Battery cell, battery, and electric device

Abstract

Embodiments of the present application provide a battery cell, a battery, and an electric device. The battery cell comprises a casing, an electrode assembly, an electrode terminal, and a connecting member; the casing comprises a first wall; the electrode assembly is arranged in the casing, and the electrode assembly comprises a tab; the electrode terminal is arranged on the first wall, and the electrode terminal is electrically connected to the tab; the connecting member is at least partially arranged on the periphery of the electrode terminal, and the connecting member is configured to fix the electrode terminal to the first wall. The connecting member is connected to the first wall, and the connecting member comprises a first sub-component and a second sub-component connected to each other. The first sub-component is connected to the first wall, and the hardness of the second sub-component is greater than that of the first sub-component. The technical solution of the present application can improve the reliability of the battery cell.

Description

Battery cell, battery and electric device TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a battery cell, a battery and an electric device. BACKGROUND

[0002] Energy saving and emission reduction is the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their energy saving and environmental protection advantages. For electric vehicles, battery technology is an important factor for their development.

[0003] In the manufacturing process of the battery, the reliability of the battery is a problem that cannot be ignored. Therefore, how to improve the reliability of the battery is a technical problem that needs to be solved in the battery technology.

[0004] SUMMARY

[0005] The present application provides a battery cell, a battery and an electric device, which can improve the reliability of the battery cell.

[0006] The present application is achieved by the following technical solutions:

[0007] In a first aspect, the present application provides a battery cell, which comprises a shell, an electrode assembly, an electrode terminal and a connecting piece. The shell comprises a first wall; the electrode assembly is arranged in the shell, and the electrode assembly comprises a tab; the electrode terminal is arranged on the first wall, and the electrode terminal is electrically connected with the tab; the connecting piece is at least partially arranged on the outer periphery of the electrode terminal, and the connecting piece is used for fixing the electrode terminal to the first wall. The connecting piece is connected to the first wall, and the connecting piece comprises a first sub-component and a second sub-component connected with each other, the first sub-component is connected with the first wall, and the hardness of the second sub-component is greater than that of the first sub-component.

[0008] According to the battery cell of the present application, the first sub-component and the second sub-component are connected with each other, the hardness of the second sub-component is greater than that of the first sub-component, the overall strength of the connecting piece is improved, the deformation resistance of the connecting piece is improved, the restraining effect of the connecting piece on the electrode terminal is improved, the risk of the electrode terminal moving relative to the first wall is reduced, the connection reliability of the electrode terminal with other components (such as a adapter or a tab) is improved, and the reliability of the battery cell is improved.

[0009] According to some embodiments of the present application, the melting point of the first sub-component is greater than or equal to 500 DEG C and less than or equal to 1000 DEG C, the melting point of the second sub-component is greater than or equal to 1050 DEG C and less than or equal to 3500 DEG C, and the melting point of the first wall is greater than or equal to 500 DEG C and less than or equal to 1000 DEG C.

[0010] In the above scheme, the melting point of the first sub-component is close to or the same as the melting point of the first wall, so as to facilitate welding of the first sub-component and the first wall, and the melting point of the second sub-component is higher, and the second sub-component has better high-temperature resistance and is not easy to be deformed by heat.

[0011] According to some embodiments of the present application, the hardness of the first sub-component is greater than or equal to 30 kgf / mm 2 and less than or equal to 170 kgf / mm 2 ; and the hardness of the second sub-component is greater than or equal to 100 kgf / mm 2 and less than or equal to 500 kgf / mm 2 .

[0012] In the above scheme, the hardness of the first sub-component satisfies the above range, the first sub-component has better deformation resistance, the hardness of the second sub-component satisfies the above range, the second sub-component has better deformation resistance relative to the first sub-component, and the overall deformation resistance of the structure formed by the cooperation of the second sub-component and the first sub-component is better, so as to constrain the electrode terminal from moving relative to the first wall.

[0013] According to some embodiments of the present application, the material of the first sub-component is the same as the material of the first wall.

[0014] In the above scheme, the material of the first sub-component is the same as the material of the first wall, so as to facilitate welding of the first sub-component and the first wall.

[0015] According to some embodiments of the present application, the base metal of the first sub-component is the same as the base metal of the second sub-component.

[0016] In the above scheme, the materials of the first sub-component and the second sub-component are both alloys, the base metal of the first sub-component is the same as the base metal of the second sub-component, so as to facilitate processing and manufacturing.

[0017] According to some embodiments of the present application, the first sub-component is laser welded with the first wall.

[0018] In the above scheme, the first sub-component is laser welded with the first wall, and the welding quality is high, and the deformation of the to-be-welded piece is small.

[0019] According to some embodiments of the present application, the material of the first sub-component includes aluminum or aluminum alloy, and the material of the second sub-component includes steel, stainless steel, copper, copper alloy, titanium or titanium alloy.

[0020] In the above scheme, the steel, stainless steel, copper, copper alloy, titanium or titanium alloy has a higher hardness, so that the connecting piece has a higher overall strength.

[0021] According to some embodiments of the present application, the material of the first sub-component includes steel or stainless steel, and the material of the second sub-component includes titanium or titanium alloy.

[0022] In the above scheme, the material of the first sub-component and the material of the second sub-component satisfy the above condition, the first sub-component and the second sub-component both have high hardness, and the connecting piece has high overall strength.

[0023] According to some embodiments of the present application, the material of the second sub-component comprises ceramic, high-molecular plastic or carbon fiber reinforced composite material.

[0024] In the above scheme, the ceramic, high-molecular plastic or carbon fiber reinforced composite material has high hardness.

[0025] According to some embodiments of the present application, the first sub-component is welded with the first wall to form a first weld, the first sub-component has a first surface facing away from the electrode assembly, and the first weld extends from the first surface to the first wall in the thickness direction of the first wall.

[0026] In the above scheme, the first weld extends to the first wall, and the first weld has a large size so that the first sub-component is firmly connected with the first wall.

[0027] According to some embodiments of the present application, the second sub-component and the electrode terminal at least partially overlap in the same projection plane perpendicular to the thickness direction of the first wall.

[0028] In the above scheme, the second sub-component and the electrode terminal at least partially overlap, and the connecting piece has a better restraining effect on the electrode terminal in the thickness direction of the first wall, so as to facilitate the limitation of the movement of the electrode terminal in the thickness direction of the first wall.

[0029] According to some embodiments of the present application, the first sub-component comprises a first segment and a second segment, the first segment is connected to the first wall, the second segment is located on the inner circumferential side of the first segment, and the second segment is farther away from the electrode assembly than the first wall in the thickness direction of the first wall; and the second segment at least partially overlaps with the second sub-component in the thickness direction of the first wall.

[0030] In the above scheme, the first sub-component is a bent structure, the second segment is farther away from the electrode assembly than the first wall, so as to reasonably utilize the space in the thickness direction of the first wall and facilitate the cooperation between the second segment and the electrode terminal; and the second segment at least partially overlaps with the second sub-component in the thickness direction of the first wall, so that the connecting piece has high hardness at the position corresponding to the second segment, the connecting piece has high anti-deformation ability, and the connecting piece has a higher restraining effect on the electrode terminal.

[0031] According to some embodiments of the present application, the first segment at least partially overlaps with the second sub-component in the thickness direction of the first wall.

[0032] In the above scheme, the first segment also at least partially overlaps the second sub-component, the second sub-component has a larger overlapping area with the first sub-component, which can further improve the overall strength of the connecting piece, improve the deformation resistance of the connecting piece, and improve the constraint effect of the connecting piece on the electrode terminal.

[0033] According to some embodiments of the present application, the first sub-component further comprises a third segment, the first segment connects the first wall through the third segment, the first segment is located on the inner circumferential side of the third segment, along the thickness direction of the first wall, the second segment is farther away from the electrode assembly than the third segment, and the first segment connects the second segment and the third segment.

[0034] In the above scheme, the first segment connects the first wall through the third segment, which facilitates the bending of the first sub-component, facilitates the cooperation of the first sub-component with the first wall and the electrode terminal, and facilitates processing and manufacturing.

[0035] According to some embodiments of the present application, along the thickness direction of the first wall, the third segment at least partially overlaps the second sub-component.

[0036] In the above scheme, the third segment at least partially overlaps the second sub-component, so that the second sub-component has a larger overlapping area with the first sub-component, the connecting piece has higher overall strength, and the constraint effect of the connecting piece on the electrode terminal is improved while the connection firmness of the connecting piece with the first wall is improved.

[0037] According to some embodiments of the present application, the second sub-component comprises a first reinforcing segment stacked with the first segment and a second reinforcing segment stacked with the second segment, and the first reinforcing segment is connected with the second reinforcing segment.

[0038] In the above scheme, the first reinforcing segment is connected with the second reinforcing segment, which can constrain the deformation of the connection between the first segment and the second segment, and reduce the risk of the second segment lifting relative to the first segment.

[0039] According to some embodiments of the present application, the second sub-component further comprises a third reinforcing segment stacked with the third segment, and the third reinforcing segment is connected with the first reinforcing segment.

[0040] In the above scheme, the third reinforcing segment is connected with the first reinforcing segment, which can constrain the deformation of the connection between the first segment and the third segment, and reduce the risk of the first segment lifting relative to the third segment.

[0041] According to some embodiments of the present application, the second sub-component is arranged around the electrode terminal.

[0042] In the above scheme, the second sub-component can be annular, so that the second sub-component is arranged around the electrode terminal, and the second sub-component has a higher constraint effect on the electrode terminal in the circumferential direction thereof.

[0043] According to some embodiments of the present application, the orthographic projection of the first sub-component and the orthographic projection of the second sub-component at least partially overlap on the same projection plane perpendicular to the thickness direction of the first wall.

[0044] In the above scheme, the orthographic projection of the first sub-component and the orthographic projection of the second sub-component at least partially overlap, the second sub-component can strengthen the first sub-component in the thickness direction of the first wall, improve the anti-deformation ability of the first sub-component, so that the connecting piece has higher overall strength, and the movement of the electrode terminal in the thickness direction of the first wall is limited.

[0045] According to some embodiments of the present application, the orthographic projection of the first sub-component and the orthographic projection of the second sub-component completely overlap on the same projection plane perpendicular to the thickness direction of the first wall.

[0046] In the above scheme, the orthographic projection of the first sub-component and the orthographic projection of the second sub-component completely overlap, further strengthening the overall strength of the connecting piece and improving the anti-deformation ability of the connecting piece.

[0047] According to some embodiments of the present application, along the thickness direction of the first wall, the second sub-component is located on the side of the first sub-component facing the electrode assembly.

[0048] In the above scheme, the second sub-component is located on the side of the first sub-component facing the electrode assembly, and since the second sub-component has higher hardness, when the electrode terminal is subjected to a pulling force towards the outside of the battery monomer, the second component exerts a restraining force on the electrode terminal, which has a better restraining effect on the electrode terminal and reduces the risk of movement of the electrode terminal.

[0049] According to some embodiments of the present application, along the thickness direction of the first wall, the second sub-component is located on the side of the first sub-component away from the electrode assembly; the first sub-component and the first wall are connected to form a fixed part, and the second sub-component does not overlap with the fixed part.

[0050] In the above scheme, the second sub-component is located on the side of the first sub-component away from the electrode assembly, and the second sub-component does not overlap with the fixed part, so the second sub-component does not block the connection position of the first sub-component and the first wall, which can facilitate the connection of the first sub-component and the first wall.

[0051] According to some embodiments of the present application, the first sub-component and the second sub-component are both arranged around the electrode terminal.

[0052] In the above scheme, the first sub-component and the second sub-component are both annular, which can exert a restraining force on the electrode terminal at any position in the circumferential direction of the electrode terminal, and has a better restraining effect on the electrode terminal.

[0053] According to some embodiments of the present application, the battery cell further comprises a first insulation member, the first insulation member is at least partially disposed between the electrode terminal and the connecting member; the connecting member has a through hole, a portion of the first insulation member and a portion of the electrode terminal are accommodated in the through hole, and the first insulation member is located between the electrode terminal and the connecting member along a radial direction of the electrode terminal.

[0054] In the above scheme, the first insulation member is at least partially disposed between the electrode terminal and the connecting member, and insulates and separates the electrode terminal and the connecting member, thereby reducing the risk of positive and negative short circuit.

[0055] According to some embodiments of the present application, the first sub-component and the second sub-component are stacked, and the thickness of at least part of the second sub-component is less than the thickness of the first sub-component along the stacking direction.

[0056] In the above scheme, the thickness of at least part of the second sub-component is less than the thickness of the first sub-component along the stacking direction, thereby reducing the overall thickness of the connecting member and reducing the space occupation while improving the overall strength of the connecting member.

[0057] According to some embodiments of the present application, the thickness of the first sub-component is H1, the thickness of the second sub-component is H2, and 0.5≤H1 / (H1+H2)≤0.9 is satisfied.

[0058] In the above scheme, the thickness of the first sub-component and the thickness of the second sub-component satisfy the above relationship, on the one hand, the thickness of the first sub-component is thick, so as to facilitate the welding reliability of the first sub-component and the first wall; on the other hand, the second sub-component has a certain thickness, the second sub-component has high hardness, and the second sub-component has high deformation resistance after being stacked with the first sub-component, and the connecting member can have high overall strength.

[0059] According to some embodiments of the present application, the first sub-component comprises a first main body part and a first connecting part, the first connecting part is annular, the first main body part is connected to the inner circumferential side of the first connecting part, the first connecting part is connected to the first wall, the first main body part at least partially overlaps the second sub-component along the thickness direction of the first wall, and the thickness of the first connecting part is greater than the thickness of the first main body part.

[0060] In the above scheme, the first main body part at least partially overlaps the second sub-component along the thickness direction of the first wall, thereby facilitating the overall strength of the connecting member; the thickness of the first connecting part is greater than the thickness of the first main body part, the first sub-component is locally thickened, thereby facilitating the welding of the first sub-component and the first wall, and improving the connection reliability of the first sub-component and the first wall.

[0061] According to some embodiments of the present application, the width of the first connecting part is greater than or equal to 0.5mm and less than or equal to 3mm along the radial direction of the electrode terminal.

[0062] In the above scheme, the width of the first connecting part satisfies the above relationship, on the one hand, facilitating the welding of the first connecting part and the first wall; on the other hand, the first connecting part occupies a smaller space in the radial direction of the electrode terminal, the size of the second sub-component can be larger, and the connecting piece has higher overall strength.

[0063] According to some embodiments of the present application, the first connecting part is in direct contact with the first wall in the thickness direction of the first wall.

[0064] In the above scheme, the first connecting part is in direct contact with the first wall in the thickness direction of the first wall, facilitating the welding of the first connecting part and the first wall, so that the first connecting part is firmly connected with the first wall.

[0065] According to some embodiments of the present application, a first step surface is formed between the first connecting part and the first main body part, the second sub-component is stacked with the first main body part, and the outer peripheral surface of the second sub-component is fitted with the first step surface.

[0066] In the above scheme, the outer peripheral surface of the second sub-component is fitted with the first step surface, so as to facilitate the assembly of the first sub-component and the second sub-component, and the connecting piece can have higher overall strength.

[0067] According to some embodiments of the present application, at least a part of the second sub-component is located between the first connecting part and the first wall in the thickness direction of the first wall.

[0068] In the above scheme, the second sub-component has higher hardness, at least a part of the second sub-component is located between the first connecting part and the first wall in the thickness direction of the first wall, the connecting piece has higher deformation resistance at the first connecting part, and when the electrode terminal acts on the connecting piece, the connecting piece can have better constraint effect on the electrode terminal, reducing the risk of damage at the connection between the first connecting part and the first wall.

[0069] According to some embodiments of the present application, the second sub-component includes a second main body part and a second connecting part, the thickness of the second main body part is greater than the thickness of the second connecting part; the second connecting part is located between the first connecting part and the first wall in the thickness direction of the first wall; the second main body part is stacked with the first main body part, a first step surface is formed between the first connecting part and the first main body part, a second step surface is formed between the second main body part and the second connecting part, and the second step surface is fitted with the first step surface.

[0070] In the above scheme, the second main body part and the second connecting part are connected with each other, the thickness of the second main body part is greater than the thickness of the second connecting part, so as to facilitate the cooperation of the second connecting part and the first connecting part. The second step surface is fitted with the first step surface, so as to facilitate the fitting of the second sub-component with the first sub-component, so that the connecting piece has higher overall strength.

[0071] According to some embodiments of the present application, along the thickness direction of the first wall, the thickness of the first connecting part is H3, and the thickness of the second connecting part is H4, satisfying 0.5≤H3 / (H3+H4)≤0.9.

[0072] In the above scheme, the thickness of the first connecting part and the thickness of the second connecting part satisfy the above relationship. On the one hand, the thickness of the first connecting part is thick, so as to improve the welding reliability of the first connecting part and the first wall. On the other hand, the second connecting part has a certain thickness, the second connecting part has high hardness, and the second connecting part has high anti-deformation ability after being laminated with the first connecting part. The connecting piece can have high overall strength.

[0073] According to some embodiments of the present application, along the thickness direction of the first wall, the thickness of the first connecting part is H3, satisfying 0.3mm≤H3≤1.5mm.

[0074] In the above scheme, the thickness of the first connecting part satisfies the above relationship. On the one hand, it is convenient for the first connecting part to be welded and connected with the first wall. On the other hand, the first connecting part occupies a smaller space in the thickness direction of the first wall.

[0075] According to some embodiments of the present application, the connecting piece includes a first part and a second part. In the same projection plane perpendicular to the thickness direction of the first wall, the orthographic projection of the first part at least partially overlaps the orthographic projection of the electrode terminal. The second part is connected to the outer circumferential side of the first part. The thickness of the first part is smaller than the thickness of the second part.

[0076] In the above scheme, after the connecting piece is assembled with the electrode terminal, due to the thin thickness of the first part, the structure of the first part after being assembled with the electrode terminal occupies a smaller space in the thickness direction of the first wall, which can reduce the risk of interference between the connecting piece and other components (such as the bus piece, the current collecting member, etc.).

[0077] According to some embodiments of the present application, the first sub-component is welded with the first wall to form a first welding mark. Along the thickness direction of the first wall, the maximum size of the first welding mark is greater than or equal to 0.3mm.

[0078] In the above scheme, the maximum size of the first welding mark in the thickness direction of the first wall is greater than or equal to 0.3mm, so that the first sub-component is firmly welded with the first wall, and the first sub-component has high connection reliability with the first wall.

[0079] According to some embodiments of the present application, the battery monomer further includes a reinforcing piece. The reinforcing piece is fixed to the first wall. The hardness of the reinforcing piece is greater than the hardness of the first wall. Along the thickness direction of the first wall, a part of the electrode terminal is located between the reinforcing piece and the connecting piece.

[0080] In the above scheme, the reinforcing member has high hardness, and in the thickness direction of the first wall, the reinforcing member is clamped with the connecting member to limit the movement of the electrode terminal relative to the first wall.

[0081] According to some embodiments of the present application, the first sub-component is integrally formed with the first wall.

[0082] In the above scheme, the first sub-component is integrally formed with the first wall, which facilitates processing and manufacturing, and makes the first sub-component and the first wall have better connection stability.

[0083] According to some embodiments of the present application, the connecting member is located on the side of the first wall away from the electrode assembly.

[0084] In the above scheme, the connecting member is located on the outer side of the first wall, so as to reduce the risk of interference of the connecting member with the electrode assembly.

[0085] According to some embodiments of the present application, the outer surface of the first wall is provided with a first groove, the bottom wall of the first groove is provided with an electrode lead-out hole, the electrode terminal covers the electrode lead-out hole, at least a part of the connecting member is arranged in the first groove, and the first sub-component is welded with the first wall.

[0086] In the above scheme, the first groove is arranged, which can reduce the space occupation of the connecting member in the thickness direction of the first wall after the connecting member is connected with the first wall.

[0087] In a second aspect, the embodiments of the present application further provide a battery cell.

[0088] In a third aspect, the embodiments of the present application further provide a use-electricity device, which comprises the battery cell or the battery provided according to any of the above embodiments, and the battery cell or the battery is used to provide electric energy.

[0089] Additional aspects and advantages of the present application will be made apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0090] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be regarded as a limitation on the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor.

[0091] FIG. 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application;

[0092] FIG. 2 is a structural exploded schematic diagram of a battery according to some embodiments of the present application;

[0093] Fig. 3 is a structural exploded view of a battery cell according to some embodiments of the present application;

[0094] Fig. 4 is a cross-sectional view of a first wall and an electrode terminal in an assembled state according to some embodiments of the present application;

[0095] Fig. 5 is an enlarged view of a portion A of Fig. 4;

[0096] Fig. 6 is a view of a first sub-component and a first wall in a welded state according to some embodiments of the present application;

[0097] Fig. 7 is an enlarged view of a portion B of Fig. 5;

[0098] Fig. 8 is a view of a second sub-component and the first sub-component in a fitted state according to some embodiments of the present application;

[0099] Fig. 9 is a cross-sectional view of the first sub-component and the second sub-component in an assembled state according to some embodiments of the present application;

[0100] Fig. 10 is an enlarged view of a portion C of Fig. 9;

[0101] Fig. 11 is a cross-sectional view of the first sub-component and the second sub-component in an assembled state according to other embodiments of the present application;

[0102] Fig. 12 is an enlarged view of a portion D of Fig. 11;

[0103] Fig. 13 is a structural view of a connecting member according to some embodiments of the present application;

[0104] Fig. 14 is a structural view of a first wall provided with a reinforcing member according to some embodiments of the present application;

[0105] Fig. 15 is a view of a first sub-component and a first wall in a welded state according to other embodiments of the present application;

[0106] In the drawings, the drawings are not drawn to scale.

[0107] Legend: 100 - battery; 10 - case; 11 - first sub case; 12 - second sub case; 20 - battery cell; 21 - outer shell; 211 - housing; 212 - end cap; 213 - first wall; 2131 - electrode lead-out hole; 2132 - first groove; 22 - electrode assembly; 221 - tab; 23 - electrode terminal; 231 - first body portion; 232 - second body portion; 24 - connector; 24a - first portion; 24b - second portion; 24c - third portion; 241 - first sub member; 241a - first section; 241b - second section; 241c - third section; 241d - first body portion; 241e - first connecting portion; 241f - first step surface; 2411 - first surface; 2412 - second surface; 242 - second sub member; 242a - second body portion; 242b - second connecting portion; 242c - second step surface; 242d - first reinforcing section; 242e - second reinforcing section; 242f - third reinforcing section; 243 - overlapping region; 244 - fixing portion; 245 - through hole; 246 - first solder mark; 25 - first insulating member; 26 - reinforcing member; 27 - sealing member; 28 - second insulating member; 200 - controller; 300 - motor; 1000 - vehicle; Q - central axis of electrode terminal; J - radial direction of electrode terminal; Z - thickness direction of first wall. DETAILED DESCRIPTION

[0108] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings for the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0109] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the specification herein is for describing particular embodiments only and is not intended to be limiting of the application. Unless otherwise defined, all terms used in disclosing the application, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The articles 'a', 'an', and 'the' each followed by'some or more' or 'one or more' of an element are intended to include one or more articles of the described element and do not exclude other integers. The terms "comprise", "comprising", "include", "including", "have" and "having" and any variations thereof are intended to cover a non-exclusive inclusion. The terms "first", "second", and the like specify no order, and do not denote a particular order or precedence.

[0110] Reference to an "embodiment" in this application 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 they necessarily mutually exclusive of one another. As will be apparent to those of ordinary skill in the art, embodiments described in this application can be combined with one another.

[0111] In the description of the application, it is necessary to explain that, unless otherwise explicitly specified and limited, the terms "mount", "connect", "connection", "attach" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those of ordinary skill in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0112] The term "and / or" in this application is only to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in this application generally represents that the front and rear associated objects have an "or" relationship.

[0113] "Multiple" appearing in this application means more than two (including two), and similarly, "multiple groups" means more than two groups (including two groups), and "multiple pieces" means more than two pieces (including two pieces).

[0114] In some embodiments, the battery can be a battery module, and when there are multiple battery monomers, the multiple battery monomers are arranged and fixed to form a battery module.

[0115] In some embodiments, the battery can be a battery pack, and the battery pack includes a box body and a battery monomer, and the battery monomer or the battery module is contained in the box body.

[0116] In some embodiments, the box body can be part of the chassis structure of the vehicle. For example, part of the box body can be at least part of the floor of the vehicle, or part of the box body can be at least part of the cross beam and the longitudinal beam of the vehicle.

[0117] In some embodiments, the battery can be an energy storage device. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0118] In the embodiments of the application, the battery monomer can be a secondary battery, which refers to a battery monomer that can be activated by charging after discharging to continue to use.

[0119] The battery cell can be, but is not limited to, a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead-acid battery, etc.

[0120] The battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During charging and discharging of the battery cell, active ions (e.g., lithium ions) are intercalated and deintercalated between the positive electrode and the negative electrode. The separator is disposed between the positive electrode and the negative electrode, and can function to prevent short circuiting of the positive and negative electrodes while allowing the active ions to pass through.

[0121] In some embodiments, the positive electrode can be a positive electrode sheet, which can include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0122] As an example, the positive electrode current collector has two surfaces opposite in the thickness direction thereof, and the positive electrode active material is disposed on either one or both of the two opposite surfaces of the positive electrode current collector.

[0123] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as the metal foil, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, or titanium, etc. with a silver plating treatment on the surface thereof can be used. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material base material (e.g., a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0124] As an example, the positive electrode active material can include at least one of lithium-containing phosphates, lithium transition metal oxides, and modified compounds thereof. However, the present application is not limited to these materials, and other conventional materials that can be used as a positive electrode active material of a battery can also be used.

[0125] In some embodiments, the negative electrode can be a negative electrode sheet, which can include a negative electrode current collector.

[0126] As an example, the negative electrode current collector can be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver plating treatment on the surface thereof, stainless steel with a silver plating treatment on the surface thereof, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, or titanium, etc. can be used.

[0127] In some embodiments, the negative electrode current collector has two surfaces opposite in the thickness direction thereof, and the negative electrode active material is disposed on either one or both of the two opposite surfaces of the negative electrode current collector.

[0128] As an example, the negative active material can employ a negative active material for a battery that is publicly known in the art. As an example, the negative active material can include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based material, tin-based material, and lithium titanate, etc. The silicon-based material can be selected from at least one of elemental silicon, silicon oxide compound, silicon-carbon composite, silicon-nitrogen composite, and silicon alloy. The tin-based material can be selected from at least one of elemental tin, tin oxide compound, and tin alloy. However, the present application is not limited to these materials, and other conventional materials that can be used as a negative active material for a battery can also be used. These negative active materials can be used alone or in combination of two or more.

[0129] In some embodiments, the separator is a separator film. The type of the separator film is not particularly limited, and any publicly known porous structure separator film having good chemical stability and mechanical stability can be used.

[0130] As an example, the main material of the separator film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride, and ceramic. The separator film can be a single layer film or a multi-layer composite film, and is not particularly limited. In the case of the multi-layer composite film, the materials of the respective layers can be the same or different, and are not particularly limited. The separator can be a separate member located between the positive and negative electrodes, or can be attached to the surface of the positive and negative electrodes.

[0131] In some embodiments, the separator is a solid-state electrolyte. The solid-state electrolyte is disposed between the positive and negative electrodes, and functions to transport ions and separate the positive and negative electrodes.

[0132] In some embodiments, the electrode assembly has a jelly-roll structure. The positive electrode sheet and the negative electrode sheet are wound to have the jelly-roll structure.

[0133] In some embodiments, the electrode assembly has a stack structure.

[0134] In some embodiments, the battery cell can include a case. The case is used to package the electrode assembly and other components such as the electrolyte. The case can be a steel case, an aluminum case, a plastic case (e.g., polypropylene), or a composite metal case (e.g., a copper-aluminum composite case), etc.

[0135] In some embodiments, the case includes a cap and a case body, and the case body is provided with an opening, and the cap closes the opening to form a sealed space for accommodating the electrode assembly and the electrolyte, etc. The case body can be provided with one or more openings. The cap can also be provided with one or more openings.

[0136] In some embodiments, at least one electrode terminal is disposed on the housing, and the electrode terminal is electrically connected with the tab of the electrode assembly. The electrode terminal can be directly connected with the tab, or indirectly connected with the tab through an adapter. The electrode terminal can be disposed on the end cap, or disposed on the housing.

[0137] In some embodiments, an explosion-proof valve is disposed on the housing. The explosion-proof valve is used to release the internal pressure of the battery cell.

[0138] In some embodiments, the housing can be a sealed structure, or a non-sealed structure. As an example, when the housing is a sealed structure, the housing can protect the electrode assembly and prevent electrolyte leakage, etc. When the housing is a non-sealed structure, the housing can protect the electrode assembly, and a sealing bag can be further included between the housing and the electrode assembly, which is used to encapsulate the electrode assembly, electrolyte, etc. Specifically, the sealing bag can be a bag-shaped insulating member or an aluminum plastic film.

[0139] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, or a battery cell with other shapes, including a square battery cell, a blade battery cell, a multi-prismatic battery cell, such as a hexagonal battery cell, etc.

[0140] The development of battery technology needs to consider various design factors, such as energy density, discharge capacity, charge-discharge rate, and other performance parameters, and the reliability of the battery.

[0141] In some embodiments, the battery cell includes a housing, an electrode terminal, and a connecting member. The electrode terminal is disposed on a first wall of the housing, and the connecting member fixes the electrode terminal to the first wall. When the electrode terminal is subjected to an external force, such as a force applied by a busbar (or a tab), the electrode terminal has a tendency to move towards the outside of the battery cell. Due to the low deformation resistance (such as overall strength) of the connecting member, the long-term stress on the electrode terminal can cause the connecting member to deform, resulting in the failure of the connection between the connecting member and the first wall, the movement of the electrode terminal relative to the first wall, and the failure of the connection between the electrode terminal and other components (such as an adapter or a tab), thereby causing the failure of the electrode terminal and reducing the reliability of the battery cell.

[0142] In view of this, the battery cell provided in the embodiments of the present application includes a shell, an electrode assembly, an electrode terminal and a connecting piece. The shell includes a first wall, the electrode assembly is arranged in the shell, and the electrode assembly includes a tab. The electrode terminal is arranged on the first wall, and the electrode terminal is electrically connected with the tab; the connecting piece is arranged at least partially around the electrode terminal, and the connecting piece is used for fixing the electrode terminal to the first wall. The connecting piece is connected to the first wall, and the connecting piece includes a first sub-component and a second sub-component connected with each other, the first sub-component is connected with the first wall, and the hardness of the second sub-component is greater than that of the first sub-component. The connecting piece has a relatively high overall strength, has a good constraint effect on the electrode terminal, and the battery cell has a relatively high reliability.

[0143] In the battery cell, the first sub-component and the second sub-component are connected with each other, the first sub-component is connected with the first wall, and the hardness of the second sub-component is greater than that of the first sub-component. The overall strength of the connecting piece is improved, the deformation resistance of the connecting piece is improved, the constraint effect of the connecting piece on the electrode terminal is improved, the risk of movement of the electrode terminal relative to the first wall is reduced, the connection reliability of the electrode terminal with other components (such as a connecting piece or a tab) is improved, and the reliability of the battery cell is improved.

[0144] The battery disclosed in the embodiments of the present application can be used in, but is not limited to, an electric device such as a vehicle, a ship or an aircraft. The power supply system of the electric device can be composed of the battery disclosed in the present application.

[0145] The embodiments of the present application provide an electric device using a battery as a power supply. The electric device can be, but is not limited to, a mobile phone, a tablet computer, a notebook computer, an electric toy, an electric tool, an electric bicycle, an electric motorcycle, an electric vehicle, a ship, a spacecraft and the like. The electric toy can include a fixed or mobile electric toy, such as a game console, an electric vehicle toy, an electric ship toy and an electric aircraft toy, and the spacecraft can include an airplane, a rocket, a space shuttle and a spacecraft.

[0146] The following embodiments are described by taking a vehicle as an example for the convenience of description.

[0147] Please refer to FIG. 1, which is a structural schematic diagram of a vehicle provided in some embodiments of the present application. The vehicle 1000 can be a fuel automobile, a gas automobile or a new energy automobile, and the new energy automobile can be a pure electric vehicle, a hybrid electric vehicle or a range extended electric vehicle. The vehicle 1000 is internally provided with a battery 100, which can be arranged at the bottom, the head or the tail of the vehicle 1000. The battery 100 can be used for power supply of the vehicle 1000, for example, the battery 100 can be used as an operating power supply of the vehicle 1000, and is used for the circuit system of the vehicle 1000, such as the power demand for starting, navigation and operation of the vehicle 1000.

[0148] The vehicle 1000 can 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 power requirements of the vehicle 1000 during startup, navigation, and driving.

[0149] In some embodiments of the present application, the battery 100 can not only serve as a power source for the operation of the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0150] Referring to FIG. 2, FIG. 2 is a structural exploded view of a battery according to some embodiments of the present application. The battery 100 includes a box body 10 and a battery cell 20, and the battery cell 20 is accommodated in the box body 10. The box body 10 is configured to provide an accommodation space for the battery cell 20, and the box body 10 can have various structures. In some embodiments, the box body 10 can include a first sub-box body 11 and a second sub-box body 12, and the first sub-box body 11 and the second sub-box body 12 are coupled to each other to define an accommodation space for the battery cell 20. The second sub-box body 12 can be a hollow structure with one end open, and the first sub-box body 11 can be a plate structure, and the first sub-box body 11 is coupled to the open end of the second sub-box body 12 to define the accommodation space together with the second sub-box body 12. Alternatively, the first sub-box body 11 and the second sub-box body 12 can both be hollow structures with one end open, and the open end of the first sub-box body 11 is coupled to the open end of the second sub-box body 12.

[0151] In the battery 100, the battery cell 20 can be multiple, and the multiple battery cells 20 can be connected in series, in parallel, or in a mixed connection. The mixed connection means that the multiple battery cells 20 are connected in series and in parallel. The multiple battery cells 20 can be directly connected in series, in parallel, or in a mixed connection, and the whole of the multiple battery cells 20 is accommodated in the box body 10. Alternatively, the battery 100 can be a battery 100 module formed by connecting the multiple battery cells 20 in series, in parallel, or in a mixed connection, and the multiple battery 100 modules are connected in series, in parallel, or in a mixed connection to form a whole, which is accommodated in the box body 10. The battery 100 can further include other structures, for example, the battery 100 can further include a busbar component for electrically connecting the multiple battery cells 20.

[0152] The battery cell 20 can be a secondary battery or a primary battery, and the battery cell 20 can be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto.

[0153] Referring to FIG. 3, FIG. 3 is a structural exploded view of a battery cell according to some embodiments of the present application. As shown in FIG. 3, the battery cell 20 includes a housing 21, an electrode assembly 22, and other functional components. The housing 21 includes a casing 211 having an opening and an end cap 212 closing the opening to isolate the internal environment of the battery cell 20 from the external environment.

[0154] The casing 211 is a component for cooperating with the end cap 212 to form the internal environment of the battery cell 20, in which the internal environment formed can be used to accommodate the electrode assembly 22, electrolyte, and other components. The casing 211 and the end cap 212 can be independent components. The casing 211 can be of various shapes and sizes. Specifically, the shape of the casing 211 can be determined according to the specific shape and size of the electrode assembly 22. The material of the casing 211 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0155] The end cap 212 refers to a component that covers the opening of the casing 211 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 212 can be adapted to the shape of the casing 211 to cooperate with the casing 211. Alternatively, the end cap 212 can be made of a material with certain hardness and strength (such as aluminum alloy), so that the end cap 212 is not easily deformed when subjected to extrusion and collision, so that the battery cell 20 can have higher structural strength, and the reliability can also be improved. The end cap 212 can be provided with functional components such as electrode terminals 23. The electrode terminals 23 can be used to electrically connect with the electrode assembly 22 for outputting or inputting the electrical energy of the battery cell 20. The material of the end cap 212 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which are not specially limited in the embodiments of the present application. In some embodiments, an insulating structure can also be provided on the inner side of the end cap 212, which can be used to isolate the electrical connection components in the casing 211 from the end cap 212 to reduce the risk of short circuit. Exemplarily, the insulating structure can be plastic, rubber, etc.

[0156] The electrode assembly 22 is a component in which electrochemical reactions occur in the battery cell 20. One or more electrode assemblies 22 can be contained in the casing 211. The electrode assembly 22 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and generally has a separator film between the positive electrode sheet and the negative electrode sheet, which is used to separate the positive electrode sheet and the negative electrode sheet to avoid internal short circuit of the positive electrode sheet and the negative electrode sheet. The positive electrode sheet and the negative electrode sheet have a portion of active material constituting the main body of the electrode assembly 22, and a portion of the positive electrode sheet and the negative electrode sheet without active material each constitutes a tab. The positive electrode tab and the negative electrode tab can be located together at one end of the main body or at two ends of the main body, respectively.

[0157] Please refer to FIG. 3, and further refer to FIG. 4 and FIG. 5, FIG. 4 is a sectional view of the first wall and the electrode terminal in an assembled state, and FIG. 5 is an enlarged view of a portion A in FIG. 4.

[0158] The battery cell 20 provided by the embodiments of the present application includes a housing 21, an electrode assembly 22, an electrode terminal 23, and a connecting member 24. The housing 21 includes a first wall 213. The electrode assembly 22 is disposed in the housing 21, and includes a tab 221. The electrode terminal 23 is disposed on the first wall 213, and is electrically connected to the tab 221. The connecting member 24 is at least partially disposed on the outer periphery of the electrode terminal 23, and is used to fix the electrode terminal 23 to the first wall 213. The connecting member 24 is connected to the first wall 213, and includes a first sub-member 241 and a second sub-member 242 connected to each other. The first sub-member 241 is connected to the first wall 213, and the second sub-member 242 has a hardness greater than that of the first sub-member 241.

[0159] The housing 21 can include a shell 211 having an opening and an end cover 212 covering the opening. The first wall 213 can be a wall portion of the shell 211, or can be the end cover 212.

[0160] In some embodiments, the first wall 213 can be the end cover 212.

[0161] In some embodiments, the electrode assembly 22 can have a jelly-roll structure, or can have a stacked structure.

[0162] In some embodiments, the battery cell 20 can be a square battery cell 20, for example, the electrode assembly 22 can have a flat shape. The thickness direction of the electrode assembly 22 can be perpendicular to the thickness direction z of the first wall. When the electrode assembly 22 has a jelly-roll structure, the electrode assembly 22 includes a flat region and a bent region. The thickness direction of the electrode assembly 22 is parallel to the stacking direction of the electrode tab in the flat region. When the electrode assembly 22 has a stacked structure, the thickness direction of the electrode assembly 22 is parallel to the stacking direction of the electrode tab.

[0163] The first wall 213 can be provided with an electrode lead-out hole 2131, and the electrode terminal 23 can cover the electrode lead-out hole 2131, so as to facilitate the electrical connection between the electrode terminal 23 and the tab 221 through the electrode lead-out hole 2131. For example, a portion of the electrode terminal 23 can extend into the electrode lead-out hole 2131, so as to electrically connect the electrode terminal 23 to the tab 221.

[0164] One end of the first sub-component 241 can be connected with the first wall 213, and the other end of the first sub-component 241 clamps the electrode terminal 23 in cooperation with the first wall 213 to fix the electrode terminal 23 to the first wall 213. The connection manner of the first sub-component 241 with the first wall 213 can be various, for example, one end of the first sub-component 241 is welded with the first wall 213, or one end of the first sub-component 241 is integrally formed with the first wall 213. The fixing manner of the first sub-component 241 to the electrode terminal 23 can be various, for example, the other end of the first sub-component 241 directly abuts against the electrode terminal 23, or the other end of the first sub-component 241 abuts against the electrode terminal 23 through the second sub-component 242.

[0165] The "the connecting piece 24 is at least partially arranged at the outer periphery of the electrode terminal 23" means that the connecting piece 24 is arranged along the circumference of the electrode terminal 23, and the connecting piece 24 can be arranged on a part or a circle of the circumference arranged around the central axis Q of the electrode terminal 23, so that the connecting piece 24 can limit the electrode terminal 23 in the circumferential direction of the electrode terminal 23.

[0166] The first sub-component 241 and the second sub-component 242 are two components constituting the connecting piece 24, and the first sub-component 241 and the second sub-component 242 are connected with each other, for example, the first sub-component 241 and the second sub-component 242 are press-fitted to be integrated, or the first sub-component 241 and the second sub-component 242 are connected by adhesion, or the first sub-component 241 and the second sub-component 242 are connected by welding, or the first sub-component 241 and the second sub-component 242 are connected by riveting.

[0167] The material of the second sub-component 242 is different from that of the first sub-component 241, and the hardness of the second sub-component 242 is greater than that of the first sub-component 241, so that the connecting piece 24 has high overall strength after the second sub-component 242 is connected and cooperated with the first sub-component 241.

[0168] In some embodiments, the materials of the first sub-component 241 and the second sub-component 242 can both be metal materials, so that the first sub-component 241 and the second sub-component 242 have certain strength.

[0169] In some embodiments, the material of the first sub-component 241 can be a metal material, and the material of the second sub-component 242 can be a non-metal material with high hardness.

[0170] The hardness of the first sub-component 241 and the hardness of the second sub-component 242 mentioned in the embodiments of the present application can be Vickers hardness. The measurement method of Vickers hardness is as follows: a diamond square cone indenter with a load of less than 120 kg and a vertex angle of 136° is pressed into the surface of the material, and the Vickers hardness value (Hv) is obtained by dividing the surface area of the material indentation pit by the load value. The standard test holding time is 10S-15S.

[0171] In some embodiments, the hardness of the first sub-component 241 can be greater than or equal to the hardness of the first wall 213.

[0172] According to the battery cell 20 of the embodiments of the present application, the first sub-component 241 and the second sub-component 242 are connected to each other, the hardness of the second sub-component 242 is greater than the hardness of the first sub-component 241, which can improve the overall strength of the connecting piece 24, improve the anti-deformation ability of the connecting piece 24, so as to improve the restraining effect of the connecting piece 24 on the electrode terminal 23, reduce the risk of movement of the electrode terminal 23 relative to the first wall 213, improve the connection reliability of the electrode terminal 23 with other components (such as a adapter or a tab 221), and improve the reliability of the battery cell 20.

[0173] In some embodiments, the electrode terminal 23 can include a first body part 231 and a second body part 232. Along the thickness direction z of the first wall, the second body part 232 is located on the side of the first wall 213 away from the inside of the battery cell 20, and the first body part 231 is located on the side of the second body part 232 away from the inside of the battery cell 20. The first body part 231 and the second body part 232 can both be cylindrical, the second body part 232 is coaxially arranged with the first body part 231, the diameter of the first body part 231 is smaller than the diameter of the second body part 232, and along the radial direction J of the electrode terminal, the second body part 232 protrudes from the outer peripheral surface of the first body part 231. The second body part 232 is configured to cover the electrode lead-out hole 2131, and the first body part 231 is used for electrical connection with the conductive component (such as a tab, a busbar member, etc.) outside the battery cell 20.

[0174] In some embodiments, the first sub-component 241 and the second sub-component 242 are stacked along the thickness direction z of the first wall. Along the thickness direction z of the first wall, the first sub-component 241 can be located on the side of the second sub-component 242 facing the electrode assembly 22, or the first sub-component 241 can also be located on the side of the second sub-component 242 away from the electrode assembly 22.

[0175] In some embodiments, the first sub-component 241 can be a flat plate structure parallel to the first wall 213, and the second sub-component 242 can also be a flat plate structure parallel to the first wall 213; or, the first sub-component 241 can be a bent structure, and the second sub-component 242 can also be a bent structure; or, the first sub-component 241 can be a bent structure, and the second sub-component 242 can be a flat plate structure.

[0176] In some embodiments, the number of electrode terminals 23 is two, and the two electrode terminals 23 are a positive electrode terminal and a negative electrode terminal, respectively; and the number of connectors 24 is two, one connector 24 is used to fix the positive electrode terminal to the first wall 213, and the other connector 24 is used to fix the negative electrode terminal to the first wall 213. Optionally, the structure of the positive electrode terminal and the negative electrode terminal can be the same, and for the convenience of description, the electrode terminal 23 mentioned in the embodiments of the present application can be a positive electrode terminal or a negative electrode terminal.

[0177] According to some embodiments of the present application, the melting point of the first sub-component 241 is greater than or equal to 500℃ and less than or equal to 1000℃, the melting point of the second sub-component 242 is greater than or equal to 1050℃ and less than or equal to 3500℃, and the melting point of the first wall 213 is greater than or equal to 500℃ and less than or equal to 1000℃.

[0178] The melting point of the first sub-component 241 can be any one of 500℃, 550℃, 600℃, 650℃, 700℃, 750℃, 800℃, 850℃, 900℃, 950℃, 1000℃, or a range between any two of them.

[0179] The melting point of the second sub-component 242 can be any one of 1050℃, 1150℃, 1250℃, 1350℃, 1450℃, 1550℃, 1650℃, 1750℃, 1850℃, 1950℃, 2050℃, 2150℃, 2250℃, 2350℃, 2450℃, 2550℃, 2650℃, 2750℃, 2850℃, 2950℃, 3050℃, 3150℃, 3250℃, 3350℃, 3450℃, 3500℃, or a range between any two of them.

[0180] The melting point of the first wall 213 can be any one of 500℃, 550℃, 600℃, 650℃, 700℃, 750℃, 800℃, 850℃, 900℃, 950℃, 1000℃, or a range between any two of them.

[0181] In some embodiments, the melting point of the first sub-component 241 may be the same as the melting point of the first wall 213, or the melting point of the first sub-component 241 may be close to the melting point of the first wall 213, so as to facilitate welding of the first sub-component 241 to the first wall 213 and make the connection between the first sub-component 241 and the first wall 213 stable.

[0182] Compared to the melting point of the first sub-component 241 and the melting point of the first wall 213, the melting point of the second sub-component 242 is higher, which has a better high-temperature resistance and is not easily deformed by heat.

[0183] According to some embodiments of this application, the first sub-component 241 is welded to the second sub-component 242 to ensure a secure connection between them. For example, the first sub-component 241 and the second sub-component 242 are connected by friction welding.

[0184] According to some embodiments of this application, the hardness of the first sub-component 241 can be 30 kgf / mm². 2 ~170kgf / mm 2 The hardness of the second sub-component 242 can be 100 kgf / mm². 2 ~500kgf / mm 2 .

[0185] Optionally, the hardness of the first sub-component 241 can be 30 kgf / mm². 2 40kgf / mm 2 50kgf / mm 2 60kgf / mm 2 70kgf / mm 2 80kgf / mm 2 90kgf / mm 2 100kgf / mm 2 110kgf / mm 2 120kgf / mm 2 130kgf / mm 2 140kgf / mm 2 150kgf / mm 2 160kgf / mm 2 170kgf / mm 2 The range between any one of them or any two of them.

[0186] Optionally, the hardness of the second sub-component 242 can be 100 kgf / mm². 2 120kgf / mm 2 140kgf / mm 2 160kgf / mm 2 180kgf / mm2 , 200 kgf / mm 2 , 220 kgf / mm 2 , 240 kgf / mm 2 , 260 kgf / mm 2 , 280 kgf / mm 2 , 300 kgf / mm 2 , 320 kgf / mm 2 , 340 kgf / mm 2 , 360 kgf / mm 2 , 380 kgf / mm 2 , 400 kgf / mm 2 , 420 kgf / mm 2 , 440 kgf / mm 2 , 460 kgf / mm 2 , 480 kgf / mm 2 , 500 kgf / mm 2 Any one of the above ranges or any range between any two of the above ranges.

[0187] In the above scheme, the hardness of the first sub-component 241 meets the above range, the first sub-component 241 has good deformation resistance, the hardness of the second sub-component 242 meets the above range, the second sub-component 242 has better deformation resistance than the first sub-component 241, and the overall deformation resistance of the structure formed by the cooperation of the second sub-component 242 and the first sub-component 241 is better, so as to constrain the movement of the electrode terminal 23 relative to the first wall 213.

[0188] According to some embodiments of the present application, the material of the first sub-component 241 is the same as that of the first wall 213.

[0189] The material of the first sub-component 241 is the same as that of the first wall 213, the hardness of the first sub-component 241 is the same as that of the first wall 213, and the hardness of the second sub-component 242 is greater than that of the first wall 213.

[0190] In the above scheme, the material of the first sub-component 241 is the same as that of the first wall 213, which facilitates the welding of the first sub-component 241 and the first wall 213.

[0191] According to some embodiments of the present application, the base metal of the first sub-component 241 is the same as that of the second sub-component 242.

[0192] The materials of the first sub-component 241 and the second sub-component 242 are both alloys. The base metal refers to the main component metal of the alloy.

[0193] In some embodiments, the material of the first sub-component 241 can be the same as the material of the second sub-component 242, for example, the components of the first sub-component 241 are the same as the components of the second sub-component 242; or the material of the first sub-component 241 can be different from the material of the second sub-component 242, for example, the components of the first sub-component 241 are different from the components of the second sub-component 242.

[0194] In the above solution, the material of the first sub-component 241 and the material of the second sub-component 242 are both alloys, and the base metal of the first sub-component 241 is the same as the base metal of the second sub-component 242, which facilitates processing and manufacturing.

[0195] According to some embodiments of the present application, the first sub-component 241 is laser welded with the first wall 213.

[0196] The first sub-component 241 and the first wall 213 are both metals, and the material of the first sub-component 241 can be the same as the material of the first wall 213 or can be different.

[0197] In the above solution, the first sub-component 241 is laser welded with the first wall 213, the welding quality is high, and the first sub-component 241 has small deformation after welding.

[0198] According to some embodiments of the present application, the material of the first sub-component 241 includes aluminum or an aluminum alloy, and the material of the second sub-component 242 includes steel, stainless steel, copper, a copper alloy, titanium, or a titanium alloy.

[0199] Aluminum or an aluminum alloy has high hardness, so that the first sub-component 241 has high hardness, which facilitates connection with the first wall 213 while meeting the strength requirement.

[0200] Steel, stainless steel, copper, a copper alloy, titanium, or a titanium alloy has high hardness, and the second sub-component 242 has high overall strength after being combined with the first sub-component 241.

[0201] According to some embodiments of the present application, the material of the first sub-component 241 includes steel or stainless steel, and the material of the second sub-component 242 includes titanium or a titanium alloy.

[0202] When the material of the first sub-component 241 includes steel or stainless steel, the first sub-component 241 has high hardness and has good anti-deformation ability.

[0203] When the material of the second sub-component 242 includes titanium or a titanium alloy, the second sub-component 242 has high hardness, and the second sub-component 242 has high overall strength after being combined with the first sub-component 241.

[0204] In the above scheme, the material of the first sub-component 241 and the material of the second sub-component 242 satisfy the above condition, the first sub-component 241 and the second sub-component 242 both have high hardness, and the connecting piece 24 has high overall strength.

[0205] In the above embodiment, it is introduced that the material of the second sub-component 242 can be metal, so that the second sub-component 242 has high strength. In some other embodiments, the material of the second sub-component 242 can also be non-metal with certain hardness, and the following will introduce the embodiment in which the material of the second sub-component 242 is non-metal.

[0206] According to some embodiments of the present application, the material of the second sub-component 242 includes ceramic, high polymer plastic or carbon fiber reinforced composite material.

[0207] The ceramic has high hardness, and when the material of the second sub-component 242 is ceramic, the second sub-component 242 can be bonded with the first sub-component 241.

[0208] The high polymer plastic can include polyethylene, polypropylene or polycarbonate, etc. In addition, reinforcing materials (such as glass fiber, carbon fiber or mineral) can be added in the high polymer plastic, which can further improve the strength and hardness of the high polymer plastic. When the material of the second sub-component 242 is high polymer plastic, the second sub-component 242 can be injection molded to be connected to the first sub-component 241.

[0209] The carbon fiber reinforced composite material is a widely used high-strength and high-hardness plastic material, which can be composed of carbon fiber and resin matrix. The carbon fiber reinforced composite material has the characteristics of light weight, high strength and high hardness. When the material of the second sub-component 242 is carbon fiber reinforced composite material, the second sub-component 242 can be hot melt connected to the first sub-component 241.

[0210] In the above scheme, the ceramic, the high polymer plastic or the carbon fiber reinforced composite material has high hardness.

[0211] Please refer to FIG. 6, which is a schematic diagram of the welding state of the first sub-component and the first wall according to some embodiments of the present application. According to some embodiments of the present application, the first sub-component 241 is welded with the first wall 213 to form a first welding mark 246, the first sub-component 241 has a first surface 2411 facing away from the electrode assembly 22, and the first welding mark 246 extends from the first surface 2411 to the first wall 213 along the thickness direction z of the first wall.

[0212] The first sub-component 241 also has a second surface 2412 facing the electrode assembly 22, the first surface 2411 and the second surface 2412 are oppositely arranged in the thickness direction z of the first wall, the first weld 246 extends from the first surface 2411 towards the electrode assembly 22 in the thickness direction z of the first wall, and the first weld 246 extends to the first wall 213 after passing the second surface 2412.

[0213] For example, along the thickness direction z of the first wall, the second surface 2412 of the first sub-component 241 is in direct contact with the first wall 213, and after the first sub-component 241 is welded with the first wall 213, the first weld 246 extends to the first wall 213 after passing the second surface 2412. For another example, along the thickness direction z of the first wall, the second sub-component 242 is located between the first sub-component 241 and the first wall 213, and after the first sub-component 241 is welded with the first wall 213, the first weld 246 extends to the first wall 213 after passing the first sub-component 241 and the second sub-component 242.

[0214] In the above scheme, the first weld 246 extends to the first wall 213, and the first weld 246 has a large size so that the first sub-component 241 is firmly connected with the first wall 213.

[0215] According to some embodiments of the present application, the second sub-component 242 has a projection on the same projection plane perpendicular to the thickness direction z of the first wall, and the projection of the second sub-component 242 at least partially overlaps with the projection of the electrode terminal 23.

[0216] As viewed along the thickness direction z of the first wall, the second sub-component 242 can partially overlap with the electrode terminal 23, or the second sub-component 242 can fully overlap with the electrode terminal 23, so that the second sub-component 242 has a large overlapping area with the electrode terminal 23.

[0217] In the above scheme, the projection of the second sub-component 242 has a large overlapping area with the projection of the electrode terminal 23, and since the second sub-component 242 has high hardness, the connecting member 24 has high deformation resistance in the region provided with the second sub-component 242, and the connecting member 24 has a good constraint effect on the electrode terminal 23 in the thickness direction z of the first wall, which facilitates limiting the movement of the electrode terminal 23 in the thickness direction z of the first wall.

[0218] Please refer to FIG. 5, and further refer to FIG. 7, which is a partial enlarged view of B in FIG. 5. According to some embodiments of the present application, along the thickness direction z of the first wall, the connecting member 24 has an overlapping region 243 overlapping with the electrode terminal 23, and at least part of the second sub-component 242 is arranged in the overlapping region 243.

[0219] As viewed along the thickness direction z of the first wall, a part of the connecting member 24 overlaps with the electrode terminal 23, and this part is the overlapping region 243.

[0220] The first sub-component 241 can be the base of the connecting member 24, and a portion of the first sub-component 241 is arranged in the overlapping region 243, and at least a portion of the second sub-component 242 is arranged in the overlapping region 243, so that both the first sub-component 241 and the second sub-component 242 are arranged in the overlapping region 243. For example, a portion of the first sub-component 241 is arranged in the overlapping region 243, and a portion of the second sub-component 242 can be arranged in the overlapping region 243, and another portion of the second sub-component 242 is arranged outside the overlapping region 243, so that the second sub-component 242 has a larger connection area with the first sub-component 241, and the connecting member 24 has a higher overall strength; or, a portion of the first sub-component 241 is arranged in the overlapping region 243, and the entire second sub-component 242 is arranged in the overlapping region 243, so that the connecting member 24 has a higher strength in the overlapping region 243, so as to limit the movement of the electrode terminal 23 by the overlapping region 243.

[0221] In the above scheme, at least a portion of the second sub-component 242 is arranged in the overlapping region 243, so that the connecting member 24 has a higher hardness and strength in the overlapping region 243, and the overlapping region 243 is not easy to deform, so as to improve the restraining effect of the connecting member 24 on the electrode terminal 23, and reduce the risk of movement of the electrode terminal 23 relative to the first wall 213 in the thickness direction z of the first wall.

[0222] Please refer to FIG. 5, according to some embodiments of the present application, the first sub-component 241 includes a first segment 241a and a second segment 241b, the first segment 241a is connected to the first wall 213, and the second segment 241b is located on the inner circumferential side of the first segment 241a, and is farther away from the electrode assembly 22 (please refer to FIG. 3) than the first segment 241a in the thickness direction z of the first wall; and the second segment 241b at least partially overlaps with the second sub-component 242 in the thickness direction z of the first wall.

[0223] The first segment 241a can be connected to the first wall 213 in various ways, for example, the first segment 241a can be directly connected to the first wall 213, or the first segment 241a can be connected to the first wall 213 through other structures (other parts of the first sub-component 241 or other connecting components).

[0224] The inner circumferential side of the first segment 241a refers to the side of the first segment 241a facing the central axis Q of the electrode terminal, and the peripheral surface surrounding the central axis Q of the electrode terminal.

[0225] The second segment 241b is farther away from the electrode assembly 22 than the first wall 213 in the thickness direction z of the first wall, and the first sub-component 241 can be a bent structure, so as to clamp the electrode terminal 23 in cooperation with the first wall 213.

[0226] In some embodiments, the second section 241b at least partially overlaps with the electrode terminal 23 along the thickness direction z of the first wall. For example, the second section 241b partially overlaps with the second body part 232 along the thickness direction z of the first wall.

[0227] In some embodiments, the second section 241b partially overlaps with the second sub-component 242, or the second section 241b fully overlaps with the second sub-component 242. The connector 24 has a higher strength at the overlapping position of the second section 241b and the second sub-component 242, and has a higher deformation resistance, so that the connector 24 has a better constraint effect on the electrode terminal 23.

[0228] In the above scheme, the first sub-component 241 is a bent structure, and the second section 241b is farther away from the electrode assembly 22 than the first wall 213, so as to reasonably utilize the space along the thickness direction z of the first wall, and facilitate the cooperation between the second section 241b and the electrode terminal 23. The second section 241b at least partially overlaps with the second sub-component 242 along the thickness direction z of the first wall, so that the hardness of the connector 24 at the corresponding position of the second section 241b is higher, the connector 24 has a higher deformation resistance, and the connector 24 has a higher constraint effect on the electrode terminal 23.

[0229] Please refer to FIG. 5. According to some embodiments of the present application, the first section 241a at least partially overlaps with the second sub-component 242 along the thickness direction z of the first wall.

[0230] In some embodiments, the second sub-component 242 has an overlapping part with the first section 241a and the second section 241b along the thickness direction z of the first wall. The second sub-component 242 can be a continuous structure, for example, the second sub-component 242 can extend from the first section 241a to the second section 241b. The second sub-component 242 can also be an intermittent structure, for example, a part of the second sub-component 242 overlaps with the first section 241a, and another part of the second sub-component 242 overlaps with the second section 241b.

[0231] In the above scheme, the first section 241a also at least partially overlaps with the second sub-component 242, and the second sub-component 242 has a larger overlapping area with the first sub-component 241, which can further improve the overall strength of the connector 24, improve the deformation resistance of the connector 24, and improve the constraint effect of the connector 24 on the electrode terminal 23.

[0232] According to some embodiments of the present application, the first sub-component 241 further comprises a third section 241c, the first section 241a is connected to the first wall 213 through the third section 241c, the first section 241a is located at the inner circumferential side of the third section 241c, the second section 241b is farther away from the electrode assembly 22 than the third section 241c along the thickness direction z of the first wall, and the first section 241a connects the second section 241b and the third section 241c.

[0233] In some embodiments, the first sub-component 241 can be annular, and the third section 241c, the first section 241a and the second section 241b can be continuously distributed along the radial direction J of the electrode terminal, for example, the first sub-component 241 is arranged around the central axis Q of the electrode terminal, and the third section 241c is farther away from the central axis Q of the electrode terminal than the second section 241b.

[0234] In some embodiments, the first section 241a, the second section 241b and the third section 241c can be integrally formed, for example, the first sub-component 241 is formed by stamping.

[0235] The first sub-component 241 is located at the side of the first wall 213 away from the electrode assembly 22, and the first sub-component 241 can be a bent structure, the first section 241a is bent towards the direction away from the inside of the battery monomer 20 relative to the third section 241c, the second section 241b is bent towards the central axis Q of the electrode terminal relative to the first section 241a, and the second section 241b is farther away from the electrode assembly 22 than the third section 241c along the thickness direction z of the first wall.

[0236] In the above scheme, the first section 241a is connected to the first wall 213 through the third section 241c, which facilitates the bending of the first sub-component 241, facilitates the cooperation of the first sub-component 241 with the first wall 213 and the electrode terminal 23, and facilitates processing and manufacturing.

[0237] Please refer to FIG. 5, according to some embodiments of the present application, the third section 241c and the second sub-component 242 at least partially overlap along the thickness direction z of the first wall.

[0238] In some embodiments, the second section 241b and the third section 241c respectively overlap with the second sub-component 242 along the thickness direction z of the first wall, which can improve the strength of the connecting piece 24 at the connection between the second section 241b and the second sub-component 242 and at the connection between the third section 241c and the second sub-component 242, improve the overall strength of the connecting piece 24, and reduce the risk of deformation of the connecting piece 24 under stress.

[0239] In the above scheme, the third section 241c at least partially overlaps with the second sub-component 242, so that the second sub-component 242 has a larger overlapping area with the first sub-component 241, and the connector 24 has higher overall strength, which improves the constraint effect of the connector 24 on the electrode terminal 23 and improves the connection firmness of the connector 24 and the first wall 213.

[0240] Please refer to FIG. 5. According to some embodiments of the present application, the second sub-component 242 includes a first reinforcing section 242d which is arranged in a stack with the first section 241a, and a second reinforcing section 242e which is arranged in a stack with the second section 241b, and the first reinforcing section 242d is connected with the second reinforcing section 242e.

[0241] The first reinforcing section 242d is arranged in a stack with the first section 241a, so as to improve the strength of the connector 24 at the first section 241a.

[0242] The second reinforcing section 242e is arranged in a stack with the second section 241b, so as to improve the strength of the connector 24 at the second section 241b.

[0243] The first reinforcing section 242d is connected with the second reinforcing section 242e, and the first reinforcing section 242d and the second reinforcing section 242e can be integrally formed; or the first reinforcing section 242d and the second reinforcing section 242e can be connected by welding.

[0244] In the above scheme, the first reinforcing section 242d is connected with the second reinforcing section 242e, which can constrain the deformation of the connection between the first section 241a and the second section 241b, and reduce the risk of the second section 241b being raised relative to the first section 241a.

[0245] According to some embodiments of the present application, the second sub-component 242 further includes a third reinforcing section 242f which is arranged in a stack with the third section 241c, and the third reinforcing section 242f is connected with the first reinforcing section 242d.

[0246] The third reinforcing section 242f, the first reinforcing section 242d, and the second reinforcing section 242e can be integrally formed, which facilitates processing and manufacturing; or the third reinforcing section 242f can be connected with the first reinforcing section 242d by welding.

[0247] The third reinforcing section 242f is arranged in a stack with the third section 241c, so as to improve the strength of the connector 24 at the third section 241c.

[0248] In the above scheme, the third reinforcing section 242f is connected with the first reinforcing section 242d, which can constrain the deformation of the connection between the first section 241a and the third section 241c, and reduce the risk of the first section 241a being raised relative to the third section 241c.

[0249] According to some embodiments of the present application, the first sub-component 241 and the second sub-component 242 are continuous structures, and the first segment 241a, the second segment 241b and the third segment 241c all overlap with the second sub-component 242 along the thickness direction z of the first wall, so that the second sub-component 242 has a large connecting area with the first sub-component 241, and the overall strength of the connecting piece 24 can be improved.

[0250] According to some embodiments of the present application, the second sub-component 242 surrounds the electrode terminal 23.

[0251] The second sub-component 242 can be annular, and the second sub-component 242 is arranged around the central axis Q of the electrode terminal 23, and the second sub-component 242 is sleeved outside the first body part 231 of the electrode terminal 23.

[0252] In the above scheme, the second sub-component 242 can be annular, so that the second sub-component 242 surrounds the electrode terminal 23, and the second sub-component 242 has a high constraint effect on the electrode terminal 23 in the circumferential direction thereof.

[0253] Please refer to FIG. 5, according to some embodiments of the present application, the orthographic projection of the first sub-component 241 and the orthographic projection of the second sub-component 242 at least partially overlap on the same projection plane perpendicular to the thickness direction z of the first wall.

[0254] The orthographic projection of the first sub-component 241 and the orthographic projection of the second sub-component 242 at least partially overlap on the same projection plane perpendicular to the thickness direction z of the first wall.

[0255] In the above scheme, the orthographic projection of the first sub-component 241 and the orthographic projection of the second sub-component 242 at least partially overlap, the first sub-component 241 and the second sub-component 242 have a large connecting area, and the second sub-component 242 can strengthen the first sub-component 241 in the thickness direction z of the first wall, improve the anti-deformation ability of the first sub-component 241, so that the connecting piece 24 has high overall strength, and the movement of the electrode terminal 23 in the thickness direction z of the first wall can be limited.

[0256] Please refer to FIG. 5, according to some embodiments of the present application, the orthographic projection of the first sub-component 241 and the orthographic projection of the second sub-component 242 completely overlap on the same projection plane perpendicular to the thickness direction z of the first wall.

[0257] Projecting along the thickness direction z of the first wall, on the same projection plane perpendicular to the thickness direction z of the first wall, the orthographic projection of the first sub-component 241 and the orthographic projection of the second sub-component 242 completely overlap, maximizing the connection area between the first sub-component 241 and the second sub-component 242, thereby improving the overall strength after the first sub-component 241 and the second sub-component 242 are joined together, and making the connector 24 have high overall strength.

[0258] In the above scheme, the orthographic projection of the first sub-component 241 completely overlaps with the orthographic projection of the second sub-component 242, further enhancing the overall strength of the connector 24.

[0259] Referring to Figures 3 and 5, according to some embodiments of this application, the connector 24 is located on the side of the first wall 213 opposite to the electrode assembly 22.

[0260] In the above scheme, the connector 24 is located on the outside of the first wall 213, which makes it convenient for the connector 24 to fix the electrode terminal 23 to the first wall 213 after the electrode terminal 23 is assembled with the first wall 213. At the same time, it reduces the risk of interference between the connector 24 and the electrode assembly 22.

[0261] Referring to Figures 3 and 5, according to some embodiments of this application, along the thickness direction z of the first wall, the second sub-component 242 is located on the side of the first sub-component 241 facing the electrode assembly 22.

[0262] In some embodiments, when the connector 24 is located on the side of the first wall 213 away from the electrode assembly 22, the second sub-component 242 is located on the side of the first sub-component 241 facing the electrode assembly 22. The first sub-component 241 can abut against the electrode assembly 22 through the second sub-component 242. When the electrode terminal 23 moves relative to the first wall 213 in the thickness direction z of the first wall, the second sub-component 242 can bear the force of the electrode terminal 23 relative to the first sub-component 241 first. Since the second sub-component 242 has high hardness, the second sub-component 242 has a better constraint effect on the electrode terminal 23.

[0263] In particular, when the projection of the first sub-component 241 and the projection of the second sub-component 242 completely overlap along the thickness direction z of the first wall, there is a large connection area between the second sub-component 242 and the first sub-component 241. The second sub-component 242 can constrain the electrode terminal 23, and at the same time, reduce the risk of damage to the connection position between the first sub-component 241 and the first wall 213 caused by the force of the electrode terminal 23, thereby reducing the risk of the electrode terminal 23 moving.

[0264] Please refer to FIG. 8, which is a schematic diagram of the cooperation between the second sub-component and the first sub-component according to some embodiments of the present application. FIG. 8 is a partial schematic diagram of the battery cell, and FIG. 8 shows the cooperation between the second sub-component and the first sub-component. According to some embodiments of the present application, along the thickness direction z of the first wall, the second sub-component 242 is located on the side of the first sub-component 241 away from the electrode assembly 22; the first sub-component 241 and the first wall 213 are connected to form a fixed portion 244, and the second sub-component 242 does not overlap the fixed portion 244.

[0265] As viewed along the thickness direction z of the first wall, the second sub-component 242 does not cover the connection between the first sub-component 241 and the first wall 213.

[0266] For example, the first sub-component 241 and the first wall 213 are welded to form a first weld, and the first weld can be the fixed portion 244. The second sub-component 242 does not cover the fixed portion 244, so as to facilitate the welding of the first sub-component 241 and the first wall 213. For another example, the first sub-component 241 and the first wall 213 are integrally formed, and the connection between the first sub-component 241 and the first wall 213 is the fixed portion 244. In the embodiment in which the first sub-component 241 is a bent structure, the root of the bend of the first sub-component 241 is the fixed portion 244. The second sub-component 242 does not cover the fixed portion 244, so as to facilitate the fixation of the electrode terminal 23 to the first wall 213 after the bending of the first sub-component 241.

[0267] In the above scheme, the second sub-component 242 is located on the side of the first sub-component 241 away from the electrode assembly 22, the second sub-component 242 does not overlap the fixed portion 244, and the second sub-component 242 does not block the connection position of the first sub-component 241 and the first wall 213, which can facilitate the connection of the first sub-component 241 and the first wall 213.

[0268] According to some embodiments of the present application, the connecting piece 24 can be located on the side of the first wall 213 facing the electrode assembly 22.

[0269] For example, the connecting piece 24 can be a bent structure, the first sub-component 241 includes a first segment 241a, a second segment 241b, and a third segment 241c, the first segment 241a is connected to the first wall 213, the third segment 241c is located on the inner circumferential side of the first segment 241a, and along the thickness direction z of the first wall, the third segment 241c is closer to the electrode assembly 22 than the first segment 241a, and the second segment 241b connects the first segment 241a and the third segment 241c. Along the thickness direction z of the first wall, the third segment 241c at least partially overlaps the second body portion 232, so as to facilitate the fixation of the electrode terminal 23 to the first wall 213 by the connecting piece 24.

[0270] Please refer to FIG. 4 and FIG. 5, according to some embodiments of the present application, the first sub-component 241 and the second sub-component 242 are both arranged around the electrode terminal 23.

[0271] The first sub-component 241 and the second sub-component 242 can both be annular structures, and when the first sub-component 241 and the second sub-component 242 are both arranged around the electrode terminal 23, the center line of the first sub-component 241 and the center line of the second sub-component 242 can coincide. Alternatively, the center line of the first sub-component 241 can also coincide with the center line of the electrode terminal 23.

[0272] In the above scheme, the first sub-component 241 and the second sub-component 242 are both annular, and can exert a constraint force on the electrode terminal 23 at any position in the circumferential direction of the electrode terminal 23, thereby having a good constraint effect on the electrode terminal 23.

[0273] Please refer to FIG. 5, according to some embodiments of the present application, the battery monomer 20 further comprises a first insulating member 25, the first insulating member 25 is at least partially arranged between the electrode terminal 23 and the connecting member 24; the connecting member 24 has a through hole 245, a part of the first insulating member 25 and a part of the electrode terminal 23 are accommodated in the through hole 245, and along the radial direction J of the electrode terminal, the first insulating member 25 is located between the electrode terminal 23 and the connecting member 24.

[0274] The first insulating member 25 is an electrically insulating component, and the material of the first insulating member 25 can be plastic, rubber, etc., so as to insulate and isolate the electrode terminal 23 and the connecting member 24.

[0275] The first insulating member 25 is at least partially arranged between the electrode terminal 23 and the connecting member 24, and the first insulating member 25 is connected to the electrode terminal 23 and the connecting member 24, so as to separate the electrode terminal 23 and the connecting member 24.

[0276] In some embodiments, the first insulating member 25 can be annular, and the first insulating member 25 is arranged around the electrode terminal 23, so as to insulate and isolate the electrode terminal 23 and the connecting member 24 at any position in the circumferential direction of the electrode terminal 23.

[0277] The connecting member 24 is annular, and the inner circumferential surface of the connecting member 24 forms the through hole 245; the connecting member 24 is arranged around the first body part 231 of the electrode terminal 23, so that a part of the electrode terminal 23 is accommodated in the through hole 245; at the same time, the first insulating member 25 is also arranged around the first body part 231 of the electrode terminal 23, a part of the first insulating member 25 is accommodated in the through hole 245, and along the radial direction J of the electrode terminal, the first insulating member is located between the electrode terminal 23 and the connecting member 24, so as to achieve the isolation of the electrode terminal 23 and the connecting member 24.

[0278] In some embodiments, the through hole 245 can be a circular hole for facilitating manufacturing. Optionally, the central axis of the through hole 245 can coincide with the central axis Q of the electrode terminal.

[0279] In some embodiments, the first insulating member 25 can be injection molded between the electrode terminal 23 and the connecting member 24 for facilitating manufacturing.

[0280] In the above scheme, the first insulating member 25 is at least partially disposed between the electrode terminal 23 and the connecting member 24, and insulates and separates the electrode terminal 23 and the connecting member 24, thereby reducing the risk of positive and negative short circuit.

[0281] Please refer to FIG. 5. According to some embodiments of the present application, the first sub-component 241 and the second sub-component 242 are stacked, and the thickness of at least part of the second sub-component 242 is smaller than the thickness of the first sub-component 241 along the stacking direction.

[0282] For the purpose of description, in FIG. 5, the dimension indicated by H1 is the thickness of the first sub-component 241, and the dimension indicated by H2 is the thickness of the second sub-component 242.

[0283] The first sub-component 241 and the second sub-component 242 can be stacked along the thickness direction z of the first wall, for example, the first sub-component 241 and the second sub-component 242 can both be plate-shaped, and after being stacked along the thickness direction z of the first wall, the first sub-component 241 and the second sub-component 242 are simultaneously subjected to stamping and bending, and the first sub-component 241 and the second sub-component 242 are stacked after being bent.

[0284] “Along the stacking direction, the thickness of at least the second sub-component 242 is smaller than the thickness of the first sub-component 241” means that at any position along the stacking direction of the first sub-component 241 and the second sub-component 242, the thickness of the second sub-component 242 can be smaller than the thickness of the first sub-component 241; or within most of the extension direction of the first sub-component 241, the thickness of the second sub-component 242 can be smaller than the thickness of the first sub-component 241.

[0285] It should be noted that the thickness of the first sub-component 241 herein refers to the dimension of the first sub-component 241 along the stacking direction, i.e., the dimension of the cross section of the first sub-component 241 along the stacking direction. For example, when part of the first sub-component 241 and part of the second sub-component 242 are stacked in the up-down direction, the thickness of the part of the first sub-component 241 refers to the dimension in the up-down direction. Similarly, the thickness of the second sub-component 242 is obtained in the same way as the thickness of the first sub-component 241.

[0286] In the above scheme, in the stacking direction, the thickness of the second sub-component 242 is less than the thickness of the first sub-component 241, the overall thickness of the connecting piece 24 is reduced in the case of improving the overall strength of the connecting piece 24, and the space occupation is reduced.

[0287] According to some embodiments of the present application, the thickness of the first sub-component 241 is H1, the thickness of the second sub-component 242 is H2, and 0.5≤H1 / (H1+H2)≤0.9 is satisfied.

[0288] H1 / (H1+H2) can be: in the stacking direction, the proportion of the thickness of the first sub-component 241 to the overall thickness of the connecting piece 24.

[0289] Optionally, H1 / (H1+H2) can be any one of 0.5, 0.6, 0.7, 0.8, 0.9 or a range between any two of them.

[0290] In the above scheme, the thickness of the first sub-component 241 and the thickness of the second sub-component 242 satisfy the above relationship, on the one hand, the thickness of the first sub-component 241 is thick, so as to improve the welding reliability of the first sub-component 241 and the first wall 213; on the other hand, the second sub-component 242 has a certain thickness, the second sub-component 242 has high hardness, and the second sub-component 242 has high deformation resistance after being stacked with the first sub-component 241, and the connecting piece 24 can have high overall strength.

[0291] Please refer to FIG. 9 and FIG. 10, FIG. 9 is a sectional view of the first sub-component and the second sub-component in the assembled state according to some embodiments of the present application, and FIG. 10 is a partial enlarged view of C in FIG. 9. According to some embodiments of the present application, the first sub-component 241 includes a first main body part 241d and a first connecting part 241e, the first connecting part 241e is annular, the first main body part 241d is connected to the inner circumferential side of the first connecting part 241e, the first connecting part 241e is connected with the first wall 213, the first main body part 241d at least partially overlaps with the second sub-component 242 along the thickness direction z of the first wall, and the thickness of the first connecting part 241e is greater than the thickness of the first main body part 241d.

[0292] The first connecting part 241e is arranged around the central axis Q of the electrode terminal.

[0293] The inner circumferential side of the first connecting part 241e refers to the side of the first connecting part 241e close to the central axis Q of the electrode terminal and the peripheral surface around the central axis Q of the electrode terminal. The first main body part 241d is connected to the inner circumferential side of the first connecting part 241e, and along the radial direction J of the electrode terminal, the first main body part 241d is closer to the central axis Q of the electrode terminal relative to the first connecting part 241e.

[0294] The first body portion 241d and the first connecting portion 241e can be integrally formed. The first connecting portion 241e is annular, and the first body portion 241d can also be annular to facilitate manufacturing. For example, the first sub-component 241 is stamped from a sheet of material.

[0295] The thickness direction of the first connecting portion 241e is parallel to the thickness direction z of the first wall.

[0296] For ease of description, the dimension indicated by H3 in FIG. 10 is the thickness of the first connecting portion 241e, and the dimension indicated by H5 is the thickness of the first body portion 241d.

[0297] In some embodiments, the first connecting portion 241e can be welded to the first wall 213 so that the first connecting portion 241e is firmly connected to the first wall 213.

[0298] In the thickness direction z of the first wall, the first body portion 241d can partially overlap the second sub-component 242, or the first body portion 241d can fully overlap the second sub-component 242, so that the first body portion 241d can have a larger connection area with the second sub-component 242 to facilitate enhancing the strength of the connector 24 at the first body portion 241d.

[0299] The thickness of the first connecting portion 241e is greater than the thickness of the first body portion 241d. The first connecting portion 241e is thickened relative to the first body portion 241d. When the first connecting portion 241e is welded to the first wall 213, the first connecting portion 241e has a larger connection area with the first wall 213 so that the first connecting portion 241e is firmly connected to the first wall 213.

[0300] In the above scheme, the thickness of the first connecting portion 241e is greater than the thickness of the first body portion 241d. The first sub-component 241 is partially thickened to facilitate welding of the first sub-component 241 to the first wall 213 and to improve the connection reliability of the first sub-component 241 to the first wall 213.

[0301] Referring to FIGS. 9 and 10, according to some embodiments of the present application, in the radial direction J of the electrode terminal, the width of the first connecting portion 241e is greater than or equal to 0.5 mm and less than or equal to 3 mm.

[0302] The first connecting portion 241e is annular, and the center of the first connecting portion 241e can coincide with the central axis Q of the electrode terminal.

[0303] The width of the first connecting portion 241e refers to the width of the annular structure formed by the first connecting portion 241e, for example, the value obtained by subtracting the radius of the inner periphery from the radius of the outer periphery of the annular structure. For ease of description, the dimension indicated by K in FIG. 10 is the width of the first connecting portion 241e.

[0304] Optionally, the width of the first connecting portion 241e can be any one of 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3 mm or a range between any two of them.

[0305] In the above scheme, the width of the first connecting portion 241e satisfies the above relationship, on the one hand, facilitating the welding of the first connecting portion 241e and the first wall 213; on the other hand, the first connecting portion 241e occupies a smaller space in the radial direction J of the electrode terminal, the size of the second sub-component 242 can be larger, and the connecting piece 24 has higher overall strength.

[0306] Please refer to FIG. 9 and FIG. 10, according to some embodiments of the present application, along the thickness direction z of the first wall, the first connecting portion 241e is in direct contact with the first wall 213.

[0307] In the thickness direction z of the first wall, the surface of the first connecting portion 241e closest to the electrode assembly 22 is in direct contact with the first wall 213, and the first connecting portion 241e has a larger thickness, so that the connecting area of the first connecting portion 241e with the first wall 213 in the thickness direction z of the first wall is larger, facilitating the connection of the first connecting portion 241e and the first wall 213.

[0308] For example, when the first connecting portion 241e is welded with the first wall 213, the welding penetration of the first connecting portion 241e and the first wall 213 can be deeper, so that the first connecting portion 241e is firmly connected with the first wall 213.

[0309] In the above scheme, the first connecting portion 241e is in direct contact with the first wall 213 in the thickness direction z of the first wall, facilitating the welding of the first connecting portion 241e and the first wall 213, so that the first connecting portion 241e is firmly connected with the first wall 213.

[0310] Please refer to FIG. 9 and FIG. 10, according to some embodiments of the present application, a first step surface 241f is formed between the first connecting portion 241e and the first main body portion 241d, the second sub-component 242 is stacked with the first main body portion 241d, and the outer circumferential surface of the second sub-component 242 is fitted with the first step surface 241f.

[0311] There is a thickness difference between the first connecting portion 241e and the first main body portion 241d to form the first step surface 241f at the connection of the first connecting portion 241e and the first main body portion 241d.

[0312] In some embodiments, a first stepped surface 241f is formed on the side of the first sub-component 241 facing the electrode assembly 22, and the second sub-component 242 is located on the side of the first sub-component 241 facing the electrode assembly 22 along the thickness direction z of the first wall.

[0313] The connection mode of the second sub-component 242 and the first main body portion 241d can be various, for example, the second sub-component 242 and the first main body portion 241d are matched in profile, the second sub-component 242 and the first main body portion 241d are press-fit connected, or the second sub-component 242 and the first sub-component 241 are connected by adhesive.

[0314] The outer peripheral surface of the second sub-component 242 refers to the peripheral surface of the second sub-component 242 away from the central axis Q of the electrode terminal in the radial direction J of the electrode terminal.

[0315] The outer peripheral surface of the second sub-component 242 and the first stepped surface 241f are in contact refers to that most of the outer peripheral surface of the second sub-component 242 is in contact with the first stepped surface 241f, and when there is a machining error in the outer peripheral surface of the second sub-component 242, there is a gap between the local area of the outer peripheral surface of the second sub-component 242 and the first stepped surface 241f.

[0316] The outer peripheral surface of the second sub-component 242 and the first stepped surface 241f are in contact, and the thickness of the corresponding area of the second sub-component 242 and the first main body portion 241d can be thicker, so as to improve the overall strength of the connecting piece 24.

[0317] In the above scheme, the outer peripheral surface of the second sub-component 242 and the first stepped surface 241f are in contact, so as to facilitate the assembly of the first sub-component 241 and the second sub-component 242, and the connecting piece 24 can have higher overall strength.

[0318] Please refer to FIG. 11 and FIG. 12, FIG. 11 is a cross-sectional view of the assembly state of the first sub-component and the second sub-component provided by some embodiments of the present application, and FIG. 12 is a partial enlarged view of D in FIG. 11. According to some embodiments of the present application, at least a part of the second sub-component 242 is located between the first connecting portion 241e and the first wall 213 along the thickness direction z of the first wall.

[0319] A part of the second sub-component 242 can be located between the first connecting portion 241e and the first wall 213, and another part of the second sub-component 242 can be located between the first main body portion 241d and the first wall 213 along the thickness direction z of the first wall, or all of the second sub-component 242 can be located between the first connecting portion 241e and the first wall 213.

[0320] The second sub-component 242 has a higher hardness, and at least a portion of the second sub-component 242 is located between the first connecting portion 241e and the first wall 213 along the thickness direction z of the first wall. The connecting member 24 has a higher deformation resistance at the first connecting portion 241e, and when the electrode terminal 23 acts on the connecting member 24, the electrode terminal 23 has a better constraint effect, and the risk of damage to the connection between the first connecting portion 241e and the first wall 213 is reduced.

[0321] Please refer to FIG. 11 and FIG. 12. According to some embodiments of the present application, the second sub-component 242 includes a second main body portion 242a and a second connecting portion 242b. The thickness of the second main body portion 242a is greater than the thickness of the second connecting portion 242b. The second connecting portion 242b is located between the first connecting portion 241e and the first wall 213 along the thickness direction z of the first wall. The second main body portion 242a is stacked with the first main body portion 241d. A first step surface 241f is formed between the first connecting portion 241e and the first main body portion 241d. A second step surface 242c is formed between the second main body portion 242a and the second connecting portion 242b. The second step surface 242c is in contact with the first step surface 241f.

[0322] The second main body portion 242a is connected to the inner circumferential side of the second connecting portion 242b. The second main body portion 242a and the second connecting portion 242b are integrally formed, for example, by stamping.

[0323] When the first sub-component 241 and the second sub-component 242 are assembled, the first connecting portion 241e corresponds to the second connecting portion 242b, and the first main body portion 241d corresponds to the second main body portion 242a.

[0324] For ease of description, the dimension indicated by H4 in FIG. 12 is the thickness of the second connecting portion 242b, and the dimension indicated by H6 is the thickness of the second main body portion 242a.

[0325] There is a thickness difference between the first connecting portion 241e and the first main body portion 241d. The side of the first sub-component 241 facing the second sub-component 242 forms a first step surface 241f. There is a thickness difference between the second connecting portion 242b and the second main body portion 242a. The side of the second sub-component 242 facing the first sub-component 241 forms a second step surface 242c.

[0326] When the first sub-component 241 and the second sub-component 242 are stacked, the first connecting portion 241e and the second connecting portion 242b are correspondingly arranged, the first main body portion 241d and the second main body portion 242a are correspondingly arranged, and the second step surface 242c and the first step surface 241f are in contact.

[0327] In some embodiments, the sum of the thickness of the first connecting portion 241e and the thickness of the second connecting portion 242b can be D1, the sum of the thickness of the first main portion 241d and the thickness of the second main portion 242a can be D2, and D1=D2 is satisfied, so as to facilitate the thickness of the connecting piece 24 at any position to be equal.

[0328] In the above scheme, the second main portion 242a and the second connecting portion 242b are connected to each other, the thickness of the second main portion 242a is greater than the thickness of the second connecting portion 242b, so as to facilitate the second connecting portion 242b to cooperate with the first connecting portion 241e. The second step surface 242c is attached to the first step surface 241f, so as to facilitate the second sub-component 242 to be attached to the first sub-component 241, so that the connecting piece 24 has higher overall strength.

[0329] According to some embodiments of the present application, along the thickness direction z of the first wall, the thickness of the first connecting portion 241e is H3, and the thickness of the second connecting portion 242b is H4, and 0.5≤H3 / (H3+H4)≤0.9 is satisfied.

[0330] The first connecting portion 241e and the second connecting portion 242b are arranged in a stacked manner along the thickness direction z of the first wall, the thickness direction of the first connecting portion 241e is parallel to the thickness direction z of the first wall, and the thickness direction of the second connecting portion 242b is parallel to the thickness direction z of the first wall.

[0331] H3 / (H3+H4) can be: in the thickness direction z of the first wall, the thickness proportion of the first connecting portion 241e in the structure after the first connecting portion 241e and the second connecting portion 242b are stacked.

[0332] In the above scheme, the thickness of the first connecting portion 241e and the thickness of the second connecting portion 242b satisfy the above relationship. On the one hand, the thickness of the first connecting portion 241e is thick, so as to improve the welding reliability of the first connecting portion 241e and the first wall 213; on the other hand, the second connecting portion 242b has a certain thickness, the second connecting portion 242b has higher hardness, and the second connecting portion 242b has higher anti-deformation ability after being stacked with the first connecting portion 241e. The connecting piece 24 can have higher overall strength.

[0333] According to some embodiments of the present application, along the thickness direction z of the first wall, the thickness of the first connecting portion 241e is H3, and 0.3mm≤H3≤1.5mm is satisfied.

[0334] The thickness direction of the first connecting portion 241e can be parallel to the thickness direction z of the first wall.

[0335] Optionally, the thickness of the first connecting portion 241e can be any one of 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm or a range between any two of them.

[0336] In the above scheme, the thickness of the first connecting portion 241e satisfies the above relationship, on the one hand, it is convenient for the first connecting portion 241e to be welded to the first wall 213, and on the other hand, the first connecting portion 241e occupies a smaller space in the thickness direction z of the first wall.

[0337] Please refer to FIG. 13, which is a structural schematic diagram of a connecting piece provided in some embodiments of the present application. According to some embodiments of the present application, the connecting piece 24 includes a first portion 24a and a second portion 24b. In the same projection plane perpendicular to the thickness direction z of the first wall, the orthographic projection of the first portion 24a at least partially overlaps the orthographic projection of the electrode terminal 23. The second portion 24b is connected to the outer circumferential side of the first portion 24a. The thickness of the first portion 24a is smaller than the thickness of the second portion 24b.

[0338] The connecting piece 24 can be annular. The first portion 24a is closer to the central axis Q of the electrode terminal relative to the second portion 24b.

[0339] The outer circumferential side of the first portion 24a refers to the side of the first portion 24a away from the central axis Q of the electrode terminal and the peripheral surface surrounding the central axis Q of the electrode terminal.

[0340] For the convenience of description, in FIG. 13, the dimension indicated by H7 is the thickness of the first portion 24a, and the dimension indicated by H8 is the thickness of the second portion 24b.

[0341] In some embodiments, the connecting piece 24 is a bent structure. The connecting piece 24 further includes a third portion 24c. The third portion 24c connects the first portion 24a and the second portion 24b. The second portion 24b is connected to the first wall 213. Along the thickness direction z of the first wall, the first portion 24a can be farther away from the electrode assembly 22 relative to the second portion 24b, so that a part of the second body portion 232 is located between the first portion 24a and the first wall 213.

[0342] After the connecting piece 24 is assembled with the electrode terminal 23, due to the thin thickness of the first portion 24a, the structure of the first portion 24a after being assembled with the electrode terminal 23 occupies a smaller space in the thickness direction z of the first wall, which can reduce the risk of interference between the connecting piece 24 and other components (such as the busbar, the current collecting member, etc.).

[0343] In the above embodiments, the first portion 24a can be provided with the first sub-component 241 and the second sub-component 242, and the thickness of the first portion 24a can be the total thickness of the first sub-component 241 and the second sub-component 242 after being laminated at the first portion 24a; the second portion 24b can be provided with the first sub-component 241 and the second sub-component 242, and the thickness of the second portion 24b can be the total thickness of the first sub-component 241 and the second sub-component 242 after being laminated at the second portion 24b.

[0344] For example, the first sub-component 241 can be of a non-uniform thickness structure, and the thickness of the first sub-component 241 at the first portion 24a can be smaller than the thickness of the first sub-component 241 at the second portion 24b; the second sub-component 242 can be of a uniform thickness structure, and the thickness of the second sub-component 242 at the first portion 24a and the second portion 24b is the same, and after the first sub-component 241 and the second sub-component 242 are laminated, the thickness of the first portion 24a is smaller than the thickness of the second portion 24b.

[0345] Please refer to FIG. 5, FIG. 10, FIG. 12 and FIG. 13, according to some embodiments of the present application, the first sub-component 241 is welded with the first wall 213 to form the first weld 246, and the maximum size of the first weld 246 in the thickness direction z of the first wall is greater than or equal to 0.3 mm.

[0346] When the first sub-component 241 is welded with the first wall 213, the first sub-component 241 and the first wall 213 can be welded on the side of the first wall 213 away from the inside of the battery monomer 20, the first weld 246 extends from the outer surface of the first sub-component 241 towards the electrode assembly 22, and the outer surface of the first sub-component 241 is the surface of the first sub-component 241 away from the electrode assembly 22.

[0347] The maximum size of the first weld 246 refers to the distance between the deepest part of the first weld 246 and the welding surface of the first sub-component 241 in the thickness direction z of the first wall, that is, the penetration of the welding between the first sub-component 241 and the first wall 213. The penetration is one of the important parameters for measuring the quality of welding, which refers to the deepest distance between the molten part of the base material during the welding process.

[0348] In some embodiments, the first weld 246 can not penetrate the first sub-component 241 in the thickness direction z of the first wall, or the first weld 246 can penetrate the first sub-component 241 in the thickness direction z of the first wall, for example, the first weld 246 extends to the first wall 213 or the second sub-component 242 in the thickness direction z of the first wall.

[0349] In some embodiments, the measurement method of the size of the first weld 246 in the thickness direction z of the first wall is as follows: through a CT scanning system, scanning in a direction perpendicular to the thickness direction z of the first wall, obtaining cross-sectional information of the battery cell 20, and measuring the maximum distance between the deepest part of the first weld 246 and the welding surface of the first sub-component. The size is the depth of the first weld 246.

[0350] In the above scheme, the maximum size of the first weld 246 in the thickness direction z of the first wall is greater than 0.3 mm, so that the first sub-component 241 is firmly welded with the first wall 213, and the first sub-component 241 and the first wall 213 have high connection reliability.

[0351] Please refer to FIG. 14, which is a structural schematic diagram of a first wall provided with a reinforcing member according to some embodiments of the present application. According to some embodiments of the present application, the battery cell 20 further comprises a reinforcing member 26, the reinforcing member 26 is fixed to the first wall 213, and the hardness of the reinforcing member 26 is greater than the hardness of the first wall 213; along the thickness direction z of the first wall, a part of the electrode terminal 23 is located between the reinforcing member 26 and the connecting member 24.

[0352] The reinforcing member 26 is a component with high hardness, and the reinforcing member 26 is arranged on the first wall 213, which can increase the overall strength of the first wall 213 and improve the anti-deformation ability of the region of the first wall 213 where the reinforcing member 26 is arranged.

[0353] In some embodiments, along the thickness direction z of the first wall, a part of the second body part 232 is located between the second sub-component 242 and the reinforcing member 26, and the hardness of the second sub-component 242 and the reinforcing member 26 is greater than the hardness of the first wall 213, which can better constrain the electrode terminal 23 on both sides in the thickness direction z of the first wall.

[0354] In some embodiments, the hardness of the reinforcing member 26 can be the same as the hardness of the second sub-component 242, or the hardness of the reinforcing member 26 can be different from the hardness of the second sub-component 242, for example, the hardness of the reinforcing member 26 can be greater than the hardness of the second sub-component 242, or the hardness of the reinforcing member 26 can be less than the hardness of the second sub-component 242.

[0355] The hardness of the reinforcing member 26 is Vickers hardness, and the test method of the hardness of the reinforcing member 26 is as described above.

[0356] In some embodiments, the material of the reinforcing member 26 can be metal, for example, the material of the reinforcing member 26 can include steel, stainless steel, copper, copper alloy, titanium or titanium alloy.

[0357] In some embodiments, the reinforcement 26 can be welded to the first wall 213, or the reinforcement 26 can be adhered to the first wall 213.

[0358] In some embodiments, the first wall 213 can be provided with a recess (e.g., a second groove), and the reinforcement 26 can be embedded in the recess to reduce the space occupied by the reinforcement 26 in the thickness direction z of the first wall after assembly.

[0359] In the above scheme, the reinforcement 26 has a high hardness, and in the thickness direction z of the first wall, the reinforcement 26 cooperates with the connecting piece 24 to clamp the electrode terminal 23 to limit the movement of the electrode terminal 23 relative to the first wall 213.

[0360] Please refer to FIG. 15, which is a schematic view of the welding state of the first sub-component and the first wall according to some embodiments of the present application. In some embodiments, when the reinforcement 26 is arranged between the connecting piece 24 and the first wall 213, after the first sub-component 241 is welded to the first wall 213 to form the first weld 246, the first weld 246 can extend from the first surface 2411 to the first wall 213 in the thickness direction z of the first wall, and the first weld 246 extends to the first wall 213 beyond the reinforcement 26.

[0361] According to some embodiments of the present application, the first sub-component 241 is integrally formed with the first wall 213.

[0362] In some embodiments, the first sub-component 241 and the first wall 213 can be integrally formed by stamping.

[0363] In some embodiments, the first sub-component 241 can be formed on the side of the first wall 213 away from the electrode assembly 22, and the second sub-component 242 is arranged on the first sub-component 241. When the electrode terminal 23 is assembled with the first wall 213, the electrode terminal 23 is first positioned with the first wall 213, and then the first sub-component 241 is bent to make a part of the first sub-component 241 abut against the electrode terminal 23 to fix the electrode terminal 23 to the first wall 213.

[0364] In the above scheme, the first sub-component 241 is integrally formed with the first wall 213, which is convenient for processing and manufacturing, and makes the first sub-component 241 and the first wall 213 have good connection stability.

[0365] Please refer to FIG. 5, according to some embodiments of the present application, the outer surface of the first wall 213 is provided with a first groove 2132, the bottom wall of the first groove 2132 is provided with an electrode lead-out hole 2131, and the electrode terminal 23 covers the electrode lead-out hole 2131; at least a part of the connecting piece 24 is arranged in the first groove 2132, and the first sub-component 241 is welded to the first wall 213.

[0366] The first recess 2132 is a recessed structure formed on the outer surface of the first wall 213, which is the surface of the first wall 213 facing away from the inside of the battery cell 20.

[0367] The electrode lead-out hole 2131 penetrates the first wall 213 in the thickness direction z of the first wall, so as to facilitate the electrical connection between the electrode terminal 23 and the tab 221. For example, a portion of the electrode terminal 23 can be arranged in the electrode lead-out hole 2131 to be connected to the tab 221; or the battery cell 20 further comprises an adapter connecting the electrode terminal 23 and the tab 221, and a portion of the adapter can be arranged in the electrode lead-out hole 2131 to be connected to the electrode terminal 23.

[0368] In some embodiments, a portion of the first sub-component 241 is arranged in the first recess 2132, and the outer circumferential surface of the first sub-component 241 is welded to the inner circumferential surface of the first recess 2132 when the first sub-component 241 is assembled with the first wall 213, so as to firmly connect the first sub-component 241 and the first wall 213. The outer circumferential surface of the first sub-component 241 refers to the circumferential surface of the first sub-component 241 away from the central axis Q of the electrode terminal. The inner circumferential surface of the first recess 2132 connects the outer surface of the first wall 213 and the bottom wall of the first recess 2132, and is arranged around the bottom wall of the first recess 2132.

[0369] In the above scheme, the arrangement of the first recess 2132 can reduce the space occupation of the connecting member 24 in the thickness direction z of the first wall after being connected to the first wall 213.

[0370] According to some embodiments of the present application, the battery cell 20 further comprises a sealing member 27 arranged between the second body portion 232 and the first wall 213 in the thickness direction z of the first wall, so as to seal the connection between the electrode terminal 23 and the first wall 213.

[0371] In the above scheme, the sealing member 27 forms a sealed structure between the electrode terminal 23 and the first wall 213, which can reduce the risk of electrolyte flowing out of the electrode lead-out hole 2131.

[0372] According to some embodiments of the present application, a portion of the electrode terminal 23 is arranged in the electrode lead-out hole 2131, and a portion of the sealing member 27 extends into the electrode lead-out hole 2131, and the sealing member 27 is located between the hole wall of the electrode lead-out hole 2131 and the electrode terminal 23 in the radial direction J of the electrode terminal. The extension of the sealing member 27 into the electrode lead-out hole 2131 can increase the connection area between the sealing member 27 and the electrode terminal 23, so as to improve the sealing performance of the sealing member 27.

[0373] Referring to FIG. 5, according to some embodiments of the present application, the battery cell 20 further comprises a second insulation member 28, which is arranged on a side of the first wall 213 facing the electrode assembly 22, so as to isolate the first wall 213 and the conductive components inside the battery cell 20, and reduce the risk of positive and negative electrode contact short circuit.

[0374] According to some embodiments of the present application, a part of the electrode terminal 23 is arranged in the electrode lead-out hole 2131, a part of the second insulation member 28 extends into the electrode lead-out hole 2131, and along the radial direction J of the electrode terminal 23, the second insulation member 28 is located between the hole wall of the electrode lead-out hole 2131 and the electrode terminal 23. The second insulation member 28 extending into the electrode lead-out hole 2131 can isolate the electrode terminal 23 from the first wall 213, and reduce the risk of positive and negative electrode contact short circuit.

[0375] According to some embodiments of the present application, the embodiments of the present application further provide a battery 100 comprising the battery cell 20 provided by any of the above embodiments.

[0376] According to some embodiments of the present application, the embodiments of the present application further provide a consumer device comprising the battery cell 20 or the battery 100 provided by any of the above embodiments, and the battery cell 20 or the battery 100 is used to provide electric energy.

[0377] The consumer device can be any of the devices or systems using the battery cell 20 or the battery 100.

[0378] According to some embodiments of the present application, referring to FIGS. 3-6 and 8-14, the embodiments of the present application provide a battery cell 20 comprising a housing 21, an electrode assembly 22, an electrode terminal 23, a connecting member 24 and a first insulation member 25.

[0379] The housing 21 comprises a shell 211 and an end cover 212, the shell 211 has an opening, and the end cover 212 covers the opening. The housing 21 comprises a first wall 213, and the electrode terminal 23 is arranged on the first wall 213, and the end cover 212 is the first wall 213. The electrode terminal 23 comprises a first body part 231 and a second body part 232, the second body part 232 is located on a side of the first wall 213 away from the inside of the battery cell 20, the first body part 231 is located on a side of the second body part 232 away from the electrode assembly 22, the diameter of the second body part 232 is greater than the diameter of the first body part 231, and along the radial direction J of the electrode terminal 23, the second body part 232 protrudes from the outer peripheral surface of the first body part 231. The first wall 213 is provided with an electrode lead-out hole 2131, and the second body part 232 covers the electrode lead-out hole 2131.

[0380] The electrode assembly 22 is arranged in the housing 21, and the electrode assembly 22 has a tab 221, and the electrode terminal 23 is electrically connected with the tab 221.

[0381] The connecting piece 24 is located on the side of the first wall 213 facing away from the electrode assembly 22. The connecting piece 24 comprises a first sub-component 241 and a second sub-component 242 connected to each other, both of which are annular and both of which are arranged around the central axis Q of the electrode terminal.

[0382] The first insulating piece 25 is arranged at least partially between the electrode terminal 23 and the connecting piece 24. The connecting piece 24 has a through hole 245 in which a portion of the first insulating piece 25 and a portion of the electrode terminal 23 are accommodated, and the first insulating piece 25 is located between the electrode terminal 23 and the connecting piece 24 in the radial direction J of the electrode terminal.

[0383] The melting point of the first sub-component 241 is greater than or equal to 500°C and less than or equal to 1000°C, the melting point of the second sub-component 242 is greater than or equal to 1050°C and less than or equal to 3500°C, and the melting point of the first wall 213 is greater than or equal to 500°C and less than or equal to 1000°C. The material of the second sub-component 242 is different from that of the first sub-component 241, the melting point of the second sub-component 242 is greater than that of the first sub-component 241, and the second sub-component 242 is connected to the first sub-component 241 by friction welding. The material of the first sub-component 241 is the same as that of the first wall 213, the melting point of the first sub-component 241 is the same as that of the first wall 213, and the first sub-component 241 is laser welded to the first wall 213.

[0384] The first sub-component 241 is a bent structure, and comprises a first segment 241a, a second segment 241b, and a third segment 241c. The third segment 241c is welded to the first wall 213, the second segment 241b is located on the inner circumferential side of the third segment 241c, and the second segment 241b is farther away from the electrode assembly 22 than the third segment 241c in the thickness direction z of the first wall. The first segment 241a connects the second segment 241b and the third segment 241c, and the first sub-component 241 is integrally formed.

[0385] The second sub-component 242 is located on the side of the first sub-component 241 facing the electrode assembly 22, and the second sub-component 242 is also a bent structure. The second sub-component 242 has a similar structure profile to the first sub-component 241, and the third segment 241c, the second segment 241b, and the first segment 241a all overlap the second sub-component 242 in the thickness direction z of the first wall. The first sub-component 241 and the second sub-component 242 are arranged in a stacked manner. The hardness of the second sub-component 242 is greater than that of the first sub-component 241. In the stacking direction, the thickness of the second sub-component 242 is less than that of the first sub-component 241, so that the overall thickness of the connecting piece 24 can be smaller and occupy less assembly space.

[0386] According to the battery cell 20 of the embodiment of the present application, the second sub-component 242 has a higher hardness, and after the second sub-component 242 cooperates with the first sub-component 241, the connecting piece 24 has a higher anti-deformation capability. The connecting piece 24 cooperates with the first wall 213 to clamp the second body part 232 of the electrode terminal 23, and can have a higher limiting effect on the electrode terminal 23 in the thickness direction z of the first wall, so as to constrain the electrode terminal 23 from moving in the thickness direction z of the first wall, so that the electrode terminal 23 is stably connected with other components (such as a transition piece or a tab 221), and the reliability of the battery cell 20 is improved. Meanwhile, the melting point of the second sub-component 242 is different from the melting point of the first sub-component 241, and the second sub-component 242 is connected with the first sub-component 241 through friction welding, so that the second sub-component 242 is firmly connected with the first sub-component 241; the first sub-component 241 is laser welded with the first wall 213, the welding quality is high, and the first sub-component 241 has small deformation after welding.

[0387] Although the present application has been described with reference to the preferred embodiments, various modifications can be made to the present application and equivalents thereof without departing from the scope of the present application. In particular, the technical features mentioned in each of the embodiments can be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

A battery cell comprises: a housing comprising a first wall; an electrode assembly disposed in the housing, the electrode assembly comprising a tab; an electrode terminal disposed on the first wall, the electrode terminal being electrically connected to the tab; a connecting member at least partially disposed on an outer periphery of the electrode terminal, the connecting member being configured to secure the electrode terminal to the first wall; wherein the connecting member is connected to the first wall, and the connecting member comprises a first sub-member and a second sub-member connected to each other, the first sub-member being connected to the first wall, and the second sub-member having a hardness greater than that of the first sub-member. The battery cell of claim 1, wherein, The first sub-member has a melting point greater than or equal to 500°C and less than or equal to 1000°C. The second sub-member has a melting point greater than or equal to 1050°C and less than or equal to 3500°C. The first wall has a melting point greater than or equal to 500°C and less than or equal to 1000°C. The battery cell according to claim 1 or 2, wherein, The first sub-component has a hardness greater than or equal to 30 kgf / mm 2 and less than or equal to 170 kgf / mm 2 ; The hardness of the second sub-component is greater than or equal to 100 kgf / mm 2 and less than or equal to 500 kgf / mm 2 . The battery cell of any one of claims 1-3, wherein, The first sub-member has the same material as the first wall. The battery cell of any one of claims 1-4, wherein, The first sub-member has the same base metal as the second sub-member. The battery cell of any one of claims 1-5, wherein, The first sub-member is laser-welded to the first wall. The battery cell of any one of claims 1-6, wherein, The first sub-member comprises aluminum or an aluminum alloy, and the second sub-member comprises steel, stainless steel, copper, a copper alloy, titanium, or a titanium alloy. The battery cell of any one of claims 1-6, wherein, The first sub-member comprises steel or stainless steel, and the second sub-member comprises titanium or a titanium alloy. The battery cell of any one of claims 1-6, wherein, The second sub-member comprises ceramic, a polymer plastic, or a carbon fiber reinforced composite material. The battery cell of any one of claims 1-9, wherein, The first sub-member is welded to the first wall to form a first weld, the first sub-member has a first surface facing away from the electrode assembly, and the first weld extends from the first surface to the first wall in a thickness direction of the first wall. The battery cell of any one of claims 1-10, wherein, In the same projection plane perpendicular to the thickness direction of the first wall, an orthographic projection of the second sub-member at least partially overlaps an orthographic projection of the electrode terminal. The battery cell of any one of claims 1-11, wherein, The first sub-member comprises a first section connected to the first wall and a second section located on an inner periphery side of the first section, the second section being farther from the electrode assembly than the first wall in the thickness direction of the first wall, and the second section at least partially overlaps the second sub-member in the thickness direction of the first wall. The battery cell of claim 12, wherein, The first section at least partially overlaps the second sub-member in the thickness direction of the first wall. The battery cell according to claim 12 or 13, wherein The first sub-member further comprises a third section, the first section connects the first wall through the third section, the first section is located on an inner periphery side of the third section, the second section is farther from the electrode assembly than the third section in the thickness direction of the first wall, and the first section connects the second section and the third section. The battery cell of claim 14, wherein, The third section at least partially overlaps the second sub-member in the thickness direction of the first wall. The battery cell according to claim 14 or 15, wherein The second sub-member comprises a first reinforcing section laminated with the first section and a second reinforcing section laminated with the second section, and the first reinforcing section is connected to the second reinforcing section. The battery cell of claim 16, wherein, The second sub-member further comprises a third reinforcing section laminated with the third section, and the third reinforcing section is connected to the first reinforcing section. The battery cell of any one of claims 1-17, wherein, The second sub-component is disposed around the electrode terminal. The battery cell of any one of claims 1-18, wherein, The first sub-component and the second sub-component at least partially overlap in plan view in the same projection plane perpendicular to the thickness direction of the first wall. The battery cell of claim 19, wherein, The first sub-component and the second sub-component completely overlap in plan view in the same projection plane perpendicular to the thickness direction of the first wall. The battery cell according to claim 19 or 20, wherein The second sub-component is located on the side of the first sub-component facing the electrode assembly in the thickness direction of the first wall. The battery cell of claim 19, wherein, The second sub-component is located on the side of the first sub-component facing away from the electrode assembly in the thickness direction of the first wall. The first sub-component and the first wall form a fixed portion, and the second sub-component does not overlap with the fixed portion. The battery cell of any one of claims 1-22, wherein, The first sub-component and the second sub-component are both disposed around the electrode terminal. The battery cell of any one of claims 1-23, wherein, The battery monomer further comprises a first insulating member, which is at least partially disposed between the electrode terminal and the connecting member. The connecting member has a through hole, and a portion of the first insulating member and a portion of the electrode terminal are accommodated in the through hole. The battery cell of any one of claims 1-24, wherein, The first sub-component and the second sub-component are stacked, and at least part of the thickness of the second sub-component is smaller than the thickness of the first sub-component in the stacking direction. The battery cell of claim 25, wherein, The thickness of the first sub-component is H1, and the thickness of the second sub-component is H2, satisfying 0.5≤H1 / (H1+H2)≤0.

9. The battery cell of any one of claims 1-26, wherein, The first sub-component includes a first main body portion and a first connecting portion, the first connecting portion is annular, the first main body portion is connected to the inner circumferential side of the first connecting portion, the first connecting portion is connected to the first wall, the first main body portion at least partially overlaps with the second sub-component in the thickness direction of the first wall, and the thickness of the first connecting portion is greater than the thickness of the first main body portion. The battery cell of claim 27, wherein In the radial direction of the electrode terminal, the width of the first connecting portion is greater than or equal to 0.5 mm and less than or equal to 3 mm. The battery cell of claim 27, wherein, In the thickness direction of the first wall, the first connecting portion is in direct contact with the first wall. The battery cell of claim 29, wherein, A first step surface is formed between the first connecting portion and the first main body portion, the second sub-component is stacked with the first main body portion, and the outer circumferential surface of the second sub-component is fitted with the first step surface. The battery cell of claim 27, wherein, In the thickness direction of the first wall, at least part of the second sub-component is located between the first connecting portion and the first wall. The battery cell of claim 31, wherein, The second sub-component includes a second main body portion and a second connecting portion, the thickness of the second main body portion is greater than the thickness of the second connecting portion. In the thickness direction of the first wall, the second connecting portion is located between the first connecting portion and the first wall. The second main body portion is stacked with the first main body portion, a first step surface is formed between the first connecting portion and the first main body portion, a second step surface is formed between the second main body portion and the second connecting portion, and the second step surface is fitted with the first step surface. The battery cell of claim 32, wherein, In the thickness direction of the first wall, the thickness of the first connecting part is H3, and the thickness of the second connecting part is H4, satisfying 0.5≤H3 / (H3+H4)≤0.

9. The battery cell of claim 27, wherein, In the thickness direction of the first wall, the thickness of the first connecting part is H3, satisfying 0.3mm≤H3≤1.5mm. The battery cell of any one of claims 1-34, wherein, The connecting part includes a first part and a second part, and a normal projection of the first part at least partially overlaps a normal projection of the electrode terminal on the same projection plane perpendicular to the thickness direction of the first wall. The second part is connected to the outer circumferential side of the first part, and the thickness of the first part is smaller than the thickness of the second part. The battery cell of any one of claims 1-35, wherein, The first sub-component is welded to the first wall to form a first weld, and in the thickness direction of the first wall, the maximum dimension of the first weld is greater than or equal to 0.3mm. The battery cell of any one of claims 1-36, wherein, The battery cell further includes a reinforcing part fixed to the first wall, and the hardness of the reinforcing part is greater than the hardness of the first wall. In the thickness direction of the first wall, a part of the electrode terminal is located between the reinforcing part and the connecting part. The battery cell of any one of claims 1-5, wherein, The first sub-component is integrally formed with the first wall. The battery cell of any one of claims 1-38, wherein, The connecting part is located on the side of the first wall away from the electrode assembly. The battery cell of any one of claims 1-39, wherein, An outer surface of the first wall is provided with a first groove, a bottom wall of the first groove is provided with an electrode lead-out hole, and the electrode terminal covers the electrode lead-out hole. At least a part of the connecting part is arranged in the first groove, and the first sub-component is welded to the first wall. A battery including the battery cell according to any one of claims 1-40. An electrical device including the battery cell according to any one of claims 1-40 or the battery according to claim 41, the battery cell or the battery being used to provide electrical energy.

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