Battery cell, battery, energy storage device, and electric device

Abstract

A battery cell (20), a battery (100), an energy storage device (2000), and an electric device. The battery cell (20) comprises an electrode assembly (22), a casing (21), an electrode terminal (23), a first connecting member (24), and a deformable member (25). The casing (21) comprises a first wall body (211). The electrode terminal (23) is arranged on the first wall body (211). The first connecting member (24) is connected to the first wall body (211). The material of the first connecting member (24) is different from that of the first wall body (211). The deformable member (25) is connected to the first connecting member (24). The material of the deformable member (25) is the same as that of the first connecting member (24). The deformable member (25) is configured to be deformable so as to be in contact with the electrode terminal (23), so that the first wall body (211) is electrically connected to the electrode terminal (23).

Description

Battery cell, battery, energy storage device and electric device

[0001] Cross-reference to related applications

[0002] This application is based on Chinese Patent Application No. 202410845862.8, filed on June 27, 2024, entitled "Battery cell, battery, energy storage device and electric device", which is incorporated by reference in its entirety. TECHNICAL FIELD

[0003] The present application relates to the technical field of batteries, in particular to a battery cell, a battery, an energy storage device and an electric device. BACKGROUND

[0004] With the rapid development of new energy technology, new energy products such as energy storage devices and electric vehicles are widely used. For new energy products, battery technology is an important factor for their development.

[0005] A battery generally includes a battery cell. In the development of battery technology, how to improve the safety performance of the battery cell is a technical problem that needs to be solved in the battery technology.

[0006] SUMMARY

[0007] One of the purposes of the embodiments of the present application is to provide a battery cell, a battery, an energy storage device and an electric device, which aims to solve the technical problem of poor safety performance of the battery cell in the related art.

[0008] To solve the above technical problem, the technical solution adopted by the embodiments of the present application is to provide a battery cell, which includes:

[0009] An electrode assembly;

[0010] A housing for accommodating the electrode assembly, the housing including a first wall body;

[0011] An electrode terminal for electrically connecting the electrode assembly, the electrode terminal being disposed on the first wall body;

[0012] A first connecting member connected to the first wall body, the material of the first connecting member being different from that of the first wall body;

[0013] A deformable member connected to the first connecting member, the material of the deformable member being the same as that of the first connecting member, the deformable member being configured to be deformable to contact the electrode terminal, so as to electrically connect the first wall body and the electrode terminal.

[0014] The battery monomer provided by the embodiments of the present application has the beneficial effects that the first connecting piece in the battery monomer is connected with the first wall body, and the deformable piece is connected with the first connecting piece. Since the material of the deformable piece is the same as that of the first connecting piece, the material characteristics of the deformable piece are also the same as those of the first connecting piece. The material state change difference of the deformable piece and the first connecting piece under the influence of environmental factors such as temperature and air pressure is effectively reduced, the connection reliability of the deformable piece and the first connecting piece is effectively improved, the risk of a gap occurring at the connection between the deformable piece and the first connecting piece is reduced, the situation of gas generated by the electrode assembly leaking outward from the connection between the deformable piece and the first connecting piece is improved, the working reliability of the deformable piece is effectively improved, and the safety performance of the battery monomer is effectively improved.

[0015] In some embodiments of the present application, the first connecting piece includes a first clamping portion, a second clamping portion, and a first connecting portion, the first connecting portion is connected between the first clamping portion and the second clamping portion, and the first clamping portion and the second clamping portion cooperate to clamp the first wall body.

[0016] By adopting the above technical solution, the connection reliability of the first wall body and the first connecting piece is effectively improved, the connection tightness of the first wall body and the first connecting piece is increased, the risk of a gap occurring at the connection between the first wall body and the first connecting piece is reduced, the situation of gas generated by the electrode assembly leaking outward from the connection between the first wall body and the first connecting piece is improved, the working reliability of the deformable piece is further improved, and the safety performance of the battery monomer is further improved.

[0017] In some embodiments of the present application, the first wall body is provided with a connecting hole, the connecting hole penetrates through the first wall body along the opposite sides in the thickness direction, and the first clamping portion and the second clamping portion cooperate to clamp the hole rim of the connecting hole.

[0018] By adopting the above technical solution, the first wall body and the first connecting piece are conveniently connected, and the connection reliability of the first wall body and the first connecting piece is effectively improved.

[0019] In some embodiments of the present application, the first connecting piece is provided with a first via hole, the first via hole penetrates through the first connecting piece along the opposite sides in the thickness direction of the first wall body, and the deformable piece is configured to be deformable to contact the electrode terminal through the first via hole.

[0020] By adopting the above technical solution, the deformable piece and the electrode terminal are conveniently contacted in the case that the internal pressure of the battery monomer reaches a threshold value.

[0021] In some embodiments of the present application, the deformable piece includes a second connecting portion and a deformation portion, the second connecting portion is connected with the first connecting piece, and the deformation portion is configured to be deformable to contact the electrode terminal through the first via hole.

[0022] By adopting the technical scheme, the deformable member and the first connecting member are conveniently connected, and the deformable member and the electrode terminal are conveniently contacted when the internal pressure of the battery cell reaches the threshold value.

[0023] In some embodiments of the present application, the second connecting portion is arranged around the deformation portion and the first via hole.

[0024] By adopting the technical scheme, the second connecting portion and the first connecting member can be connected along the circumferential direction of the second connecting portion, so that a sealing boundary around the first via hole is formed between the deformable member and the first connecting member, which not only effectively seals the first via hole, but also further improves the connection reliability of the deformable member and the first connecting member.

[0025] In some embodiments of the present application, the distance between the deformation portion and the electrode terminal along the thickness direction of the first wall body is 0.2mm-1.5mm.

[0026] By adopting the technical scheme, not only is there sufficient insulation distance between the deformable member and the electrode terminal, thereby reducing the risk of short circuit failure of the battery cell caused by accidental contact between the deformable member and the electrode terminal when the battery cell is in a normal working state, but also the action stroke of the deformable member is not too large, so that the deformable member can timely contact the electrode terminal when the internal pressure of the battery cell reaches the threshold value, thereby effectively improving the safety performance of the battery cell.

[0027] In some embodiments of the present application, the contact area between the deformable member and the electrode terminal is 20mm 2 -500mm 2 .

[0028] By adopting the technical scheme, not only is there sufficient flow area between the deformable member and the electrode terminal, so that the fuse can be fused after the short-circuit current flows through the fuse, thereby cutting off the charging and discharging circuit of the battery cell, but also the contact area between the deformable member and the electrode terminal is limited, thereby reducing the space occupied by the protection structure formed by the deformable member and the electrode terminal, thereby optimizing the volume energy density of the battery cell.

[0029] In some embodiments of the present application, the battery cell further comprises a first sealing member arranged between the first wall body and the first connecting member to seal and connect the first wall body and the first connecting member.

[0030] By adopting the technical scheme, the sealing effect of the connection between the first wall body and the first connecting member is effectively improved, the leakage of the gas generated by the electrode assembly from the connection between the first wall body and the first connecting member is improved, the working reliability of the deformable member is further improved, and the safety performance of the battery cell is further improved.

[0031] In some embodiments of the present application, the first wall body has a first sealing surface, the first connecting piece has a second sealing surface, the first sealing surface and the second sealing surface cooperate to hold the first sealing piece, and the compression rate of the first sealing piece in the direction from the first sealing surface to the second sealing surface is 2%-50%.

[0032] By adopting the above technical solutions, not only the sealing effect of the connection between the first wall body and the first connecting piece is effectively improved, but also the risk of rupture of the first sealing piece caused by excessive pressure is reduced, and the reliability of the first sealing piece is effectively improved.

[0033] In some embodiments of the present application, the electrode terminal includes a terminal body, a first limiting structure is arranged between the terminal body and the first connecting piece, and the first limiting structure is used to limit the relative position of the terminal body and the first connecting piece in a preset direction, and the preset direction is not parallel to the thickness direction of the first wall body.

[0034] By adopting the above technical solutions, the relative position of the terminal body and the first connecting piece in the preset direction is effectively limited, thereby effectively reducing the risk of displacement of the terminal body in the preset direction.

[0035] In some embodiments of the present application, a first limiting groove is arranged on the side of the terminal body facing the electrode assembly, the first connecting piece includes a first limiting part, and at least part of the first limiting part is arranged in the first limiting groove to form the first limiting structure.

[0036] By adopting the above technical solutions, the first limiting structure is effectively simplified, and the relative position of the terminal body and the first connecting piece in the preset direction is facilitated to be limited.

[0037] In some embodiments of the present application, the first limiting part is protruded on the side of the first wall body away from the electrode assembly, and the depth of the first limiting groove is greater than or equal to the protrusion height of the first limiting part from the side of the first wall body away from the electrode assembly.

[0038] By adopting the above technical solutions, the part of the first limiting part protruding from the side of the first wall body away from the electrode assembly is accommodated in the first limiting groove, the situation that the terminal body is lifted by the first limiting part is effectively improved, the terminal body and the first wall body can be abutted with each other, and the battery monomer is facilitated to be assembled.

[0039] In some embodiments of the present application, the difference between the depth of the first limiting groove and the protrusion height of the first limiting part from the side of the first wall body away from the electrode assembly is 0mm-0.5mm.

[0040] By adopting the above technical solutions, not only the situation that the terminal body is lifted by the first limiting part is effectively improved, but also the depth of the first limiting groove is optimized, and the terminal body has sufficient structural strength.

[0041] In some embodiments of the present application, the terminal body comprises a conductive piece and a first insulating piece, the deformable piece is configured to be deformable to contact the conductive piece, the first insulating piece is arranged between the conductive piece and the first wall body, and the first limiting structure is arranged between the first insulating piece and the first connecting piece.

[0042] By adopting the above technical solution, the first limiting structure is conveniently arranged on the terminal body.

[0043] In some embodiments of the present application, a second limiting structure is arranged between the conductive piece and the first insulating piece, and the second limiting structure is used to limit the relative position of the conductive piece and the first insulating piece along a preset direction.

[0044] By adopting the above technical solution, not only is the relative position of the first connecting piece and the first insulating piece along the preset direction limited by the first limiting structure, but also the relative position of the first insulating piece and the conductive piece along the preset direction is limited by the second limiting structure, thereby further reducing the risk of displacement of the terminal body along the preset direction.

[0045] In some embodiments of the present application, a second limiting groove is concavely arranged on the side of the conductive piece facing the first insulating piece, the first insulating piece comprises a first insulating body and a second limiting part, the first insulating body is arranged between the conductive piece and the first wall body, and at least part of the second limiting part is arranged in the second limiting groove to form the second limiting structure.

[0046] By adopting the above technical solution, the second limiting structure is effectively simplified, and the relative position of the first insulating piece and the conductive piece along the preset direction is conveniently limited.

[0047] In some embodiments of the present application, the second limiting part is protrudingly arranged on the side of the first insulating body away from the electrode assembly, and the depth of the second limiting groove is greater than or equal to the protruding height of the second limiting part from the side of the first insulating body away from the electrode assembly.

[0048] By adopting the above technical solution, the second limiting part is entirely accommodated in the first limiting groove, the situation that the conductive piece is lifted by the second limiting part is effectively improved, the conductive piece and the first insulating body can abut against each other, and the battery monomer is conveniently assembled.

[0049] In some embodiments of the present application, the difference between the depth of the second limiting groove and the protruding height of the second limiting part from the side of the first insulating body away from the electrode assembly is 0mm-0.5mm.

[0050] By adopting the above technical solution, not only is the situation that the conductive piece is lifted by the second limiting part effectively improved, but also the depth of the second limiting groove is optimized, and the conductive piece has sufficient structural strength.

[0051] In some embodiments of the present application, the electrode terminal further comprises a second connecting member, and the terminal body is connected to the first wall body through the second connecting member.

[0052] By adopting the above technical solution, the terminal body and the first wall body are conveniently connected.

[0053] In some embodiments of the present application, the second connecting member comprises a third clamping portion, a fourth clamping portion and a third connecting portion, the third connecting portion is connected between the third clamping portion and the fourth clamping portion, and the third clamping portion and the fourth clamping portion cooperate to clamp the terminal body and the first wall body.

[0054] By adopting the above technical solution, the connection reliability of the terminal body and the first wall body is effectively improved.

[0055] In some embodiments of the present application, the first connecting member is provided with a third limiting groove, and at least part of the deformable member is arranged in the third limiting groove and connected to the first connecting member.

[0056] By adopting the above technical solution, the relative position of the deformable member and the first connecting member is effectively limited, the risk of gap at the connection between the deformable member and the first connecting member is further reduced, the working reliability of the deformable member is further improved, and the safety performance of the battery monomer is further improved.

[0057] In some embodiments of the present application, the deformable member is welded to the first connecting member.

[0058] By adopting the above technical solution, since the material of the deformable member is the same as that of the first connecting member, the melting part of the deformable member can be better combined with the melting part of the first connecting member during welding, thereby further improving the connection reliability of the deformable member and the first connecting member.

[0059] In some embodiments of the present application, the battery monomer comprises two deformable members and two electrode terminals with opposite polarities, the two electrode terminals are arranged in an insulating manner with the first wall body, and the two electrode terminals are arranged in a one-to-one corresponding manner with the two deformable members.

[0060] By adopting the above technical solution, the safety performance of the battery monomer is further improved.

[0061] In some embodiments of the present application, the first wall body is provided with a pressure relief hole, the pressure relief hole penetrates through opposite sides of the first wall body along the thickness direction, the battery monomer further comprises a third connecting member and a pressure relief mechanism, the third connecting member is connected to the first wall body, the material of the third connecting member is different from that of the first wall body, the pressure relief mechanism is arranged in the pressure relief hole and connected to the third connecting member, and the material of the pressure relief mechanism is the same as that of the third connecting member.

[0062] By adopting the technical scheme, since the material of the pressure relief mechanism is the same as that of the third connecting piece, the material characteristics of the pressure relief mechanism are also the same as those of the third connecting piece, the difference in material state change of the pressure relief mechanism and the third connecting piece under the influence of environmental factors such as temperature and air pressure is effectively reduced, the connection reliability of the pressure relief mechanism and the third connecting piece is effectively improved, the risk of a gap occurring at the connection of the pressure relief mechanism and the third connecting piece is effectively reduced, the working reliability of the deformable member and the pressure relief mechanism is effectively improved, and the safety performance of the battery monomer is further improved.

[0063] In some embodiments of the present application, the third connecting piece includes a fifth clamping portion, a sixth clamping portion, and a fourth connecting portion connected between the fifth clamping portion and the sixth clamping portion, and the fifth clamping portion and the sixth clamping portion clamp the hole rim of the pressure relief hole in cooperation.

[0064] By adopting the technical scheme, the connection reliability of the first wall body and the third connecting piece is effectively improved, the connection tightness of the first wall body and the third connecting piece is increased, the risk of a gap occurring at the connection of the first wall body and the third connecting piece is reduced, the situation of gas generated by the electrode assembly leaking outward from the connection of the first wall body and the third connecting piece is improved, the working reliability of the deformable member and the pressure relief mechanism is further improved, and the safety performance of the battery monomer is further improved.

[0065] In some embodiments of the present application, the third connecting piece is provided with a second through hole penetrating through opposite sides of the third connecting piece along the thickness direction of the first wall body, and the pressure relief mechanism cover is arranged in the second through hole.

[0066] By adopting the technical scheme, the gas generated by the electrode assembly can be discharged to the external environment of the battery monomer when the internal pressure of the battery monomer reaches a threshold value.

[0067] In some embodiments of the present application, the third connecting piece is provided with a fourth limiting groove, and at least part of the pressure relief mechanism is arranged in the fourth limiting groove and connected with the third connecting piece.

[0068] By adopting the technical scheme, the relative position of the pressure relief mechanism and the third connecting piece is effectively limited, the risk of a gap occurring at the connection of the pressure relief mechanism and the third connecting piece is further reduced, the working reliability of the deformable member and the pressure relief mechanism is further improved, and the safety performance of the battery monomer is further improved.

[0069] In some embodiments of the present application, the depth of the fourth limiting groove is greater than or equal to the thickness of the pressure relief mechanism.

[0070] By adopting the technical scheme, the pressure relief mechanism can be entirely arranged in the fourth limiting groove, so that the pressure relief mechanism does not protrude outward from the fourth limiting groove, thereby effectively reducing the risk of damage caused by interference between the pressure relief mechanism and other components of the battery monomer, and further improving the safety performance of the battery monomer.

[0071] In some embodiments of the present application, the difference between the depth of the fourth limiting groove and the thickness of the pressure relief mechanism is 0mm-0.5mm.

[0072] By adopting the technical scheme, the depth of the fourth limiting groove can be optimized without the pressure relief mechanism protruding outward from the fourth limiting groove, thereby effectively improving the structural strength of the third connecting piece.

[0073] In some embodiments of the present application, the battery monomer further comprises a second sealing piece arranged between the first wall body and the third connecting piece to seal the connection between the first wall body and the third connecting piece.

[0074] By adopting the technical scheme, the sealing effect of the connection between the first wall body and the third connecting piece is effectively improved, the leakage of gas generated by the electrode assembly from the connection between the first wall body and the third connecting piece is improved, the working reliability of the deformable piece and the pressure relief mechanism is further improved, and the safety performance of the battery monomer is further improved.

[0075] In some embodiments of the present application, the first wall body has a third sealing surface, the third connecting piece has a fourth sealing surface, the third sealing surface and the fourth sealing surface cooperate to clamp the second sealing piece, and the compression rate of the second sealing piece in the direction from the third sealing surface to the fourth sealing surface is 2%-50%.

[0076] By adopting the technical scheme, not only is the sealing effect of the connection between the first wall body and the third connecting piece effectively improved, but also the risk of rupture of the second sealing piece due to excessive pressure is reduced, and the reliability of the second sealing piece is effectively improved.

[0077] In some embodiments of the present application, the pressure relief mechanism is welded to the third connecting piece.

[0078] By adopting the technical scheme, since the material of the pressure relief mechanism is the same as that of the third connecting piece, the melted part of the pressure relief mechanism can be better combined with the melted part of the third connecting piece during welding, thereby further improving the connection reliability of the pressure relief mechanism and the third connecting piece.

[0079] In some embodiments of the present application, the third connecting piece is made of aluminum alloy.

[0080] By adopting the technical scheme, the connection reliability of the pressure relief mechanism and the third connecting piece is effectively improved.

[0081] In some embodiments of the present application, the battery monomer further comprises a protective sheet, which is arranged on the side of the first wall body away from the electrode assembly and covers the pressure relief hole.

[0082] By adopting the above technical solution, foreign matters such as electrolyte and dust can be blocked from entering the pressure relief hole, reducing the adverse effects of foreign matters on the pressure relief mechanism, thereby further improving the safety performance of the battery monomer.

[0083] In some embodiments of the present application, the protective sheet is bonded to the first wall body.

[0084] By adopting the above technical solution, the protective sheet can be fixed on the first wall body.

[0085] In some embodiments of the present application, the shell comprises a shell body and a cover body covering the shell body, the cover body constitutes the first wall body, the first wall body is connected with the shell body, and the material of the first wall body is the same as that of the shell body.

[0086] By adopting the above technical solution, since the material of the first wall body is the same as that of the shell body, the material properties of the first wall body are also the same as those of the shell body, effectively reducing the difference in material state changes of the first wall body and the shell body under the influence of environmental factors such as temperature and air pressure, thereby effectively improving the connection reliability of the first wall body and the shell body, effectively reducing the risk of gaps at the connection between the first wall body and the shell body, and further improving the safety performance of the battery monomer.

[0087] In some embodiments of the present application, the shell body and the first wall body are welded.

[0088] By adopting the above technical solution, since the material of the first wall body is the same as that of the shell body, the melted part of the first wall body can be better combined with the melted part of the shell body during welding, thereby further improving the connection reliability of the first wall body and the shell body.

[0089] In some embodiments of the present application, the first connecting member is made of aluminum alloy, and the first wall body is made of steel.

[0090] By adopting the above technical solution, not only the connection reliability of the deformable member and the first connecting member is improved, but also the structural strength of the first wall body is improved.

[0091] In some embodiments of the present application, the battery monomer further comprises a second insulating member arranged on the side of the first wall body facing the electrode assembly, the second insulating member comprises a second insulating body and a first blocking portion connected to the second insulating body, and the first blocking portion is arranged opposite to the deformable member.

[0092] By adopting the technical scheme, the deformable part is effectively protected, and the risk of damage of the deformable part to other components of the battery cell is effectively reduced.

[0093] In some embodiments of the present application, the first barrier portion is provided with a first air hole for allowing gas to flow from the electrode assembly to the deformable part.

[0094] By adopting the technical scheme, in the case of overcharging of the battery cell, the gas generated by the electrode assembly can reach the deformable part through the first air hole and push the deformable part to move towards the electrode terminal, so that the deformable part and the electrode terminal are in contact with each other, thereby cutting off the charging and discharging circuit of the battery cell, and further improving the safety performance of the battery cell.

[0095] The embodiments of the present application also provide a battery including the battery cell of any one of the above embodiments.

[0096] The battery provided by the embodiments of the present application has the beneficial effect that the battery provided by the embodiments of the present application effectively improves the safety performance of the battery due to the adoption of the battery cell of any one of the above embodiments.

[0097] The embodiments of the present application also provide an energy storage device including the battery.

[0098] The energy storage device provided by the embodiments of the present application has the beneficial effect that the energy storage device provided by the embodiments of the present application effectively improves the safety performance of the energy storage device due to the adoption of the battery of any one of the above embodiments.

[0099] The embodiments of the present application also provide an electric equipment including the battery.

[0100] The electric equipment provided by the embodiments of the present application has the beneficial effect that the electric equipment provided by the embodiments of the present application effectively improves the safety performance of the electric equipment due to the adoption of the battery of any one of the above embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0101] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or exemplary technical descriptions will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0102] FIG. 1 is a structural schematic diagram of a vehicle provided by the embodiments of the present application;

[0103] FIG. 2 is a structural schematic diagram of an energy storage device provided by the embodiments of the present application;

[0104] FIG. 3 is an explosion schematic diagram of a battery according to an embodiment of the present application;

[0105] FIG. 4 is a structural schematic diagram of a battery monomer according to an embodiment of the present application;

[0106] FIG. 5 is a top view schematic diagram of the battery monomer shown in FIG. 4;

[0107] FIG. 6 is a cross-sectional structural schematic diagram of the battery monomer shown in FIG. 5 along the direction of line A-A;

[0108] FIG. 7 is a structural schematic diagram of a first wall in the battery monomer shown in FIG. 6;

[0109] FIG. 8 is a structural schematic diagram of a first connecting piece in the battery monomer shown in FIG. 6;

[0110] FIG. 9 is a cross-sectional structural schematic diagram of the first connecting piece shown in FIG. 8 along the direction of line D-D;

[0111] FIG. 10 is a structural schematic diagram of a conductive piece in the battery monomer shown in FIG. 6;

[0112] FIG. 11 is a cross-sectional structural schematic diagram of the conductive piece shown in FIG. 10 along the direction of line E-E;

[0113] FIG. 12 is a structural schematic diagram of a first insulating piece in the battery monomer shown in FIG. 6;

[0114] FIG. 13 is a cross-sectional structural schematic diagram of the first insulating piece shown in FIG. 12 along the direction of line F-F;

[0115] FIG. 14 is a structural schematic diagram of a third connecting piece in the battery monomer shown in FIG. 6;

[0116] FIG. 15 is a cross-sectional structural schematic diagram of the third connecting piece shown in FIG. 14 along the direction of line G-G;

[0117] FIG. 16 is an enlarged structural schematic diagram of position B of the battery monomer shown in FIG. 6;

[0118] FIG. 17 is an enlarged structural schematic diagram of position H of the battery monomer shown in FIG. 16;

[0119] FIG. 18 is an enlarged structural schematic diagram of position C of the battery monomer shown in FIG. 6;

[0120] FIG. 19 is an explosion structural schematic diagram of a first wall, a deformable piece and a second insulating piece in the battery monomer shown in FIG. 4.

[0121] Legend of reference signs:

[0122] 1000, vehicle;

[0123] 2000, energy storage device;

[0124] 100, battery;

[0125] 10, box; 11, first part; 12, second part;

[0126] 20, battery cell;

[0127] 21, shell; 211, first wall body; 2111, connecting hole; 2112, electrode lead-out hole; 2113, pressure relief hole; 2114, first sealing surface; 2115, third sealing surface; 212, cover body; 213, housing; 2131, second wall body; 2132, third wall body;

[0128] 22, electrode assembly;

[0129] 23, electrode terminal; 231, terminal main body; 2311, conductive piece; 23111, second limiting groove; 23112, first boss; 2312, first insulating piece; 23121, first limiting groove; 23122, first insulating main body; 23123, second limiting part; 23124, insulating boss; 23125, communication groove; 232, second connecting piece; 2321, third clamping part; 2322, fourth clamping part; 2323, third connecting part; 2324, second clamping gap;

[0130] 24, first connecting piece; 241, first clamping part; 242, second clamping part; 243, first connecting part; 244, first limiting part; 245, first via hole; 246, second sealing surface; 247, first clamping gap; 248, third limiting groove;

[0131] 25, deformable piece; 251, second connecting part; 252, deformation part; 2521, second boss;

[0132] 26, third connecting piece; 261, fifth clamping part; 262, sixth clamping part; 263, fourth connecting part; 264, second via hole; 265, fourth limiting groove; 266, fourth sealing surface; 267, third clamping gap;

[0133] 27a, pressure relief mechanism; 27b, protective sheet;

[0134] 28, second insulating piece; 281, second insulating main body; 282, first blocking part; 2821, first air hole; 283, second blocking part; 2831, second air hole;

[0135] 29a, first sealing piece; 29b, second sealing piece; 29c, third sealing piece;

[0136] 400, battery cabin. DETAILED DESCRIPTION

[0137] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application and not intended to limit the present application.

[0138] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it can be directly on the other component or indirectly on the other component. When a component is referred to as being "connected to" another component, it can be directly or indirectly connected to the other component. The terms "upper", "lower", "left", "right", and the like indicate the orientation or positional relationship shown in the drawings based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. For those skilled in the art, the specific meanings of the above terms can be understood according to the specific circumstances. The terms "first", "second" are only for the purpose of convenient description, and cannot be understood as indicating or implying relative importance or implying the number of technical features.

[0139] In the embodiments of the present application, the same reference signs represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings are only exemplary and should not constitute any limitation on the present application.

[0140] The battery cell, as the smallest unit constituting the battery, generally includes a housing, an electrode assembly, and an electrode terminal. The electrode assembly is disposed in the housing, and the electrode terminal is disposed on the wall of the housing. The electrode terminal is connected to the electrode assembly to input or output the electric energy of the battery cell.

[0141] In actual use, the battery cell is prone to overcharging, which may cause thermal runaway in severe cases. Therefore, a deformable member needs to be provided on the battery cell. The deformable member is generally sealingly connected to the housing to isolate the internal environment of the housing from the external environment of the housing. In the case of overcharging of the battery cell, the electrode assembly will generate a large amount of gas. As the amount of gas increases, the internal pressure of the battery cell also increases. When the internal pressure of the battery cell reaches a threshold value, the deformation portion of the deformable member will act in the direction of the electrode terminal under the action of the pressure until the deformable member contacts the electrode terminal, so that the electrode terminal is electrically connected to the housing, thereby cutting off the charging and discharging circuit of the battery cell to reduce the risk of further deterioration of the overcharging of the battery cell.

[0142] In the related art, in order to improve the volume energy density of the battery monomer, the shell of the battery monomer is made of steel, and in order to enable the deformable member to act in the direction of the electrode terminal when the internal pressure of the battery monomer reaches a threshold value, the deformable member is usually made of aluminum. Since the material of the deformable member is different from that of the shell, the material properties of the deformable member are also different from those of the shell. After the deformable member is connected with the shell, a gap is easily generated at the connection between the deformable member and the shell, so that the deformable member cannot generate sufficient internal and external pressure difference in time, and the deformable member cannot deform in time and contact the electrode terminal, that is, the charging and discharging circuit of the battery monomer cannot be cut off in time, which further deteriorates the overcharge phenomenon of the battery monomer, and even causes thermal runaway, which is not conducive to improving the safety performance of the battery monomer.

[0143] In order to improve the safety performance of the battery monomer, the first connecting member in the battery monomer provided by the embodiments of the present application is connected with the first wall body, and the deformable member is connected with the first connecting member. Since the material of the deformable member is the same as that of the first connecting member, the material properties of the deformable member are also the same as those of the first connecting member. The difference in material state change of the deformable member and the first connecting member under the influence of environmental factors such as temperature and air pressure is effectively reduced, thereby effectively improving the connection reliability of the deformable member and the first connecting member, reducing the risk of generating a gap at the connection between the deformable member and the first connecting member, improving the situation that the gas generated by the electrode assembly leaks outward from the connection between the deformable member and the first connecting member, effectively improving the working reliability of the deformable member, and further effectively improving the safety performance of the battery monomer.

[0144] The battery monomer, the battery, the energy storage device using the battery as a power supply, and the power consumption device disclosed by the embodiments of the present application, wherein the energy storage device can be applied in small and medium-sized industrial and commercial energy storage scenes, large industrial and commercial energy storage scenes, light storage charging stations, and small and medium-sized micro-grid energy storage scenes, wind and light energy storage power stations, power grid energy storage power stations, and large micro-grid power station scenes, for storing and releasing electric energy. The power consumption device can be, but is not limited to, a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, and an electric tool.

[0145] Please refer to FIG. 2, which is a structural schematic diagram of an energy storage device 2000 provided by the embodiments of the present application. The energy storage device 2000 is a device for storing electric energy, and can be, but is not limited to, an energy storage container or an energy storage cabinet. The energy storage device 2000 can include a battery cabin 400 and a battery 100 arranged in the battery cabin 400, and can further include an electric control module for controlling the charging and discharging of the battery 100 and monitoring the working state of the battery 100, etc. For example, the electric control module is used to monitor the temperature, voltage, current, etc. of the battery 100.

[0146] Please refer to FIG. 3, which is an exploded schematic view of the battery 100 according to an embodiment of the present application. The battery 100 includes a box 10 and a battery cell 20, and the battery cell 20 is accommodated in the box 10. The box 10 is configured to provide a space for accommodating the battery cell 20, and the box 10 can have various structures. In some embodiments, the box 10 can include a first part 11 and a second part 12, and the first part 11 and the second part 12 are coupled to each other to define a space for accommodating the battery cell 20. The second part 12 can be a hollow structure with one open end, and the first part 11 can be a plate structure. The first part 11 is arranged on the open end of the second part 12 to define the space for accommodating the battery cell 20 together with the second part 12. Alternatively, the first part 11 and the second part 12 can both be hollow structures with one open end, and the open end of the first part 11 is arranged on the open end of the second part 12. Of course, the box 10 formed by the first part 11 and the second part 12 can have various shapes, such as a cylinder or a cuboid.

[0147] In some embodiments, the box 10 can be a part of the chassis structure of the vehicle 1000. For example, the box 10 can be at least a part of the floor of the vehicle 1000, or the box 10 can be at least a part of the cross beam and the longitudinal beam of the vehicle 1000.

[0148] 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 manner. The mixed manner 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 manner, and the whole of the multiple battery cells 20 is accommodated in the box 10. Of course, the battery 100 can also be that the multiple battery cells 20 are connected in series, in parallel, or in a mixed manner to form a battery module, and the multiple battery modules are connected in series, in parallel, or in a mixed manner to form a whole, and the whole is accommodated in the box 10. The battery 100 can further include other functional components. For example, the battery 100 can further include a busbar for electrically connecting the multiple battery cells 20.

[0149] Each battery cell 20 can be a secondary battery cell or a primary battery cell, where the secondary battery cell refers to a battery cell 20 that can be activated by charging after the battery cell 20 is discharged, and the primary battery cell refers to a battery cell 20 that cannot be activated by charging after the battery cell 20 is discharged; the battery cell 20 can also be a lithium ion battery cell, a sodium ion battery cell, a sodium lithium ion battery cell, a lithium metal battery cell, a sodium metal battery cell, a lithium sulfur battery cell, a magnesium ion battery cell, a nickel-hydrogen battery cell, a nickel-cadmium battery cell, a lead-acid battery cell, or the like, but is not limited thereto. The battery cell 20 can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell 20 of another shape, and the prismatic battery cell includes a square battery cell, a blade battery cell, a multi-prismatic battery cell, such as a hexagonal battery cell, and the like, without particular limitation.

[0150] Of course, in some embodiments, the battery 100 can not include the case 10, and a plurality of battery cells 20 are electrically connected and assembled into the energy storage device 2000 or the electrical device by forming a whole through necessary fixing structures.

[0151] To illustrate the technical solutions provided in the present application, the following will be described in detail in combination with specific drawings and embodiments.

[0152] In a first aspect, in combination with FIGS. 4, 5, 6, and 16, the embodiments of the present application provide a battery cell 20, which includes an electrode assembly 22, a housing 21, an electrode terminal 23, a first connecting piece 24, and a deformable piece 25. The housing 21 is configured to accommodate the electrode assembly 22, and the housing 21 includes a first wall body 211. The electrode terminal 23 is configured to electrically connect the electrode assembly 22, and the electrode terminal 23 is disposed on the first wall body 211. The first connecting piece 24 is connected to the first wall body 211, and the material of the first connecting piece 24 is different from that of the first wall body 211. The deformable piece 25 is connected to the first connecting piece 24, and the material of the deformable piece 25 is the same as that of the first connecting piece 24. The deformable piece 25 is configured to be deformable to contact the electrode terminal 23, so as to electrically connect the first wall body 211 and the electrode terminal 23.

[0153] The electrode assembly 22 is a component in which electrochemical reactions occur in the battery cell 20. The battery cell 20 can include one or more electrode assemblies 22. The main body portion of the electrode assembly 22 is manufactured by a jelly-roll process or a stacking process using a positive electrode sheet, a negative electrode sheet, and a separator. The positive electrode sheet and the negative electrode sheet can be provided in plural, and the plural positive electrode sheets and the plural negative electrode sheets can be alternately stacked. The separator can be provided between the adjacent positive electrode sheets and the negative electrode sheets to insulate and separate the positive electrode sheets and the negative electrode sheets. The shape of the electrode assembly 22 can be, but is not limited to, a cylindrical shape, a flat shape, and a polygonal prism shape. In some embodiments, the electrode assembly 22 can further include tabs including a positive tab and a negative tab, the positive tab being connected to the positive electrode sheet, and the negative tab being connected to the negative electrode sheet, to lead out or input current from or to the electrode assembly 22.

[0154] In some embodiments, the positive electrode sheet can be provided in plural, and the negative electrode sheet can be folded to form plural folded segments which are stacked. One positive electrode sheet can be interposed between the adjacent folded segments.

[0155] In other embodiments, the negative electrode sheet can be provided in plural, and the positive electrode sheet can be folded to form plural folded segments which are stacked. One negative electrode sheet can be interposed between the adjacent folded segments.

[0156] In still other embodiments, the positive electrode sheet and the negative electrode sheet can be folded to form plural folded segments which are stacked. The plural folded segments of the positive electrode sheet and the plural folded segments of the negative electrode sheet can be alternately stacked.

[0157] In some embodiments, the separator can be provided in plural, and can be provided between any adjacent positive electrode sheets or negative electrode sheets.

[0158] In other embodiments, the separator can be continuously provided, and can be provided between any adjacent positive electrode sheets or negative electrode sheets by being folded or wound.

[0159] In some embodiments, the battery cell 20 can further include an electrolyte which functions to conduct ions between the positive electrode sheet and the negative electrode sheet. The electrolyte can be, but is not limited to, a liquid electrolyte, a gel electrolyte, and a solid electrolyte.

[0160] The case 21 is a component for providing an internal environment of the battery cell 20, which can be used to accommodate the electrode assembly 22, the deformable member 25, the electrolyte, and other functional components.

[0161] In some embodiments, the shell 21 can include a housing 213 and a cover 212, wherein the housing 213 has a cavity, an opening can be provided on the housing 213, the cavity is communicated with the external environment of the battery monomer 20 through the opening, and the cavity of the housing 213 is isolated from the external environment of the battery monomer 20 by covering the opening with the cover 212 to form the internal environment of the battery monomer 20. Specifically, the housing 213 and the cover 212 can form a common connecting surface before other components enter the shell, and when it is necessary to encapsulate the inside of the housing 213, the cover 212 is covered on the opening of the housing 213. The shape of the housing 213 can be determined according to the specific shape and size of the electrode assembly 22, and the shape of the housing 213 can be but not limited to a cuboid, a cylinder, a hexagonal prism, etc. The shape of the cover 212 can be adapted to the shape of the opening of the housing 213, and the shape of the cover 212 can be but not limited to a cuboid, a cylinder, a hexagonal prism, etc.

[0162] The first wall 211 can be any wall of the shell 21, for example, the first wall 211 can be the cover 212, and for another example, the first wall 211 can be the bottom wall of the housing 213, that is, the wall of the housing 213 opposite to the opening. In some embodiments, the cover 212 constitutes the first wall 211, the housing 213 includes a second wall 2131 and a third wall 2132, the third wall 2132 is arranged around the second wall 2131 and connected with the periphery of the second wall 2131 to define the cavity, the first wall 211 is covered on the opening of the housing 213, and the first wall 211 is arranged opposite to the second wall 2131.

[0163] The first connecting piece 24 is a component for connecting the first wall 211 and the deformable piece 25. The connection mode of the first connecting piece 24 and the first wall 211 can be but not limited to riveting, threaded connection, etc., and the connection mode of the first connecting piece 24 and the deformable piece 25 can be but not limited to welding, press-fit connection, etc.

[0164] The material of the first connecting piece 24 is different from that of the first wall 211, that is, the first connecting piece 24 and the first wall 211 are made of different materials, for example, the first connecting piece 24 is made of aluminum alloy, and the first wall 211 is made of steel, and for another example, the first connecting piece 24 is made of steel, and the first wall 211 is made of aluminum alloy.

[0165] The deformable member 25 is a component for short-circuiting the positive electrode and the negative electrode of the battery cell 20 in the case where overcharge occurs in the battery cell 20. The deformable member 25 is connected to the first connecting member 24, and the connection manner of the deformable member 25 to the first connecting member 24 can be, but is not limited to, welding, press-fit connection, etc. In the case where overcharge occurs in the battery cell 20, the electrode assembly 22 generates more gas, and as the gas increases, the internal pressure of the battery cell 20 increases. When the internal pressure of the battery cell 20 reaches a threshold value, the pressure acts on the side of the deformable member 25 facing the electrode assembly 22, so that at least part of the deformable member 25 moves toward the electrode terminal 23 until the deformable member 25 contacts the electrode terminal 23, so as to electrically connect the electrode terminal 23 and the housing 21, thereby cutting off the charge-discharge circuit of the battery cell 20.

[0166] The same material of the deformable member 25 as that of the first connecting member 24 means that the deformable member 25 and the first connecting member 24 are made of the same material, for example, the deformable member 25 and the first connecting member 24 are both made of aluminum alloy, or for example, the deformable member 25 and the first connecting member 24 are both made of steel.

[0167] The electrode terminal 23 is a component electrically connected to the electrode assembly 22 for outputting the electric energy of the battery cell 20 or inputting the electric energy to the battery cell 20. The electrode terminal 23 is arranged on the first wall body 211, part of the electrode terminal 23 extends into the internal environment of the battery cell 20 and is directly or indirectly connected to the tab of the electrode assembly 22, and the other part of the electrode terminal 23 is exposed to the external environment of the battery cell 20 and is connected to the bus member, the sampling device, etc.

[0168] In some embodiments, in order to improve the overcurrent capacity of the electrode terminal 23, the projection shape of the electrode terminal 23 along the thickness direction of the first wall body 211 is substantially square, so as to increase the overcurrent area of the electrode terminal 23, thereby improving the overcurrent capacity of the electrode terminal 23.

[0169] Of course, in other embodiments, the projection shape of the electrode terminal 23 along the thickness direction of the first wall body 211 can also be other shape structures, for example, circular, etc.

[0170] It can be understood that the first wall body 211, the first connecting member 24 and the deformable member 25 are all made of conductive material, and in the case where the internal pressure of the battery cell 20 reaches a threshold value, the deformable member 25 moves toward the direction close to the electrode terminal 23 and contacts the conductive part of the electrode terminal 23, so as to electrically connect the first wall body 211, the first connecting member 24, the deformable member 25 and the electrode terminal 23.

[0171] The first connecting piece 24 in the battery monomer 20 provided by the embodiments of the present application is connected with the first wall body 211, and the deformable piece 25 is connected with the first connecting piece 24. Since the material of the deformable piece 25 is the same as that of the first connecting piece 24, the material characteristics of the deformable piece 25 are also the same as those of the first connecting piece 24. The material state change difference of the deformable piece 25 and the first connecting piece 24 under the influence of environmental factors such as temperature and air pressure is effectively reduced, the connection reliability of the deformable piece 25 and the first connecting piece 24 is effectively improved, the risk of a gap occurring at the connection between the deformable piece 25 and the first connecting piece 24 is reduced, the situation of gas generated by the electrode assembly 22 leaking outward from the connection between the deformable piece 25 and the first connecting piece 24 is improved, the working reliability of the deformable piece 25 is effectively improved, and the safety performance of the battery monomer 20 is effectively improved.

[0172] In some embodiments of the present application, referring to FIGS. 8, 9, 16 and 17, the first connecting piece 24 includes a first clamping portion 241, a second clamping portion 242 and a first connecting portion 243, the first connecting portion 243 is connected between the first clamping portion 241 and the second clamping portion 242, and the first clamping portion 241 and the second clamping portion 242 cooperate to clamp the first wall body 211.

[0173] The first clamping portion 241 and the second clamping portion 242 are arranged opposite along the thickness direction of the first wall body 211, the first clamping portion 241, the second clamping portion 242 and the first connecting portion 243 define a first clamping gap 247, at least part of the first wall body 211 is inserted into the first clamping gap 247, the first clamping portion 241 is pressed against one side of the first wall body 211 along the thickness direction, and the second clamping portion 242 is pressed against the other side of the first wall body 211 along the thickness direction, so that the first clamping portion 241 and the second clamping portion 242 cooperate to clamp and fix the first wall body 211, thereby realizing the fixed connection between the first connecting piece 24 and the first wall body 211.

[0174] In some embodiments, the first connecting piece 24 can be an integrally formed member, for example, the first connecting piece 24 is integrally formed by a stamping process. In other embodiments, the first clamping portion 241, the second clamping portion 242 and the first connecting portion 243 can be respectively formed and then connected into an integral whole, for example, the first clamping portion 241, the second clamping portion 242 and the first connecting portion 243 are welded into an integral whole.

[0175] As an example, the deformable piece 25 can be connected with the first connecting portion 243.

[0176] As an example, the deformable piece 25 can be connected with the first clamping portion 241.

[0177] As an example, the deformable piece 25 can be connected with the second clamping portion 242.

[0178] By adopting the above technical solutions, the connection reliability of the first wall body 211 and the first connecting piece 24 is effectively improved, the connection tightness of the first wall body 211 and the first connecting piece 24 is increased, the risk of a gap occurring at the connection of the first wall body 211 and the first connecting piece 24 is reduced, the situation of gas generated by the electrode assembly 22 leaking outward from the connection of the first wall body 211 and the first connecting piece 24 is improved, the working reliability of the deformable piece 25 is further improved, and the safety performance of the battery monomer 20 is further improved.

[0179] In some embodiments of the present application, referring to FIGS. 7-9 and 16, the first wall body 211 is provided with a connecting hole 2111 penetrating through the first wall body 211 along the thickness direction of the opposite two sides, and the first clamping portion 241 and the second clamping portion 242 cooperate to clamp the hole rim of the connecting hole 2111.

[0180] In some embodiments, the first clamping portion 241 and the second clamping portion 242 extend along the hole rim of the connecting hole 2111 and close to form a ring structure, so that the first clamping portion 241 and the second clamping portion 242 cooperate to clamp the entire hole rim of the connecting hole 2111. The outer peripheral contour shape of the first clamping portion 241 and the outer peripheral contour shape of the second clamping portion 242 can be matched with the shape of the connecting hole 2111, for example, the connecting hole 2111 is a circular hole, and the first clamping portion 241 and the second clamping portion 242 are both circular ring structures.

[0181] By adopting the above technical solutions, the first wall body 211 and the first connecting piece 24 are conveniently connected, and the connection reliability of the first wall body 211 and the first connecting piece 24 is effectively improved.

[0182] In some embodiments of the present application, referring to FIGS. 8, 9 and 16, the first connecting piece 24 is provided with a first via hole 245 penetrating through the first connecting piece 24 along the thickness direction of the opposite two sides of the first wall body 211, and the deformable piece 25 is configured to be deformable to contact the electrode terminal 23 through the first via hole 245.

[0183] In some embodiments, the first connecting portion 243 is in a ring structure, the inner ring space of the first connecting portion 243 constitutes the above-mentioned first via hole 245, and the first clamping portion 241 and the second clamping portion 242 are protruded on the outer peripheral side of the first connecting portion 243 and arranged around the first via hole 245. As an example, the deformable piece 25 can be connected to one side of the first connecting portion 243 facing the electrode assembly 22, and the part of the electrode terminal 23 directly opposite the deformable piece 25 protrudes in the direction of approaching the deformable piece 25 along the thickness direction of the first wall body 211 to form a first boss 23112, and at least part of the first boss 23112 extends into the first via hole 245 and is used to contact the deformable piece 25.

[0184] Of course, in other embodiments, the deformable member 25 can also be connected to other parts of the first connecting part 243, for example, the deformable member 25 is connected to the side of the first connecting part 243 away from the electrode assembly 22, or the deformable member 25 is connected to the inner ring wall of the first connecting part 243.

[0185] By adopting the above technical solution, the deformable member 25 and the electrode terminal 23 are facilitated to be in contact in the case that the internal pressure of the battery monomer 20 reaches a threshold value.

[0186] In some embodiments of the present application, referring to FIG. 16, the deformable member 25 includes a second connecting part 251 connected with the first connecting part 24 and a deformation part 252 configured to be deformable to contact the electrode terminal 23 through the first via hole 245.

[0187] The second connecting part 251 is a part for connecting the first connecting part 24, and the deformation part 252 is a part for contacting the electrode terminal 23. The second connecting part 251 is connected with the first connecting part 24 to form a sealing boundary. In the case that the battery monomer 20 is overcharged, the electrode assembly 22 will generate more gas, and as the gas increases, the internal pressure of the battery monomer 20 will also increase. In the case that the internal pressure of the battery monomer 20 reaches a threshold value, the pressure acts on the side of the deformation part 252 facing the electrode assembly 22, so that at least part of the deformation part 252 moves in the direction of the electrode terminal 23 until the deformation part 252 contacts the electrode terminal 23, so that the electrode terminal 23 is electrically connected with the shell 21, thereby cutting off the charging and discharging circuit of the battery monomer 20.

[0188] As an example, the second connecting part 251 and the deformation part 252 can be an integrally formed member, for example, the deformable member 25 is integrally formed by a stamping process. The second connecting part 251 and the deformation part 252 can also be formed separately and then connected to form a whole, for example, the second connecting part 251 and the deformation part 252 are welded to each other after being formed separately.

[0189] By adopting the above technical solution, not only the deformable member 25 and the first connecting part 24 are facilitated to be connected, but also the deformable member 25 and the electrode terminal 23 are facilitated to be in contact in the case that the internal pressure of the battery monomer 20 reaches a threshold value.

[0190] In some embodiments of the present application, referring to FIG. 16, the second connecting part 251 is arranged around the deformation part 252 and the first via hole 245.

[0191] In some embodiments, the first connecting portion 243 and the second connecting portion 251 are both annular structures, the inner annular space of the first connecting portion 243 constitutes the first through hole 245, the first clamping portion 241 and the second clamping portion 242 are protruded on the outer circumferential side of the first connecting portion 243 and arranged around the first through hole 245, the first clamping portion 241 and the second clamping portion 242 cooperate to clamp the hole rim of the connecting hole 2111, the deformation portion 252 is connected to the inner circumferential wall of the second connecting portion 251 to close the inner annular space of the second connecting portion 251, and the second connecting portion 251 is connected to the side of the first connecting portion 243 facing or away from the electrode assembly 22 to form an annular sealing boundary, which is arranged around the first through hole 245 to close the first through hole 245.

[0192] Of course, in other embodiments, the second connecting portion 251 can also be connected to the inner circumferential wall of the first connecting portion 243 to close the first through hole 245.

[0193] By adopting the above technical solution, the second connecting portion 251 can be connected with the first connecting member 24 along the circumferential direction of the second connecting portion 251, so that a sealing boundary around the first through hole 245 is formed between the deformable member 25 and the first connecting member 24, which not only effectively closes the first through hole 245, but also further improves the connection reliability of the deformable member 25 and the first connecting member 24.

[0194] In some embodiments of the present application, referring to FIG. 16, the distance L1 between the deformation portion 252 and the electrode terminal 23 along the thickness direction of the first wall body 211 is 0.2-1.5 mm.

[0195] It should be noted that the distance L1 between the deformation portion 252 and the electrode terminal 23 along the thickness direction of the first wall body 211 refers to the minimum distance between the part of the deformation portion 252 used to contact the electrode terminal 23 and the part of the electrode terminal 23 used to contact the deformation portion 252 along the thickness direction of the first wall body 211 when the deformable member 25 is not in action. The distance L1 between the deformation portion 252 and the electrode terminal 23 along the thickness direction of the first wall body 211 can be selected and set within the above range according to actual application needs, and can be specifically 0.2 mm, 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, etc.

[0196] By adopting the above technical solutions, not only can the deformable member 25 and the electrode terminal 23 have sufficient insulation spacing, thereby reducing the risk of the battery monomer 20 being short-circuited due to the deformable member 25 and the electrode terminal 23 being in contact under the condition that the battery monomer 20 is in a normal working state, but also can the action stroke of the deformable member 25 not be too large, so that the deformable member 25 can timely contact the electrode terminal 23 under the condition that the internal pressure of the battery monomer 20 reaches the threshold value, thereby effectively improving the safety performance of the battery monomer 20.

[0197] In some embodiments of the present application, the contact area of the deformable member 25 and the electrode terminal 23 is 20mm 2 -500mm 2 .

[0198] It should be noted that the contact area of the deformable member 25 and the electrode terminal 23 under the condition that the internal pressure of the battery monomer 20 reaches the threshold value refers to the area of the contact interface formed by the deformable member 25 and the electrode terminal 23 under the condition that the internal pressure of the battery monomer 20 reaches the threshold value. The contact area of the deformable member 25 and the electrode terminal 23 under the condition that the internal pressure of the battery monomer 20 reaches the threshold value can be selected and set within the above range according to actual application needs, and can be 20mm 2 , 30mm 2 , 40mm 2 , 50mm 2 , 60mm 2 , 70mm 2 , 80mm 2 , 90mm 2 , 100mm 2 , 150mm 2 , 200mm 2 , 250mm 2 , 300mm 2 , 350mm 2 , 400mm 2 , 450mm 2 , 500mm 2 , etc.

[0199] In some embodiments, the electrode terminal 23 protrudes in the thickness direction of the first wall body 211 towards the deformable member 25 at a position opposite to the deformable member 25 to form a first protrusion 23112, the deformable member 25 includes a second connecting portion 251 for connecting the first connecting member 24 and a deformed portion 252 connected to the second connecting portion 251, a middle portion of the deformed portion 252 is arranged opposite to the first protrusion 23112 and protrudes in the thickness direction of the first wall body 211 towards the first protrusion 23112 to form a second protrusion 2521, and in the case that the internal pressure of the battery monomer 20 reaches the threshold value, the end surface of the first protrusion 23112 facing the second protrusion 2521 abuts against the end surface of the second protrusion 2521 facing the first protrusion 23112 to form the contact interface.

[0200] For example, the first protrusion 23112 and the second protrusion 2521 are both in a cylindrical structure, and in the case that the internal pressure of the battery monomer 20 reaches the threshold value, the end surface of the first protrusion 23112 facing the second protrusion 2521 is in contact with the second protrusion 2521, and the area of the end surface of the first protrusion 23112 facing the second protrusion 2521 is 20mm 2 -500mm 2 .

[0201] For example, the first protrusion 23112 and the second protrusion 2521 are both in a cylindrical structure, and in the case that the internal pressure of the battery monomer 20 reaches the threshold value, the end surface of the second protrusion 2521 facing the first protrusion 23112 is in contact with the first protrusion 23112, and the area of the end surface of the second protrusion 2521 facing the first protrusion 23112 is 20mm 2 -500mm 2 .

[0202] By adopting the above technical solutions, not only can the deformable member 25 and the electrode terminal 23 have sufficient flow area to enable the short-circuit current to flow through the fuse device to melt the fuse device, thereby cutting off the charging and discharging circuit of the battery monomer 20, but also the contact area of the deformable member 25 and the electrode terminal 23 can be limited to reduce the space occupied by the protection structure composed of the deformable member 25 and the electrode terminal 23, thereby optimizing the volume energy density of the battery monomer 20.

[0203] In some embodiments of the present application, referring to FIG. 16, the battery monomer 20 further includes a first sealing member 29a arranged between the first wall body 211 and the first connecting member 24 to seal the connection between the first wall body 211 and the first connecting member 24.

[0204] The first sealing member 29a is a component for sealing the gap between the first wall body 211 and the first connecting member 24. The first sealing member 29a can be made of a flexible material, which can be but is not limited to rubber, silicone, etc.

[0205] In some embodiments, the first wall body 211 is provided with a connecting hole 2111, and the first connecting member 24 includes a first clamping portion 241, a second clamping portion 242, and a first connecting portion 243 connected between the first clamping portion 241 and the second clamping portion 242, and the first clamping portion 241 and the second clamping portion 242 are arranged to clamp the hole rim of the connecting hole 2111. As an example, the first sealing member 29a is arranged between the first clamping portion 241 and the hole rim of the connecting hole 2111. As an example, the first sealing member 29a is arranged between the second clamping portion 242 and the hole rim of the connecting hole 2111. As an example, the first sealing member 29a is arranged between the first connecting portion 243 and the hole rim of the connecting hole 2111. As an example, a part of the first sealing member 29a is arranged between the first clamping portion 241 and the hole rim of the connecting hole 2111, another part of the first sealing member 29a is arranged between the second clamping portion 242 and the hole rim of the connecting hole 2111, and still another part of the first sealing member 29a is arranged between the first clamping portion 241 and the hole rim of the connecting hole 2111.

[0206] In some embodiments, the first connecting portion 243 has a ring structure, the inner ring space of the first connecting portion 243 forms a first through hole 245, the first clamping portion 241 and the second clamping portion 242 are arranged on the outer circumferential side of the first connecting portion 243 and surround the first through hole 245, and the first sealing member 29a has a ring structure and is arranged to surround the first through hole 245.

[0207] By adopting the above technical solutions, the sealing effect of the connection between the first wall body 211 and the first connecting member 24 is effectively improved, the leakage of the gas generated by the electrode assembly 22 from the connection between the first wall body 211 and the first connecting member 24 is improved, the working reliability of the deformable member 25 is further improved, and the safety performance of the battery monomer 20 is further improved.

[0208] In some embodiments of the present application, referring to FIG. 17, the first wall body 211 has a first sealing surface 2114, the first connecting member 24 has a second sealing surface 246, the first sealing surface 2114 and the second sealing surface 246 clamp the first sealing member 29a, and the compression rate of the first sealing member 29a in the direction from the first sealing surface 2114 to the second sealing surface 246 is 2%-50%.

[0209] In some embodiments, the first seal 29a is arranged between the first clamping portion 241 and the hole edge of the connecting hole 2111, the surface of the hole edge of the connecting hole 2111 facing the first clamping portion 241 constitutes the first sealing surface 2114, and the surface of the first clamping portion 241 facing the hole edge of the connecting hole 2111 constitutes the second sealing surface 246.

[0210] In other embodiments, the first seal 29a is arranged between the second clamping portion 242 and the hole edge of the connecting hole 2111, the surface of the hole edge of the connecting hole 2111 facing the second clamping portion 242 constitutes the first sealing surface 2114, and the surface of the second clamping portion 242 facing the hole edge of the connecting hole 2111 constitutes the second sealing surface 246.

[0211] In yet other embodiments, the first seal 29a is arranged between the first connecting portion 243 and the hole edge of the connecting hole 2111, the surface of the hole edge of the connecting hole 2111 facing the first connecting portion 243 constitutes the first sealing surface 2114, and the surface of the first connecting portion 243 facing the hole edge of the connecting hole 2111 constitutes the second sealing surface 246.

[0212] The compression rate of the first seal 29a refers to the ratio of the size L2 of the first seal 29a after compression to the original size of the first seal 29a. It should be noted that the size L2 of the first seal 29a after compression refers to the size of the first seal 29a in the direction from the first sealing surface 2114 to the second sealing surface 246 after being extruded by the first wall body 211 and the first connecting member 24, and the original size of the first seal 29a refers to the size of the first seal 29a in the direction from the first sealing surface 2114 to the second sealing surface 246 before being assembled between the first wall body 211 and the first connecting member 24.

[0213] By adopting the above technical solutions, not only the sealing effect of the connecting part of the first wall body 211 and the first connecting member 24 is effectively improved, but also the risk of rupture of the first seal 29a due to excessive pressure is reduced, and the reliability of the first seal 29a is effectively improved.

[0214] In some embodiments of the present application, referring to FIGS. 16 and 17, the electrode terminal 23 includes a terminal body 231, and a first limiting structure is arranged between the terminal body 231 and the first connecting member 24, the first limiting structure being used to limit the relative position of the terminal body 231 and the first connecting member 24 in a preset direction, and the preset direction is not parallel to the thickness direction of the first wall body 211.

[0215] The terminal body 231 is a main body part of the electrode terminal 23, and can be arranged on the side of the first wall body 211 away from the electrode assembly 22. In the case where the internal pressure of the battery cell 20 reaches a threshold value, the deformable member 25 can act in the direction close to the terminal body 231 and contact the conductive part of the terminal body 231 to electrically connect the electrode terminal 23 and the shell 21, thereby cutting off the charging and discharging circuit of the battery cell 20.

[0216] The first limiting structure is a structure for limiting the relative position of the terminal body 231 and the first connecting member 24 in the above-mentioned preset direction, which can be but is not limited to a concave-convex matching structure, a bolt structure, etc. The above-mentioned preset direction is not parallel to the thickness direction of the first wall body 211. As an example, the above-mentioned preset direction can be any direction perpendicular to the thickness direction of the first wall body 211, for example, the above-mentioned preset direction can be the width direction of the first wall body 211, and for another example, the above-mentioned preset direction can be the length direction of the first wall body 211.

[0217] By adopting the above technical solution, the relative position of the terminal body 231 and the first connecting member 24 in the above-mentioned preset direction is effectively limited, thereby effectively reducing the risk of displacement of the terminal body 231 in the preset direction.

[0218] In some embodiments of the present application, referring to FIGS. 16 and 17, the side of the terminal body 231 facing the electrode assembly 22 is recessed with a first limiting groove 23121, and the first connecting member 24 includes a first limiting part 244, at least part of the first limiting part 244 being arranged in the first limiting groove 23121 to form a first limiting structure.

[0219] In some embodiments, the first connecting piece 24 comprises a first clamping portion 241, a second clamping portion 242, and a first connecting portion 243 connected between the first clamping portion 241 and the second clamping portion 242, the first clamping portion 241 and the second clamping portion 242 being configured to clamp the first wall body 211, wherein the first clamping portion 241 is arranged on a side of the first wall body 211 facing the electrode assembly 22, the second clamping portion 242 is arranged on a side of the first wall body 211 away from the electrode assembly 22, and the second clamping portion 242 forms the first limiting portion 244. For example, the first wall body 211 is provided with a connecting hole 2111, the first clamping portion 241 and the second clamping portion 242 extend along a hole edge of the connecting hole 2111 and are closed to form a ring structure, so that the first clamping portion 241 and the second clamping portion 242 clamp the entire hole edge of the connecting hole 2111, the first connecting portion 243 is in a ring structure, an inner ring space of the first connecting portion 243 forms the first via hole 245, and the first clamping portion 241 and the second clamping portion 242 are arranged on an outer circumferential side of the first connecting portion 243 and surround the first via hole 245. The first limiting groove 23121 is a ring groove, and at least a portion of the second clamping portion 242 is arranged in the first limiting groove 23121.

[0220] It can be understood that, in order to facilitate the assembly of the first limiting portion 244 into the first limiting groove 23121, a dimension of the first limiting groove 23121 in a direction perpendicular to a thickness direction of the first wall body 211 is greater than or equal to a dimension of the first limiting portion 244 in the direction perpendicular to the thickness direction of the first wall body 211. For example, when the first limiting groove 23121 is a ring groove and the first limiting portion 244 is in a ring structure, a width of the first limiting groove 23121 is greater than or equal to a width of the first limiting portion 244, for example, the difference between the width of the first limiting groove 23121 and the width of the first limiting portion 244 is 0 mm-0.5 mm, and specifically can be 0 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, etc.

[0221] By using the above technical solution, the first limiting structure is effectively simplified, and the relative position of the terminal main body 231 and the first connecting piece 24 in the preset direction is facilitated to be limited.

[0222] In some embodiments of the present application, referring to FIG. 17, the first limiting portion 244 is arranged on a side of the first wall body 211 away from the electrode assembly 22, and a depth H1 of the first limiting groove 23121 is greater than or equal to a protruding height H2 of the first limiting portion 244 from the side of the first wall body 211 away from the electrode assembly 22.

[0223] The depth H1 of the first limiting groove 23121 refers to a dimension of the first limiting groove 23121 along a thickness direction of the first wall body 211, and the protruding height H2 of the first limiting portion 244 from the side of the first wall body 211 away from the electrode assembly 22 refers to a dimension of the first limiting portion 244 from the side of the first wall body 211 away from the electrode assembly 22 along the thickness direction of the first wall body 211. Since the depth H1 of the first limiting groove 23121 is greater than or equal to the protruding height H2 of the first limiting portion 244 from the side of the first wall body 211 away from the electrode assembly 22, in the thickness direction of the first wall body 211, the portion of the first limiting portion 244 protruding from the side of the first wall body 211 away from the electrode assembly 22 towards the terminal body 231 can be entirely accommodated in the first limiting groove 23121, so that the terminal body 231 can be attached to the side of the first wall body 211 away from the electrode assembly 22.

[0224] By adopting the above technical solution, the portion of the first limiting portion 244 protruding from the side of the first wall body 211 away from the electrode assembly 22 is accommodated in the first limiting groove 23121, effectively improving the situation that the terminal body 231 is lifted by the first limiting portion 244, so that the terminal body 231 and the first wall body 211 can be attached to each other, facilitating the assembly of the battery monomer 20.

[0225] In some embodiments of the present application, referring to FIG. 17, the difference between the depth H1 of the first limiting groove 23121 and the protruding height H2 of the first limiting portion 244 from the side of the first wall body 211 away from the electrode assembly 22 is 0mm-0.5mm.

[0226] The difference between the depth H1 of the first limiting groove 23121 and the protruding height H2 of the first limiting portion 244 from the side of the first wall body 211 away from the electrode assembly 22 can be selected and set within the above range according to actual application needs, and can be 0mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, etc.

[0227] By adopting the above technical solution, not only is the situation that the terminal body 231 is lifted by the first limiting portion 244 effectively improved, but also the depth of the first limiting groove 23121 can be optimized, so that the terminal body 231 has sufficient structural strength.

[0228] In some embodiments of the present application, referring to FIG. 16 and FIG. 17, the terminal body 231 includes a conductive piece 2311 and a first insulating piece 2312, the deformable piece 25 is configured to be deformable to contact the conductive piece 2311, the first insulating piece 2312 is arranged between the conductive piece 2311 and the first wall body 211, and the above first limiting structure is arranged between the first insulating piece 2312 and the first connecting piece 24.

[0229] The conductive member 2311 refers to a member made of a conductive material, and the conductive material can be, but is not limited to, copper, aluminum, steel, etc. The conductive member 2311 is used to contact the deformable member 25 when the internal pressure of the battery monomer 20 reaches a threshold value, and is also used to electrically connect components such as bus members, sampling devices, etc.

[0230] The first insulating member 2312 refers to a member made of an insulating material, and the insulating material can be, but is not limited to, polyester, epoxy, polyurethane, polybutadiene acid, silicone, polyester imine, and polyimide, etc. The first insulating member 2312 is located between the conductive member 2311 and the first wall body 211, and is used to insulate and separate the conductive member 2311 from the first wall body 211, and is also used to insulate and separate the conductive member 2311 from the first connecting member 24, thereby reducing the risk of short circuit.

[0231] The first limiting structure is arranged between the first insulating member 2312 and the first connecting member 24. In some embodiments, as shown in FIGS. 12, 13, 16 and 17, a side of the first insulating member 2312 facing the first wall body 211 is recessed with a first limiting groove 23121, and the first connecting member 24 includes a first limiting portion 244, at least part of the first limiting portion 244 is arranged in the first limiting groove 23121, so as to form the above-mentioned first limiting structure.

[0232] By adopting the above technical solution, it is convenient to arrange the first limiting structure on the terminal body 231.

[0233] In some embodiments of the present application, please refer to FIGS. 16 and 17, a second limiting structure is arranged between the conductive member 2311 and the first insulating member 2312, and the second limiting structure is used to limit the relative position of the conductive member 2311 and the first insulating member 2312 along the above-mentioned preset direction.

[0234] The second limiting structure is a structure used to limit the relative position of the conductive member 2311 and the first insulating member 2312 along the above-mentioned preset direction, and the second limiting structure can be, but is not limited to, a concave-convex matching structure, a bolt structure, etc.

[0235] By adopting the above technical solution, not only the relative position of the first connecting member 24 and the first insulating member 2312 along the above-mentioned preset direction is limited by the first limiting structure, but also the relative position of the first insulating member 2312 and the conductive member 2311 along the above-mentioned preset direction is limited by the second limiting structure, thereby further reducing the risk of displacement of the terminal body 231 along the above-mentioned preset direction.

[0236] In some embodiments of the present application, referring to FIGS. 10-13 and FIGS. 16-17, the side of the conductive member 2311 facing the first insulating member 2312 is concavely provided with a second limiting groove 23111, and the first insulating member 2312 includes a first insulating body 23122 and a second limiting portion 23123. The first insulating body 23122 is arranged between the conductive member 2311 and the first wall body 211, and at least part of the second limiting portion 23123 is arranged in the second limiting groove 23111 to form a second limiting structure.

[0237] The first insulating body 23122 is a main part of the first insulating member 2312, and is used to insulate and separate the conductive member 2311 from the first wall body 211 and to insulate and separate the conductive member 2311 from the first connecting member 24. The second limiting portion 23123 is protrudingly arranged on the side of the first insulating body 23122 away from the first wall body 211 and is used to cooperate with the second limiting groove 23111 to limit the relative position of the first insulating member 2312 and the conductive member 2311 along the above-mentioned predetermined direction.

[0238] In some embodiments, the second limiting groove 23111 is an annular groove, and the second limiting portion 23123 has an annular structure. At least part of the second limiting portion 23123 is arranged in the second limiting groove 23111.

[0239] It can be understood that, in order to facilitate the assembly of the second limiting portion 23123 into the second limiting groove 23111, the size of the second limiting groove 23111 along a direction perpendicular to the thickness direction of the first wall body 211 is greater than or equal to the size of the second limiting portion 23123 along the direction perpendicular to the thickness direction of the first wall body 211. For example, in the case where the second limiting groove 23111 is an annular groove and the second limiting portion 23123 has an annular structure, the width of the second limiting groove 23111 is greater than or equal to the width of the second limiting portion 23123. For example, the difference between the width of the second limiting groove 23111 and the width of the second limiting portion 23123 is 0 mm-0.5 mm, and specifically can be 0 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, etc.

[0240] By adopting the above technical solution, the second limiting structure is effectively simplified, and the relative position of the first insulating member 2312 and the conductive member 2311 along the above-mentioned predetermined direction is facilitated to be limited.

[0241] In some embodiments of the present application, referring to FIG. 17, the second limiting portion 23123 is protrudingly arranged on the side of the first insulating body 23122 away from the electrode assembly 22, and the depth H3 of the second limiting groove 23111 is greater than or equal to the protruding height H4 of the second limiting portion 23123 from the side of the first insulating body 23122 away from the electrode assembly 22.

[0242] The depth H3 of the second limiting groove 23111 refers to the dimension of the second limiting groove 23111 along the thickness direction of the first wall body 211, and the protruding height H4 of the second limiting portion 23123 from the side of the first wall body 211 away from the electrode assembly 22 refers to the dimension of the second limiting portion 23123 from the side of the first wall body 211 away from the electrode assembly 22 along the thickness direction of the first wall body 211. Since the depth H3 of the second limiting groove 23111 is greater than or equal to the protruding height H4 of the second limiting portion 23123 from the side of the first wall body 211 away from the electrode assembly 22, in the thickness direction of the first wall body 211, the portion of the second limiting portion 23123 protruding from the side of the first insulating body 23122 away from the first wall body 211 towards the direction of the conductive member 2311 can be entirely accommodated in the second limiting groove 23111, so that the conductive member 2311 can be attached to the side of the first insulating body 23122 away from the first wall body 211.

[0243] By adopting the above technical solution, the second limiting portion 23123 is entirely accommodated in the first limiting groove 23121, effectively improving the situation that the conductive member 2311 is lifted by the second limiting portion 23123, and enabling the conductive member 2311 and the first insulating body 23122 to be attached to each other, thereby facilitating the assembly of the battery monomer 20.

[0244] In some embodiments of the present application, referring to FIG. 17, the difference between the depth H3 of the second limiting groove 23111 and the protruding height H4 of the second limiting portion 23123 from the side of the first insulating body 23122 away from the electrode assembly 22 is 0mm-0.5mm.

[0245] The difference between the depth H3 of the second limiting groove 23111 and the protruding height H4 of the first limiting portion 244 from the side of the first wall body 211 away from the electrode assembly 22 can be selected and set within the above range according to actual application needs, and can be specifically 0mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, etc.

[0246] By adopting the above technical solution, not only is the situation that the conductive member 2311 is lifted by the second limiting portion 23123 effectively improved, but also the depth of the second limiting groove 23111 can be optimized, so that the conductive member 2311 has sufficient structural strength.

[0247] In some embodiments of the present application, referring to FIG. 16, the electrode terminal 23 further comprises a second connecting member 232, and the terminal body 231 and the first wall body 211 are connected through the second connecting member 232.

[0248] The second connecting member 232 is a component for connecting the terminal body 231 and the first wall body 211. The second connecting member 232 can be connected to the terminal body 231 and the first wall body 211 in a manner such as, but not limited to, riveting, screwing, and the like.

[0249] In some embodiments, the second connecting member 232 is made of an electrically conductive material, the first wall body 211 is provided with an electrode lead-out hole 2112, a portion of the second connecting member 232 is arranged inside the housing 21 and used for electrically connecting the electrode assembly 22, and another portion of the second connecting member 232 extends outside the housing 21 through the electrode lead-out hole 2112 and is used for connecting the terminal body 231. As an example, the terminal body 231 includes an electrically conductive member 2311 and a first insulating member 2312 arranged between the electrically conductive member 2311 and the first wall body 211, and the portion of the second connecting member 232 extending outside the housing 21 is connected to the electrically conductive member 2311.

[0250] By using the above technical solution, the terminal body 231 and the first wall body 211 can be easily connected.

[0251] In some embodiments of the present application, referring to FIG. 16, the second connecting member 232 includes a third clamping portion 2321, a fourth clamping portion 2322, and a third connecting portion 2323 connected between the third clamping portion 2321 and the fourth clamping portion 2322, the third clamping portion 2321 and the fourth clamping portion 2322 are arranged opposite to each other along the thickness direction of the first wall body 211 and cooperate to clamp the terminal body 231 and the first wall body 211.

[0252] The third clamping portion 2321 and the fourth clamping portion 2322 are arranged opposite to each other along the thickness direction of the first wall body 211, the third clamping portion 2321, the fourth clamping portion 2322, and the third connecting portion 2323 define a second clamping gap 2324, at least a portion of the first wall body 211 and at least a portion of the terminal body 231 are inserted into the second clamping gap 2324, the third clamping portion 2321 is pressed against a side of the first wall body 211 away from the terminal body 231, and the fourth clamping portion 2322 is pressed against a side of the terminal body 231 away from the first wall body 211, so that the third clamping portion 2321 and the fourth clamping portion 2322 cooperate to clamp and fix the terminal body 231 and the first wall body 211, thereby achieving fixed connection of the terminal body 231 and the first wall body 211.

[0253] In some embodiments, the first wall body 211 is provided with an electrode lead-out hole 2112, the third connecting portion 2323 is arranged in the electrode lead-out hole 2112 and connected between the third clamping portion 2321 and the fourth clamping portion 2322, the third clamping portion 2321 is pressed against the hole edge of the electrode lead-out hole 2112 away from the terminal body 231, and the fourth clamping portion 2322 is pressed against the side of the terminal body 231 away from the first wall body 211, so that the third clamping portion 2321 and the fourth clamping portion 2322 cooperatively clamp and fix the terminal body 231 and the first wall body 211.

[0254] In some embodiments, the terminal body 231 comprises a conductive part 2311 and a first insulating part 2312, the first insulating part 2312 is arranged between the conductive part 2311 and the first wall body 211, the battery cell 20 further comprises a second insulating part 28 arranged on the side of the first wall body 211 facing the electrode assembly 22, the second insulating part 28 is used to insulate and separate the first wall body 211, the first connecting part 24, the deformable part 25 and other components from the electrode assembly 22, and the third clamping portion 2321 and the fourth clamping portion 2322 cooperatively clamp the second insulating part 28, the first wall body 211, the first insulating part 2312 and the conductive part 2311.

[0255] As an example, as shown in FIG. 13 and FIG. 16, the first insulating part 2312 comprises a first insulating body 23122 and an insulating boss 23124, the insulating boss 23124 is protruded on the side of the first insulating body 23122 facing the electrode assembly 22 and arranged around the third connecting portion 2323, so as to insulate and separate the third connecting portion 2323 from the hole wall of the electrode lead-out hole 2112, the side of the first insulating body 23122 facing the electrode assembly 22 is provided with a communication groove 23125, the communication groove 23125 extends from the insulating boss 23124 to the edge side of the first insulating body 23122 and penetrates through the edge side of the first insulating body 23122, and the battery cell 20 further comprises a third sealing part 29c arranged between the hole wall of the electrode lead-out hole 2112 and the outer circumferential wall of the insulating boss 23124, so as to seal the gap between the hole wall of the electrode lead-out hole 2112 and the outer circumferential wall of the insulating boss 23124.

[0256] The second connecting part 232 can be an integrally formed component, for example, the second connecting part 232 is integrally formed by stamping process. In other embodiments, the third clamping portion 2321, the fourth clamping portion 2322 and the third connecting portion 2323 can be respectively formed and then connected into one whole, for example, the third clamping portion 2321, the fourth clamping portion 2322 and the third connecting portion 2323 are welded into one whole.

[0257] By using the above technical solutions, the connection reliability of the terminal body 231 and the first wall body 211 is effectively improved.

[0258] In some embodiments of the present application, referring to FIGS. 9, 16 and 17, the first connecting member 24 is provided with a third limiting groove 248, and at least part of the deformable member 25 is arranged in the third limiting groove 248 and connected with the first connecting member 24.

[0259] The third limiting groove 248 is a structure for limiting the position of the deformable member 25. The third limiting groove 248 can be recessed on the side of the first connecting member 24 facing the electrode assembly 22 along the thickness direction of the first wall body 211, or can be recessed on the side of the first connecting member 24 away from the electrode assembly 22 along the thickness direction of the first wall body 211. The inner peripheral contour shape of the third limiting groove 248 can be adapted to the outer peripheral contour shape of the deformable member 25, for example, the inner peripheral contour shape of the third limiting groove 248 and the outer peripheral contour shape of the deformable member 25 are both circular.

[0260] In some embodiments, the first connecting member 24 includes a first clamping portion 241, a second clamping portion 242, and a first connecting portion 243 connected between the first clamping portion 241 and the second clamping portion 242, the first clamping portion 241 and the second clamping portion 242 cooperate to clamp the first wall body 211, and the third limiting groove 248 is provided on the first connecting portion 243.

[0261] Of course, in other embodiments, the third limiting groove 248 can also be provided on the first clamping portion 241, and can also be provided on the second clamping portion 242.

[0262] In some embodiments, the inner peripheral wall of the third limiting groove 248 can be in close contact with the outer peripheral wall of the deformable member 25 to limit the movement of the deformable member 25 along the direction perpendicular to the thickness direction of the first wall body 211. Of course, considering the manufacturing tolerance, there can be a slight gap between the inner peripheral wall of the third limiting groove 248 and the outer peripheral wall of the deformable member 25.

[0263] By adopting the above technical solution, the relative position of the deformable member 25 and the first connecting member 24 is effectively limited, the risk of gap at the connection between the deformable member 25 and the first connecting member 24 is further reduced, and the working reliability of the deformable member 25 is further improved, and the safety performance of the battery monomer 20 is further improved.

[0264] In some embodiments of the present application, the deformable member 25 is welded with the first connecting member 24.

[0265] The welding of the deformable member 25 and the first connecting member 24 refers to that, under the action of high temperature, at least part of the deformable member 25 and at least part of the first connecting member 24 are melted, and the melted part of the deformable member 25 and the melted part of the first connecting member 24 are combined with each other, and after the melted part of the deformable member 25 and the melted part of the first connecting member 24 are solidified, the deformable member 25 and the first connecting member 24 are connected.

[0266] The welding mode of the deformable member 25 and the first connecting member 24 can be, but is not limited to, laser welding, electric arc welding, ultrasonic welding, etc.

[0267] By adopting the above technical solution, since the material of the deformable member 25 is the same as that of the first connecting member 24, the melted part of the deformable member 25 can be better combined with the melted part of the first connecting member 24 in the welding process, thereby further improving the connection reliability of the deformable member 25 and the first connecting member 24.

[0268] In some embodiments of the present application, referring to FIGS. 4-6, the battery monomer 20 includes two deformable members 25 and two electrode terminals 23 with opposite polarities, the two electrode terminals 23 are insulatively arranged with the first wall body 211, and the two electrode terminals 23 are arranged in one-to-one correspondence with the two deformable members 25.

[0269] It can be understood that one electrode terminal 23 is a positive electrode terminal, and the other electrode terminal 23 is a negative electrode terminal, the positive electrode terminal is electrically connected with the positive electrode lug of the electrode assembly 22, and the negative electrode terminal is electrically connected with the negative electrode lug of the electrode assembly 22.

[0270] The insulatively arranging of the two electrode terminals 23 with the first wall body 211 refers to that insulating structures are arranged between the two electrode terminals 23 and the first wall body 211, and the two insulating structures insulatively separate the two electrode terminals 23 and the first wall body 211.

[0271] The one-to-one correspondence arrangement of the two electrode terminals 23 with the two deformable members 25 refers to that, when the internal pressure of the battery monomer 20 reaches a threshold value, one deformable member 25 deforms under the action of pressure and moves towards the direction close to one electrode terminal 23, and the other deformable member 25 deforms under the action of pressure and moves towards the direction close to the other electrode terminal 23, until the two deformable members 25 are in one-to-one correspondence with the two electrode terminals 23, so that the two electrode terminals 23 are electrically connected with the first wall body 211, thereby cutting off the charge-discharge circuit of the battery monomer 20.

[0272] By adopting the above technical solution, the safety performance of the battery monomer 20 is further improved.

[0273] Of course, in other embodiments, the positive terminal can be insulated from the shell 21, and the negative terminal can be electrically connected to the shell 21, that is, the entire shell 21 can be used as the negative electrode of the battery monomer 20, the number of deformable members 25 is one, in the case where the internal pressure of the battery monomer 20 reaches the threshold value, the deformable member 25 acts in the direction of the positive terminal under the action of the pressure until the deformable member 25 contacts the positive terminal, at this time, the positive electrode and the negative electrode of the battery monomer 20 are short-circuited, thereby cutting off the charge-discharge circuit of the battery monomer 20.

[0274] It can also be that the negative terminal is insulated from the shell 21, and the positive terminal is electrically connected to the shell 21, that is, the entire shell 21 can be used as the positive electrode of the battery monomer 20, the number of deformable members 25 is one, in the case where the internal pressure of the battery monomer 20 reaches the threshold value, the deformable member 25 acts in the direction of the negative terminal under the action of the pressure until the deformable member 25 contacts the negative terminal, at this time, the positive electrode and the negative electrode of the battery monomer 20 are short-circuited, thereby cutting off the charge-discharge circuit of the battery monomer 20.

[0275] In some embodiments of the present application, please refer to FIG. 7 and FIG. 18, the first wall body 211 is provided with a pressure relief hole 2113, the pressure relief hole 2113 penetrates through the opposite sides of the first wall body 211 along the thickness direction, the battery monomer 20 further comprises a third connecting piece 26 and a pressure relief mechanism 27a, the third connecting piece 26 is connected to the first wall body 211, the material of the third connecting piece 26 is different from the material of the first wall body 211, the pressure relief mechanism 27a is covered on the pressure relief hole 2113 and connected to the third connecting piece 26, and the material of the pressure relief mechanism 27a is the same as the material of the third connecting piece 26.

[0276] The third connecting piece 26 is a component for connecting the first wall body 211 and the pressure relief mechanism 27a. Wherein, the connection mode of the third connecting piece 26 and the first wall body 211 can be but not limited to riveting, threaded connection, etc., and the connection mode of the third connecting piece 26 and the pressure relief mechanism 27a can be but not limited to welding, pressure connection, etc.

[0277] The material of the third connecting piece 26 is different from the material of the first wall body 211, which means that the third connecting piece 26 and the first wall body 211 are made of different materials, for example, the third connecting piece 26 is made of aluminum alloy, and the first wall body 211 is made of steel, or for example, the third connecting piece 26 is made of steel, and the first wall body 211 is made of aluminum alloy.

[0278] The pressure relief mechanism 27a is a mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold value. The pressure relief mechanism 27a covers the pressure relief hole 2113 to seal the pressure relief hole 2113, thereby isolating the internal environment of the battery cell 20 from the external environment of the battery cell 20. In the case where the internal pressure or temperature of the battery cell 20 reaches a threshold value, the pressure relief mechanism 27a ruptures under pressure to allow the internal environment of the battery cell 20 to communicate with the external environment of the battery cell 20 through the pressure relief hole 2113, and high-temperature gas can be discharged to the external environment of the battery cell 20 through the pressure relief hole 2113.

[0279] The same material of the pressure relief mechanism 27a and the third connecting piece 26 means that the pressure relief mechanism 27a and the third connecting piece 26 are made of the same material, for example, the pressure relief mechanism 27a and the third connecting piece 26 are both made of aluminum alloy, and for example, the pressure relief mechanism 27a and the third connecting piece 26 are both made of steel.

[0280] In some embodiments, the number of electrode terminals 23 is two, and the pressure relief hole 2113 can be provided between the two electrode terminals 23.

[0281] By using the above technical solution, since the material of the pressure relief mechanism 27a is the same as that of the third connecting piece 26, the material properties of the pressure relief mechanism 27a and the third connecting piece 26 are also the same, which effectively reduces the difference in material state changes of the pressure relief mechanism 27a and the third connecting piece 26 under the influence of environmental factors such as temperature, air pressure, etc., thereby effectively improving the connection reliability of the pressure relief mechanism 27a and the third connecting piece 26, effectively reducing the risk of gaps at the connection between the pressure relief mechanism 27a and the third connecting piece 26, effectively improving the working reliability of the deformable part 25 and the pressure relief mechanism 27a, and further improving the safety performance of the battery cell 20.

[0282] In some embodiments of the present application, please refer to FIG. 14, FIG. 15 and FIG. 18, the third connecting piece 26 includes a fifth clamping part 261, a sixth clamping part 262 and a fourth connecting part 263, the fourth connecting part 263 is connected between the fifth clamping part 261 and the sixth clamping part 262, and the fifth clamping part 261 and the sixth clamping part 262 cooperate to clamp the hole rim of the pressure relief hole 2113.

[0283] The fifth clamping portion 261 and the sixth clamping portion 262 are arranged opposite along the thickness direction of the first wall body 211, and the fifth clamping portion 261, the sixth clamping portion 262 and the fourth connecting portion 263 define a third clamping gap 267, the hole rim of the pressure relief hole 2113 is inserted into the third clamping gap 267, the fifth clamping portion 261 is pressed against one side of the hole rim of the pressure relief hole 2113 along the thickness direction of the first wall body 211, and the sixth clamping portion 262 is pressed against the other side of the hole rim of the pressure relief hole 2113 along the thickness direction of the first wall body 211, so that the fifth clamping portion 261 and the sixth clamping portion 262 cooperatively clamp and fix the hole rim of the pressure relief hole 2113, thereby realizing the fixed connection between the third connecting piece 26 and the first wall body 211.

[0284] In some embodiments, the third connecting piece 26 can be an integrally formed component, for example, the third connecting piece 26 is integrally formed by a stamping process. In other embodiments, the fifth clamping portion 261, the sixth clamping portion 262 and the fourth connecting portion 263 can be respectively formed and then connected into one whole, for example, the fifth clamping portion 261, the sixth clamping portion 262 and the fourth connecting portion 263 are welded into one whole.

[0285] As an example, the pressure relief mechanism 27a can be connected with the fourth connecting portion 263.

[0286] As an example, the pressure relief mechanism 27a can be connected with the fifth clamping portion 261.

[0287] As an example, the pressure relief mechanism 27a can be connected with the sixth clamping portion 262.

[0288] By adopting the above technical solution, the connection reliability of the first wall body 211 and the third connecting piece 26 is effectively improved, the connection tightness of the first wall body 211 and the third connecting piece 26 is increased, the risk of gap at the connection between the first wall body 211 and the third connecting piece 26 is reduced, the situation that the gas generated by the electrode assembly 22 leaks outward from the connection between the first wall body 211 and the third connecting piece 26 is improved, the working reliability of the deformable member 25 and the pressure relief mechanism 27a is further improved, and the safety performance of the battery monomer 20 is further improved.

[0289] In some embodiments of the present application, referring to FIGS. 14, 15 and 18, the third connecting piece 26 is provided with a second through hole 264, the second through hole 264 penetrates through opposite sides of the third connecting piece 26 along the thickness direction of the first wall body 211, and the pressure relief mechanism 27a is arranged on the second through hole 264.

[0290] In some embodiments, the fourth connecting portion 263 has a ring structure, an inner ring space of the fourth connecting portion 263 constitutes the second through hole 264, the fifth clamping portion 261 and the sixth clamping portion 262 are arranged on the outer circumferential side of the fourth connecting portion 263 and surround the second through hole 264, the fifth clamping portion 261 and the sixth clamping portion 262 cooperatively clamp the entire hole rim of the pressure relief hole 2113, and the pressure relief mechanism 27a can be connected to the side of the fourth connecting portion 263 facing the electrode assembly 22 and cover the second through hole 264 to close the pressure relief hole 2113 and the second through hole 264.

[0291] Of course, in other embodiments, the pressure relief mechanism 27a can also be connected to other parts of the fourth connecting portion 263, for example, the pressure relief mechanism 27a is connected to the side of the fourth connecting portion 263 away from the electrode assembly 22, or the pressure relief mechanism 27a is connected to the inner ring wall of the fourth connecting portion 263.

[0292] By adopting the above technical solution, it is convenient to discharge the gas generated by the electrode assembly 22 to the external environment of the battery monomer 20 when the internal pressure of the battery monomer 20 reaches the threshold value.

[0293] In some embodiments of the present application, referring to FIGS. 14, 15 and 18, the third connecting piece 26 is provided with a fourth limiting groove 265, and at least part of the pressure relief mechanism 27a is arranged in the fourth limiting groove 265 and connected with the third connecting piece 26.

[0294] The fourth limiting groove 265 is a structure for limiting the position of the pressure relief mechanism 27a, and the fourth limiting groove 265 can be recessed on the side of the third connecting piece 26 facing the electrode assembly 22 along the thickness direction of the first wall body 211, or can be recessed on the side of the third connecting piece 26 away from the electrode assembly 22 along the thickness direction of the first wall body 211. The inner peripheral contour shape of the fourth limiting groove 265 can be matched with the outer peripheral contour shape of the pressure relief mechanism 27a, for example, the inner peripheral contour shape of the fourth limiting groove 265 and the outer peripheral contour shape of the pressure relief mechanism 27a are both elliptical.

[0295] In some embodiments, the third connecting piece 26 includes a fifth clamping portion 261, a sixth clamping portion 262 and a fourth connecting portion 263, the fourth connecting portion 263 is connected between the fifth clamping portion 261 and the sixth clamping portion 262, the fifth clamping portion 261 and the sixth clamping portion 262 cooperatively clamp the hole rim of the pressure relief hole 2113, and the fourth limiting groove 265 is arranged on the fourth connecting portion 263.

[0296] Of course, in other embodiments, the fourth limiting groove 265 can also be arranged on the fifth clamping portion 261, or can also be arranged on the sixth clamping portion 262.

[0297] In some embodiments, the inner circumferential wall of the fourth limiting groove 265 can be in close contact with the outer circumferential wall of the pressure relief mechanism 27a to limit the movement of the pressure relief mechanism 27a in a direction perpendicular to the thickness direction of the first wall body 211. Of course, in consideration of manufacturing tolerances, there can be a slight gap between the inner circumferential wall of the fourth limiting groove 265 and the outer circumferential wall of the pressure relief mechanism 27a.

[0298] By adopting the above technical solution, the relative position of the pressure relief mechanism 27a and the third connecting piece 26 is effectively limited, further reducing the risk of a gap occurring at the connection between the pressure relief mechanism 27a and the third connecting piece 26, thereby further improving the working reliability of the deformable member 25 and the pressure relief mechanism 27a, and further improving the safety performance of the battery monomer 20.

[0299] In some embodiments of the present application, referring to FIG. 18, the depth H5 of the fourth limiting groove 265 is greater than or equal to the thickness H6 of the pressure relief mechanism 27a.

[0300] The depth H5 of the fourth limiting groove 265 refers to the dimension of the fourth limiting groove 265 in the thickness direction of the first wall body 211. The thickness H6 of the pressure relief mechanism 27a refers to the dimension of the pressure relief mechanism 27a in the thickness direction of the first wall body 211.

[0301] By adopting the above technical solution, the pressure relief mechanism 27a can be entirely arranged within the fourth limiting groove 265, so that the pressure relief mechanism 27a does not protrude outwardly from the fourth limiting groove 265, thereby effectively reducing the risk of damage caused by interference between the pressure relief mechanism 27a and other components of the battery monomer 20, and further improving the safety performance of the battery monomer 20.

[0302] In some embodiments of the present application, referring to FIG. 18, the difference between the depth H5 of the fourth limiting groove 265 and the thickness H6 of the pressure relief mechanism 27a is 0mm-0.5mm.

[0303] The difference between the depth H5 of the fourth limiting groove 265 and the thickness H6 of the pressure relief mechanism 27a can be selected and set within the above range according to actual application needs, and can be 0mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, etc.

[0304] By adopting the above technical solution, the depth dimension of the fourth limiting groove 265 can be optimized under the condition that the pressure relief mechanism 27a does not protrude outwardly from the fourth limiting groove 265, thereby effectively improving the structural strength of the third connecting piece 26.

[0305] In some embodiments of the present application, referring to FIG. 18, the battery cell 20 further comprises a second sealing member 29b arranged between the first wall body 211 and the third connecting member 26 to seal the connection between the first wall body 211 and the third connecting member 26.

[0306] The second sealing member 29b is a component for closing the gap between the first wall body 211 and the third connecting member 26. The second sealing member 29b can be made of a flexible material, which can be but is not limited to rubber, silicone, etc.

[0307] In some embodiments, the third connecting member 26 comprises a fifth clamping portion 261, a sixth clamping portion 262, and a fourth connecting portion 263 connected between the fifth clamping portion 261 and the sixth clamping portion 262, the fifth clamping portion 261 and the sixth clamping portion 262 cooperatively clamping the hole rim of the pressure relief hole 2113. As an example, the second sealing member 29b is arranged between the fifth clamping portion 261 and the hole rim of the pressure relief hole 2113. As an example, the second sealing member 29b is arranged between the sixth clamping portion 262 and the hole rim of the pressure relief hole 2113. As an example, the second sealing member 29b is arranged between the fourth connecting portion 263 and the hole rim of the pressure relief hole 2113. As an example, a part of the second sealing member 29b is arranged between the fifth clamping portion 261 and the hole rim of the pressure relief hole 2113, another part of the second sealing member 29b is arranged between the sixth clamping portion 262 and the hole rim of the pressure relief hole 2113, and yet another part of the second sealing member 29b is arranged between the fourth connecting portion 263 and the hole rim of the pressure relief hole 2113.

[0308] In some embodiments, the fourth connecting portion 263 has a ring structure, the inner ring space of the fourth connecting portion 263 constitutes a second through hole 264, the fifth clamping portion 261 and the sixth clamping portion 262 are protruded on the outer peripheral side of the fourth connecting portion 263 and arranged around the second through hole 264, and the second sealing member 29b has a ring structure and is arranged around the second through hole 264.

[0309] By adopting the above technical solutions, the sealing effect of the connection between the first wall body 211 and the third connecting member 26 is effectively improved, the situation that the gas generated by the electrode assembly 22 leaks outward from the connection between the first wall body 211 and the third connecting member 26 is improved, the working reliability of the deformable member 25 and the pressure relief mechanism 27a is further improved, and the safety performance of the battery cell 20 is further improved.

[0310] In some embodiments of the present application, referring to FIG. 18, the first wall body 211 has a third sealing surface 2115, the third connecting member 26 has a fourth sealing surface 266, the third sealing surface 2115 and the fourth sealing surface 266 cooperatively clamp the second sealing member 29b, and the compression rate of the second sealing member 29b in the direction from the third sealing surface 2115 to the fourth sealing surface 266 is 2%-50%.

[0311] In some embodiments, the second sealing member 29b is arranged between the fifth clamping portion 261 and the hole edge of the pressure relief hole 2113, the surface of the hole edge of the pressure relief hole 2113 facing the fifth clamping portion 261 constitutes the third sealing surface 2115, and the surface of the fifth clamping portion 261 facing the hole edge of the pressure relief hole 2113 constitutes the fourth sealing surface 266.

[0312] In some other embodiments, the second sealing member 29b is arranged between the sixth clamping portion 262 and the hole edge of the pressure relief hole 2113, the surface of the hole edge of the pressure relief hole 2113 facing the fifth clamping portion 261 constitutes the third sealing surface 2115, and the surface of the sixth clamping portion 262 facing the hole edge of the pressure relief hole 2113 constitutes the fourth sealing surface 266.

[0313] In some other embodiments, the second sealing member 29b is arranged between the fourth connecting portion 263 and the hole edge of the pressure relief hole 2113, the surface of the hole edge of the pressure relief hole 2113 facing the fourth connecting portion 263 constitutes the third sealing surface 2115, and the surface of the fourth connecting portion 263 facing the hole edge of the pressure relief hole 2113 constitutes the fourth sealing surface 266.

[0314] The compression rate of the second sealing member 29b refers to the ratio of the size L3 of the second sealing member 29b after compression to the original size of the second sealing member 29b, and it should be noted that the size L3 of the second sealing member 29b after compression refers to the size of the second sealing member 29b in the direction from the third sealing surface 2115 to the fourth sealing surface 266 after being extruded by the first wall body 211 and the third connecting member 26, and the original size of the second sealing member 29b refers to the size of the second sealing member 29b in the direction from the third sealing surface 2115 to the fourth sealing surface 266 before being assembled between the first wall body 211 and the third connecting member 26.

[0315] By adopting the above technical solutions, not only the sealing effect of the connection between the first wall body 211 and the third connecting member 26 is effectively improved, but also the risk of rupture of the second sealing member 29b caused by excessive pressure is reduced, and the reliability of the second sealing member 29b is effectively improved.

[0316] In some embodiments of the present application, the pressure relief mechanism 27a is welded with the third connecting member 26.

[0317] The welding of the pressure relief mechanism 27a with the third connecting member 26 refers to that, under the action of high temperature, at least part of the pressure relief mechanism 27a and at least part of the third connecting member 26 are melted, and the melted parts of the pressure relief mechanism 27a and the third connecting member 26 are combined with each other, and after the melted parts of the pressure relief mechanism 27a and the third connecting member 26 are solidified, the pressure relief mechanism 27a is connected with the third connecting member 26.

[0318] The welding manner of the pressure relief mechanism 27a and the third connecting piece 26 can be, but is not limited to, laser welding, electric arc welding, ultrasonic welding, etc.

[0319] By adopting the above technical solution, since the material of the pressure relief mechanism 27a is the same as that of the third connecting piece 26, the melted part of the pressure relief mechanism 27a can be better combined with the melted part of the third connecting piece 26 in the welding process, thereby further improving the connection reliability of the pressure relief mechanism 27a and the third connecting piece 26.

[0320] In some embodiments of the present application, the third connecting piece 26 is made of aluminum alloy.

[0321] In other words, the third connecting piece 26 is made of aluminum alloy, and correspondingly, the pressure relief mechanism 27a is also made of aluminum alloy.

[0322] By adopting the above technical solution, the connection reliability of the pressure relief mechanism 27a and the third connecting piece 26 is effectively improved.

[0323] In some embodiments of the present application, referring to FIG. 11, the battery monomer 20 further comprises a protective sheet 27b, which is arranged on the side of the first wall body 211 away from the electrode assembly 22 and covers the pressure relief hole 2113.

[0324] The protective sheet 27b is a component for closing the external port of the pressure relief hole 2113 to block foreign matters from entering the pressure relief hole 2113. The protective sheet 27b can be a film piece or a plate piece. The material of the protective sheet 27b can be, but is not limited to, polyimide, polyvinyl chloride, polyester base material, polyurethane, etc.

[0325] By adopting the above technical solution, foreign matters such as electrolyte and dust can be blocked from entering the pressure relief hole 2113, reducing the adverse effects of foreign matters on the pressure relief mechanism 27a, thereby further improving the safety performance of the battery monomer 20.

[0326] In some embodiments of the present application, the protective sheet 27b is bonded to the first wall body 211.

[0327] By adopting the above technical solution, the protective sheet 27b can be fixed on the first wall body 211.

[0328] In some embodiments of the present application, referring to FIG. 6, the above cover body 212 constitutes the first wall body 211, the first wall body 211 is connected with the above shell 213, and the material of the first wall body 211 is the same as that of the shell 213.

[0329] The first wall body 211 and the shell 213 are made of the same material, for example, the shell 213 and the first wall body 211 are made of steel, for example, the shell 213 and the first wall body 211 are made of aluminum alloy.

[0330] By adopting the above technical solution, since the material of the first wall body 211 is the same as that of the shell 213, the material properties of the first wall body 211 and the shell 213 are also the same, effectively reducing the difference in material state changes of the first wall body 211 and the shell 213 under the influence of environmental factors such as temperature, air pressure, etc., thereby effectively improving the connection reliability of the first wall body 211 and the shell 213, effectively reducing the risk of gaps at the connection of the first wall body 211 and the shell 213, and further improving the safety performance of the battery monomer 20.

[0331] In some embodiments of the present application, the shell 213 is welded with the first wall body 211.

[0332] The shell 213 is welded with the first wall body 211, that is, under the action of high temperature, at least part of the shell 213 and at least part of the first wall body 211 are melted, and the melted parts of the shell 213 and the first wall body 211 are combined with each other, and after the melted parts of the shell 213 and the first wall body 211 are solidified, the shell 213 is connected with the first wall body 211.

[0333] The welding method of the shell 213 and the first wall body 211 can be, but is not limited to, laser welding, electric arc welding, ultrasonic welding, etc.

[0334] By adopting the above technical solution, since the material of the first wall body 211 is the same as that of the shell 213, the melted part of the first wall body 211 can be better combined with the melted part of the shell 213 during the welding process, thereby further improving the connection reliability of the first wall body 211 and the shell 213.

[0335] In some embodiments of the present application, the first connecting piece 24 is made of aluminum alloy, and the first wall body 211 is made of steel.

[0336] In other words, the first connecting piece 24 is made of aluminum alloy, the first wall body 211 is made of steel, and correspondingly, the deformable piece 25 is also made of aluminum alloy.

[0337] In the case of equal volume, the weight of the aluminum alloy piece is less than that of the steel piece, and the hardness of the steel piece is greater than that of the aluminum alloy piece. By adopting the above technical solution, not only the connection reliability of the deformable piece 25 and the first connecting piece 24 is improved, but also the structural strength of the first wall body 211 is improved.

[0338] In some embodiments of the present application, referring to FIG. 19, the battery cell 20 further comprises a second insulation member 28 disposed on the side of the first wall body 211 facing the electrode assembly 22, the second insulation member 28 comprising a second insulation body 281 and a first blocking portion 282 connected to the second insulation body 281, the first blocking portion 282 being disposed opposite to the deformable member 25.

[0339] The second insulation member 28 refers to a component made of an insulating material, which can be but is not limited to polyester, epoxy, polyurethane, polybutadiene acid, silicone, polyester imine, and polyimide, etc. The second insulation member 28 is located on the side of the first wall body 211 facing the electrode assembly 22, so as to insulate and separate the first wall body 211, the first connecting member 24, the deformable member 25, the third connecting member 26, the pressure relief mechanism 27a, and other components from the electrode assembly 22, thereby reducing the risk of short circuit.

[0340] The second insulation body 281 is the main part of the second insulation member 28, and is used to insulate and separate the first wall body 211 and the electrode assembly 22. The first blocking portion 282 is connected to the part of the second insulation body 281 opposite to the deformable member 25, and serves to protect the deformable member 25, and also serves to insulate and separate the deformable member 25 from the electrode assembly 22. The first blocking portion 282 and the second insulation body 281 can be an integrally formed component, for example, the first blocking portion 282 and the second insulation body 281 are integrally formed by injection molding process, or the first blocking portion 282 and the second insulation body 281 can be connected to each other to form an integral whole after being formed respectively, for example, the first blocking portion 282 and the second insulation body 281 are bonded.

[0341] By adopting the above technical solution, the deformable member 25 is effectively protected, and the risk of damage caused by interference between the deformable member 25 and other components of the battery cell 20 is effectively reduced.

[0342] In some embodiments of the present application, referring to FIG. 19, the first blocking portion 282 is provided with a first gas hole 2821, and the first gas hole 2821 is used for allowing gas to flow from the electrode assembly 22 to the deformable member 25.

[0343] The first gas hole 2821 penetrates through the first blocking portion 282, so that the gas generated by the electrode assembly 22 can enter the inside of the first blocking portion 282 and flow to the deformable member 25. The number of the first gas hole 2821 can be one or multiple. When the number of the first gas hole 2821 is multiple, the multiple first gas holes 2821 can be uniformly distributed on the first blocking portion 282.

[0344] In some embodiments, the first baffle 282 has a first cavity formed therein, and at least part of the deformable member 25 is accommodated in the first cavity. The first cavity is in communication with the cavity of the shell 213 through the first gas hole 2821, so that the gas generated by the electrode assembly 22 can enter the first cavity and flow to the deformable member 25.

[0345] By using the above technical solution, in the case that the battery cell 20 is overcharged, the gas generated by the electrode assembly 22 can reach the deformable member 25 through the first gas hole 2821 and push the deformable member 25 to move towards the electrode terminal 23, so that the deformable member 25 and the electrode terminal 23 are in contact with each other, thereby cutting off the charging and discharging circuit of the battery cell 20, and further improving the safety performance of the battery cell 20.

[0346] In some embodiments of the present application, referring to FIG. 19, the second insulating member 28 includes a second baffle 283 connected to the second insulating body 281. The second baffle 283 is arranged opposite to the pressure relief mechanism 27a. The second baffle 283 is provided with a second gas hole 2831 for allowing the gas to flow from the electrode assembly 22 to the pressure relief mechanism 27a.

[0347] The second baffle 283 is connected to the part of the second insulating body 281 opposite to the pressure relief mechanism 27a, which serves to protect the pressure relief mechanism 27a and insulate and separate the pressure relief mechanism 27a from the electrode assembly 22. The first baffle 282, the second baffle 283 and the second insulating body 281 can be integrally formed, for example, the first baffle 282, the second baffle 283 and the second insulating body 281 are integrally formed by injection molding process. Alternatively, the first baffle 282, the second baffle 283 and the second insulating body 281 can be separately formed and then connected to form an integral whole, for example, the first baffle 282 and the second baffle 283 are adhered to the second insulating body 281.

[0348] The second gas hole 2831 penetrates through the second baffle 283, so that the gas generated by the electrode assembly 22 can enter the inside of the second baffle 283 and flow to the pressure relief mechanism 27a. The number of the second gas hole 2831 can be one or multiple. In the case that the number of the second gas hole 2831 is multiple, the multiple second gas holes 2831 can be uniformly distributed on the second baffle 283.

[0349] In some embodiments, the second baffle 283 has a second cavity formed therein, and at least part of the pressure relief mechanism 27a is accommodated in the second cavity. The second cavity is in communication with the cavity of the shell 213 through the second gas hole 2831, so that the gas generated by the electrode assembly 22 can enter the second cavity and flow to the pressure relief mechanism 27a.

[0350] By adopting the above technical solution, the protection effect of the pressure relief mechanism 27a is effectively achieved, the risk of damage caused by the interference between the pressure relief mechanism 27a and other components of the battery monomer 20 is effectively reduced, in addition, the gas generated by the electrode assembly 22 can reach the pressure relief mechanism 27a through the second gas hole 2831, so that the pressure relief mechanism 27a is ruptured when the internal pressure of the battery monomer 20 reaches the threshold value, further improving the safety performance of the battery monomer 20.

[0351] In some embodiments of the present application, the battery monomer 20 includes an electrode assembly 22, a shell 21, an electrode terminal 23, a first connecting piece 24, a deformable piece 25, a first sealing piece 29a, a third connecting piece 26, a pressure relief mechanism 27a and a second sealing piece 29b. The shell 21 is used to accommodate the electrode assembly 22, and the shell 21 includes a shell body 213 and a cover body 212, and the cover body 212 constitutes a first wall body 211 of the shell 21. The first wall body 211 is provided with an electrode lead-out hole 2112, a connecting hole 2111 and a pressure relief hole 2113, and the electrode lead-out hole 2112, the connecting hole 2111 and the pressure relief hole 2113 all penetrate through the opposite sides of the first wall body 211 along the thickness direction. The electrode terminal 23 is connected in the electrode lead-out hole 2112 and is used to electrically connect the electrode assembly 22. The deformable piece 25 is configured to be deformable to contact the electrode terminal 23, so that the first wall body 211 is electrically connected with the electrode terminal 23. The first connecting piece 24 includes a first clamping portion 241, a second clamping portion 242 and a first connecting portion 243, the first connecting portion 243 is connected between the first clamping portion 241 and the second clamping portion 242, the first clamping portion 241 and the second clamping portion 242 cooperate to clamp the hole rim of the connecting hole 2111, and the first sealing piece 29a is arranged between the first wall body 211 and the first connecting piece 24. The third connecting piece 26 includes a fifth clamping portion 261, a sixth clamping portion 262 and a fourth connecting portion 263, the fourth connecting portion 263 is connected between the fifth clamping portion 261 and the sixth clamping portion 262, the fifth clamping portion 261 and the sixth clamping portion 262 cooperate to clamp the hole rim of the pressure relief hole 2113, and the second sealing piece 29b is arranged between the first wall body 211 and the third connecting piece 26. The material of the first connecting piece 24, the material of the deformable piece 25, the material of the third connecting piece 26 and the material of the pressure relief mechanism 27a are all aluminum alloy, the deformable piece 25 is welded with the first connecting piece 24, and the pressure relief mechanism 27a is welded with the third connecting piece 26. The material of the first wall body 211 and the material of the shell body 213 are both steel, and the first wall body 211 is welded with the shell body 213.

[0352] By adopting the technical solutions, the connection reliability between the deformable part 25 and the first connecting part 24 and between the pressure relief mechanism 27a and the third connecting part 26 is improved, the connection reliability and sealing effect between the first connecting part 24 and the first wall body 211 and between the third connecting part 26 and the first wall body 211 are improved, and the connection reliability between the shell 213 and the first wall body 211 is improved. In this way, the risk of the gas generated by the electrode assembly 22 being discharged to the external environment of the shell 21 from other parts except the broken part of the pressure relief mechanism 27a is effectively reduced, the working reliability of the deformable part 25 and the pressure relief mechanism 27a is effectively improved, and the safety performance of the battery monomer 20 is effectively improved.

[0353] In a second aspect, referring to FIG. 3, an embodiment of the present application provides a battery 100, which includes the battery monomer 20 of any one of the above embodiments.

[0354] The battery 100 provided by the embodiment of the present application effectively improves the safety performance of the battery 100 because the battery monomer 20 of any one of the above embodiments is used.

[0355] In a third aspect, referring to FIG. 2, an embodiment of the present application provides an energy storage device 2000, which includes the battery 100.

[0356] The energy storage device 2000 provided by the embodiment of the present application effectively improves the safety performance of the energy storage device 2000 because the battery 100 of any one of the above embodiments is used.

[0357] In a fourth aspect, referring to FIG. 1, an embodiment of the present application provides a power consumption device, which includes the battery 100.

[0358] The power consumption device provided by the embodiment of the present application effectively improves the safety performance of the power consumption device because the battery 100 of any one of the above embodiments is used.

[0359] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A battery cell, characterized by, The battery monomer comprises: an electrode assembly; a housing for accommodating the electrode assembly, the housing comprising a first wall body; an electrode terminal for electrically connecting the electrode assembly, the electrode terminal being arranged on the first wall body; a first connecting piece connected with the first wall body, the first connecting piece being made of a material different from that of the first wall body; a deformable piece connected with the first connecting piece, the deformable piece being made of the same material as the first connecting piece, and being configured to be deformable to contact the electrode terminal so as to electrically connect the first wall body and the electrode terminal.

2. The battery cell of claim 1, wherein, The first connecting piece comprises a first clamping portion, a second clamping portion, and a first connecting portion connected between the first clamping portion and the second clamping portion, and the first clamping portion and the second clamping portion are configured to clamp the first wall body.

3. The battery cell of claim 2, wherein, The first wall body is provided with a connecting hole penetrating through the first wall body along opposite sides in the thickness direction, and the first clamping portion and the second clamping portion are configured to clamp the hole rim of the connecting hole.

4. The battery cell according to any one of claims 1-3, characterized in that, The first connecting piece is provided with a first through hole penetrating through the first connecting piece along opposite sides in the thickness direction of the first wall body, and the deformable piece is configured to be deformable to contact the electrode terminal through the first through hole.

5. The battery cell of claim 4, wherein, The deformable piece comprises a second connecting portion connected with the first connecting piece, and a deformation portion configured to be deformable to contact the electrode terminal through the first through hole.

6. The battery cell of claim 5, wherein, The second connecting portion is arranged around the deformation portion and the first through hole.

7. The battery cell according to claim 5 or 6, characterized in that The distance between the deformation portion and the electrode terminal in the thickness direction of the first wall body is 0.2mm-1.5mm.

8. The battery cell of any one of claims 1-7, wherein, The contact area of the deformable member with the electrode terminal is 20 mm 2 - 500 mm 2 .

9. The battery cell of any one of claims 1-8, wherein, The battery monomer further comprises a first sealing piece arranged between the first wall body and the first connecting piece to seal the first wall body and the first connecting piece.

10. The battery cell of claim 9, wherein, The first wall body has a first sealing surface, the first connecting piece has a second sealing surface, and the first sealing surface and the second sealing surface clamp the first sealing piece, and the compression rate of the first sealing piece in the direction from the first sealing surface to the second sealing surface is 2%-50%.

11. The battery cell of any one of claims 1-10, wherein, The electrode terminal comprises a terminal body, and a first limiting structure is arranged between the terminal body and the first connecting piece, the first limiting structure being configured to limit the relative position of the terminal body and the first connecting piece in a preset direction, and the preset direction is not parallel to the thickness direction of the first wall body.

12. The battery cell of claim 11, wherein, The terminal body is concavely provided with a first limiting groove on the side facing the electrode assembly, and the first connecting piece comprises a first limiting portion, at least part of the first limiting portion being arranged in the first limiting groove to form the first limiting structure.

13. The battery cell of claim 12, wherein, The first limiting portion is convexly arranged on the side of the first wall body away from the electrode assembly, and the depth of the first limiting groove is greater than or equal to the protruding height of the first limiting portion from the side of the first wall body away from the electrode assembly.

14. The battery cell of claim 13, wherein, The difference between the depth of the first limiting groove and the protruding height of the first limiting portion from the side of the first wall body away from the electrode assembly is 0mm-0.5mm.

15. The battery cell of any one of claims 11-14, wherein, The terminal body comprises a conductive part and a first insulating part, the deformable part is configured to be deformable to contact the conductive part, the first insulating part is arranged between the conductive part and the first wall body, and the first limiting structure is arranged between the first insulating part and the first connecting part.

16. The battery cell of claim 15, wherein, A second limiting structure is arranged between the conductive part and the first insulating part, and is used to limit the relative position of the conductive part and the first insulating part in the preset direction.

17. The battery cell of claim 16, wherein, A second limiting groove is recessed on the side of the conductive part facing the first insulating part, the first insulating part comprises a first insulating body and a second limiting portion, the first insulating body is arranged between the conductive part and the first wall body, and at least part of the second limiting portion is arranged in the second limiting groove to form the second limiting structure.

18. The battery cell of claim 17, wherein, The second limiting portion is protruded on the side of the first insulating body away from the electrode assembly, and the depth of the second limiting groove is greater than or equal to the protruding height of the second limiting portion from the side of the first insulating body away from the electrode assembly.

19. The battery cell of claim 18, wherein, The difference between the depth of the second limiting groove and the protruding height of the second limiting portion from the side of the first insulating body away from the electrode assembly is 0mm-0.5mm.

20. The battery cell of any one of claims 11-19, wherein, The electrode terminal further comprises a second connecting part, and the terminal body and the first wall body are connected through the second connecting part.

21. The battery cell of claim 20, wherein, The second connecting part comprises a third clamping portion, a fourth clamping portion and a third connecting portion, the third connecting portion is connected between the third clamping portion and the fourth clamping portion, and the third clamping portion and the fourth clamping portion are used to clamp the terminal body and the first wall body.

22. The battery cell of any one of claims 1-21, wherein, The first connecting part is provided with a third limiting groove, and at least part of the deformable part is arranged in the third limiting groove and connected with the first connecting part.

23. The battery cell of any one of claims 1-22, wherein, The deformable part is welded with the first connecting part.

24. The battery cell of any one of claims 1-23, wherein, The battery monomer comprises two electrode terminals with opposite polarities and two deformable parts, and the two electrode terminals and the two deformable parts are arranged one by one.

25. The battery cell of any one of claims 1-24, wherein, The first wall body is provided with a pressure relief hole, the pressure relief hole penetrates through opposite sides of the first wall body along the thickness direction, the battery monomer further comprises a third connecting part and a pressure relief mechanism, the third connecting part is connected with the first wall body, the material of the third connecting part is different from the material of the first wall body, the pressure relief mechanism is arranged on the pressure relief hole and connected with the third connecting part, and the material of the pressure relief mechanism is the same as that of the third connecting part.

26. The battery cell of claim 25, wherein, The third connecting part comprises a fifth clamping portion, a sixth clamping portion and a fourth connecting portion, the fourth connecting portion is connected between the fifth clamping portion and the sixth clamping portion, and the fifth clamping portion and the sixth clamping portion are used to clamp the hole rim of the pressure relief hole.

27. The battery cell of claim 25 or 26, wherein, The third connecting part is provided with a second through hole, the second through hole penetrates through opposite sides of the third connecting part along the thickness direction of the first wall body, and the pressure relief mechanism is arranged on the second through hole.

28. The battery cell of any one of claims 25-27, wherein, The third connecting piece is provided with a fourth limiting slot, and at least part of the pressure relief mechanism is arranged in the fourth limiting slot and connected with the third connecting piece.

29. The battery cell of claim 28, wherein, The fourth limiting slot has a depth greater than or equal to the thickness of the pressure relief mechanism.

30. The battery cell of claim 29, wherein, The difference between the depth of the fourth limiting slot and the thickness of the pressure relief mechanism is 0 mm-0.5 mm.

31. The battery cell of any one of claims 25-30, wherein, The battery monomer further comprises a second sealing piece arranged between the first wall body and the third connecting piece to seal the first wall body and the third connecting piece.

32. The battery cell of claim 31, wherein, The first wall body has a third sealing surface, the third connecting piece has a fourth sealing surface, the third sealing surface and the fourth sealing surface cooperate to clamp the second sealing piece, and the compression rate of the second sealing piece in the direction from the third sealing surface to the fourth sealing surface is 2%-50%.

33. The battery cell of any one of claims 25-32, wherein, The pressure relief mechanism is welded with the third connecting piece.

34. The battery cell of any one of claims 25-33, wherein, The third connecting piece is made of aluminum alloy.

35. The battery cell of any one of claims 25-34, wherein, The battery monomer further comprises a protective sheet arranged on the side of the first wall body away from the electrode assembly and covering the pressure relief hole.

36. The battery cell of claim 35, wherein, The protective sheet is bonded to the first wall body.

37. The battery cell of any one of claims 1-36, wherein, The shell comprises a shell body and a cover arranged on the shell body, the cover constitutes the first wall body, the first wall body is connected with the shell body, and the material of the first wall body is the same as that of the shell body.

38. The battery cell of claim 37, wherein, The shell body is welded with the first wall body.

39. The battery cell of any one of claims 1-38, wherein, The first connecting piece is made of aluminum alloy, and the first wall body is made of steel.

40. The battery cell of any one of claims 1-39, wherein, The battery monomer further comprises a second insulating piece arranged on the side of the first wall body facing the electrode assembly, the second insulating piece comprises a second insulating body and a first blocking part connected with the second insulating body, and the first blocking part is arranged opposite to the deformable piece.

41. The battery cell of claim 40, wherein, The first blocking part is provided with a first gas hole for gas to flow from the electrode assembly to the deformable piece.

42. A battery, comprising: The battery comprises the battery monomer according to any one of claims 1-41.

43. An energy storage device, comprising: The energy storage device comprises the battery according to claim 42.

44. An electrical device, comprising: The electric device comprises the battery according to claim 42.

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