Battery monomer, battery device and electric equipment

Abstract

The utility model provides a battery monomer, a battery device and electric equipment. The battery monomer comprises a shell, a battery cell assembly, an end cover and a first current collecting plate, the shell is provided with an opening; the battery core assembly is arranged in the shell; the end cover covers the opening; the end cover comprises a cover body and a convex part which protrudes towards one side of the battery core assembly; the convex part is adjacent to the edge of the cover body; the first collector plate is arranged between the end cover and the battery cell assembly; the surface, close to the first flow collecting plate, of the convex part is attached to the partial surface, close to the convex part, of the first flow collecting plate; and the edge of the first current collecting plate is deformed and bent towards the direction close to the battery core assembly relative to the center of the first current collecting plate. Through the arrangement, the gap between the convex part and the first collector plate after the edge of the first collector plate deforms and bends towards the direction close to the battery cell assembly relative to the center of the first collector plate is reduced, and the connection stability between the convex part of the end cover and the first collector plate is kept.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and particularly to battery cells, battery devices, and electrical equipment. Background Art

[0002] A battery cell generally includes a housing, a cell assembly, and a first current collector plate. The housing includes an end cap and a casing, and the first current collector plate is located between the cell assembly and the end cap. After the cell is installed in the casing, the first current collector plate is provided at the end of the cell assembly, and the end cap is covered on the end of the casing to achieve encapsulation and maintain the sealing and reliability of the housing structure.

[0003] However, problems such as poor soldering or soldering through are likely to occur during the soldering process between the end cap and the first current collector plate. Summary of the Utility Model

[0004] This application provides a battery cell, a battery device, and an electrical equipment to reduce the gap between the end cap and the first current collector plate.

[0005] To solve the above technical problems, a first aspect of this application provides a battery cell, including a casing, a cell assembly, an end cap, and a first current collector plate; the casing has an opening; the cell assembly is arranged in the casing; the end cap covers the opening; the end cap includes a cap body and a convex portion protruding toward the cell assembly side; the convex portion is arranged adjacent to the edge of the cap body; the first current collector plate is arranged between the end cap and the cell assembly; the surface of the convex portion close to the first current collector plate is arranged in contact with a partial surface of the first current collector plate close to the convex portion; the edge of the first current collector plate is deformed and bent in a direction close to the cell assembly relative to the center of the first current collector plate.

[0006] Since the surface of the convex portion close to the first current collector plate is arranged in contact with a partial surface of the first current collector plate close to the convex portion, the gap between the convex portion and the first current collector plate caused by the deformation and bending of the edge of the first current collector plate in a direction close to the cell assembly relative to the center of the first current collector plate is reduced, making it not easy for problems such as poor soldering or soldering through to occur during the soldering process between the convex portion of the end cap and the first current collector plate, and improving the connection stability between the convex portion of the end cap and the first current collector plate.

[0007] In one embodiment, the surface of the convex portion close to the first current collector plate is an inclined surface.

[0008] By setting the surface of the convex portion close to the first current collector plate as an inclined surface, the surface of the convex portion close to the first current collector plate is matched with the deformation and bending of the edge of the first current collector plate, maintaining the contact between the surface of the convex portion close to the first current collector plate and a partial surface of the first current collector plate close to the convex portion, which is beneficial to reducing the gap between the convex portion and the first current collector plate and maintaining the connection stability between the convex portion of the end cap and the first current collector plate.

[0009] In one embodiment, the surface of the convex portion close to the first current collector plate is an inclined plane or an arc surface.

[0010] By setting the surface of the convex part close to the first current collector plate as a plane or an arc surface, the deformation and bending of the edge of the first current collector plate are matched with the surface of the convex part close to the first current collector plate, and the surface of the convex part close to the first current collector plate is closely attached to the part of the surface of the first current collector plate close to the convex part, which is beneficial to reducing the gap between the convex part and the first current collector plate and maintaining the connection stability between the convex part of the end cover and the first current collector plate.

[0011] In one embodiment, the surface of the convex part close to the first current collector plate is an inclined plane, and the acute angle formed between the surface of the convex part close to the first current collector plate and the cover body is 3°-7°.

[0012] By making the above settings for the inclined surface of the convex part close to the first current collector plate, the deformation and bending of the edge of the first current collector plate are matched with the surface of the convex part close to the first current collector plate, and the tightness of the fit between the surface of the convex part close to the first current collector plate and the part of the surface of the first current collector plate close to the convex part is maintained, which is beneficial to reducing the gap between the convex part and the first current collector plate and maintaining the connection stability between the convex part of the end cover and the first current collector plate.

[0013] In one embodiment, the surface of the convex part close to the first current collector plate is an inclined concave arc surface.

[0014] By setting the surface of the convex part close to the first current collector plate as an inclined concave arc surface, the shape of the surface of the convex part close to the first current collector plate is matched with the deformation and bending shape of the edge of the first current collector plate, and the tightness of the fit between the surface of the convex part close to the first current collector plate and the part of the surface of the first current collector plate close to the convex part is maintained, which is beneficial to reducing the gap between the convex part and the first current collector plate and maintaining the connection stability between the convex part of the end cover and the first current collector plate.

[0015] In one embodiment, the convex part is spaced from the edge of the cover body, and the edge of the cover body is fixedly connected to the housing; along the radial direction from the center to the edge of the end cover, the height of the convex part gradually increases.

[0016] By setting that along the radial direction from the center to the edge of the end cover, the height of the convex part gradually increases, the part where the height of the convex part increases fills the space formed by the deformation and bending of the edge of the first current collector plate, and the surface of the convex part close to the first current collector plate is closely attached to the part of the surface of the first current collector plate close to the convex part, which is beneficial to reducing the gap between the convex part and the first current collector plate and maintaining the connection stability between the convex part of the end cover and the first current collector plate.

[0017] In one embodiment, the height of the convex portion near the outer edge of the surface of the first current collector plate relative to the edge of the cover body is a first value; when the first current collector plate is in a flat state, the surface of the portion of the first current collector plate configured to contact the convex portion is a plane, and the distance between the surface of the first current collector plate facing away from the battery cell assembly and the end face of the housing is a second value; the first value is greater than the second value.

[0018] By setting the first value to be greater than the second value, after the battery cell assembly and the first current collector plate are assembled in the housing, the assembly space left in the housing is in interference fit with the end cover, maintaining the fixation of the positions of the structural members in the housing and reducing the shaking and displacement of the structural members in the housing. Since there is a certain interference amount during the assembly of the end cover and the housing, the edge of the first current collector plate is squeezed by the convex portion of the end cover, and the edge of the first current collector plate bends and deforms in the direction close to the battery cell assembly. Even if the edge of the first current collector plate bends and deforms, the deformed edge of the first current collector plate is arranged in contact with the surface of the convex portion near the first current collector plate, reducing the gap between the convex portion and the first current collector plate and maintaining the connection stability between the convex portion of the end cover and the first current collector plate.

[0019] In one embodiment, the difference between the first value and the second value is 0.2 mm - 0.4 mm.

[0020] Through the above design of the difference between the first value and the second value, the interference amount during the assembly of the end cover and the housing is more appropriate, and the bending deformation of the edge of the first current collector plate is smaller. By setting the surface of the convex portion near the first current collector plate to be an inclined surface, the surface of the convex portion near the first current collector plate can be arranged in contact with a part of the surface of the first current collector plate near the convex portion, reducing the gap between the convex portion and the first current collector plate and maintaining the connection stability between the convex portion of the end cover and the first current collector plate.

[0021] In one embodiment, the first current collector plate includes a plate body and a convex block provided on the surface of the plate body near the convex portion. The surface of the convex block near the convex portion is arranged in contact with the surface of the convex portion near the convex block, and the surface of the convex block near the convex portion is an inclined surface.

[0022] By setting the surface of the convex block near the convex portion to be an inclined surface, after the edge of the first current collector plate bends and deforms, the convex block of the first current collector plate can be in good contact with the convex portion of the end cover, which is beneficial to reducing the gap between the convex portion and the convex block of the first current collector plate and maintaining the connection stability between the convex portion of the end cover and the first current collector plate.

[0023] In one embodiment, along the radial direction of the battery cell, the width of the convex portion is 2 mm - 4 mm.

[0024] By setting the width of the convex part as described above, the stability of the connection between the convex part and the first current collector plate is maintained, the shaking or movement of the first current collector plate in the housing is reduced, and further, the ear tab connected to the first current collector plate is prevented from shaking or shifting inside the battery, thus reducing problems such as poor contact or short circuit caused by the movement of the ear tab.

[0025] In one embodiment, the surface of the convex part close to the first current collector plate is welded to the surface of the first current collector plate close to the convex part.

[0026] By setting the welding between the surface of the convex part close to the first current collector plate and the surface of the first current collector plate close to the convex part, the stability of the connection between the convex part and the first current collector plate and the relatively high connection strength are maintained. At the same time, the surface of the convex part close to the first current collector plate is arranged in a fitting manner with a part of the surface of the first current collector plate close to the convex part, and the welding between the convex part and the first current collector plate can reduce the risk of false soldering or soldering through.

[0027] In one embodiment, the end cover includes a plurality of convex parts, and the plurality of convex parts are arranged at intervals along the circumferential direction of the cover body.

[0028] By arranging the plurality of convex parts at intervals along the circumferential direction of the cover body, a gap is formed between adjacent convex parts, and this gap can be used for air conduction. When a thermal runaway state occurs inside the battery cell assembly, such as the runaway point being close to the edge of the end cover, the gap formed between adjacent convex parts can make the air pressure at the runaway place consistent with that of the explosion-proof valve, enabling the explosion-proof valve to spray smoothly and avoiding cracking of the weld between the end cover and the housing.

[0029] The second aspect of the present application provides a battery device, which includes a box body and a plurality of battery cells. The plurality of battery cells are accommodated in the box body, and the battery cells are the battery cells of any one of the above. The battery device has at least the same advantages as the battery cells.

[0030] The third aspect of the present application provides an electrical device, which includes the above-mentioned battery device. The electrical device has at least the same advantages as the battery device.

[0031] The above description is only an overview of the technical solution of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of the present application more obvious and understandable, the specific embodiments of the present application are specifically given below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0033] Figure 1 is a schematic structural diagram of a battery cell provided by an embodiment of the present application;

[0034] Figure 2 is a schematic cross-sectional view of a partial structure of a battery cell provided by an embodiment of the present application;

[0035] Figure 3 is a schematic structural diagram of another embodiment of a convex portion of an end cap provided by an embodiment of the present application;

[0036] Figure 4 is a schematic structural diagram of another embodiment of the assembly between an end cap and a first current collector provided by an embodiment of the present application;

[0037] Figure 5 is a schematic structural diagram of yet another embodiment of the assembly between an end cap and a first current collector provided by an embodiment of the present application;

[0038] Figure 6 is a schematic structural diagram of a battery device provided by an embodiment of the present application;

[0039] Figure 7 is a schematic structural diagram of an electrical device provided by an embodiment of the present application.

[0040] Reference numeral description:

[0041] Battery cell 1, housing 11, end cap 12, cap body 121, convex portion 122, battery cell assembly 13, first current collector 14, disk body 141, convex block 142, sealing nail 15, box body 2, cover plate 201, hollow structure 202, battery device 100, device main body 200, electrical device 1000. Detailed implementation manners

[0042] To make the objectives, technical solutions and effects of the present application clearer and more definite, the following will describe in detail the embodiments of the technical solutions of the present application with reference to the accompanying drawings. The following embodiments are only used to illustrate the technical solutions of the present application more clearly, and thus are only examples and cannot be used to limit the protection scope of the present application.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion.

[0044] In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects, and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity, specific order or primary-secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the term "plurality" means more than two (including two). Similarly, "multiple groups" means more than two groups (including two groups), and "multiple pieces" means more than two pieces (including two pieces), unless otherwise specifically defined.

[0045] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in connection with the embodiments can be included in at least one embodiment of the present application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0046] In the description of the embodiments of the present application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after.

[0047] Quantities, ratios, and other numerical values are presented herein in a range format. It should be understood that such range formats are for convenience and brevity, and should be understood flexibly, including not only the explicitly specified numerical values as range limits, but also all individual numerical values or sub-ranges covered within the said range, as if each numerical value and sub-range were explicitly specified.

[0048] Currently, cylindrical batteries are a commonly used type of battery. The outer shells of cylindrical batteries are mainly of two types: nickel-plated steel shells and polymers. A cylindrical battery generally includes a housing and an end cap. The housing and the end cap cooperate to form the outer shell of the cylindrical battery. The cylindrical battery also includes an electric core. After the electric core is installed in the housing, it is encapsulated with the end cap to maintain the sealing and reliability of the outer shell structure.

[0049] The connection between the housing and the end cap is usually achieved by welding (for example, laser welding). Among them, the end cap is provided to include a cap body and a convex portion protruding toward the electric core assembly side. The convex portion is provided at the edge of the cap body. The convex portion can be used to block the laser when welding the cap body and the housing, reducing the risk of the structural components (for example, the electric core assembly) inside the housing being burned during the welding process between the housing and the end cap.

[0050] However, during the assembly of cylindrical batteries, the edge of the first current collector plate disposed between the end cap and the battery cell assembly is squeezed by the convex portion of the end cap. There is no supporting force from the end cap in the middle of the first current collector plate, and the first current collector plate tends to deform. The edge of the first current collector plate deforms and bends towards the battery cell assembly relative to the center of the first current collector plate, making the edge of the first current collector plate non-planar, resulting in a gap between the convex portion of the end cap and the edge of the first current collector plate, causing problems such as poor soldering or soldering through between the convex portion of the end cap and the first current collector plate.

[0051] In view of this, the embodiments of the present application provide a battery cell, a battery device, and an electrical device to reduce the gap between the end cap and the first current collector plate. By setting the edge of the first current collector plate to deform and bend towards the battery cell assembly relative to the center of the first current collector plate, and at the same time, the surface of the convex portion close to the first current collector plate is arranged in contact with a part of the surface of the first current collector plate close to the convex portion, the gap between the convex portion and the first current collector plate caused by the deformation and bending of the edge of the first current collector plate towards the battery cell assembly relative to the center of the first current collector plate is reduced, making it not easy to have problems such as poor soldering or soldering through during the welding process between the convex portion of the end cap and the first current collector plate, and improving the connection stability between the convex portion of the end cap and the first current collector plate.

[0052] Please refer to Figures 1 to 3 , Figure 1 which is a schematic structural diagram of the battery cell provided by the embodiments of the present application, Figure 2 which is a schematic cross-sectional view of a partial structure of the battery cell provided by the embodiments of the present application, Figure 3 which is a schematic structural diagram of another embodiment of the convex portion of the end cap provided by the embodiments of the present application.

[0053] The battery cell 1 includes a housing 11, an end cap 12, a battery cell assembly 13, and a first current collector plate 14. The housing 11 has an opening. The battery cell assembly 13 is disposed inside the housing 11. The end cap 12 covers the opening; the end cap 12 includes a cap body 121 and a convex portion 122 protruding towards the battery cell assembly 13, and the convex portion 122 is disposed adjacent to the edge of the cap body 121. The first current collector plate 14 is disposed between the end cap 12 and the battery cell assembly 13; the surface of the convex portion 122 close to the first current collector plate 14 is arranged in contact with a part of the surface of the first current collector plate 14 close to the convex portion 122; the edge of the first current collector plate 14 deforms and bends towards the battery cell assembly 13 relative to the center of the first current collector plate 14.

[0054] The housing 11 encloses to form a receiving space, and the housing 11 can provide mechanical support and physical protection for various components accommodated inside the housing 11. In one embodiment, the housing 11 includes an annular side wall and an end wall. The annular side wall is disposed around the entire peripheral edge of the end wall, and the annular side wall is fixedly connected to the end wall. The end cap 12 is provided at one end of the annular side wall facing away from the end wall. Optionally, the end wall and the annular side wall are integrally formed, that is, the end wall and the annular side wall are formed simultaneously through one processing, which is beneficial to reducing the assembly complexity. In one embodiment, the battery cell 1 further includes a lid. The housing 11 is an annular side wall, and the end cap 12 and the lid are disposed on opposite sides of the housing 11, and the lid is fixedly connected to the annular side wall. It should be noted that the structure of the lid and the structure of the end cap 12 can be the same or different, and are specifically designed according to needs. In one embodiment, the housing 11 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 11 can be determined according to the specific shape and size of the cell assembly 13. Exemplarily, the shape of the housing 11 is cylindrical. In one embodiment, the material of the housing 11 can be various, including but not limited to copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0055] The end cap 12 is covered on one end of the housing 11 to realize the sealing of the end of the housing 11. The end cap 12 can play a role in positioning and fixing various components inside the housing 11, and reduce the shaking or movement of each component inside the housing 11. The end cap 12 can also be used to connect to an external circuit and provide specific functional interfaces. In one embodiment, the shape and size of the end cap 12 are set in cooperation with the shape and size of the housing 11. Exemplarily, the housing 11 is cylindrical, the overall contour of the end cap 12 is circular, and the battery cell 1 is cylindrical. In one embodiment, the material of the end cap 12 can be various, including but not limited to copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0056] The battery cell assembly 13 is a component in the battery cell 1 where electrochemical reactions occur. The battery cell assembly 13 may include a battery cell body, a positive electrode tab, and a negative electrode tab. The battery cell assembly 13 is mainly formed by winding or laminating a positive electrode sheet and a negative electrode sheet, and usually, a separator is provided between the positive electrode sheet and the negative electrode sheet. As an example, the separator can be a diaphragm, and the material of the diaphragm can be PP (polypropylene) or PE (polyethylene), etc. As an example, the positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer, and the positive electrode active material layer is coated on the surface of the positive electrode current collector. The current collector without the positive electrode active material layer coated serves as the positive electrode tab. As an example, the negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer, and the negative electrode active material layer is coated on the surface of the negative electrode current collector. The current collector without the negative electrode active material layer coated serves as the negative electrode tab. As an example, the material of the positive electrode current collector can be aluminum, and the positive electrode active material can be lithium cobaltate, lithium iron phosphate, ternary lithium, or lithium manganate, etc.; the material of the negative electrode current collector can be copper, and the negative electrode active material can be carbon or silicon, etc.

[0057] The first current collector plate 14 is connected to the positive electrode tab or the negative electrode tab of the battery cell assembly 13, and can effectively collect the current on the positive electrode tab or the negative electrode tab and conduct it to the external circuit. The first current collector plate 14 can provide fixation and support for the tab connected to it, reduce the shaking or displacement of the tab inside the battery, and reduce problems such as poor contact or short circuit caused by the movement of the tab.

[0058] In the embodiment of the present application, the end cover 12 is provided to include a cover body 121 and a convex portion 122 protruding toward the battery cell assembly 13. The end cover 12 is covered on the end of the housing 11. The surface of the convex portion 122 of the end cover 12 close to the first current collector plate 14 is attached to a part of the surface of the first current collector plate 14 close to the convex portion 122. The convex portion 122 of the end cover 12 contacts and presses the edge of the first current collector plate 14, and the edge of the first current collector plate 14 deforms and bends in the direction close to the battery cell assembly 13 relative to the center of the first current collector plate 14; since the surface of the convex portion 122 close to the first current collector plate 14 is attached to a part of the surface of the first current collector plate 14 close to the convex portion 122, the gap between the convex portion 122 of the end cover 12 and the first current collector plate 14 caused by the deformation and bending of the edge of the first current collector plate 14 in the direction close to the battery cell assembly 13 relative to the center of the first current collector plate 14 is reduced, making it not easy to have problems such as virtual soldering or soldering through during the welding process between the convex portion 122 of the end cover 12 and the first current collector plate 14, and improving the connection stability between the convex portion 122 of the end cover 12 and the first current collector plate 14.

[0059] In one embodiment, as Figure 2 、 Figure 3 shown, the surface of the convex portion 122 close to the first current collector plate 14 is an inclined surface.

[0060] The surface of the convex portion 122 close to the first current collector plate 14 being an inclined surface means that the surface of the convex portion 122 close to the first current collector plate 14 is inclined relative to the cover body 121 towards the surface close to the first current collector plate 14.

[0061] By setting the surface of the convex portion 122 close to the first current collector plate 14 as an inclined surface, the deformation and bending of the edge of the first current collector plate 14 are matched with the surface of the convex portion 122 close to the first current collector plate 14, and the surface of the convex portion 122 close to the first current collector plate 14 is arranged to be in contact with the part of the surface of the first current collector plate 14 close to the convex portion 122, which is beneficial to reducing the gap between the convex portion 122 and the first current collector plate 14 and maintaining the connection stability between the convex portion 122 of the end cover 12 and the first current collector plate 14. It can be understood that compared with setting the surface of the edge of the thinner first current collector plate 14 as an inclined surface, setting the surface of the convex portion 122 of the end cover 12 close to the first current collector plate 14 as an inclined surface has a simpler processing technology and is beneficial to reducing costs.

[0062] Optionally, when the first current collector plate 14 is in a flat state, the surface of the part of the first current collector plate 14 configured to be in contact with the convex portion 122 is a plane; in this case, the surface of the convex portion 122 close to the first current collector plate 14 is an inclined surface. During the process of installing the end cover 12 into the housing 11, the convex portion 122 presses the edge of the first current collector plate 14, causing the edge of the first current collector plate 14 to bend to form an inclined surface, and the inclined surface of the convex portion 122 close to the first current collector plate 14 is in contact with the inclined surface formed by the bending of the edge of the first current collector plate 14. It should be noted that when the first current collector plate 14 is in a flat state, it can be that after the end cover 12 is separated from the housing 11, the deformation and bending of the edge of the first current collector plate 14 automatically return to the flat state, or the deformation and bending of the edge of the first current collector plate 14 return to the flat state under the action of an external force; when the first current collector plate 14 is in a flat state, the surface of the part of the first current collector plate 14 configured to be in contact with the convex portion 122 (i.e., the surface of the edge of the first current collector plate 14) is a plane, and this plane is parallel to the cover body 121. For the case where the surface of the convex portion 122 close to the first current collector plate 14 is an inclined surface, the surface of the first current collector plate 14 close to the end cover 12 can be a plane. For example, before being installed into the housing 11, the first current collector plate 14 is a flat circular metal sheet with a uniform thickness.

[0063] In an embodiment, the surface of the convex portion 122 close to the first current collector plate 14 is an inclined plane or an arc surface. Optionally, as Figure 2 shown, the surface of the convex portion 122 close to the first current collector plate 14 is an inclined plane. Optionally, as Figure 3 shown, the surface of the convex portion 122 close to the first current collector plate 14 is an inclined arc surface.

[0064] By setting the surface of the convex portion 122 close to the first current collector plate 14 to be a flat surface or an arc surface, the surface of the convex portion 122 close to the first current collector plate 14 is matched with the deformation and bending of the edge of the first current collector plate 14, and the surface of the convex portion 122 close to the first current collector plate 14 is arranged to fit with the part of the surface of the first current collector plate 14 close to the convex portion 122, which is beneficial to reducing the gap between the convex portion 122 and the first current collector plate 14 and maintaining the connection stability between the convex portion 122 of the end cover 12 and the first current collector plate 14.

[0065] In one embodiment, as Figure 2 shown, the surface of the convex portion 122 close to the first current collector plate 14 is an inclined flat surface, and the acute angle α formed between the surface of the convex portion 122 close to the first current collector plate 14 and the cover body 121 is 3°-7°.

[0066] The overall contour of the cover body 121 is a flat plate structure. The surface of the part of the cover body 121 adjacent to the convex portion 122 close to the first current collector plate 14 is a flat surface; optionally, the surface of the part of the cover body 121 adjacent to the convex portion 122 close to the first current collector plate 14 is a horizontal surface, which is perpendicular to the direction in which the end cover 12 covers the end of the housing 11. The angle formed between the surface of the convex portion 122 close to the first current collector plate 14 and the cover body 121 is the angle formed between the surface of the convex portion 122 close to the first current collector plate 14 and the surface of the part of the cover body 121 adjacent to the convex portion 122 close to the first current collector plate 14.

[0067] Exemplarily, the acute angle formed between the surface of the convex portion 122 close to the first current collector plate 14 and the cover body 121 can be 3°, 4°, 5°, 6°, 7°, etc., or a range composed of any two of the above values, for example, 4°-6°, 5°-7°, etc.

[0068] By making the above settings for the inclined surface of the convex portion 122 close to the first current collector plate 14, the surface of the convex portion 122 close to the first current collector plate 14 is matched with the deformation and bending of the edge of the first current collector plate 14, and the tightness of the fit between the surface of the convex portion 122 close to the first current collector plate 14 and the part of the surface of the first current collector plate 14 close to the convex portion 122 is maintained, which is beneficial to reducing the gap between the convex portion 122 and the first current collector plate 14 and maintaining the connection stability between the convex portion 122 of the end cover 12 and the first current collector plate 14.

[0069] In one embodiment, as Figure 3 shown, the surface of the convex portion 122 close to the first current collector plate 14 is an inclined concave arc surface.

[0070] The concave arc surface is such that the center of curvature of the concave arc surface is located on the concave side of the arc surface, and the arc surface bends towards the direction close to the cover body 121 to form a concave arc surface.

[0071] By setting the surface of the convex portion 122 close to the first current collector plate 14 as an inclined concave arc surface, the shape of the surface of the convex portion 122 close to the first current collector plate 14 is matched with the deformed and bent shape of the edge of the first current collector plate 14, maintaining the tightness between the surface of the convex portion 122 close to the first current collector plate 14 and the partial surface of the first current collector plate 14 close to the convex portion 122, which is beneficial to reducing the gap between the convex portion 122 and the first current collector plate 14 and maintaining the connection stability between the convex portion 122 of the end cap 12 and the first current collector plate 14.

[0072] In an embodiment, the convex portion 122 is spaced from the edge of the cover body 121, and the edge of the cover body 121 is fixedly connected to the housing 11; along the radial direction from the center to the edge of the end cap 12, the height of the convex portion 122 gradually increases.

[0073] The fact that the convex portion 122 is spaced from the edge of the cover body 121 can be understood as: the cover body 121 includes a first portion and a second portion located on opposite sides of the convex portion 122, the first portion is located inside the convex portion 122, and the second portion is located outside the convex portion 122, wherein the inside of the convex portion 122 is the side of the convex portion 122 close to the center of the cover body 121; the second portion of the cover body 121 is fixedly connected to the housing 11. Optionally, the edge of the cover body 121 (i.e., the second portion of the cover body 121) is fixedly connected to the housing 11 by welding; the height of the convex portion 122 is higher than the thickness of the edge of the cover body 121, and the convex portion 122 can prevent the influence on the internal components of the housing 11 during the welding of the cover body 121 and the housing 11, reducing the risk of the internal components of the housing 11 being burned.

[0074] The height of the convex portion 122 refers to the dimension of the convex portion 122 along the direction from the cover body 121 pointing to the first current collector plate 14. In other words, the height of the convex portion 122 refers to the dimension of the convex portion 122 in the direction perpendicular to the cover body 121.

[0075] By setting that along the radial direction from the center to the edge of the end cap 12, the height of the convex portion 122 gradually increases, the increased part of the height of the convex portion 122 fills the space formed by the deformed and bent edge of the first current collector plate 14, and the surface of the convex portion 122 close to the first current collector plate 14 is in close fit with the partial surface of the first current collector plate 14 close to the convex portion 122, which is beneficial to reducing the gap between the convex portion 122 and the first current collector plate 14 and maintaining the connection stability between the convex portion 122 of the end cap 12 and the first current collector plate 14.

[0076] Optionally, the edge of the cover body 121 is welded to the housing 11.

[0077] In one embodiment, the height of the outer edge of the surface of the convex portion 122 close to the first current collector plate 14 relative to the edge of the cover body 121 is a first value; when the first current collector plate 14 is in a flat state, the surface of the portion of the first current collector plate 14 configured to contact the convex portion 122 is a plane, and the distance between the surface of the first current collector plate 14 facing away from the battery cell assembly 13 and the end face of the housing 11 is a second value; the first value is greater than the second value.

[0078] The outer edge of the surface of the convex portion 122 close to the first current collector plate 14 refers to the edge of the surface of the convex portion 122 close to the first current collector plate 14 that is far from the center of the cover body 121.

[0079] The height of the outer edge of the surface of the convex portion 122 close to the first current collector plate 14 relative to the edge of the cover body 121 means: along the axial direction of the battery cell 1, the distance between the outer edge of the surface of the convex portion 122 close to the first current collector plate 14 and the surface of the portion of the cover body 121 located outside the convex portion 122 close to the first current collector plate 14.

[0080] When the first current collector plate 14 is in a flat state, it can be that after the end cover 12 is separated from the housing 11, the deformation and bending of the edge of the first current collector plate 14 automatically recover to the flat state, or the deformation and bending of the edge of the first current collector plate 14 recover to the flat state under the action of an external force. When the first current collector plate 14 is in a flat state, the surface of the portion of the first current collector plate 14 configured to contact the convex portion 122 is a plane, and this plane is parallel to the cover body 121.

[0081] The distance between the surface of the first current collector plate 14 facing away from the battery cell assembly 13 and the end face of the housing 11 is the distance along the axial direction of the battery cell 1 between the surface of the first current collector plate 14 facing away from the battery cell assembly 13 and the end face of the end of the housing 11 close to the cover body 121.

[0082] By setting the first value to be greater than the second value, after the battery cell assembly 13 and the first current collector plate 14 are assembled in the housing 11, the assembly space left in the housing 11 is in interference fit with the end cover 12, maintaining the fixation of the positions of the structural components in the housing 11 and reducing the shaking and displacement of the structural components in the housing 11. Since there is a certain interference amount during the assembly of the end cover 12 and the housing 11, the edge of the first current collector plate 14 is squeezed by the convex portion 122 of the end cover 12, and the edge of the first current collector plate 14 bends and deforms in the direction close to the battery cell assembly 13. Even if the edge of the first current collector plate 14 bends and deforms, the deformed edge of the first current collector plate 14 is arranged in close fit with the surface of the convex portion 122 close to the first current collector plate 14, reducing the gap between the convex portion 122 and the first current collector plate 14 and maintaining the connection stability between the convex portion 122 of the end cover 12 and the first current collector plate 14.

[0083] In one embodiment, the difference between the first value and the second value is 0.2 mm - 0.4 mm.

[0084] The difference between the first value and the second value can be 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, etc., or it can be a range composed of any two of the above values. For example, 0.2 mm - 0.3 mm, 0.3 mm - 0.4 mm, etc.

[0085] By designing the difference between the first value and the second value as described above, the interference fit during the assembly of the end cover 12 and the housing 11 is more appropriate, and the bending deformation of the edge of the first current collector plate 14 is smaller. By setting the surface of the convex portion 122 close to the first current collector plate 14 as an inclined surface, the surface of the convex portion 122 close to the first current collector plate 14 can be arranged to fit with a part of the surface of the first current collector plate 14 close to the convex portion 122, reducing the gap between the convex portion 122 and the first current collector plate 14 and maintaining the connection stability between the convex portion 122 of the end cover 12 and the first current collector plate 14.

[0086] It should be noted that when the difference between the first value and the second value is 0.2 mm - 0.4 mm, the interference fit during the assembly of the end cover 12 and the housing 11 is more appropriate, the bending deformation of the edge of the first current collector plate 14 is smaller, the surface of the convex portion 122 close to the first current collector plate 14 is an inclined plane, and the acute angle formed between the surface of the convex portion 122 close to the first current collector plate 14 and the cover body 121 is set to 3° - 7°, so that the surface of the convex portion 122 close to the first current collector plate 14 fits well with a part of the surface of the first current collector plate 14 close to the convex portion 122, reducing the gap between the convex portion 122 and the first current collector plate 14 and maintaining the connection stability between the convex portion 122 of the end cover 12 and the first current collector plate 14.

[0087] In one embodiment, as Figure 4 shown, Figure 4 is a schematic structural diagram of another embodiment of the assembly between the end cover and the first current collector plate provided by the embodiment of the present application; the first current collector plate 14 includes a plate body 141 and a convex block 142 provided on the surface of the plate body 141 close to the convex portion 122. The surface of the convex block 142 close to the convex portion 122 is arranged to fit with the surface of the convex portion 122 close to the convex block 142, and the surface of the convex block 142 close to the convex portion 122 is an inclined surface.

[0088] The surface of the bump 142 close to the convex portion 122 being an inclined surface means that the surface of the bump 142 close to the convex portion 122 is inclined relative to the disk body 141 towards the surface close to the convex portion 122 (before bending). Optionally, along the radial direction from the center to the edge of the first current collector disk 14, the height of the bump 142 gradually increases; wherein, the height of the bump 142 refers to the dimension of the bump 142 in the direction perpendicular to the first current collector disk 14. After the edge of the first current collector disk 14 is bent, the surface of the bump 142 close to the convex portion 122 can be parallel to the cover body 121. Optionally, the disk body 141 and the bump 142 can be integrally formed.

[0089] By setting the surface of the bump 142 close to the convex portion 122 as an inclined surface, after the edge of the first current collector disk 14 is bent and deformed, the bump 142 of the first current collector disk 14 can achieve good fitting with the convex portion 122 of the end cover 12, which is beneficial to reducing the gap between the convex portion 122 and the bump 142 of the first current collector disk 14 and maintaining the connection stability between the convex portion 122 of the end cover 12 and the first current collector disk 14.

[0090] Optionally, the surface of the convex portion 122 close to the first current collector disk 14 is a plane, which is parallel to the cover body 121, and the surface of the convex portion 122 close to the first current collector disk 14 fits with the surface of the bump 142 close to the convex portion 122.

[0091] Optionally, the surface of the convex portion 122 close to the first current collector disk 14 is a plane, and the surface of the bump 142 close to the convex portion 122 is an inclined plane to cooperate with the surface of the convex portion 122 close to the first current collector disk 14, so as to maintain good fitting between the bump 142 of the first current collector disk 14 and the convex portion 122 of the end cover 12.

[0092] In an embodiment, as Figure 5 shown, Figure 5 is a schematic structural diagram of another embodiment of the assembly between the end cover and the first current collector disk provided by the embodiment of the present application; the first current collector disk 14 includes a disk body 141 and a bump 142 provided on the surface of the disk body 141 close to the convex portion 122, and the surface of the bump 142 close to the convex portion 122 is an inclined surface (before the edge of the first current collector disk 14 is bent); the surface of the convex portion 122 close to the first current collector disk 14 is an inclined surface; the surface of the bump 142 close to the convex portion 122 and the surface of the convex portion 122 close to the bump 142 are arranged in a fitting manner.

[0093] By making the above settings for the convex portion 122 and the bump 142, the surface of the bump 142 close to the convex portion 122 and the surface of the convex portion 122 close to the bump 142 are arranged in a fitting manner, reducing the gap between the convex portion 122 and the bump 142 of the first current collector disk 14, and maintaining the connection stability between the convex portion 122 of the end cover 12 and the first current collector disk 14.

[0094] In one embodiment, along the radial direction of the battery cell 1, the width of the convex portion 122 is 2 mm - 4 mm.

[0095] The radial direction of the battery cell 1 refers to the direction from the center of the battery cell 1 towards the edge of the battery cell 1. The width of the convex portion 122 can be 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, etc., or it can also be a range composed of any two of the above values. For example, 2 mm - 3 mm, 3 mm - 4 mm, etc.

[0096] By setting the width of the convex portion 122 as described above, the stability of the connection between the convex portion 122 and the first current collector plate 14 is maintained, the swaying or movement of the first current collector plate 14 within the housing 11 is reduced, and further, the ear tabs connected to the first current collector plate 14 are less likely to sway or shift inside the battery, reducing problems such as poor contact or short circuit caused by the movement of the ear tabs.

[0097] In one embodiment, the surface of the convex portion 122 close to the first current collector plate 14 is welded to the surface of the first current collector plate 14 close to the convex portion 122.

[0098] By setting the welding between the surface of the convex portion 122 close to the first current collector plate 14 and the surface of the first current collector plate 14 close to the convex portion 122, the stability and relatively high connection strength of the connection between the convex portion 122 and the first current collector plate 14 are maintained. At the same time, the surface of the convex portion 122 close to the first current collector plate 14 is arranged in a fitting manner with a partial surface of the first current collector plate 14 close to the convex portion 122. Welding between the convex portion 122 and the first current collector plate 14 can reduce the risk of false welding or burn-through during welding.

[0099] Optionally, laser penetration welding is used outside the end cap 12 to weld the convex portion 122 of the end cap 12 to the first current collector plate 14.

[0100] In one embodiment, as Figure 1 shown, the end cap 12 includes a plurality of convex portions 122, and the plurality of convex portions 122 are arranged at intervals along the circumferential direction of the cover body 121.

[0101] By arranging the plurality of convex portions 122 at intervals along the circumferential direction of the cover body 121, a gap is formed between adjacent convex portions 122, and this gap can be used for gas conduction. When a thermal runaway state occurs inside the battery cell assembly 13, if the runaway point is close to the edge of the end cap 12, the gap formed between adjacent convex portions 122 can make the air pressure at the runaway location consistent with that of the explosion-proof valve, enabling the explosion-proof valve to spray smoothly and preventing the weld seam between the end cap 12 and the housing 11 from cracking.

[0102] In one embodiment, at a position corresponding to the convex portion 122 on the end cap 12, a first concave portion is formed that depresses from the outer surface of the cover body 121 towards the battery cell assembly 13. The first concave portion is used to release stress when welding the cover body 121 to the housing 11.

[0103] In one embodiment, the battery cell 1 further includes a second current collector plate, and the second current collector plate and the first current collector plate 14 are located on opposite sides of the battery cell assembly 13. Optionally, one of the first current collector plate 14 and the second current collector plate is an aluminum current collector plate, and the other is a copper current collector plate; the aluminum current collector plate is welded to the cathode tab of the battery cell assembly 13, and the copper current collector plate is welded to the anode tab of the battery cell assembly 13.

[0104] In one embodiment, as Figure 1 shown, the battery cell 1 further includes a sealing nail 15, the sealing nail 15 is arranged at the end of the housing 11, and the sealing nail 15 and the end cover 12 are located on opposite sides of the battery cell assembly 13. When the internal pressure of the battery cell 1 reaches a certain value, the sealing nail will be first opened to release the internal pressure, thereby reducing serious safety accidents such as battery explosion and playing a role in protecting the battery and the safety of the user.

[0105] Please refer to Figure 6 , Figure 6 which is a schematic structural diagram of the battery device provided by the embodiment of the present application.

[0106] The battery device 100 includes a box body 2 and a plurality of battery cells 1, and the battery cells 1 are accommodated in the box body 2.

[0107] Among them, the box body 2 is used to provide a accommodation space for the battery cells 1, and the box body 2 can encapsulate one or more battery cells 1. The box body 2 can adopt various structures including but not limited to, for example, the box body 2 can include a cover plate 201 and a hollow structure 202 with one end open, wherein the cover plate 201 covers the opening side of the hollow structure 202 to jointly define the accommodation space. Of course, the box body 2 can be in various shapes, such as a cylinder, a cuboid, etc.

[0108] The battery cell 1 is the battery cell 1 provided by the above embodiment, and for the specific structure, please refer to the above embodiment and will not be elaborated here. There can be multiple battery cells 1, and the multiple battery cells 1 can be connected in series, in parallel or in a hybrid connection. A hybrid connection means that there are both series and parallel connections among the multiple battery cells 1. The multiple battery cells 1 can be directly connected in series, in parallel or in a hybrid connection together, and then the whole formed by the multiple battery cells 1 is accommodated in the box body 2; of course, the battery device 100 can also be that multiple battery cells 1 are first connected in series, in parallel or in a hybrid connection to form a battery device 100 module form, and then multiple battery device 100 modules are connected in series, in parallel or in a hybrid connection to form a whole and are accommodated in the box body 2. The battery device 100 can also include other structures. For example, the battery device 100 can also include a busbar component for realizing the electrical connection among the multiple battery cells 1.

[0109] Please refer to Figure 7 , Figure 7It is a schematic structural diagram of an electrical device provided by an embodiment of the present application.

[0110] The electrical device 1000 may include a device main body 200 and a battery device 100, and the battery device 100 is arranged on the device main body 200. The battery device 100 is used to supply power to the electrical components of the device main body 200 so that the device main body 200 can operate.

[0111] The electrical components can be elements that can consume electricity; for example, the electrical components can be a controller and electronic components, etc. The controller can be a central processing unit (Central Processing Unit, abbreviated as CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0112] The electrical device 1000 can be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, and an electric tool, etc. The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. The spacecraft includes an airplane, a rocket, a space shuttle and a spaceship, etc. The electric toy includes a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy and an electric airplane toy, etc.; the electric tool includes a metal cutting electric tool, a grinding electric tool, an assembly electric tool and a railway electric tool, for example, an electric drill, an electric grinding wheel, an electric wrench, an electric screwdriver, a hammer drill, an impact drill, a concrete vibrator and a power planer, etc. For the convenience of description in the following embodiments, the electrical device 1000 is taken as an example of a vehicle for description.

[0113] In some examples, the electrical device 1000 can be a vehicle, the device main body 200 can be a vehicle frame, and the battery device 100 is installed on the vehicle frame. The electrical components can be the lights of the vehicle (such as front lights, rear lights, etc.), a display screen, an instrument panel, a control system (such as a controller), etc. The electrical components are installed on the vehicle body.

[0114] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be covered within the scope of the claims and the specification of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: a housing having an opening; A battery cell assembly is disposed in the housing; An end cover, which is disposed on the opening; the end cover comprises a cover body and a convex portion protruding toward one side of the battery cell assembly; the convex portion is disposed adjacent to an edge of the cover body; A first current collecting disk is arranged between the end cover and the battery cell assembly; a surface of the protrusion close to the first current collecting disk is fitted with a partial surface of the first current collecting disk close to the protrusion; an edge of the first current collecting disk is deformed and bent relative to the center of the first current collecting disk toward the direction close to the battery cell assembly.

2. The battery cell according to claim 1, characterized in that: A surface of the protrusion close to the first current collecting plate is an inclined surface.

3. The battery cell according to claim 2, characterized in that: The surface of the convex portion close to the first current collecting plate is an inclined plane or a curved surface.

4. The battery cell according to claim 3, characterized in that: The surface of the convex portion close to the first current collecting plate is an inclined plane, and the acute angle formed between the surface of the convex portion close to the first current collecting plate and the cover body is 3°-7°.

5. The battery cell according to claim 3, characterized in that: The surface of the convex portion close to the first current collecting plate is an inclined concave arc surface.

6. The battery cell according to claim 2, characterized in that: The convex portion is spaced apart from the edge of the cover body, and the edge of the cover body is fixedly connected to the shell; along the radial direction from the center to the edge of the end cover, the height of the convex portion gradually increases.

7. The battery cell according to claim 6, characterized in that: The height of the outer edge of the surface of the convex portion close to the first current collecting plate relative to the edge of the cover body is a first value; the first current collecting plate is in a flat state, the surface of the portion of the first current collecting plate configured to contact the convex portion is a plane, and the distance between the surface of the first current collecting plate away from the battery cell assembly and the end surface of the shell is a second value; The first value is greater than the second value.

8. The battery cell according to claim 7, characterized in that: The difference between the first value and the second value is 0.2 mm-0.4 mm.

9. The battery cell according to claim 1, characterized in that: The first current collecting disk includes a disk body and a bump provided on the disk body near the convex portion surface, the bump near the convex portion surface is fitted with the convex portion near the bump surface, and the bump near the convex portion surface is an inclined surface.

10. The battery cell according to claim 1, characterized in that: Along the radial direction of the battery cell, the width of the protrusion is 2 mm-4 mm.

11. The battery cell according to claim 1, characterized in that: A surface of the protrusion close to the first current collecting plate is welded to a surface of the first current collecting plate close to the protrusion.

12. The battery cell according to claim 1, characterized in that: The end cover includes a plurality of protrusions, and the plurality of protrusions are arranged at intervals along the circumferential direction of the cover body.

13. A battery device, characterized in that: include: Box; A plurality of battery cells are housed in the box; the battery cells are the battery cells according to any one of claims 1 to 12.

14. An electrical device, characterized in that: A battery cell comprising any one of claims 1 to 12 or a battery device comprising claim 13.

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