Battery monomer, battery and electric device

Abstract

The utility model provides a battery monomer, a battery and a power utilization device, and belongs to the technical field of batteries. Wherein the battery monomer comprises a shell, an electrode assembly and an electrode terminal. The shell is provided with a wall part, and the wall part is provided with a mounting hole. The electrode assembly is housed within the housing. The electrode terminal comprises a pole and a connecting piece, the pole penetrates through the mounting hole and is electrically connected with the electrode assembly, the connecting piece is located on the side, away from the electrode assembly, of the wall part in the thickness direction of the wall part, and the connecting piece is connected to the pole. The connecting piece comprises a first material layer and a second material layer which are stacked in the thickness direction of the wall part, the first material layer is located on the side, away from the electrode assembly, of the second material layer, the first material layer is electrically connected with the pole and used for being connected with the confluence component, and the melting point of the second material layer is higher than that of the first material layer. According to the battery monomer with the structure, the thickness of the first material layer can be optimized while welding penetration of the connecting piece is reduced, so that the space occupied by the connecting piece in the thickness direction of the wall part is reduced.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to international patent application PCT / CN2024 / 070222, filed on January 2, 2024, entitled “Battery Cell, Battery and Electrical Device”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the field of battery technology, and in particular to a battery cell, a battery and an electrical device. Background Art

[0004] In recent years, new energy vehicles have developed by leaps and bounds. In the field of electric vehicles, power batteries, as the power source of electric vehicles, play an irreplaceable and important role. With the vigorous promotion of new energy vehicles, the demand for power battery products is also growing. Batteries, as core components of new energy vehicles, have high requirements for performance in use. The battery cell of a battery usually includes a shell and an electrode assembly contained in the shell, and electrode terminals are provided on the shell. By electrically connecting the electrode terminals to the electrode assembly, the input or output of electrical energy of the battery cell can be realized. However, the electrode terminals of existing battery cells occupy a large space, which leads to a low space utilization rate of the battery cells after being assembled into groups, which is not conducive to improving the energy density of the battery. Utility Model Content

[0005] The embodiments of the present application provide a battery cell, a battery, and an electrical device, which can effectively improve the energy density of the battery.

[0006] In the first aspect, an embodiment of the present application provides a battery cell, comprising a shell, an electrode assembly and an electrode terminal; the shell has a wall portion, the wall portion is provided with a mounting hole, and the mounting hole passes through the wall portion along the thickness direction of the wall portion; the electrode assembly is accommodated in the shell; the electrode terminal comprises a pole and a connector, the pole is passed through the mounting hole, the pole is electrically connected to the electrode assembly, and the connector is located on the side of the wall portion away from the electrode assembly along the thickness direction of the wall portion, and the connector is connected to the pole; wherein the connector comprises a first material layer and a second material layer stacked along the thickness direction of the wall portion, the first material layer is located on the side of the second material layer away from the electrode assembly, the first material layer is electrically connected to the pole and is used to connect to the busbar component, and the melting point of the second material layer is higher than the melting point of the first material layer.

[0007] In the above technical scheme, the electrode terminal includes a pole and a connector, the pole is inserted into the mounting hole, and the connector is located on the side of the wall away from the electrode assembly and is connected to the pole, so as to realize the assembly of the electrode terminal on the wall, by setting the connector as a first material layer and a second material layer stacked along the thickness direction of the wall, the second material layer is located on the side of the first material layer facing the electrode assembly, so that the second material layer is located between the wall and the first material layer, and the melting point of the second material layer is greater than the melting point of the first material layer, so that the second material layer can play a certain separation and barrier role when the first material layer is welded and connected to the collector component for assembly, so as to reduce the risk of the connector being welded through and affecting other components, thereby reducing the risk of the connector being welded through by increasing the thickness of the first material layer. The battery cell adopting this structure can optimize the thickness of the first material layer while reducing the risk of the connector being welded through, so as to reduce the space occupied by the connector in the thickness direction of the wall, thereby effectively improving the space utilization rate of the battery cell after being assembled into a group, which is beneficial to improving the energy density of the battery having such a battery cell.

[0008] In some embodiments, the melting point of the first material layer is MP1, and the melting point of the second material layer is MP2, satisfying MP2-MP1≥200°C.

[0009] In the above technical solution, by setting the melting point of the second material layer to be greater than or equal to 200 degrees Celsius than the melting point of the first material layer, the phenomenon of the second material layer being melted when the first material layer is welded and assembled with the collector component can be further alleviated, thereby further improving the separation effect and barrier effect of the second material layer, thereby further reducing the risk of the connector being welded through.

[0010] In some embodiments, along the thickness direction of the wall portion, the thickness of the first material layer is D1, and the thickness of the second material layer is D2, satisfying 0.1≤D2 / D1≤0.25.

[0011] In the above technical solution, by setting the thickness of the second material layer to be greater than or equal to 0.1 times the thickness of the first material layer, the second material layer has sufficient thickness to separate and block the first material layer and the collector component when they are welded and assembled, so as to alleviate the phenomenon of the second material layer being welded through. By setting the thickness of the second material layer to be less than or equal to 0.25 times the thickness of the first material layer, the phenomenon of excessive waste of the thickness of the second material layer is reduced, which is conducive to reducing the manufacturing cost of the connector, and can save the space occupied by the second material layer in the thickness direction of the wall, which is conducive to improving the space utilization rate of the battery cells after being assembled into groups.

[0012] In some embodiments, the first material layer and the second material layer are compositely connected.

[0013] In the above technical solution, a composite connection structure is adopted to connect the first material layer and the second material layer, which can effectively improve the structural strength and connection stability of the first material layer and the second material layer, and is beneficial to reducing the risk of mutual detachment between the first material layer and the second material layer.

[0014] In some embodiments, the material of the first material layer is aluminum, and the material of the second material layer is steel.

[0015] In the above technical solution, by setting the material of the first material layer as aluminum and correspondingly setting the material of the second material layer as steel, on the one hand, the manufacturing cost of the connecting piece can be reduced, and on the other hand, the melting point of the second material layer is much higher than that of the first material layer, so that the second material layer has a good separation and blocking effect when the first material layer is welded and connected to the busbar component for assembly, thereby effectively reducing the risk of the connecting piece being welded through.

[0016] In some embodiments, the pole column includes a body portion and an abutting portion; the body portion is disposed through the mounting hole along the thickness direction of the wall portion, and the body portion is connected to the connecting piece; the abutting portion abuts against one side of the wall portion facing the electrode assembly, and the abutting portion and the connecting piece cooperate to clamp the wall portion to fasten the electrode terminal to the wall portion.

[0017] In the above technical solution, the pole column is provided with a body portion disposed through the mounting hole, and the abutting portion and the connecting piece are respectively connected to both ends of the body portion in the thickness direction of the wall portion, so that the abutting portion and the connecting piece located on both sides of the wall portion in the thickness direction of the wall portion can cooperate to clamp the wall portion, thereby realizing the assembly of the electrode terminal on the wall portion. The structure is simple and convenient for assembly.

[0018] In some embodiments, the body portion is riveted to the first material layer.

[0019] In the above technical solution, by riveting the body portion of the pole column to the first material layer of the connecting piece, the assembly connection between the pole column and the connecting piece is realized. The structure is simple, convenient for assembly, and has high structural stability, which is beneficial to reducing the phenomenon of connection failure between the pole column and the connecting piece.

[0020] In some embodiments, the electrode terminal is insulatingly mounted on the wall portion.

[0021] In the above technical solution, by insulatingly mounting the electrode terminal on the wall portion, no electrical connection is formed between the electrode terminal and the wall portion. On the one hand, it is convenient for the electrode terminal to input or output the electric energy of the battery cell, and on the other hand, the short-circuit risk of the battery cell can be reduced.

[0022] In some embodiments, the battery cell further includes a first insulating member and a second insulating member; along the thickness direction of the wall portion, at least a part of the first insulating member is disposed between the connecting member and the wall portion, and the first insulating member is configured to insulate and isolate the connecting member and the wall portion; along the thickness direction of the wall portion, at least a part of the second insulating member is disposed between the pole and the wall portion, and the second insulating member is configured to insulate and isolate the pole and the wall portion.

[0023] In the above technical solution, by disposing a first insulating member between the connecting member and the wall portion, the first insulating member can insulate and isolate the wall portion and the connecting member, thereby reducing the risk of short circuit between the wall portion and the connecting member. Correspondingly, by disposing a second insulating member between the pole and the wall portion, the second insulating member can insulate and isolate the wall portion and the pole, thereby reducing the risk of short circuit between the wall portion and the pole. Furthermore, by respectively disposing the first insulating member and the second insulating member on both sides of the wall portion, the electrode terminal can be insulated and mounted on the wall portion.

[0024] In some embodiments, the battery cell further includes a sealing member; the sealing member is disposed between the wall portion and the pole, and at least a part of the sealing member is located in the mounting hole, and the sealing member is configured to seal the gap between the pole and the hole wall surface of the mounting hole.

[0025] In the above technical solution, by disposing a sealing member between the wall portion and the pole of the electrode terminal, and at least a part of the sealing member is located in the mounting hole, the sealing member can seal the gap between the pole and the hole wall surface of the mounting hole, thereby effectively reducing the phenomenon that the electrolyte inside the battery cell overflows from the mounting hole, and improving the use stability and reliability of the battery cell.

[0026] In some embodiments, along the thickness direction of the wall portion, a receiving groove is disposed on a side of the wall portion facing away from the electrode assembly, the mounting hole is disposed on the groove bottom surface of the receiving groove, and at least a part of the first insulating member is received in the receiving groove.

[0027] In the above technical solution, by providing a receiving groove for receiving the first insulating member on a side of the wall portion facing away from the electrode assembly, it is convenient to assemble the first insulating member between the connecting member and the wall portion, which can play a role in assembling and positioning the first insulating member, is beneficial to reducing the assembly difficulty of the first insulating member, and can play a certain protective role for the first insulating member to reduce the phenomena such as wear or damage of the first insulating member during use.

[0028] In some embodiments, the second material layer is welded to the wall portion.

[0029] In the above technical solution, by welding the second material layer of the connecting member to the wall portion, the connecting member of the electrode terminal is electrically connected to the wall portion of the housing, so as to output or input the electric energy of the battery cell. For a battery cell adopting this structure, there is no need to provide an insulating component for insulating isolation between the connecting member and the wall portion, which is beneficial to reducing the manufacturing cost and assembly difficulty of the battery cell.

[0030] In some embodiments, the second material layer is welded to the wall portion to form a weld mark, and the weld mark surrounds the outside of the mounting hole.

[0031] In the above technical solution, by setting the weld mark formed by welding the second material layer and the wall portion to surround the outside of the mounting hole, the weld mark formed by welding the second material layer and the wall portion surrounds the mounting hole, so that the gap between the connecting member and the wall portion can be sealed through the weld mark. Furthermore, there is no need to provide a sealing component for sealing between the pole post and the hole wall surface of the mounting hole, which is beneficial to reducing the manufacturing cost and assembly difficulty of the battery cell.

[0032] In some embodiments, the material of the second material layer is the same as that of the wall portion.

[0033] In the above technical solution, by setting the material of the second material layer to be the same as that of the wall portion, a structure in which the second material and the wall portion are welded with the same material can be realized. On the one hand, the welding difficulty between the second material layer and the wall portion can be reduced, and on the other hand, phenomena such as insufficient welding or welding failure between the second material layer and the wall portion can be reduced, which is beneficial to improving the welding quality between the second material layer and the wall portion.

[0034] In some embodiments, along the thickness direction of the wall portion, a receiving groove is provided on the side of the wall portion facing away from the electrode assembly, the mounting hole is provided on the groove bottom surface of the receiving groove, at least a part of the connecting member is received in the receiving groove, and the second material layer is welded to the groove bottom surface of the receiving groove.

[0035] In the above technical solution, by providing a receiving groove for receiving the connecting member on the side of the wall portion facing away from the electrode assembly, on the one hand, it can play a role in assembling and positioning the connecting member, which is beneficial to reducing the welding difficulty between the wall portion and the second material layer of the connecting member and can improve the welding quality between the wall portion and the second material layer of the connecting member. On the other hand, it can play a certain protective role for the connecting member to reduce phenomena such as wear or damage of the connecting member during use.

[0036] In some embodiments, the housing includes a housing body and an end cap; an accommodating cavity with an opening is formed inside the housing body, and the accommodating cavity is used to accommodate the electrode assembly; the end cap closes the opening; wherein, the end cap is the wall portion.

[0037] In the above technical solution, by setting the wall portion of the outer shell as the end cover for the outer shell to close the opening of the housing, the battery cell with this structure facilitates the assembly of the electrode terminals on the end cover and the assembly and connection of the pole columns of the electrode terminals with the electrode assembly, which is beneficial to reducing the assembly difficulty of the battery cell and improving the production efficiency of the battery cell.

[0038] In some embodiments, the outer shell includes a housing and an end cover; the housing includes a side wall and the wall portion integrally formed, the side wall surrounds the periphery of the wall portion, along the thickness direction of the wall portion, one end of the side wall is connected to the wall portion, and the other end encloses an opening, and the side wall and the wall portion jointly define a receiving cavity for receiving the electrode assembly; the end cover closes the opening.

[0039] In the above technical solution, by setting the wall portion of the outer shell as a wall of the housing opposite to the end cover in the thickness direction of the wall portion, the battery cell with this structure can make the area of the outer shell where the electrode terminals are installed away from the end cover, and there is no direct connection relationship between the wall portion and the end cover, so as to relieve the force generated when components such as the electrode terminals pull or twist the wall portion from acting on the end cover, thereby reducing the risk of connection failure between the end cover and the housing, and further being beneficial to reducing the risk of liquid leakage during the use of the battery cell.

[0040] In a second aspect, the embodiment of the present application further provides a battery, including the above battery cell.

[0041] In some embodiments, the battery further includes a busbar component; the busbar component is welded to the first material layer to electrically connect the busbar component and the pole column.

[0042] In the above technical solution, the busbar component is welded to the first material layer of the connecting member to achieve electrical connection between the busbar component and the electrode terminal, so that the input or output of electrical energy of the battery cell can be realized through the busbar component. Among them, the connecting member is arranged as a first material layer and a second material layer stacked along the thickness direction of the wall portion, and the second material layer is located on the side of the first material layer facing the electrode assembly, so that the second material layer is located between the wall portion and the first material layer, and the melting point of the second material layer is greater than that of the first material layer. When the first material layer is welded to the busbar component for assembly, the second material layer can play a certain role of separation and blocking, so as to reduce the risk that the connecting member is welded through and affects other components. Therefore, there is no need to increase the thickness of the first material layer to reduce the risk of the connecting member being welded through. The battery cell adopting this structure can optimize the thickness of the first material layer while reducing the risk of the connecting member being welded through, so as to reduce the space occupied by the connecting member in the thickness direction of the wall portion, and further effectively improve the space utilization rate of the battery cell after being assembled into a group, which is beneficial to improving the energy density of the battery with such a battery cell.

[0043] In some embodiments, the material of the busbar component is the same as that of the first material layer.

[0044] In the above technical solution, by setting the material of the busbar component to be the same as that of the first material layer, a structure in which the busbar component and the first material layer are welded with the same material can be realized. On the one hand, the welding difficulty between the busbar component and the first material layer can be reduced, and on the other hand, phenomena such as virtual welding or welding failure between the busbar component and the first material layer can be reduced, which is beneficial to improving the welding quality between the busbar component and the first material layer.

[0045] In a third aspect, an embodiment of the present application further provides an electrical device, including the above battery cell, and the battery cell is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0047] Figure 1 A schematic structural diagram of a vehicle provided by some embodiments of the present application;

[0048] Figure 2 An exploded view of the structure of a battery provided by some embodiments of the present application;

[0049] Figure 3Schematic diagram of the structure of a battery cell provided in some embodiments of the present application;

[0050] Figure 4 Exploded view of the structure of a battery cell provided in some embodiments of the present application;

[0051] Figure 5 Partial cross-sectional view of a battery cell provided in some embodiments of the present application;

[0052] Figure 6 Cross-sectional view of the electrode terminal of a battery cell provided in some embodiments of the present application;

[0053] Figure 7 Partial cross-sectional view of a battery cell provided in some other embodiments of the present application.

[0054] Icons: 1000 - vehicle; 100 - battery; 10 - box body; 11 - first box body; 12 - second box body; 20 - battery cell; 21 - outer shell; 211 - wall portion; 2111 - mounting hole; 2112 - receiving groove; 212 - housing; 2121 - opening; 213 - end cover; 22 - electrode assembly; 221 - tab; 23 - electrode terminal; 231 - pole column; 2311 - body portion; 2312 - abutting portion; 232 - connecting member; 2321 - first material layer; 2321a - riveting hole; 2322 - second material layer; 24 - current collecting member; 25 - pressure relief mechanism; 26 - first insulating member; 27 - second insulating member; 28 - seal; 200 - controller; 300 - motor; X - thickness direction of the wall portion. Detailed implementation manners

[0055] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0056] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs; the terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "including" and "having" and any variations thereof in the specification and claims of the present application and the above drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification and claims of the present application or the above drawings are used to distinguish different objects and are not used to describe a specific order or primary-secondary relationship.

[0057] As used in this application, the mention of "embodiment" means that the specific features, structures, or characteristics described in connection with the embodiment may be included in at least one embodiment of this application. The phrase appearing at various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments.

[0058] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect", "attach" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0059] The term "and / or" in this application is merely an association relationship describing associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally represents an "or" relationship between the associated objects before and after.

[0060] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, in different embodiments, the detailed description of the same components is omitted. It should be understood that the thickness, length, width, etc. of various components in the embodiments of this application shown in the drawings, as well as the overall thickness, length, width, etc. of the integrated device, are only illustrative and should not constitute any limitation to this application.

[0061] The "plurality" mentioned in this application refers to two or more (including two).

[0062] In the embodiments of this application, the battery cell may be a secondary battery, which refers to a battery cell that can continue to be used by activating the active material through charging after the battery cell discharges.

[0063] The battery cell may be a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-metal hydride battery, a nickel-cadmium battery, a lead-acid battery, etc., and the embodiments of this application are not limited thereto.

[0064] The battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are embedded and extracted back and forth between the positive electrode and the negative electrode. The separator is disposed between the positive electrode and the negative electrode, which can prevent the short circuit between the positive and negative electrodes and allow the active ions to pass through at the same time.

[0065] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0066] As an example, the positive electrode current collector has two surfaces opposite to each other in its own thickness direction, and the positive electrode active material is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.

[0067] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum with silver plating on the surface, stainless steel with silver plating on the surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as substrates of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0068] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphate, lithium transition metal oxide, and their respective modified compounds. However, the present application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Among them, examples of lithium-containing phosphate may include, but are not limited to, lithium iron phosphate (such as LiFePO4 (which may also be abbreviated as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, a composite material of lithium manganese iron phosphate and carbon, etc. Examples of lithium transition metal oxides may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi1 / 3Co1 / 3Mn1 / 3O2 (which may also be abbreviated as NCM333), LiNi0.5Co0.2Mn0.3O2 (which may also be abbreviated as NCM523), LiNi0.5Co0.25Mn0.25O2 (which may also be abbreviated as NCM211), LiNi0.6Co0.2Mn0.2O2 (which may also be abbreviated as NCM622), LiNi0.8Co0.1Mn0.1O2 (which may also be abbreviated as NCM811), lithium nickel cobalt aluminum oxide (such as LiNi0.85Co0.15Al0.05O2), and their modified compounds, etc.).

[0069] In some embodiments, the positive electrode may employ a porous metal. The porous metal may be porous nickel, porous copper, porous aluminum, porous alloy, etc. When the porous metal serves as the positive electrode, the positive electrode active material may not be provided on the surface of the porous metal, or of course, the positive electrode active material may be provided. As an example, a lithium source material, potassium metal, or sodium metal may also be filled and / or deposited in the porous metal, and the lithium source material is lithium metal and / or lithium-rich material.

[0070] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0071] As an example, the negative electrode current collector may employ a metal foil, porous metal, or composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, nickel, or titanium, etc. may be used. The porous metal may be porous nickel, porous copper, porous aluminum, porous alloy, etc. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as substrates of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0072] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material provided on at least one surface of the negative electrode current collector.

[0073] As an example, the negative electrode current collector has two surfaces opposite to each other in its own thickness direction, and the negative electrode active material is provided on any one or both of the two opposite surfaces of the negative electrode current collector.

[0074] As an example, the negative electrode active material may employ negative electrode active materials known in the art for battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. The silicon-based materials may be selected from at least one of elemental silicon, silicon oxides, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based materials may be selected from at least one of elemental tin, tin oxides, and tin alloys. However, the present application is not limited to these materials, and other conventional materials that can be used as battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0075] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0076] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0077] In some embodiments, the separator is a separator membrane. The types of separator membranes can be various, and any well-known porous structure separator membrane with good chemical stability and mechanical stability can be selected.

[0078] As an example, the material of the separator membrane can include at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator membrane can be a single-layer film or a multi-layer composite film. When the separator membrane is a multi-layer composite film, the materials of each layer can be the same or different. The separator can be a single component located between the positive and negative electrodes, or attached to the surfaces of the positive and negative electrodes.

[0079] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive electrode and the negative electrode, and simultaneously functions to transport ions and isolate the positive and negative electrodes.

[0080] In some embodiments, the battery cell further includes an electrolyte, which functions to conduct ions between the positive and negative electrodes. The electrolyte can be liquid, gel-like, or solid. Among them, the liquid electrolyte includes an electrolyte salt and a solvent.

[0081] In some embodiments, the electrolyte salt can include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluoro(oxalato)borate, lithium bis(oxalato)borate, lithium difluoro-bis(oxalato)phosphate, and lithium tetrafluoro(oxalato)phosphate.

[0082] In some embodiments, the solvent can include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent can also be an ether solvent. The ether solvent can include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether, and crown ether.

[0083] Among them, the gel-like electrolyte includes a polymer as the skeleton network of the electrolyte, combined with an ionic liquid-lithium salt.

[0084] Among them, the solid electrolyte includes a polymer solid electrolyte, an inorganic solid electrolyte, and a composite solid electrolyte.

[0085] As an example, the polymer solid electrolyte can be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, single-ion polymer, polyionic liquid-lithium salt, cellulose, etc.

[0086] As an example, the inorganic solid electrolyte can include oxide solid electrolytes (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON film), sulfide solid electrolytes (crystalline lithium superionic conductor (lithium germanium phosphorus sulfur, argyrodite), amorphous sulfide), and one or more of halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0087] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to the polymer solid electrolyte.

[0088] In some embodiments, the electrode assembly has a wound structure. The positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0089] In some embodiments, the electrode assembly has a stacked structure.

[0090] As an example, multiple positive electrode sheets and multiple negative electrode sheets can be respectively provided, and the multiple positive electrode sheets and the multiple negative electrode sheets are alternately stacked.

[0091] As an example, multiple positive electrode sheets can be provided, and the negative electrode sheet is folded to form multiple stacked folding segments, and one positive electrode sheet is clamped between adjacent folding segments.

[0092] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form multiple stacked folding segments.

[0093] As an example, multiple separators can be provided and are respectively disposed between any adjacent positive electrode sheets or negative electrode sheets.

[0094] As an example, the separator can be continuously provided and is disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0095] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, prismatic, etc.

[0096] In some embodiments, the electrode assembly is provided with tabs, and the tabs can conduct current out of the electrode assembly. The tabs include a positive tab and a negative tab.

[0097] In some embodiments, the battery cell can include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell), or an aluminum plastic film, etc.

[0098] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell or a battery cell of other shapes. The prismatic battery cell includes, but is not limited to, a square shell battery cell, a blade-shaped battery cell, a multi-prismatic battery, and the multi-prismatic battery is, for example, a hexagonal prism battery, etc.

[0099] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide a higher voltage and capacity.

[0100] In some embodiments, the battery can be a battery module. When there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0101] In some embodiments, the battery can be a battery pack. The battery pack includes a box body and battery cells, and the battery cells or battery modules are accommodated in the box body.

[0102] In some embodiments, the box body can be part of the chassis structure of a vehicle. For example, a part of the box body can become at least a part of the floor of the vehicle, or a part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0103] In some embodiments, the battery can be an energy storage device. The energy storage device includes an energy storage container, an energy storage electrical cabinet, etc.

[0104] The battery has outstanding advantages such as high energy density, low environmental pollution, high power density, long service life, wide application range, and small self-discharge coefficient, and is an important part of the development of new energy today. The development of battery technology needs to consider various design factors at the same time. For example, performance parameters such as energy density, cycle life, discharge capacity, charge and discharge rate, etc. In addition, the production quality of the battery during the production process also needs to be considered.

[0105] For a general battery cell, the battery cell usually includes a shell and an electrode assembly contained in the shell, and the shell is equipped with an electrode terminal. By connecting the electrode terminal to the electrode assembly and the battery's current collector, the input or output of the battery cell's electrical energy can be achieved. In order to reduce the difficulty of assembling the electrode terminal and improve the assembly stability of the electrode terminal, in the related art, the electrode terminal is provided with a pole and a rivet block, the pole is inserted into the mounting hole on the shell, and the pole and the electrode assembly are connected to each other, the rivet block is located on the outside of the shell, and the pole is riveted to the rivet block to achieve the assembly of the electrode terminal on the shell, and the input or output of the battery cell's electrical energy can be achieved by welding the rivet block and the battery's current collector to each other. However, in battery cells of this structure, in order to reduce the risk of welding through when the rivet block and the collector component are welded to each other, the thickness of the rivet block is usually made larger. However, the rivet block is arranged on the outside of the outer shell. After the battery cells are assembled into groups, the area on the outside of the battery cells where the rivet block protrudes will be wasted and cannot be effectively utilized, resulting in low space utilization of the battery cells after assembly, which is not conducive to improving the energy density of the battery.

[0106] Based on the above considerations, in order to solve the problem of low space utilization of battery cells after being assembled into groups, an embodiment of the present application provides a battery cell, which includes a shell, an electrode assembly and an electrode terminal. The shell has a wall portion, and the wall portion is provided with a mounting hole, and the mounting hole penetrates the wall portion along the thickness direction of the wall portion. The electrode assembly is accommodated in the shell. The electrode terminal includes a pole and a connector, the pole is inserted into the mounting hole, the pole is electrically connected to the electrode assembly, and along the thickness direction of the wall portion, the connector is located on the side of the wall portion away from the electrode assembly, and the connector is connected to the pole. The connector includes a first material layer and a second material layer stacked along the thickness direction of the wall portion, the first material layer is located on the side of the second material layer away from the electrode assembly, the first material layer is electrically connected to the pole and is used to connect to the current collector, and the melting point of the second material layer is higher than the melting point of the first material layer.

[0107] In a battery cell of this structure, the electrode terminal includes a pole and a connector, the pole is inserted into the mounting hole, and the connector is located on the side of the wall away from the electrode assembly and is connected to the pole, so as to realize the assembly of the electrode terminal on the wall, by setting the connector as a first material layer and a second material layer stacked along the thickness direction of the wall, the second material layer is located on the side of the first material layer facing the electrode assembly, so that the second material layer is located between the wall and the first material layer, and the melting point of the second material layer is greater than the melting point of the first material layer, so that the second material layer can play a certain separation and barrier role when the first material layer is welded and connected to the collector component for assembly, so as to reduce the risk of the connector being welded through and affecting other components, thereby eliminating the need to reduce the risk of the connector being welded through by increasing the thickness of the first material layer. The battery cell adopting this structure can optimize the thickness of the first material layer while reducing the risk of the connector being welded through, so as to reduce the space occupied by the connector in the thickness direction of the wall, thereby effectively improving the space utilization rate of the battery cell after assembly into groups, which is beneficial to improving the energy density of the battery having such a battery cell.

[0108] The battery cells disclosed in the embodiments of the present application can be used, but not limited to, in electrical devices such as vehicles, ships or aircraft. A power supply system comprising the battery cells and batteries disclosed in the present application can be used to form the electrical device, which is helpful to alleviate the problem of low space utilization of the battery cells after assembly, so as to improve the energy density of the battery.

[0109] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0110] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device in an embodiment of the present application.

[0111] Please refer to Figure 1 , Figure 1Schematic structural diagram of vehicle 1000 provided by some embodiments of the present application. Vehicle 1000 can be a fuel vehicle, a gas vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle, an extended-range vehicle, etc. A battery 100 is disposed inside vehicle 1000. The battery 100 can be disposed at the bottom of vehicle 1000, or at the head of vehicle 1000, or at the tail of vehicle 1000. The battery 100 can be used to supply power to vehicle 1000. For example, the battery 100 can be used as the operating power source or the power source for use of vehicle 1000. Vehicle 1000 can also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to supply power to the motor 300. For example, it is used for the working power requirements during the start, navigation, and driving of vehicle 1000.

[0112] In some embodiments of the present application, the battery 100 can not only be used as the operating power source or the power source for use of vehicle 1000, but also be used as the driving power source of vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for vehicle 1000.

[0113] Please refer to Figure 2 and Figure 3 , Figure 2 Exploded view of the structure of battery 100 provided by some embodiments of the present application, Figure 3 Schematic structural diagram of battery cell 20 provided by some embodiments of the present application. The battery 100 includes a box body 10 and battery cells 20. The battery cells 20 are used to be accommodated in the box body 10.

[0114] Among them, the box body 10 is used to provide an assembly space for the battery cells 20, and the box body 10 can adopt various structures. In some embodiments, the box body 10 can include a first box body 11 and a second box body 12. The first box body 11 and the second box body 12 cover each other, and the first box body 11 and the second box body 12 jointly define an assembly space for accommodating the battery cells 20. The second box body 12 can be a hollow structure with one end open, and the first box body 11 can be a plate-like structure. The first box body 11 covers the open side of the second box body 12 so that the first box body 11 and the second box body 12 jointly define the assembly space; the first box body 11 and the second box body 12 can also both be hollow structures with one side open, and the open side of the first box body 11 covers the open side of the second box body 12.

[0115] Of course, the box body 10 formed by the first box body 11 and the second box body 12 can have various shapes, such as a cylinder, a cuboid, or a cube, etc. Exemplarily, in Figure 2 it is, the shape of the box body 10 is a cuboid.

[0116] In the battery 100, the battery cells 20 disposed in the box body 10 may be one or more. When there are multiple battery cells 20 disposed in the box body 10, the multiple battery cells 20 may be connected in series, in parallel, or in a series-parallel combination. A series-parallel combination means that there are both series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 can be directly connected in series, in parallel, or in a series-parallel combination together, and then the whole formed by the multiple battery cells 20 is accommodated in the box body 10. Of course, the battery 100 can also be such that multiple battery cells 20 are first connected in series, in parallel, or in a series-parallel combination to form a battery module, and then multiple battery modules are connected in series, in parallel, or in a series-parallel combination to form a whole, and the whole is accommodated in the box body 10.

[0117] In some embodiments, the battery 100 may further include other structures. For example, the battery 100 may further include a busbar component for connecting the multiple battery cells 20 to achieve electrical connection among the multiple battery cells 20. The busbar component functions to connect the multiple battery cells 20 in series, in parallel, or in a series-parallel combination, and the material of the busbar component may be copper, iron, aluminum, or aluminum alloy, etc.

[0118] Among them, each battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 can be in the shape of a cuboid, a cylinder, a prism, or other shapes, etc. Exemplarily, in Figure 3 the battery cell 20 has a cuboid structure.

[0119] According to some embodiments of the present application, referring to Figure 3 and further referring to Figure 4 、 Figure 5 and Figure 6 shown, Figure 4 is an exploded view of the structure of the battery cell 20 provided in some embodiments of the present application, Figure 5 is a partial cross-sectional view of the battery cell 20 provided in some embodiments of the present application, Figure 6A cross-sectional view of an electrode terminal 23 of a battery cell 20 provided in some embodiments of the present application. The present application provides a battery cell 20, which includes a shell 21, an electrode assembly 22 and an electrode terminal 23. The shell 21 has a wall portion 211, and the wall portion 211 is provided with a mounting hole 2111, and the mounting hole 2111 penetrates the wall portion 211 along the thickness direction X of the wall portion. The electrode assembly 22 is accommodated in the shell 21. The electrode terminal 23 includes a pole 231 and a connector 232, the pole 231 is penetrated in the mounting hole 2111, the pole 231 is electrically connected to the electrode assembly 22, and along the thickness direction X of the wall portion, the connector 232 is located on the side of the wall portion 211 away from the electrode assembly 22, and the connector 232 is connected to the pole 231. The connecting member 232 includes a first material layer 2321 and a second material layer 2322 stacked along the thickness direction X of the wall portion. The first material layer 2321 is located on the side of the second material layer 2322 away from the electrode assembly 22. The first material layer 2321 is electrically connected to the pole 231 and is used to connect to the busbar component. The melting point of the second material layer 2322 is higher than the melting point of the first material layer 2321.

[0120] The housing 21 can also be used to contain electrolytes, such as electrolytes. The housing 21 can be in various structural forms. The housing 21 can also be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc.

[0121] In some embodiments, the housing 21 may include a shell 212 and an end cap 213, wherein a receiving cavity is formed inside the shell 212, and the receiving cavity has an opening 2121, that is, the shell 212 is a hollow structure with one end open, and the end cap 213 covers the opening 2121 of the shell 212 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 22 and the electrolyte.

[0122] Optionally, the wall portion 211 for mounting the electrode terminal 23 and provided with the mounting hole 2111 may be the end cover 213, or may be one of the multiple walls of the housing 212. Figure 3 and Figure 4 In the embodiment, the wall portion 211 is the end cover 213 of the shell 21. Of course, in other embodiments, the wall portion 211 can also be the bottom wall of the shell 212 arranged opposite to the end cover 213 in the thickness direction X of the wall portion, or the side wall adjacent to and abutting against the end cover 213.

[0123] When assembling the battery cell 20 , the electrode assembly 22 may be placed in the housing 212 first, and the housing 212 may be filled with electrolyte. The end cap 213 may then be placed on the opening 2121 of the housing 212 to seal the opening 2121 of the housing 212 .

[0124] Among them, the mounting hole 2111 penetrates through the wall portion 211 along the thickness direction X of the wall portion, that is to say, the mounting hole 2111 extends along the thickness direction X of the wall portion and penetrates through the surfaces on both sides of the wall portion 211.

[0125] The housing 212 can be of various shapes, such as a cylinder, a cuboid, etc. The shape of the housing 212 can be determined according to the specific shape of the electrode assembly 22. For example, if the electrode assembly 22 is a cylinder structure, the housing 212 can be selected as a cylinder structure; if the electrode assembly 22 is a cuboid structure, the housing 212 can be selected as a cuboid structure. Of course, the end cap 213 can also be of various structures. For example, the end cap 213 is a plate-like structure or a hollow structure with one end open, etc. Exemplarily, in Figure 4 it, the housing 212 is a cuboid structure and the end cap 213 is a plate-like structure.

[0126] It can be understood that the outer shell 21 is not limited to the above structure. The outer shell 21 can also be other structures. For example, the outer shell 21 includes a housing 212 and two end caps 213. The housing 212 is a hollow structure with openings 2121 on opposite sides. One end cap 213 is correspondingly closed at one opening 2121 of the housing 212 to form a sealed connection to form a sealed space for accommodating the electrode assembly 22 and the electrolyte.

[0127] The electrode assembly 22 is a component in the battery cell 20 where an electrochemical reaction occurs. The structure of the electrode assembly 22 can be various. For example, the electrode assembly 22 can be a wound structure formed by winding a positive electrode sheet, a separator, and a negative electrode sheet, or a stacked structure formed by stacking a positive electrode sheet, a separator, and a negative electrode sheet.

[0128] Exemplarily, the separator is a separator film, and the main material of the separator film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride.

[0129] Among them, the electrode assembly 22 is formed with a tab 221 at one end close to the wall portion 211 in the thickness direction X of the wall portion. The tab 221 is used to input or output the positive or negative electrode of the electrode assembly 22. The tab 221 is used to connect to the electrode terminal 23 to achieve electrical connection between the electrode assembly 22 and the electrode terminal 23. It should be noted that the tab 221 of the electrode assembly 22 is a component formed by laminating and connecting the regions on the positive electrode sheet where the positive electrode active material layer is not coated or the regions on the negative electrode sheet where the negative electrode active material layer is not coated. If the tab 221 is used to output the positive electrode of the electrode assembly 22, the tab 221 is a component formed by laminating and connecting the regions on the positive electrode sheet where the positive electrode active material layer is not coated; if the tab 221 is used to output the negative electrode of the electrode assembly 22, the tab 221 is a component formed by laminating and connecting the regions on the negative electrode sheet where the negative electrode active material layer is not coated.

[0130] Exemplarily, the material of the tab 221 may be copper or aluminum.

[0131] Optionally, the number of electrode assemblies 22 contained in the housing 21 may be one or more. Figure 4 In the embodiment, the outer shell 21 of the battery cell 20 is provided with two electrode assemblies 22, and the two electrode assemblies 22 are stacked along the thickness direction thereof, that is, the two electrode assemblies 22 are stacked along the thickness direction of the battery cell 20. Of course, in other embodiments, the electrode assemblies 22 accommodated in the outer shell 21 can be one, three, four, five, six, seven or eight, etc.

[0132] The electrode terminal 23 serves to output or input the electric energy of the battery cell 20 . One end of the electrode terminal 23 is used to connect to the tab 221 of the electrode assembly 22 , and the other end is used to connect to the busbar component to realize the input or output of the electric energy of the battery cell 20 .

[0133] The electrode terminal 23 includes a pole 231 and a connector 232 . The pole 231 and the connector 232 are interconnected. The pole 231 is used to be electrically connected to the electrode assembly 22 , and the connector 232 is used to be electrically connected to the busbar component to achieve electrical connection between the electrode assembly 22 and the busbar component, thereby being able to output or input electrical energy of the battery cell 20 .

[0134] The pole 231 is passed through the mounting hole 2111, that is, the pole 231 passes through the mounting hole 2111, and the mounting holes 2111 are extended from both ends of the pole 231 in the thickness direction X of the wall, so that part of the pole 231 is located in the mounting hole 2111, so that the pole 231 can be connected to the electrode assembly 22 located inside the shell 21, and can also be connected to the connecting piece 232 located on the side of the wall 211 away from the electrode assembly 22, so that the pole 231 is fastened to the wall 211.

[0135] exist Figure 5 In the embodiment, part of the pole 231 abuts against the side of the wall 211 facing the electrode assembly 22, that is, the pole 231 has a part located on the side of the wall 211 facing the electrode assembly 22, and the part overlaps with the wall 211 in the thickness direction X of the wall, so that the pole 231 can abut against the side of the wall 211 facing the electrode assembly 22 along the thickness direction X of the wall, so that the pole 231 can cooperate with the connector 232 located on the side of the wall 211 away from the electrode assembly 22 to clamp the wall 211, so as to assemble the electrode terminal 23 to the wall 211. It should be noted that the pole 231 can be directly abutted against the side of the wall 211 facing the electrode assembly 22, or it can be indirectly abutted against the side of the wall 211 facing the electrode assembly 22 through other components.

[0136] The terminal post 231 serves to connect the electrode assembly 22 to achieve electrical connection between the electrode assembly 22 and the electrode terminal 23. Optionally, the terminal post 231 can be directly connected to the tab 221 of the electrode assembly 22, or indirectly connected to the tab 221 of the electrode assembly 22 through other components.

[0137] In some embodiments, as shown in Figure 4 the battery cell 20 may further include a current collector member 24. The current collector member 24 is disposed within the housing 21. The current collector member 24 connects the terminal post 231 of the electrode terminal 23 and the tab 221 of the electrode assembly 22 to achieve electrical connection between the electrode assembly 22 and the electrode terminal 23.

[0138] Exemplarily, the current collector member 24 is welded to the terminal post 231 and welded to the tab 221. Of course, in other embodiments, the current collector member 24 can also be in abutting contact or adhered to the terminal post 231, and similarly, the current collector member 24 can also be in abutting contact or adhered to the tab 221.

[0139] The current collector member 24 serves to connect the terminal post 231 of the electrode terminal 23 and the tab 221 of the electrode assembly 22. The material of the current collector member 24 can be various. For example, the material of the current collector member 24 can be copper, iron, aluminum, steel, aluminum alloy, etc.

[0140] In Figure 4 the battery cell 20 includes two electrode terminals 23 and two current collector members 24. Correspondingly, each electrode assembly 22 has two tabs 221, and the polarities of the two tabs 221 are opposite. The two electrode terminals 23 are respectively electrically connected to the two tabs 221 of the electrode assembly 22 through the two current collector members 24 to achieve input or output of the positive and negative electrodes of the battery cell 20.

[0141] Optionally, both of the two electrode terminals 23 are mounted on the wall portion 211. Each electrode terminal 23 is electrically connected to one tab 221 of the electrode assembly 22 to output the positive and negative electrodes of the battery cell 20. Of course, in other embodiments, the two electrode terminals 23 can also be mounted on different walls of the housing 21. For example, in some embodiments, the two electrode terminals 23 can be respectively disposed on two opposite walls of the housing 21 in the thickness direction X of the wall portion.

[0142] The connecting member 232 is located on the side of the wall portion 211 facing away from the electrode assembly 22. The connecting member 232 is connected to the terminal post 231. That is to say, the connecting member 232 is located outside the housing 21, and the connecting member 232 is connected to a portion of the terminal post 231 extending out of the mounting hole 2111 and facing away from the electrode assembly 22, so that the connecting member 232 and the terminal post 231 can cooperate to clamp the wall portion 211, thereby achieving the assembly of the electrode terminal 23 to the wall portion 211.

[0143] Exemplarily, one end of the terminal post 231 away from the electrode assembly 22 in the thickness direction X of the wall portion is riveted to the connecting member 232 to connect the terminal post 231 and the connecting member 232. Of course, in other embodiments, the terminal post 231 and the connecting member 232 may also be connected to each other by structures such as welding connection, snap connection or bolt connection.

[0144] The connecting member 232 includes a first material layer 2321 and a second material layer 2322. The connection structure between the first material layer 2321 and the second material layer 2322 can be various, such as bonding, bolt screwing, composite connection or welding connection, etc. Exemplarily, in the embodiment of the present application, the first material layer 2321 and the second material layer 2322 are in a composite connection, such as hot pressing or cold pressing, etc.

[0145] The first material layer 2321 is located on the side of the second material layer 2322 away from the electrode assembly 22, that is to say, the second material layer 2322 is located between the first material layer 2321 and the wall portion 211 in the thickness direction X of the wall portion.

[0146] The first material layer 2321 is used for welding connection with the bus bar component. That is to say, the first material layer 2321 functions to be welded to the bus bar component of the battery 100 to enable the battery cell 20 to be electrically connected to the bus bar component, so that the bus bar component can be electrically connected to the terminal post 231 through the first material layer 2321. Exemplarily, the first material layer 2321 is welded to the bus bar component on the side away from the electrode assembly 22 in the thickness direction X of the wall portion.

[0147] In some embodiments, referring to Figure 3 and Figure 4 as shown, the battery cell 20 may further include a pressure relief mechanism 25. The pressure relief mechanism 25 is arranged on the outer shell 21 and is used for relieving the pressure inside the battery cell 20 when the internal pressure or temperature of the battery cell 20 reaches a predetermined value.

[0148] Optionally, the pressure relief mechanism 25 may be arranged on the end cover 213 of the outer shell 21 or on the housing 212 of the outer shell 21. Exemplarily, in Figure 3 and Figure 4 the pressure relief mechanism 25 is arranged on the end cover 213.

[0149] Similarly, the pressure relief mechanism 25 and the outer shell 21 may be of an integrally formed structure or a separately arranged structure. Exemplarily, in Figure 4In the embodiment, the pressure relief mechanism 25 and the housing 21 are of a split structure, and the pressure relief mechanism 25 can be connected to the housing 21 by welding or the like, and correspondingly, the pressure relief mechanism 25 can be a pressure relief component such as an explosion-proof valve, an explosion-proof disk, an air valve, a pressure relief valve or a safety valve. Of course, in other embodiments, the pressure relief mechanism 25 and the housing 21 can also be an integrally formed structure, and the pressure relief mechanism 25 is an area on the housing 21 where a weak structure is formed, for example, an area on the housing 21 where a notch groove is provided.

[0150] In this embodiment, the electrode terminal 23 includes a pole 231 and a connecting member 232, the pole 231 is inserted into the mounting hole 2111, and the connecting member 232 is located on the side of the wall portion 211 away from the electrode assembly 22 and is connected to the pole 231, so that the electrode terminal 23 is assembled on the wall portion 211, and the connecting member 232 is set as a first material layer 2321 and a second material layer 2322 stacked along the thickness direction X of the wall portion, and the second material layer 2322 is located on the side of the first material layer 2321 facing the electrode assembly 22, so that the second material layer 2322 is located between the wall portion 211 and the first material layer 2321, and the melting point of the second material layer 2322 is greater than the melting point of the first material layer 2321. The second material layer 2322 can play a certain role in separation and barrier when the first material layer 2321 is welded and connected to the convergence component for assembly, so as to reduce the risk of the connector 232 being welded through and affecting other components, thereby eliminating the need to increase the thickness of the first material layer 2321 to reduce the risk of the connector 232 being welded through. The battery cell 20 with this structure can optimize the thickness of the first material layer 2321 while reducing the risk of the connector 232 being welded through, so as to reduce the space occupied by the connector 232 in the thickness direction X of the wall, thereby effectively improving the space utilization of the battery cell 20 after assembly into groups, which is beneficial to improving the energy density of the battery 100 having such a battery cell 20.

[0151] According to some embodiments of the present application, the melting point of the first material layer 2321 is MP1, and the melting point of the second material layer 2322 is MP2, satisfying MP2-MP1≥200°C.

[0152] Among them, MP2-MP1≥200℃, that is, the difference between the melting point of the second material layer 2322 and the melting point of the first material layer 2321 is greater than or equal to 200℃, which can be 200℃, 210℃, 220℃, 250℃, 280℃, 300℃, 350℃, 400℃, 450℃, 500℃, 550℃, 600℃, 650℃ or 700℃, etc.

[0153] Exemplarily, the material of the first material layer 2321 and the material of the conduit component are aluminum or aluminum alloy, etc. Correspondingly, the material of the second material layer 2322 can be steel, copper, iron or silver, etc.

[0154] In this embodiment, by setting the melting point of the second material layer 2322 to be greater than or equal to 200 degrees Celsius higher than the melting point of the first material layer 2321, the phenomenon that the second material layer 2322 is melted during the assembly of the first material layer 2321 and the bus bar component by welding connection can be further alleviated, so that the separation effect and barrier effect of the second material layer 2322 can be further improved, and the risk that the connector 232 is welded through can be further reduced.

[0155] According to some embodiments of the present application, as shown in Figure 6 along the thickness direction X of the wall portion, the thickness of the first material layer 2321 is D1, and the thickness of the second material layer 2322 is D2, satisfying 0.1 ≤ D2 / D1 ≤ 0.25.

[0156] Exemplarily, the ratio of the thickness D2 of the second material layer 2322 to the thickness D1 of the first material layer 2321 can be 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24 or 0.25, etc.

[0157] In this embodiment, by setting the thickness of the second material layer 2322 to be greater than or equal to 0.1 times the thickness of the first material layer 2321, the second material layer 2322 has sufficient thickness to separate and block during the assembly of the first material layer 2321 and the bus bar component by welding connection, so as to alleviate the phenomenon that the second material layer 2322 is welded through. By setting the thickness of the second material layer 2322 to be less than or equal to 0.25 times the thickness of the first material layer 2321, the phenomenon of excessive waste of the thickness of the second material layer 2322 can be reduced, which is beneficial to reducing the manufacturing cost of the connector 232, and can save the space occupied by the second material layer 2322 in the thickness direction X of the wall portion, which is beneficial to improving the space utilization rate after the battery cells 20 are assembled into a group.

[0158] In some embodiments, the first material layer 2321 and the second material layer 2322 are connected in a composite manner.

[0159] Among them, the ways in which the first material layer 2321 and the second material layer 2322 are connected in a composite manner can be various. For example, the first material layer 2321 and the second material layer 2322 can be connected by composite processes such as hot pressing or cold pressing. Of course, in other embodiments, the first material layer 2321 and the second material layer 2322 can also be connected by bonding, clamping or welding.

[0160] In this embodiment, a composite connection structure is adopted to connect the first material layer 2321 and the second material layer 2322, which can effectively improve the structural strength and connection stability of the first material layer 2321 and the second material layer 2322, and is beneficial to reducing the risk of mutual detachment between the first material layer 2321 and the second material layer 2322.

[0161] In some embodiments, the material of the first material layer 2321 is aluminum, and the material of the second material layer 2322 is steel. It should be noted that when the material of the first material layer 2321 is aluminum, the material of the second material layer 2322 can also be copper, iron, silver, etc.

[0162] In this embodiment, by setting the material of the first material layer 2321 as aluminum and correspondingly setting the material of the second material layer 2322 as steel, on the one hand, the manufacturing cost of the connector 232 can be reduced, and on the other hand, the melting point of the second material layer 2322 is much higher than that of the first material layer 2321, so that the second material layer 2322 has a good separation and blocking effect during the welding connection and assembly of the first material layer 2321 and the busbar component, thereby effectively reducing the risk of the connector 232 being welded through.

[0163] According to some embodiments of the present application, referring to Figure 5 and Figure 6 As shown, the terminal post 231 may include a body portion 2311 and an abutting portion 2312. The body portion 2311 is inserted through the mounting hole 2111 along the thickness direction X of the wall portion, and the body portion 2311 is connected to the connector 232. The abutting portion 2312 abuts against the side of the wall portion 211 facing the electrode assembly 22, and the abutting portion 2312 and the connector 232 cooperate to clamp the wall portion 211 to fasten the electrode terminal 23 to the wall portion 211.

[0164] Among them, the body portion 2311 of the terminal post 231 is a structure inserted into the mounting hole 2111 along the thickness direction X of the wall portion, and both ends of the body portion 2311 in the thickness direction X of the wall portion extend out of both ends of the mounting hole 2111, so that both ends of the body portion 2311 can be respectively connected to the connector 232 and the abutting portion 2312.

[0165] Optionally, the connection structure between the connector 232 and the body portion 2311 can be various, such as welding, riveting, clamping or bolt connection, etc.

[0166] The abutting portion 2312 abuts against the side of the wall portion 211 facing the electrode assembly 22. The abutting portion 2312 and the connecting member 232 cooperate to clamp the wall portion 211. That is to say, the abutting portion 2312 is located on the side of the wall portion 211 facing the electrode assembly 22 in the thickness direction X of the wall portion, and at least a part of the abutting portion 2312 overlaps with the wall portion 211 in the thickness direction X of the wall portion, so that the abutting portion 2312 can cooperate with the connecting member 232 to clamp the wall portion 211.

[0167] It should be noted that the abutting portion 2312 can directly abut against the side of the wall portion 211 facing the electrode assembly 22, or can indirectly abut against the side of the wall portion 211 facing the electrode assembly 22 through other components. Exemplarily, in Figure 5 , the electrode terminal 23 is a structure insulated and mounted on the wall portion 211, and a second insulating member 27 is provided between the abutting portion 2312 of the pole column 231 and the wall portion 211, so that the abutting portion 2312 indirectly abuts against the side of the wall portion 211 facing the electrode assembly 22 through the second insulating member 27. Refer to Figure 7 , Figure 7 FIG. is a partial cross-sectional view of the battery cell 20 provided by some other embodiments of the present application. The electrode terminal 23 is a structure electrically connected to the wall portion 211 of the housing 21, so that the abutting portion 2312 of the pole column 231 directly abuts against the side of the wall portion 211 facing the electrode assembly 22.

[0168] Exemplarily, in Figure 6 , the body portion 2311 and the abutting portion 2312 are integrally formed structures. That is to say, the body portion 2311 and the abutting portion 2312 are an integral structure, and the body portion 2311 and the abutting portion 2312 can be made by integral forming processes such as casting, stamping or milling. Of course, in other embodiments, the body portion 2311 and the abutting portion 2312 can also be separately provided structures. That is to say, the body portion 2311 and the abutting portion 2312 can also be a split structure, and the abutting portion 2312 can be connected to one end of the body portion 2311 facing the electrode assembly 22 in the thickness direction X of the wall portion by welding, clamping or bolt screwing.

[0169] In this embodiment, the pole column 231 is provided with a body portion 2311 penetrating through the mounting hole 2111, and the two ends of the body portion 2311 in the thickness direction X of the wall portion are respectively connected with an abutting portion 2312 and a connecting member 232, so that the abutting portion 2312 and the connecting member 232 located on both sides of the wall portion 211 in the thickness direction X of the wall portion can cooperate to clamp the wall portion 211, thereby realizing the assembly of the electrode terminal 23 on the wall portion 211, with a simple structure and convenient assembly.

[0170] In some embodiments, refer to Figure 6As shown, the body portion 2311 is riveted to the first material layer 2321.

[0171] Wherein, a channel for the body portion 2311 to pass through in the thickness direction X of the wall portion is provided on the second material layer 2322, and a riveting hole 2321a is provided on the first material layer 2321. The riveting hole 2321a penetrates through both sides of the first material layer 2321 in the thickness direction X of the wall portion, and the riveting hole 2321a is communicated with the channel of the second material layer 2322. One end of the body portion 2311 away from the electrode assembly 22 in the thickness direction X of the wall portion is inserted into the riveting hole 2321a and riveted to the first material layer 2321.

[0172] In this embodiment, by riveting the body portion 2311 of the pole column 231 to the first material layer 2321 of the connecting member 232, the assembly connection between the pole column 231 and the connecting member 232 is realized. The structure is simple, convenient for assembly, and has high structural stability, which is beneficial to reducing the phenomenon of connection failure between the pole column 231 and the connecting member 232.

[0173] According to some embodiments of the present application, refer to Figure 5 As shown, the electrode terminal 23 is insulatingly installed on the wall portion 211. That is to say, no electrical connection is formed between the electrode terminal 23 and the housing 21.

[0174] In this embodiment, by insulatingly installing the electrode terminal 23 on the wall portion 211, no electrical connection is formed between the electrode terminal 23 and the wall portion 211. On the one hand, it is convenient for the electrode terminal 23 to input or output the electric energy of the battery cell 20, and on the other hand, it can reduce the short - circuit risk of the battery cell 20.

[0175] In some embodiments, please continue to refer to Figure 5 As shown, the battery cell 20 may further include a first insulating member 26 and a second insulating member 27. Along the thickness direction X of the wall portion, at least a part of the first insulating member 26 is disposed between the connecting member 232 and the wall portion 211, and the first insulating member 26 is configured to insulate and isolate the connecting member 232 and the wall portion 211. Along the thickness direction X of the wall portion, at least a part of the second insulating member 27 is disposed between the pole column 231 and the wall portion 211, and the second insulating member 27 is configured to insulate and isolate the pole column 231 and the wall portion 211.

[0176] Optionally, the first insulating member 26 functions to insulate and isolate the connecting member 232 and the wall portion 211, and the material of the first insulating member 26 can be various, such as rubber, silicone or plastic, etc. Similarly, the second insulating member 27 functions to insulate and isolate the pole column 231 and the wall portion 211, and the material of the second insulating member 27 can also be various, such as rubber, silicone or plastic, etc.

[0177] In this embodiment, by providing a first insulating member 26 between the connecting member 232 and the wall portion 211, the first insulating member 26 can insulatively isolate the wall portion 211 and the connecting member 232, thereby reducing the risk of short circuit between the wall portion 211 and the connecting member 232. Correspondingly, by providing a second insulating member 27 between the pole column 231 and the wall portion 211, the second insulating member 27 can insulatively isolate the wall portion 211 and the pole column 231, thereby reducing the risk of short circuit between the wall portion 211 and the pole column 231. Furthermore, by providing the first insulating member 26 and the second insulating member 27 on both sides of the wall portion 211 respectively, the electrode terminal 23 is insulatively mounted on the wall portion 211.

[0178] In some embodiments, please continue to refer to Figure 5 As shown, the battery cell 20 may further include a seal member 28. The seal member 28 is disposed between the wall portion 211 and the pole column 231, and at least a part of the seal member 28 is located within the mounting hole 2111. The seal member 28 is configured to seal the gap between the pole column 231 and the hole wall surface of the mounting hole 2111.

[0179] Among them, in an embodiment where the pole column 231 includes a body portion 2311 and an abutting portion 2312, the seal member 28 is sleeved on the outer side of the body portion 2311, and the seal member 28 is located between the body portion 2311 and the hole wall surface of the mounting hole 2111, so that the seal member 28 can seal the gap between the body portion 2311 and the hole wall surface of the mounting hole 2111.

[0180] At least a part of the seal member 28 is located within the mounting hole 2111, that is to say, the seal member 28 may be entirely located within the mounting hole 2111, or only partially located within the mounting hole 2111. In Figure 5 it, a part of the seal member 28 is located within the mounting hole 2111, and the other part is located between the wall portion 211 and the abutting portion 2312 of the pole column 231.

[0181] Exemplarily, the material of the seal member 28 may be rubber, silica gel, plastic, or the like.

[0182] In this embodiment, by providing the seal member 28 between the wall portion 211 and the pole column 231 of the electrode terminal 23, and at least a part of the seal member 28 is located within the mounting hole 2111, the seal member 28 can seal the gap between the pole column 231 and the hole wall surface of the mounting hole 2111, thereby effectively reducing the phenomenon that the electrolyte inside the battery cell 20 overflows from the mounting hole 2111, and improving the use stability and reliability of the battery cell 20.

[0183] In some embodiments, please continue to refer to Figure 5As shown, along the thickness direction X of the wall portion, a receiving groove 2112 is provided on the side of the wall portion 211 facing away from the electrode assembly 22. The mounting hole 2111 is provided on the bottom surface of the receiving groove 2112, and at least a part of the first insulating member 26 is received in the receiving groove 2112.

[0184] Among them, the mounting hole 2111 is provided on the bottom surface of the receiving groove 2112. That is to say, the mounting hole 2111 is a structure that penetrates the bottom surface of the receiving groove 2112 along the thickness direction X of the wall portion.

[0185] Exemplarily, a part of the first insulating member 26 is received in the receiving groove 2112. Of course, in other embodiments, the first insulating member 26 may also be entirely located in the receiving groove 2112.

[0186] In this embodiment, by providing a receiving groove 2112 for receiving the first insulating member 26 on the side of the wall portion 211 facing away from the electrode assembly 22, it is convenient to assemble the first insulating member 26 between the connecting member 232 and the wall portion 211, which can play a role in assembling and positioning the first insulating member 26, is beneficial to reducing the assembly difficulty of the first insulating member 26, and can play a certain protective role for the first insulating member 26 to reduce the occurrence of wear or damage of the first insulating member 26 during use.

[0187] According to some embodiments of the present application, see Figure 7 As shown, the second material layer 2322 is welded to the wall portion 211.

[0188] Among them, the second material layer 2322 and the wall portion 211 are welded to each other, so that the second material layer 2322 of the connecting member 232 is a structure that is electrically connected to the wall portion 211, so as to form an electrical connection between the electrode terminal 23 and the housing 21.

[0189] It should be noted that among the two electrode terminals 23 of the battery cell 20, one electrode terminal 23 is a structure electrically connected to the housing 21, and the other electrode terminal 23 is a structure insulated from the housing 21 (as Figure 5 shown), of course, the battery cell 20 may also be a structure in which both electrode terminals 23 are insulated from the housing 21.

[0190] In this embodiment, by welding the second material layer 2322 of the connecting member 232 to the wall portion 211, the connecting member 232 of the electrode terminal 23 is a structure electrically connected to the wall portion 211 of the housing 21, so as to output or input the electric energy of the battery cell 20. The battery cell 20 with this structure does not need to be provided with an insulating component for insulating isolation between the connecting member 232 and the wall portion 211, which is beneficial to reducing the manufacturing cost and assembly difficulty of the battery cell 20.

[0191] In some embodiments, please continue to refer to Figure 7 As shown, the second material layer 2322 is welded to the wall portion 211 to form a weld mark (not shown in the figure), and the weld mark surrounds the outside of the mounting hole 2111. That is to say, the weld mark formed by welding the second material layer 2322 and the wall portion 211 to each other is an annular structure that surrounds the mounting hole 2111 and is located between the second material layer 2322 and the wall portion 211.

[0192] In this embodiment, by setting the weld mark formed by welding the second material layer 2322 and the wall portion 211 to each other to be a structure that surrounds the outside of the mounting hole 2111, the weld mark formed by welding the second material layer 2322 and the wall portion 211 to each other surrounds the mounting hole 2111. Thus, the gap between the connecting member 232 and the wall portion 211 can be sealed through the weld mark, and further, there is no need to provide a sealing member for sealing between the pole 231 and the hole wall surface of the mounting hole 2111, which is beneficial to reducing the manufacturing cost and assembly difficulty of the battery cell 20.

[0193] In some embodiments, the material of the second material layer 2322 is the same as the material of the wall portion 211.

[0194] It should be noted that the material of the second material layer 2322 being the same as the material of the wall portion 211 means that the main components of the second material layer 2322 and the wall portion 211 are the same. For example, if both the second material layer 2322 and the wall portion 211 are single materials, then both the second material layer 2322 and the wall portion 211 are composed of the same metal elements; if the second material layer 2322 and the wall portion 211 are alloy materials or mixed materials, such as steel, etc., then the material of the second material layer 2322 being the same as the material of the wall portion 211 means that the main components of the second material layer 2322 and the wall portion 211 are the same. If the second material layer 2322 and the wall portion 211 only have different contents of components, they are also the same material.

[0195] In this embodiment, by setting the material of the second material layer 2322 to be the same as the material of the wall portion 211, a structure in which the second material and the wall portion 211 are welded with the same material can be realized. On the one hand, the welding difficulty between the second material layer 2322 and the wall portion 211 can be reduced, and on the other hand, phenomena such as virtual welding or welding failure between the second material layer 2322 and the wall portion 211 can be reduced, which is beneficial to improving the welding quality between the second material layer 2322 and the wall portion 211.

[0196] In some embodiments, refer to Figure 7As shown, along the thickness direction X of the wall portion, a receiving groove 2112 is provided on the side of the wall portion 211 facing away from the electrode assembly 22. The mounting hole 2111 is provided on the bottom surface of the receiving groove 2112. At least a part of the connecting member 232 is received in the receiving groove 2112, and the second material layer 2322 is welded to the bottom surface of the receiving groove 2112.

[0197] Among them, the mounting hole 2111 is provided on the bottom surface of the receiving groove 2112, that is to say, the mounting hole 2111 is a structure that penetrates the bottom surface of the receiving groove 2112 along the thickness direction X of the wall portion.

[0198] Exemplarily, a part of the connecting member 232 is received in the receiving groove 2112, and the second material layer 2322 is located between the first material layer 2321 and the bottom surface of the receiving groove 2112 in the thickness direction X of the wall portion. Of course, in other embodiments, the connecting member 232 may also be entirely located in the receiving groove 2112.

[0199] In this embodiment, by providing a receiving groove 2112 for receiving the connecting member 232 on the side of the wall portion 211 facing away from the electrode assembly 22, on the one hand, it can play a role in assembling and positioning the connecting member 232, which is beneficial to reducing the welding difficulty between the wall portion 211 and the second material layer 2322 of the connecting member 232, and can improve the welding quality between the wall portion 211 and the second material layer 2322 of the connecting member 232. On the other hand, it can play a certain protective role for the connecting member 232 to reduce the occurrence of wear or damage of the connecting member 232 during use.

[0200] According to some embodiments of the present application, referring to Figure 3 and Figure 4 As shown, the outer shell 21 may include a housing 212 and an end cover 213. An accommodation cavity with an opening 2121 is formed inside the housing 212, and the accommodation cavity is used to accommodate the electrode assembly 22. The end cover 213 closes the opening 2121, and the end cover 213 is the wall portion 211.

[0201] Among them, the end cover 213 is the wall portion 211, that is to say, the electrode terminal 23 is installed on the end cover 213, and the mounting hole 2111 is provided on the end cover 213.

[0202] In this embodiment, by setting the wall portion 211 of the outer shell 21 as the end cover 213 for closing the opening 2121 of the housing 212, the battery cell 20 with this structure is convenient for assembling the electrode terminal 23 on the end cover 213, and is convenient for assembling and connecting the pole column 231 of the electrode terminal 23 with the electrode assembly 22, which is beneficial to reducing the assembly difficulty of the battery cell 20 to improve the production efficiency of the battery cell 20.

[0203] It should be noted that the structure of the battery cell 20 is not limited to this. In some embodiments, the battery cell 20 may also have other structures. For example, the housing 21 may include a housing body 212 and an end cap 213. The housing body 212 includes a side wall and a wall portion 211 formed integrally. The side wall surrounds the wall portion 211. Along the thickness direction X of the wall portion, one end of the side wall is connected to the wall portion 211, and the other end encloses an opening 2121. The side wall and the wall portion 211 together define a receiving cavity for receiving the electrode assembly 22, and the end cap 213 closes the opening 2121. That is to say, the wall portion 211 is the bottom wall of the housing body 212 opposite to the end cap 213 in the thickness direction X of the wall portion, that is, the electrode terminal 23 is installed on the bottom wall of the housing body 212, and the mounting hole 2111 is provided on the bottom wall of the housing body 212.

[0204] Among them, the housing body 212 includes a side wall and a wall portion 211 formed integrally, that is, the housing body 212 is processed by an integral forming process, such as an integral forming process such as stamping, casting or extrusion molding. That is to say, the side wall and the wall portion 211 of the housing body 212 are an integral structure.

[0205] In this embodiment, by setting the wall portion 211 of the housing 21 as a wall of the housing body 212 opposite to the end cap 213 in the thickness direction X of the wall portion, the battery cell 20 with this structure can make the area of the housing 21 where the electrode terminal 23 is installed away from the end cap 213, and there is no direct connection relationship between the wall portion 211 and the end cap 213, so as to relieve the force generated when the components such as the electrode terminal 23 pull or twist the wall portion 211 from acting on the end cap 213, so as to reduce the risk of connection failure between the end cap 213 and the housing body 212, and further is beneficial to reducing the risk of liquid leakage during the use of the battery cell 20.

[0206] According to some embodiments of the present application, the present application also provides a battery 100, and the battery 100 includes the battery cell 20 of any of the above solutions.

[0207] Among them, as shown in Figure 2 the battery 100 may further include a box body 10, and the battery cell 20 is received in the box body 10.

[0208] In some embodiments, the box body 10 may include a first box body 11 and a second box body 12. The first box body 11 and the second box body 12 cover each other, and the first box body 11 and the second box body 12 together define an assembly space for receiving the battery cell 20.

[0209] Optionally, the second box body 12 may be a hollow structure with one end open, and the first box body 11 may be a plate-like structure. The first box body 11 covers the open side of the second box body 12 so that the first box body 11 and the second box body 12 jointly define an assembly space; the first box body 11 and the second box body 12 may also both be hollow structures with one side open, and the open side of the first box body 11 covers the open side of the second box body 12.

[0210] Of course, the box body 10 formed by the first box body 11 and the second box body 12 can be of various shapes, such as a cylinder or a cuboid, etc. Exemplarily, in Figure 2 the box body 10 is a cuboid structure.

[0211] Optionally, the battery cells 20 disposed in the box body 10 may be one or multiple. Exemplarily, in Figure 2 the box body 10 of the battery 100 is provided with multiple battery cells 20. The multiple battery cells 20 may be connected in series, parallel, or in a mixed connection. A mixed connection means that there are both series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 can be directly connected in series, parallel, or in a mixed connection together, and then the whole formed by the multiple battery cells 20 is accommodated in the box body 10; of course, the battery 100 can also be in the form that multiple battery cells 20 are first connected in series, parallel, or in a mixed connection to form battery modules, and then the multiple battery modules are connected in series, parallel, or in a mixed connection to form a whole and are accommodated in the box body 10.

[0212] It should be noted that in some embodiments, the battery 100 may not be provided with the box body 10. The battery 100 includes multiple battery cells 20, and the battery 100 composed of the multiple battery cells 20 can be directly assembled to the electrical device to provide electrical energy for the electrical device through the multiple battery cells 20. That is to say, the box body 10 can be a part of the electrical device. Taking the vehicle 1000 as an example of the electrical device, the box body 10 can be a part of the chassis structure of the vehicle 1000. For example, a part of the box body 10 can become at least a part of the floor of the vehicle 1000, or a part of the box body 10 can become at least a part of the cross beams and longitudinal beams of the vehicle 1000.

[0213] According to some embodiments of the present application, referring to Figure 5 and Figure 7 as shown, the battery 100 further includes a busbar component (not shown in the figure). The busbar component is welded to the first material layer 2321 to electrically connect the busbar component and the pole 231.

[0214] Among them, the busbar component is welded to the first material layer 2321 of the connecting member 232 of the electrode terminal 23, so that the busbar component can be electrically connected to the electrode terminal 23, and the busbar component can be electrically connected to a plurality of battery cells 20, thereby realizing the series or parallel connection between the plurality of battery cells 20.

[0215] In this embodiment, by welding the busbar component to the first material layer 2321 of the connecting member 232, the electrical connection between the busbar component and the electrode terminal 23 is realized, so that the electrical energy of the battery cell 20 can be input or output through the busbar component. Among them, by arranging the connecting member 232 as the first material layer 2321 and the second material layer 2322 stacked along the thickness direction X of the wall portion, the second material layer 2322 is located on the side of the first material layer 2321 facing the electrode assembly 22, so that the second material layer 2322 is located between the wall portion 211 and the first material layer 2321, and the melting point of the second material layer 2322 is greater than the melting point of the first material layer 2321, so that the second material layer 2322 can play a certain role of separation and blocking during the welding connection and assembly of the first material layer 2321 and the busbar component, so as to reduce the risk that the connecting member 232 is welded through and affects other components. Therefore, there is no need to increase the thickness of the first material layer 2321 to reduce the risk of the connecting member 232 being welded through. The battery cell 20 with this structure can optimize the thickness of the first material layer 2321 while reducing the risk of the connecting member 232 being welded through, so as to reduce the space occupied by the connecting member 232 in the thickness direction X of the wall portion, and further effectively improve the space utilization rate of the battery cell 20 after being assembled into a group, which is beneficial to improving the energy density of the battery 100 with such a battery cell 20.

[0216] In some embodiments, the material of the busbar component is the same as the material of the first material layer 2321.

[0217] It should be noted that the material of the first material layer 2321 being the same as the material of the busbar component means that the main components of the first material layer 2321 and the busbar component are the same. For example, if the first material layer 2321 and the busbar component are both single materials, such as aluminum, etc., then the first material layer 2321 and the busbar component are both composed of the same metal elements; if the first material layer 2321 and the busbar component are alloy materials or mixed materials, such as aluminum alloy, etc., then the material of the first material layer 2321 being the same as the material of the busbar component means that the main components of the first material layer 2321 and the busbar component are the same. If the first material layer 2321 and the busbar component only have different contents of components, they are also of the same material.

[0218] In this embodiment, by setting the material of the bus bar component to be the same as that of the first material layer 2321, a structure in which the bus bar component and the first material layer 2321 are welded with the same material can be achieved. On the one hand, the welding difficulty between the bus bar component and the first material layer 2321 can be reduced, and on the other hand, phenomena such as virtual soldering or welding failure between the bus bar component and the first material layer 2321 can be reduced, which is beneficial to improving the welding quality between the bus bar component and the first material layer 2321.

[0219] According to some embodiments of the present application, the present application also provides an electrical device, which includes the battery cell 20 of any of the above solutions, and the battery cell 20 is used to provide electrical energy for the electrical device.

[0220] Among them, the electrical device may be any of the foregoing devices or systems that apply the battery cell 20.

[0221] According to some embodiments of the present application, refer to Figures 3 to 6As shown, the present application provides a battery cell 20, which includes a shell 21, an electrode assembly 22, an electrode terminal 23, a first insulating member 26, a second insulating member 27 and a sealing member 28. The shell 21 has a wall portion 211, and the wall portion 211 is provided with a mounting hole 2111, and the mounting hole 2111 penetrates the wall portion 211 along the thickness direction X of the wall portion. The shell 21 includes a shell 212 and an end cover 213, and the interior of the shell 212 forms a receiving cavity with an opening 2121, and the end cover 213 closes the opening 2121, and the end cover 213 is the wall portion 211. The electrode assembly 22 is accommodated in the receiving cavity. The electrode terminal 23 is insulated and installed on the wall 211. The electrode terminal 23 includes a pole 231 and a connector 232. The pole 231 includes a body 2311 and abutment 2312. The body 2311 is inserted into the mounting hole 2111 along the thickness direction X of the wall. The abutment 2312 abuts against the side of the wall 211 facing the electrode assembly 22. The abutment 2312 is electrically connected to the pole ear 221 of the electrode assembly 22. The body 2311 and the abutment 2312 are an integrally formed structure. Along the thickness direction X of the wall, the connector 232 is located on the side of the wall 211 away from the electrode assembly 22, and one end of the body 2311 away from the electrode assembly 22 is riveted to the connector 232. The connector 232 and the abutment 2312 cooperate to clamp the wall 211 to fasten the electrode terminal 23 to the wall 211. The connector 232 includes a first material layer 2321 and a second material layer 2322 which are stacked and compositely connected along the thickness direction X of the wall portion. The first material layer 2321 is located on the side of the second material layer 2322 away from the electrode assembly 22. The first material layer 2321 is electrically connected to the body 2311 of the pole 231, and the first material layer 2321 is used for welding and connection with the current collecting component. The material of the first material layer 2321 is the same as that of the current collecting component, and the melting point of the second material layer 2322 is higher than that of the first material layer 2321. The melting point of the first material layer 2321 is MP1, and the melting point of the second material layer 2322 is MP2, which satisfies MP2-MP1≥200°C. Along the thickness direction X of the wall portion, the thickness of the first material layer 2321 is D1, and the thickness of the second material layer 2322 is D2, which satisfies 0.1≤D2 / D1≤0.25. The material of the first material layer 2321 is aluminum, and the material of the second material layer 2322 is steel. Along the thickness direction X of the wall, at least a portion of the first insulating member 26 is disposed between the second material layer 2322 of the connector 232 and the wall 211, and the first insulating member 26 is configured to insulate and isolate the connector 232 from the wall 211. Along the thickness direction X of the wall, at least a portion of the second insulating member 27 is disposed between the abutting portion 2312 of the pole 231 and the wall 211, and the second insulating member 27 is configured to insulate and isolate the pole 231 from the wall 211.The seal 28 is disposed between the wall portion 211 and the terminal post 231, and at least a part of the seal 28 is located within the mounting hole 2111. The seal 28 is sleeved on the outer side of the body portion 2311 of the terminal post 231, and the seal 28 is configured to seal the gap between the terminal post 231 and the hole wall surface of the mounting hole 2111. Along the thickness direction X of the wall portion, a receiving groove 2112 is provided on the side of the wall portion 211 facing away from the electrode assembly 22. The mounting hole 2111 is provided on the groove bottom surface of the receiving groove 2112, and at least a part of the first insulating member 26 is received within the receiving groove 2112.

[0222] According to some embodiments of the present application, refer to Figures 3 to 4 and Figure 7As shown in the figure, the present application provides a battery cell 20, which includes a housing 21, an electrode assembly 22, and an electrode terminal 23. The housing 21 has a wall portion 211, and the wall portion 211 is provided with a mounting hole 2111 that penetrates the wall portion 211 along the thickness direction X of the wall portion. The housing 21 includes a housing body 212 and an end cap 213. An accommodation cavity with an opening 2121 is formed inside the housing body 212, and the end cap 213 closes the opening 2121. The end cap 213 is the wall portion 211. The electrode assembly 22 is accommodated in the accommodation cavity. The electrode terminal 23 includes a pole column 231 and a connecting member 232. The pole column 231 includes a body portion 2311 and an abutting portion 2312. The body portion 2311 penetrates through the mounting hole 2111 along the thickness direction X of the wall portion, and the abutting portion 2312 abuts against one side of the wall portion 211 facing the electrode assembly 22. The abutting portion 2312 is electrically connected to the tab 221 of the electrode assembly 22. The body portion 2311 and the abutting portion 2312 are integrally formed structures. Along the thickness direction X of the wall portion, the connecting member 232 is located on one side of the wall portion 211 facing away from the electrode assembly 22, and one end of the body portion 2311 away from the electrode assembly 22 is riveted to the connecting member 232. The connecting member 232 and the abutting portion 2312 cooperate to clamp the wall portion 211 to fasten the electrode terminal 23 to the wall portion 211. The connecting member 232 includes a first material layer 2321 and a second material layer 2322 that are stacked and compound-connected along the thickness direction X of the wall portion. The first material layer 2321 is located on the side of the second material layer 2322 facing away from the electrode assembly 22. The first material layer 2321 is electrically connected to the body portion 2311 of the pole column 231, and the first material layer 2321 is used for welding connection with the bus bar component. The material of the first material layer 2321 is the same as that of the bus bar component. The melting point of the second material layer 2322 is higher than that of the first material layer 2321. The melting point of the first material layer 2321 is MP1, and the melting point of the second material layer 2322 is MP2, satisfying MP2 - MP1 ≥ 200°C. Along the thickness direction X of the wall portion, the thickness of the first material layer 2321 is D1, and the thickness of the second material layer 2322 is D2, satisfying 0.1 ≤ D2 / D1 ≤ 0.25. The material of the first material layer 2321 includes aluminum, and the material of the second material layer 2322 includes steel. The second material layer 2322 is welded to the wall portion 211 to form a weld mark, and the weld mark surrounds the outside of the mounting hole 2111. The material of the second material layer 2322 is the same as that of the wall portion 211. Along the thickness direction X of the wall portion, a receiving groove 2112 is provided on one side of the wall portion 211 facing away from the electrode assembly 22. The mounting hole 2111 is provided on the bottom surface of the receiving groove 2112. At least a part of the connecting member 232 is received in the receiving groove 2112, and the second material layer 2322 is welded to the bottom surface of the receiving groove 2112.

[0223] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0224] The above are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A battery cell, characterized in that, include: The housing has a wall portion, the wall portion is provided with a mounting hole, and the mounting hole penetrates the wall portion along the thickness direction of the wall portion; an electrode assembly, contained in the housing; as well as The electrode terminal comprises a pole and a connector, wherein the pole is inserted into the mounting hole, the pole is electrically connected to the electrode assembly, and along the thickness direction of the wall portion, the connector is located on a side of the wall portion away from the electrode assembly, and the connector is connected to the pole; Among them, the connecting part includes a first material layer and a second material layer stacked along the thickness direction of the wall portion, the first material layer is located on the side of the second material layer away from the electrode assembly, the first material layer is electrically connected to the pole and is used to connect to the busbar component, and the melting point of the second material layer is higher than the melting point of the first material layer.

2. The battery cell according to claim 1, characterized in that, The melting point of the first material layer is MP1, and the melting point of the second material layer is MP2, satisfying MP2-MP1≥200°C.

3. The battery cell according to claim 1, wherein Along the thickness direction of the wall portion, the thickness of the first material layer is D1, and the thickness of the second material layer is D2, satisfying 0.1≤D2 / D1≤0.

25.

4. The battery cell according to claim 1, characterized in that, The first material layer and the second material layer are compositely connected.

5. The battery cell according to claim 1, characterized in that, The first material layer is made of aluminum, and the second material layer is made of steel.

6. The battery cell according to claim 1, wherein The pole comprises: A main body portion, which is inserted into the mounting hole along the thickness direction of the wall portion, and the main body portion is connected to the connecting member; The abutting portion abuts against a side of the wall portion facing the electrode assembly, and the abutting portion cooperates with the connecting member to clamp the wall portion so as to fasten the electrode terminal to the wall portion.

7. The battery cell according to claim 6, characterized in that, The main body is riveted to the first material layer.

8. The battery cell according to any one of claims 1-7, characterized in that, The electrode terminal is insulated and mounted on the wall portion.

9. The battery cell according to claim 8, wherein The battery cell further comprises: A first insulating member, along a thickness direction of the wall portion, at least a portion of the first insulating member is disposed between the connecting member and the wall portion, and the first insulating member is configured to insulate and isolate the connecting member from the wall portion; A second insulating member is provided along the thickness direction of the wall portion, at least a portion of the second insulating member is disposed between the pole and the wall portion, and the second insulating member is configured to insulate and isolate the pole and the wall portion.

10. The battery cell according to claim 9, wherein, The battery cell further comprises: A sealing member is disposed between the wall portion and the pole, and at least a portion of the sealing member is located in the mounting hole. The sealing member is configured to seal a gap between the pole and a hole wall surface of the mounting hole.

11. The battery cell according to claim 9, wherein Along the thickness direction of the wall portion, a receiving groove is provided on one side of the wall portion away from the electrode assembly, the mounting hole is provided on the bottom surface of the receiving groove, and at least a portion of the first insulating member is received in the receiving groove.

12. The battery cell according to claim 1, characterized in that, The second material layer is connected to the wall portion by welding.

13. The battery cell according to claim 12, characterized in that, The second material layer is connected to the wall portion by welding to form a welding mark, and the welding mark surrounds the outer side of the mounting hole.

14. The battery cell according to claim 12, wherein The material of the second material layer is the same as that of the wall portion.

15. The battery cell according to claim 12, wherein Along the thickness direction of the wall portion, a receiving groove is provided on the side of the wall portion facing away from the electrode assembly. The mounting hole is provided on the bottom surface of the receiving groove. At least a part of the connecting member is received in the receiving groove, and the second material layer is welded to the bottom surface of the receiving groove.

16. The battery cell according to claim 1, characterized in that, The housing includes: a housing body, which forms a receiving cavity with an opening inside, and the receiving cavity is used to receive the electrode assembly; an end cap for closing the opening; wherein, the end cap is the wall portion.

17. The battery cell according to claim 1, wherein The housing includes: a housing body, including an integrally formed side wall and the wall portion. The side wall surrounds the wall portion. Along the thickness direction of the wall portion, one end of the side wall is connected to the wall portion, and the other end encloses to form an opening. The side wall and the wall portion jointly define a receiving cavity for receiving the electrode assembly; an end cap for closing the opening.

18. A battery, characterized in that, It includes a battery cell according to any one of claims 1-17.

19. The battery according to claim 18, wherein The battery further includes: a current collecting member, which is welded to the first material layer to electrically connect the current collecting member and the pole post.

20. The battery according to claim 19, wherein, The material of the current collecting member is the same as the material of the first material layer.

21. An electrical device, characterized in that, It includes a battery cell according to any one of claims 1-17, and the battery cell is used to provide electrical energy.

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