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), and a deformable member (25), wherein the casing (21) comprises a first wall (211), and the deformable member (25) is configured to deform to come into contact with the electrode terminal (23), thus electrically connecting the first wall (211) to the electrode terminal (23). The material of the deformable member (25) is different from that of the first wall (211). The deformable member (25) is fixedly connected to the first wall (211), and a first connecting material (24) is provided at the fixed connection area between the deformable member (25) and the first wall (211), the melting point of the first connecting material (24) being lower than the melting point of the material of the deformable member (25) and / or the melting point of the material of the first wall (211).

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. 202410850398.1, 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 battery, 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 usually includes a battery cell. In the development process 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 shell for accommodating the electrode assembly, the shell 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 deformable member configured to be deformable to contact the electrode terminal to electrically connect the first wall body and the electrode terminal, the material of the deformable member and the material of the first wall body being different;

[0013] The deformable member is fixedly connected with the first wall body, and the first connecting material is included at the fixed connection between the deformable member and the first wall body, the melting point of the first connecting material being lower than the melting point of the material of the deformable member and / or the melting point of the material of the first wall body.

[0014] The battery monomer provided by the embodiments of the present application has the beneficial effects that: the battery monomer provided by the embodiments of the present application is provided with a first connecting material at the fixed connection between the deformable member and the first wall body. Since the melting point of the first connecting material is lower than the melting points of the material of the deformable member and / or the material of the first wall body, when the preset temperature is reached, the first connecting material will melt first, and after the first connecting material solidifies, the deformable member and the first wall body will be adhered together, so as to realize the fixed connection of the deformable member and the first wall body. Compared with the connection mode of directly combining the melting part of the deformable member and the melting part of the first wall body, the connection reliability of the deformable member and the first wall body is effectively improved, the risk of a gap at the connection between the deformable member and the first wall body due to different materials is reduced, and thus the working reliability of the deformable member is effectively improved, so that the deformable member can act in time in the case of overcharging of the battery monomer, cut off the charging and discharging circuit of the battery monomer, and thus the safety performance of the battery monomer is effectively improved.

[0015] In some embodiments of the present application, the first connecting material is solder.

[0016] By adopting the above technical solution, the connection reliability of the deformable member and the first wall body is further improved.

[0017] In some embodiments of the present application, the deformable member and the first wall body cooperatively define a first connecting groove, and the first connecting material is accommodated in the first connecting groove and adhered to the inner surface of the first connecting groove.

[0018] By adopting the above technical solution, not only the position of the first connecting material is effectively limited, but also the adhesion area of the first connecting material is effectively increased, so as to further improve the connection reliability of the deformable member and the first wall body.

[0019] In some embodiments of the present application, the first wall body has a first connecting surface, the deformable member has a second connecting surface, the first connecting material is connected between the first connecting surface and the second connecting surface, and the first connecting surface and / or the second connecting surface is a curved surface.

[0020] By adopting the above technical solution, the adhesion area of the first connecting material is effectively increased, so as to further improve the connection reliability of the deformable member and the first wall body.

[0021] In some embodiments of the present application, the first wall body has a first connecting surface, the deformable member has a second connecting surface, the first connecting material is connected between the first connecting surface and the second connecting surface, and the first connecting surface and / or the second connecting surface is a rough surface.

[0022] By adopting the above technical solution, the adhesion of the first connecting material on the first connecting surface and the second connecting surface is effectively improved, so as to further improve the connection reliability of the deformable member and the first wall body.

[0023] In some embodiments of the present application, the first connecting material is arranged around the deformable member.

[0024] By adopting the above technical solution, the deformable member and the first wall body can be connected along the circumference of the deformable member by the first connecting material, so that an annular sealing boundary is formed between the deformable member and the first wall body, not only effectively sealing the gap between the deformable member and the first wall body, but also making the stress of the deformable member more uniform, thereby further improving the connection reliability of the deformable member and the first wall body.

[0025] In some embodiments of the present application, a first limiting structure is arranged between the first wall body and the deformable member, and the first limiting structure is used to limit the relative position of the first wall body and the deformable member along a direction perpendicular to the thickness direction of the first wall body.

[0026] By adopting the above technical solution, the relative position of the first wall body and the deformable member along a direction perpendicular to the thickness direction of the first wall body is effectively limited, thereby effectively reducing the risk of fracture of the fixed connection between the deformable member and the first wall body due to displacement of the deformable member, thereby further improving the working reliability of the deformable member and further improving the safety performance of the battery cell.

[0027] In some embodiments of the present application, the first limiting structure includes a first limiting portion, and the first limiting portion is arranged on the first wall body and abuts against the deformable member along a direction perpendicular to the thickness direction of the first wall body, so as to limit the relative position of the first wall body and the deformable member along a direction perpendicular to the thickness direction of the first wall body.

[0028] By adopting the above technical solution, the first limiting structure is effectively simplified, and the relative position of the first wall body and the deformable member along a direction perpendicular to the thickness direction of the first wall body is limited.

[0029] In some embodiments of the present application, the first limiting portion is arranged protruding from the first wall body along the thickness direction of the first wall body, and the protruding height of the first limiting portion from the first wall body is 0.1mm-0.6mm.

[0030] By adopting the above technical solution, not only the relative position of the first wall body and the deformable member along a direction perpendicular to the thickness direction of the first wall body is effectively limited, but also the condition that the first limiting portion occupies too much space due to the too large protruding height of the first limiting portion is improved, thereby effectively improving the volume energy density of the battery cell.

[0031] In some embodiments of the present application, the first wall body is provided with a via hole penetrating through opposite sides of the first wall body along the thickness direction, and the deformable member is configured to be deformable to contact the electrode terminal through the via hole, so that the first wall body is electrically connected with the electrode terminal.

[0032] By adopting the technical scheme, the deformable member is facilitated to contact the electrode terminal.

[0033] In some embodiments of the present application, the deformable member comprises a connecting portion and a deformation portion, the connecting portion is arranged to be fixedly connected with the first wall body, the connecting portion surrounds the deformation portion and the via hole, and the deformation portion is configured to be deformable to contact the electrode terminal through the via hole, so that the first wall body is electrically connected with the electrode terminal.

[0034] By adopting the technical scheme, the deformable member is facilitated to contact the electrode terminal.

[0035] In some embodiments of the present application, the electrode terminal is provided with a protruding portion protruding towards the deformable member at the via hole, and the deformable member is configured to be deformable to contact the protruding portion through the via hole, so that the first wall body is electrically connected with the electrode terminal.

[0036] By adopting the technical scheme, the deformable member is facilitated to contact the electrode terminal.

[0037] In some embodiments of the present application, the battery monomer further comprises a first sealing member arranged between the first wall body and the deformable member to seal the connection between the first wall body and the deformable member.

[0038] By adopting the technical scheme, the sealing effect of the connection between the first wall body and the deformable member is effectively improved, thereby further improving the working reliability of the deformable member and further improving the safety performance of the battery monomer.

[0039] In some embodiments of the present application, the first sealing member surrounds the via hole.

[0040] By adopting the technical scheme, the communication path between the via hole and the internal environment of the shell is effectively blocked, the sealing effect of the connection between the first wall body and the deformable member is further improved, thereby further improving the working reliability of the deformable member and further improving the safety performance of the battery monomer.

[0041] In some embodiments of the present application, the first wall body and the deformable member clamp the first sealing member along the thickness direction of the first wall body, at least one of the first wall body and the deformable member is provided with a second limiting structure for limiting the movement of the first sealing member along a direction perpendicular to the thickness direction of the first wall body.

[0042] By adopting the technical scheme, the risk of sealing failure caused by displacement of the first sealing member along a direction perpendicular to the thickness direction of the first wall body is effectively reduced, the sealing effect of the connection between the first wall body and the deformable member is further improved, thereby further improving the working reliability of the deformable member and further improving the safety performance of the battery monomer.

[0043] In some embodiments of the present application, the second limiting structure comprises a second limiting portion arranged on the first wall body and abutting against the first sealing member in a direction perpendicular to the thickness direction of the first wall body, so as to limit the movement of the first sealing member in the direction perpendicular to the thickness direction of the first wall body.

[0044] By adopting the above technical solution, the second limiting structure is effectively simplified, and the position of the first sealing member in the direction perpendicular to the thickness direction of the first wall body is conveniently limited.

[0045] In some embodiments of the present application, the second limiting portion is arranged protruding from the first wall body in the thickness direction of the first wall body, and the protruding height of the second limiting portion from the first wall body is 0.1mm-0.6mm.

[0046] By adopting the above technical solution, not only the position of the first sealing member is effectively limited, but also the condition that the second limiting portion occupies too much space due to the too large protruding height of the second limiting portion is improved, so that the volume energy density of the battery monomer is effectively improved.

[0047] In some embodiments of the present application, the first wall body has a first sealing surface, the deformable member has a second sealing surface, the first sealing surface and the second sealing surface cooperate to clamp the first sealing member, and in the direction from the first sealing surface to the second sealing surface, the compression rate of the first sealing member is 2%-50%.

[0048] By adopting the above technical solution, not only the sealing effect of the connection between the first wall body and the deformable member is effectively improved, but also the risk of rupture of the first sealing member due to too large pressure is reduced, so that the reliability of the first sealing member is effectively improved.

[0049] 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 insulation with the first wall body, and the two electrode terminals are arranged in one-to-one correspondence with the two deformable members.

[0050] By adopting the above technical solution, the safety performance of the battery monomer is further improved.

[0051] In some embodiments of the present application, the battery monomer further comprises a first insulating member arranged between the electrode terminal and the first wall body, so as to insulate the electrode terminal from the first wall body.

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

[0053] In some embodiments of the present application, the first wall body is provided with a pressure relief hole penetrating through opposite sides of the first wall body along the thickness direction, the battery monomer further comprises a pressure relief mechanism, the pressure relief mechanism covers the pressure relief hole, the material of the pressure relief mechanism is different from the material of the first wall body, the pressure relief mechanism is fixedly connected with the first wall body, and a second connecting material is included at the fixed connection between the pressure relief mechanism and the first wall body, the melting point of the second connecting material is lower than the melting points of the material of the pressure relief mechanism and / or the material of the first wall body.

[0054] By adopting the above technical solution, the connection reliability of the pressure relief mechanism and the first wall body is effectively improved, the risk of a gap being generated at the connection between the pressure relief mechanism and the first wall body due to different materials is reduced, the working reliability of the pressure relief mechanism is effectively improved, and the safety performance of the battery monomer is effectively improved.

[0055] In some embodiments of the present application, the second connecting material is solder.

[0056] By adopting the above technical solution, the connection reliability of the pressure relief mechanism and the first wall body is further improved.

[0057] In some embodiments of the present application, the pressure relief mechanism and the first wall body cooperatively define a second connecting groove, and the second connecting material is accommodated in the second connecting groove and adheres to the inner surface of the second connecting groove.

[0058] By adopting the above technical solution, not only is the position of the second connecting material effectively limited, but also the adhesion area of the second connecting material is effectively increased, thereby further improving the connection reliability of the pressure relief mechanism and the first wall body.

[0059] In some embodiments of the present application, the first wall body has a third connecting surface, the pressure relief mechanism has a fourth connecting surface, the second connecting material is connected between the third connecting surface and the fourth connecting surface, and the third connecting surface and / or the fourth connecting surface is a curved surface.

[0060] By adopting the above technical solution, the adhesion area of the second connecting material is effectively increased, thereby further improving the connection reliability of the pressure relief mechanism and the first wall body.

[0061] In some embodiments of the present application, the first wall body has a third connecting surface, the pressure relief mechanism has a fourth connecting surface, the second connecting material is connected between the third connecting surface and the fourth connecting surface, and the third connecting surface and / or the fourth connecting surface is a rough surface.

[0062] By adopting the above technical solution, the adhesion of the second connecting material on the third connecting surface and the fourth connecting surface is effectively improved, thereby further improving the connection reliability of the pressure relief mechanism and the first wall body.

[0063] In some embodiments of the present application, the second connecting material is arranged around the pressure relief mechanism.

[0064] By adopting the above technical solution, the pressure relief mechanism and the first wall body are connected along the circumferential direction of the pressure relief mechanism by the second connecting material, so that an annular sealing boundary is formed between the pressure relief mechanism and the first wall body, which not only effectively seals the gap between the pressure relief mechanism and the first wall body, but also makes the stress of the pressure relief mechanism more uniform, thereby further improving the connection reliability of the pressure relief mechanism and the first wall body.

[0065] In some embodiments of the present application, a third limiting structure is arranged between the first wall body and the pressure relief mechanism, and the third limiting structure is used to limit the relative position of the first wall body and the pressure relief mechanism along a direction perpendicular to the thickness direction of the first wall body.

[0066] By adopting the above technical solution, the relative position of the first wall body and the pressure relief mechanism along a direction perpendicular to the thickness direction of the first wall body is effectively limited, thereby effectively reducing the risk of fracture of the fixed connection between the pressure relief mechanism and the first wall body due to displacement of the pressure relief mechanism, thereby further improving the working reliability of the pressure relief mechanism and further improving the safety performance of the battery cell.

[0067] In some embodiments of the present application, the third limiting structure includes a third limiting portion, and the third limiting portion is arranged on the first wall body and abuts against the pressure relief mechanism along a direction perpendicular to the thickness direction of the first wall body, so as to limit the relative position of the first wall body and the pressure relief mechanism along a direction perpendicular to the thickness direction of the first wall body.

[0068] By adopting the above technical solution, the third limiting structure is effectively simplified, and the relative position of the first wall body and the pressure relief mechanism along a direction perpendicular to the thickness direction of the first wall body is limited.

[0069] In some embodiments of the present application, the third limiting portion is arranged protruding from the first wall body along the thickness direction of the first wall body, and the protruding height of the third limiting portion from the first wall body is 0.1mm-0.6mm.

[0070] By adopting the above technical solution, not only is the relative position of the first wall body and the pressure relief mechanism along a direction perpendicular to the thickness direction of the first wall body effectively limited, but also the condition that the third limiting portion occupies too much space due to the excessive protruding height of the third limiting portion is improved, thereby effectively improving the volume energy density of the battery cell.

[0071] In some embodiments of the present application, the battery cell further comprises a second sealing member arranged between the first wall body and the pressure relief mechanism to seal the connection between the first wall body and the pressure relief mechanism.

[0072] By adopting the technical scheme, the sealing effect of the connection between the first wall body and the pressure relief mechanism is effectively improved, the working reliability of the pressure relief mechanism is further improved, and the safety performance of the battery monomer is further improved.

[0073] In some embodiments of the present application, the second sealing member surrounds the pressure relief hole.

[0074] By adopting the technical scheme, the communication path between the pressure relief hole and the internal environment of the shell is effectively blocked, the sealing effect of the connection between the first wall body and the pressure relief mechanism is further improved, the working reliability of 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 and the pressure relief mechanism clamp the second sealing member along the thickness direction of the first wall body, and at least one of the first wall body and the pressure relief mechanism is provided with a fourth limiting structure for limiting the movement of the second sealing member in a direction perpendicular to the thickness direction of the first wall body.

[0076] By adopting the technical scheme, the risk of sealing failure caused by displacement of the second sealing member in a direction perpendicular to the thickness direction of the first wall body is effectively reduced, the sealing effect of the connection between the first wall body and the pressure relief mechanism is further improved, the working reliability of the pressure relief mechanism is further improved, and the safety performance of the battery monomer is further improved.

[0077] In some embodiments of the present application, the fourth limiting structure includes a fourth limiting portion arranged on the first wall body and abutting against the second sealing member in a direction perpendicular to the thickness direction of the first wall body to limit the movement of the second sealing member in the direction perpendicular to the thickness direction of the first wall body.

[0078] By adopting the technical scheme, the fourth limiting structure is effectively simplified, and the position of the second sealing member in a direction perpendicular to the thickness direction of the first wall body is limited.

[0079] In some embodiments of the present application, the fourth limiting portion is arranged protruding from the first wall body along the thickness direction of the first wall body, and the protruding height of the fourth limiting portion from the first wall body is 0.1-0.6mm.

[0080] By adopting the technical scheme, not only the position of the second sealing member is effectively limited, but also the condition that the fourth limiting portion occupies too much space due to the excessive protruding height of the fourth limiting portion is improved, thereby effectively improving the volume energy density of the battery monomer.

[0081] In some embodiments of the present application, the first wall body has a third sealing surface, the pressure relief mechanism has a fourth sealing surface, the third sealing surface and the fourth sealing surface cooperate to clamp the second sealing member, and the compression rate of the second sealing member in the direction from the third sealing surface to the fourth sealing surface is 2% to 50%.

[0082] By adopting the above technical solutions, not only the sealing effect of the connection between the first wall body and the pressure relief mechanism is effectively improved, but also the risk of rupture of the second sealing member due to excessive pressure is reduced, and the reliability of the second sealing member is effectively improved.

[0083] In some embodiments of the present application, the pressure relief mechanism is made of aluminum alloy.

[0084] By adopting the above technical solutions, the pressure relief mechanism is facilitated to open and release the internal pressure of the battery monomer when the internal pressure of the battery monomer reaches a threshold value, thereby further improving the safety performance of the battery monomer.

[0085] In some embodiments of the present application, the battery monomer further comprises a protective sheet, the protective sheet is arranged on the side of the first wall body away from the electrode assembly and covers the pressure relief hole, and the pressure relief mechanism is arranged on the side of the first wall body facing the electrode assembly.

[0086] By adopting the above technical solutions, foreign matters such as electrolyte and dust are prevented from entering the pressure relief hole, thereby reducing the adverse effects of foreign matters on the pressure relief mechanism, and further improving the safety performance of the battery monomer.

[0087] In some embodiments of the present application, the protective sheet is bonded to the first wall body.

[0088] By adopting the above technical solutions, the protective sheet is facilitated to be fixed on the first wall body.

[0089] In some embodiments of the present application, the housing comprises a shell and a cover body covering the shell, the cover body constitutes the first wall body, the first wall body is connected with the shell, and the material of the first wall body is the same as that of the shell.

[0090] By adopting the above technical solutions, since the material of the first wall body is the same as that of the shell, the material properties of the first wall body are also the same as those of the shell, thereby effectively reducing the difference in material state changes of the first wall body and the shell under the influence of environmental factors such as temperature and air pressure, effectively improving the connection reliability of the first wall body and the shell, effectively reducing the risk of gaps at the connection between the first wall body and the shell, and further improving the safety performance of the battery monomer.

[0091] In some embodiments of the present application, the shell and the first wall body are welded.

[0092] By adopting the technical scheme, since the material of the first wall body is the same as that of the shell, the melted part of the first wall body can be better combined with the melted part of the shell in the welding process, thereby further improving the connection reliability of the first wall body and the shell.

[0093] In some embodiments of the present application, the deformable member is made of aluminum, and the first wall body is made of steel.

[0094] By adopting the technical scheme, not only the connection reliability of the deformable member and the first wall body is improved, but also the structural strength of the first wall body is improved.

[0095] In some embodiments of the present application, the battery monomer further comprises a second insulation member arranged on the side of the first wall body facing the electrode assembly, the second insulation member comprising an insulation main body and a first blocking portion connected to the insulation main body, and the first blocking portion is arranged opposite to the deformable member.

[0096] By adopting the technical scheme, the deformable member is effectively protected, and the risk of damage caused by interference between the deformable member and other components in the battery monomer is effectively reduced.

[0097] In some embodiments of the present application, the first blocking portion is provided with a first gas hole, and the first gas hole is used for allowing gas to flow from the electrode assembly to the deformable member.

[0098] By adopting the technical scheme, in the case that the battery monomer is overcharged, the gas generated by the electrode assembly can reach the deformable member through the first gas hole and push the deformable member to move towards the electrode terminal, so that the deformable member and the electrode terminal are in contact with each other, thereby cutting off the charge-discharge circuit of the battery monomer, and further improving the safety performance of the battery monomer.

[0099] The embodiments of the present application further provide a battery comprising the battery monomer of any one of the above embodiments.

[0100] The battery provided by the embodiments of the present application has the beneficial effect that the safety performance of the battery is effectively improved due to the adoption of the battery monomer of any one of the above embodiments.

[0101] The embodiments of the present application further provide an energy storage device comprising the battery.

[0102] The energy storage device provided by the embodiments of the present application has the beneficial effect that the safety performance of the energy storage device is effectively improved due to the adoption of the battery of any one of the above embodiments.

[0103] The embodiments of the present application further provide an electric equipment comprising the battery.

[0104] The power utilization equipment provided by the embodiments of the present application has the beneficial effect that the power utilization equipment provided by the embodiments of the present application effectively improves the safety performance of the power utilization equipment due to the adoption of the battery of any one of the above embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0105] 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.

[0106] FIG. 1 is a structural schematic diagram of a vehicle provided by an embodiment of the present application;

[0107] FIG. 2 is a structural schematic diagram of an energy storage device provided by an embodiment of the present application;

[0108] FIG. 3 is an exploded schematic diagram of a battery provided by an embodiment of the present application;

[0109] FIG. 4 is a structural schematic diagram of a battery monomer provided by an embodiment of the present application;

[0110] FIG. 5 is a top view schematic diagram of the battery monomer shown in FIG. 4;

[0111] FIG. 6 is a sectional view structural schematic diagram of the battery monomer shown in FIG. 5 along the direction of line A-A;

[0112] FIG. 7 is an enlarged structural schematic diagram of B of the battery monomer shown in FIG. 6;

[0113] FIG. 8 is an enlarged structural schematic diagram of D of the battery monomer shown in FIG. 7;

[0114] FIG. 9 is an enlarged structural schematic diagram of C of the battery monomer shown in FIG. 6;

[0115] FIG. 10 is an enlarged structural schematic diagram of E of the battery monomer shown in FIG. 9;

[0116] FIG. 11 is an exploded structural schematic diagram of a first wall body, a deformable member and a second insulating member in the battery monomer shown in FIG. 6.

[0117] Explanation of Reference Signs:

[0118] 1000, vehicle;

[0119] 2000, energy storage device;

[0120] 100, battery;

[0121] 10, box body; 11, first part; 12, second part;

[0122] 20、battery cell;

[0123] 21、housing; 211、first wall body; 2111、first connecting surface; 2112、via hole; 2113、first limiting structure; 21131、first limiting part; 2114、second limiting structure; 21141、second limiting part; 2115、first sealing surface; 2116、pressure relief hole; 2117、third connecting surface; 2118、third limiting structure; 21181、third limiting part; 2119、fourth limiting structure; 21191、fourth limiting part; 21120、third sealing surface; 212、cover body; 213、housing body; 2131、second wall body; 2132、third wall body;

[0124] 22、electrode assembly;

[0125] 23、electrode terminal; 231、terminal body; 2311、protruding part; 232、connecting piece;

[0126] 24、first connecting material; 241、first connecting groove;

[0127] 25、deformable piece; 251、second connecting surface; 252、connecting part; 253、deformation part; 254、second sealing surface;

[0128] 26、second connecting material; 261、second connecting groove;

[0129] 27a、pressure relief mechanism; 271a、fourth connecting surface; 272a、fourth sealing surface;

[0130] 27b、protective sheet;

[0131] 28a、first insulating piece; 28b、second insulating piece; 281b、insulating body; 282b、first blocking part; 2821b、first air hole; 283b、second blocking part; 2831b、second air hole;

[0132] 29a、first sealing piece; 29b、second sealing piece;

[0133] 400、battery cabin. DETAILED DESCRIPTION

[0134] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0135] It is to be noted that when a component is referred to as being "fixed" or "set" 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 based on the orientation or positional relationship shown in the drawings, and are only used for convenience of description, and do not 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 used for the purpose of convenience, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0136] 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.

[0137] The battery cell, as the smallest unit constituting the battery, usually includes a shell, an electrode assembly and an electrode terminal. The electrode assembly is placed in the shell, and the electrode terminal is arranged on the wall of the shell. The electrode terminal is electrically connected with the electrode assembly to input or output the electric energy of the battery cell.

[0138] 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 arranged on the battery cell. The deformable member is usually sealingly connected with the shell. In the case of overcharging of the battery cell, the electrode assembly will generate more gas. As the gas increases, the internal pressure of the battery cell increases. In the case that the internal pressure of the battery cell reaches a threshold value, the deformable member will deform under the action of the pressure and move towards the electrode terminal until the deformable member contacts the electrode terminal, so that the electrode terminal is electrically connected with the shell, 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.

[0139] In the related art, the part of the deformable member and the part of the shell are usually heated to melt, and the melted part of the deformable member is combined with the melted part of the shell, so as to realize the connection of the deformable member and the shell. However, in order to improve the volumetric energy density of the battery cell, the shell of the battery cell is arranged to be made of steel material, and in order to enable the deformable member to act in the direction of the electrode terminal when the internal pressure of the battery cell reaches a threshold value, the deformable member is usually made of aluminum material. Since the material of the deformable member and the material of the shell are different, the material properties of the deformable member and the material properties of the shell are also different. After the melted part of the deformable member is combined with the melted part of the shell and solidified, a gap is easily generated at the connection of the deformable member and the shell, so that the internal and external pressure difference of the deformable member cannot be generated in time, the deformable member cannot deform in time and contact the electrode terminal, that is, the charging and discharging circuit of the battery cell cannot be cut off in time, the overcharge phenomenon of the battery cell is further deteriorated, and even thermal runaway is caused, which is not conducive to improving the safety performance of the battery cell.

[0140] In order to improve the safety performance of the battery cell, the battery cell provided by the embodiment of the present application is provided with a first connecting material at the fixed connection between the deformable member and the first wall body. Since the melting point of the first connecting material is lower than the melting point of the material of the deformable member and / or the melting point of the material of the first wall body, when the preset temperature is reached, the first connecting material will melt first. After the first connecting material solidifies, the deformable member and the first wall body are adhered together, so as to realize the fixed connection of the deformable member and the first wall body. Compared with the connection mode of directly combining the melted part of the deformable member with the melted part of the first wall body, the connection reliability of the deformable member and the first wall body is effectively improved, the risk of generating a gap at the connection of the deformable member and the first wall body due to different materials is reduced, the working reliability of the deformable member is effectively improved, the deformable member can act in time in the case of overcharge of the battery cell, the charging and discharging circuit of the battery cell is cut off, and the safety performance of the battery cell is effectively improved.

[0141] The battery cell, the battery, the energy storage device using the battery as a power supply, and the power consumption device are disclosed in the embodiment of the present application. 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, etc., for storing and releasing electric energy. The power consumption device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool, etc.

[0142] Referring to FIG. 2, FIG. 2 is a structural schematic diagram of an energy storage device 2000 provided in an embodiment 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, etc. The energy storage device 2000 can include a battery cabin 400 and a battery 100 disposed in the battery cabin 400, and can further include an electric control module for controlling 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.

[0143] Referring to FIG. 3, FIG. 3 is an exploded schematic diagram of the battery 100 provided in an embodiment of the present application. The battery 100 includes a box body 10 and a battery cell 20, and the battery cell 20 is accommodated in the box body 10. The box body 10 is used to provide an accommodation space for the battery cell 20, and the box body 10 can adopt various structures. In some embodiments, the box body 10 can include a first part 11 and a second part 12, the first part 11 and the second part 12 are overlapped with each other, and the first part 11 and the second part 12 jointly define an accommodation space for accommodating the battery cell 20. The second part 12 can be a hollow structure with one end open, and the first part 11 can be a plate structure, which is arranged on the open side of the second part 12 to jointly define the accommodation space with the second part 12. The first part 11 and the second part 12 can also be hollow structures with one side open, and the open side of the first part 11 is arranged on the open side of the second part 12. Of course, the box body 10 formed by the first part 11 and the second part 12 can have various shapes, such as a cylinder, a cuboid, etc.

[0144] In some embodiments, the box body 10 can be part of the chassis structure of the vehicle 1000. For example, part of the box body 10 can be at least part of the floor of the vehicle 1000, or part of the box body 10 can be at least part of the cross beam and the longitudinal beam of the vehicle 1000.

[0145] In another embodiment, the box body 10 can be part of the support structure of the energy storage device 2000. For example, part of the box body 10 can be at least part of the bracket of the energy storage device 2000.

[0146] Of course, in some embodiments, the battery 100 can not include the box body 10, but a plurality of battery cells 20 are electrically connected and assembled into the energy storage device 2000 or the electric device after being formed into a whole through necessary fixing structures.

[0147] In the battery 100, the battery cells 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 case 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 case 10. The battery 100 can further include other functional components. For example, the battery 100 can further include a busbar for realizing electrical connection between the multiple battery cells 20.

[0148] Each battery cell 20 can be a secondary battery cell or a primary battery cell. The secondary battery cell means a battery cell 20 that can be activated by charging after being discharged, and the primary battery cell means a battery cell 20 that cannot be activated by charging after the electrical energy is consumed. The battery cell 20 can 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 storage 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 other shapes. The prismatic battery cell includes a square battery cell, a blade battery cell, and a multi-prismatic battery cell, such as a hexagonal battery cell. The present application is not particularly limited.

[0149] In order to illustrate the technical solutions provided in the present application, the following will be described in detail in combination with specific drawings and embodiments.

[0150] In a first aspect, in combination with FIGS. 4 to 8, the embodiments of the present application provide a battery cell 20, which includes an electrode assembly 22, an outer shell 21, an electrode terminal 23, a deformable member 25, and a first connecting material 24. The outer shell 21 is configured to accommodate the electrode assembly 22, and the outer shell 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 arranged on the first wall body 211. The deformable member 25 is configured to be deformed to contact the electrode terminal 23, so that the first wall body 211 is electrically connected to the electrode terminal 23. The material of the deformable member 25 is different from the material of the first wall body 211. The deformable member 25 is arranged in fixed connection with the first wall body 211, and the first connecting material 24 is arranged at the fixed connection between the deformable member 25 and the first wall body 211. The melting point of the first connecting material 24 is lower than the melting point of the material of the deformable member 25 and / or the melting point of the material of the first wall body 211.

[0151] 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.

[0152] 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.

[0153] 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.

[0154] 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.

[0155] In some embodiments, the separator can be provided in plural, and can be provided between any adjacent positive electrode sheets or negative electrode sheets.

[0156] 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.

[0157] 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.

[0158] 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.

[0159] 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 of the housing 213 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 are put into the shell, and the cover 212 is covered on the opening of the housing 213 when it is necessary to encapsulate the inside 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 is 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 is not limited to, a cuboid, a cylinder, a hexagonal prism, etc.

[0160] 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 facing 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 to the periphery of the second wall 2131 to define the above-mentioned 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.

[0161] The deformable member 25 is a component for short-circuiting the positive electrode and the negative electrode of the battery monomer 20 in the case of overcharging of the battery monomer 20. In the case of overcharging of the battery monomer 20, the electrode assembly 22 will generate more gas, and as the gas increases, the internal pressure of the battery monomer 20 will also increase. When the internal pressure of the battery monomer 20 reaches a threshold value, the deformable member 25 will deform under the action of the pressure and move towards 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 shell 21, thereby cutting off the charging and discharging circuit of the battery monomer 20.

[0162] The material of the deformable member 25 is different from that of the first wall 211, that is, the deformable member 25 and the first wall 211 are made of different materials, for example, the deformable member 25 is made of aluminum alloy, and the first wall 211 is made of steel; for another example, the deformable member 25 is made of steel, and the first wall 211 is made of aluminum alloy.

[0163] The electrode terminal 23 is a component electrically connected to the electrode assembly 22 for outputting electric energy of the battery cell 20 or inputting electric energy to the battery cell 20. The electrode terminal 23 is provided on the first wall body 211, a 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 another part of the electrode terminal 23 is exposed to the external environment of the battery cell 20 and is connected to a busbar, a sampling device, or the like.

[0164] 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, which can increase the overcurrent area of the electrode terminal 23, thereby improving the overcurrent capacity of the electrode terminal 23.

[0165] 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, such as a circular shape, etc.

[0166] The first connecting material 24 is at least part of the material constituting the fixed connection between the first wall body 211 and the deformable member 25. In some embodiments, the first connecting material 24 constitutes all of the fixed connection between the first wall body 211 and the deformable member 25, in other words, the first connecting material 24 is connected between the first wall body 211 and the deformable member 25. The melting point of the first connecting material 24 is lower than the melting point of the material of the deformable member 25 and / or the melting point of the material of the first wall body 211, which means that when the melting point temperature of the first connecting material 24 is reached, the first connecting material 24 will melt, but the first wall body 211 and / or the deformable member 25 will not melt. As an example, the melting point of the first connecting material 24 is lower than the melting point of the material of the deformable member 25 and the melting point of the material of the first wall body 211. As an example, the melting point of the first connecting material 24 is lower than the melting point of the material of the deformable member 25 and greater than or equal to the melting point of the material of the first wall body 211. As an example, the melting point of the first connecting material 24 is lower than the melting point of the material of the first wall body 211 and greater than or equal to the melting point of the material of the deformable member 25.

[0167] Taking the example that the melting point of the first connecting material 24 is lower than the melting point of the material of the deformable member 25 and the melting point of the material of the first wall body 211, during connection, a heating device is used to heat the first connecting material 24 to the melting point temperature to make the first connecting material 24 melt. Since the melting point of the first connecting material 24 is lower than the melting point of the material of the deformable member 25 and the melting point of the material of the first wall body 211, at this time the deformable member 25 and the first wall body 211 will not melt, and the melted first connecting material 24 is adhered between the deformable member 25 and the first wall body 211, and after the first connecting material 24 cools and solidifies, the first wall body 211 and the deformable member 25 are fixedly connected.

[0168] The battery monomer 20 provided by the embodiments of the present application is fixedly connected with the deformable member 25 and the first wall body 211 by arranging the first connecting material 24 at the fixed connection position of the deformable member 25 and the first wall body 211. Since the melting point of the first connecting material 24 is lower than the melting points of the material of the deformable member 25 and the material of the first wall body 211, the first connecting material 24 melts first when the preset temperature is reached. After the first connecting material 24 solidifies, the deformable member 25 and the first wall body 211 are adhered together, so as to realize the fixed connection of the deformable member 25 and the first wall body 211. Compared with the connection mode of directly combining the melting position of the deformable member 25 and the melting position of the first wall body 211, the connection reliability of the deformable member 25 and the first wall body 211 is effectively improved, the risk of a gap at the connection position of the deformable member 25 and the first wall body 211 caused by different materials is reduced, the working reliability of the deformable member 25 is effectively improved, the deformable member 25 can act in time in the case of overcharging of the battery monomer 20, the charging and discharging circuit of the battery monomer 20 is cut off, and the safety performance of the battery monomer 20 is effectively improved.

[0169] In some embodiments, the first wall body 211 is provided with a through hole 2112 penetrating through opposite sides of the first wall body 211 along the thickness direction. In the case that the internal pressure of the battery monomer 20 reaches a threshold value, the deformable member 25 deforms under the action of the pressure and moves towards the electrode terminal 23 through the through hole 2112 until the deformable member 25 contacts the electrode terminal 23, so as to electrically connect the electrode terminal 23 and the shell 21, thereby cutting off the charging and discharging circuit of the battery monomer 20.

[0170] In some embodiments, the first wall body 211 is provided with an electrode lead-out hole. The electrode terminal 23 includes a terminal body 231 and a connecting piece 232. The terminal body 231 is arranged on the side of the first wall body 211 away from the electrode assembly 22, and is used to connect bus members, sampling devices and other components. The connecting piece 232 is arranged in the electrode lead-out hole and is used to connect the terminal body 231 and the first wall body 211, and is also used to electrically connect the electrode assembly 22, so as to electrically connect the electrode assembly 22 and the terminal body 231. At least part of the terminal body 231 is arranged opposite to the through hole 2112. In the case that the internal pressure of the battery monomer 20 reaches a threshold value, the deformable member 25 deforms under the action of the pressure and moves towards the terminal body 231 through the through hole 2112, so as to make the deformed part 253 contact the terminal body 231. The connecting mode of the connecting piece 232 connecting the first wall body 211 and the terminal body 231 can be riveting, threaded connection and the like, but is not limited thereto.

[0171] Of course, in other embodiments, the electrode terminal 23 can be an integrally formed member. For example, the electrode terminal 23 can have a columnar structure and be fixedly arranged in the electrode lead-out hole.

[0172] In some embodiments, the deformable member 25 can include a connecting portion 252 and a deforming portion 253, the connecting portion 252 is arranged to be fixedly connected with the first wall body 211, in other words, the first connecting material 24 is connected between the first wall body 211 and the connecting portion 252, the connecting portion 252 is arranged around the deforming portion 253 and the through hole 2112. The deforming portion 253 is a part for contacting the electrode terminal 23, the deforming portion 253 is connected to the inner ring side of the connecting portion 252. In the case that the internal pressure of the battery cell 20 reaches a threshold value, the deforming portion 253 will be deformed under the action of the pressure and act towards the direction close to the electrode terminal 23 through the through hole 2112 until the deforming portion 253 contacts the electrode terminal 23, so as to electrically connect the electrode terminal 23 with the shell 21, thereby cutting off the charge-discharge circuit of the battery cell 20.

[0173] For example, the connecting portion 252 and the deforming portion 253 can be an integrally formed member, for example, the deformable member 25 is integrally formed by a stamping process, the outer peripheral portion of the deformable member 25 constitutes the connecting portion 252, and the middle portion of the deformable member 25 constitutes the deforming portion 253.

[0174] For example, the connecting portion 252 and the deforming portion 253 can be integrally connected after being formed respectively, for example, the connecting portion 252 and the deforming portion 253 are welded after being formed respectively.

[0175] In some embodiments of the present application, the first connecting material 24 is a solder.

[0176] The solder can be, but is not limited to, a copper-based solder, a silver-based solder, an aluminum-based solder, a nickel-based solder, a tin-based solder, etc.

[0177] By using the above technical solution, the connection reliability of the deformable member 25 and the first wall body 211 is further improved.

[0178] Of course, in other embodiments, the first connecting material 24 can be a metal material.

[0179] In some embodiments of the present application, referring to FIG. 8, the deformable member 25 cooperates with the first wall body 211 to define a first connecting groove 241, and the first connecting material 24 is accommodated in the first connecting groove 241 and adheres to the inner surface of the first connecting groove 241.

[0180] In some embodiments, the first connecting groove 241 has at least a first groove bottom surface and two first groove side surfaces respectively arranged on opposite sides of the first groove bottom surface, the first groove bottom surface and the two first groove side surfaces define an internal space of the first connecting groove 241, a part of the first connecting material 24 adheres to the first groove bottom surface, another part of the first connecting material 24 adheres to one of the first groove side surfaces, and still another part of the first connecting material 24 adheres to the other of the first groove side surfaces.

[0181] By adopting the above technical solution, not only the position of the first connecting material 24 is effectively limited, but also the adhesion area of the first connecting material 24 is effectively increased, thereby further improving the connection reliability of the deformable part 25 and the first wall body 211.

[0182] In some embodiments of the present application, the first wall body 211 has a first connecting surface 2111, the deformable part 25 has a second connecting surface 251, and the first connecting material 24 is connected between the first connecting surface 2111 and the second connecting surface 251.

[0183] In some embodiments, the first connecting surface 2111 cooperates with the second connecting surface 251 to define the first connecting groove 241.

[0184] For example, the first connecting surface 2111 can constitute a first groove bottom surface and one first groove side surface, and the second connecting surface 251 can constitute another first groove side surface.

[0185] For example, the first connecting surface 2111 can constitute one first groove side surface, and the second connecting surface 251 can constitute a first groove bottom surface and another first groove side surface.

[0186] For example, the first connecting surface 2111 can constitute a part of a first groove bottom surface and one first groove side surface, and the second connecting surface 251 can constitute another part of the first groove bottom surface and another first groove side surface.

[0187] In some embodiments of the present application, the first connecting surface 2111 is a curved surface.

[0188] In some other embodiments of the present application, the second connecting surface 251 is a curved surface.

[0189] In some other embodiments of the present application, the second connecting surface 251 is a curved surface.

[0190] The curved surface can be, but is not limited to, an arc surface, a corner surface, and an irregular surface, etc.

[0191] By adopting the above technical solution, the adhesion area of the first connecting material 24 is effectively increased, thereby further improving the connection reliability of the deformable part 25 and the first wall body 211.

[0192] In some embodiments of the present application, the first connecting surface 2111 is a rough surface.

[0193] In some other embodiments of the present application, the second connecting surface 251 is a rough surface.

[0194] In some other embodiments of the present application, the second connecting surface 251 is a rough surface.

[0195] The rough surface refers to a surface structure composed of a plurality of fine concave-convex bodies, such as a frosted surface. The first connecting surface 2111 and the second connecting surface 251 can be ground into a rough surface by a grinding process, for example, the first connecting surface 2111 and the second connecting surface 251 are ground by a frosted wheel, so that the first connecting surface 2111 and the second connecting surface 251 form a frosted surface.

[0196] By adopting the above technical solution, the adhesion of the first connecting material 24 on the first connecting surface 2111 and the second connecting surface 251 is effectively improved, thereby further improving the connection reliability of the deformable part 25 and the first wall body 211.

[0197] In some embodiments of the present application, the first connecting material 24 is arranged around the deformable part 25.

[0198] In other words, the first connecting material 24 has a ring structure, and correspondingly, the first connecting surface 2111 and the second connecting surface 251 are both annular surfaces, wherein the first connecting surface 2111 is arranged around the deformable part 25, and the second connecting surface 251 is at least part of the peripheral surface of the deformable part 25.

[0199] By adopting the above technical solution, the deformable part 25 and the first wall body 211 can be connected along the circumferential direction of the deformable part 25 by the first connecting material 24, so as to form an annular sealing boundary between the deformable part 25 and the first wall body 211. Not only effectively seal the gap between the deformable part 25 and the first wall body 211, but also make the force on the deformable part 25 more uniform, thereby further improving the connection reliability of the deformable part 25 and the first wall body 211.

[0200] In some embodiments of the present application, referring to FIG. 8, a first limiting structure 2113 is arranged between the first wall body 211 and the deformable part 25, and the first limiting structure 2113 is used to limit the relative position of the first wall body 211 and the deformable part 25 along a direction perpendicular to the thickness direction of the first wall body 211.

[0201] The first limiting structure 2113 is a structure for limiting the relative position of the first wall body 211 and the deformable part 25 along a direction perpendicular to the thickness direction of the first wall body 211, that is, the first wall body 211 and the deformable part 25 are relatively fixed in the direction perpendicular to the thickness direction of the first wall body 211.

[0202] As an example, the above-mentioned first limiting structure 2113 is used to limit the relative position of the first wall body 211 and the deformable part 25 along the width direction of the first wall body 211.

[0203] As an example, the first limiting structure 2113 is configured to limit the relative position of the first wall body 211 and the deformable member 25 along the length direction of the first wall body 211.

[0204] As an example, the first limiting structure 2113 is configured to limit the relative position of the first wall body 211 and the deformable member 25 along the length direction of the first wall body 211.

[0205] The first limiting structure 2113 can be, but is not limited to, a concave-convex matching structure, a bolt structure, etc.

[0206] By adopting the above technical solution, the relative position of the first wall body 211 and the deformable member 25 along the direction perpendicular to the thickness direction of the first wall body 211 is effectively limited, thereby effectively reducing the risk of rupture of the fixed connection between the deformable member 25 and the first wall body 211 due to displacement of the deformable member 25, and further improving the working reliability of the deformable member 25 and the safety performance of the battery cell 20.

[0207] In some embodiments of the present application, referring to FIG. 8, the first limiting structure 2113 includes a first limiting portion 21131, which is arranged on the first wall body 211 and abuts against the deformable member 25 along the direction perpendicular to the thickness direction of the first wall body 211, so as to limit the relative position of the first wall body 211 and the deformable member 25 along the direction perpendicular to the thickness direction of the first wall body 211.

[0208] In some embodiments, the first wall body 211 and the deformable member 25 abut against each other along the thickness direction of the first wall body 211, the first limiting portion 21131 is arranged on the side of the first wall body 211 facing the electrode assembly 22, the first limiting portion 21131 is protrudingly arranged from the first wall body 211 along the thickness direction of the first wall body 211 towards the electrode assembly 22, and the first limiting portion 21131 abuts against one side of the deformable member 25 along the direction perpendicular to the thickness direction of the first wall body 211, so as to limit the relative position of the first wall body 211 and the deformable member 25 along the direction perpendicular to the thickness direction of the first wall body 211.

[0209] In some embodiments, the deformable member 25 can include a connecting portion 252 and a deformed portion 253, the connecting portion 252 is arranged around the deformed portion 253, and the deformed portion 253 is connected to the inner ring side of the connecting portion 252. The first limiting portion 21131 has a ring structure, the first limiting portion 21131 is arranged around the deformable member 25 and abuts against the outer ring side of the connecting portion 252, so as to limit the relative position of the first wall body 211 and the deformable member 25 along the direction perpendicular to the thickness direction of the first wall body 211.

[0210] The first limiting part 21131 and the first wall body 211 can be an integrally formed component. For example, the first limiting part 21131 and the first wall body 211 can be integrally formed by a stamping process. The first limiting part 21131 and the first wall body 211 can also be separately formed and then connected to form an integral whole. For example, the first limiting part 21131 and the first wall body 211 can be welded to form an integral whole.

[0211] By adopting the above technical solution, the first limiting structure 2113 is effectively simplified, and the relative position of the first wall body 211 and the deformable member 25 in a direction perpendicular to the thickness direction of the first wall body 211 is facilitated to be limited.

[0212] In some embodiments of the present application, referring to FIG. 8, the protruding height H1 of the first limiting part 21131 from the first wall body 211 is 0.1 mm-0.6 mm.

[0213] The protruding height H1 of the first limiting part 21131 from the first wall body 211 refers to the dimension of the first limiting part 21131 in the thickness direction of the first wall body 211. The protruding height H1 of the first limiting part 21131 from the first wall body 211 can be selected and set within the above range according to actual application needs, and can be specifically 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, etc.

[0214] By adopting the above technical solution, not only the relative position of the first wall body 211 and the deformable member 25 in a direction perpendicular to the thickness direction of the first wall body 211 is effectively limited, but also the condition that the first limiting part 21131 occupies too much space due to the excessively large protruding height of the first limiting part 21131 is improved, thereby effectively improving the volume energy density of the battery monomer 20.

[0215] In some embodiments of the present application, referring to FIG. 7, the electrode terminal 23 is provided with a protruding part 2311 protruding in a direction close to the deformable member 25 at the via hole 2112, and the deformable member 25 is configured to be deformable to contact the protruding part 2311 through the via hole 2112, so as to electrically connect the first wall body 211 and the electrode terminal 23.

[0216] In some embodiments, the electrode terminal 23 includes a terminal body 231, and a portion of the terminal body 231 opposite the via hole 2112 is protrudingly arranged in a direction close to the deformable member 25 to form the above-mentioned protruding part 2311. At least part of the protruding part 2311 can extend into the via hole 2112 to shorten the distance between the terminal body 231 and the deformable member 25 in the thickness direction of the first wall body 211. The protruding part 2311 can pass through the via hole 2112 or can not pass through the via hole 2112.

[0217] By adopting the technical scheme, the deformable member 25 is in contact with the electrode terminal 23.

[0218] In some embodiments of the present application, referring to FIGS. 7 and 8, the battery cell 20 further comprises a first sealing member 29a arranged between the first wall body 211 and the deformable member 25 to seal the first wall body 211 and the deformable member 25.

[0219] The first sealing member 29a is a component for closing the gap between the first wall body 211 and the deformable member 25. The first sealing member 29a can be made of a flexible material, which can be but is not limited to rubber, silicone, etc. The first wall body 211 and the deformable member 25 press the first sealing member 29a to make the first sealing member 29a compressively deform, thereby closing the gap between the first wall body 211 and the deformable member 25.

[0220] By adopting the technical scheme, the sealing effect of the connection between the first wall body 211 and the deformable member 25 is effectively improved, thereby further improving the working reliability of the deformable member 25 and the safety performance of the battery cell 20.

[0221] In some embodiments of the present application, the first sealing member 29a is arranged around the through hole 2112.

[0222] In some embodiments, the deformable member 25 can comprise a connecting portion 252 and a deforming portion 253, the connecting portion 252 being arranged around the deforming portion 253, and the deforming portion 253 being connected to the inner ring side of the connecting portion 252. The first sealing member 29a is arranged between the connecting portion 252 and the first wall body 211, and the first sealing member 29a is arranged around the through hole 2112.

[0223] For example, the connecting portion 252 and the first sealing member 29a are both in the form of a circular ring, and the connecting portion 252 and the first sealing member 29a are coaxially arranged.

[0224] Of course, in other embodiments, the connecting portion 252 and the first sealing member 29a can also be in the form of a square ring, an elliptical ring, etc.

[0225] By adopting the technical scheme, the communication path between the through hole 2112 and the internal environment of the shell 21 is effectively blocked, the sealing effect of the connection between the first wall body 211 and the deformable member 25 is further improved, thereby further improving the working reliability of the deformable member 25 and the safety performance of the battery cell 20.

[0226] In some embodiments of the present application, referring to FIG. 8, the first wall body 211 and the deformable member 25 clamp the first sealing member 29a along the thickness direction of the first wall body 211, and at least one of the first wall body 211 and the deformable member 25 is provided with a second limiting structure 2114 for limiting the movement of the first sealing member 29a along a direction perpendicular to the thickness direction of the first wall body 211.

[0227] The second limiting structure 2114 is a structure for limiting the movement of the first sealing member 29a along a direction perpendicular to the thickness direction of the first wall body 211. The second limiting structure 2114 can be provided on the first wall body 211, or on the deformable member 25, or part of the second limiting structure 2114 is provided on the first wall body 211 and part of the second limiting structure 2114 is provided on the deformable member 25.

[0228] As an example, the above-mentioned second limiting structure 2114 is used to limit the movement of the first sealing member 29a along the width direction of the first wall body 211.

[0229] As an example, the above-mentioned second limiting structure 2114 is used to limit the movement of the first sealing member 29a along the length direction of the first wall body 211.

[0230] As an example, the above-mentioned second limiting structure 2114 is used to limit the movement of the first sealing member 29a along a direction perpendicular to the thickness direction of the first wall body 211.

[0231] The second limiting structure 2114 can be, but is not limited to, a concave-convex matching structure, a latch structure, etc.

[0232] By adopting the above technical solution, the risk of sealing failure caused by the displacement of the first sealing member 29a along a direction perpendicular to the thickness direction of the first wall body 211 is effectively reduced, the sealing effect of the connection between the first wall body 211 and the deformable member 25 is further improved, the working reliability of the deformable member 25 is further improved, and the safety performance of the battery monomer 20 is further improved.

[0233] In some embodiments of the present application, referring to FIG. 8, the second limiting structure 2114 includes a second limiting portion 21141 provided on the first wall body 211 and abutting against the first sealing member 29a along a direction perpendicular to the thickness direction of the first wall body 211 to limit the movement of the first sealing member 29a along a direction perpendicular to the thickness direction of the first wall body 211.

[0234] In some embodiments, the second limiting portion 21141 is arranged on the side of the first wall body 211 facing the electrode assembly 22, and the second limiting portion 21141 is arranged protruding from the first wall body 211 along the thickness direction of the first wall body 211 towards the electrode assembly 22. The second limiting portion 21141 abuts against one side of the first sealing member 29a along a direction perpendicular to the thickness direction of the first wall body 211, so as to limit the movement of the first sealing member 29a along the direction perpendicular to the thickness direction of the first wall body 211.

[0235] In some embodiments, the first sealing member 29a has a ring structure and surrounds the through hole 2112. The second limiting portion 21141 has a ring structure. The second limiting portion 21141 surrounds the first sealing member 29a and abuts against the outer ring side of the first sealing member 29a, so as to limit the movement of the first sealing member 29a along the direction perpendicular to the thickness direction of the first wall body 211. Alternatively, the second limiting portion 21141 is located on the inner ring side of the first sealing member 29a and abuts against the inner ring side of the first sealing member 29a, so as to limit the movement of the first sealing member 29a along the direction perpendicular to the thickness direction of the first wall body 211.

[0236] The second limiting portion 21141 and the first wall body 211 can be an integrally formed component. For example, the second limiting portion 21141 and the first wall body 211 can be integrally formed by stamping process. Alternatively, the second limiting portion 21141 and the first wall body 211 can be separately formed and then connected to form an integral whole. For example, the second limiting portion 21141 and the first wall body 211 can be welded to form an integral whole.

[0237] By using the above technical solution, the second limiting structure 2114 is effectively simplified, and the position of the first sealing member 29a along the direction perpendicular to the thickness direction of the first wall body 211 is limited.

[0238] In some embodiments of the present application, referring to FIG. 8, the protruding height H2 of the second limiting portion 21141 from the first wall body 211 is 0.1 mm-0.6 mm.

[0239] The protruding height H2 of the second limiting portion 21141 from the first wall body 211 refers to the dimension of the second limiting portion 21141 along the thickness direction of the first wall body 211. The protruding height H2 of the second limiting portion 21141 from the first wall body 211 can be selected and set within the above range according to actual application needs, and can be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, etc.

[0240] By adopting the technical scheme, not only the position of the first sealing member 29a is effectively limited, but also the case that the second limiting portion 21141 occupies too much space due to the too large protruding height of the second limiting portion 21141 is improved, thereby effectively improving the volume energy density of the battery monomer 20.

[0241] Of course, in other embodiments, the second limiting portion 21141 can be arranged on the deformable member 25, for example, the second limiting portion 21141 is arranged on the side of the connecting portion 252 of the deformable member 25 away from the electrode assembly 22.

[0242] In some embodiments of the present application, referring to FIG. 8, the first wall body 211 has a first sealing surface 2115, and the deformable member 25 has a second sealing surface 254, the first sealing surface 2115 and the second sealing surface 254 cooperate to clamp the first sealing member 29a, and the compression rate of the first sealing member 29a in the direction from the first sealing surface 2115 to the second sealing surface 254 is 2%-50%.

[0243] In some embodiments, the first sealing surface 2115 and the second sealing surface 254 are arranged opposite along the thickness direction of the first wall body 211, in other words, the first sealing surface 2115 and the second sealing surface 254 cooperate to clamp the first sealing member 29a along the thickness direction of the first wall body 211, that is, the direction from the first sealing surface 2115 to the second sealing surface 254 refers to the thickness direction of the first wall body 211.

[0244] The compression rate of the first sealing member 29a refers to the ratio of the size L1 of the first sealing member 29a after being compressed to the original size of the first sealing member 29a, it should be noted that the size L1 of the first sealing member 29a after being compressed refers to the size of the first sealing member 29a in the direction from the first sealing surface 2115 to the second sealing surface 254 after being extruded by the first wall body 211 and the deformable member 25, and the original size of the first sealing member 29a refers to the size of the first sealing member 29a in the direction from the first sealing surface 2115 to the second sealing surface 254 before being assembled between the first wall body 211 and the deformable member 25.

[0245] By adopting the technical scheme, not only the sealing effect of the connection between the first wall body 211 and the deformable member 25 is effectively improved, but also the risk of rupture of the first sealing member 29a due to excessive pressure is reduced, thereby effectively improving the reliability of the first sealing member 29a.

[0246] In some embodiments of the present application, referring to FIG. 6, the battery monomer 20 includes two deformable members 25 and two electrode terminals 23 with opposite polarities, the two electrode terminals 23 are arranged to be insulated from the first wall body 211, and the two electrode terminals 23 are arranged in one-to-one correspondence with the two deformable members 25.

[0247] It can be understood that one of the electrode terminals 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.

[0248] The two electrode terminals 23 are insulated from the first wall body 211, which means that insulating structures are arranged between the two electrode terminals 23 and the first wall body 211, and the two insulating structures insulate and separate the two electrode terminals 23 from the first wall body 211.

[0249] The one-to-one correspondence between the two electrode terminals 23 and the two deformable members 25 means that, when the internal pressure of the battery monomer 20 reaches a threshold value, one of the deformable members 25 deforms under the pressure and moves towards the direction of approaching one of the electrode terminals 23, and the other deformable member 25 deforms under the pressure and moves towards the direction of approaching the other electrode terminal 23, until the two deformable members 25 are in one-to-one contact 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 charging and discharging circuit of the battery monomer 20.

[0250] By adopting the above technical solution, the safety performance of the battery monomer 20 is further improved.

[0251] Of course, in other embodiments, the positive electrode terminal can be insulated from the shell 21, and the negative electrode terminal can be electrically connected with the shell 21, that is, the entire shell 21 can be used as the negative electrode of the battery monomer 20, and the number of deformable members 25 is one, and in the case that the internal pressure of the battery monomer 20 reaches a threshold value, the deformable member 25 moves towards the direction of approaching the positive electrode terminal under the action of the pressure, until the deformable member 25 is in contact with the positive electrode terminal, at this time, the positive electrode and the negative electrode of the battery monomer 20 are short-circuited, thereby cutting off the charging and discharging circuit of the battery monomer 20.

[0252] It can also be that the negative electrode terminal is insulated from the shell 21, and the positive electrode terminal is electrically connected with the shell 21, that is, the entire shell 21 can be used as the positive electrode of the battery monomer 20, and the number of deformable members 25 is one, and in the case that the internal pressure of the battery monomer 20 reaches a threshold value, the deformable member 25 moves towards the direction of approaching the negative electrode terminal under the action of the pressure, until the deformable member 25 is in contact with the negative electrode terminal, at this time, the positive electrode and the negative electrode of the battery monomer 20 are short-circuited, thereby cutting off the charging and discharging circuit of the battery monomer 20.

[0253] In some embodiments of the present application, referring to FIGS. 7 and 8, the battery monomer 20 further comprises a first insulating member 28a arranged between the electrode terminal 23 and the first wall body 211 to insulate the electrode terminal 23 from the first wall body 211.

[0254] The first insulating member 28a 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 first insulating member 28a is located between the electrode terminal 23 and the first wall body 211, and is used to insulate and separate the electrode terminal 23 from the first wall body 211, thereby reducing the risk of short circuit.

[0255] By adopting the above technical solution, the electrode terminal 23 and the first wall body 211 can be easily insulated and separated.

[0256] In some embodiments of the present application, referring to FIGS. 9 and 10, the first wall body 211 is provided with a pressure relief hole 2116, which penetrates through the opposite sides of the first wall body 211 along the thickness direction. The battery monomer 20 further comprises a pressure relief mechanism 27a, which is arranged on the pressure relief hole 2116. The material of the pressure relief mechanism 27a is different from that of the first wall body 211. The pressure relief mechanism 27a is fixedly connected with the first wall body 211, and the second connecting material 26 is arranged at the fixed connection position of the pressure relief mechanism 27a and the first wall body 211. The melting point of the second connecting material 26 is lower than that of the material of the pressure relief mechanism 27a and / or that of the material of the first wall body 211.

[0257] The second connecting material 26 is at least part of the material constituting the fixed connection position of the first wall body 211 and the pressure relief mechanism 27a. In some embodiments, the second connecting material 26 constitutes the entire fixed connection position of the first wall body 211 and the pressure relief mechanism 27a, that is, the second connecting material 26 is connected between the first wall body 211 and the pressure relief mechanism 27a. The melting point of the second connecting material 26 is lower than that of the material of the pressure relief mechanism 27a and / or that of the material of the first wall body 211, which means that the second connecting material 26 will melt when the melting point temperature is reached, but the first wall body 211 and / or the pressure relief mechanism 27a will not melt. As an example, the melting point of the second connecting material 26 is lower than that of the material of the pressure relief mechanism 27a and that of the material of the first wall body 211. As an example, the melting point of the second connecting material 26 is lower than that of the material of the pressure relief mechanism 27a and greater than or equal to that of the material of the first wall body 211. As an example, the melting point of the second connecting material 26 is lower than that of the material of the first wall body 211 and greater than or equal to that of the material of the pressure relief mechanism 27a.

[0258] For example, the melting point of the second connecting material 26 is lower than the melting points of the material of the pressure relief mechanism 27a and the material of the first wall body 211. During connection, the second connecting material 26 is heated to the melting point by a heating device, so that the second connecting material 26 is melted. Since the melting point of the second connecting material 26 is lower than the melting points of the material of the pressure relief mechanism 27a and the material of the first wall body 211, the pressure relief mechanism 27a and the first wall body 211 are not dissolved at this time. The melted second connecting material 26 is adhered between the pressure relief mechanism 27a and the first wall body 211. After the second connecting material 26 is cooled and solidified, the first wall body 211 and the pressure relief mechanism 27a are fixedly connected.

[0259] The pressure relief mechanism 27a is a mechanism for releasing the internal pressure when the internal pressure or temperature of the battery monomer 20 reaches a threshold value. The pressure relief mechanism 27a is arranged on the pressure relief hole 2116 to close the pressure relief hole 2116, so as to isolate the internal environment of the battery monomer 20 from the external environment of the battery monomer 20. In the case where the internal pressure or temperature of the battery monomer 20 reaches the threshold value, the pressure relief mechanism 27a is broken under the action of pressure, so that the internal environment of the battery monomer 20 and the external environment of the battery monomer 20 are communicated through the pressure relief hole 2116. High-temperature gas can be discharged to the external environment of the battery monomer 20 through the pressure relief hole 2116.

[0260] The material of the pressure relief mechanism 27a is different from the material of the first wall body 211, that is, the pressure relief mechanism 27a and the first wall body 211 are made of different materials. For example, the pressure relief mechanism 27a is made of aluminum alloy, and the first wall body 211 is made of steel. For another example, the pressure relief mechanism 27a is made of steel, and the first wall body 211 is made of aluminum alloy.

[0261] In some embodiments, the number of electrode terminals 23 is two, and the pressure relief hole 2116 can be arranged between the two electrode terminals 23.

[0262] By adopting the above technical solution, the connection reliability of the pressure relief mechanism 27a and the first wall body 211 is effectively improved, and the risk of a gap being generated at the connection between the pressure relief mechanism 27a and the first wall body 211 due to different materials is reduced, thereby effectively improving the working reliability of the pressure relief mechanism 27a, and further effectively improving the safety performance of the battery monomer 20.

[0263] In some embodiments of the present application, the second connecting material 26 is a brazing material.

[0264] The brazing material can be, but is not limited to, a copper-based brazing material, a silver-based brazing material, an aluminum-based brazing material, a nickel-based brazing material, a tin-based brazing material, etc.

[0265] By adopting the above technical solution, the connection reliability of the pressure relief mechanism 27a and the first wall body 211 is further improved.

[0266] Of course, in other embodiments, the second connecting material 26 can be metal.

[0267] In some embodiments of the present application, referring to FIG. 10, the pressure relief mechanism 27a cooperates with the first wall body 211 to define a second connecting groove 261, and the second connecting material 26 is accommodated in the second connecting groove 261 and adheres to the inner surface of the second connecting groove 261.

[0268] In some embodiments, the second connecting groove 261 has at least a second groove bottom surface and two second groove side surfaces respectively arranged on opposite sides of the second groove bottom surface, the second groove bottom surface and the two second groove side surfaces define an internal space of the second connecting groove 261, a portion of the second connecting material 26 adheres to the second groove bottom surface, another portion of the second connecting material 26 adheres to one of the second groove side surfaces, and still another portion of the second connecting material 26 adheres to the other of the second groove side surfaces.

[0269] By adopting the above technical solutions, not only the position of the second connecting material 26 is effectively limited, but also the adhesion area of the second connecting material 26 is effectively increased, thereby further improving the connection reliability of the pressure relief mechanism 27a and the first wall body 211.

[0270] In some embodiments of the present application, the first wall body 211 has a third connecting surface 2117, the pressure relief mechanism 27a has a fourth connecting surface 271a, and the second connecting material 26 is connected between the third connecting surface 2117 and the fourth connecting surface 271a.

[0271] In some embodiments, the third connecting surface 2117 cooperates with the fourth connecting surface 271a to define the above-mentioned second connecting groove 261.

[0272] For example, the third connecting surface 2117 can constitute the second groove bottom surface and one of the second groove side surfaces, and the fourth connecting surface 271a can constitute the other of the second groove side surfaces.

[0273] For example, the third connecting surface 2117 can constitute one of the second groove side surfaces, and the fourth connecting surface 271a can constitute the second groove bottom surface and the other of the second groove side surfaces.

[0274] For example, the third connecting surface 2117 can constitute a portion of the second groove bottom surface and one of the second groove side surfaces, and the fourth connecting surface 271a can constitute another portion of the second groove bottom surface and the other of the second groove side surfaces.

[0275] In some embodiments of the present application, the third connecting surface 2117 is a curved surface.

[0276] In some other embodiments of the present application, the fourth connecting surface 271a is a curved surface.

[0277] In some embodiments of the present application, the third connecting surface 2117 is a rough surface.

[0278] The curved surface can be, but is not limited to, an arc surface, a beveled surface, and an irregular surface, etc.

[0279] By adopting the above technical solution, the adhesion area of the second connecting material 26 is effectively increased, thereby further improving the connection reliability of the pressure relief mechanism 27a and the first wall body 211.

[0280] In some embodiments of the present application, the third connecting surface 2117 is a rough surface.

[0281] In some other embodiments of the present application, the fourth connecting surface 271a is a rough surface.

[0282] In some other embodiments of the present application, the third connecting surface 2117 and the fourth connecting surface 271a are both rough surfaces.

[0283] The rough surface refers to a surface structure composed of a plurality of fine concave-convex bodies, such as a frosted surface. The third connecting surface 2117 and the fourth connecting surface 271a can be polished into a rough surface by a polishing process, for example, the third connecting surface 2117 and the fourth connecting surface 271a are polished by a frosted wheel to form a frosted surface.

[0284] By adopting the above technical solution, the adhesion of the second connecting material 26 on the third connecting surface 2117 and the fourth connecting surface 271a is effectively improved, thereby further improving the connection reliability of the pressure relief mechanism 27a and the first wall body 211.

[0285] In some embodiments of the present application, the second connecting material 26 is arranged around the pressure relief mechanism 27a.

[0286] In other words, the second connecting material 26 has a ring structure, and correspondingly, the third connecting surface 2117 and the fourth connecting surface 271a are both annular surfaces, wherein the third connecting surface 2117 is arranged around the pressure relief mechanism 27a, and the fourth connecting surface 271a is at least part of the outer peripheral surface of the pressure relief mechanism 27a.

[0287] By adopting the above technical solution, the pressure relief mechanism 27a and the first wall body 211 can be connected by the second connecting material 26 along the circumferential direction of the pressure relief mechanism 27a, so as to form a ring-shaped sealing boundary between the pressure relief mechanism 27a and the first wall body 211, not only effectively sealing the gap between the pressure relief mechanism 27a and the first wall body 211, but also making the stress of the pressure relief mechanism 27a more uniform, thereby further improving the connection reliability of the pressure relief mechanism 27a and the first wall body 211.

[0288] In some embodiments of the present application, referring to FIG. 10, a third limiting structure 2118 is arranged between the first wall body 211 and the pressure relief mechanism 27a, and is configured to limit the relative position of the first wall body 211 and the pressure relief mechanism 27a in a direction perpendicular to the thickness direction of the first wall body 211.

[0289] The third limiting structure 2118 is configured to limit the relative position of the first wall body 211 and the pressure relief mechanism 27a in a direction perpendicular to the thickness direction of the first wall body 211, i.e., the first wall body 211 and the pressure relief mechanism 27a are relatively fixed in the direction perpendicular to the thickness direction of the first wall body 211.

[0290] For example, the third limiting structure 2118 is configured to limit the relative position of the first wall body 211 and the pressure relief mechanism 27a in the width direction of the first wall body 211.

[0291] For example, the third limiting structure 2118 is configured to limit the relative position of the first wall body 211 and the pressure relief mechanism 27a in the length direction of the first wall body 211.

[0292] For example, the third limiting structure 2118 is configured to limit the relative position of the first wall body 211 and the pressure relief mechanism 27a in any direction perpendicular to the thickness direction of the first wall body 211.

[0293] The third limiting structure 2118 can be, but is not limited to, a concave-convex matching structure, a bolt structure, etc.

[0294] By adopting the above technical solution, the relative position of the first wall body 211 and the pressure relief mechanism 27a in a direction perpendicular to the thickness direction of the first wall body 211 is effectively limited, thereby effectively reducing the risk of rupture of the fixed connection between the pressure relief mechanism 27a and the first wall body 211 due to displacement of the pressure relief mechanism 27a, and further improving the working reliability of the pressure relief mechanism 27a and the safety performance of the battery monomer 20.

[0295] In some embodiments of the present application, referring to FIG. 10, the third limiting structure 2118 includes a third limiting portion 21181 arranged on the first wall body 211 and abutting against the pressure relief mechanism 27a in a direction perpendicular to the thickness direction of the first wall body 211, so as to limit the relative position of the first wall body 211 and the pressure relief mechanism 27a in a direction perpendicular to the thickness direction of the first wall body 211.

[0296] In some embodiments, the first wall body 211 and the pressure relief mechanism 27a abut each other along the thickness direction of the first wall body 211, the third limiting portion 21181 is arranged on the side of the first wall body 211 facing the electrode assembly 22, the third limiting portion 21181 is arranged protruding from the first wall body 211 along the thickness direction of the first wall body 211 towards the direction close to the electrode assembly 22, and the third limiting portion 21181 abuts against the side of the pressure relief mechanism 27a along the direction perpendicular to the thickness direction of the first wall body 211 to limit the relative position of the first wall body 211 and the pressure relief mechanism 27a along the direction perpendicular to the thickness direction of the first wall body 211.

[0297] In some embodiments, the third limiting portion 21181 has a ring structure, the third limiting portion 21181 is arranged around the pressure relief mechanism 27a and abuts against the outer circumferential side of the pressure relief mechanism 27a to limit the relative position of the first wall body 211 and the pressure relief mechanism 27a along the direction perpendicular to the thickness direction of the first wall body 211.

[0298] The third limiting portion 21181 and the first wall body 211 can be an integrally formed member, for example, the third limiting portion 21181 and the first wall body 211 can be integrally formed by a stamping process. The third limiting portion 21181 and the first wall body 211 can also be separately formed and then connected into one whole, for example, the third limiting portion 21181 and the first wall body 211 can be welded into one whole.

[0299] By adopting the above technical solution, the third limiting structure 2118 is effectively simplified, and the relative position of the first wall body 211 and the pressure relief mechanism 27a along the direction perpendicular to the thickness direction of the first wall body 211 is facilitated to be limited.

[0300] In some embodiments of the present application, referring to FIG. 10, the protruding height H3 of the third limiting portion 21181 from the first wall body 211 is 0.1 mm-0.6 mm.

[0301] The protruding height H3 of the third limiting portion 21181 from the first wall body 211 refers to the dimension of the third limiting portion 21181 along the thickness direction of the first wall body 211. The protruding height H3 of the third limiting portion 21181 from the first wall body 211 can be selected and set within the above range according to actual application needs, and can be specifically 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, etc.

[0302] By adopting the above technical solution, not only the relative position of the first wall body 211 and the pressure relief mechanism 27a along the direction perpendicular to the thickness direction of the first wall body 211 is effectively limited, but also the condition that the third limiting portion 21181 occupies too much space due to the too large protruding height of the third limiting portion 21181 is improved, thereby effectively improving the volume energy density of the battery monomer 20.

[0303] In some embodiments of the present application, referring to FIGS. 9 and 10, the battery cell 20 further comprises a second sealing member 29b disposed between the first wall body 211 and the pressure relief mechanism 27a to seal the connection between the first wall body 211 and the pressure relief mechanism 27a.

[0304] The second sealing member 29b is a component for closing the gap between the first wall body 211 and the pressure relief mechanism 27a. The second sealing member 29b can be made of a flexible material, which can be but is not limited to rubber, silicone, etc. The first wall body 211 and the pressure relief mechanism 27a press the second sealing member 29b to compress and deform the second sealing member 29b, thereby closing the gap between the first wall body 211 and the pressure relief mechanism 27a.

[0305] By adopting the above technical solution, the sealing effect of the connection between the first wall body 211 and the pressure relief mechanism 27a is effectively improved, thereby further improving the working reliability of the pressure relief mechanism 27a and further improving the safety performance of the battery cell 20.

[0306] In some embodiments of the present application, the second sealing member 29b is disposed around the pressure relief hole 2116.

[0307] It can be understood that the second sealing member 29b has a ring structure, and the shape of the second sealing member 29b is adapted to the shape of the pressure relief hole 2116, for example, the pressure relief hole 2116 has an oval shape, and the second sealing member 29b has an oval ring structure.

[0308] By adopting the above technical solution, the communication path between the pressure relief hole 2116 and the internal environment of the shell 21 is effectively blocked, the sealing effect of the connection between the first wall body 211 and the pressure relief mechanism 27a is further improved, thereby further improving the working reliability of the pressure relief mechanism 27a and further improving the safety performance of the battery cell 20.

[0309] In some embodiments of the present application, referring to FIG. 10, the first wall body 211 and the pressure relief mechanism 27a clamp the second sealing member 29b along the thickness direction of the first wall body 211, and at least one of the first wall body 211 and the pressure relief mechanism 27a is provided with a fourth limiting structure 2119 for limiting the movement of the second sealing member 29b along a direction perpendicular to the thickness direction of the first wall body 211.

[0310] The fourth limiting structure 2119 is a structure for limiting the movement of the second sealing member 29b in a direction perpendicular to the thickness direction of the first wall body 211. The fourth limiting structure 2119 can be provided on the first wall body 211, or on the pressure relief mechanism 27a, or a part of the fourth limiting structure 2119 can be provided on the first wall body 211 and another part of the fourth limiting structure 2119 can be provided on the pressure relief mechanism 27a.

[0311] As an example, the fourth limiting structure 2119 described above is used to limit the movement of the second sealing member 29b in the width direction of the first wall body 211.

[0312] As an example, the fourth limiting structure 2119 described above is used to limit the movement of the second sealing member 29b in the length direction of the first wall body 211.

[0313] As an example, the fourth limiting structure 2119 described above is used to limit the movement of the second sealing member 29b in a planar direction perpendicular to the thickness direction of the first wall body 211.

[0314] The fourth limiting structure 2119 can be, but is not limited to, a concave-convex matching structure, a bolt structure, etc.

[0315] By adopting the technical solution described above, the risk of seal failure caused by the displacement of the second sealing member 29b in a direction perpendicular to the thickness direction of the first wall body 211 is effectively reduced, the sealing effect of the connection between the first wall body 211 and the pressure relief mechanism 27a is further improved, the working reliability of the pressure relief mechanism 27a is further improved, and the safety performance of the battery monomer 20 is further improved.

[0316] In some embodiments of the present application, referring to FIG. 10, the fourth limiting structure 2119 includes a fourth limiting portion 21191, which is provided on the first wall body 211 and abuts against the second sealing member 29b in a direction perpendicular to the thickness direction of the first wall body 211 to limit the movement of the second sealing member 29b in the direction perpendicular to the thickness direction of the first wall body 211.

[0317] In some embodiments, the fourth limiting portion 21191 is provided on the side of the first wall body 211 facing the electrode assembly 22, the fourth limiting portion 21191 is protrudingly provided from the first wall body 211 in the thickness direction of the first wall body 211 towards the electrode assembly 22, and the fourth limiting portion 21191 abuts against one side of the second sealing member 29b in a direction perpendicular to the thickness direction of the first wall body 211 to limit the movement of the second sealing member 29b in the direction perpendicular to the thickness direction of the first wall body 211.

[0318] In some embodiments, the second seal 29b is in a ring structure and surrounds the pressure relief hole 2116. The fourth limiting portion 21191 is in a ring structure. The fourth limiting portion 21191 surrounds the second seal 29b and abuts the outer ring side of the second seal 29b to limit the movement of the second seal 29b in a direction perpendicular to the thickness direction of the first wall body 211, or the fourth limiting portion 21191 is located at the inner ring side of the second seal 29b and abuts the inner ring side of the second seal 29b to limit the movement of the second seal 29b in a direction perpendicular to the thickness direction of the first wall body 211.

[0319] The fourth limiting portion 21191 and the first wall body 211 can be an integrally formed component, for example, the fourth limiting portion 21191 and the first wall body 211 can be integrally formed by a stamping process. The fourth limiting portion 21191 and the first wall body 211 can also be separately formed and then connected to form a whole, for example, the fourth limiting portion 21191 and the first wall body 211 can be welded to form a whole.

[0320] By adopting the above technical solution, the fourth limiting structure 2119 is effectively simplified, and the position of the second seal 29b in a direction perpendicular to the thickness direction of the first wall body 211 is facilitated to be limited.

[0321] In some embodiments of the present application, referring to FIG. 10, the protruding height H4 of the fourth limiting portion 21191 from the first wall body 211 is 0.1mm-0.6mm.

[0322] The protruding height H4 of the fourth limiting portion 21191 from the first wall body 211 refers to the dimension of the fourth limiting portion 21191 in the thickness direction of the first wall body 211. The protruding height H4 of the fourth limiting portion 21191 from the first wall body 211 can be selected and set within the above range according to actual application needs, and can be specifically 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, etc.

[0323] By adopting the above technical solution, not only the position of the second seal 29b is effectively limited, but also the condition that the fourth limiting portion 21191 occupies too much space due to the protruding height of the fourth limiting portion 21191 being too large is improved, thereby effectively improving the volume energy density of the battery monomer 20.

[0324] Of course, in other embodiments, the fourth limiting portion 21191 can be arranged on the pressure relief mechanism 27a, for example, the fourth limiting portion 21191 is arranged on the side of the pressure relief mechanism 27a facing away from the electrode assembly 22.

[0325] In some embodiments of the present application, referring to FIG. 10, the first wall body 211 has a third sealing surface 21120, the pressure relief mechanism 27a has a fourth sealing surface 272a, the third sealing surface 21120 and the fourth sealing surface 272a clamp the second sealing member 29b together, and the compression rate of the second sealing member 29b in the direction from the third sealing surface 21120 to the fourth sealing surface 272a is 2%-50%.

[0326] In some embodiments, the third sealing surface 21120 and the fourth sealing surface 272a are arranged opposite along the thickness direction of the first wall body 211, that is, the third sealing surface 21120 and the fourth sealing surface 272a clamp the second sealing member 29b together along the thickness direction of the first wall body 211, and the direction from the third sealing surface 21120 to the fourth sealing surface 272a refers to the thickness direction of the first wall body 211.

[0327] The compression rate of the second sealing member 29b refers to the ratio of the compressed size L2 of the second sealing member 29b to the original size of the second sealing member 29b, and it should be noted that the compressed size L2 of the second sealing member 29b refers to the size of the second sealing member 29b in the direction from the third sealing surface 21120 to the fourth sealing surface 272a after the second sealing member 29b is compressed by the first wall body 211 and the pressure relief mechanism 27a, 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 21120 to the fourth sealing surface 272a before the second sealing member 29b is assembled between the first wall body 211 and the pressure relief mechanism 27a.

[0328] By adopting the above technical solutions, not only the sealing effect of the connection between the first wall body 211 and the pressure relief mechanism 27a is effectively improved, but also the risk of the second sealing member 29b being broken due to excessive pressure is reduced, and the reliability of the second sealing member 29b is effectively improved.

[0329] In some embodiments of the present application, the pressure relief mechanism 27a is made of aluminum alloy.

[0330] In other words, the pressure relief mechanism 27a is made of aluminum alloy.

[0331] By adopting the above technical solutions, the pressure relief mechanism 27a is facilitated to be opened and release the internal pressure of the battery monomer 20 when the internal pressure of the battery monomer 20 reaches the threshold value, thereby further improving the safety performance of the battery monomer 20.

[0332] In some embodiments of the present application, referring to FIG. 9 and FIG. 10, the battery monomer 20 further comprises a protective sheet 27b, the protective sheet 27b is arranged on the side of the first wall body 211 away from the electrode assembly 22 and covers the pressure relief hole 2116, and the pressure relief mechanism 27a is arranged on the side of the first wall body 211 facing the electrode assembly 22.

[0333] The protective sheet 27b is a component for closing the external port of the pressure relief hole 2116 to block foreign matters from entering the pressure relief hole 2116. The protective sheet 27b can be a film or a plate. The material of the protective sheet can be, but is not limited to, polyimide, polyvinyl chloride, polyester, polyurethane, etc.

[0334] By adopting the above technical solution, foreign matters such as electrolyte and dust can be blocked from entering the pressure relief hole 2116, reducing the adverse effects of foreign matters on the pressure relief mechanism 27a, thereby further improving the safety performance of the battery monomer 20.

[0335] In some embodiments of the present application, the protective sheet 27b is bonded to the first wall body 211.

[0336] In some embodiments, an adhesive layer can be provided on the protective sheet 27b, and the protective sheet 27b is bonded to the first wall body 211 through the adhesive layer.

[0337] In other embodiments, an adhesive can be coated on the first wall body 211, and the protective sheet 27b is bonded to the first wall body 211 through the adhesive.

[0338] By adopting the above technical solution, the protective sheet 27b is fixed on the first wall body 211.

[0339] In some embodiments of the present application, referring to FIG. 6, the cover 212 constitutes the first wall body 211, the first wall body 211 is connected to the shell 213, and the material of the first wall body 211 is the same as that of the shell 213.

[0340] The material of the first wall body 211 is the same as that of the shell 213 means that 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 both made of steel, and for example, the shell 213 and the first wall body 211 are both made of aluminum alloy.

[0341] 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 are also the same as those of the shell 213, 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 and air pressure, 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 between the first wall body 211 and the shell 213, and further improving the safety performance of the battery monomer 20.

[0342] In some embodiments of the present application, the shell 213 is welded to the first wall body 211.

[0343] The welding of the shell 213 and the first wall body 211 refers to that, 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 part of the shell 213 and the melted part of the first wall body 211 are combined with each other, and after the melted part of the shell 213 and the melted part of the first wall body 211 are solidified, the shell 213 and the first wall body 211 are connected.

[0344] The welding mode of the shell 213 and the first wall body 211 can be, but is not limited to, laser welding, electric arc welding, ultrasonic welding and the like.

[0345] 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 in the welding process, thereby further improving the connection reliability of the first wall body 211 and the shell 213.

[0346] In some embodiments of the present application, the deformable member 25 is an aluminum member, and the first wall body 211 is a steel member.

[0347] In other words, the deformable member 25 is made of aluminum alloy, and the first wall body 211 is made of steel.

[0348] In the case of equal volume, the weight of the aluminum alloy member is less than that of the steel member, and the hardness of the steel member is greater than that of the aluminum alloy member. By adopting the above technical solution, not only the connection reliability of the deformable member 25 and the first wall body 211 is improved, but also the structural strength of the first wall body 211 is improved.

[0349] In some embodiments of the present application, referring to FIG. 11, the battery monomer 20 further includes a second insulating member 28b arranged on the side of the first wall body 211 facing the electrode assembly 22, the second insulating member 28b includes an insulating body 281b and a first blocking portion 282b connected to the insulating body 281b, and the first blocking portion 282b is arranged opposite to the deformable member 25.

[0350] The second insulating member 28b refers to a component made of insulating material, which can be, but is not limited to, polyester, epoxy, polyurethane, polybutadiene acid, organic silicon, polyester imine and polyimide, etc. The second insulating member 28b 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 deformable member 25, the pressure relief mechanism 27a and other components from the electrode assembly 22, thereby reducing the risk of short circuit.

[0351] The insulation main body 281b is a main part of the second insulation member 28b, and is used to insulate and separate the first wall body 211 and the electrode assembly 22. The first blocking part 282b is connected to a part of the insulation main body 281b opposite to the deformable member 25, and is used to protect the deformable member 25 and insulate and separate the deformable member 25 and the electrode assembly 22. The first blocking part 282b and the insulation main body 281b can be an integrally formed member, for example, the first blocking part 282b and the insulation main body 281b are integrally formed by injection molding, or the first blocking part 282b and the insulation main body 281b are separately formed and then connected to each other to form an integral whole, for example, the first blocking part 282b and the insulation main body 281b are bonded.

[0352] By adopting the above technical solution, the deformable member 25 is effectively protected, and the risk of damage of the deformable member 25 caused by interference with other components in the battery monomer 20 is effectively reduced.

[0353] In some embodiments of the present application, referring to FIG. 11, the first blocking part 282b is provided with a first gas hole 2821b, and the first gas hole 2821b is used for gas to flow from the electrode assembly 22 to the deformable member 25.

[0354] The first gas hole 2821b penetrates through the first blocking part 282b, so that the gas generated by the electrode assembly 22 can enter the inside of the first blocking part 282b and flow to the deformable member 25. The number of the first gas hole 2821b can be one or multiple. When the number of the first gas hole 2821b is multiple, the multiple first gas holes 2821b can be uniformly distributed on the first blocking part 282b.

[0355] In some embodiments, the inside of the first blocking part 282b forms a first cavity, and at least part of the deformable member 25 is accommodated in the first cavity. The first cavity and the cavity of the shell 213 are connected through the first gas hole 2821b, so that the gas generated by the electrode assembly 22 can enter the first cavity and flow to.

[0356] By adopting the above technical solution, in the case of overcharging of the battery monomer 20, the gas generated by the electrode assembly 22 can reach the deformable member 25 through the first gas hole 2821b 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 monomer 20, and further improving the safety performance of the battery monomer 20.

[0357] In some embodiments of the present application, referring to FIG. 11, the second insulation member 28b further comprises a second blocking portion 283b connected to the insulation body 281b, the second blocking portion 283b is arranged opposite to the pressure relief mechanism 27a, and the second blocking portion 283b is provided with a second gas hole 2831b for allowing the gas generated by the electrode assembly 22 to flow to the pressure relief mechanism 27a.

[0358] The second blocking portion 283b is connected to the part of the insulation body 281b opposite to the pressure relief mechanism 27a, and functions to protect the pressure relief mechanism 27a and to insulate and separate the pressure relief mechanism 27a from the electrode assembly 22. The first blocking portion 282b, the second blocking portion 283b and the insulation body 281b can be an integrally formed member, for example, the first blocking portion 282b, the second blocking portion 283b and the insulation body 281b are integrally formed by injection molding, or the first blocking portion 282b and the second blocking portion 283b are respectively formed and then connected to form an integral whole, for example, the first blocking portion 282b and the second blocking portion 283b are respectively bonded to the insulation body 281b.

[0359] The second gas hole 2831b penetrates through the second blocking portion 283b, so that the gas generated by the electrode assembly 22 can enter the inside of the second blocking portion 283b and flow to the pressure relief mechanism 27a, and the number of the second gas hole 2831b can be one or multiple, and when the number of the second gas hole 2831b is multiple, the multiple second gas holes 2831b can be uniformly distributed on the second blocking portion 283b.

[0360] In some embodiments, the inside of the second blocking portion 283b forms a second cavity, at least part of the pressure relief mechanism 27a is accommodated in the second cavity, and the second cavity is connected to the cavity of the shell 213 through the second gas hole 2831b, so that the gas generated by the electrode assembly 22 can enter the second cavity and flow to the pressure relief mechanism 27a.

[0361] By using the above technical solution, the protection of the pressure relief mechanism 27a is effectively achieved, and 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 2831b, so that the pressure relief mechanism 27a can be broken when the internal pressure of the battery monomer 20 reaches a threshold value, thereby further improving the safety performance of the battery monomer 20.

[0362] In some embodiments of the present application, the battery cell 20 comprises an electrode assembly 22, a housing 21, an electrode terminal 23, a deformable member 25, a first sealing member 29a, a pressure relief mechanism 27a, and a second sealing member 29b. The housing 21 is configured to accommodate the electrode assembly 22, and the housing 21 comprises a shell 213 and a cover 212, both of which are made of steel and are welded together. The cover 212 constitutes a first wall 211 of the housing 21, and the first wall 211 is provided with an electrode lead-out hole, a through hole 2112, and a pressure relief hole 2116, all of which penetrate through opposite sides of the first wall 211 along the thickness direction. The electrode terminal 23 is connected to the electrode lead-out hole and is configured to electrically connect the electrode assembly 22. The deformable member 25 is made of aluminum alloy, covers the through hole 2112, and is configured to be deformable to contact the electrode terminal 23 through the through hole 2112, so that the first wall 211 is electrically connected to the electrode terminal 23. The deformable member 25 is fixedly connected to the first wall 211, and a first connecting material 24 is included at the fixed connection between the deformable member 25 and the first wall 211, and the melting point of the first connecting material 24 is lower than the melting point of the material of the deformable member 25 and / or the melting point of the material of the first wall 211. The first connecting material 24 is a solder. The first sealing member 29a is arranged between the first wall 211 and the deformable member 25 to seal the connection between the first wall 211 and the deformable member 25. The pressure relief mechanism 27a is made of aluminum alloy, covers the pressure relief hole 2116, and is fixedly connected to the first wall 211, and a second connecting material 26 is included at the fixed connection between the pressure relief mechanism 27a and the first wall 211, and the melting point of the second connecting material 26 is lower than the melting point of the material of the pressure relief mechanism 27a and / or the melting point of the material of the first wall 211. The second connecting material 26 is a solder. The second sealing member 29b is arranged between the first wall 211 and the pressure relief mechanism 27a to seal the connection between the first wall 211 and the pressure relief mechanism 27a.

[0363] By adopting the above technical solutions, the connection reliability of the deformable member 25 and the first wall 211 is significantly improved, and the sealing effect at the connection between the first wall 211 and the deformable member 25 is also effectively improved, thereby effectively improving the working reliability of the deformable member 25 and further improving the safety performance of the battery cell 20. In addition, the connection reliability of the pressure relief mechanism 27a and the first wall 211 is also significantly improved, and the communication path between the pressure relief hole 2116 and the internal environment of the housing 21 is effectively blocked, thereby improving the sealing effect at the connection between the first wall 211 and the pressure relief mechanism 27a and improving the working reliability of the pressure relief mechanism 27a, thereby effectively improving the safety performance of the battery cell 20.

[0364] In a second aspect, referring to FIG. 3, the embodiment of the present application provides a battery 100 comprising the battery cell 20 of any of the above embodiments.

[0365] The battery 100 provided by the embodiment of the present application effectively improves the safety performance of the battery 100 due to the use of the battery cell 20 of any of the above embodiments.

[0366] In a third aspect, referring to FIG. 2, the embodiment of the present application provides an energy storage device 2000 comprising the battery 100.

[0367] The energy storage device 2000 provided by the embodiment of the present application effectively improves the safety performance of the energy storage device 2000 due to the use of the battery 100 of any of the above embodiments.

[0368] In a fourth aspect, referring to FIG. 1, the embodiment of the present application provides an electric device comprising the battery 100.

[0369] The electric device provided by the embodiment of the present application effectively improves the safety performance of the electric device due to the use of the battery 100 of any of the above embodiments.

[0370] The above merely provides 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 shall be included in the protection scope of the present application.

Claims

A battery cell, characterized in that, include: Electrode assembly; A housing for accommodating the electrode assembly, the housing including a first wall; Electrode terminals are used for electrically connecting the electrode assembly, and the electrode terminals are disposed on the first wall. A deformable element is configured to deform to contact the electrode terminal so that the first wall is electrically connected to the electrode terminal, wherein the material of the deformable element is different from the material of the first wall. The deformable component is configured to be fixedly connected to the first wall body, and a first connecting material is included at the fixed connection between the deformable component and the first wall body. The melting point of the first connecting material is lower than the melting point of the material of the deformable component and / or the melting point of the material of the first wall body. The battery cell according to claim 1 is characterized in that, The first connecting material is brazing filler metal. The battery cell according to claim 1 or 2 is characterized in that, The deformable member cooperates with the first wall to define a first connecting groove, and the first connecting material is accommodated in the first connecting groove and attached to the inner surface of the first connecting groove. The battery cell according to claim 1 or 2 is characterized in that, The first wall has a first connecting surface, the deformable member has a second connecting surface, the first connecting material is connected between the first connecting surface and the second connecting surface, and the first connecting surface and / or the second connecting surface is a curved surface. The battery cell according to claim 1 or 2 is characterized in that, The first wall has a first connecting surface, the deformable member has a second connecting surface, the first connecting material is connected between the first connecting surface and the second connecting surface, and the first connecting surface and / or the second connecting surface is a rough surface. The battery cell according to any one of claims 1-5 is characterized in that, The first connecting material is disposed around the deformable member. The battery cell according to any one of claims 1-6 is characterized in that, A first limiting structure is provided between the first wall and the deformable member. The first limiting structure is used to limit the relative position of the first wall and the deformable member in a direction perpendicular to the thickness direction of the first wall. The battery cell according to claim 7 is characterized in that, The first limiting structure includes a first limiting part, which is disposed on the first wall and abuts against the deformable member in a direction perpendicular to the thickness direction of the first wall, so as to limit the relative position of the first wall and the deformable member in a direction perpendicular to the thickness direction of the first wall. The battery cell according to claim 8 is characterized in that, The first limiting part protrudes from the first wall body along the thickness direction of the first wall body, and the protrusion height of the first limiting part from the first wall body is 0.1mm-0.6mm. The battery cell according to any one of claims 1-9 is characterized in that, The first wall has a through hole that extends through opposite sides of the first wall along its thickness direction. The deformable member is configured to deform to contact the electrode terminal through the through hole, so that the first wall is electrically connected to the electrode terminal. The battery cell according to claim 10 is characterized in that, The deformable component includes a connecting portion and a deformable portion. The connecting portion is configured to be fixedly connected to the first wall body and surrounds the deformable portion and the through hole. The deformable portion is configured to deform to contact the electrode terminal through the through hole, thereby enabling the first... The wall is electrically connected to the electrode terminals. The battery cell according to claim 10 or 11 is characterized in that, The electrode terminal has a protrusion at the through hole that protrudes toward the deformable member. The deformable member is configured to deform to contact the protrusion through the through hole, so that the first wall is electrically connected to the electrode terminal. The battery cell according to any one of claims 10-12 is characterized in that, The battery cell also includes a first sealing element, which is disposed between the first wall and the deformable element to seal the connection between the first wall and the deformable element. The battery cell according to claim 13 is characterized in that, The first seal is disposed around the through hole. The battery cell according to claim 13 or 14 is characterized in that, The first wall and the deformable member cooperate to clamp the first sealing member along the thickness direction of the first wall. At least one of the first wall and the deformable member is provided with a second limiting structure, which is used to restrict the first sealing member from moving in a direction perpendicular to the thickness direction of the first wall. The battery cell according to claim 15 is characterized in that, The second limiting structure includes a second limiting part, which is disposed on the first wall and abuts against the first sealing member in a direction perpendicular to the thickness direction of the first wall, so as to restrict the first sealing member from moving in a direction perpendicular to the thickness direction of the first wall. The battery cell according to claim 16 is characterized in that, The second limiting part protrudes from the first wall body along the thickness direction of the first wall body, and the protrusion height of the second limiting part from the first wall body is 0.1mm-0.6mm. The battery cell according to any one of claims 13-17 is characterized in that, The first wall has a first sealing surface, and the deformable member has a second sealing surface. The first sealing surface and the second sealing surface cooperate to clamp the first sealing member. In the direction from the first sealing surface to the second sealing surface, the compression rate of the first sealing member is 2%-50%. The battery cell according to any one of claims 1-18 is characterized in that, The battery cell includes two deformable members and two electrode terminals with opposite polarities. The two electrode terminals are insulated from the first wall and are arranged in a one-to-one correspondence with the two deformable members. The battery cell according to any one of claims 1-19 is characterized in that, The battery cell also includes a first insulating member disposed between the electrode terminal and the first wall to insulate the electrode terminal from the first wall. The battery cell according to any one of claims 1-20 is characterized in that, The first wall has a pressure relief hole that penetrates both sides of the first wall along its thickness direction. The battery cell also includes a pressure relief mechanism that covers the pressure relief hole. The material of the pressure relief mechanism is different from that of the first wall. The pressure relief mechanism is fixedly connected to the first wall. A second connecting material is included at the fixed connection between the pressure relief mechanism and the first wall. The melting point of the second connecting material is lower than the melting point of the material of the pressure relief mechanism and / or the melting point of the material of the first wall. The battery cell according to claim 21 is characterized in that, The second connecting material is brazing filler metal. The battery cell according to claim 21 or 22 is characterized in that, The pressure relief mechanism cooperates with the first wall to define a second connecting groove, and the second connecting material is accommodated in the second connecting groove and attached to the inner surface of the second connecting groove. The battery cell according to claim 21 or 22 is characterized in that, The first wall has a third connecting surface, the pressure relief mechanism has a fourth connecting surface, the second connecting material is connected between the third connecting surface and the fourth connecting surface, and the third connecting surface and / or the fourth connecting surface is a curved surface. The battery cell according to claim 21 or 22 is characterized in that, The first wall has a third connecting surface, the pressure relief mechanism has a fourth connecting surface, the second connecting material is connected between the third connecting surface and the fourth connecting surface, and the third connecting surface and / or the fourth connecting surface is a rough surface. The battery cell according to any one of claims 23-25 ​​is characterized in that, The second connecting material is arranged around the pressure relief mechanism. The battery cell according to any one of claims 21-26 is characterized in that, A third limiting structure is provided between the first wall and the pressure relief mechanism. The third limiting structure is used to limit the relative position of the first wall and the pressure relief mechanism in a direction perpendicular to the thickness direction of the first wall. The battery cell according to claim 27 is characterized in that, The third limiting structure includes a third limiting part, which is disposed on the first wall and abuts against the pressure relief mechanism in a direction perpendicular to the thickness direction of the first wall, so as to limit the relative position of the first wall and the pressure relief mechanism in a direction perpendicular to the thickness direction of the first wall. The battery cell according to claim 28 is characterized in that, The third limiting part protrudes from the first wall body along the thickness direction of the first wall body, and the protrusion height of the third limiting part from the first wall body is 0.1mm-0.6mm. The battery cell according to any one of claims 21-29 is characterized in that, The battery cell also includes a second seal, which is disposed between the first wall and the pressure relief mechanism to seal the connection between the first wall and the pressure relief mechanism. The battery cell according to claim 30 is characterized in that, The second seal is arranged around the pressure relief hole. The battery cell according to claim 30 or 31 is characterized in that, The first wall and the pressure relief mechanism cooperate to clamp the second sealing member along the thickness direction of the first wall. At least one of the first wall and the pressure relief mechanism is provided with a fourth limiting structure, which is used to restrict the movement of the second sealing member in a direction perpendicular to the thickness direction of the first wall. The battery cell according to claim 32 is characterized in that, The fourth limiting structure includes a fourth limiting part, which is disposed on the first wall and abuts against the second sealing member in a direction perpendicular to the thickness direction of the first wall, so as to restrict the movement of the second sealing member in a direction perpendicular to the thickness direction of the first wall. The battery cell according to claim 33 is characterized in that, The fourth limiting part protrudes from the first wall body along the thickness direction of the first wall body, and the protrusion height of the fourth limiting part from the first wall body is 0.1mm-0.6mm. The battery cell according to any one of claims 30-34 is characterized in that, The first wall has a third sealing surface, and the pressure relief mechanism has a fourth sealing surface. The third sealing surface and the fourth sealing surface cooperate to clamp the second sealing element. In the direction from the third sealing surface to the fourth sealing surface, the compression rate of the second sealing element is 2%-50%. The battery cell according to any one of claims 21-35 is characterized in that, The pressure relief mechanism is made of aluminum alloy. The battery cell according to any one of claims 21-36 is characterized in that, The battery cell also includes a protective sheet, which is disposed on the side of the first wall facing away from the electrode assembly and covers the pressure relief hole. The pressure relief mechanism is disposed on the side of the first wall facing the electrode assembly. The battery cell according to claim 37 is characterized in that, The protective sheet is adhered to the first wall. The battery cell according to any one of claims 1-38 is characterized in that, The outer casing includes a shell and a cover that covers the shell. The cover constitutes the first wall and is connected to the shell. The material of the first wall is the same as that of the shell. The battery cell according to claim 39 is characterized in that, The shell is welded to the first wall. The battery cell according to any one of claims 1-40 is characterized in that, The deformable part is an aluminum part, and the first wall is a steel part. The battery cell according to any one of claims 1-41 is characterized in that, The battery cell further includes a second insulating member disposed on the side of the first wall facing the electrode assembly. The second insulating member includes an insulating body and a first stop connected to the insulating body. The first stop is disposed opposite to the deformable member. The battery cell according to claim 42 is characterized in that, The first baffle is provided with a first vent hole, which is used to allow gas to flow from the electrode assembly to the deformable part. A battery characterized in that, The battery comprises a single battery cell as described in any one of claims 1-43. An energy storage device, characterized in that, The energy storage device includes the battery as described in claim 44. An electrical appliance, characterized in that, The electrical device includes the battery as described in claim 44.

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