Battery cell, battery, and electric device

Abstract

A battery cell (20), a battery (100), and an electric device, relating to the technical field of batteries. The battery cell (20) comprises a casing (21), an electrode assembly (22), and an electrode terminal (23). The casing (21) has a wall portion (211), and a mounting hole (2111) is formed in the wall portion (211). The electrode assembly (22) is accommodated in the casing (21). The electrode terminal (23) comprises a pole (231) and a connecting member (232). The pole (231) passes through the mounting hole (2111). The pole (231) is electrically connected to the electrode assembly (22). In the thickness direction of the wall portion (211), the connecting member (232) is located on the side of the wall portion (211) facing away from the electrode assembly (22), and the connecting member (232) is connected to the pole (231). The connecting member (232) comprises a first material layer (2321) and a second material layer (2322) which are stacked in the thickness direction of the wall portion (211). 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 pole (231) and is connected to a flow convergence component. The melting point of the second material layer (2322) is greater than that of the first material layer (2321). According to the battery cell (20) of such structure, the thickness of the first material layer (2321) can be optimized while weld penetration of the connecting member (232) is reduced, so as to reduce the space occupied by the connecting member (232) in the thickness direction of the wall portion (211).

Description

Battery cells, batteries and electrical devices Technical Field

[0001] 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

[0002] 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. As the core components of new energy vehicles, batteries have high requirements in terms of performance. The battery cell of a battery usually includes a shell and an electrode assembly housed in the shell, and the shell is provided with electrode terminals. 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 results in low space utilization of the battery cells after being assembled into groups, which is not conducive to improving the energy density of the battery.

[0003] Summary of the Invention

[0004] 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.

[0005] 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 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; 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.

[0006] In the above technical solution, the electrode terminal includes a pole and a connector, the pole is passed through 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 assembled with the convergence component, 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 with 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 of the battery cell after assembly, which is beneficial to improving the energy density of the battery with such a battery cell.

[0007] 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.

[0008] 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, and further reducing the risk of the connector being welded through.

[0009] 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.

[0010] 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 is sufficiently thick to separate and block the first material layer from the current collector during assembly by welding, thereby alleviating the risk 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, excessive waste of the second material layer thickness is reduced, thereby reducing the manufacturing cost of the connector and saving space occupied by the second material layer in the thickness direction of the wall, thereby improving the space utilization of the battery cells after assembly.

[0011] In some embodiments, the first material layer and the second material layer are compositely connected.

[0012] In the above technical solution, the first material layer and the second material layer are connected by a composite connection structure, which can effectively improve the structural strength and connection stability of the first material layer and the second material layer, and is conducive to reducing the risk of mutual separation between the first material layer and the second material layer.

[0013] In some embodiments, the material of the first material layer includes aluminum, and the material of the second material layer includes steel.

[0014] In the above technical solution, by setting the material of the first material layer to aluminum and the material of the second material layer to steel, on the one hand, the manufacturing cost of the connector can be reduced, and on the other hand, the melting point of the second material layer is made much higher than the melting point of the first material layer, so that the second material layer has a better separation and barrier effect when the first material layer is welded and assembled with the convergence component, thereby effectively reducing the risk of the connector being welded through.

[0015] In some embodiments, the pole includes a main body and a supporting portion; the main body is inserted into the mounting hole along the thickness direction of the wall, and the main body is connected to the connecting piece; the supporting portion is against the side of the wall facing the electrode assembly, and the supporting portion cooperates with the connecting piece to clamp the wall to fasten the electrode terminal to the wall.

[0016] In the above technical solution, the pole is provided with a main body portion which is passed through the mounting hole, and the two ends of the main body portion in the thickness direction of the wall portion are respectively connected with abutment portions and connecting pieces, so that the abutment portions and connecting pieces located on both sides of the wall portion in the thickness direction of the wall portion can cooperate and clamp the wall portion, thereby realizing the assembly of the electrode terminal on the wall portion, with a simple structure and easy assembly.

[0017] In some embodiments, the main body is riveted to the first material layer.

[0018] In the above technical solution, the main body of the pole is riveted to the first material layer of the connector to achieve an assembly connection between the pole and the connector. The structure is simple, easy to assemble, and has high structural stability, which is conducive to reducing the phenomenon of connection failure between the pole and the connector.

[0019] In some embodiments, the electrode terminal is insulated and mounted on the wall.

[0020] In the above technical solution, by insulating the electrode terminal and installing it on the wall, no electrical connection is formed between the electrode terminal and the wall. On the one hand, it is convenient for the electrode terminal to input or output the electrical energy of the battery cell, and on the other hand, it can reduce the risk of short circuit of the battery cell.

[0021] 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 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 and the wall portion; 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.

[0022] In the above technical solution, a first insulating member is provided between the connector and the wall portion so that the first insulating member can insulate and isolate the wall portion and the connector, thereby reducing the risk of short circuit between the wall portion and the connector. Correspondingly, a second insulating member is provided between the pole and the wall portion so that 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, the first insulating member and the second insulating member are respectively provided on both sides of the wall portion to achieve the insulated installation of the electrode terminal on the wall portion.

[0023] In some embodiments, the battery cell further includes a seal; the seal is disposed between the wall portion and the pole, and at least a portion of the seal is located within the mounting hole, and the seal is configured to seal the gap between the pole and the wall of the mounting hole.

[0024] In the above technical solution, a seal is provided between the wall and the pole of the electrode terminal, and at least a portion of the seal is located in the mounting hole, so that the seal can seal the gap between the pole and the wall of the mounting hole, thereby effectively reducing the phenomenon of electrolyte inside the battery cell overflowing from the mounting hole, thereby improving the stability and reliability of the battery cell.

[0025] In some embodiments, a receiving groove is provided on the side of the wall portion facing away from the electrode assembly along the thickness direction of the wall portion, 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.

[0026] In the above technical solution, by providing a receiving groove for accommodating the first insulating part on the side of the wall portion facing away from the electrode assembly, it is convenient to assemble the first insulating part between the connecting part and the wall portion, which can play a role in assembly positioning of the first insulating part, which is beneficial to reducing the difficulty of assembling the first insulating part, and can play a certain protective role for the first insulating part, so as to reduce the wear or damage of the first insulating part during use.

[0027] In some embodiments, the second material layer is connected to the wall portion by welding.

[0028] In the above technical solution, the second material layer of the connector is welded to the wall portion, so that the connector of the electrode terminal is electrically connected to the wall portion of the shell, thereby outputting or inputting the electrical energy of the battery cell. The battery cell adopting this structure does not need to set an insulating component for insulation isolation between the connector and the wall portion, which is conducive to reducing the manufacturing cost and assembly difficulty of the battery cell.

[0029] In some embodiments, the second material layer is welded to the wall portion to form a weld mark, and the weld mark surrounds the outer side of the mounting hole.

[0030] In the above technical solution, the weld mark formed by mutually welding the second material layer and the wall portion is arranged as a structure surrounding the outside of the mounting hole, so that the weld mark formed by mutually welding the second material layer and the wall portion is arranged around the mounting hole, so that the gap between the connector and the wall portion can be sealed by the weld mark, and there is no need to set a sealing component for sealing between the pole and the hole wall surface of the mounting hole, which is beneficial to reducing the manufacturing cost and assembly difficulty of the battery cell.

[0031] In some embodiments, the material of the second material layer is the same as the material of the wall portion.

[0032] In the above technical solution, by setting the material of the second material layer to be the same as the material of the wall portion, a structure in which the second material and the wall portion are welded with the same material can be achieved. On the one hand, the difficulty of welding between the second material layer and the wall portion can be reduced, and on the other hand, the occurrence of cold 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.

[0033] In some embodiments, a receiving groove is provided on the side of the wall portion facing away from the electrode assembly along the thickness direction of the wall portion, the mounting hole is provided on the bottom surface of the receiving groove, at least a portion of the connecting member is accommodated in the receiving groove, and the second material layer is welded to the bottom surface of the receiving groove.

[0034] In the above technical solution, by providing a receiving groove for accommodating the connecting piece on the side of the wall portion facing away from the electrode assembly, on the one hand, it can play a role in assembly positioning of the connecting piece, which is beneficial to reduce the welding difficulty between the wall portion and the second material layer of the connecting piece, and can improve the welding quality between the wall portion and the second material layer of the connecting piece. On the other hand, it can play a certain protective role for the connecting piece to reduce the phenomenon of wear or damage of the connecting piece during use.

[0035] In some embodiments, the housing includes a shell and an end cover; a receiving cavity with an opening is formed inside the shell, and the receiving cavity is used to receive the electrode assembly; the end cover closes the opening; wherein the end cover is the wall portion.

[0036] In the above technical solution, by setting the wall portion of the shell as the end cover for closing the opening of the shell, the battery cell adopting this structure is convenient for assembling the electrode terminal on the end cover, and is convenient for assembling and connecting the pole of the electrode terminal and the electrode assembly with each other, which is beneficial to reducing the difficulty of assembling the battery cell and improving the production efficiency of the battery cell.

[0037] In some embodiments, the outer shell includes a shell and an end cover; the shell includes an integrally formed side wall and the wall portion, the side wall is arranged around the wall portion, and along the thickness direction of the wall portion, one end of the side wall is connected to the wall portion, and the other end is enclosed to form an opening, and the side wall and the wall portion jointly define a accommodating cavity for accommodating the electrode assembly; the end cover closes the opening.

[0038] In the above technical solution, by setting the wall portion of the shell as a wall arranged opposite to the end cover in the thickness direction of the wall portion of the shell, the battery cell adopting this structure can make the area of ​​the shell where the electrode terminal is installed away from the end cover, and make there no direct connection relationship between the wall portion and the end cover, thereby alleviating the phenomenon that the force generated when the electrode terminal and other components pull or twist the wall portion acts on the end cover, thereby reducing the risk of connection failure between the end cover and the shell, and further helping to reduce the risk of leakage of the battery cell during use.

[0039] In a second aspect, an embodiment of the present application further provides a battery comprising the above-mentioned battery cell.

[0040] 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.

[0041] In the above technical solution, the electrical connection between the busbar component and the electrode terminal is achieved by welding the busbar component to the first material layer of the connector, thereby enabling the input or output of electrical energy from the battery cell through the busbar component. The connector is configured as a first material layer and a second material layer stacked along the thickness direction of the wall portion, with the second material layer 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. This allows the second material layer to act as a separator and barrier when the first material layer and the busbar component are welded together for assembly, thereby reducing the risk of the connector being welded through and affecting other components. This eliminates the need to increase the thickness of the first material layer to reduce the risk of the connector being welded through. Battery cells employing this structure can optimize the thickness of the first material layer while reducing the risk of the connector being welded through, thereby reducing the space occupied by the connector in the thickness direction of the wall portion. This effectively improves the space utilization of the battery cells after assembly, thereby facilitating an increase in the energy density of a battery having such battery cells.

[0042] In some embodiments, the material of the conduit component is the same as that of the first material layer.

[0043] In the above technical solution, by setting the material of the convergence component to be the same as the material of the first material layer, it is possible to achieve a structure in which the convergence component and the first material layer are welded with the same material. On the one hand, it can reduce the difficulty of welding between the convergence component and the first material layer. On the other hand, it can reduce the occurrence of cold welding or welding failure between the convergence component and the first material layer, which is beneficial to improving the welding quality between the convergence component and the first material layer.

[0044] In a third aspect, an embodiment of the present application further provides an electrical device, comprising the above-mentioned battery cell, wherein the battery cell is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0046] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0047] FIG2 is an exploded view of the structure of a battery provided in some embodiments of the present application;

[0048] FIG3 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0049] FIG4 is an exploded view of the structure of a battery cell provided in some embodiments of the present application;

[0050] FIG5 is a partial cross-sectional view of a battery cell provided in some embodiments of the present application;

[0051] FIG6 is a cross-sectional view of an electrode terminal of a battery cell provided in some embodiments of the present application;

[0052] FIG7 is a partial cross-sectional view of a battery cell provided in some other embodiments of the present application.

[0053] Icon: 1000-vehicle; 100-battery; 10-box; 11-first box body; 12-second box body; 20-battery cell; 21-housing; 211-wall; 2111-mounting hole; 2112-accommodating groove; 212-shell; 2121-opening; 213-end cover; 22-electrode assembly; 221-ear; 23-electrode terminal; 231-pole; 2311-main body; 2312-resting part; 232-connector; 2321-first material layer; 2321a-rivet 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. DETAILED DESCRIPTION

[0054] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0055] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0056] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0057] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0058] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0059] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0060] The term "plurality" used in this application refers to two or more (including two).

[0061] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0062] The battery cells can be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, etc., which are not limited in the embodiments of the present application.

[0063] A battery cell typically includes an electrode assembly. This assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of a battery cell, active ions (such as lithium ions) are inserted and removed between the positive and negative electrodes. The separator, placed between the positive and negative electrodes, prevents short circuits between the positive and negative electrodes while allowing the active ions to pass through.

[0064] 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.

[0065] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is provided on either or both of the two facing surfaces of the positive electrode current collector.

[0066] 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 a silver-plated surface, stainless steel with a silver-plated 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 (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0067] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides and their respective modified compounds. However, the present application is not limited to these materials, and other traditional 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 phosphates may include but are not limited to at least one of lithium iron phosphate (such as LiFePO4 (also referred to 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 iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. 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 LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM622 ), LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2) and at least one of its modified compounds, etc.

[0068] In some embodiments, a positive electrode may utilize a metal foam. The metal foam may include nickel foam, copper foam, aluminum foam, alloy foam, or the like. When a metal foam is used as the positive electrode, the surface of the metal foam may or may not include a positive electrode active material. For example, a lithium source material, potassium metal, or sodium metal may be filled or / and deposited within the metal foam, where the lithium source material is lithium metal and / or a lithium-rich material.

[0069] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0070] As an example, the negative electrode current collector may be a metal foil, a metal foam, or a composite current collector. For example, as the metal foil, aluminum or stainless steel treated with silver, stainless steel, copper, aluminum, nickel, carbon electrode, nickel, or titanium, etc. may be used. The metal foam may be nickel foam, copper foam, aluminum foam, alloy foam, 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 (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0071] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0072] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is provided on either or both of the two facing surfaces of the negative electrode current collector.

[0073] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells that is well known in the art. 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, lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0074] 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.

[0075] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0076] In some embodiments, the separator is a separator membrane. There are many types of separator membranes, and any known separator membrane with a porous structure having good chemical stability and mechanical stability can be selected.

[0077] As an example, the separator can be made of at least one of fiberglass, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator can be a single-layer film or a multi-layer composite film. In the case of a multi-layer composite film, the materials of each layer can be the same or different. The separator can be a separate component positioned between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes.

[0078] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transport ions and isolate the positive and negative electrodes.

[0079] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel, or solid. Liquid electrolytes include an electrolyte salt and a solvent.

[0080] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonyl imide, lithium bistrifluoromethanesulfonyl imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalatoborate, lithium bisoxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0081] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl 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, cyclopentane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent may also be an ether solvent. The ether solvent may 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.

[0082] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0083] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0084] As an example, the polymer solid electrolyte may be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, a single ion polymer, polyionic liquid-lithium salt, cellulose, or the like.

[0085] As an example, the inorganic solid electrolyte may include an oxide solid electrolyte (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superion conductor (lithium germanium phosphosulfide, silver germanium sulfide), amorphous sulfide) and one or more of a halide solid electrolyte, a nitride solid electrolyte and a hydride solid electrolyte.

[0086] As an example, a composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0087] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into the wound structure.

[0088] In some embodiments, the electrode assembly is a laminate structure.

[0089] As an example, multiple positive electrode sheets and multiple negative electrode sheets can be provided respectively, and the multiple positive electrode sheets and the multiple negative electrode sheets can be alternately stacked.

[0090] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet may be folded to form a plurality of stacked folded segments, with a positive electrode sheet being sandwiched between adjacent folded segments.

[0091] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of folded segments that are stacked.

[0092] As an example, a plurality of separators may be provided, each of which is disposed between any adjacent positive electrode sheets or negative electrode sheets.

[0093] As an example, the separator may be provided continuously, and may be provided between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0094] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0095] In some embodiments, the electrode assembly is provided with tabs that can conduct current from the electrode assembly. The tabs include a positive tab and a negative tab.

[0096] In some embodiments, a battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (e.g., polypropylene), a composite metal housing (e.g., a copper-aluminum composite housing), or an aluminum-plastic film.

[0097] As an example, the battery cells may be cylindrical, prismatic, soft-pack or other shaped battery cells. Prismatic battery cells include but are not limited to square-shell, blade-shaped, and polygonal batteries, such as hexagonal batteries.

[0098] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity.

[0099] In some embodiments, the battery may be a battery module. When there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0100] In some embodiments, the battery may be a battery pack, which includes a case and battery cells, wherein the battery cells or battery modules are housed in the case.

[0101] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0102] In some embodiments, the battery may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0103] Batteries, with their outstanding advantages such as high energy density, low environmental pollution, high power density, long service life, wide adaptability, and low self-discharge coefficient, are a vital component of today's new energy development. The development of battery technology requires simultaneous consideration of multiple design factors, including performance parameters such as energy density, cycle life, discharge capacity, and charge / discharge rate. Furthermore, the quality of the battery during the production process must also be considered.

[0104] For a typical battery cell, the battery cell generally includes a housing and an electrode assembly housed within the housing, with electrode terminals mounted on the housing. By connecting the electrode terminals to the electrode assembly and the battery's current collector, the battery cell's electrical energy can be input or output. To reduce the difficulty of assembling the electrode terminal and improve its assembly stability, in related art, the electrode terminal is provided with a pole and a rivet block. The pole is inserted into a mounting hole in the housing and is interconnected with the electrode assembly. The rivet block is located outside the housing, and the pole is riveted to the rivet block to enable the electrode terminal to be assembled on the housing. By welding the rivet block to the battery's current collector, the battery cell's electrical energy can be input or output. However, in battery cells of this structure, in order to reduce the risk of welding through when the rivet block and the busbar 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 shell. After the battery cells are assembled into groups, the area on the outside of the battery cells where the rivet block is protruding 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.

[0105] Based on the above considerations, in order to solve the problem of low space utilization of battery cells after assembly 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 passes through 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 passed through 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 busbar component, and the melting point of the second material layer is higher than the melting point of the first material layer.

[0106] 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 assembled with the convergence component, 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 with 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 of the battery cell after assembly, which is beneficial to improving the energy density of the battery with such a battery cell.

[0107] The battery cells disclosed in the embodiments of this application can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. A power supply system comprising the battery cells and batteries disclosed in this application can be used to construct such electrical devices. This helps alleviate the problem of low space utilization of battery cells after assembly, thereby increasing the battery's energy density.

[0108] The present invention provides an electric device that uses a battery as a power source. The electric device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, etc. 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. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0109] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device according to an embodiment of the present application.

[0110] Please refer to Figure 1, which is a structural schematic diagram of a vehicle 1000 provided in some embodiments of the present application. The 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 or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000. The battery 100 can be arranged at the bottom of the vehicle 1000, or at the head of the vehicle 1000, or at the tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can be used as an operating power source or a power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0111] In some embodiments of the present application, the battery 100 can not only serve as the operating power source or usage power source of the vehicle 1000, but also serve as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0112] 2 and 3 , FIG2 is an exploded view of a battery 100 according to some embodiments of the present invention, and FIG3 is a schematic diagram of a battery cell 20 according to some embodiments of the present invention. The battery 100 includes a housing 10 and a battery cell 20 , wherein the battery cell 20 is accommodated in the housing 10 .

[0113] The housing 10 is used to provide assembly space for the battery cells 20 and can adopt a variety of structures. In some embodiments, the housing 10 can include a first housing body 11 and a second housing body 12. The first housing body 11 and the second housing body 12 cover each other, and the first housing body 11 and the second housing body 12 jointly define an assembly space for accommodating the battery cells 20. The second housing body 12 can be a hollow structure with one end open, and the first housing body 11 can be a plate-like structure. The first housing body 11 covers the open side of the second housing body 12, so that the first housing body 11 and the second housing body 12 jointly define the assembly space. The first housing body 11 and the second housing body 12 can also be hollow structures with one end open, and the open side of the first housing body 11 covers the open side of the second housing body 12.

[0114] Of course, the box body 10 formed by the first box body 11 and the second box body 12 can be in various shapes, such as a cylinder, a cuboid or a cube, etc. For example, in FIG2 , the box body 10 is in the shape of a cuboid.

[0115] In the battery 100, there can be one or more battery cells 20 disposed within the housing 10. When there are multiple battery cells 20 disposed within the housing 10, the multiple battery cells 20 can be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to a combination of series and parallel configurations within the multiple battery cells 20. The multiple battery cells 20 can be directly connected in series, in parallel, or in a hybrid configuration, and then the entire structure formed by the multiple battery cells 20 is housed within the housing 10. Alternatively, the battery 100 can be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid configuration to form a battery module, which is then further connected in series, in parallel, or in a hybrid configuration to form a single structure, which is then housed within the housing 10.

[0116] In some embodiments, the battery 100 may further include other structures. For example, the battery 100 may further include a busbar component, which is used to connect the multiple battery cells 20 to achieve electrical connection between the multiple battery cells 20. The busbar component plays the role of connecting the multiple battery cells 20 in series, in parallel, or in hybrid connection. The material of the busbar component can be copper, iron, aluminum, or an aluminum alloy.

[0117] 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 a rectangular parallelepiped, a cylinder, a prism, or other shapes. For example, in FIG3 , the battery cell 20 is a rectangular parallelepiped.

[0118] According to some embodiments of the present application, referring to FIG3 and further referring to FIG4, FIG5 and FIG6, FIG4 is an exploded view of the structure of a battery cell 20 provided in some embodiments of the present application, FIG5 is a partial cross-sectional view of a battery cell 20 provided in some embodiments of the present application, and FIG6 is a 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 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. The mounting hole 2111 passes through the wall portion 211 along the thickness direction X of the wall portion. The electrode assembly 22 is accommodated in the housing 21. The electrode terminal 23 includes a post 231 and a connector 232. The post 231 is inserted into the mounting hole 2111 and is electrically connected to the electrode assembly 22. Along the wall thickness direction X, the connector 232 is located on the side of the wall 211 facing away from the electrode assembly 22 and is connected to the post 231. The connector 232 includes a first material layer 2321 and a second material layer 2322 stacked along the wall thickness direction X. 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 post 231 and is used to connect to the busbar. The second material layer 2322 has a higher melting point than the first material layer 2321.

[0119] The housing 21 can also be used to accommodate an electrolyte, such as an electrolyte solution. The housing 21 can have various structural forms. The housing 21 can also be made of various materials, such as copper, iron, aluminum, steel, and aluminum alloys.

[0120] In some embodiments, the housing 21 may include a shell 212 and an end cover 213, wherein a accommodating cavity is formed inside the shell 212, and the accommodating cavity has an opening 2121, that is, the shell 212 is a hollow structure with one end open, and the end cover 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.

[0121] Optionally, the wall portion 211 for mounting the electrode terminal 23 and provided with the mounting hole 2111 may be the end cap 213, or may be one of the multiple walls of the housing 212. For example, in Figures 3 and 4, the wall portion 211 is the end cap 213 of the housing 21. Of course, in other embodiments, the wall portion 211 may also be the bottom wall of the housing 212 disposed opposite the end cap 213 in the thickness direction X of the wall portion, or a side wall adjacent to and abutting the end cap 213.

[0122] When assembling the battery cell 20 , the electrode assembly 22 may be placed in the housing 212 , 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 .

[0123] The mounting hole 2111 penetrates the wall portion 211 along the thickness direction X of the wall portion. That is, the mounting hole 2111 extends along the thickness direction X of the wall portion and penetrates the surfaces of both sides of the wall portion 211 .

[0124] The housing 212 can have a variety of shapes, such as a cylinder, a rectangular parallelepiped, etc. The shape of the housing 212 can be determined based on the specific shape of the electrode assembly 22. For example, if the electrode assembly 22 has a cylindrical structure, the housing 212 can have a cylindrical structure; if the electrode assembly 22 has a rectangular parallelepiped structure, the housing 212 can have a rectangular parallelepiped structure. Of course, the end cap 213 can also have a variety of structures, such as a plate-like structure or a hollow structure with one end open. For example, in Figure 4, the housing 212 has a rectangular parallelepiped structure and the end cap 213 has a plate-like structure.

[0125] It is understandable 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 shell body 212 and two end covers 213. The shell body 212 is a hollow structure with openings 2121 on opposite sides. One end cover 213 corresponds to an opening 2121 of the shell body 212 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 22 and the electrolyte.

[0126] The electrode assembly 22 is a component in the battery cell 20 where electrochemical reactions occur. The structure of the electrode assembly 22 can be various. For example, the electrode assembly 22 can be a wound structure formed by winding the positive electrode sheet, the separator and the negative electrode sheet, or it can be a stacked structure formed by stacking the positive electrode sheet, the separator and the negative electrode sheet.

[0127] Illustratively, the separator is an isolation membrane, and a main material of the isolation membrane may be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride.

[0128] The electrode assembly 22 has a tab 221 formed at one end near the wall 211 in the thickness direction X of the wall. 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 formed by the stacked connection of the regions of the positive electrode sheet not coated with the positive electrode active material layer, or the stacked connection of the regions of the negative electrode sheet not coated with the negative electrode active material layer. If the tab 221 is used to output the positive electrode of the electrode assembly 22, the tab 221 is formed by the stacked connection of the regions of the positive electrode sheet not coated with the positive electrode active material layer; if the tab 221 is used to output the negative electrode of the electrode assembly 22, the tab 221 is formed by the stacked connection of the regions of the negative electrode sheet not coated with the negative electrode active material layer.

[0129] For example, the material of the tab 221 may be copper or aluminum.

[0130] Optionally, the number of electrode assemblies 22 housed in the housing 21 may be one or more. For example, in FIG4 , the housing 21 of the battery cell 20 is provided with two electrode assemblies 22 , which are stacked along the thickness direction thereof. In other words, the two electrode assemblies 22 are stacked along the thickness direction of the battery cell 20. Of course, in other embodiments, the number of electrode assemblies 22 housed in the housing 21 may be one, three, four, five, six, seven, or eight, etc.

[0131] The electrode terminal 23 serves to output or input the electrical 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 electrical energy of the battery cell 20 .

[0132] The electrode terminal 23 includes a pole 231 and a connector 232. The pole 231 and the connector 232 are connected to each other. The pole 231 is used to electrically connect to the electrode assembly 22, and the connector 232 is used to electrically connect to the busbar component to achieve electrical connection between the electrode assembly 22 and the busbar component, so as to output or input electrical energy of the battery cell 20.

[0133] 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 connector 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.

[0134] In FIG5 , a portion of the pole 231 abuts against the side of the wall 211 facing the electrode assembly 22, that is, the pole 231 has a portion located on the side of the wall 211 facing the electrode assembly 22, and this portion overlaps with the wall 211 in the wall thickness direction X, so that the pole 231 can abut against the side of the wall 211 facing the electrode assembly 22 along the wall thickness direction X, so that the pole 231 can cooperate with the connector 232 located on the side of the wall 211 facing 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 directly abut against the side of the wall 211 facing the electrode assembly 22, or it can indirectly abut against the side of the wall 211 facing the electrode assembly 22 through other components.

[0135] The pole 231 serves to connect the electrode assembly 22 to achieve electrical connection between the electrode assembly 22 and the electrode terminal 23. Optionally, the pole 231 can be directly connected to the pole ear 221 of the electrode assembly 22, or indirectly connected to the pole ear 221 of the electrode assembly 22 through other components.

[0136] In some embodiments, as shown in Figure 4, the battery cell 20 may further include a current collecting member 24, which is disposed in the outer shell 21. The current collecting member 24 connects the pole 231 of the electrode terminal 23 and the pole ear 221 of the electrode assembly 22 to achieve electrical connection between the electrode assembly 22 and the electrode terminal 23.

[0137] Illustratively, the current collecting member 24 is welded to the pole 231 and to the tab 221. Of course, in other embodiments, the current collecting member 24 may also be in contact with or bonded to the pole 231, and similarly, the current collecting member 24 may also be in contact with or bonded to the tab 221.

[0138] The current collecting member 24 connects the pole 231 of the electrode terminal 23 and the tab 221 of the electrode assembly 22 . The current collecting member 24 can be made of various materials, for example, copper, iron, aluminum, steel, aluminum alloy, etc.

[0139] In Figure 4, the battery cell 20 includes two electrode terminals 23 and two current collecting members 24. Correspondingly, each electrode assembly 22 has two pole tabs 221, and the polarities of the two pole tabs 221 are opposite. The two electrode terminals 23 are electrically connected to the two pole tabs 221 of the electrode assembly 22 through the two current collecting members 24 to realize the input or output of the positive and negative electrodes of the battery cell 20.

[0140] Optionally, both electrode terminals 23 are mounted on the wall portion 211, and each electrode terminal 23 is electrically connected to a 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 may also be mounted on different walls of the housing 21. For example, in some embodiments, the two electrode terminals 23 may also be respectively disposed on two walls of the housing 21 that are opposite to each other in the thickness direction X of the wall portion.

[0141] The connecting piece 232 is located on the side of the wall 211 away from the electrode assembly 22, and the connecting piece 232 is connected to the pole 231. That is, the connecting piece 232 is located on the outside of the shell 21, and the connecting piece 232 is connected to the part of the pole 231 extending out of the mounting hole 2111 away from the electrode assembly 22, so that the connecting piece 232 and the pole 231 can cooperate to clamp the wall 211, thereby realizing the assembly of the electrode terminal 23 to the wall 211.

[0142] Exemplarily, one end of the pole 231 away from the electrode assembly 22 in the thickness direction X of the wall is riveted to the connector 232 to connect the pole 231 to the connector 232. Of course, in other embodiments, the pole 231 and the connector 232 can also be connected to each other through structures such as welding, clamping or bolting.

[0143] The connector 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, bolting, composite connection, or welding. For example, in the embodiment of the present application, the first material layer 2321 and the second material layer 2322 are compositely connected, such as by hot pressing or cold pressing.

[0144] The first material layer 2321 is located on a side of the second material layer 2322 away from the electrode assembly 22 . That is, 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.

[0145] The first material layer 2321 is used for welding connection with the busbar component. In other words, the first material layer 2321 plays the role of welding connection with the busbar component of the battery 100, so that the battery cell 20 can be electrically connected to the busbar component, thereby enabling the busbar component to be electrically connected to the terminal 231 through the first material layer 2321. Exemplarily, the first material layer 2321 is welded to the busbar component on the side of the wall portion facing away from the electrode assembly 22 in the thickness direction X.

[0146] In some embodiments, as shown in Figures 3 and 4, the battery cell 20 may further include a pressure relief mechanism 25, which is provided on the housing 21 and is used to release the pressure inside the battery cell 20 when the internal pressure or temperature of the battery cell 20 reaches a predetermined value.

[0147] Optionally, the pressure relief mechanism 25 may be provided on the end cover 213 of the housing 21 or on the shell 212 of the housing 21. For example, in FIG3 and FIG4 , the pressure relief mechanism 25 is provided on the end cover 213.

[0148] Similarly, the pressure relief mechanism 25 and the housing 21 can be integrally formed or separately formed. For example, in FIG4 , the pressure relief mechanism 25 and the housing 21 are separate structures, and the pressure relief mechanism 25 can be connected to the housing 21 by welding or other methods. Accordingly, the pressure relief mechanism 25 can be a pressure relief component such as an explosion-proof valve, explosion-proof disk, air valve, pressure relief valve, or safety valve. Of course, in other embodiments, the pressure relief mechanism 25 and the housing 21 can also be integrally formed, in which case the pressure relief mechanism 25 is a region of the housing 21 where a weak structure is formed, such as a region of the housing 21 where a notched groove is provided.

[0149] 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 as to realize the assembly of the electrode terminal 23 on the wall portion 211, by setting the connecting member 232 as a first material layer 2321 and a 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 electrode terminal 23 is assembled on the wall portion 211. The second material layer 2322 can play a certain role in separation and barrier when the first material layer 2321 is welded and assembled with the convergence component, 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.

[0150] 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.

[0151] 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.

[0152] Exemplarily, the material of the first material layer 2321 and the material of the busbar component are aluminum or aluminum alloy, etc. Correspondingly, the material of the second material layer 2322 can be steel, copper, iron or silver, etc.

[0153] In this embodiment, by setting the melting point of the second material layer 2322 to be greater than or equal to 200 degrees Celsius than the melting point of the first material layer 2321, the phenomenon of the second material layer 2322 being melted when the first material layer 2321 is welded and assembled with the convergence component can be further alleviated, thereby further improving the separation effect and barrier effect of the second material layer 2322, and further reducing the risk of the connector 232 being welded through.

[0154] According to some embodiments of the present application, as shown in FIG6 , 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.

[0155] For example, 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.

[0156] 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 the first material layer 2321 from the current collector during assembly by welding, thereby mitigating the risk of weld penetration of the second material layer 2322. 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, excessive waste of the thickness of the second material layer 2322 is reduced, thereby reducing the manufacturing cost of the connector 232 and conserving the space occupied by the second material layer 2322 in the thickness direction X of the wall, thereby improving the space utilization of the assembled battery cells 20.

[0157] In some embodiments, the first material layer 2321 and the second material layer 2322 are compositely connected.

[0158] The first material layer 2321 and the second material layer 2322 may be connected to each other in various ways. For example, the first material layer 2321 and the second material layer 2322 may be connected by a composite process such as hot pressing or cold pressing. Of course, in other embodiments, the first material layer 2321 and the second material layer 2322 may also be connected by bonding, clamping, or welding.

[0159] In this embodiment, a composite connection structure is used 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 conducive to reducing the risk of separation between the first material layer 2321 and the second material layer 2322.

[0160] In some embodiments, the first material layer 2321 is made of aluminum, and the second material layer 2322 is made of steel. It should be noted that when the first material layer 2321 is made of aluminum, the second material layer 2322 can also be made of copper, iron, or silver.

[0161] In this embodiment, by setting the material of the first material layer 2321 to aluminum and the material of the second material layer 2322 to 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 the melting point of the first material layer 2321, so that the second material layer 2322 has a better separation and barrier effect when the first material layer 2321 is welded and assembled with the conduit component, thereby effectively reducing the risk of the connector 232 being welded through.

[0162] According to some embodiments of the present application, as shown in Figures 5 and 6, the electrode post 231 may include a body portion 2311 and an abutting portion 2312. The body portion 2311 is disposed within 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. The abutting portion 2312 cooperates with the connector 232 to clamp the wall portion 211 to secure the electrode terminal 23 to the wall portion 211.

[0163] Among them, the main body 2311 of the pole 231 is a structure inserted into the mounting hole 2111 along the thickness direction X of the wall, and the two ends of the main body 2311 in the thickness direction X of the wall extend out of the two ends of the mounting hole 2111 respectively, so that the two ends of the main body 2311 can be connected to the connecting piece 232 and the abutting portion 2312 respectively.

[0164] Optionally, the connection structure between the connector 232 and the main body 2311 can be various, such as welding, riveting, clamping or bolt connection.

[0165] The abutting portion 2312 abuts against the side of the wall portion 211 facing the electrode assembly 22, and the abutting portion 2312 cooperates with the connecting piece 232 to clamp the wall portion 211. That is, 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 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 piece 232 to clamp the wall portion 211.

[0166] It should be noted that the abutting portion 2312 can be directly abutted against the side of the wall portion 211 facing the electrode assembly 22, or can be indirectly abutted against the side of the wall portion 211 facing the electrode assembly 22 through other components. For example, in FIG5 , the electrode terminal 23 is a structure that is insulated and mounted on the wall portion 211, and a second insulating member 27 is provided between the abutting portion 2312 of the pole 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. Referring to FIG7 , FIG7 is a partial cross-sectional view of a battery cell 20 provided in some other embodiments of the present application, in which the electrode terminal 23 is a structure that is electrically connected to the wall portion 211 of the housing 21, so that the abutting portion 2312 of the pole 231 directly abuts against the side of the wall portion 211 facing the electrode assembly 22.

[0167] For example, in FIG6 , the main body 2311 and the abutting portion 2312 are an integrally formed structure, that is, the main body 2311 and the abutting portion 2312 are an integrally formed structure, and the main body 2311 and the abutting portion 2312 can be made by an integral forming process such as casting, stamping, or milling. Of course, in other embodiments, the main body 2311 and the abutting portion 2312 can also be a separate structure, that is, the main body 2311 and the abutting portion 2312 can also be a separate structure, and the abutting portion 2312 can be connected to the end of the main body 2311 facing the electrode assembly 22 in the thickness direction X of the wall portion by welding, clamping, or bolting.

[0168] In this embodiment, the pole 231 is provided with a main body portion 2311 which is passed through the mounting hole 2111, and the two ends of the main body portion 2311 in the thickness direction X of the wall portion are respectively connected with a supporting portion 2312 and a connecting member 232, so that the supporting 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 and clamp the wall portion 211, thereby realizing the assembly of the electrode terminal 23 on the wall portion 211, which has a simple structure and is easy to assemble.

[0169] In some embodiments, as shown in FIG. 6 , the main body 2311 is riveted to the first material layer 2321 .

[0170] Among them, the second material layer 2322 is provided with a channel for the main body 2311 to pass through along the thickness direction X of the wall, and the first material layer 2321 is provided with a rivet hole 2321a, the rivet hole 2321a passes through both sides of the first material layer 2321 along the thickness direction X of the wall, and the rivet hole 2321a is connected with the channel of the second material layer 2322, and the end of the main body 2311 away from the electrode assembly 22 in the thickness direction X of the wall is inserted into the rivet hole 2321a and riveted to the first material layer 2321.

[0171] In this embodiment, the main body 2311 of the pole 231 is riveted to the first material layer 2321 of the connector 232 to achieve an assembly connection between the pole 231 and the connector 232. This has a simple structure, is easy to assemble, and has high structural stability, which helps to reduce the phenomenon of connection failure between the pole 231 and the connector 232.

[0172] According to some embodiments of the present application, as shown in FIG5 , the electrode terminal 23 is insulated and mounted on the wall portion 211 . In other words, no electrical connection is formed between the electrode terminal 23 and the housing 21 .

[0173] In this embodiment, the electrode terminal 23 is insulated and installed on the wall portion 211, so that 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 electrical energy of the battery cell 20, and on the other hand, it can reduce the risk of short circuit of the battery cell 20.

[0174] In some embodiments, referring again to FIG. 5 , 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 portion of the first insulating member 26 is disposed between the connector 232 and the wall portion 211 , and the first insulating member 26 is configured to insulate and isolate the connector 232 from the wall portion 211 . Along the thickness direction X of the wall portion, at least a portion of the second insulating member 27 is disposed between the terminal 231 and the wall portion 211 , and the second insulating member 27 is configured to insulate and isolate the terminal 231 from the wall portion 211 .

[0175] Optionally, the first insulating member 26 serves to insulate and isolate the connector 232 from the wall 211 . The first insulating member 26 can be made of a variety of materials, such as rubber, silicone, or plastic. Similarly, the second insulating member 27 serves to insulate and isolate the pole 231 from the wall 211 . The second insulating member 27 can also be made of a variety of materials, such as rubber, silicone, or plastic.

[0176] In this embodiment, a first insulating member 26 is provided between the connector 232 and the wall portion 211 so that the first insulating member 26 can insulate and isolate the wall portion 211 and the connector 232, thereby reducing the risk of short circuit between the wall portion 211 and the connector 232. Correspondingly, a second insulating member 27 is provided between the pole 231 and the wall portion 211 so that the second insulating member 27 can insulate and isolate the wall portion 211 and the pole 231, thereby reducing the risk of short circuit between the wall portion 211 and the pole 231. Furthermore, a first insulating member 26 and a second insulating member 27 are respectively provided on both sides of the wall portion 211 to achieve an insulated installation of the electrode terminal 23 on the wall portion 211.

[0177] In some embodiments, as shown in FIG5 , the battery cell 20 may further include a seal 28 . The seal 28 is disposed between the wall portion 211 and the terminal post 231 , with at least a portion of the seal 28 located within the mounting hole 2111 . The seal 28 is configured to seal the gap between the terminal post 231 and the wall of the mounting hole 2111 .

[0178] In which, in an embodiment where the pole 231 includes a main body portion 2311 and an abutting portion 2312, the seal 28 is sleeved on the outside of the main body portion 2311, and the seal 28 is located between the main body portion 2311 and the wall surface of the mounting hole 2111, so that the seal 28 can seal the gap between the main body portion 2311 and the wall surface of the mounting hole 2111.

[0179] At least part of the seal 28 is located in the mounting hole 2111, that is, the seal 28 can be completely located in the mounting hole 2111, or only partially located in the mounting hole 2111. In Figure 5, part of the seal 28 is located in the mounting hole 2111, and the other part is located between the wall portion 211 and the abutment portion 2312 of the pole 231.

[0180] For example, the sealing member 28 may be made of rubber, silicone, plastic, or the like.

[0181] In this embodiment, a sealant 28 is provided between the wall portion 211 and the pole 231 of the electrode terminal 23, and at least a portion of the sealant 28 is located within the mounting hole 2111, so that the sealant 28 can seal the gap between the pole 231 and the wall surface of the mounting hole 2111, thereby effectively reducing the phenomenon of electrolyte inside the battery cell 20 overflowing from the mounting hole 2111, thereby improving the stability and reliability of the battery cell 20.

[0182] In some embodiments, please continue to refer to Figure 5. Along the thickness direction X of the wall, a receiving groove 2112 is provided on the side of the wall 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 portion of the first insulating member 26 is accommodated in the receiving groove 2112.

[0183] The mounting hole 2111 is provided on the bottom surface of the receiving groove 2112 , that is, the mounting hole 2111 is a structure penetrating the bottom surface of the receiving groove 2112 along the thickness direction X of the wall.

[0184] Illustratively, a portion of the first insulating member 26 is accommodated in the accommodation groove 2112 . Of course, in other embodiments, the first insulating member 26 may also be entirely located in the accommodation groove 2112 .

[0185] In this embodiment, by providing an accommodating groove 2112 for accommodating 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 assembly positioning of the first insulating member 26, which is beneficial to reducing the difficulty of assembling the first insulating member 26, and can play a certain protective role for the first insulating member 26, so as to reduce the wear or damage of the first insulating member 26 during use.

[0186] According to some embodiments of the present application, as shown in FIG. 7 , the second material layer 2322 is welded to the wall portion 211 .

[0187] The second material layer 2322 and the wall portion 211 are welded to each other, so that the second material layer 2322 of the connector 232 is electrically connected to the wall portion 211 , thereby electrically connecting the electrode terminal 23 to the housing 21 .

[0188] 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 outer shell 21, and the other electrode terminal 23 is a structure insulated and installed from the outer shell 21 (as shown in Figure 5). Of course, the battery cell 20 can also be a structure in which both electrode terminals 23 are insulated and installed from the outer shell 21.

[0189] In this embodiment, the second material layer 2322 of the connector 232 is welded to the wall portion 211, so that the connector 232 of the electrode terminal 23 is electrically connected to the wall portion 211 of the outer shell 21, thereby outputting or inputting electrical energy of the battery cell 20. The battery cell 20 adopting this structure does not need to set an insulating component for insulation isolation between the connector 232 and the wall portion 211, which is beneficial to reducing the manufacturing cost and assembly difficulty of the battery cell 20.

[0190] In some embodiments, referring to FIG. 7 , the second material layer 2322 is welded to the wall portion 211 to form a weld mark (not shown), which surrounds the outside of the mounting hole 2111. In other words, the weld mark formed by the welding of the second material layer 2322 and the wall portion 211 is an annular structure disposed around the mounting hole 2111 and located between the second material layer 2322 and the wall portion 211.

[0191] In this embodiment, the weld mark formed by welding the second material layer 2322 and the wall portion 211 to each other is set as a structure surrounding the outside of the mounting hole 2111, so that the weld mark formed by welding the second material layer 2322 and the wall portion 211 to each other is set around the mounting hole 2111, so that the gap between the connector 232 and the wall portion 211 can be sealed by the weld mark, and there is no need to set a sealing component for sealing between the pole 231 and the wall surface of the mounting hole 2111, which is beneficial to reducing the manufacturing cost and assembly difficulty of the battery cell 20.

[0192] In some embodiments, the material of the second material layer 2322 is the same as that of the wall portion 211 .

[0193] It should be noted that the material of the second material layer 2322 is the same as the material of the wall portion 211, which means that the main component of the second material layer 2322 is the same as the main component of the wall portion 211. For example, if the second material layer 2322 and the wall portion 211 are both made of a single material, then 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, then the material of the second material layer 2322 and the wall portion 211 is the same as the main component of the second material layer 2322 and the wall portion 211. If the second material layer 2322 and the wall portion 211 only differ in the content of the components, then they are also the same material.

[0194] 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, it is possible to achieve a structure in which the second material and the wall portion 211 are welded with the same material. On the one hand, it can reduce the difficulty of welding between the second material layer 2322 and the wall portion 211. On the other hand, it can reduce the occurrence of cold welding or welding failure between the second material layer 2322 and the wall portion 211, which is beneficial to improving the welding quality between the second material layer 2322 and the wall portion 211.

[0195] In some embodiments, as shown in Figure 7, 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 portion of the connecting member 232 is accommodated in the receiving groove 2112, and the second material layer 2322 is welded to the bottom surface of the receiving groove 2112.

[0196] The mounting hole 2111 is provided on the bottom surface of the receiving groove 2112 , that is, the mounting hole 2111 is a structure penetrating the bottom surface of the receiving groove 2112 along the thickness direction X of the wall.

[0197] Exemplarily, part of the connecting member 232 is accommodated in the accommodating groove 2112, and the second material layer 2322 is located between the first material layer 2321 and the bottom surface of the accommodating groove 2112 in the thickness direction X of the wall. Of course, in other embodiments, the connecting member 232 may also be located entirely in the accommodating groove 2112.

[0198] In this embodiment, an accommodating groove 2112 for accommodating the connecting member 232 is provided on the side of the wall portion 211 facing away from the electrode assembly 22, so that on the one hand, the connecting member 232 can be assembled and positioned, 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 on the connecting member 232, so as to reduce the phenomenon of wear or damage of the connecting member 232 during use.

[0199] According to some embodiments of the present application, as shown in Figures 3 and 4, the housing 21 may include a shell 212 and an end cap 213. The shell 212 has an interior formed with an accommodating cavity having an opening 2121, which is used to accommodate the electrode assembly 22. The end cap 213 closes the opening 2121 and is a wall portion 211.

[0200] The end cover 213 is a wall portion 211 , that is, the electrode terminal 23 is mounted on the end cover 213 , and the mounting hole 2111 is provided on the end cover 213 .

[0201] In this embodiment, by setting the wall portion 211 of the outer shell 21 as the end cover 213 of the outer shell 21 for closing the opening 2121 of the shell 212, the battery cell 20 adopting this structure is convenient for assembling the electrode terminal 23 on the end cover 213, and is convenient for assembling and connecting the pole 231 of the electrode terminal 23 and the electrode assembly 22 with each other, which is beneficial to reducing the assembly difficulty of the battery cell 20 and improving the production efficiency of the battery cell 20.

[0202] 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 outer shell 21 may include a shell 212 and an end cap 213. The shell 212 includes an integrally formed side wall and a wall portion 211. The side wall is arranged around 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 is enclosed to form an opening 2121. The side wall and the wall portion 211 jointly define a receiving cavity for accommodating the electrode assembly 22, and the end cap 213 closes the opening 2121. In other words, the wall portion 211 is the bottom wall of the shell 212 arranged opposite the end cap 213 in the thickness direction X of the wall portion, that is, the electrode terminal 23 is mounted on the bottom wall of the shell 212, and the mounting hole 2111 is provided on the bottom wall of the shell 212.

[0203] The shell 212 includes an integrally formed side wall and wall portion 211 , that is, the shell 212 is manufactured using an integral molding process, such as an integral molding process such as stamping, casting or extrusion molding. In other words, the side wall and wall portion 211 of the shell 212 are an integral structure.

[0204] In this embodiment, by setting the wall portion 211 of the outer shell 21 as a wall of the shell 212 opposite to the end cover 213 in the thickness direction X of the wall portion, the battery cell 20 adopting this structure can make the area of ​​the outer shell 21 where the electrode terminal 23 is installed away from the end cover 213, and make there no direct connection relationship between the wall portion 211 and the end cover 213, thereby alleviating the phenomenon that the force generated when the electrode terminal 23 and other components pull or twist the wall portion 211 acts on the end cover 213, thereby reducing the risk of connection failure between the end cover 213 and the shell 212, and further helping to reduce the risk of leakage of the battery cell 20 during use.

[0205] According to some embodiments of the present application, the present application further provides a battery 100 , which includes the battery cell 20 of any of the above solutions.

[0206] As shown in FIG. 2 , the battery 100 may further include a box body 10 , in which the battery cells 20 are accommodated.

[0207] 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 jointly define an assembly space for accommodating the battery cells 20 .

[0208] Optionally, 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, and 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 can also 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.

[0209] Of course, the box body 10 formed by the first box body 11 and the second box body 12 can be in various shapes, such as a cylinder or a rectangular parallelepiped, etc. For example, in FIG2 , the box body 10 is a rectangular parallelepiped structure.

[0210] Optionally, the number of battery cells 20 disposed within the housing 10 may be one or more. For example, in FIG2 , the housing 10 of the battery 100 includes multiple battery cells 20, which may be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to a configuration in which multiple battery cells 20 are connected in both series and parallel. Multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid configuration, and then the entire structure formed by the multiple battery cells 20 is housed within the housing 10. Alternatively, the battery 100 may comprise multiple battery cells 20 that are first connected in series, in parallel, or in a hybrid configuration to form a battery module, which is then further connected in series, in parallel, or in a hybrid configuration to form a single structure, which is then housed within the housing 10.

[0211] It should be noted that in some embodiments, the battery 100 may not be provided with a housing 10. The battery 100 includes multiple battery cells 20, and the battery 100 composed of multiple battery cells 20 can be directly assembled on an electrical device to provide electrical energy to the electrical device through the multiple battery cells 20. In other words, the housing 10 can serve as part of the electrical device. Taking the vehicle 1000 as an example, the housing 10 can serve as part of the chassis structure of the vehicle 1000. For example, a portion of the housing 10 can form at least a portion of the floor of the vehicle 1000, or a portion of the housing 10 can form at least a portion of the crossbeam and longitudinal beam of the vehicle 1000.

[0212] According to some embodiments of the present application, as shown in FIG5 and FIG7 , the battery 100 further includes a current collecting component (not shown in the figures). The current collecting component is welded to the first material layer 2321 to electrically connect the current collecting component and the pole 231 .

[0213] The busbar component is welded to the first material layer 2321 of the connector 232 of the electrode terminal 23 so that the busbar component can be electrically connected to the electrode terminal 23 and to multiple battery cells 20, thereby realizing series or parallel connection between the multiple battery cells 20.

[0214] In this embodiment, the electrical connection between the busbar component and the electrode terminal 23 is achieved by welding the busbar component to the first material layer 2321 of the connector 232, thereby enabling the input or output of electrical energy from the battery cell 20 through the busbar component. Specifically, by configuring the connector 232 as a first material layer 2321 and a 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 in separation and isolation when the first material layer 2321 is welded to the busbar component for assembly. , in order to reduce the risk of the connector 232 being welded through and affecting other components, there is no need to reduce the risk of the connector 232 being welded through by increasing the thickness of the first material layer 2321. The battery cell 20 adopting 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 being assembled into a group, which is beneficial to improving the energy density of the battery 100 having such a battery cell 20.

[0215] In some embodiments, the material of the busbar component is the same as that of the first material layer 2321 .

[0216] It should be noted that the material of the first material layer 2321 is the same as the material of the convergence component, which means that the main component of the first material layer 2321 is the same as the main component of the convergence component. For example, if the first material layer 2321 and the convergence component are both made of a single material, such as aluminum, then the first material layer 2321 and the convergence component are composed of the same metal elements; if the first material layer 2321 and the convergence component are alloy materials or mixed materials, such as aluminum alloy, then the material of the first material layer 2321 and the convergence component is the same means that the main components of the first material layer 2321 and the convergence component are the same. If the first material layer 2321 and the convergence component only differ in the content of the components, then they are also the same material.

[0217] In this embodiment, by setting the material of the convergence component to be the same as the material of the first material layer 2321, it is possible to achieve a structure in which the convergence component and the first material layer 2321 are welded with the same material. On the one hand, it can reduce the difficulty of welding between the convergence component and the first material layer 2321. On the other hand, it can reduce the occurrence of cold welding or welding failure between the convergence component and the first material layer 2321, which is beneficial to improving the welding quality between the convergence component and the first material layer 2321.

[0218] According to some embodiments of the present application, the present application further 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 to the electrical device.

[0219] The electrical device may be any of the aforementioned devices or systems using the battery cell 20 .

[0220] According to some embodiments of the present application, as shown in Figures 3 to 6, the present application provides a battery cell 20, which includes a housing 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 housing 21 has a wall portion 211, and the wall portion 211 is provided with a mounting hole 2111. The mounting hole 2111 passes through the wall portion 211 along the thickness direction X of the wall portion. The housing 21 includes a shell 212 and an end cover 213. The interior of the shell 212 forms a receiving cavity with an opening 2121. 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 mounted on the wall portion 211. The electrode terminal 23 includes a post 231 and a connector 232. The post 231 includes a body 2311 and an abutment 2312. The body 2311 extends through the mounting hole 2111 along the wall's thickness direction X. The abutment 2312 abuts the side of the wall 211 facing the electrode assembly 22. The abutment 2312 is electrically connected to the tab 221 of the electrode assembly 22. The body 2311 and the abutment 2312 are integrally formed. Along the wall's thickness direction X, the connector 232 is located on the side of the wall 211 facing away from the electrode assembly 22. The end of the body 2311 facing 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, thereby securing the electrode terminal 23 to the wall 211. The connector 232 includes a first material layer 2321 and a second material layer 2322, stacked and compositely connected along the wall's thickness direction X. 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 2311 of the electrode post 231 and is used for welding to the current collector. The first material layer 2321 is made of the same material as the current collector, while the second material layer 2322 has a higher melting point than the first material layer 2321. The melting points of the first material layer 2321 and the second material layer 2322 are MP1 and MP2, respectively, satisfying MP2-MP1≥200°C. Along the wall's thickness direction X, 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 first material layer 2321 is made of aluminum, and the second material layer 2322 is made of steel. Along the wall thickness direction X, 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 wall thickness direction X, 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 electrode 231, with at least a portion of the seal 28 located within the mounting hole 2111. The seal 28 is sleeved around the outside of the body 2311 of the electrode 231, and is configured to seal the gap between the electrode 231 and the wall surface of the mounting hole 2111. Along the thickness direction X of the wall, a receiving groove 2112 is provided on the side of the wall 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 portion of the first insulating member 26 is received within the receiving groove 2112.

[0221] According to some embodiments of the present application, referring to Figures 3 to 4 and Figure 7, 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. The mounting hole 2111 penetrates the wall portion 211 along the thickness direction X of the wall portion. The housing 21 includes a shell 212 and an end cover 213. The interior of the shell 212 forms a receiving cavity with an opening 2121. 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 includes a post 231 and a connector 232. The post 231 includes a body 2311 and an abutment 2312. The body 2311 is disposed within the mounting hole 2111 along the wall thickness direction X. The abutment 2312 abuts against the side of the wall 211 facing the electrode assembly 22. The abutment 2312 is electrically connected to the tab 221 of the electrode assembly 22. The body 2311 and the abutment 2312 are integrally formed. Along the wall thickness direction X, the connector 232 is located on the side of the wall 211 facing away from the electrode assembly 22. The end of the body 2311 facing 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, thereby securing the electrode terminal 23 to the wall 211. The connector 232 includes a first material layer 2321 and a second material layer 2322, stacked and compositely connected along the wall's thickness direction X. 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 2311 of the electrode post 231 and is used for welding to the current collector. The first material layer 2321 is made of the same material as the current collector, while the second material layer 2322 has a higher melting point than the first material layer 2321. The melting points of the first material layer 2321 and the second material layer 2322 are MP1 and MP2, respectively, satisfying MP2-MP1≥200°C. Along the wall's thickness direction X, 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 first material layer 2321 is made of aluminum, and the second material layer 2322 is made of steel. The second material layer 2322 is welded to the wall portion 211, forming a weld mark that surrounds the outside of the mounting hole 2111. The second material layer 2322 is made of the same material as the wall portion 211. 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 portion of the connector 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.

[0222] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0223] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Persons skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection 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 or 2, characterized in that, 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 any one of claims 1-3, characterized in that, The first material layer and the second material layer are compositely connected.

5. The battery cell according to any one of claims 1-4, characterized in that, The material of the first material layer includes aluminum, and the material of the second material layer includes steel.

6. The battery cell according to any one of claims 1-5, characterized in that, 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, wherein 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, characterized in that, 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 or 10, characterized in that, 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 any one of claims 1-7, characterized in that, The second material layer is connected to the wall portion by welding.

13. The battery cell according to claim 12, wherein, 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 or 13, characterized in that, The material of the second material layer is the same as that of the wall portion.

15. The battery cell according to any one of claims 12-14, characterized in that, 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 any one of claims 1-15, 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 any one of claims 1-15, characterized in that, 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, characterized in that, The battery further includes: a current collecting component, which is welded to the first material layer to electrically connect the current collecting component and the pole post.

20. The battery according to claim 19, wherein, The material of the current collecting component is the same as that 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 electric energy.

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