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

Abstract

A battery cell (20), a battery (100), an energy storage device (2000), and an electrical device. The battery cell (20) comprises an electrode assembly (22), a casing (21), an electrode terminal (23), and a deformable member (24). The casing (21) comprises a first wall body (211), the first wall body (211) comprising a first wall portion (2111) and a second wall portion (2112) made of different materials, and the first wall portion (2111) being connected to the second wall portion (2112). The electrode terminal (23) is disposed on the first wall body (211). The deformable member (24) is connected to the first wall portion (2111). The material of the deformable member (24) is the same as the material of the first wall portion (2111), and the deformable member (24) is configured to be deformable so as to be in contact with the electrode terminal (23), so as to cause the first wall body (211) to be electrically connected to the electrode terminal (23).

Description

Battery cell, battery, energy storage device and electric device

[0001] Cross-reference to related applications

[0002] This application is based on Chinese Patent Application No. 202410845839.9, filed on June 27, 2024, entitled "Battery cell, battery, energy storage device and electric device", which is incorporated by reference in its entirety. TECHNICAL FIELD

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

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

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

[0006] SUMMARY

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

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

[0009] An electrode assembly;

[0010] A housing for accommodating the electrode assembly, the housing including a first wall body, the first wall body including a first wall part and a second wall part of different materials, the first wall part and the second wall part being connected;

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

[0012] A deformable member connected to the first wall part, the deformable member being of the same material as the first wall part, the deformable member being configured to be deformable to contact the electrode terminal, so as to electrically connect the first wall body and the electrode terminal.

[0013] The battery cell provided by the embodiments of the present application has the beneficial effects that the deformable member in the battery cell is connected with the first wall part, the material properties of the deformable member are the same as those of the first wall part due to the same material of the deformable member and the first wall part, the material state change difference of the deformable member and the first wall part under the influence of environmental factors such as temperature and air pressure is effectively reduced, the connection reliability of the deformable member and the first wall part is effectively improved, the risk of gap at the connection between the deformable member and the first wall part is effectively reduced, the working reliability of the deformable member is effectively improved, and the safety performance of the battery cell is effectively improved.

[0014] In some embodiments of the present application, the first wall part and the second wall part are connected in a laminated manner along the thickness direction of the first wall body.

[0015] By adopting the above technical solution, the connection area of the first wall part and the second wall part is effectively increased, and the connection reliability of the first wall part and the second wall part is effectively improved.

[0016] In some embodiments of the present application, the first wall body is provided with a via hole, the via hole penetrates through opposite sides of the first wall body along the thickness direction, and the deformable member is configured to be deformable to pass through the via hole and contact the electrode terminal.

[0017] By adopting the above technical solution, the deformable member is facilitated to contact the electrode terminal when the internal pressure of the battery cell reaches a threshold value.

[0018] In some embodiments of the present application, the electrode terminal is provided with a protrusion part protruding towards the deformable member at the via hole, and the deformable member is configured to be deformable to pass through the via hole and contact the protrusion part.

[0019] By adopting the above technical solution, the deformable member is facilitated to contact the electrode terminal when the internal pressure of the battery cell reaches a threshold value.

[0020] In some embodiments of the present application, the via hole penetrates through opposite sides of the first wall part and the second wall part along the thickness direction of the first wall body, and at least part of the deformable member is arranged in the via hole and connected with the hole wall of the via hole located on the first wall part.

[0021] By adopting the above technical solution, not only the relative position of the deformable member and the first wall body is effectively limited, but also the deformable member and the first wall part are facilitated to be connected.

[0022] In some embodiments of the present application, at least part of the second wall part protrudes from the first wall part towards the inside of the via hole and abuts against the deformable member.

[0023] By adopting the technical scheme, the relative position of the deformable member and the first wall body is further limited, the risk of a gap being generated at the connection between the deformable member and the first wall part is further reduced, the working reliability of the deformable member is further improved, and the safety performance of the battery monomer is further improved.

[0024] In some embodiments of the present application, the via penetrates through the first wall part and the second wall part on opposite sides in the thickness direction of the first wall body, at least part of the deformable member is arranged in the via, and at least part of the first wall part protrudes from the second wall part towards the inside of the via and is connected with the deformable member.

[0025] By adopting the technical scheme, the first wall part and the deformable member are conveniently connected, the relative position of the deformable member and the first wall body is effectively limited, the risk of a gap being generated at the connection between the deformable member and the first wall part is further reduced, the working reliability of the deformable member is further improved, and the safety performance of the battery monomer is further improved.

[0026] In some embodiments of the present application, the deformable member includes a connecting part and a deformation part, the deformation part is configured to be deformable to pass through the via and contact the electrode terminal, and the connecting part is arranged around the deformation part and the via and connected with the first wall part.

[0027] By adopting the technical scheme, the deformable member is facilitated to contact the electrode terminal when the internal pressure of the battery monomer reaches a threshold value.

[0028] In some embodiments of the present application, the deformable member is welded with the first wall part.

[0029] By adopting the technical scheme, since the material of the deformable member is the same as that of the first wall part, the melted part of the deformable member can be better combined with the melted part of the first wall part during welding, thereby further improving the connection reliability of the deformable member and the first wall part.

[0030] In some embodiments of the present application, the battery monomer includes two deformable members and two electrode terminals with opposite polarities, the two electrode terminals are arranged in an insulating manner with the first wall body, and the two electrode terminals are arranged in a one-to-one corresponding manner with the two deformable members.

[0031] By adopting the technical scheme, the safety performance of the battery monomer is further improved.

[0032] In some embodiments of the present application, the battery monomer further includes a first insulating member arranged between the electrode terminal and the first wall body to insulate the electrode terminal from the first wall body.

[0033] By adopting the technical scheme, the electrode terminal and the first wall body are conveniently insulated and separated.

[0034] In some embodiments of this application, the first wall has a pressure relief hole that penetrates both sides of the first wall along the thickness direction. The battery cell also includes a pressure relief mechanism covering the pressure relief hole. The pressure relief mechanism is connected to the first wall and the material of the pressure relief mechanism is the same as that of the first wall.

[0035] By adopting the above technical solution, since the material of the pressure relief mechanism is the same as that of the first wall, and the material properties of the pressure relief mechanism are also the same as those of the first wall, the difference in material state changes between the pressure relief mechanism and the first wall under the influence of environmental factors such as temperature and air pressure is effectively reduced. This effectively improves the connection reliability between the pressure relief mechanism and the first wall, effectively reduces the risk of gaps at the connection between the pressure relief mechanism and the first wall, effectively improves the working reliability of the pressure relief mechanism, and further enhances the safety performance of the battery cell.

[0036] In some embodiments of this application, the pressure relief hole penetrates the first wall portion and the second wall portion on opposite sides along the thickness direction of the first wall body, and at least a portion of the pressure relief mechanism is disposed in the pressure relief hole and connected to the hole wall of the pressure relief hole located on the first wall portion.

[0037] By adopting the above technical solution, not only is the relative position of the pressure relief mechanism and the first wall portion effectively limited, but it also facilitates the connection between the pressure relief mechanism and the first wall portion.

[0038] In some embodiments of this application, at least a portion of the second wall protrudes from the first wall toward the interior of the pressure relief hole and abuts against the pressure relief mechanism.

[0039] By adopting the above technical solution, the relative position between the pressure relief mechanism and the first wall is further restricted, the risk of gaps at the connection between the pressure relief mechanism and the first wall is further reduced, thereby further improving the working reliability of the pressure relief mechanism and further improving the safety performance of the battery cell.

[0040] In some embodiments of this application, the pressure relief hole penetrates the opposite sides of the first wall portion and the second wall portion along the thickness direction of the first wall body, at least a portion of the pressure relief mechanism is disposed in the pressure relief hole, and at least a portion of the first wall portion protrudes from the second wall portion toward the interior of the pressure relief hole and is connected to the pressure relief mechanism.

[0041] By adopting the above technical solution, it is not only easier to connect the first wall and the pressure relief mechanism, but also to further limit the relative position of the pressure relief mechanism and the first wall, further reducing the risk of gaps at the connection between the pressure relief mechanism and the first wall, thereby further improving the working reliability of the pressure relief mechanism and further improving the safety performance of the battery cell.

[0042] In some embodiments of this application, the pressure relief mechanism is entirely disposed within the pressure relief hole.

[0043] By adopting the technical scheme, the pressure relief mechanism does not protrude towards the outside of the pressure relief hole, thereby effectively reducing the risk of damage caused by interference between the pressure relief mechanism and other components of the battery monomer, and further improving the safety performance of the battery monomer.

[0044] In some embodiments of the present application, the distance between the port edge of the pressure relief hole close to the electrode assembly and the pressure relief mechanism along the thickness direction of the first wall body is 0mm-0.5mm.

[0045] By adopting the technical scheme, the risk of damage caused by interference between the pressure relief mechanism and other components of the battery monomer is further reduced, thereby further improving the safety performance of the battery monomer.

[0046] In some embodiments of the present application, the first wall body includes a main body and a first boss, the pressure relief hole is opened on the main body, and the first boss is arranged on the surface of the main body away from the electrode assembly and surrounds the pressure relief hole.

[0047] By adopting the technical scheme, in the process of injecting electrolyte into the inside of the battery monomer, the first boss can block the electrolyte from flowing into the pressure relief hole along the surface of the main body away from the electrode assembly, thereby reducing the adverse effects of the electrolyte on the pressure relief mechanism, and further improving the safety performance of the battery monomer.

[0048] In some embodiments of the present application, the protruding height of the first boss relative to the surface of the main body away from the electrode assembly is 0.2mm-0.6mm.

[0049] By adopting the technical scheme, not only the electrolyte is effectively blocked from flowing into the pressure relief hole along the surface of the main body away from the electrode assembly, but also the situation that the protruding height of the first boss is too large is improved, thereby effectively optimizing the height size of the battery monomer and improving the volume energy density of the battery monomer.

[0050] In some embodiments of the present application, the pressure relief mechanism is welded with the first wall part.

[0051] By adopting the technical scheme, since the material of the pressure relief mechanism is the same as that of the first wall part, in the welding process, the melted part of the pressure relief mechanism can be better combined with the melted part of the first wall part, thereby further improving the connection reliability of the pressure relief mechanism and the first wall part.

[0052] In some embodiments of the present application, the battery monomer further includes 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.

[0053] By adopting the technical scheme, foreign matters such as electrolyte, dust and the like can be blocked from entering the pressure relief hole, thereby reducing the adverse effects of the foreign matters on the pressure relief mechanism, and further improving the safety performance of the battery monomer.

[0054] In some embodiments of the present application, the protective sheet is adhered to the first wall body.

[0055] By adopting the above technical solution, the protective sheet is fixed on the first wall body.

[0056] In some embodiments of the present application, the shell comprises a shell body and a cover body arranged on the shell body, the cover body constitutes the first wall body, the second wall body is connected with the shell body, and the material of the second wall body is the same as that of the shell body.

[0057] By adopting the above technical solution, since the material of the second wall body is the same as that of the shell body, the material properties of the second wall body are also the same as those of the shell body, effectively reducing the difference in material state changes of the second wall body and the shell body under the influence of environmental factors such as temperature and air pressure, thereby effectively improving the connection reliability of the second wall body and the shell body, effectively reducing the risk of gaps at the connection between the second wall body and the shell body, and further improving the safety performance of the battery monomer.

[0058] In some embodiments of the present application, a connecting groove is recessed on the edge side of the second wall body, and the connecting groove is used to connect the shell body.

[0059] By adopting the above technical solution, the flatness of the shell is effectively improved.

[0060] In some embodiments of the present application, the wall thickness of the shell body is equal to the depth of the connecting groove.

[0061] By adopting the above technical solution, the flatness of the shell is further improved.

[0062] In some embodiments of the present application, the edge side of the second wall body is stamped to form the connecting groove and the second boss along the thickness direction of the cover body, and the second boss protrudes along the thickness direction of the cover body and away from the connecting groove.

[0063] By adopting the above technical solution, not only is it convenient to form the connecting groove on the edge side of the second wall body, but also the material of the edge side of the second wall body flows along the movement direction of the stamping die, effectively reducing the stamping pressure of the stamping die, thereby effectively reducing the wear amount of the stamping die and prolonging the service life of the stamping die.

[0064] In some embodiments of the present application, the size of the connecting groove along the thickness direction of the cover body is greater than or equal to the size of the second boss along the thickness direction of the cover body.

[0065] By adopting the technical scheme, a part of the edge side material of the second wall portion flows along the movement direction of the stamping die, another part of the edge side material of the second wall portion flows along a direction perpendicular to the movement direction of the stamping die, the situation that the height of the second boss is too large can be improved, thereby effectively optimizing the height size of the battery monomer and improving the volumetric energy density of the battery monomer.

[0066] In some embodiments of the present application, the edge of the cover body close to the corner of the electrode assembly is chamfered.

[0067] By adopting the technical scheme, the assembly efficiency is effectively improved.

[0068] In some embodiments of the present application, the chamfered structure is a bevel angle structure, and the included angle between the bevel angle structure and the inner wall surface of the shell is 30°-60°.

[0069] By adopting the technical scheme, the assembly efficiency is further improved.

[0070] In some embodiments of the present application, the shell is welded with the second wall portion.

[0071] By adopting the technical scheme, since the material of the shell is the same as that of the second wall portion, the melted part of the shell can be better combined with the melted part of the second wall portion in the welding process, thereby further improving the connection reliability of the shell and the second wall portion.

[0072] In some embodiments of the present application, the first wall portion is an aluminum alloy part, and the second wall portion is a steel part.

[0073] By adopting the technical scheme, not only the connection reliability of the deformable part and the first wall portion is improved, but also the structural strength of the first wall body is improved.

[0074] In some embodiments of the present application, the thickness of the first wall portion is 0.2mm-1mm; and / or, the thickness of the second wall portion is 0.2mm-1.5mm.

[0075] By adopting the technical scheme, not only the connection reliability of the deformable part and the first wall portion is improved, but also the structural strength of the first wall body is improved, and the thickness size of the first wall body is optimized, thereby improving the volumetric energy density of the battery monomer.

[0076] In some embodiments of the present application, the battery monomer further comprises a second insulating part arranged on the side of the first wall body facing the electrode assembly, the second insulating part comprises an insulating body and a first blocking portion connected to the insulating body, and the first blocking portion is arranged opposite to the deformable part.

[0077] By adopting the technical scheme, the deformable part is effectively protected, and the risk of damage of the deformable part to other components of the battery cell is effectively reduced.

[0078] In some embodiments of the present application, the first barrier portion is provided with a first air hole for allowing gas to flow from the electrode assembly to the deformable part.

[0079] By adopting the technical scheme, in the case of overcharging of the battery cell, the gas generated by the electrode assembly can reach the deformable part through the first air hole and push the deformable part to move towards the electrode terminal, so that the deformable part and the electrode terminal are in contact with each other, thereby cutting off the charging and discharging circuit of the battery cell, and further improving the safety performance of the battery cell.

[0080] The embodiments of the present application also provide a battery including the battery cell of any one of the above embodiments.

[0081] The battery provided by the embodiments of the present application has the beneficial effect that the battery provided by the embodiments of the present application effectively improves the safety performance of the battery due to the adoption of the battery cell of any one of the above embodiments.

[0082] The embodiments of the present application also provide an energy storage device including the battery.

[0083] The energy storage device provided by the embodiments of the present application has the beneficial effect that the energy storage device provided by the embodiments of the present application effectively improves the safety performance of the energy storage device due to the adoption of the battery of any one of the above embodiments.

[0084] The embodiments of the present application also provide an electrical equipment including the battery.

[0085] The electrical equipment provided by the embodiments of the present application has the beneficial effect that the electrical equipment provided by the embodiments of the present application effectively improves the safety performance of the electrical equipment due to the adoption of the battery of any one of the above embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0086] 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.

[0087] FIG. 1 is a structural schematic diagram of a vehicle provided by the embodiments of the present application;

[0088] FIG. 2 is a structural schematic diagram of an energy storage device provided by the embodiments of the present application;

[0089] FIG. 3 is an explosion schematic diagram of a battery according to an embodiment of the present application;

[0090] FIG. 4 is a structural schematic diagram of a battery monomer according to an embodiment of the present application;

[0091] FIG. 5 is a top view schematic diagram of the battery monomer shown in FIG. 4;

[0092] FIG. 6 is a sectional view schematic diagram of the battery monomer shown in FIG. 5 along the direction of line A-A;

[0093] FIG. 7 is an enlarged schematic diagram of the structure at B of the battery monomer shown in FIG. 6;

[0094] FIG. 8 is a schematic diagram of the connection structure between a first wall body and a deformable member in a battery monomer according to another embodiment of the present application;

[0095] FIG. 9 is a schematic diagram of the connection structure between a first wall body and a deformable member in a battery monomer according to yet another embodiment of the present application;

[0096] FIG. 10 is a schematic diagram of the connection structure between a first wall body and a deformable member in a battery monomer according to still another embodiment of the present application;

[0097] FIG. 11 is an enlarged schematic diagram of the structure at C of the battery monomer shown in FIG. 6;

[0098] FIG. 12 is a schematic diagram of the connection structure between a first wall body and a pressure relief mechanism in a battery monomer according to another embodiment of the present application;

[0099] FIG. 13 is a schematic diagram of the connection structure between a first wall body and a pressure relief mechanism in a battery monomer according to yet another embodiment of the present application;

[0100] FIG. 14 is a schematic diagram of the connection structure between a first wall body and a pressure relief mechanism in a battery monomer according to still another embodiment of the present application;

[0101] FIG. 15 is an enlarged schematic diagram of the structure at D of the battery monomer shown in FIG. 6;

[0102] FIG. 16 is an explosion schematic diagram of a first wall body, a deformable member and a second insulating member in a battery monomer shown in FIG. 4.

[0103] Explanation of reference signs: 1000, vehicle; 2000, energy storage device; 100, battery; 10, box body; 11, first part; 12, second part; 20, battery cell; 21, shell; 211, first wall body; 2111, first wall part; 21111, second flange; 21112, fourth flange; 2112, second wall part; 21121, first flange; 21122, third flange; 2113, via hole; 2114, pressure relief hole; 2115, main body; 2116, first boss; 212, cover body; 2121, connecting groove; 2122, second boss; 2123, chamfer structure; 213, shell; 2131, second wall body; 2132, third wall body; 22, electrode assembly; 23, electrode terminal; 231, terminal body; 2311, protruding part; 232, connecting piece; 24, deformable piece; 241, connecting part; 242, deformation part; 25, pressure relief mechanism; 26, second insulating piece; 261, insulating main body; 262, first blocking part; 2621, first air hole; 263, second blocking part; 2631, second air hole; 27, first insulating piece; 28, protective sheet; 200, controller; 300, motor; 400, battery cabin. DETAILED DESCRIPTION

[0104] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not intended to limit the present application.

[0105] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it can be directly on the other component or indirectly on the other component. When a component is referred to as being "connected to" another component, it can be directly or indirectly connected to the other component. The terms "upper", "lower", "left", "right", and the like indicate the orientation or positional relationship shown in the drawings based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description, and 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 limiting the present application. For those skilled in the art, the specific meanings of the above terms can be understood according to the specific circumstances. The terms "first", "second" are only for the purpose of convenient description, and cannot be understood as indicating or implying relative importance or implying the number of technical features. The meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0106] 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.

[0107] The battery cell, as the smallest unit constituting the battery, generally includes a shell, an electrode assembly and an electrode terminal. The electrode assembly is arranged in the shell, and the electrode terminal is arranged on the wall of the shell. The electrode terminal is connected with the electrode assembly to input or output the electric energy of the battery cell.

[0108] 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 generally 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. When the internal pressure of the battery cell reaches a threshold value, the deformation part of the deformable member will act in the direction of the electrode terminal under the action of the pressure until the deformable member contacts the electrode terminal, so that the electrode terminal is electrically connected 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.

[0109] In the related art, 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 generally made of aluminum material. In order to improve the volumetric energy density of the battery cell, the shell of part of the battery cell is made of steel material. Since the material of the deformable member is different from the material of the shell, the material properties of the deformable member are also different from the material properties of the shell. After the deformable member is connected with the shell, a gap is easily generated at the connection between the deformable member and the shell, so that the deformable member cannot timely generate sufficient internal and external pressure difference, which causes the deformable member to fail to timely deform and contact the electrode terminal, i.e., the charging and discharging circuit of the battery cell cannot be timely cut off, which leads to further deterioration of the overcharging of the battery cell, and even causes thermal runaway, which is not conducive to improving the safety performance of the battery cell.

[0110] In order to improve the safety performance of the battery cell, the deformable member in the battery cell provided by the embodiments of the present application is connected with the first wall part. Since the material of the deformable member is the same as the material of the first wall part, the material properties of the deformable member are also the same as the material properties of the first wall part, which effectively reduces the difference in material state changes of the deformable member and the first wall part under the influence of environmental factors such as temperature and air pressure, thereby effectively improving the connection reliability of the deformable member and the first wall part, effectively reducing the risk of generating a gap at the connection between the deformable member and the first wall part, effectively improving the working reliability of the deformable member, and further effectively improving the safety performance of the battery cell.

[0111] The battery monomer, the battery, the energy storage device using the battery as a power supply and the power consumption device using the battery as a power supply disclosed in the embodiments of the present application, wherein the power consumption device can be but is not limited to a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy and an electric tool, etc. The vehicle can be a fuel automobile, a gas automobile or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile or a range extended automobile, etc. The spacecraft includes an airplane, a rocket, a space shuttle and a spacecraft, etc. The electric toy includes a fixed or mobile electric toy, such as a game machine, an electric automobile toy, an electric ship toy and an electric airplane toy, etc. The electric tool includes a metal cutting electric tool, a grinding electric tool, an assembling electric tool and a railway electric tool, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact electric drill, a concrete vibrator and an electric planer, etc.

[0112] A vehicle is taken as an example of a power consumption device in an embodiment of the present application. Please refer to FIG. 1, which is a structural schematic diagram of a vehicle 1000 provided in an embodiment of the present application. The vehicle 1000 can be a fuel automobile, a gas automobile or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile or a range extended automobile, etc. The vehicle 1000 is internally provided with a battery 100, which can be arranged at the bottom or the head or the tail of the vehicle 1000. The battery 100 can be used for power supply of the vehicle 1000, for example, the battery 100 can be used as an operating power supply of the vehicle 1000. The vehicle 1000 can further include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to supply power to the motor 300, for example, to meet the working power demand of the vehicle 1000 during starting, navigation and driving.

[0113] In some embodiments of the present application, the battery 100 can not only be used as an operating power supply of the vehicle 1000, but also be used as a driving power supply of the vehicle 1000, instead of or partially instead of fuel or natural gas to provide driving power for the vehicle 1000.

[0114] Please refer to FIG. 2, which 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 the energy storage device 2000 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 arranged in the battery cabin 400, and the energy storage device 2000 can further include an electric control module, which is used to control the charging and discharging of the battery 100 and monitor the working state of the battery 100, etc., for example, the electric control module is used to monitor the temperature, voltage, current and other parameters of the battery 100.

[0115] Please refer to FIG. 3, which is an exploded schematic view of the battery 100 according to an embodiment of the present application. The battery 100 includes a box 10 and a battery cell 20, and the battery cell 20 is accommodated in the box 10. The box 10 is configured to provide a space for accommodating the battery cell 20, and the box 10 can have various structures. In some embodiments, the box 10 can include a first part 11 and a second part 12, and the first part 11 and the second part 12 are coupled to each other to define a space for accommodating the battery cell 20. The second part 12 can be a hollow structure with one open end, and the first part 11 can be a plate structure. The first part 11 is arranged on the open end of the second part 12 to define the space for accommodating the battery cell 20 together with the second part 12. Alternatively, the first part 11 and the second part 12 can both be hollow structures with one open end, and the open end of the first part 11 is arranged on the open end of the second part 12. Of course, the box 10 formed by the first part 11 and the second part 12 can have various shapes, such as a cylindrical shape, a cuboid shape, etc.

[0116] In some embodiments, the box 10 can be a part of the chassis structure of the vehicle 1000. For example, the box 10 can be at least a part of the floor of the vehicle 1000, or the box 10 can be at least a part of the cross beam and the longitudinal beam of the vehicle 1000.

[0117] In the battery 100, the battery cell 20 can be multiple, and the multiple battery cells 20 can be connected in series, in parallel, or in a mixed manner. The mixed manner means that the multiple battery cells 20 are connected in series and in parallel. The multiple battery cells 20 can be directly connected in series, in parallel, or in a mixed manner, and the whole of the multiple battery cells 20 is accommodated in the box 10. Of course, the battery 100 can also be that the multiple battery cells 20 are connected in series, in parallel, or in a mixed manner to form a battery module, and the multiple battery modules are connected in series, in parallel, or in a mixed manner to form a whole, and the whole is accommodated in the box 10. The battery 100 can further include other functional components. For example, the battery 100 can further include a busbar for electrically connecting the multiple battery cells 20.

[0118] Each battery cell 20 can be a secondary battery cell or a primary battery cell, where the secondary battery cell refers to a battery cell 20 that can be activated by charging after discharging, and the primary battery cell refers to a battery cell 20 that cannot be activated by charging after the battery cell 20 is exhausted. The battery cell 20 can also be a lithium ion battery cell, a sodium ion battery cell, a sodium lithium ion battery cell, a lithium metal battery cell, a sodium metal battery cell, a lithium sulfur battery cell, a magnesium ion battery cell, a nickel hydrogen battery cell, a nickel cadmium battery cell, a lead 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 soft-pack battery cell, or a battery cell of other shapes, and the prismatic battery cell includes a square battery cell, a blade battery cell, a multi-prismatic battery cell, such as a hexagonal battery cell, and the like, without particular limitation.

[0119] Of course, in some embodiments, the battery 100 can not include the case 10, and a plurality of battery cells 20 are electrically connected and assembled into the energy storage device 2000 or the electric device by necessary fixing structures.

[0120] To illustrate the technical solutions provided in the present application, the following will be described in detail in combination with specific drawings and embodiments.

[0121] In a first aspect, in combination with FIGS. 4 to 7, 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, and a deformable member 24. The outer shell 21 is configured to accommodate the electrode assembly 22, and the outer shell 21 includes a first wall body 211, which includes a first wall portion 2111 and a second wall portion 2112 of different materials, and the first wall portion 2111 and the second wall portion 2112 are connected. The electrode terminal 23 is configured to electrically connect the electrode assembly 22, and the electrode terminal 23 is disposed on the first wall body 211. The deformable member 24 is connected to the first wall portion 2111, and the deformable member 24 is made of the same material as the first wall portion 2111. The deformable member 24 is configured to be deformable to contact the electrode terminal 23, so that the first wall body 211 is electrically connected to the electrode terminal 23.

[0122] 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.

[0123] 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.

[0124] 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.

[0125] 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.

[0126] In some embodiments, the separator can be provided in plural, and can be provided between any adjacent positive electrode sheet or negative electrode sheet.

[0127] In other embodiments, the separator can be continuously provided, and can be provided between any adjacent positive electrode sheet or negative electrode sheet by being folded or wound.

[0128] 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.

[0129] 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 24, the electrolyte, and other functional components.

[0130] In some embodiments, the outer shell 21 can include a shell 213 and a cover 212, wherein the shell 213 has a cavity, an opening can be provided on the shell 213, the cavity is communicated with the external environment of the battery monomer 20 through the opening, and the cavity of the shell 213 is isolated from the external environment of the battery monomer 20 by covering the opening of the shell 213 with the cover 212 to form the internal environment of the battery monomer 20. Specifically, the shell 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 shell 213 when it is necessary to encapsulate the inside of the shell 213. The shape of the shell 213 can be determined according to the specific shape and size of the electrode assembly 22, and the shape of the shell 213 can be but not limited to a cuboid, a cylinder, a hexagonal prism, etc. The shape of the cover 212 can be adapted to the shape of the opening of the shell 213, and the shape of the cover 212 can be but not limited to a cuboid, a cylinder, a hexagonal prism, etc.

[0131] The first wall 211 can be any wall of the outer 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 shell 213, that is, the wall of the shell 213 facing the opening. In some embodiments, the cover 212 constitutes the first wall 211, the shell 213 includes a second wall 2131 and a third wall 2132, the third wall 2132 is arranged around the second wall 2131 and connected with the periphery of the second wall 2131 to define the above-mentioned cavity, the first wall 211 is covered on the opening of the shell 213, and the first wall 211 is arranged opposite to the second wall 2131.

[0132] The first wall part 2111 and the second wall part 2112 are two parts connected with each other in the first wall 211. The connection mode of the first wall part 2111 and the second wall part 2112 can be but not limited to press-fit connection, welding, adhesion, etc.

[0133] In some embodiments, the first wall part 2111 and the second wall part 2112 can jointly constitute the main part of the first wall 211, which is covered on the opening of the shell 213 to isolate the cavity of the shell 213 from the external environment of the battery monomer 20, and the first wall part 2111 is further connected with the deformable member 24.

[0134] In other embodiments, the second wall part 2112 can be taken as the main part of the first wall 211, which is covered on the opening of the shell 213 to isolate the cavity of the shell 213 from the external environment of the battery monomer 20, and the first wall part 2111 can be connected to the second wall part 2112 near the deformable member 24 and connected with the deformable member 24.

[0135] In some embodiments, the first wall portion 2111 can be a main part of the first wall body 211, which covers the opening of the shell 213 to isolate the cavity of the shell 213 from the external environment of the battery cell 20, and the first wall portion 2111 is connected with the deformable member 24. The second wall portion 2112 is connected to any part of the first wall portion 2111, and the second wall portion 2112 can be used to connect other components of the battery cell 20 or as a functional part of the first wall body 211, for example, the second wall portion 2112 as a reinforcing part of the first wall body 211.

[0136] The first wall portion 2111 and the second wall portion 2112 are made of different materials, for example, the first wall portion 2111 is made of aluminum alloy, and the second wall portion 2112 is made of steel, or the first wall portion 2111 is made of steel, and the second wall portion 2112 is made of aluminum alloy.

[0137] The deformable member 24 is a component for short-circuiting the positive electrode and the negative electrode of the battery cell 20 in the case of overcharge of the battery cell 20. The deformable member 24 is connected with the first wall portion 2111, and the connection mode of the deformable member 24 and the first wall portion 2111 can be, but is not limited to, welding, press-fit connection, etc. In the case of overcharge of the battery cell 20, the electrode assembly 22 will generate more gas, and as the gas increases, the internal pressure of the battery cell 20 will also increase. When the internal pressure of the battery cell 20 reaches a threshold value, the pressure acts on the side of the deformable member 24 facing the electrode assembly 22, causing at least part of the deformable member 24 to move in the direction of the electrode terminal 23 until the deformable member 24 contacts the electrode terminal 23, so that the electrode terminal 23 is electrically connected with the shell 21, thereby cutting off the charge-discharge circuit of the battery cell 20.

[0138] In some embodiments, the first wall body 211 is provided with a through hole 2113 penetrating through opposite sides of the first wall body 211 along the thickness direction. The deformable member 24 includes a connecting portion 241 and a deforming portion 242. The connecting portion 241 is arranged around the deforming portion 242 and the through hole 2113 and connected with the first wall portion 2111 to form a ring-shaped sealing boundary, so as to seal the through hole 2113 by the deformable member 24. The deforming portion 242 is capable of deforming under pressure and moving towards the electrode terminal 23 until the deforming portion 242 contacts the electrode terminal 23, so as to electrically connect the electrode terminal 23 with the shell 21. The connecting portion 241 and the deforming portion 242 can be integrally formed, for example, the deformable member 24 is integrally formed by stamping process. The peripheral part of the deformable member 24 forms the connecting portion 241, and the middle part of the deformable member 24 forms the deforming portion 242. The connecting portion 241 and the deforming portion 242 can also be formed separately and then connected to form an integral whole, for example, the connecting portion 241 and the deforming portion 242 are welded after being formed separately.

[0139] The same material of the deformable member 24 and the first wall portion 2111 means that the deformable member 24 and the first wall portion 2111 are made of the same material, for example, the deformable member 24 and the first wall portion 2111 are made of aluminum alloy, or the deformable member 24 and the first wall portion 2111 are made of steel.

[0140] The electrode terminal 23 is a component electrically connected with the electrode assembly 22 for outputting electric energy of the battery monomer 20 or inputting electric energy to the battery monomer 20. The electrode terminal 23 is arranged on the first wall body 211. Part of the electrode terminal 23 extends into the internal environment of the battery monomer 20 and is directly or indirectly connected with the tab of the electrode assembly 22. Another part of the electrode terminal 23 is exposed to the external environment of the battery monomer 20 and is connected with the bus member, the sampling device and other components.

[0141] In some embodiments, in order to improve the overcurrent capacity of the electrode terminal 23, the projection shape of the electrode terminal 23 along the thickness direction of the first wall body 211 is substantially square, so as to increase the overcurrent area of the electrode terminal 23 and improve the overcurrent capacity of the electrode terminal 23.

[0142] 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 shapes, for example, circular.

[0143] In some embodiments, the electrode terminal 23 comprises a terminal body 231 and a connecting piece 232, an electrode lead-out hole is formed on the first wall body 211, the terminal body 231 is arranged on the side of the first wall body 211 away from the electrode assembly 22, the connecting piece 232 is fixedly arranged in the electrode lead-out hole, the connecting piece 232 is connected to the terminal body 231 and electrically connected to the electrode assembly 22, so that the electrode assembly 22 is electrically connected to the terminal body 231, at least part of the terminal body 231 is arranged opposite to the through hole 2113 of the first wall body 211, in the case that the internal pressure of the battery monomer 20 reaches a threshold value, the deformation part 242 of the deformable piece 24 acts towards the terminal body 231 through the through hole 2113, so that the deformation part 242 is in contact with the terminal body 231. The connection mode of the connecting piece 232 and the first wall body 211 can be riveting, threaded connection and the like, but is not limited to the above.

[0144] Of course, in other embodiments, the electrode terminal 23 can be in a columnar structure and fixedly arranged in the electrode lead-out hole.

[0145] In some embodiments, the number of electrode terminals 23 is two, one electrode terminal 23 is a positive electrode terminal, and the other electrode terminal 23 is a negative electrode terminal, the positive electrode terminal is electrically connected to the positive electrode lug of the electrode assembly 22, and the negative electrode terminal is electrically connected to the negative electrode lug of the electrode assembly 22.

[0146] The deformable piece 24 in the battery monomer 20 provided by the embodiments of the present application is connected to the first wall part 2111, since the material of the deformable piece 24 is the same as that of the first wall part 2111, the material characteristics of the deformable piece 24 are also the same as those of the first wall part 2111, which effectively reduces the difference in material state changes of the deformable piece 24 and the first wall part 2111 under the influence of environmental factors such as temperature and air pressure, thereby effectively improving the connection reliability of the deformable piece 24 and the first wall part 2111, effectively reducing the risk of gaps at the connection between the deformable piece 24 and the first wall part 2111, effectively improving the working reliability of the deformable piece 24, and further effectively improving the safety performance of the battery monomer 20.

[0147] In some embodiments of the present application, referring to FIG. 7, the first wall part 2111 and the second wall part 2112 are connected in a laminated manner along the thickness direction of the first wall body 211.

[0148] It can be understood that in the present embodiment, the first wall part 2111 and the second wall part 2112 are both in a plate-like structure, and the first wall part 2111 and the second wall part 2112 jointly constitute the main part of the first wall body 211. The first wall part 2111 can be laminated on the side of the second wall part 2112 away from the electrode assembly 22, or the first wall part 2111 can be laminated on the side of the second wall part 2112 facing the electrode assembly 22.

[0149] In some embodiments, the two plates in the stacked arrangement can be rolled into a composite plate, and then the composite plate can be cut according to the preset size and profile shape of the first wall body 211 to obtain a base plate, and the base plate can be punched to form the first wall body 211.

[0150] Of course, in other embodiments, the two plates can also be directly cut according to the preset size and profile shape of the first wall body 211 to obtain two base plates, and the two base plates can be stacked and connected to form the first wall body 211, for example, the two base plates are stacked and welded to form the first wall body 211, or the two base plates are stacked and bonded to form the first wall body 211.

[0151] By adopting the above technical solution, the connection area of the first wall part 2111 and the second wall part 2112 is effectively increased, thereby effectively improving the connection reliability of the first wall part 2111 and the second wall part 2112.

[0152] In some embodiments of the present application, referring to FIG. 7, the electrode terminal 23 is provided with a protrusion 2311 protruding in a direction close to the deformable member 24 at the via hole 2113, and the deformable member 24 is configured to be deformable to contact the protrusion 2311 through the via hole 2113.

[0153] In some embodiments, the electrode terminal 23 includes a terminal body 231, and a portion of the terminal body 231 opposite the via hole 2113 is protrudingly arranged in a direction close to the deformable member 24 to form the protrusion 2311. At least part of the protrusion 2311 can extend into the via hole 2113 to shorten the distance between the terminal body 231 and the deformable member 24 along the thickness direction of the first wall body 211, and the protrusion 2311 can pass through the via hole 2113 or can not pass through the via hole 2113.

[0154] By adopting the above technical solution, the deformable member 24 is facilitated to contact the electrode terminal 23 when the internal pressure of the battery cell 20 reaches a threshold value.

[0155] In some embodiments of the present application, referring to FIGS. 7 and 8, the via hole 2113 penetrates through the opposite sides of the first wall part 2111 and the second wall part 2112 along the thickness direction of the first wall body 211, and at least part of the deformable member 24 is arranged in the via hole 2113 and connected with the hole wall of the via hole 2113 located on the first wall part 2111.

[0156] In some embodiments, the first wall part 2111 and the second wall part 2112 are stacked and connected along the thickness direction of the first wall body 211, and the via hole 2113 penetrates through the first wall part 2111 and the second wall part 2112 along the thickness direction of the first wall body 211.

[0157] As an example, referring to FIG. 7, the first wall portion 2111 is located on the side of the second wall portion 2112 facing the electrode assembly 22.

[0158] As an example, referring to FIG. 8, the first wall portion 2111 is located on the side of the second wall portion 2112 facing away from the electrode assembly 22.

[0159] In some embodiments, the inner peripheral contour shape of the through hole 2113 can be adapted to the outer peripheral contour shape of the deformable member 24, for example, the inner peripheral contour shape of the through hole 2113 and the outer peripheral contour shape of the deformable member 24 are both circular.

[0160] By adopting the above technical solution, not only the relative position of the deformable member 24 and the first wall body 211 is effectively limited, but also the deformable member 24 and the first wall portion 2111 are facilitated to be connected.

[0161] In some embodiments of the present application, referring to FIG. 7 and FIG. 8, at least part of the second wall portion 2112 protrudes from the first wall portion 2111 towards the inside of the through hole 2113 and abuts against the deformable member 24.

[0162] In some embodiments, referring to FIG. 7, the first wall portion 2111 and the second wall portion 2112 are stacked along the thickness direction of the first wall body 211, the first wall portion 2111 is located on the side of the second wall portion 2112 facing the electrode assembly 22, and the through hole 2113 penetrates the first wall portion 2111 and the second wall portion 2112 along the thickness direction of the first wall body 211. The connecting portion 241 of the deformable member 24 is connected with the hole wall of the through hole 2113 located on the first wall portion 2111, so as to limit the movement of the deformable member 24 in the direction perpendicular to the thickness direction of the first wall body 211 under the action of external force. In the direction perpendicular to the thickness direction of the first wall body 211, at least part of the second wall portion 2112 protrudes from the first wall portion 2111 towards the inside of the through hole 2113 to form a first flange 21121, and the first flange 21121 abuts against the connecting portion 241, so as to limit the movement of the deformable member 24 in the thickness direction of the first wall body 211 and in the direction away from the electrode assembly 22 under the action of external force. In the case where the internal pressure of the battery monomer 20 reaches a threshold value, the deformation portion 242 of the deformable member 24 acts through the through hole 2113 in the direction of the electrode terminal 23, so as to make the deformation portion 242 contact the electrode terminal 23.

[0163] In some other embodiments, referring to FIG. 8, the first wall portion 2111 and the second wall portion 2112 are stacked along the thickness direction of the first wall body 211, and the first wall portion 2111 is located on the side of the second wall portion 2112 away from the electrode assembly 22. The via hole 2113 penetrates the first wall portion 2111 and the second wall portion 2112 along the thickness direction of the first wall body 211. The connecting portion 241 of the deformable member 24 is connected to the hole wall of the via hole 2113 on the first wall portion 2111 to limit the movement of the deformable member 24 in the direction perpendicular to the thickness direction of the first wall body 211 under the action of an external force. In the direction perpendicular to the thickness direction of the first wall body 211, at least part of the second wall portion 2112 protrudes from the first wall portion 2111 towards the inside of the via hole 2113 to form a first flange 21121, and the first flange 21121 abuts against the connecting portion 241 to limit the movement of the deformable member 24 in the thickness direction of the first wall body 211 and towards the electrode assembly 22 under the action of an external force. When the internal pressure of the battery monomer 20 reaches a threshold value, the pressure acts on the deformation portion 242 of the deformable member 24 through the via hole 2113 and pushes the deformation portion 242 to act in the direction of the electrode terminal 23, so that the deformation portion 242 contacts the electrode terminal 23.

[0164] By adopting the above technical solution, the relative position of the deformable member 24 and the first wall body 211 is further limited, the risk of a gap occurring at the connection between the deformable member 24 and the first wall portion 2111 is further reduced, the working reliability of the deformable member 24 is further improved, and the safety performance of the battery monomer 20 is further improved.

[0165] In some other embodiments of the present application, referring to FIG. 9 and FIG. 10, the via hole 2113 penetrates the first wall portion 2111 and the second wall portion 2112 along the opposite sides of the thickness direction of the first wall body 211, at least part of the deformable member 24 is arranged in the via hole 2113, and at least part of the first wall portion 2111 protrudes from the second wall portion 2112 towards the inside of the via hole 2113 and is connected to the deformable member 24.

[0166] In some embodiments, referring to FIG. 9, the first wall portion 2111 and the second wall portion 2112 are stacked along the thickness direction of the first wall body 211, the first wall portion 2111 is located on the side of the second wall portion 2112 facing the electrode assembly 22, and the through hole 2113 penetrates the first wall portion 2111 and the second wall portion 2112 along the thickness direction of the first wall body 211. The connecting portion 241 of the deformable member 24 is arranged in the through hole 2113, and the outer peripheral wall of the connecting portion 241 is fitted with the hole wall of the through hole 2113 on the second wall portion 2112 to limit the movement of the deformable member 24 in a direction perpendicular to the thickness direction of the first wall body 211 under the action of an external force. At least part of the first wall portion 2111 protrudes from the second wall portion 2112 towards the inside of the through hole 2113 to form a second flange 21111 in a direction perpendicular to the thickness direction of the first wall body 211, and the second flange 21111 is connected with the connecting portion 241 to limit the movement of the deformable member 24 in the thickness direction of the first wall body 211 and towards the electrode assembly 22 under the action of an external force. When the internal pressure of the battery cell 20 reaches a threshold value, the pressure acts on the deformation portion 242 of the deformable member 24 through the through hole 2113 and pushes the deformation portion 242 to act towards the electrode terminal 23, so that the deformation portion 242 contacts the electrode terminal 23.

[0167] In other embodiments, referring to FIG. 10, the first wall portion 2111 and the second wall portion 2112 are stacked along the thickness direction of the first wall body 211, the first wall portion 2111 is located on the side of the second wall portion 2112 away from the electrode assembly 22, and the through hole 2113 penetrates the first wall portion 2111 and the second wall portion 2112 along the thickness direction of the first wall body 211. The connecting portion 241 of the deformable member 24 is arranged in the through hole 2113, and the outer peripheral wall of the connecting portion 241 is fitted with the hole wall of the through hole 2113 on the second wall portion 2112 to limit the movement of the deformable member 24 in a direction perpendicular to the thickness direction of the first wall body 211 under the action of an external force. At least part of the first wall portion 2111 protrudes from the second wall portion 2112 towards the inside of the through hole 2113 to form a second flange 21111 in a direction perpendicular to the thickness direction of the first wall body 211, and the second flange 21111 is connected with the connecting portion 241 to limit the movement of the deformable member 24 in the thickness direction of the first wall body 211 and away from the electrode assembly 22 under the action of an external force. When the internal pressure of the battery cell 20 reaches a threshold value, the deformation portion 242 of the deformable member 24 acts towards the electrode terminal 23 through the through hole 2113, so that the deformation portion 242 contacts the electrode terminal 23.

[0168] By adopting the technical solutions, the first wall portion 2111 and the deformable member 24 are conveniently connected, the relative position of the deformable member 24 and the first wall body 211 is effectively limited, the risk of a gap being generated at the connection between the deformable member 24 and the first wall portion 2111 is further reduced, the working reliability of the deformable member 24 is further improved, and the safety performance of the battery monomer 20 is further improved.

[0169] In some embodiments of the present application, the deformable member 24 is welded to the first wall portion 2111.

[0170] The welding of the deformable member 24 to the first wall portion 2111 means that, under the action of high temperature, at least part of the deformable member 24 and at least part of the first wall portion 2111 are melted, and the melted parts of the deformable member 24 and the first wall portion 2111 are combined with each other, and after the melted parts of the deformable member 24 and the first wall portion 2111 are solidified, the deformable member 24 is connected to the first wall portion 2111.

[0171] The welding method of the deformable member 24 to the first wall portion 2111 can be, but is not limited to, laser welding, electric arc welding, ultrasonic welding, etc.

[0172] By adopting the technical solutions, since the material of the deformable member 24 is the same as that of the first wall portion 2111, the melted part of the deformable member 24 can be better combined with the melted part of the first wall portion 2111 during welding, thereby further improving the connection reliability of the deformable member 24 to the first wall portion 2111.

[0173] In some embodiments of the present application, please refer to FIGS. 4-6, the battery monomer 20 includes two deformable members 24 and two electrode terminals 23 with opposite polarities, the two electrode terminals 23 are insulatively arranged with the first wall body 211, and the two electrode terminals 23 are one-to-one correspondingly arranged with the two deformable members 24.

[0174] 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.

[0175] The insulatively arranging of the two electrode terminals 23 with the first wall body 211 means that insulating structures are arranged between the two electrode terminals 23 and the first wall body 211, and the two insulating structures insulatively separate the two electrode terminals 23 and the first wall body 211.

[0176] The one-to-one correspondence between the two electrode terminals 23 and the two deformable members 24 means that when the internal pressure of the battery monomer 20 reaches a threshold value, one deformable member 24 deforms under the action of pressure and moves towards one electrode terminal 23, and the other deformable member 24 deforms under the action of pressure and moves towards the other electrode terminal 23, until the two deformable members 24 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.

[0177] By adopting the above technical solution, the safety performance of the battery monomer 20 is further improved.

[0178] 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 24 is one. When the internal pressure of the battery monomer 20 reaches a threshold value, the deformable member 24 moves towards the positive electrode terminal under the action of pressure until the deformable member 24 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.

[0179] 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 24 is one. When the internal pressure of the battery monomer 20 reaches a threshold value, the deformable member 24 moves towards the negative electrode terminal under the action of pressure until the deformable member 24 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.

[0180] In some embodiments of the present application, referring to FIG. 7, the battery monomer 20 further comprises a first insulating member 27, which is arranged between the electrode terminal 23 and the first wall body 211 to insulate the electrode terminal 23 from the first wall body 211.

[0181] The first insulating member 27 is 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 first insulating member 27 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.

[0182] In some embodiments, the number of electrode terminals 23 is two, and accordingly, the number of first insulating members 27 is also two. The two first insulating members 27 are arranged in one-to-one correspondence with the two electrode terminals 23 to insulate the two electrode terminals 23 from the first wall body 211.

[0183] By adopting the above technical solutions, the electrode terminal 23 is insulated and separated from the first wall body 211.

[0184] In some embodiments of the present application, referring to FIG. 11, the first wall body 211 is provided with a pressure relief hole 2114 penetrating through opposite sides of the first wall body 211 along the thickness direction, and the battery monomer 20 further comprises a pressure relief mechanism 25 covering the pressure relief hole 2114, the pressure relief mechanism 25 being connected with the first wall part 2111, and the material of the pressure relief mechanism 25 being the same as that of the first wall part 2111.

[0185] The pressure relief mechanism 25 is a mechanism for releasing internal pressure when the internal pressure or temperature of the battery monomer 20 reaches a threshold value. The pressure relief mechanism 25 covers the pressure relief hole 2114 and is connected with the first wall part 2111 to form a ring-shaped sealing boundary, so as to seal the pressure relief hole 2114 with the pressure relief mechanism 25, thereby isolating the internal environment of the battery monomer 20 from the external environment of the battery monomer 20. The connection mode of the pressure relief mechanism 25 and the first wall part 2111 can be, but is not limited to, welding, press-fit connection, etc. When the internal pressure or temperature of the battery monomer 20 reaches the threshold value, the pressure relief mechanism 25 breaks 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 2114, and the high-temperature gas can be discharged to the external environment of the battery monomer 20 through the pressure relief hole 2114.

[0186] In some embodiments, the first wall part 2111 and the second wall part 2112 are connected in a laminated manner along the thickness direction of the first wall body 211 and constitute a main part of the first wall body 211, the main part covering the opening of the shell 213 to isolate the cavity of the shell 213 from the external environment of the battery monomer 20, the first wall part 2111 can be arranged on the side of the second wall part 2112 facing the electrode assembly 22, or the first wall part 2111 can be arranged on the side of the second wall part 2112 away from the electrode assembly 22. The pressure relief hole 2114 can penetrate through the first wall part 2111 and the second wall part 2112 along the thickness direction of the first wall body 211, and the pressure relief mechanism 25 covers the pressure relief hole 2114 and is connected with the first wall part 2111.

[0187] In some embodiments, the number of electrode terminals 23 is two, and the pressure relief hole 2114 can be arranged between the two electrode terminals 23.

[0188] The material of the pressure relief mechanism 25 is the same as that of the first wall portion 2111, which means that the pressure relief mechanism 25 and the first wall portion 2111 are made of the same material. Since the material of the deformable member 24 is the same as that of the first wall portion 2111, the material of the deformable member 24, the material of the pressure relief mechanism 25, and the material of the first wall portion 2111 are all the same, for example, the deformable member 24, the pressure relief mechanism 25, and the first wall portion 2111 are all made of aluminum alloy, or for example, the deformable member 24, the pressure relief mechanism 25, and the first wall portion 2111 are all made of steel.

[0189] By adopting the above technical solution, since the material of the pressure relief mechanism 25 is the same as that of the first wall portion 2111, the material properties of the pressure relief mechanism 25 and the first wall portion 2111 are also the same, effectively reducing the difference in material state changes of the pressure relief mechanism 25 and the first wall portion 2111 under the influence of environmental factors such as temperature, air pressure, etc., thereby effectively improving the connection reliability of the pressure relief mechanism 25 and the first wall portion 2111, effectively reducing the risk of gaps at the connection of the pressure relief mechanism 25 and the first wall portion 2111, effectively improving the working reliability of the pressure relief mechanism 25, and further improving the safety performance of the battery monomer 20.

[0190] In some embodiments of the present application, referring to FIGS. 11 and 12, the pressure relief hole 2114 penetrates through the first wall portion 2111 and the second wall portion 2112 on opposite sides of the thickness direction of the first wall body 211, and at least part of the pressure relief mechanism 25 is arranged in the pressure relief hole 2114 and connected with the hole wall of the pressure relief hole 2114 on the first wall portion 2111.

[0191] In some embodiments, the first wall portion 2111 and the second wall portion 2112 are connected in a laminated manner along the thickness direction of the first wall body 211, and the pressure relief hole 2114 penetrates through the first wall portion 2111 and the second wall portion 2112 along the thickness direction of the first wall body 211.

[0192] As an example, referring to FIG. 11, the first wall portion 2111 is located on the side of the second wall portion 2112 facing the electrode assembly 22.

[0193] As an example, referring to FIG. 12, the first wall portion 2111 is located on the side of the second wall portion 2112 away from the electrode assembly 22.

[0194] In some embodiments, the inner peripheral contour shape of the pressure relief hole 2114 can be matched with the outer peripheral contour shape of the pressure relief mechanism 25, for example, the inner peripheral contour shape of the pressure relief hole 2114 and the outer peripheral contour shape of the pressure relief mechanism 25 are both elliptical.

[0195] By adopting the technical scheme, the relative position of the pressure relief mechanism 25 and the first wall body 211 is effectively limited, and the pressure relief mechanism 25 and the first wall body 211 are conveniently connected.

[0196] In some embodiments of the present application, referring to FIGS. 11 and 12, at least part of the second wall portion 2112 protrudes from the first wall portion 2111 towards the inside of the pressure relief hole 2114 and abuts against the pressure relief mechanism 25.

[0197] In some embodiments, referring to FIG. 11, the first wall portion 2111 and the second wall portion 2112 are arranged in a stacked manner along the thickness direction of the first wall body 211, the first wall portion 2111 is located on the side of the second wall portion 2112 facing the electrode assembly 22, and the pressure relief hole 2114 penetrates the first wall portion 2111 and the second wall portion 2112 along the thickness direction of the first wall body 211. The pressure relief mechanism 25 is connected to the hole wall of the pressure relief hole 2114 located on the first wall portion 2111, so as to limit the movement of the pressure relief mechanism 25 in a direction perpendicular to the thickness direction of the first wall body 211 under the action of an external force. In the direction perpendicular to the thickness direction of the first wall body 211, at least part of the second wall portion 2112 protrudes from the first wall portion 2111 towards the inside of the pressure relief hole 2114 to form a third flange 21122, and the third flange 21122 abuts against the pressure relief mechanism 25, so as to limit the movement of the pressure relief mechanism 25 in the thickness direction of the first wall body 211 and away from the electrode assembly 22 under the action of an external force.

[0198] In some other embodiments, referring to FIG. 12, the first wall portion 2111 and the second wall portion 2112 are arranged in a stacked manner along the thickness direction of the first wall body 211, the first wall portion 2111 is located on the side of the second wall portion 2112 away from the electrode assembly 22, and the pressure relief hole 2114 penetrates the first wall portion 2111 and the second wall portion 2112 along the thickness direction of the first wall body 211. The pressure relief mechanism 25 is connected to the hole wall of the pressure relief hole 2114 located on the first wall portion 2111, so as to limit the movement of the pressure relief mechanism 25 in a direction perpendicular to the thickness direction of the first wall body 211 under the action of an external force. In the direction perpendicular to the thickness direction of the first wall body 211, at least part of the second wall portion 2112 protrudes from the first wall portion 2111 towards the inside of the pressure relief hole 2114 to form a third flange 21122, and the third flange 21122 abuts against the pressure relief mechanism 25, so as to limit the movement of the pressure relief mechanism 25 in the thickness direction of the first wall body 211 and towards the electrode assembly 22 under the action of an external force.

[0199] By adopting the technical scheme, the relative position of the pressure relief mechanism 25 and the first wall body 211 is further limited, the risk of a gap occurring at the connection between the pressure relief mechanism 25 and the first wall portion 2111 is further reduced, the working reliability of the pressure relief mechanism 25 is further improved, and the safety performance of the battery monomer 20 is further improved.

[0200] In some embodiments, referring to FIG. 13, the first wall portion 2111 and the second wall portion 2112 are arranged in a stacked manner along the thickness direction of the first wall body 211, the first wall portion 2111 is located on the side of the second wall portion 2112 facing the electrode assembly 22, and the pressure relief hole 2114 penetrates the first wall portion 2111 and the second wall portion 2112 along the thickness direction of the first wall body 211. At least part of the pressure relief mechanism 25 is arranged in the pressure relief hole 2114, and the outer peripheral wall of the pressure relief mechanism 25 is fitted with the hole wall of the pressure relief hole 2114 on the second wall portion 2112 to limit the movement of the pressure relief mechanism 25 in a direction perpendicular to the thickness direction of the first wall body 211 under the action of an external force. In a direction perpendicular to the thickness direction of the first wall body 211, at least part of the first wall portion 2111 protrudes from the second wall portion 2112 towards the inside of the pressure relief hole 2114 to form a fourth protruding flange 21112, and the fourth protruding flange 21112 is connected with the pressure relief mechanism 25 to limit the movement of the pressure relief mechanism 25 in the thickness direction of the first wall body 211 and towards the direction close to the electrode assembly 22 under the action of an external force.

[0201] In some embodiments, referring to FIG. 13, the first wall portion 2111 and the second wall portion 2112 are arranged in a stacked manner along the thickness direction of the first wall body 211, the first wall portion 2111 is located on the side of the second wall portion 2112 facing the electrode assembly 22, and the pressure relief hole 2114 penetrates the first wall portion 2111 and the second wall portion 2112 along the thickness direction of the first wall body 211. At least part of the pressure relief mechanism 25 is arranged in the pressure relief hole 2114, and the outer peripheral wall of the pressure relief mechanism 25 is fitted with the hole wall of the pressure relief hole 2114 on the second wall portion 2112 to limit the movement of the pressure relief mechanism 25 in a direction perpendicular to the thickness direction of the first wall body 211 under the action of an external force. In a direction perpendicular to the thickness direction of the first wall body 211, at least part of the first wall portion 2111 protrudes from the second wall portion 2112 towards the inside of the pressure relief hole 2114 to form a fourth protruding flange 21112, and the fourth protruding flange 21112 is connected with the pressure relief mechanism 25 to limit the movement of the pressure relief mechanism 25 in the thickness direction of the first wall body 211 and towards the direction close to the electrode assembly 22 under the action of an external force.

[0202] In some embodiments, referring to FIG. 13, the first wall portion 2111 and the second wall portion 2112 are arranged in a stacked manner along the thickness direction of the first wall body 211, the first wall portion 2111 is located on the side of the second wall portion 2112 facing the electrode assembly 22, and the pressure relief hole 2114 penetrates the first wall portion 2111 and the second wall portion 2112 along the thickness direction of the first wall body 211. At least part of the pressure relief mechanism 25 is arranged in the pressure relief hole 2114, and the outer peripheral wall of the pressure relief mechanism 25 is fitted with the hole wall of the pressure relief hole 2114 on the second wall portion 2112 to limit the movement of the pressure relief mechanism 25 in a direction perpendicular to the thickness direction of the first wall body 211 under the action of an external force. In a direction perpendicular to the thickness direction of the first wall body 211, at least part of the first wall portion 2111 protrudes from the second wall portion 2112 towards the inside of the pressure relief hole 2114 to form a fourth protruding flange 21112, and the fourth protruding flange 21112 is connected with the pressure relief mechanism 25 to limit the movement of the pressure relief mechanism 25 in the thickness direction of the first wall body 211 and towards the direction close to the electrode assembly 22 under the action of an external force.

[0203] By adopting the technical scheme, the first wall portion 2111 and the pressure relief mechanism 25 are conveniently connected, the relative position of the pressure relief mechanism 25 and the first wall body 211 is further limited, the risk of a gap occurring at the connection between the pressure relief mechanism 25 and the first wall portion 2111 is further reduced, and thus the working reliability of the pressure relief mechanism 25 is further improved, and the safety performance of the battery monomer 20 is further improved.

[0204] In some embodiments of the present application, referring to FIG. 11, the pressure relief mechanism 25 is entirely arranged in the pressure relief hole 2114, that is, the pressure relief mechanism 25 does not protrude outward from the pressure relief hole 2114.

[0205] By adopting the technical scheme, the pressure relief mechanism 25 does not protrude outward from the pressure relief hole 2114, and thus the risk of damage caused by interference between the pressure relief mechanism 25 and other components of the battery monomer 20 is effectively reduced, and the safety performance of the battery monomer 20 is further improved.

[0206] In some embodiments of the present application, referring to FIG. 11, the distance H3 between the port edge of the pressure relief hole 2114 close to the electrode assembly 22 and the pressure relief mechanism 25 along the thickness direction of the first wall body 211 is 0 mm-0.5 mm.

[0207] The distance H3 between the port edge of the pressure relief hole 2114 close to the electrode assembly 22 and the pressure relief mechanism 25 along the thickness direction of the first wall body 211 can be determined according to actual application needs, and can be 0 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, etc.

[0208] By adopting the technical scheme, the risk of damage caused by interference between the pressure relief mechanism 25 and other components of the battery monomer 20 is further reduced, and thus the safety performance of the battery monomer 20 is further improved.

[0209] In some embodiments of the present application, referring to FIGS. 11-14, the first wall body 211 includes a main body 2115 and a first boss 2116, the pressure relief hole 2114 is arranged on the main body 2115, and the first boss 2116 is arranged on the surface of the main body 2115 away from the electrode assembly 22 and surrounds the pressure relief hole 2114.

[0210] The main body 2115 can be composed of the first wall portion 2111 and the second wall portion 2112, and the main body 2115 is arranged at the opening of the shell 213 to isolate the cavity of the shell 213 from the external environment of the battery monomer 20. The pressure relief hole 2114 is arranged on the main body 2115 and penetrates the main body 2115 along the thickness direction of the first wall body 211.

[0211] The first boss 2116 is arranged on the surface of the main body 2115 away from the electrode assembly 22. The first boss 2116 is arranged around the pressure relief hole 2114, which means that the first boss 2116 has a ring structure, and the port of the pressure relief hole 2114 away from the electrode assembly 22 is located in the inner ring space of the first boss 2116.

[0212] In some embodiments, the first wall portion 2111 and the second wall portion 2112 are connected in a laminated manner along the thickness direction of the first wall body 211, the first wall portion 2111 is located on the side of the second wall portion 2112 facing the electrode assembly 22, and a part of the second wall portion 2112 and the first wall portion 2111 form the main body 2115, and another part of the second wall portion 2112 protrudes in the thickness direction of the first wall body 211 and away from the electrode assembly 22 to form the first boss 2116.

[0213] In some other embodiments, the first wall portion 2111 and the second wall portion 2112 are connected in a laminated manner along the thickness direction of the first wall body 211, the first wall portion 2111 is located on the side of the second wall portion 2112 away from the electrode assembly 22, and a part of the first wall portion 2111 and the second wall portion 2112 form the main body 2115, and another part of the first wall portion 2111 protrudes in the thickness direction of the first wall body 211 and away from the electrode assembly 22 to form the first boss 2116.

[0214] By adopting the above technical solution, in the process of injecting electrolyte into the inside of the battery monomer 20, the first boss 2116 can block the electrolyte from flowing into the pressure relief hole 2114 along the surface of the main body 2115 away from the electrode assembly 22, reducing the adverse effects of the electrolyte on the pressure relief mechanism 25, thereby further improving the safety performance of the battery monomer 20.

[0215] In some embodiments of the present application, referring to FIG. 11, the protruding height H4 of the first boss 2116 relative to the surface of the main body 2115 away from the electrode assembly 22 is 0.2-0.6 mm.

[0216] The protruding height H4 of the first boss 2116 refers to the dimension of the first boss 2116 in the thickness direction of the first wall body 211. The protruding height H4 of the first boss 2116 can be determined according to actual application needs, and can be 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, etc.

[0217] By adopting the above technical solution, not only the electrolyte is effectively blocked from flowing into the pressure relief hole 2114 along the surface of the main body 2115 away from the electrode assembly 22, but also the situation that the protruding height H4 of the first boss 2116 is too large is improved, thereby effectively optimizing the height dimension of the battery monomer 20 and improving the volume energy density of the battery monomer 20.

[0218] In some embodiments of the present application, the pressure relief mechanism 25 is welded to the first wall portion 2111.

[0219] The welding of the pressure relief mechanism 25 to the first wall portion 2111 means that, under the action of high temperature, at least part of the pressure relief mechanism 25 and at least part of the first wall portion 2111 are melted, and the melted parts of the pressure relief mechanism 25 and the first wall portion 2111 are combined with each other, and after the melted parts of the pressure relief mechanism 25 and the first wall portion 2111 are solidified, the pressure relief mechanism 25 is connected to the first wall portion 2111.

[0220] The welding method of the pressure relief mechanism 25 to the first wall portion 2111 can be, but is not limited to, laser welding, electric arc welding, ultrasonic welding, etc.

[0221] By adopting the above technical solution, since the material of the pressure relief mechanism 25 is the same as that of the first wall portion 2111, the melted part of the pressure relief mechanism 25 can be better combined with the melted part of the first wall portion 2111 during welding, thereby further improving the connection reliability of the pressure relief mechanism 25 to the first wall portion 2111.

[0222] In some embodiments of the present application, referring to FIG. 11, the battery monomer 20 further comprises a protective sheet 28, which is arranged on the side of the first wall body 211 away from the electrode assembly 22 and covers the pressure relief hole 2114.

[0223] The protective sheet 28 is a component for closing the external port of the pressure relief hole 2114 to block foreign matters from entering the pressure relief hole 2114. The protective sheet 28 can be a film or a plate. The material of the protective sheet 28 can be, but is not limited to, polyimide, polyvinyl chloride, polyester base material, polyurethane, etc.

[0224] By adopting the above technical solution, foreign matters such as electrolyte and dust can be blocked from entering the pressure relief hole 2114, thereby reducing the adverse effects of foreign matters on the pressure relief mechanism 25, and further improving the safety performance of the battery monomer 20.

[0225] In some embodiments of the present application, the protective sheet 28 is adhered to the first wall body 211.

[0226] By adopting the above technical solution, the protective sheet 28 can be fixed on the first wall body 211.

[0227] In some embodiments of the present application, referring to FIG. 15, the above cover body 212 constitutes the first wall body 211, the second wall portion 2112 is connected to the above shell 213, and the material of the second wall portion 2112 is the same as that of the shell 213.

[0228] In some embodiments, the first wall portion 2111 and the second wall portion 2112 are connected in a laminated manner to form a main body of the first wall body 211, which is arranged at the opening of the shell 213 to isolate the cavity of the shell 213 from the external environment of the battery monomer 20, wherein the first wall portion 2111 is used to connect the deformable member 24 and the pressure relief mechanism 25, and the second wall portion 2112 is used to connect the shell 213.

[0229] The same material of the second wall portion 2112 and the shell 213 means that the second wall portion 2112 and the shell 213 are made of the same material, for example, the shell 213 and the second wall portion 2112 are made of steel, and for example, the shell 213 and the second wall portion 2112 are made of aluminum alloy.

[0230] By using the above technical solution, since the material of the second wall portion 2112 is the same as that of the shell 213, the material properties of the second wall portion 2112 and the shell 213 are also the same, which effectively reduces the difference in material state changes of the second wall portion 2112 and the shell 213 under the influence of environmental factors such as temperature and air pressure, thereby effectively improving the connection reliability of the second wall portion 2112 and the shell 213, effectively reducing the risk of gaps at the connection between the second wall portion 2112 and the shell 213, and further improving the safety performance of the battery monomer 20.

[0231] In some embodiments of the present application, referring to FIG. 15, the side of the second wall portion 2112 is recessed with a connecting groove 2121, and the connecting groove 2121 is used to connect the shell 213.

[0232] In some embodiments, the connecting groove 2121 can be in a ring structure and arranged around the second wall portion 2112, and the third wall body 2132 of the shell 213 is connected to the inside of the connecting groove 2121 away from the side edge of the second wall body 2131.

[0233] By using the above technical solution, the flatness of the outer shell 21 is effectively improved.

[0234] In some embodiments of the present application, referring to FIG. 15, the wall thickness of the shell 213 is equal to the depth H5 of the connecting groove 2121.

[0235] The wall thickness of the shell 213 refers to the thickness of the part of the wall body of the shell 213 connected to the connecting groove 2121, for example, the thickness H6 of the third wall body 2132.

[0236] The depth H5 of the connecting groove 2121 refers to the size of the connecting groove 2121 along the direction perpendicular to the thickness direction of the first wall body 211.

[0237] By using the above technical solution, the flatness of the outer shell 21 is further improved.

[0238] Of course, the wall thickness of the shell 213 can be slightly greater than the depth H5 of the connecting groove 2121 in consideration of manufacturing tolerances, for example, the difference between the wall thickness of the shell 213 and the depth H5 of the connecting groove 2121 is less than or equal to 0.2 mm, or the wall thickness of the shell 213 can be slightly less than the depth H5 of the connecting groove 2121, for example, the difference between the depth H5 of the connecting groove 2121 and the wall thickness of the shell 213 is less than or equal to 0.2 mm.

[0239] In some embodiments of the present application, referring to FIG. 15, the edge side of the second wall portion 2112 is stamped to form the connecting groove 2121 and the second boss 2122 along the thickness direction of the cover 212, and the second boss 2122 protrudes along the thickness direction of the cover 212 and away from the connecting groove 2121.

[0240] In the present embodiment, the cover 212 is formed by stamping. During stamping, the stamping die moves linearly along the thickness direction of the cover 212 to push the material on the edge side of the cover 212 to move along the thickness direction of the cover 212, thereby forming the connecting groove 2121 on one side of the edge side of the cover 212 along the thickness direction of the cover 212 and forming the second boss 2122 on the other side of the edge side of the cover 212 along the thickness direction of the cover 212.

[0241] By adopting the above technical solution, not only is it convenient to form the connecting groove 2121 on the edge side of the second wall portion 2112, but also the material on the edge side of the second wall portion 2112 flows along the movement direction of the stamping die, effectively reducing the stamping pressure of the stamping die, thereby effectively reducing the wear amount of the stamping die and prolonging the service life of the stamping die.

[0242] In some embodiments of the present application, referring to FIG. 15, the height H7 of the connecting groove 2121 is greater than or equal to the height H8 of the second boss 2122, wherein the height H7 of the connecting groove 2121 refers to the dimension of the connecting groove 2121 along the thickness direction of the cover 212, and the height H8 of the second boss 2122 refers to the dimension of the second boss 2122 along the thickness direction of the cover 212.

[0243] By adopting the above technical solution, a part of the material on the edge side of the second wall portion 2112 flows along the movement direction of the stamping die, and another part of the material on the edge side of the second wall portion 2112 flows along a direction perpendicular to the movement direction of the stamping die, which can improve the case that the height H8 of the second boss 2122 is too large, thereby effectively optimizing the height dimension of the battery monomer 20 and improving the volume energy density of the battery monomer 20.

[0244] In some embodiments of the present application, referring to FIG. 15, the edge side of the cover 212 near the corner of the electrode assembly 22 is chamfered as a chamfer structure 2123.

[0245] In some embodiments, the chamfer structure 2123 can be a C chamfer structure, i.e., the corner of the side of the cover body 212 close to the electrode assembly 22 is a bevel angle, and the angle a of the chamfer structure 2123 can be 30°-60°, and specifically can be 30°, 35°, 40°, 45°, 50°, 55°, 60°, etc.

[0246] Of course, in other embodiments, the chamfer structure 2123 can be an R chamfer structure, i.e., the corner of the side of the cover body 212 close to the electrode assembly 22 is a round corner.

[0247] By adopting the above technical solution, the assembly operation of the cover body 212 and the shell 213 is facilitated, and the assembly efficiency is effectively improved.

[0248] In some embodiments of the present application, the shell 213 is welded with the second wall portion 2112.

[0249] The welding of the shell 213 with the second wall portion 2112 means that at least part of the shell 213 and at least part of the second wall portion 2112 are melted under the action of high temperature, and the melted parts of the shell 213 and the second wall portion 2112 are combined with each other, and after the melted parts of the shell 213 and the second wall portion 2112 are solidified, the shell 213 and the second wall portion 2112 are connected.

[0250] The welding method of the shell 213 with the second wall portion 2112 can be, but is not limited to, laser welding, electric arc welding, ultrasonic welding, etc.

[0251] By adopting the above technical solution, since the material of the shell 213 is the same as that of the second wall portion 2112, the melted part of the shell 213 can be better combined with the melted part of the second wall portion 2112 during the welding process, thereby further improving the connection reliability of the shell 213 with the second wall portion 2112.

[0252] In some embodiments of the present application, the first wall portion 2111 is an aluminum alloy part, and the second wall portion 2112 is a steel part.

[0253] In other words, the first wall portion 2111 is made of aluminum alloy, the second wall portion 2112 is made of steel, and correspondingly, the deformable part 24 and the pressure relief mechanism 25 are also made of aluminum alloy.

[0254] In the case of equal volume, the weight of the aluminum alloy part is less than that of the steel part, and the hardness of the steel part is greater than that of the aluminum alloy part. By adopting the above technical solution, not only the connection reliability of the deformable part 24 with the first wall portion 2111 is improved, but also the structural strength of the first wall portion 211 is improved.

[0255] In some embodiments of the present application, referring to FIG. 7, the thickness H1 of the first wall portion 2111 is 0.2-1 mm.

[0256] The thickness H1 of the first wall portion 2111 can be determined according to actual application needs, and can be specifically 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, etc.

[0257] In some embodiments of the present application, referring to FIG. 7, the thickness H2 of the second wall portion 2112 is 0.2-1.5 mm.

[0258] The thickness H2 of the second wall portion 2112 can be determined according to actual application needs, and can be specifically 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, etc.

[0259] In some embodiments of the present application, referring to FIG. 7, the first wall portion 2111 is made of an aluminum alloy, the second wall portion 2112 is made of steel, the first wall portion 2111 and the second wall portion 2112 are connected in a laminated manner along the thickness direction of the first wall body 211, the thickness H1 of the first wall portion 2111 is 0.2-1 mm, and the thickness H2 of the second wall portion 2112 is 0.2-1.5 mm.

[0260] By adopting the above technical solution, the connection reliability of the deformable member 24 and the first wall portion 2111 is improved, the structural strength of the first wall body 211 is improved, the thickness size of the first wall body 211 is optimized, and the volume energy density of the battery monomer 20 is improved.

[0261] In some embodiments of the present application, referring to FIG. 16, the battery monomer 20 further comprises a second insulating member 26 arranged on the side of the first wall body 211 facing the electrode assembly 22, the second insulating member 26 comprises an insulating body 261 and a first blocking portion 262 connected to the insulating body 261, and the first blocking portion 262 is arranged opposite to the deformable member 24.

[0262] The second insulating member 26 refers to a component made of an 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 26 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 and the electrode assembly 22, and reduce the risk of short circuit.

[0263] The insulation main body 261 is a main part of the second insulation member 26, and is used to insulate and separate the first wall body 211 and the electrode assembly 22. The first blocking part 262 is connected to a part of the insulation main body 261 opposite to the deformable member 24, and is used to protect the deformable member 24 and insulate and separate the deformable member 24 and the electrode assembly 22. The first blocking part 262 and the insulation main body 261 can be an integrally formed member, for example, the first blocking part 262 and the insulation main body 261 are integrally formed by injection molding, or the first blocking part 262 and the insulation main body 261 can be separately formed and then connected to form an integral whole, for example, the first blocking part 262 and the insulation main body 261 are bonded.

[0264] By using the above technical solution, the deformable member 24 is effectively protected, and the risk of damage of the deformable member 24 caused by interference with other components of the battery monomer 20 is effectively reduced.

[0265] In some embodiments of the present application, referring to FIG. 16, the first blocking part 262 is provided with a first gas hole 2621, and the first gas hole 2621 is used for gas to flow from the electrode assembly 22 to the deformable member 24.

[0266] The first gas hole 2621 penetrates through the first blocking part 262, so that the gas generated by the electrode assembly 22 can enter the inside of the first blocking part 262 and flow to the deformable member 24. The number of the first gas hole 2621 can be one or multiple. When the number of the first gas hole 2621 is multiple, the multiple first gas holes 2621 can be uniformly distributed on the first blocking part 262.

[0267] In some embodiments, the inside of the first blocking part 262 forms a first cavity, and at least part of the deformable member 24 is accommodated in the first cavity. The first cavity and the cavity of the shell 213 are connected through the first gas hole 2621, so that the gas generated by the electrode assembly 22 can enter the first cavity and flow to the deformable member 24.

[0268] By using the above technical solution, when overcharging occurs in the battery monomer 20, the gas generated by the electrode assembly 22 can reach the deformable member 24 through the first gas hole 2621 and push the deformable member 24 to move towards the electrode terminal 23, so that the deformable member 24 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.

[0269] In some embodiments of the present application, referring to FIG. 16, the second insulation member 26 includes a second blocking part 263 connected to the insulation main body 261, and the second blocking part 263 is arranged opposite to the pressure relief mechanism 25. The second blocking part 263 is provided with a second gas hole 2631, and the second gas hole 2631 is used for gas to flow from the electrode assembly 22 to the pressure relief mechanism 25.

[0270] The second blocking portion 263 is connected to the part of the insulating body 261 opposite to the pressure relief mechanism 25, and functions to protect the pressure relief mechanism 25, and also functions to insulate and separate the pressure relief mechanism 25 from the electrode assembly 22. The first blocking portion 262 and the second blocking portion 263 can be integrally formed with the insulating body 261, for example, the first blocking portion 262 and the second blocking portion 263 are integrally formed with the insulating body 261 by injection molding, or the first blocking portion 262 and the second blocking portion 263 can be respectively formed and then connected to each other to form an integral whole, for example, the first blocking portion 262 and the second blocking portion 263 are respectively bonded to the insulating body 261.

[0271] The second gas hole 2631 penetrates through the second blocking portion 263, so that the gas generated by the electrode assembly 22 can enter the inside of the second blocking portion 263 and flow to the pressure relief mechanism 25, and the number of the second gas hole 2631 can be one or multiple, and in the case where the number of the second gas hole 2631 is multiple, the multiple second gas holes 2631 can be uniformly distributed on the second blocking portion 263.

[0272] In some embodiments, the inside of the second blocking portion 263 forms a second cavity, at least part of the pressure relief mechanism 25 is accommodated in the second cavity, and the second cavity is connected to the cavity of the shell 213 through the second gas hole 2631, so that the gas generated by the electrode assembly 22 can enter the second cavity and flow to the pressure relief mechanism 25.

[0273] By using the above technical solution, the protection effect of the pressure relief mechanism 25 is effectively achieved, and the risk of damage caused by the interference between the pressure relief mechanism 25 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 25 through the second gas hole 2631, so that the pressure relief mechanism 25 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.

[0274] In some embodiments of the present application, referring to FIGS. 7, 11 and 15, the battery cell 20 includes an electrode assembly 22, a housing 21, an electrode terminal 23, a deformable member 24 and a pressure relief mechanism 25. The housing 21 is configured to accommodate the electrode assembly 22, and includes a shell 213 and a cover 212, the cover 212 constituting a first wall 211 of the housing 21, the first wall 211 including a first wall portion 2111 and a second wall portion 2112 made of different materials, the first wall portion 2111 and the second wall portion 2112 being connected in a laminated manner along the thickness direction of the first wall 211. The electrode terminal 23 is configured to electrically connect the electrode assembly 22, and is arranged on the first wall 211. The deformable member 24 is configured to contact the electrode terminal 23 when the internal pressure of the battery cell 20 reaches a threshold value, so as to electrically connect the first wall 211 and the electrode terminal 23. The first wall 211 is provided with a pressure relief hole 2114, the pressure relief hole 2114 penetrating through opposite sides of the first wall 211 along the thickness direction, and the pressure relief mechanism 25 is arranged on the pressure relief hole 2114. The first wall portion 2111, the deformable member 24 and the pressure relief mechanism 25 are all made of aluminum alloy, and the deformable member 24 and the pressure relief mechanism 25 are both welded to the first wall portion 2111. The second wall portion 2112 and the shell 213 are both made of steel, and the second wall portion 2112 is welded to the shell 213.

[0275] By adopting the above technical solutions, the connection reliability between the deformable member 24 and the first wall portion 2111, between the pressure relief mechanism 25 and the first wall portion 2111, between the first wall portion 2111 and the second wall portion 2112, and between the shell 213 and the second wall portion 2112 is improved, thereby effectively reducing the risk of gas generated by the electrode assembly 22 being discharged to the external environment of the housing 21 from other parts except the rupture of the pressure relief mechanism 25, effectively improving the working reliability of the deformable member 24, and thus effectively improving the safety performance of the battery cell 20.

[0276] In a second aspect, referring to FIG. 3, the present application provides a battery 100 including the battery cell 20 of any of the above embodiments.

[0277] The battery 100 provided by the embodiments of the present application effectively improves the safety performance of the battery 100 due to the adoption of the battery cell 20 of any of the above embodiments.

[0278] In a third aspect, referring to FIG. 2, the present application provides an energy storage device 2000 including the battery 100 described above.

[0279] The energy storage device 2000 provided by the embodiments of the present application effectively improves the safety performance of the energy storage device 2000 due to the adoption of the battery 100 of any of the above embodiments.

[0280] In a fourth aspect, referring to FIG. 1, an embodiment of the present application provides a power-using device, which comprises the battery 100 described above.

[0281] The power-using device provided by the embodiments of the present application effectively improves the safety performance of the power-using device due to the adoption of the battery 100 of any one of the above-described embodiments.

[0282] The above merely provides the preferred embodiments of the present application, but not for limiting 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

1. A battery cell, characterized by, The battery monomer comprises two deformable members and two electrode terminals with opposite polarities, the two electrode terminals are arranged to be insulated from the first wall body, and the two deformable members are arranged one by one corresponding to the two electrode terminals. The battery monomer further comprises a first insulating member arranged between the electrode terminal and the first wall body to insulate the electrode terminal from the first wall body. The first wall body is provided with a pressure relief hole penetrating through opposite sides of the first wall body along the thickness direction, and the battery monomer further comprises a pressure relief mechanism arranged at the pressure relief hole, the pressure relief mechanism is connected with the first wall part, and the material of the pressure relief mechanism is the same as that of the first wall part. The pressure relief hole penetrates through the first wall part and the second wall part along the thickness direction of the first wall body, and at least part of the pressure relief mechanism is arranged in the pressure relief hole and connected with the hole wall of the pressure relief hole on the first wall part. ​ 2. The battery cell of claim 1, wherein, ​ 3. The battery cell according to claim 1 or 2, characterized in that, ​ 4. The battery cell of claim 3, wherein, ​ 5. The battery cell according to claim 3 or 4, characterized in that, ​ 6. The battery cell of claim 4, wherein, ​ 7. The battery cell according to claim 3 or 4, characterized in that, ​ 8. The battery cell according to any one of claims 3-7, characterized in that, ​ 9. The battery cell of any one of claims 1-8, wherein, ​ 10. The battery cell of any one of claims 1-9, wherein, ​ 11. The battery cell of any one of claims 1-10, wherein, ​ 12. The battery cell of any one of claims 1-11, wherein, ​ 13. The battery cell of claim 12, wherein, ​ 14. The battery cell of claim 13, wherein, At least a portion of the second wall protrudes from the first wall toward the interior of the pressure relief hole and abuts against the pressure relief mechanism.

15. The battery cell of claim 12, wherein, The pressure relief hole penetrates the first wall portion and the second wall portion on opposite sides along the thickness direction of the first wall body. At least a portion of the pressure relief mechanism is disposed in the pressure relief hole. At least a portion of the first wall portion protrudes from the second wall portion toward the interior of the pressure relief hole and is connected to the pressure relief mechanism.

16. The battery cell of any one of claims 12-15, wherein, All pressure relief mechanisms are located inside the pressure relief holes.

17. The battery cell of claim 16, wherein, The distance between the pressure relief hole near the edge of the electrode assembly and the pressure relief mechanism along the thickness direction of the first wall is 0mm-0.5mm.

18. The battery cell of any one of claims 12-17, wherein, The first wall includes a main body and a first boss. The pressure relief hole is formed on the main body, and the first boss is disposed on the surface of the main body facing away from the electrode assembly and surrounds the pressure relief hole.

19. The battery cell of claim 18, wherein, The protrusion height of the first boss relative to the surface of the main body facing away from the electrode assembly is 0.2mm-0.6mm.

20. The battery cell of any one of claims 12-19, wherein, The pressure relief mechanism is welded to the first wall portion.

21. The battery cell of any one of claims 12-20, wherein, 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.

22. The battery cell of claim 21, wherein, The protective sheet is adhered to the first wall.

23. The battery cell of any one of claims 1-22, wherein, The outer casing includes a shell and a cover disposed on the shell. The cover constitutes the first wall. The second wall is connected to the shell, and the material of the second wall is the same as that of the shell.

24. The battery cell of claim 23, wherein, The second wall portion has a recessed connecting groove on its side, which is used to connect the housing.

25. The battery cell of claim 24, wherein, The wall thickness of the housing is equal to the depth of the connecting groove.

26. The battery cell of claim 24 or 25, wherein, The connecting groove and the second boss are formed by stamping the side of the second wall portion along the thickness direction of the cover. The second boss protrudes along the thickness direction of the cover and in a direction away from the connecting groove.

27. The battery cell of claim 26, wherein, The dimension of the connecting groove along the thickness direction of the cover is greater than or equal to the dimension of the second boss along the thickness direction of the cover.

28. The battery cell of any one of claims 23-27, wherein, The corners of the cover near the electrode assembly are chamfered.

29. The battery cell of claim 28, wherein, The chamfered structure is a beveled angle structure, and the angle between the beveled angle structure and the inner wall surface of the shell is 30°-60°.

30. The battery cell of any one of claims 23-29, wherein, The shell is welded to the second wall portion.

31. The battery cell of any one of claims 1-30, wherein, The first wall portion is made of aluminum alloy, and the second wall portion is made of steel.

32. The battery cell according to claim 31, characterized in that, The thickness of the first wall portion is 0.2 mm to 1 mm; and / or, The thickness of the second wall portion is 0.2mm-1.5mm.

33. The battery cell of any one of claims 1-32, wherein, 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.

34. The battery cell of claim 33, wherein, The first baffle has a first vent hole, which is used to allow gas to flow from the electrode assembly to the deformable part.

35. A battery, comprising: The battery comprises a single battery cell as described in any one of claims 1-34.

36. An energy storage device, comprising: The energy storage device includes the battery as described in claim 35.

37. An electrical device, comprising: The electrical device includes the battery as described in claim 35.

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