number: CN202221473696.6U
Authority: CN
Inventors: 吉星; 汪洋
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2022-06-14
Filing date: 2022-06-14
Publication date: 2022-08-30
Anticipated expiration: 2032-06-14
Also published as: WO2023240746A1; CN118176619A

Abstract

The application provides a shell, battery monomer, battery and consumer relates to battery technical field. The case is used for accommodating the electrode assembly, and the case includes: an end cap and a housing; the end cover is provided with a pressure relief part, and the pressure relief part is provided with a pressure relief groove; a disassembly groove is formed in the shell; the ratio of the depth of the disassembly groove to the thickness of the shell is L1, the ratio of the depth of the pressure relief groove to the thickness of the pressure relief part is L2, and L1 is less than L2. Due to the arrangement of the disassembling groove, when external force is provided, the shell can be separated at the disassembling groove, so that the disassembling is more convenient; simultaneously, the groove depth proportion of disassembling the groove is less than the groove depth proportion of the pressure relief groove of pressure relief portion, and when the pressure or the temperature in shell inside reached the threshold value, the shell will split along the pressure relief groove, realizes the pressure release, can make to disassemble the groove and do not influence the free normal use of battery.

Description

Shell, battery monomer, battery and consumer

Technical Field

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

Background

Lithium ion batteries are widely used due to their excellent electrochemical properties, and particularly, with the development of new energy automobile industry in recent years, more and more lithium ion batteries are widely used in electric automobiles. However, the service life of a general lithium ion battery is generally 5-8 years, and the problem of recycling the lithium ion battery is particularly important along with the end of the service life of the lithium ion battery.

SUMMERY OF THE UTILITY MODEL

The application provides a shell, battery monomer, battery and consumer, can make the recovery of battery more convenient.

In a first aspect, an embodiment of the present application provides a case for accommodating an electrode assembly, the case including: an end cap and a housing; the end cover is provided with a pressure relief part, and the pressure relief part is provided with a pressure relief groove; the shell is provided with a disassembling groove; the ratio of the depth of the disassembly groove to the thickness of the shell is L1, the ratio of the depth of the pressure relief groove to the thickness of the pressure relief part is L2, and L1 is less than L2.

In the technical scheme, due to the arrangement of the disassembling groove, when external force is provided, the shell can be separated at the disassembling groove, so that the disassembling is more convenient, and the recovery of the battery is more convenient; simultaneously, the groove depth proportion of disassembling the groove is less than the groove depth proportion of the pressure relief groove of pressure relief portion, and when the pressure or the temperature in the shell reached the threshold value, the shell will split along the pressure relief groove, realizes the pressure release, can make to disassemble the groove and do not influence the free normal use of battery.

In some embodiments, the end cap covers the opening of the shell and is welded with the edge of the opening of the shell, and the minimum distance D1 between the dismantling groove and the end cap is more than 0.3 cm. The end cover can produce the welding heat effect with the casing welding, in this application, disassembles the minimum distance D1 > 0.3cm of groove and end cover, makes the region of disassembling the groove setting avoid the region of welding heat effect to can make the bulk strength of shell higher.

In some embodiments, the housing includes a peripheral wall and the un-mating groove includes a first annular groove circumferentially disposed in the peripheral wall. An external force may be applied along the first annular groove to split the case along the first annular groove, thereby separating the case into two parts so that the electrode assembly inside the case can be taken out to recycle the battery.

In some embodiments, the angle between the plane of the first annular groove and the plane of the opening of the peripheral wall is less than 5 °. The surface that first ring channel place is parallel with the face at the opening place of perisporium basically, can make the length of ring channel shorter when forming the ring channel so that disassemble to can guarantee the intensity of shell to a certain extent.

In some embodiments, the disassembly groove further comprises a second annular groove circumferentially disposed in the peripheral wall, the first annular groove intersecting the second annular groove. When the shell is disassembled, external force can be applied to the intersection point of the first annular groove and the second annular groove, and the disassembly is carried out by taking the intersection point as a starting point, so that the labor is saved; meanwhile, when the external force is continuously applied for disassembly, the external force can be applied along the area between the two annular grooves, so that the disassembly is more convenient, the scratch on hands is avoided, and the disassembly is more convenient.

In some embodiments, the end cap is further provided with a positive electrode terminal and a negative electrode terminal, and the distance between the intersection of the first annular groove and the second annular groove and the positive electrode terminal is smaller than the distance between the intersection and the negative electrode terminal. When external force is applied to disassemble, the intersection point cracks, and the shell at the edge of the intersection point can move inwards, so that the shell can be contacted with the lug; the intersection point is arranged at a position close to the positive electrode side, so that the contact between the shell and the negative electrode can be avoided, and the safety performance of the battery during disassembly is improved.

In some embodiments, the disassembly groove further comprises a second annular groove circumferentially disposed in the peripheral wall, the second annular groove being located on a side of the first annular groove remote from the end cap. When the shell is disassembled, external force is directly applied to the area between the two annular grooves, so that the disassembly is more convenient, the scratch on hands is avoided, and the disassembly is more convenient.

In some embodiments, the angle between the plane of the second annular groove and the plane of the opening of the peripheral wall is less than 5 °. The face that the second annular groove place is parallel with the face that the opening of perisporium was located basically, can form the annular groove so that when disassembling, make the length of annular groove shorter to can guarantee the intensity of shell to a certain extent.

In some embodiments, the dismantling groove further comprises an auxiliary groove disposed at the peripheral wall, and both ends of the auxiliary groove are respectively connected to the first annular groove and the second annular groove. When the shell is disassembled, external force can be applied to the intersection of the first annular groove, the second annular groove and the auxiliary groove, and the disassembly is carried out by taking the external force as a starting point, so that the labor is saved; meanwhile, when the external force is continuously applied for disassembly, the external force can be applied along the area between the two annular grooves, so that the disassembly is more convenient, the scratch on hands is avoided, and the disassembly is more convenient.

In some embodiments, the junction of the auxiliary groove and the first annular groove is a first junction point, the junction of the auxiliary groove and the second annular groove is a second junction point, and the distance between the first junction point and the second junction point is the minimum distance between the first annular groove and the second annular groove. The length of auxiliary tank is shorter relatively, when can realizing conveniently dismantling, can also guarantee the intensity of shell to a certain extent.

In some embodiments, the auxiliary groove is a line-segment groove, and the extending direction of the line-segment groove forms an included angle of 85-90 degrees with the surface of the peripheral wall where the opening is located. The extending direction of the auxiliary groove is basically vertical to the surface of the opening of the peripheral wall, so that the auxiliary groove can be formed for disassembly, and meanwhile, the length of the auxiliary groove is shorter, and the strength of the shell can be ensured to a certain extent.

In some embodiments, the end cap is further provided with a positive electrode terminal and a negative electrode terminal, and the distance between the auxiliary groove and the positive electrode terminal is smaller than that between the auxiliary groove and the negative electrode terminal. When external force is applied to disassemble, the auxiliary groove is cracked, and a shell at the edge of the auxiliary groove can move inwards, so that the auxiliary groove can be contacted with the lug; the auxiliary groove is arranged at a position close to the positive electrode side, so that the contact between the shell and the negative electrode can be avoided, and the safety performance of the battery during disassembly is improved.

In some embodiments, the peripheral wall is square, the peripheral wall includes two large faces with larger area and two side faces with smaller area, the two large faces are opposite to each other, and the auxiliary groove is arranged on the large faces. The auxiliary groove is more convenient to set, and meanwhile, when external force is applied to the edge of the auxiliary groove and the position between the two annular grooves, the auxiliary groove is more convenient to set.

In some embodiments, the minimum distance between the first annular groove and the second annular groove is no less than 1.5 cm. Application of external forces may be facilitated, for example: when the position between the first annular groove and the second annular groove is pressed by hands, the hands are not scratched.

In some embodiments, the housing further comprises a bottom wall. The bottom wall is located at one end of the peripheral wall and is integrally formed with the peripheral wall, and the peripheral wall forms an opening at the end opposite to the bottom wall. The strength of the housing can be made high.

In some embodiments, the break-down groove is a break-down score. The setting of disassembling the nick is more convenient, and the width of nick is less, and is less to the intensity of casing and influence such as pleasing to the eye.

In some embodiments, the un-mating grooves are concave from the outside inward. The position of the disassembling groove can be conveniently observed, so that when the shell needs to be disassembled, the position of the disassembling groove is easily found and disassembled.

In a second aspect, an embodiment of the present application provides a battery cell, including: the case and the electrode assembly as provided in the first aspect; the electrode assembly is placed in the shell, and the end cover is covered on the opening of the shell.

Among the above-mentioned technical scheme, can make things convenient for the disassembling of casing to disassemble out electrode subassembly from the casing, thereby be convenient for retrieve the battery.

In some embodiments, the minimum distance of the disassembly groove from the main portion of the electrode assembly is greater than 0. If the case is disassembled at the disassembly groove by applying an external force, a part of the case may move toward the inside of the case, and the position of the disassembly groove is limited within the above range, so that the part moving toward the inside of the case may be prevented from piercing the main body of the electrode assembly, so as to recover the electrode assembly.

In a third aspect, an embodiment of the present application provides a battery, which includes the battery cell provided in the second aspect and a case; the box is used for holding the battery monomer.

In a fourth aspect, an embodiment of the present application provides an electric device, including the battery provided in the third aspect, where the battery is used to provide electric energy.

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 schematic illustration of a vehicle according to some embodiments of the present application;

fig. 2 is an exploded view of a battery provided in accordance with some embodiments of the present application;

fig. 3 is an exploded schematic view of a battery cell according to some embodiments of the present disclosure;

FIG. 4 is an exploded schematic view of an end cap assembly provided in accordance with some embodiments of the present application;

FIG. 5 is a schematic structural view of a housing provided in accordance with some embodiments of the present application;

FIG. 6 is a cross-sectional view taken along A-A of FIG. 5;

FIG. 7 is an enlarged view at B in FIG. 6;

FIG. 8 is a first schematic view of a housing provided in accordance with some embodiments of the present application;

FIG. 9 is a second schematic view of a housing provided by some embodiments of the present application;

FIG. 10 is a third schematic view of a housing provided in accordance with some embodiments of the present application;

FIG. 11 is a fourth schematic view of a housing provided by some embodiments of the present application;

FIG. 12 is a fifth schematic view of a housing provided in accordance with some embodiments of the present application;

FIG. 13 is a sixth schematic view of a housing provided in accordance with some embodiments of the present application;

fig. 14 is a seventh schematic view of a housing provided in accordance with some embodiments of the present application.

An icon: 1000-a vehicle; 100-a battery; 200-a controller; 300-a motor; 10-a box body; 20-a battery cell; 11-a first part; 12-a second part; 21-a housing; 22-an electrode assembly; 23-an end cap assembly; 212-a housing; 231-end caps; 232-pressure relief portion; 233-an insulator; 221-a body portion; 222-positive electrode tab; 223-negative pole tab; 234-positive electrode terminal; 235-negative electrode terminal; 2321-pressure relief groove; 2121-disassembling the groove; 2122-peripheral wall; 2123-bottom wall; 2121 a-a first annular groove; 2121 b-a second annular groove; 2121 c-point of intersection; 2121 d-auxiliary groove; 2121e — a first connection point; 2121 f-second point of attachment.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are merely used to more clearly illustrate the technical solutions of the present application, and therefore are only examples, and the protection scope of the present application is not limited thereby.

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 herein 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.

In the description of the embodiments of the present application, the technical terms "first", "second", and the like are used only for distinguishing different objects, and are not to be construed as indicating or implying relative importance or implicitly indicating the number, specific order, or primary-secondary relationship of the technical features indicated. In the description of the embodiments of the present application, "a plurality" means two or more unless specifically defined otherwise.

Reference herein 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 application. 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. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of the present application, the term "and/or" is only one kind of association relationship describing an associated object, and means that three relationships may exist, for example, a and/or B, and may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

In the description of the embodiments of the present application, the term "plurality" refers to two or more (including two), and similarly, "plural sets" refers to two or more (including two), and "plural pieces" refers to two or more (including two).

In the description of the embodiments of the present application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the directions or positional relationships indicated in the drawings, and are only for convenience of description of the embodiments of the present application and for simplicity of description, but do not indicate or imply that the referred device or element must have a specific direction, be constructed and operated in a specific direction, and thus, should not be construed as limiting the embodiments of the present application.

In the description of the embodiments of the present application, unless otherwise explicitly stated or limited, the terms "mounted," "connected," "fixed," and the like are used in a broad sense, and for example, may be fixedly connected, detachably connected, or integrated; mechanical connection or electrical connection is also possible; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the embodiments of the present application can be understood by those of ordinary skill in the art according to specific situations.

At present, the application of the power battery is more and more extensive from the development of market situation. The power battery is not only applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles, electric automobiles and the like, and a plurality of fields such as military equipment and aerospace. With the continuous expansion of the application field of the power battery, the market demand of the power battery is also continuously expanding, and therefore, the recycling of the power battery is also particularly important.

The core unit of the power battery is a single battery, the single battery comprises an electrode assembly, electrolyte and a shell, the shell comprises an end cover and a shell, an anode tab of the electrode assembly is fixedly connected with an anode electrode terminal on the end cover, a cathode tab of the electrode assembly is fixedly connected with a cathode electrode terminal on the end cover, the electrode assembly is placed in the shell, the end cover is covered at an opening of the shell, the end cover is fixedly connected with the shell, and then the electrolyte is injected into the shell.

When the single battery needs to be recovered, the single battery is usually recovered by disassembling the casing of the single battery, and then taking out the electrode assembly. When disassembling the case, it is necessary to form an opening in the case using a tool such as a cutter, a pliers, or the like, and separate the case into two parts so as to take out the end cap together with the electrode assembly fixedly connected to the end cap, thereby recovering the electrode assembly. However, when the opening is performed in the housing by using a tool such as a cutter or pliers, it usually takes time and labor, and the disassembly is troublesome.

In view of this, embodiments of the present application provide a housing, which includes an end cap and a shell; the end cover is provided with a pressure relief part, and the pressure relief part is provided with a pressure relief groove; a disassembly groove is formed in the shell; the ratio of the depth of the disassembly groove to the thickness of the shell is L1, the ratio of the depth of the pressure relief groove to the thickness of the pressure relief part is L2, and L1 is less than L2.

In the single battery, due to the arrangement of the disassembly groove, when external force is provided, the shell can be separated at the disassembly groove, so that the disassembly is more convenient, and the recovery of the battery is more convenient; simultaneously, the groove depth proportion of disassembling the groove is less than the groove depth proportion of the pressure relief groove of pressure relief portion, and when the pressure or the temperature in the shell reached the threshold value, the shell will split along the pressure relief groove, realizes the pressure release, can make to disassemble the groove and do not influence the free normal use of battery.

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

The electric device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool 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 particularly limit the above electric devices.

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

Fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present application, please refer to fig. 1, where the vehicle 1000 may be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile may be a pure electric automobile, a hybrid electric automobile, or an extended range automobile. The battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may serve as an operation power source of the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to supply power to the motor 300, for example, for starting, navigation, and operational power requirements while the vehicle 1000 is traveling.

In some embodiments 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 for the vehicle 1000.

Fig. 2 is an exploded view of a battery 100 according to some embodiments of the present disclosure, referring to fig. 2, the battery 100 includes a case 10 and a battery cell 20, and the battery cell 20 is accommodated in the case 10. The case 10 is used to provide a receiving space for the battery cells 20, and the case 10 may have various structures. In some embodiments, the case 10 may include a first portion 11 and a second portion 12, the first portion 11 and the second portion 12 cover each other, and the first portion 11 and the second portion 12 together define a receiving space for receiving the battery cell 20. The second part 12 may be a hollow structure with one open end, the first part 11 may be a plate-shaped structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a containing space; the first portion 11 and the second portion 12 may be both hollow structures with one side open, and the open side of the first portion 11 may cover the open side of the second portion 12. Of course, the case 10 formed by the first and

second portions

11 and 12 may have various shapes, such as a cylinder, a rectangular parallelepiped, and the like.

In the battery 100, the number of the battery cells 20 may be multiple, and the multiple battery cells 20 may be connected in series or in parallel or in series-parallel, where in series-parallel refers to both series connection and parallel connection among the multiple battery cells 20. The plurality of battery cells 20 can be directly connected in series or in parallel or in series-parallel, and the whole formed by the plurality of battery cells 20 is accommodated in the box body 10; of course, the battery 100 may also be formed by connecting a plurality of battery cells 20 in series, in parallel, or in series-parallel to form a battery 100 module, and then connecting a plurality of battery 100 modules in series, in parallel, or in series-parallel to form a whole, and accommodating the whole in the case 10. The battery 100 may further include other structures, for example, the battery 100 may further include a bus member for achieving electrical connection between the plurality of battery cells 20.

Wherein each battery cell 20 may be a secondary battery 100 or a primary battery 100; but is not limited to, the lithium-sulfur battery 100, the sodium-ion battery 100, or the magnesium-ion battery 100. The battery cell 20 may be cylindrical, flat, rectangular parallelepiped, or other shape.

Fig. 3 is an exploded view of a battery cell 20 according to some embodiments of the present disclosure, please refer to fig. 3, in which the battery cell 20 is a minimum unit of the battery 100. As shown in fig. 3, the battery cell 20 includes a case 21, an electrode assembly 22, and other functional components; the housing 21 includes an end cap assembly 23 and a housing 212.

Fig. 4 is an exploded view of an end cap assembly 23 according to some embodiments of the present application, please refer to fig. 4. The end cap assembly 23 includes an end cap 231, and the end cap 231 refers to a member covering the opening of the case 212 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of end cap 231 may be adapted to the shape of housing 212 to fit housing 212. Alternatively, the end cap 231 may be made of a material (e.g., an aluminum alloy) having a certain hardness and strength, so that the end cap 231 is not easily deformed when being extruded and collided, and thus the battery cell 20 may have a higher structural strength and the safety performance may be improved.

With continued reference to fig. 3 and 4, the end cap 231 may further be provided with a pressure relief portion 232 for relieving the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold value. The material of the end cap 231 may also be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this embodiment. In some embodiments, an insulator 233 may also be provided on the inside of the end cap 231, and the insulator 233 may be used to isolate the electrical connection components within the housing 212 from the end cap 231 to reduce the risk of short circuits. Illustratively, the insulator 233 may be plastic, rubber, or the like.

Case 212 is an assembly for mating with end cap 231 to form the internal environment of battery cell 20, wherein the formed internal environment may be used to house electrode assembly 22, electrolyte, and other components. The housing 212 and the end cap 231 may be separate components, and an opening may be formed in the housing 212, and the opening may be covered by the end cap 231 to form the internal environment of the battery cell 20. Without limitation, the end cap 231 and the housing 212 may be integrated, and specifically, the end cap 231 and the housing 212 may form a common connecting surface before other components are inserted into the housing, and when it is necessary to enclose the inside of the housing 212, the end cap 231 covers the housing 212. The housing 212 may be a variety of shapes and sizes, such as rectangular parallelepiped, cylindrical, hexagonal prism, etc. Specifically, the shape of case 212 may be determined according to the specific shape and size of electrode assembly 22. The material of the housing 212 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this embodiment.

The electrode assembly 22 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 22 may be contained within case 212. The electrode assembly 22 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is typically disposed between the positive electrode sheet and the negative electrode sheet, and the separator may be made of PP (polypropylene) or PE (polyethylene).

Referring to fig. 3, the positive plate includes a positive electrode collector and a positive electrode active material layer, the positive electrode active material layer is coated on the surface of the positive electrode collector, the positive electrode collector without the positive electrode active material layer is protruded from the positive electrode collector coated with the positive electrode active material layer, and the positive electrode collector without the positive electrode active material layer is used as a positive electrode tab 222. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like.

The negative plate comprises a negative current collector and a negative active substance layer, the negative active substance layer is coated on the surface of the negative current collector, the negative current collector which is not coated with the negative active substance layer protrudes out of the negative current collector which is coated with the negative active substance layer, and the negative current collector which is not coated with the negative active substance layer is used as a negative pole tab 223. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that the fusing does not occur by a large current, the positive electrode tab 222 is in a plurality and is stacked, and the negative electrode tab 223 is in a plurality and is stacked.

With continued reference to fig. 3, the positive electrode tab 222 and the negative electrode tab 223 may be located at one end of the body portion 221 of the electrode assembly 22 together or at both ends of the body portion 221, respectively. The end cap 231 may be provided with functional components such as a positive electrode terminal 234 and a negative electrode terminal 235. The positive electrode terminal 234 may be electrically connected with the positive tab 222 of the electrode assembly 22, and the negative electrode terminal 235 may be electrically connected with the negative tab 223 of the electrode assembly 22 for outputting or inputting electric energy of the battery cell 20. During the charge and discharge of the battery 100, the positive and negative active materials react with the electrolyte, and the tabs are connected to the electrode terminals to form a current loop.

FIG. 5 is a schematic structural view of the housing 21 provided in some embodiments of the present application; FIG. 6 is a cross-sectional view taken along A-A of FIG. 5; fig. 7 is an enlarged view at B in fig. 6. Referring to fig. 3 to 7, a pressure relief portion 232 is disposed on the end cap 231, and a pressure relief groove 2321 is disposed on the pressure relief portion 232; the housing 212 is provided with a disassembly groove 2121; the ratio of the depth of the disassembly groove 2121 to the thickness of the housing 212 is L1, the ratio of the depth of the pressure relief groove 2321 to the thickness of the pressure relief portion 232 is L2, and L1 < L2.

The pressure relief part 232 on the end cap 231 refers to a metal thin film (for example, a copper, iron, aluminum, stainless steel, aluminum alloy, or other thin film) on the end cap 231, the pressure relief groove 2321 is formed in the metal thin film, and the pressure relief groove 2321 does not penetrate through two surfaces of the metal thin film, so that the metal thin film is an integral film layer, that is, when the internal pressure of the battery cell 20 is normal pressure, the metal thin film does not generate air leakage or the like, but the connection strength of the metal thin film at the pressure relief groove 2321 is lower than that at other positions of the metal thin film, and when the internal pressure or temperature of the battery cell 20 reaches a threshold value, the pressure relief groove 2321 on the pressure relief part 232 is cracked, so that the internal pressure can be relieved.

As shown in fig. 7, the depth of the pressure relief groove 2321 is L21, and the depth of the pressure relief groove 2321 is the groove depth of the pressure relief groove 2321, that is, the depth of the depression at the pressure relief groove 2321; a thickness of pressure relief portion 232 is L22, the thickness of pressure relief portion 232 is a sum of depth L21 of pressure relief groove 2321 and remaining thickness L23 of pressure relief portion 232 where pressure relief groove 2321 is provided, and L22= L21+ L23. The ratio of the depth of the relief groove 2321 to the thickness of the relief portion 232 is L2, L2= L21/L22.

The disassembly groove 2121 does not penetrate through the wall of the housing 212, so that the housing 212 is an integral layer structure, and the single battery 20 does not leak at the housing 212 when no external force is applied, but the connection strength of the housing 212 at the disassembly groove 2121 is lower than that at other positions of the housing 212, and when the disassembly groove 2121, the periphery or the edge of the disassembly groove is applied with an external force, the disassembly groove 2121 is easily separated from the disassembly groove 2121, so that the disassembly of the single battery 20 can be realized.

As shown in fig. 7, the depth of the disassembled groove 2121 is L11, and the depth of the disassembled groove 2121 is the groove depth of the disassembled groove 2121, that is, the depth of the depression at the disassembled groove 2121; the thickness of case 212 is L12, the thickness of case 212 is the sum of the depth L11 of the disassembly groove 2121 and the remaining thickness L13 of case 212 where disassembly groove 2121 is provided, L12= L11+ L13. The ratio of the depth of the disassembly groove 2121 to the thickness of the housing 212 is L1, L1= L11/L12.

In the above technical solution, the housing 212 of the housing 21 is provided with the disassembling groove 2121, when an external force is provided, the housing 212 can be separated from the disassembling groove 2121, so that the disassembling is more convenient; meanwhile, L1 is less than L2, and when the pressure or temperature inside the housing 21 reaches a threshold value, the pressure relief groove 2321 of the pressure relief portion 232 is cracked to realize pressure relief, so that the normal use of the battery cell 20 is not affected by the disassembly groove 2121.

In some embodiments, fig. 8 is a first schematic view of a housing 21 provided in some embodiments of the present application, fig. 9 is a second schematic view of a housing 21 provided in some embodiments of the present application, fig. 10 is a third schematic view of a housing 21 provided in some embodiments of the present application, fig. 11 is a fourth schematic view of a housing 21 provided in some embodiments of the present application, and fig. 12 is a fifth schematic view of a housing 21 provided in some embodiments of the present application; FIG. 13 is a sixth schematic view of a housing 21 provided in accordance with some embodiments of the present application; fig. 14 is a seventh schematic view of a housing 21 provided in some embodiments of the present application. Referring to fig. 2, 3 and 8 to 14, the end cap 231 covers the opening of the housing 212 and is welded to the edge of the opening of the housing 212, and the minimum distance D1 between the dismantling groove 2121 and the end cap 231 is greater than 0.3 cm.

With continued reference to fig. 3, the housing 212 includes a peripheral wall 2122 and a bottom wall 2123, the bottom wall 2123 is connected to one end of the peripheral wall 2122 and closes one end opening of the peripheral wall 2122, and the other end of the peripheral wall 2122 (the end opposite to the bottom wall 2123) is the opening of the housing 212. Alternatively, the bottom wall 2123 is integrally formed with the peripheral wall 2122, which may provide the housing 212 with greater strength. In other embodiments, the bottom wall 2123 and the peripheral wall 2122 can be formed separately and then welded or bonded together.

Referring to fig. 8-14, the welding of the end cap 231 to the opening edge of the housing 212 may form a welding heat effect region at the welding area of the end cap 231 and the housing 212 and around the welding area, and generally, the width of the welding heat effect region is less than 0.3 cm.

The end cap 231 may be a substantially flat plate structure, the end cap 231 has a first surface close to the housing 212 and a second surface away from the housing 212, the disassembling groove 2121 may have one (as shown in fig. 8 to 10), two (as shown in fig. 11 and 12), three (as shown in fig. 13 and 14), and the like, and the minimum distance D1 between the disassembling groove 2121 and the end cap 231 is: the distance between the closest point of the dismantling groove 2121 to the opening of the housing 212 and the first surface of the end cap 231.

In the above technical solution, the minimum distance D1 between the dismantling groove 2121 and the end cap 231 is greater than 0.3cm, so that the region where the dismantling groove 2121 is disposed is kept away from the region of the welding heat effect, thereby making the overall strength of the housing 21 higher.

Referring to fig. 3 and 8 to 14, the minimum distance between the dismantling groove 2121 and the main body 221 of the electrode assembly 22 is greater than 0.

The body portion 221 of the electrode assembly 22 refers to: a portion of the electrode assembly 22 having an active material layer, a lower portion of the electrode assembly 22 (excluding the positive electrode tab 222 and the negative electrode tab 223 extending outside the body portion 221) as shown in fig. 3, and a dotted-line frame portion as shown in fig. 8 to 14. The minimum distance D2 between the dismantling groove 2121 and the main body portion 221 of the electrode assembly 22 is: a distance between a point of the disassembly groove 2121 farthest from the opening of the housing 212 and the main body portion 221.

In the above-mentioned solution, if the external force is applied to disassemble the case 212 at the disassembly groove 2121, a part of the case 212 may move toward the inside of the case 212, and the position of the disassembly groove 2121 is limited on the body part 221, so that the part moving toward the inside of the case 212 may not pierce the body part 221 of the electrode assembly 22, so as to recover the electrode assembly 22. In some embodiments, with continued reference to fig. 8-10, the disassembly groove 2121 includes a first annular groove 2121a, and the first annular groove 2121a is circumferentially disposed on the peripheral wall 2122. The first annular groove 2121a is formed in a circle along the circumferential direction of the circumferential wall 2122, and the first annular groove 2121a is connected end to form an annular closed groove.

The first annular groove 2121a may extend in the X direction (see fig. 8), may extend obliquely (see fig. 9), or may extend in a curved manner (see fig. 10), and the first annular groove 2121a may be provided in a single turn around the circumferential wall 2122.

In the above technical solution, an external force may be applied along the first annular groove 2121a, and may be pressed by a hand, or an external force may be applied by another tool to split the case 212 along the first annular groove 2121a, so that the case 212 is separated into two parts at the first annular groove 2121a, so as to take out the electrode assembly 22 inside the case 21, and recover the battery 100.

In some embodiments, the angle between the face of the first annular groove 2121a and the face of the opening of the peripheral wall 2122 is less than 5 °.

Referring to fig. 8, the first annular groove 2121a extends along the X direction, and the surface of the first annular groove 2121a is parallel to the surface of the opening of the peripheral wall 2122, and the included angle therebetween is 0 °.

With continued reference to fig. 9, the first annular groove 2121a extends obliquely, and the angle α between the surface of the first annular groove 2121a and the surface of the opening of the peripheral wall 2122 is smaller than 5 °.

Referring to fig. 10, if the extending direction of the first annular groove 2121a is irregular, the surface of the first annular groove 2121a is a surface formed by a straight line along a direction perpendicular to the paper surface, the straight line being formed by a point of the first annular groove 2121a farthest from the end cap 231 and a point of the first annular groove 2121a closest to the end cap 231, as shown in fig. 10, an included angle α between the surface of the first annular groove 2121a and the surface of the opening of the peripheral wall 2122 is α, and α is smaller than 5 °.

Illustratively, the angle α between the surface of the first annular groove 2121a and the surface of the opening of the peripheral wall 2122 may be 0 °, 1 °, 2 °, 3 °, 4 °, or 5 °, which may also be any value within the above range.

In the above technical solution, the surface where the first annular groove 2121a is located is substantially parallel to the surface where the opening of the peripheral wall 2122 is located, and the annular groove can be formed for disassembly, and the length of the annular groove is short, so that the strength of the housing 21 can be ensured to a certain extent.

In other embodiments, a non-closed groove may be further disposed on the peripheral wall 2122, and a tool may be used to open the non-closed groove to disassemble the housing, so that the disassembly may be more convenient.

In some embodiments, with continued reference to FIG. 11, the disassembly groove 2121 further includes a second annular groove 2121b, the second annular groove 2121b is circumferentially disposed in the peripheral wall 2122, and the first annular groove 2121a intersects the second annular groove 2121 b. The second annular groove 2121b is provided in a circle along the circumferential direction of the circumferential wall 2122, and the end-to-end connection of the second annular groove 2121b forms an annular closed groove.

As shown in fig. 11, each of the first and second

annular grooves

2121a and 2121b extends obliquely so that the first and second

annular grooves

2121a and 2121b intersect. In another embodiment, the first annular groove 2121a may extend in the X direction, and the second annular groove 2121b may extend obliquely such that the first annular groove 2121a and the second annular groove 2121b intersect. In another embodiment, the first annular groove 2121a may extend in the X direction, and the second annular groove 2121b may extend in a curved manner such that the first annular groove 2121a and the second annular groove 2121b intersect. In another embodiment, the first annular groove 2121a may extend obliquely, and the second annular groove 2121b may extend in a curved manner such that the first annular groove 2121a and the second annular groove 2121b intersect.

In the above technical solution, when the housing 21 is disassembled, an external force may be applied to the intersection 2121c of the first annular groove 2121a and the second annular groove 2121b, and the disassembly is performed with this as a starting point, which is more labor-saving; meanwhile, when the external force is continuously applied for disassembly, the external force can be applied along the area between the two annular grooves, so that the disassembly is more convenient, the scratch on hands is avoided, and the disassembly is more convenient.

In some embodiments, with continued reference to fig. 11, the intersection 2121c of the first annular groove 2121a and the second annular groove 2121b is closer to the positive electrode terminal 234 than the intersection 2121c is to the negative electrode terminal 235. That is, the intersection 2121c is disposed on the side of the case 212 close to the positive electrode terminal 234.

In the above technical solution, when the external force is applied to disassemble, the shell 212 is split from the intersection 2121c, which may cause the shell 212 at the edge of the intersection 2121c to move inward, and thus may contact with the tab; by disposing intersection 2121c close to the positive electrode side, contact between case 212 and the negative electrode can be avoided, thereby improving safety of battery 100 during disassembly.

In some embodiments, with continued reference to fig. 11, the housing 212 is a rectangular parallelepiped, and the peripheral wall 2122 of the housing 212 is also a rectangular parallelepiped, so that two opposite surfaces with larger area in the peripheral wall 2122 of the housing 212 are large surfaces, and two opposite surfaces with smaller area in the peripheral wall 2122 are side surfaces. The intersection 2121c of the first annular groove 2121a and the second annular groove 2121b is located on the large surface, and when the intersection of the first annular groove 2121a and the second annular groove 2121b is pressed by a hand, the force bearing area of the hand can be large, so that the hand can be prevented from being scratched.

In some embodiments, with continued reference to fig. 12, the disassembly groove 2121 further includes a second annular groove 2121b, the second annular groove 2121b is circumferentially disposed in the peripheral wall 2122, and the second annular groove 2121b is located on a side of the first annular groove 2121a away from the end cap 231. When the shell 21 is disassembled, external force is directly applied to the area between the two annular grooves, so that the disassembly is more convenient, the scratch on hands is avoided, and the disassembly is more convenient.

In some embodiments, the angle between the face of the second annular groove 2121b and the face of the opening of the perimeter wall 2122 is less than 5 °.

Referring to fig. 12, the second annular groove 2121b extends along the X direction, and a plane of the second annular groove 2121b is parallel to a plane of the opening of the peripheral wall 2122, and an included angle therebetween is 0 °.

In another embodiment, the second annular groove 2121b extends obliquely, and the angle between the plane of the second annular groove 2121b and the plane of the opening of the peripheral wall 2122 is less than 5 °. In another embodiment, the extending direction of the second annular groove 2121b is irregular, so that the second annular groove 2121b is a plane formed by a straight line in the direction perpendicular to the paper plane, the straight line formed by a point of the second annular groove 2121b farthest from the end cap 231 and a point of the second annular groove 2121b closest to the end cap 231, and an included angle between the plane of the second annular groove 2121b and a plane of the opening of the peripheral wall 2122 is less than 5 °.

Illustratively, the angle between the surface of the second annular groove 2121b and the surface of the opening of the peripheral wall 2122 may be 0 °, 1 °, 2 °, 3 °, 4 °, or 5 °, which may also be any value within the above range.

In the above technical solution, the surface where the second annular groove 2121b is located is substantially parallel to the surface where the opening of the peripheral wall 2122 is located, and the annular groove can be formed so as to be disassembled, and the length of the annular groove is short, so that the strength of the housing 21 can be ensured to a certain extent.

In some embodiments, with continued reference to fig. 13 and 14, the disassembly groove 2121 further includes an auxiliary groove 2121d, the auxiliary groove 2121d is disposed on the peripheral wall 2122, and two ends of the auxiliary groove 2121d are respectively connected to the first annular groove 2121a and the second annular groove 2121 b.

As shown in fig. 13 and 14, both ends of the auxiliary groove 2121d communicate with the first annular groove 2121a and the second annular groove 2121b, respectively, so that the auxiliary groove 2121d forms a disassembly groove 2121 together with the first annular groove 2121a and the second annular groove 2121b to disassemble the housing 212.

In another embodiment, both ends of the auxiliary groove 2121d may extend through the first annular groove 2121a and the second annular groove 2121b, that is, both ends of the auxiliary groove 2121d extend beyond the first annular groove 2121a and the second annular groove 2121b, and the auxiliary groove 2121d may form a disassembly groove 2121 together with the first annular groove 2121a and the second annular groove 2121b to disassemble the housing 212.

In the above technical solution, when the housing 21 is disassembled, an external force may be applied to the intersection of the first annular groove 2121a, the second annular groove 2121b and the auxiliary groove 2121d, and the disassembly is performed with this as a starting point, which is more labor-saving; meanwhile, when the external force is continuously applied for disassembly, the external force can be applied along the area between the two annular grooves, so that the disassembly is more convenient, the scratch on hands is avoided, and the disassembly is more convenient.

In some embodiments, the connection of the auxiliary groove 2121d and the first annular groove 2121a is a first connection point 2121e, the connection of the auxiliary groove 2121d and the second annular groove 2121b is a second connection point 2121f, and the distance between the first connection point 2121e and the second connection point 2121f is the minimum distance between the first annular groove 2121a and the second annular groove 2121 b.

As shown in fig. 13 and 14, a connection line between the first connection point 2121e and the second connection point 2121f extends in the Y direction, and the length of the auxiliary groove 2121d is relatively short, so that the strength of the housing 21 can be ensured to some extent while the convenient disassembly can be achieved.

In some embodiments, the auxiliary grooves 2121d are line-segment grooves, and the extending direction of the line-segment grooves forms an angle of 85 ° to 90 ° with the surface of the peripheral wall 2122 on which the opening is located. As shown in fig. 13, the auxiliary groove 2121d extends in the Y direction, and the extending direction of the auxiliary groove 2121d forms an angle of 90 ° with the surface of the peripheral wall 2122 on which the opening is located. In other embodiments, the angle between the extending direction of the auxiliary groove 2121d and the surface of the peripheral wall 2122 on which the opening is located may be 85 °, 86 °, 87 °, 88 °, or 89 °, which may be any value within the above range.

The auxiliary groove 2121d extends in a direction substantially perpendicular to the surface of the peripheral wall 2122 on which the opening is formed, and the auxiliary groove 2121d can be formed for disassembly while the length of the auxiliary groove 2121d is made short, so that the strength of the housing 21 can be secured to some extent.

In some embodiments, with continued reference to fig. 13, the distance between the auxiliary groove 2121d and the positive electrode terminal 234 is smaller than the distance between the auxiliary groove 2121d and the negative electrode terminal 235. That is, the auxiliary groove 2121d is provided on the side of the case 212 close to the positive electrode terminal 234.

In the above technical solution, when the external force is applied to perform the disassembly, the housing 212 is split from the auxiliary groove 2121d, which may cause the housing 212 at the edge of the auxiliary groove 2121d to move inward, and thus may contact with the tab; by disposing the auxiliary groove 2121d close to the positive electrode side, the case 212 is prevented from contacting the negative electrode, thereby improving the safety of the battery 100 during disassembly.

In some embodiments, and with continued reference to fig. 13 and 14, the housing 212 is square, and the perimeter wall 2122 of the housing 212 is also square, defining two oppositely disposed surfaces with larger areas as large surfaces and two oppositely disposed surfaces with smaller areas as side surfaces in the perimeter wall 2122 of the housing 212. The auxiliary groove 2121d is provided on the large surface of the peripheral wall 2122 such that a first connection point 2121e where the auxiliary groove 2121d intersects the first annular groove 2121a and a second connection point 2121f where the auxiliary groove 2121d intersects the second annular groove 2121b are located at the large surface.

Among the above-mentioned technical scheme, can make the setting of auxiliary groove 2121d more convenient, simultaneously, when exerting external force to the edge of auxiliary groove 2121d and the position between two ring channels, also more convenient.

In some embodiments, the minimum distance between the first and second

annular grooves

2121a, 2121b is no less than 1.5 cm.

With continued reference to fig. 13 and 14, the first annular groove 2121a and the second annular groove 2121b both extend in the X direction, and the minimum distance between the first annular groove 2121a and the second annular groove 2121b is the distance between the first annular groove 2121a and the second annular groove 2121 b.

In another embodiment, if the first and second

annular grooves

2121a and 2121b are obliquely disposed, the minimum distance between the first and second

annular grooves

2121a and 2121b may be: there are several line segments along the Y direction, two ends of the line segment are respectively located in the first annular groove 2121a and the second annular groove 2121b, and the length of the shortest line segment is the minimum distance between the first annular groove 2121a and the second annular groove 2121 b.

Among the above-mentioned technical scheme, can make things convenient for the application of external force, for example: when the position between the first annular groove 2121a and the second annular groove 2121b is pressed by hand, the hand is not scratched.

In some embodiments, the break-down groove 2121 is a break-down score. Generally, the disassembly nicks can be formed by a tool with a tip in a scribing mode, the disassembly nicks are more convenient to set, the width of the nicks is smaller, and the influence on the strength, the attractiveness and the like of the shell 212 is smaller.

In some embodiments, the disassembly groove 2121 is recessed from the outside inward. The housing 212 may be formed first and then the outer surface of the peripheral wall 2122 of the housing 212 may be provided with the disassembly groove 2121; the housing 212 may be formed after the disassembly groove 2121 is provided. The notch of the disassembly groove 2121 is located on the outer surface of the housing 212, so that the position of the disassembly groove 2121 can be conveniently observed, and when the housing 21 needs to be disassembled, the position of the disassembly groove 2121 can be easily found and the disassembly is performed.

In other embodiments, the disassembly groove 2121 may also be recessed from the inside to the outside. The housing 212 may be formed after the disassembly groove 2121 is formed, without affecting the appearance of the housing 212.

With continued reference to fig. 3 and 13, the present embodiment provides a square housing 21, the housing 21 includes an end cap 231 and a housing 212, the housing 212 includes a peripheral wall 2122 and a bottom wall 2123, the bottom wall 2123 is located at one end of the peripheral wall 2122 and is integrally formed with the peripheral wall 2122, the peripheral wall 2122 is opened at an end opposite to the bottom wall 2123, and the end cap 231 and the peripheral wall 2122 are welded at an opening edge. The peripheral wall 2122 is provided with a first annular groove 2121a, a second annular groove 2121b and an auxiliary groove 2121d, the first annular groove 2121a and the second annular groove 2121b are circumferentially arranged on the peripheral wall 2122, the second annular groove 2121b is located on the side, away from the end cap 231, of the first annular groove 2121a, the two ends of the auxiliary groove 2121d are respectively connected with the first annular groove 2121a and the second annular groove 2121b, and the auxiliary groove 2121d is located on the large surface of the peripheral wall 2122. The minimum distance D1 between the first annular groove 2121a and the end cap 231 is > 0.3 cm.

In such a case 21, when the battery cell 20 needs to be disassembled, the case 212 may be broken from the auxiliary groove 2121d by directly pressing the edge of the auxiliary groove 2121d with a hand, and then the region between the first annular groove 2121a and the second annular groove 2121b may be continuously pressed with a hand, so that a break may be formed in the case 212 to remove the electrode assembly 22 in the battery cell 20. Meanwhile, the minimum distance D1 between the first annular groove 2121a and the end cap 231 is greater than 0.3cm, so that the influence of the welding heat effect on the strength of the housing 212 can be avoided.

With continued reference to fig. 3 and 13, an embodiment of the present application provides a prismatic battery cell 20, the battery cell 20 includes a prismatic case 21 and an electrode assembly 22, the case 21 includes an end cap 231 and a case 212, the case 212 includes a peripheral wall 2122 and a bottom wall 2123, the bottom wall 2123 is located at one end of the peripheral wall 2122 and is integrally formed with the peripheral wall 2122, the peripheral wall 2122 is open at an end opposite to the bottom wall 2123, the electrode assembly 22 is disposed in a cavity formed by the peripheral wall 2122 and the bottom wall 2123, and the end cap 231 and the peripheral wall 2122 are welded at an edge of the opening. The peripheral wall 2122 is provided with a first annular groove 2121a, a second annular groove 2121b and an auxiliary groove 2121d, the first annular groove 2121a and the second annular groove 2121b are circumferentially arranged on the peripheral wall 2122, the second annular groove 2121b is located on the side of the first annular groove 2121a far away from the end cap 231, and two ends of the auxiliary groove 2121d are respectively connected with the first annular groove 2121a and the second annular groove 2121 b. The minimum distance D1 between the first annular groove 2121a and the end cap 231 is > 0.3cm, and the minimum distance between the second annular groove 2121b and the main portion 221 of the electrode assembly 22 is greater than 0.

In such a battery cell 20, when the battery cell 20 needs to be disassembled, the case 212 may be broken from the auxiliary groove 2121d by directly pressing the edge of the auxiliary groove 2121d with a hand, and then the region between the first annular groove 2121a and the second annular groove 2121b may be continuously pressed with a hand, so that a break is formed in the case 212, so as to remove the electrode assembly 22 from the battery cell 20. Meanwhile, the minimum distance D1 between the first annular groove 2121a and the end cover 231 is more than 0.3cm, so that the influence of the welding heat effect on the strength of the shell 212 can be avoided; the minimum distance between the second annular groove 2121b and the main body 221 of the electrode assembly 22 is greater than 0, so that the main body 221 is prevented from being punctured by pressing the entering part of the case 212 inwards, and the recycling effect of the electrode assembly 22 is improved.

Example 1

Referring to fig. 3 and 13, the battery cell 20 includes an electrode assembly 22 and a case 21, the case 21 includes a case 212 and an end cap 231, the electrode assembly 22 is disposed in the case 212, and the end cap 231 is welded to an opening edge of the case 212. The peripheral wall 2122 of the housing 212 is provided with a first annular notch and a second annular notch which are parallel and along the X direction; an auxiliary nick along the Y direction is also arranged; the distance between the first annular score and the end cap 231 is 0.5cm, the distance between the first annular score and the second annular score is 1.5cm, the distance between the second annular score and the main body portion 221 of the electrode assembly 22 is 0.5cm, the ratio of the score depth to the thickness of the case 212 is 0.2, and the ratio of the depth of the pressure relief groove 2321 of the pressure relief portion 232 on the end cap 231 to the thickness of the pressure relief portion 232 is 0.3.

Example 2

Referring to fig. 3 and 8, the battery cell 20 includes an electrode assembly 22 and a case 21, the case 21 includes a case 212 and an end cap 231, the electrode assembly 22 is disposed in the case 212, and the end cap 231 is welded to an opening edge of the case 212. A first parallel annular notch is provided in the peripheral wall 2122 of the housing 212 along the X direction; the distance between the first annular score and the end cap 231 is 0.5cm, the ratio of the score depth to the thickness of the shell 212 is 0.2, and the ratio of the depth of the pressure relief groove 2321 of the pressure relief portion 232 on the end cap 231 to the thickness of the pressure relief portion 232 is 0.3.

Example 3

Example 3 differs from example 1 in that: the end cap 231 is glued to the open edge of the housing 212 and the first annular score is 0.2cm from the end cap 231.

Comparative example 1

The battery cell comprises an electrode assembly and a shell, wherein the shell comprises a shell body and an end cover, the electrode assembly is arranged in the shell body, the end cover is welded on the edge of an opening of the shell body, and the peripheral wall of the shell body is not scored.

Comparative example 2

Comparative example 2 differs from example 1 in that: the first annular score is 0.2cm from the end cap 231.

Comparative example 3

Comparative example 3 differs from example 1 in that: the ratio of the score depth to the thickness of the case 212 was 0.2, and the ratio of the depth of the relief groove 2321 of the relief portion 232 on the end cap 231 to the thickness of the relief portion 232 was 0.1.

Experimental example 1

The battery cells provided in examples 1 to 3 and comparative examples 1 to 3 were fully charged and disassembled, wherein the battery cells provided in examples 1 to 3 and comparative examples 2 to 3 were disassembled by pressing with hands, the battery cell provided in comparative example 1 was disassembled with a cutter, and the time for disassembling the case was recorded as shown in table 1.

TABLE 1 disassembly time of the housing in the cell

Serial number	Time for disassembling housing
		Example 1	0.25min
Example 2	0.25min
		Example 3	0.25min
Comparative example 1	5min
		Comparative example 2	0.25min
Comparative example 3	0.25min

As can be seen from table 1, after the disassembly nicks are provided on the housing, the housing can be disassembled by pressing with hands, and the disassembly efficiency is also high.

Experimental example 2

The battery cells provided in examples 1 to 3 and comparative examples 1 to 3 were overcharged, and the safety performance (national standard: GBT/31485) of the battery cells was recorded as shown in Table 2.

TABLE 2 safety Performance of the Battery cell

Serial number	Overcharge test @60 ℃ 200A 4.7V
		Example 1	Breaking of pressure relief groove of pressure relief portion of end cap, HL4
Example 2	Breaking of pressure relief groove of pressure relief portion of end cap, HL4
		Example 3	Breaking of pressure relief groove of pressure relief portion of end cap, HL4
Comparative example 1	Breaking of pressure relief groove of pressure relief portion of end cap, HL4
		Comparative example 2	Breaking at the shell notch, flying out of the shell, HL6
Comparative example 3	Breaking at the notch of the shell, the shell flying out, HL6

It can be seen that combining table 1 and table 2, the mode that this application provided sets up disassembles the nick, not only can realize the quick disassembly of casing, can also make the free security performance of battery can ensure.

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 case for housing an electrode assembly, the case comprising:

the end cover is provided with a pressure relief part, and the pressure relief part is provided with a pressure relief groove;

the shell is provided with a disassembling groove;

the ratio of the depth of the disassembly groove to the thickness of the shell is L1, the ratio of the depth of the pressure relief groove to the thickness of the pressure relief part is L2, and L1 is less than L2.

2. The shell of claim 1, wherein the end cap is covered at the opening of the shell and welded with the edge of the opening of the shell, and the minimum distance D1 between the dismantling groove and the end cap is more than 0.3 cm.

3. The housing of claim 1, wherein the shell includes a peripheral wall and the un-mating groove includes a first annular groove circumferentially disposed in the peripheral wall.

4. A casing according to claim 3, wherein the angle between the face of the first annular groove and the face of the opening of the peripheral wall is less than 5 °.

5. The housing of claim 3, wherein the un-mating groove further comprises a second annular groove circumferentially disposed at the peripheral wall, the first annular groove intersecting the second annular groove.

6. The housing of claim 5, wherein the end cap is further provided with a positive electrode terminal and a negative electrode terminal, and a distance between an intersection of the first annular groove and the second annular groove and the positive electrode terminal is smaller than a distance between the intersection and the negative electrode terminal.

7. The housing of claim 3, wherein the un-mating groove further comprises a second annular groove circumferentially disposed in the peripheral wall, the second annular groove being located on a side of the first annular groove remote from the end cap.

8. A casing according to claim 7, wherein the angle between the face of the second annular groove and the face of the opening in the peripheral wall is less than 5 °.

9. The housing of claim 7, wherein the disassembly groove further comprises an auxiliary groove disposed in the peripheral wall, and both ends of the auxiliary groove are connected to the first annular groove and the second annular groove, respectively.

10. The housing of claim 9, wherein the junction of the auxiliary groove and the first annular groove is a first junction point, the junction of the auxiliary groove and the second annular groove is a second junction point, and the distance between the first junction point and the second junction point is a minimum distance between the first annular groove and the second annular groove.

11. The housing according to claim 10, wherein the auxiliary groove is a line-segment groove, and an angle between an extending direction of the line-segment groove and a surface of the peripheral wall on which the opening is located is 85 ° to 90 °.

12. The housing of claim 9, wherein the end cap further comprises a positive electrode terminal and a negative electrode terminal, and the auxiliary groove is spaced from the positive electrode terminal by a distance smaller than the auxiliary groove.

13. The enclosure of claim 9, wherein said peripheral wall is square, said peripheral wall including two oppositely disposed large faces of larger area and two oppositely disposed side faces of smaller area, said auxiliary slot being disposed in said large faces.

14. The housing according to any one of claims 7 to 13, wherein a minimum distance between the first annular groove and the second annular groove is not less than 1.5 cm.

15. An enclosure according to any one of claims 3 to 13, wherein the housing further comprises a bottom wall;

the bottom wall is positioned at one end of the peripheral wall and is integrally formed with the peripheral wall, and the peripheral wall forms an opening at the end opposite to the bottom wall.

16. The shell according to any one of claims 1 to 13, wherein the un-mating groove is an un-mating score.

17. The enclosure of any one of claims 1 to 13, wherein the un-mating groove is recessed from the outside to the inside.

18. A battery cell, comprising:

the enclosure of any one of claims 1 to 17,

the electrode assembly is placed in the shell, and the end cover is covered at the opening of the shell.

19. The battery cell of claim 18, wherein the minimum distance of the un-mating groove from the main portion of the electrode assembly is greater than 0.

20. A battery, comprising:

a battery cell according to claim 18 or 19;

and the box body is used for accommodating the battery monomer.

21. An electrical device comprising a battery as claimed in claim 20 for providing electrical energy.