Battery cell, battery, and electric device

Abstract

The present application relates to the technical field of batteries, and provides a battery cell, a battery, and an electric device. The battery cell comprises a casing assembly, an end cover, and an electrode assembly. An accommodating cavity having an opening is formed in the casing assembly; the casing assembly is provided with a first electrode lead-out part and a second electrode lead-out part; and in a first direction, the first electrode lead-out part and the second electrode lead-out part are both located at the end of the casing assembly distant from the opening. The end cover covers the opening. The electrode assembly is accommodated in the accommodating cavity; the electrode assembly comprises a main body part, a first tab, and a second tab; the polarities of the first tab and the second tab are opposite; the first tab and the second tab are both arranged at the end of the main body part facing away from the end cover in the first direction; and the first tab and the second tab are electrically connected to the first electrode lead-out part and the second electrode lead-out part, respectively. The end cover is provided with a pressure relief part, and the pressure relief part is configured to be able to relieve the internal pressure of the battery cell. Therefore, the difficulty in providing the pressure relief part on the battery cell can be reduced.

Description

Battery cells, batteries and electrical devices

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 2023111863282, filed on September 14, 2023, entitled “Battery Cell, Battery and Electrical Device,” the entire contents of which are incorporated herein by reference. Technical Field

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

[0004] New energy vehicles have experienced rapid growth in recent years. Within the electric vehicle sector, power batteries, as the power source, play an irreplaceable and important role. With the vigorous promotion of new energy vehicles, demand for power battery products is also growing. As core components of new energy vehicles, batteries have high requirements for operational reliability. Battery cells typically consist of a housing and an electrode assembly housed within the housing. However, existing battery cell manufacturing processes are challenging, hindering efficient production.

[0005] Summary of the Invention

[0006] The embodiments of the present application provide a battery cell, a battery, and an electrical device, which can effectively improve the production efficiency of the battery cell.

[0007] In a first aspect, an embodiment of the present application provides a battery cell, comprising a shell assembly, an end cover and an electrode assembly; a receiving cavity with an opening is formed inside the shell assembly, the shell assembly has a first electrode lead-out portion and a second electrode lead-out portion, along a first direction, the first electrode lead-out portion and the second electrode lead-out portion are both located at an end of the shell assembly away from the opening, the shell assembly comprises a shell and an electrode terminal, the shell comprises a first wall and a second wall, the second wall is arranged around the first wall, along the first direction, one end of the second wall is connected to the first wall, and the other end encloses the opening, the first wall and the second wall jointly enclose the receiving cavity, the electrode terminal is insulated and mounted on the first wall, the electrode terminal is the first electrode lead-out portion, and the first wall is the second electrode lead-out portion; the end cover covers the opening, and a pressure relief device is provided on the end cover. part, the pressure relief part is configured to release the internal pressure of the battery cell; the electrode assembly is accommodated in the accommodating cavity, the electrode assembly includes a main body, a first pole tab and a second pole tab, the polarity of the first pole tab and the second pole tab are opposite, the first pole tab and the second pole tab are both arranged at one end of the main body away from the end cover in the first direction, the first pole tab and the second pole tab are electrically connected to the first electrode lead-out portion and the second electrode lead-out portion, respectively; the first current collecting member is arranged between the first wall and the electrode assembly, the first current collecting member connects the first pole tab and the electrode terminal; wherein the main body is provided with a through hole, the through hole passes through both ends of the main body along the first direction, the first current collecting member is welded to the electrode terminal and forms a weld mark, and at least part of the projection of the weld mark along the first direction is located within the through hole.

[0008] In the above technical solution, by arranging the first and second tabs of the electrode assembly at the same end of the main body in the first direction, it is advantageous to save space occupied by the electrode assembly, thereby improving the energy density of a battery cell having such an electrode assembly. The battery cell includes a housing assembly and an end cap. The first and second electrode lead portions of the housing assembly, which are used to electrically connect to the first and second tabs of the electrode assembly, are both arranged at an end of the housing assembly away from the opening in the first direction. The end cap covers the opening, and a pressure relief portion is arranged on the end cap. The pressure relief portion provided on the end cap is located on the side of the electrode assembly away from the first and second tabs, and the end cap and the housing assembly are provided as separate structures. This facilitates reducing the difficulty of providing the pressure relief portion on the battery cell, thereby reducing the difficulty of manufacturing the battery cell and effectively improving the production efficiency of the battery cell. In which, the shell assembly is provided with a shell and an electrode terminal, the shell includes a first wall arranged opposite to the end cover in a first direction and a second wall arranged around the first wall, and the electrode terminal is insulated and installed on the first wall of the shell. By setting the electrode terminal as a first electrode lead-out portion electrically connected to the first pole tab, and setting the first wall as a second electrode lead-out portion electrically connected to the second pole tab, the electrode terminal and the first wall of the shell assembly are respectively used as output poles of the battery cell, so that the first electrode lead-out portion and the second electrode lead-out portion are both located at the end of the shell assembly away from the opening. The structure is simple, easy to implement, and can reduce the difficulty of assembling the battery cell. In addition, by arranging a first current collecting member between the first wall and the electrode assembly, and the first current collecting member connecting the first electrode tab and the electrode terminal to achieve electrical connection between the first electrode tab and the electrode terminal, it is helpful to reduce the difficulty of electrically connecting the first electrode tab and the electrode terminal to each other, and by arranging a through hole on the main body portion that passes through both ends of the main body portion along the first direction, and at least a part of the projection of the weld mark formed by the mutual welding connection of the first current collecting member and the electrode terminal in the first direction is set to be located within the through hole, so that the projection of the area where the first current collecting member and the electrode terminal overlap and are welded to each other can be located within the through hole, so that when the first current collecting member and the electrode terminal are welded, it can be seen from the opening of the shell. The first current collecting member and the electrode terminal are welded together through the through hole, thereby eliminating the need to perform penetration welding on the electrode terminal and the first current collecting member from the side of the first wall of the shell facing away from the electrode assembly, which is beneficial to reducing the welding difficulty and power required for welding between the first current collecting member and the electrode terminal. In addition, there is no need to reduce the thickness of the electrode terminal, locally thin the electrode terminal, or set the electrode terminal to a hollow structure in order to weld the first current collecting member and the electrode terminal from the side of the first wall of the shell facing away from the electrode assembly, which is beneficial to improving the structural strength of the electrode terminal and reducing the difficulty of processing the electrode terminal, thereby reducing the difficulty of manufacturing the battery cell and improving the production efficiency of the battery cell.

[0009] In some embodiments, the pressure relief portion is integrally formed with the end cover.

[0010] In the above technical solution, by setting the pressure relief part and the end cover as an integrally formed structure, the structural stability of the pressure relief part set on the end cover can be improved, which is conducive to reducing the risk of the pressure relief part falling off.

[0011] In some embodiments, the pressure relief portion and the end cover are provided separately.

[0012] In the above technical solution, by arranging the pressure relief part and the end cover as separate structures, the pressure relief part and the end cover are independent components, which is easy to assemble and helps optimize the production rhythm.

[0013] In some embodiments, the electrode assembly is a wound electrode assembly, and the through hole is a central hole of the main body.

[0014] In the above technical solution, by setting the electrode assembly as an electrode assembly with a wound structure, and making the center hole of the main body of the electrode assembly after winding a through hole, there is no need to set a through hole separately on the main body of the electrode assembly, which is beneficial to reducing the manufacturing difficulty of the battery cell and optimizing the production rhythm of the battery cell.

[0015] In some embodiments, the battery cell further includes a second current collecting member; the second current collecting member is disposed between the first wall and the electrode assembly, the second current collecting member is spaced apart from the first current collecting member, and the second current collecting member connects the second electrode tab and the first wall.

[0016] In the above technical solution, a second current collecting member is provided between the first wall and the electrode assembly, and the second current collecting member connects the second electrode tab and the first wall to achieve electrical connection between the second electrode tab and the first wall, thereby reducing the difficulty of electrically connecting the second electrode tab and the first wall. Furthermore, by spacing the first and second current collecting members apart, the risk of short circuits between the first and second current collecting members is reduced, thereby reducing the risk of battery cell use.

[0017] In some embodiments, the battery cell further includes a first insulating member; the first insulating member is disposed between the electrode assembly and the first wall, and the first insulating member insulates and isolates the first current collecting member from the second current collecting member.

[0018] In the above technical solution, a first insulating member is provided between the electrode assembly and the first wall, and the first insulating member is used to insulate and isolate the first current collecting member and the second current collecting member, thereby achieving insulation isolation between the first current collecting member and the second current collecting member, which is beneficial to further reduce the risk of short circuit between the first current collecting member and the second current collecting member.

[0019] In some embodiments, the first insulating member is provided with a first mounting hole and a second mounting hole arranged at intervals, the first current collecting member is provided in the first mounting hole, and the second current collecting member is provided in the second mounting hole.

[0020] In the above technical solution, by providing the first mounting holes and the second mounting holes arranged at intervals on the first insulating member, and the first current collecting member and the second current collecting member are respectively provided in the first mounting holes and the second mounting holes, on the one hand, the first current collecting member and the second current collecting member can be assembled to the first insulating member, so that the first insulating member can support and assemble the first current collecting member and the second current collecting member, which is conducive to reducing the difficulty of arranging the first current collecting member and the second current collecting member between the first wall and the electrode assembly. On the other hand, the first current collecting member and the second current collecting member can be arranged at intervals on the first insulating member to achieve insulation isolation between the first current collecting member and the second current collecting member.

[0021] In some embodiments, the first insulating member includes a first insulator and a second insulator; the first insulator is a ring structure; the second insulator is connected to the first insulator, and the second insulator is configured to separate the internal space of the first insulator into the first mounting hole and the second mounting hole, and the second insulator is located between the first current collecting component and the second current collecting component.

[0022] In the above technical solution, the first insulating member is provided with a first insulator of an annular structure and a second insulator connected to the inner side of the first insulator, and the second insulator is configured to divide the internal space of the first insulator into a first mounting hole and a second mounting hole, so that the first insulator and the second insulator jointly define the first mounting hole and the second mounting hole for assembling the first current collecting member and the second current collecting member. The first insulating member with such a structure can, on the one hand, be surrounded by the first insulator around the outer sides of the first current collecting member and the second current collecting member, so that the first current collecting member and the second current collecting member can be separated from the second wall of the shell, which is beneficial to reducing the risk of short circuit between the first current collecting member and the second current collecting member and the second wall of the shell. On the other hand, the first current collecting member and the second current collecting member can be separated by the second insulator, which is beneficial to reducing the risk of short circuit between the first current collecting member and the second current collecting member.

[0023] In some embodiments, along the first direction, a protrusion is provided on a side of the second current collecting member facing the first wall, and the protrusion is connected to the first wall.

[0024] In the above technical solution, a protrusion is provided on the side of the second current collecting component facing the first wall so that the second current collecting component is connected to the first wall through the protrusion, which helps to reduce the assembly difficulty between the first wall and the second current collecting component and improve the contact effect between the second current collecting component and the first wall.

[0025] In some embodiments, along the first direction, a groove is formed on a side of the second current collecting member facing away from the first wall and corresponding to the protrusion.

[0026] In the above technical solution, a groove is formed on the side of the second current collecting member away from the protrusion and in the area corresponding to the protrusion, so that the protrusion of the second current collecting member is a concave-convex structure that can be formed by stamping, so that the protrusion and the groove can be formed on both sides of the second current collecting member respectively. The current collecting member with this structure is easy to manufacture and is conducive to reducing the processing difficulty of the protrusion, so as to improve the processing efficiency of setting the protrusion on the second current collecting member.

[0027] In some embodiments, along the first direction, the first current collecting member has a first surface facing the first wall, the electrode terminal is connected to the first surface, and the second current collecting member has a second surface facing the first wall, and the protrusion is arranged on the second surface; wherein the first surface and the second surface are flush; or, along the first direction, the first surface is closer to the first wall than the second surface.

[0028] In the above technical solution, by setting the first surface of the first current collecting component to be flush with the second surface of the second current collecting component or closer to the first wall than the second surface of the second current collecting component, the protrusion set on the second surface of the second current collecting component can compensate for the gap between the second surface and the first wall, so that the second current collecting component can be connected to the first wall and the contact effect between the second current collecting component and the first wall can be improved.

[0029] In some embodiments, along the first direction, the first electrode tab has a third surface facing the first wall, the first current collecting member is connected to the third surface, the second electrode tab has a fourth surface facing the first wall, the second current collecting member is connected to the fourth surface; wherein the third surface is flush with the fourth surface.

[0030] In the above technical solution, by setting the third surface of the first electrode tab facing the first wall and the fourth surface of the second electrode tab facing the second wall to be flush with each other, on the one hand, it is convenient to process the first electrode tab and the second electrode tab, and on the other hand, it can achieve a structure in which the sides of the first current collecting member and the second current collecting member facing the electrode assembly in the first direction are flush with each other, so as to reduce the position difference between the first current collecting member and the second current collecting member in the first direction, thereby reducing the difficulty of assembling the first current collecting member and the second current collecting member between the electrode assembly and the first wall, and improving the internal space utilization of the battery cell.

[0031] In some embodiments, the first wall and the second wall are provided separately.

[0032] In the above technical solution, by setting the first wall and the second wall as a split structure, it is helpful to reduce the difficulty of assembling the electrode terminal on the first wall, and it is helpful to reduce the difficulty of assembling between the electrode terminal and the first pole ear and between the first wall and the second pole ear, thereby reducing the difficulty of manufacturing the battery cell and improving the production efficiency of the battery cell.

[0033] In some embodiments, the first wall and the second wall are integrally formed.

[0034] In the above technical solution, by setting the first wall and the second wall as an integrated structure, on the one hand, the connection stability and reliability between the first wall and the second wall can be improved, which is beneficial to improving the overall structural strength of the shell; on the other hand, the stress generated by the mutual assembly connection between the first wall and the second wall can be reduced. The impact of the stress on components such as the electrode terminal can be reduced.

[0035] In some embodiments, along the first direction, the thickness of the end cap is D1, satisfying 0.3 mm ≤ D1 ≤ 3.5 mm.

[0036] In the above technical solution, by setting the thickness of the end cap in the first direction to be greater than or equal to 0.3 mm, the end cap has sufficient structural strength, which helps reduce the risk of deformation or damage during use or assembly. It also provides sufficient space for the pressure relief portion to be installed on the end cap, which helps reduce the difficulty of installing the pressure relief portion on the end cap. In addition, by setting the thickness of the end cap in the first direction to be less than or equal to 3.5 mm, the space occupied by the end cap in the first direction is reduced, which helps to increase the energy density of the battery cell.

[0037] In some embodiments, the battery cell is cylindrical, and a central axis of the battery cell extends along the first direction.

[0038] In the above technical solution, by setting the battery cell to a cylindrical shape, it is easy to process the battery cell into a cylindrical structure, so that the battery cell has the advantages of high capacity, long cycle life, and a wide range of operating ambient temperatures.

[0039] In some embodiments, the diameter of the battery cell is D2, which satisfies 27 mm ≤ D2 ≤ 100 mm.

[0040] In the above technical solution, by setting the battery cell diameter to be greater than or equal to 27 mm, sufficient space is provided inside the battery cell to accommodate the electrode assembly, which helps reduce interference between the first and second tabs located at the same end of the main body of the electrode assembly. In addition, by setting the battery cell diameter to be less than or equal to 100 mm, the problem of excessive number of electrode plate layers in the electrode assembly caused by excessive internal space of the battery cell is alleviated, which helps reduce the stress accumulation caused by excessive number of electrode plate layers in the electrode assembly.

[0041] In a second aspect, an embodiment of the present application further provides a battery comprising the above-mentioned battery cell.

[0042] 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

[0043] 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.

[0044] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0045] FIG2 is an exploded view of the structure of a battery provided in some embodiments of the present application;

[0046] FIG3 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0047] FIG4 is an exploded view of the structure of a battery cell provided in some embodiments of the present application;

[0048] FIG5 is a schematic structural diagram of an electrode assembly of a battery cell provided in some embodiments of the present application;

[0049] FIG6 is a cross-sectional view of a battery cell provided in some embodiments of the present application;

[0050] FIG7 is a schematic diagram showing the connection between the first current collecting member and the second current collecting member of a battery cell provided in some embodiments of the present application, assembled on the first insulating member;

[0051] FIG8 is a schematic structural diagram of a first insulating member of a battery cell provided in some embodiments of the present application.

[0052] Icons: 1000-vehicle; 100-battery; 10-housing; 11-first housing; 12-second housing; 20-battery cell; 21-housing assembly; 211-accommodation cavity; 212-opening; 213-first electrode lead-out portion; 214-second electrode lead-out portion; 215-housing; 2151-first wall; 2151a-assembly hole; 2152-second wall; 216-electrode terminal; 22-end cap; 221-pressure relief portion; 222-score groove; 23-electrode assembly; 231-main body; 23 11-through hole; 232-first electrode ear; 2321-third surface; 233-second electrode ear; 2331-fourth surface; 24-second insulating member; 25-first current collecting member; 251-first surface; 26-weld stamp; 27-second current collecting member; 271-protrusion; 272-groove; 273-second surface; 28-first insulating member; 281-first mounting hole; 282-second mounting hole; 283-first insulator; 284-second insulator; 200-controller; 300-motor; X-first direction. DETAILED DESCRIPTION

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] The term "plurality" used in this application refers to two or more (including two).

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] 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.).

[0066] 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.

[0067] In some embodiments, a positive electrode may be a metal foam. The metal foam may be nickel foam, copper foam, aluminum foam, alloy foam, or carbon foam, among others. When a metal foam is used as the positive electrode, the surface of the metal foam may or may not be provided with a positive electrode active material. For example, a lithium source material, potassium metal, or sodium metal may be filled and / or deposited within the metal foam, where the lithium source material is lithium metal and / or a lithium-rich material.

[0068] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0069] As an example, the negative electrode current collector can be a metal foil, a metal foam, or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium can be used. The metal foam can be nickel foam, copper foam, aluminum foam, alloy foam, or carbon foam. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can 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.).

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0075] 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.

[0076] 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.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0082] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0083] 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.

[0084] 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.

[0085] As an example, a composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0086] 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.

[0087] In some embodiments, the electrode assembly may be cylindrical in shape.

[0088] 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.

[0089] 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.

[0090] As an example, the battery cells may be cylindrical battery cells, prismatic battery cells, pouch battery cells, or battery cells of other shapes.

[0091] 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.

[0092] 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.

[0093] 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.

[0094] 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.

[0095] In some embodiments, the battery may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0096] Batteries have outstanding advantages such as high energy density, low environmental pollution, high power density, long service life, wide adaptability and low self-discharge coefficient. They are an important part of the development of new energy today.

[0097] For a general battery cell, the battery cell usually includes a shell and an electrode assembly contained in the shell, the shell includes an end cover and an integrally formed shell, the end cover is covered on one end of the shell, and the electrode assembly is usually provided with a main body and positive and negative pole ears, the positive and negative pole ears are used to output or input the electric energy of the electrode assembly, in order to save the space occupied by the electrode assembly in the shell and to improve the energy density of the battery cell, especially in a battery cell with a cylindrical structure, in the related art, the positive and negative pole ears of the electrode assembly are usually arranged at the same end of the main body, and the electrode terminal is insulated and installed on the end cover, so that one of the positive and negative pole ears of the electrode assembly is welded to the electrode terminal, and the other is welded to the end cover, so as to output or input the positive and negative electrodes of the battery cell respectively through the end cover and the electrode terminal, thereby realizing a structure in which the electrode assembly has pole ears on the same side, so as to save the space occupied by the electrode assembly in the shell. However, in a battery cell of this structure, since the area of ​​the end cover is limited, the pressure relief portion for releasing the internal pressure of the battery cell is usually arranged on the bottom wall opposite to the shell and the end cover. As a result, it is difficult to arrange the pressure relief portion on the bottom wall, which makes the manufacturing of the battery cell more difficult and is not conducive to improving the production efficiency of the battery cell.

[0098] Based on the above considerations, in order to solve the problem of greater difficulty in the manufacturing process of battery cells, an embodiment of the present application provides a battery cell, which includes a shell assembly, an end cover and an electrode assembly. A accommodating cavity with an opening is formed inside the shell assembly, and the shell assembly has a first electrode lead-out portion and a second electrode lead-out portion. Along the first direction, the first electrode lead-out portion and the second electrode lead-out portion are both located at the end of the shell assembly away from the opening. The shell assembly includes a shell and an electrode terminal. The shell includes a first wall and a second wall. The second wall is arranged around the first wall. Along the first direction, one end of the second wall is connected to the first wall, and the other end is enclosed to form an opening. The first wall and the second wall are together enclosed to form a accommodating cavity. The electrode terminal is insulated and installed on the first wall. The electrode terminal is the first electrode lead-out portion, and the first wall is the second electrode lead-out portion. The end cover covers the opening, and a pressure relief portion is provided on the end cover. The pressure relief portion is configured to release the internal pressure of the battery cell. The electrode assembly is housed within the accommodating cavity and includes a main body, a first tab, and a second tab. The first tab and the second tab have opposite polarities and are disposed at an end of the main body facing away from the end cap in a first direction. The first tab and the second tab are electrically connected to the first and second electrode lead portions, respectively. A first current collecting member is disposed between the first wall and the electrode assembly, connecting the first tab and the electrode terminal. The main body is provided with a through-hole extending along the first direction through both ends of the main body. The first current collecting member is welded to the electrode terminal, forming a weld mark. At least a portion of the projection of the weld mark is located within the through-hole in the first direction.

[0099] In a battery cell of this structure, by arranging the first and second tabs of the electrode assembly at the same end of the main body in the first direction, it is advantageous to save space occupied by the electrode assembly, thereby improving the energy density of the battery cell having such an electrode assembly. The battery cell includes a housing assembly and an end cap. The first and second electrode lead portions of the housing assembly, which are used to electrically connect to the first and second tabs of the electrode assembly, are both arranged at an end of the housing assembly away from the opening in the first direction. The end cap covers the opening, and a pressure relief portion is arranged on the end cap. The pressure relief portion provided on the end cap is located on a side of the electrode assembly away from the first and second tabs, and the end cap and the housing assembly are provided as separate structures. This facilitates reducing the difficulty of providing the pressure relief portion on the battery cell, thereby reducing the difficulty of manufacturing the battery cell and effectively improving the production efficiency of the battery cell. In which, the shell assembly is provided with a shell and an electrode terminal, the shell includes a first wall arranged opposite to the end cover in a first direction and a second wall arranged around the first wall, and the electrode terminal is insulated and installed on the first wall of the shell. By setting the electrode terminal as a first electrode lead-out portion electrically connected to the first pole tab, and setting the first wall as a second electrode lead-out portion electrically connected to the second pole tab, the electrode terminal and the first wall of the shell assembly are respectively used as output poles of the battery cell, so that the first electrode lead-out portion and the second electrode lead-out portion are both located at the end of the shell assembly away from the opening. The structure is simple, easy to implement, and can reduce the difficulty of assembling the battery cell.

[0100] In addition, by arranging a first current collecting member between the first wall and the electrode assembly, and the first current collecting member connecting the first electrode tab and the electrode terminal to achieve electrical connection between the first electrode tab and the electrode terminal, it is helpful to reduce the difficulty of electrically connecting the first electrode tab and the electrode terminal to each other, and by arranging a through hole on the main body portion that passes through both ends of the main body portion along the first direction, and at least a part of the projection of the weld mark formed by the mutual welding connection of the first current collecting member and the electrode terminal in the first direction is set to be located within the through hole, so that the projection of the area where the first current collecting member and the electrode terminal overlap and are welded to each other can be located within the through hole, so that when the first current collecting member and the electrode terminal are welded, it can be seen from the opening of the shell. The first current collecting member and the electrode terminal are welded together through the through hole, thereby eliminating the need to perform penetration welding on the electrode terminal and the first current collecting member from the side of the first wall of the shell facing away from the electrode assembly, which is beneficial to reducing the welding difficulty and power required for welding between the first current collecting member and the electrode terminal. In addition, there is no need to reduce the thickness of the electrode terminal, locally thin the electrode terminal, or set the electrode terminal to a hollow structure in order to weld the first current collecting member and the electrode terminal from the side of the first wall of the shell facing away from the electrode assembly, which is beneficial to improving the structural strength of the electrode terminal and reducing the difficulty of processing the electrode terminal, thereby reducing the difficulty of manufacturing the battery cell and improving the production efficiency of the battery cell.

[0101] 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 can help reduce the difficulty of providing a pressure relief portion on the battery cells, thereby reducing the difficulty of manufacturing the battery cells and effectively improving the production efficiency of the battery cells.

[0102] 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.

[0103] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0104] 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.

[0105] 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.

[0106] 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 .

[0107] 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.

[0108] 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.

[0109] In the battery 100, there may 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 may be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to multiple battery cells 20 being 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. Of course, in some embodiments, the battery 100 may also be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid configuration to form a battery module. The multiple battery modules are then connected in series, in parallel, or in a hybrid configuration to form a single structure, which is then housed within the housing 10.

[0110] 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 .

[0111] 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 the battery cells 20 are not limited thereto. The battery cells 20 can be cylindrical, prismatic, or other shapes. For example, in FIG3 , the battery cells 20 are cylindrical.

[0112] According to some embodiments of the present application, with reference to FIG3 , and further with reference 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 schematic structural diagram of an electrode assembly 23 of a battery cell 20 provided in some embodiments of the present application, and FIG6 is a cross-sectional view of a battery cell 20 provided in some embodiments of the present application. The present application provides a battery cell 20, which includes a shell assembly 21, an end cover 22 and an electrode assembly 23. A accommodating cavity 211 with an opening 212 is formed inside the shell assembly 21. The shell assembly 21 has a first electrode lead-out portion 213 and a second electrode lead-out portion 214. Along the first direction X, the first electrode lead-out portion 213 and the second electrode lead-out portion 214 are both located at an end of the shell assembly 21 away from the opening 212, and the end cover 22 covers the opening 212. The electrode assembly 23 is housed within the accommodating cavity 211 and includes a main body 231, a first electrode tab 232, and a second electrode tab 233. The first electrode tab 232 and the second electrode tab 233 have opposite polarities and are disposed at one end of the main body 231 facing away from the end cap 22 in the first direction X. The first electrode tab 232 and the second electrode tab 233 are electrically connected to the first electrode lead portion 213 and the second electrode lead portion 214, respectively. A pressure relief portion 221 is disposed on the end cap 22 to relieve internal pressure in the battery cell 20.

[0113] The housing assembly 21 includes a housing 215. The housing 215 and the end cap 22 together form the outer shell of the battery cell 20. The housing can also be used to accommodate electrolyte, such as electrolyte solution. The housing 215 has a chamber 211 formed within it. The chamber 211 is used to accommodate the electrode assembly 23, and the chamber 211 has an opening 212. The end cap 22 covers the opening 212 of the housing 215 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 23 and the electrolyte. Optionally, the housing 215 and the end cap 22 can be made of a variety of materials, for example, copper, iron, aluminum, steel, or an aluminum alloy.

[0114] When assembling the battery cell 20 , the electrode assembly 23 may be placed in the housing 215 and filled with electrolyte. The end cap 22 may then be placed on the opening 212 of the housing 215 to complete the assembly of the battery cell 20 .

[0115] The housing 215 of the housing assembly 21 can have a variety of shapes, such as a cylindrical or prismatic structure. The shape of the housing 215 can be determined based on the specific shape of the electrode assembly 23. For example, if the electrode assembly 23 has a cylindrical structure, a cylindrical housing 215 can be selected. Of course, the end cap 22 can also have a variety of structures, such as a plate-like structure or a hollow structure with one end open. For example, in Figures 3 and 4, the housing 215 has a cylindrical structure, and the central axis of the housing 215 extends along the first direction X.

[0116] Along the first direction X, the first electrode lead-out portion 213 and the second electrode lead-out portion 214 are both located at one end of the shell assembly 21 away from the opening 212, that is, the first electrode lead-out portion 213 and the second electrode lead-out portion 214 are both located at one end of the electrode assembly 23 in the first direction X, and the end cover 22 is located at the other end of the electrode assembly 23 in the first direction X, so that the end cover 22 for setting the pressure relief portion 221 and the first electrode lead-out portion 213 and the second electrode lead-out portion 214 for electrically connecting to the first pole ear 232 and the second pole ear 233 of the electrode assembly 23 are respectively located at the two ends of the electrode assembly 23 in the first direction X.

[0117] The first electrode lead-out portion 213 and the second electrode lead-out portion 214 are used to input or output electrical energy from the battery cell 20. The first electrode lead-out portion 213 and the second electrode lead-out portion 214 are respectively used to output or input the positive and negative electrodes of the battery cell 20. The first electrode lead-out portion 213 and the second electrode lead-out portion 214 can have various structures. For example, in Figures 3 and 4, the housing 215 can include a first wall 2151 and a second wall 2152. Along the first direction X, the first wall 2151 is arranged opposite the end cap 22, and the second wall 2152 is arranged around the first wall 2151. One end of the second wall 2152 in the first direction X is connected to the first wall 2151, and the other end encloses an opening 212 for the end cap 22 to cover. Correspondingly, the housing assembly 21 may further include an electrode terminal 216, which is insulated and mounted on the first wall 2151. That is, there is no electrical connection between the electrode terminal 216 and the first wall 2151. The electrode terminal 216 serves as the first electrode lead portion 213 for electrically connecting to the first electrode tab 232, and the first wall 2151 serves as the second electrode lead portion 214 for electrically connecting to the second electrode tab 233. The first direction X is the thickness direction of the first wall 2151 and the thickness direction of the end cap 22.

[0118] It should be noted that, in some embodiments, the first electrode lead-out portion 213 may also be the first wall 2151, and correspondingly, the second electrode lead-out portion 214 is the electrode terminal 216. Of course, the structure of the battery cell 20 is not limited to this. In other embodiments, the battery cell 20 may also have other structures. For example, two electrode terminals 216 may be insulated and installed on the first wall 2151. The two electrode terminals 216 are arranged at intervals, that is, the two electrode terminals 216 do not contact each other, and the two electrode terminals 216 are respectively the first electrode lead-out portion 213 and the second electrode lead-out portion 214.

[0119] The end cover 22 covers the opening 212, that is, the end cover 22 and the shell assembly 21 are separately arranged structures, and the end cover 22 is connected to the opening 212 of the shell 215 of the shell assembly 21. Optionally, the structure in which the end cover 22 is connected to the shell assembly 21 can be various. For example, the end cover 22 can be connected to the opening 212 of the shell 215 of the shell assembly 21 by welding or bonding.

[0120] Optionally, the first wall 2151 and the second wall 2152 of the shell 215 can be an integrally formed structure, that is, the first wall 2151 and the second wall 2152 are an integral structure made by an integral forming process such as stamping or casting. The first wall 2151 and the second wall 2152 of the shell 215 can also be a split structure, that is, the first wall 2151 and the second wall 2152 are split structures, and the first wall 2151 can be connected to one end of the second wall 2152 in the first direction X by welding or bonding.

[0121] For example, in Figure 4, the first wall 2151 and the second wall 2152 of the shell 215 are separately arranged structures. It should be noted that, in this embodiment, the electrode assembly 23 can be first assembled to the inside of the second wall 2152, and after the second wall 2152 and the first wall 2151 are connected to each other, the end cover 22 can be covered on the opening 212 of the second wall 2152.

[0122] It should be noted that the electrode assembly 23 is a component in the battery cell 20 where electrochemical reactions occur. The structure of the electrode assembly 23 can be various. For example, the electrode assembly 23 can be a wound structure formed by winding a positive electrode sheet, an isolation member and a negative electrode sheet, and the main body 231 of the electrode assembly 23 is cylindrical, and the central axis of the main body 231 extends along the first direction X.

[0123] 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.

[0124] Among them, the main body 231 is the area where the electrode assembly 23 undergoes chemical reactions within the battery cell 20. The main body 231 is a structure formed by winding the area of ​​the positive electrode sheet coated with the positive electrode active material layer, the isolation member and the area of ​​the negative electrode sheet coated with the negative electrode active material layer. It mainly works by moving metal ions between the positive electrode sheet and the negative electrode sheet with opposite polarities.

[0125] The first electrode tab 232 and the second electrode tab 233 are both arranged at an end of the main body 231 away from the end cover 22 in the first direction X. That is, the first electrode tab 232 and the second electrode tab 233 are arranged at the same end of the main body 231 in the first direction X and are located at the end of the main body 231 facing the first wall 2151.

[0126] The first electrode tab 232 and the second electrode tab 233 are respectively used to output or input the positive and negative electrodes of the electrode assembly 23. If the first electrode tab 232 is used to input or output the positive electrode of the electrode assembly 23, the first electrode tab 232 is formed by laminating and connecting the regions of the positive electrode sheets not coated with the positive electrode active material layer. Correspondingly, if the second electrode tab 233 is used to output or input the negative electrode of the electrode assembly 23, the second electrode tab 233 is formed by laminating and connecting the regions of the negative electrode sheets not coated with the negative electrode active material layer. If the first electrode tab 232 is used to output or input the negative electrode of the electrode assembly 23, the first electrode tab 232 is formed by laminating and connecting the regions of the negative electrode sheets not coated with the negative electrode active material layer. Correspondingly, if the second electrode tab 233 is used to input or output the positive electrode of the electrode assembly 23, the second electrode tab 233 is formed by laminating and connecting the regions of the positive electrode sheets not coated with the positive electrode active material layer. Illustratively, in the embodiment of the present application, the first electrode tab 232 is used to output or input the negative electrode of the electrode assembly 23 , and the second electrode tab 233 is used to output or input the positive electrode of the electrode assembly 23 .

[0127] A pressure relief portion 221 is provided on the end cover 22, and the pressure relief portion 221 is configured to release the internal pressure of the battery cell 20. That is, the pressure relief portion 221 is provided on the end cover 22 of the battery cell 20. The pressure relief portion 221 plays the role of releasing the internal pressure of the battery cell 20 when the battery cell 20 has thermal runaway. The pressure relief portion 221 and the end cover 22 can be an integrally formed structure or a separately arranged structure.

[0128] 4 and 6 , the pressure relief portion 221 and the end cap 22 are integrally formed, and the pressure relief portion 221 is a region of the end cap 22 where a weak structure is formed. For example, the end cap 22 is provided with a notched groove 222, and the pressure relief portion 221 is the region of the end cap 22 where the notched groove 222 is provided. Of course, in other embodiments, the pressure relief portion 221 and the end cap 22 may also be separate structures, and the pressure relief portion 221 may be connected to the end cap 22 by welding or other means. Correspondingly, the pressure relief portion 221 may be a component such as an explosion-proof valve, an explosion-proof disk, an air valve, a pressure relief valve, or a safety valve.

[0129] By arranging the first tab 232 and the second tab 233 of the electrode assembly 23 at the same end of the main body 231 in the first direction X, it is beneficial to save the space occupied by the electrode assembly 23 and improve the energy density of the battery cell 20 having such an electrode assembly 23. Among them, the battery cell 20 includes a shell assembly 21 and an end cover 22. The first electrode lead-out portion 213 and the second electrode lead-out portion 214 of the shell assembly 21 for electrically connecting to the first pole ear 232 and the second pole ear 233 of the electrode assembly 23 are both arranged at one end of the shell assembly 21 away from the opening 212 in the first direction X. The end cover 22 covers the opening 212 and the pressure relief portion 221 is arranged on the end cover 22, so that the pressure relief portion 221 arranged on the end cover 22 is a structure located on the side of the electrode assembly 23 away from the first pole ear 232 and the second pole ear 233, and the end cover 22 and the shell assembly 21 are separately arranged structures, which is conducive to reducing the difficulty of setting the pressure relief portion 221 on the battery cell 20, thereby reducing the manufacturing difficulty of the battery cell 20, and thus effectively improving the production efficiency of the battery cell 20.

[0130] According to some embodiments of the present application, referring to FIG. 4 , the pressure relief portion 221 and the end cover 22 are integrally formed, that is, the pressure relief portion 221 and the end cover 22 are an integrated structure.

[0131] Among them, the pressure relief portion 221 is integrally formed with the end cover 22, that is, the pressure relief portion 221 is a weak structure formed on the end cover 22 through an integral molding process, such as stamping or etching. For example, a notched groove 222 is provided on the end cover 22, and the area where the notched groove 222 is provided on the end cover 22 is the pressure relief portion 221.

[0132] By providing the pressure relief portion 221 and the end cover 22 as an integrally formed structure, the structural stability of the pressure relief portion 221 provided on the end cover 22 can be improved, which is beneficial to reducing the risk of the pressure relief portion 221 falling off or connection failure.

[0133] It should be noted that in some embodiments, the battery cell 20 may also have other structures. For example, the pressure relief portion 221 and the end cap 22 are provided separately. In other words, the pressure relief portion 221 and the end cap 22 are two independent components, and the pressure relief portion 221 can be connected to the end cap 22 by welding or other methods. By providing the pressure relief portion 221 and the end cap 22 as separate structures, the pressure relief portion 221 and the end cap 22 are independent components, which facilitates assembly and helps optimize production cycle time. For example, the pressure relief portion 221 can be a pressure relief component such as an explosion-proof valve, explosion-proof disk, air valve, pressure relief valve, or safety valve.

[0134] According to some embodiments of the present application, as shown in Figures 3, 4, and 6, the housing assembly 21 may include a housing 215 and an electrode terminal 216. The housing 215 may include a first wall 2151 and a second wall 2152. The second wall 2152 is disposed around the first wall 2151. Along the first direction X, one end of the second wall 2152 is connected to the first wall 2151, and the other end encloses an opening 212. The first wall 2151 and the second wall 2152 together enclose a receiving cavity 211. The electrode terminal 216 is insulated and mounted on the first wall 2151. The electrode terminal 216 serves as the first electrode lead-out portion 213, and the first wall 2151 serves as the second electrode lead-out portion 214.

[0135] In which, the second wall 2152 is arranged around the first wall 2151, that is, the second wall 2152 is an annular structure extending along the circumference of the first wall 2151, so that the second wall 2152 is a side wall surrounding the outer peripheral side of the electrode assembly 23, so that the shell 215 is a hollow structure with an opening 212 formed at one end in the first direction X, and the interior of the shell 215 forms a accommodating cavity 211 for accommodating the electrode assembly 23.

[0136] The electrode terminal 216 is the first electrode lead-out portion 213, and the first wall 2151 is the second electrode lead-out portion 214. That is, the electrode terminal 216 of the shell assembly 21 is electrically connected to the first pole ear 232 of the electrode assembly 23, and the first wall 2151 of the shell 215 of the shell assembly 21 is electrically connected to the second pole ear 233 of the electrode assembly 23, so that the electrode terminal 216 and the first wall 2151 respectively output or input the positive and negative poles of the battery cell 20.

[0137] The electrode terminal 216 serves to output or input electrical energy of the battery cell 20 . The electrode terminal 216 may be made of various materials. For example, the electrode terminal 216 may be made of copper, iron, aluminum, steel, or aluminum alloy.

[0138] The electrode terminal 216 is insulated and mounted on the first wall 2151 , that is, no electrical connection is formed between the electrode terminal 216 and the first wall 2151 .

[0139] In some embodiments, in Figure 6, an assembly hole 2151a is provided on the first wall 2151, and the assembly hole 2151a passes through both sides of the first wall 2151 along the first direction X. The electrode terminal 216 is passed through the assembly hole 2151a, and the assembly holes 2151a are extended from both ends of the electrode terminal 216 in the first direction X, so that the two ends of the electrode terminal 216 in the first direction X protrude from both sides of the first wall 2151 respectively, so that one end of the electrode terminal 216 facing the electrode assembly 23 in the first direction X can be electrically connected to the first pole ear 232, and the other end can be electrically connected to the busbar component of the battery 100.

[0140] The battery cell 20 may further include a second insulating member 24 , which is disposed between the first wall 2151 and the electrode terminal 216 to insulate and isolate the first wall 2151 from the electrode terminal 216 , thereby achieving an insulated installation of the electrode terminal 216 on the first wall 2151 .

[0141] For example, the second insulating member 24 can be made of various materials, such as rubber, plastic, or silicone.

[0142] The shell assembly 21 is provided with a shell 215 and an electrode terminal 216. The shell 215 includes a first wall 2151 arranged opposite to the end cover 22 in the first direction X and a second wall 2152 surrounding the first wall 2151. The electrode terminal 216 is insulated and installed on the first wall 2151 of the shell 215. By setting the electrode terminal 216 as the first electrode lead-out portion 213 electrically connected to the first pole tab 232, and setting the first wall 2151 as the second electrode lead-out portion 214 electrically connected to the second pole tab 233, the electrode terminal 216 and the first wall 2151 of the shell assembly 21 are respectively used as the output poles of the battery cell 20, so that the first electrode lead-out portion 213 and the second electrode lead-out portion 214 are both located at the end of the shell assembly 21 away from the opening 212. The structure is simple, easy to implement, and can reduce the difficulty of assembling the battery cell 20.

[0143] According to some embodiments of the present application, as shown in Figures 4, 5 and 6, the battery cell 20 may further include a first current collecting member 25, which is disposed between the first wall 2151 and the electrode assembly 23, and the first current collecting member 25 connects the first electrode tab 232 and the electrode terminal 216.

[0144] In which, along the first direction X, the first current collecting member 25 is arranged between the first wall 2151 and the electrode assembly 23, and both sides of the first current collecting member 25 are respectively connected to the first electrode tab 232 and the electrode terminal 216 to achieve electrical connection between the first electrode tab 232 and the electrode terminal 216.

[0145] Optionally, the connection structure between the first current collecting member 25 and the first electrode tab 232 can be various, such as welding, abutting or clamping. Similarly, the connection structure between the first current collecting member 25 and the electrode terminal 216 can also be various, such as welding, abutting or clamping.

[0146] The first current collecting member 25 serves to electrically connect the first electrode tab 232 and the electrode terminal 216 . The first current collecting member 25 can be made of various materials, for example, copper, iron, aluminum, steel, or aluminum alloy.

[0147] By arranging the first current collecting member 25 between the first wall 2151 and the electrode assembly 23, and the first current collecting member 25 connecting the first electrode tab 232 and the electrode terminal 216, an electrical connection between the first electrode tab 232 and the electrode terminal 216 is achieved, which helps to reduce the difficulty of electrically connecting the first electrode tab 232 and the electrode terminal 216 to each other.

[0148] According to some embodiments of the present application, as shown in Figures 4, 5, and 6, a through hole 2311 is provided on the main body 231. The through hole 2311 passes through both ends of the main body 231 along the first direction X. The first current collecting member 25 is welded to the electrode terminal 216 to form a weld mark 26. At least a portion of the projection of the weld mark 26 along the first direction X is located within the through hole 2311.

[0149] The through hole 2311 passes through both ends of the main body 231 along the first direction X. That is, the main body 231 of the electrode assembly 23 is provided with a through hole 2311 passing through both ends of the main body 231 in the first direction X.

[0150] The first current collecting member 25 and the electrode terminal 216 are welded to form a weld mark 26 . That is, the first current collecting member 25 and the electrode terminal 216 are welded to each other, and a weld mark 26 is formed in the welded area.

[0151] Along the first direction X, at least a portion of the projection of the weld mark 26 lies within the through-hole 2311. This means that the first current collecting member 25 and the electrode terminal 216 have a region where they overlap and are welded in the first direction X, and at least a portion of the projection of the welded region in the first direction X lies within the through-hole 2311. In other words, the region where the first current collecting member 25 and the electrode terminal 216 are welded in the first direction X corresponds to the through-hole 2311. This allows welding equipment to penetrate the through-hole 2311 from the end of the through-hole 2311 proximal to the end cap 22 in the first direction X, and then weld the first current collecting member 25 and the electrode terminal 216 from the side of the first current collecting member 25 facing away from the electrode terminal 216. This eliminates the need for the electrode terminal 216 to be hollow or partially thinned, effectively increasing the thickness of the electrode terminal 216. For example, in FIG. 6 , the electrode member 25 is shown as a hollow structure. However, in other embodiments, the electrode terminal 216 may also be a solid structure.

[0152] It should be noted that the projection of the weld mark 26 formed by the weld connection between the first current collecting member 25 and the electrode terminal 216 in the first direction X may be entirely located within the through-hole 2311, or may be only partially located within the through-hole 2311. For example, in FIG6 , the projection of the weld mark 26 formed by the weld connection between the first current collecting member 25 and the electrode terminal 216 in the first direction X is entirely located within the through-hole 2311.

[0153] By providing a through hole 2311 on the main body 231 that passes through both ends of the main body 231 along the first direction X, and at least a portion of the projection of the weld mark 26 formed by the first current collecting member 25 and the electrode terminal 216 being welded to each other in the first direction X is arranged to be located within the through hole 2311, so that the projection of the area where the first current collecting member 25 and the electrode terminal 216 overlap and are welded to each other in the first direction X can be located within the through hole 2311. When welding the first current collecting member 25 and the electrode terminal 216, the first current collecting member 25 and the electrode terminal 216 can be welded to each other through the through hole 2311 from the opening 212 of the housing 215, without having to deviate from the first wall 2151 of the housing 215. The electrode terminal 216 and the first current collecting member 25 are penetrated and welded on one side of the electrode assembly 23, which is beneficial to reducing the welding difficulty and the power required for welding between the first current collecting member 25 and the electrode terminal 216. There is no need to reduce the thickness of the electrode terminal 216 or locally thin the electrode terminal 216 or set the electrode terminal 216 to a hollow structure in order to weld the first current collecting member 25 and the electrode terminal 216 from the first wall 2151 of the shell 215 away from the side of the electrode assembly 23, which is beneficial to improving the structural strength of the electrode terminal 216 and reducing the processing difficulty of the electrode terminal 216, thereby reducing the manufacturing difficulty of the battery cell 20 and improving the production efficiency of the battery cell 20.

[0154] In some embodiments, as shown in FIG. 5 and FIG. 6 , the electrode assembly 23 is a wound electrode assembly 23 , and the through hole 2311 is a central hole of the main body 231 .

[0155] The through hole 2311 is the central hole of the main body 231 , that is, the through hole 2311 is the central channel formed by the positive electrode sheet, the negative electrode sheet and the separator of the main body 231 being wound together.

[0156] By setting the electrode assembly 23 as an electrode assembly 23 with a wound structure, and making the center hole of the main body 231 of the electrode assembly 23 after winding a through hole 2311, there is no need to set the through hole 2311 separately on the main body 231 of the electrode assembly 23, which is beneficial to reducing the manufacturing difficulty of the battery cell 20 and optimizing the production rhythm of the battery cell 20.

[0157] According to some embodiments of the present application, as shown in Figures 4, 5 and 6, the battery cell 20 may further include a second current collecting member 27, which is arranged between the first wall 2151 and the electrode assembly 23, and the second current collecting member 27 is spaced apart from the first current collecting member 25, and the second current collecting member 27 connects the second electrode tab 233 and the first wall 2151.

[0158] In which, along the first direction X, the second current collecting member 27 is arranged between the first wall 2151 and the electrode assembly 23, and both sides of the second current collecting member 27 are respectively connected to the second electrode tab 233 and the first wall 2151 to achieve electrical connection between the second electrode tab 233 and the first wall 2151.

[0159] Optionally, the connection structure between the second current collecting member 27 and the second electrode tab 233 can be various, such as welding, abutting or clamping. Similarly, the connection structure between the second current collecting member 27 and the first electrical wall 2151 can be various, such as welding, abutting or clamping.

[0160] The second current collecting member 27 serves to electrically connect the second electrode tab 233 and the first wall 2151 . The second current collecting member 27 can be made of various materials, for example, copper, iron, aluminum, steel, or aluminum alloy.

[0161] By disposing the second current collecting member 27 between the first wall 2151 and the electrode assembly 23, and by connecting the second electrode tab 233 and the first wall 2151, an electrical connection is achieved between the second electrode tab 233 and the first wall 2151. This helps reduce the difficulty of electrically connecting the second electrode tab 233 and the first wall 2151. In addition, by spacing the first current collecting member 25 and the second current collecting member 27 apart, the short circuit between the first current collecting member 25 and the second current collecting member 27 is reduced, thereby reducing the risk of using the battery cell 20.

[0162] According to some embodiments of the present application, referring to Figures 4 and 6, and further referring to Figures 7 and 8, Figure 7 is a schematic diagram of the connection of the first current collecting member 25 and the second current collecting member 27 of the battery cell 20 provided in some embodiments of the present application, and Figure 8 is a schematic diagram of the structure of the first insulating member 28 of the battery cell 20 provided in some embodiments of the present application. The battery cell 20 may also include a first insulating member 28, which is disposed between the electrode assembly 23 and the first wall 2151. The first insulating member 28 insulates and separates the first current collecting member 25 from the second current collecting member 27.

[0163] The first insulating member 28 provides insulation for the first current collecting member 25 and the second current collecting member 27 . The first insulating member 28 may be made of rubber, silicone, plastic, or the like.

[0164] The first insulating member 28 insulates and isolates the first current collecting member 25 and the second current collecting member 27. That is, at least a portion of the first insulating member 28 is located between the first current collecting member 25 and the second current collecting member 27 so that the first current collecting member 25 and the second current collecting member 27 do not contact each other. That is, the first insulating member 28 can separate the first current collecting member 25 and the second current collecting member 27.

[0165] By arranging a first insulating member 28 between the electrode assembly 23 and the first wall 2151, and the first insulating member 28 is used to insulate and isolate the first current collecting member 25 and the second current collecting member 27, it is possible to achieve insulation isolation between the first current collecting member 25 and the second current collecting member 27, which is beneficial to further reduce the risk of short circuit between the first current collecting member 25 and the second current collecting member 27.

[0166] In some embodiments, as shown in Figures 6, 7 and 8, the first insulating member 28 is provided with first mounting holes 281 and second mounting holes 282 arranged at intervals, the first current collecting member 25 is provided in the first mounting hole 281, and the second current collecting member 27 is provided in the second mounting hole 282.

[0167] Among them, the first insulating member 28 is provided with a first mounting hole 281 and a second mounting hole 282 arranged at intervals, that is, the first mounting hole 281 and the second mounting hole 282 provided on the first insulating member 28 do not contact each other, so that the first insulating member 28 can also provide an assembly function for the first current collecting component 25 and the second current collecting component 27. As shown in Figure 8, the first mounting hole 281 and the second mounting hole 282 are both structures that pass through both sides of the first insulating member 28 in the first direction X.

[0168] For example, the first current collecting component 25 is snapped into the first mounting hole 281. Of course, in other embodiments, the first current collecting component 25 can also be connected to the first mounting hole 281 by bonding or bolting. Similarly, the second current collecting component 27 is snapped into the second mounting hole 282. Of course, in other embodiments, the second current collecting component 27 can also be connected to the second mounting hole 282 by bonding or bolting.

[0169] By providing the first mounting holes 281 and the second mounting holes 282 arranged at intervals on the first insulating member 28, and the first current collecting member 25 and the second current collecting member 27 being respectively provided in the first mounting holes 281 and the second mounting holes 282, on the one hand, the first current collecting member 25 and the second current collecting member 27 can be assembled to the first insulating member 28, so that the first insulating member 28 can support and assemble the first current collecting member 25 and the second current collecting member 27, which is conducive to reducing the difficulty of arranging the first current collecting member 25 and the second current collecting member 27 between the first wall 2151 and the electrode assembly 23. On the other hand, the first current collecting member 25 and the second current collecting member 27 can be arranged at intervals on the first insulating member 28 to achieve insulation isolation between the first current collecting member 25 and the second current collecting member 27, thereby effectively reducing the risk of short circuit between the first current collecting member 25 and the second current collecting member 27.

[0170] In some embodiments, as shown in Figures 7 and 8, the first insulating member 28 may include a first insulator 283 and a second insulator 284. The first insulator 283 is an annular structure. The second insulator 284 is connected to the first insulator 283 and is configured to separate the interior space of the first insulator 283 into a first mounting hole 281 and a second mounting hole 282. The second insulator 284 is located between the first current collecting member 25 and the second current collecting member 27.

[0171] Among them, the first insulator 283 is a ring structure, that is, the first insulator 283 is a ring structure connected end to end. The shape of the first insulator 283 can be various. For example, referring to Figures 7 and 8, the first insulator 283 is a circular ring structure, and the first insulator 283 surrounds the outside of the first current collecting component 25 and the second current collecting component 27. That is, the first insulator 283 is a ring structure, and the first current collecting component 25 and the second current collecting component 27 are both located on the inner side of the first insulator 283.

[0172] The second insulator 284 is connected to the first insulator 283. The second insulator 284 is configured to separate the internal space of the first insulator 283 into a first mounting hole 281 and a second mounting hole 282. The second insulator 284 is located between the first current collecting member 25 and the second current collecting member 27. That is, the second insulator 284 is located on the inner side of the first insulator 283, and both ends of the second insulator 284 are connected to the inner circumferential surface of the first insulator 283 to separate the internal space of the first insulator 283 into two assembly spaces, namely the first mounting hole 281 and the second mounting hole 282.

[0173] Optionally, the first insulator 283 and the second insulator 284 can be an integrally formed structure or a separately provided structure. For example, in FIG8 , the first insulator 283 and the second insulator 284 are an integrally formed structure, and the first insulator 283 and the second insulator 284 can be manufactured by an integral molding process such as injection molding, stamping, or extrusion molding.

[0174] The first insulating member 28 is provided with a first insulator 283 of an annular structure and a second insulator 284 connected to the inner side of the first insulator 283. The second insulator 284 is configured to divide the internal space of the first insulator 283 into a first mounting hole 281 and a second mounting hole 282. The first insulator 283 and the second insulator 284 jointly define the first mounting hole 281 and the second mounting hole 282 for assembling the first and second current collecting members 25 and 27. The first insulating member 28 with such a structure can, on the one hand, surround the outside of the first and second current collecting members 25 and 27 through the first insulator 283, so that the first and second current collecting members 25 and 27 can be separated from the second wall 2152 of the housing 215, which helps to reduce the risk of short circuit between the first and second current collecting members 25 and 27. On the other hand, the second insulator 284 can separate the first and second current collecting members 25 and 27, which helps to reduce the risk of short circuit between the first and second current collecting members 25 and 27.

[0175] According to some embodiments of the present application, as shown in FIG. 4 , FIG. 6 and FIG. 7 , along the first direction X, a protrusion 271 is provided on one side of the second current collecting member 27 facing the first wall 2151 , and the protrusion 271 is connected to the first wall 2151 .

[0176] In which, the electrode terminal 216 protrudes from the side of the first wall 2151 facing the electrode assembly 23 along the first direction X, so that there is a distance between the surface of the first wall 2151 for connecting with the second current collecting member 27 and the end surface of the electrode terminal 216 for connecting with the first current collecting member 25 in the first direction X, thereby compensating for the distance difference between the first wall 2151 and the electrode terminal 216 by protruding a protrusion 271 on the side of the second current collecting member 27 facing the first wall 2151 and connecting the protrusion 271 to the first wall 2151.

[0177] By providing a protrusion 271 on the side of the second current collecting member 27 facing the first wall 2151, the second current collecting member 27 is connected to the first wall 2151 through the protrusion 271, which helps to reduce the assembly difficulty between the first wall 2151 and the second current collecting member 27 and improve the contact effect between the second current collecting member 27 and the first wall 2151.

[0178] It should be noted that, in other embodiments, the protrusion 271 may not be provided on the second current collecting member 27. The thickness of the second current collecting member 27 in the first direction X may be increased as a whole to compensate for the distance difference between the first wall 2151 and the electrode terminal 216. Alternatively, a connecting block may be provided on the side of the first wall 2151 facing the second current collecting member 27 to compensate for the distance difference between the first wall 2151 and the electrode terminal 216 through the connecting block. Alternatively, the first electrode tab 232 and the second electrode tab 233 may be provided with structures with different heights in the first direction X. That is, the dimension of the end of the first electrode tab 232 protruding from the main body 231 in the first direction X is smaller than the dimension of the end of the second electrode tab 233 protruding from the main body 231, so that the second electrode tab 233 is closer to the first wall 2151 than the first electrode tab 232 in the first direction X, so that the distance difference between the first wall 2151 and the electrode terminal 216 is compensated by the first electrode tab 232 and the second electrode tab 233 with different heights.

[0179] In some embodiments, along the first direction X, a groove 272 is formed on a side of the second current collecting member 27 away from the first wall 2151 and corresponding to the protrusion 271 .

[0180] Illustratively, the protrusion 271 provided on one side of the second current collecting member 27 is formed by a stamping process, whereby the protrusion 271 is formed on one side of the second current collecting member 27, and a groove 272 is formed on a side of the second current collecting member 27 opposite the protrusion 271 and corresponding to the protrusion 271. Of course, the processing method of the protrusion 271 provided on the side of the second current collecting member 27 is not limited to this. In other embodiments, the protrusion 271 provided on the side of the second current collecting member 27 may also be formed by a processing process such as laser etching, engraving, or casting.

[0181] It should be noted that, in other embodiments, the protrusion 271 and the second current collecting member 27 may also be separately arranged structures, that is, the protrusion 271 and the second current collecting member 27 are two independent components, and the protrusion 271 is connected to the surface of the second current collecting member 27 facing the first wall 2151 by welding or bonding.

[0182] By forming a groove 272 on the side of the second current collecting member 27 away from the protrusion 271 and in the area corresponding to the protrusion 271, the protrusion 271 of the second current collecting member 27 is made into a concave-convex structure that can be formed by stamping, so that the protrusion 271 and the groove 272 can be respectively formed on both sides of the second current collecting member 27. The current collecting member with such a structure is easy to manufacture and is conducive to reducing the processing difficulty of the protrusion 271, so as to improve the processing efficiency of setting the protrusion 271 on the second current collecting member 27.

[0183] According to some embodiments of the present application, as shown in Figures 6 and 7, along the first direction X, the first current collecting member 25 has a first surface 251 facing the first wall 2151, the electrode terminal 216 is connected to the first surface 251, and the second current collecting member 27 has a second surface 273 facing the first wall 2151, and the protrusion 271 is provided on the second surface 273. The first surface 251 and the second surface 273 are flush.

[0184] Among them, since the electrode terminal 216 protrudes from the side of the first wall 2151 facing the electrode assembly 23, and the first surface 251 of the first current collecting member 25 used to be connected to the electrode terminal 216 and the second surface 273 of the second current collecting member 27 facing the first wall 2151 are flush with each other, after the first surface 251 of the first current collecting member 25 is connected to the electrode terminal 216, there is a gap between the second surface 273 and the first wall 2151, so that by protruding a protrusion 271 on the second surface 273 and connecting it to the first wall 2151, the gap between the second surface 273 and the first wall 2151 can be effectively compensated.

[0185] Illustratively, a dimension of the protrusion 271 protruding from the second surface 273 in the first direction X is equal to a dimension of the electrode terminal 216 protruding from the side of the first wall 2151 facing the electrode assembly 23 .

[0186] Of course, in other embodiments, the battery cell 20 may have other structures, for example, the first surface 251 is closer to the first wall 2151 than the second surface 273 along the first direction X. In such an embodiment, the protrusion 271 protrudes from the second surface 273 in the first direction X by a distance equal to the distance between the second surface 273 and the first wall 2151.

[0187] By setting the first surface 251 of the first current collecting member 25 to be flush with the second surface 273 of the second current collecting member 27 or closer to the first wall 2151 than the second surface 273 of the second current collecting member 27, the protrusion 271 set on the second surface 273 of the second current collecting member 27 can compensate for the gap between the second surface 273 and the first wall 2151, so that the second current collecting member 27 can be connected to the first wall 2151 and the contact effect between the second current collecting member 27 and the first wall 2151 can be improved.

[0188] In some embodiments, referring to Figures 5 and 6, along the first direction X, the first electrode tab 232 has a third surface 2321 facing the first wall 2151, the first current collecting member 25 is connected to the third surface 2321, the second electrode tab 233 has a fourth surface 2331 facing the first wall 2151, the second current collecting member 27 is connected to the fourth surface 2331, and the third surface 2321 is flush with the fourth surface 2331.

[0189] The third surface 2321 of the first electrode tab 232 is flush with the fourth surface 2331 of the second electrode tab 233, so that the first electrode tab 232 and the second electrode tab 233 are protruding from the end of the main body 231 facing the first wall 2151 and are at the same height. In embodiments where the first surface 251 of the first current collecting member 25 and the second surface 273 of the second current collecting member 27 are flush with each other, the first and second current collecting members 25, 27 can have the same thickness, which helps optimize the internal space utilization of the battery cell 20.

[0190] By setting the third surface 2321 of the first electrode tab 232 facing the first wall 2151 and the fourth surface 2331 of the second electrode tab 233 facing the second wall 2152 to be flush with each other, on the one hand, it is convenient to process the first electrode tab 232 and the second electrode tab 233, and on the other hand, it can achieve the structure that the first current collecting member 25 and the second current collecting member 27 are flush with each other on the side facing the electrode assembly 23 in the first direction X, so as to reduce the position difference between the first current collecting member 25 and the second current collecting member 27 in the first direction X, thereby reducing the difficulty of assembling the first current collecting member 25 and the second current collecting member 27 between the electrode assembly 23 and the first wall 2151, and improving the internal space utilization of the battery cell 20.

[0191] According to some embodiments of the present application, as shown in FIG. 4 , the first wall 2151 and the second wall 2152 are separately provided, that is, the first wall 2151 and the second wall 2152 are a split structure.

[0192] The first wall 2151 and the second wall 2152 are provided separately, that is, the first wall 2151 and the second wall 2152 of the housing 215 are two independent components. Along the first direction X, the first wall 2151 is connected to the end of the second wall 2152 away from the opening 212. For example, the connection structure between the first wall 2151 and the second wall 2152 can be various, such as welding, bonding, or clamping.

[0193] By setting the first wall 2151 and the second wall 2152 as a separate structure, it is helpful to reduce the difficulty of assembling the electrode terminal 216 on the first wall 2151, and it is helpful to reduce the difficulty of assembling between the electrode terminal 216 and the first pole ear 232 and the difficulty of assembling between the first wall 2151 and the second pole ear 233, thereby reducing the manufacturing difficulty of the battery cell 20 and improving the production efficiency of the battery cell 20.

[0194] It should be noted that the structure of the battery cell 20 is not limited to this. In some embodiments, the battery cell 20 can also have other structures. For example, the first wall 2151 and the second wall 2152 are integrally formed. In other words, the first wall 2151 and the second wall 2152 are an integral structure, and the first wall 2151 and the second wall 2152 are made by an integral molding process such as stamping, casting or extrusion molding. By setting the first wall 2151 and the second wall 2152 as an integral structure, on the one hand, the connection stability and connection reliability between the first wall 2151 and the second wall 2152 can be improved, which is conducive to improving the overall structural strength of the shell 215. On the other hand, it can reduce the stress generated by the mutual assembly and connection of the first wall 2151 and the second wall 2152 on the electrode terminal 216 and other components.

[0195] According to some embodiments of the present application, as shown in FIG. 6 , along the first direction X, the thickness of the end cover 22 is D1 , satisfying 0.3 mm ≤ D1 ≤ 3.5 mm.

[0196] The end cover 22 is a circular plate-shaped structure, and the thickness direction of the end cover 22 is the same as the first direction X. The thickness D1 of the end cover 22 is the dimension of the end cover 22 in the first direction X.

[0197] Illustratively, the thickness D1 of the end cap 22 may be 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2 mm, 2.2 mm, 2.5 mm, 3 mm, or 3.5 mm, etc.

[0198] By setting the thickness of the end cap 22 in the first direction X to be greater than or equal to 0.3 mm, the end cap 22 has sufficient structural strength, which helps reduce the risk of deformation or damage to the end cap 22 during use or assembly. The end cap 22 also has sufficient space to dispose the pressure relief portion 221 on the end cap 22, which helps reduce the difficulty of disposing the pressure relief portion 221 on the end cap 22. In addition, by setting the thickness of the end cap 22 in the first direction X to be less than or equal to 3.5 mm, the space occupied by the end cap 22 in the first direction X is reduced, which helps improve the energy density of the battery cell 20.

[0199] According to some embodiments of the present application, as shown in FIG. 3 and FIG. 6 , the battery cell 20 is cylindrical, and the central axis of the battery cell 20 extends along the first direction X.

[0200] The battery cell 20 is cylindrical, and correspondingly, the shell 215 of the shell assembly 21 is cylindrical, and the end cover 22 is a circular plate-shaped structure.

[0201] By setting the battery cell 20 to be cylindrical, it is easy to process the battery cell 20 with a cylindrical structure, so that the battery cell 20 has the advantages of high capacity, long cycle life, and a wide range of operating ambient temperatures.

[0202] In some embodiments, as shown in FIG. 6 , the diameter of the battery cell 20 is D2 , which satisfies 27 mm ≤ D2 ≤ 100 mm.

[0203] For example, the diameter D2 of the battery cell 20 may be 27 mm, 30 mm, 32 mm, 35 mm, 38 mm, 40 mm, 42 mm, 45 mm, 48 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm or 100 mm, etc.

[0204] Preferably, the diameter of the battery cell 20 is D2, which satisfies 30 mm ≤ D2 ≤ 70 mm.

[0205] By setting the diameter of the battery cell 20 to be greater than or equal to 27 mm, sufficient space is provided inside the battery cell 20 to accommodate the electrode assembly 23, which helps reduce interference between the first electrode tab 232 and the second electrode tab 233 located at the same end of the main body 231 of the electrode assembly 23. In addition, by setting the diameter of the battery cell 20 to be less than or equal to 100 mm, the phenomenon of excessive number of electrode plate layers in the electrode assembly 23 due to the excessive internal space of the battery cell 20 is alleviated, which helps reduce the stress accumulation caused by the excessive number of electrode plate layers in the electrode assembly 23.

[0206] 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.

[0207] As shown in FIG. 2 , the battery 100 may further include a box body 10 , in which the battery cells 20 are accommodated.

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

[0209] 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.

[0210] 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.

[0211] 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.

[0212] The battery 100 may further include other structures. For example, the battery 100 may further include a busbar component that connects the plurality of battery cells 20 to achieve electrical connection between the plurality of battery cells 20 .

[0213] 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.

[0214] 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.

[0215] The electrical device may be any of the aforementioned devices or systems using the battery cell 20 .

[0216] According to some embodiments of the present application, referring to FIG. 3 to FIG. 8 , the present application provides a battery cell 20. The battery cell 20 is cylindrical and includes a housing assembly 21, an end cap 22, an electrode assembly 23, a first current collecting member 25, a second current collecting member 27, a first insulating member 28, and a second insulating member 24. The housing assembly 21 includes a housing 215 and an electrode terminal 216. The housing 215 is cylindrical and includes a first wall 2151 and a second wall 2152 that are separately provided. The second wall 2152 is provided around the first wall 2151. Along a first direction X, one end of the second wall 2152 is connected to the first wall 2151, and the other end encloses an opening 212. The first wall 2151 and the second wall 2152 together enclose a receiving cavity 211. The electrode terminal 216 is insulated and mounted on the first wall 2151. The first wall 215 1 is provided with an assembly hole 2151a, which passes through both sides of the first wall 2151 along the first direction X. The electrode terminal 216 is disposed within the assembly hole 2151a, and both ends of the electrode terminal 216 in the first direction X extend out of the assembly hole 2151a, so that both ends of the electrode terminal 216 in the first direction X protrude from both sides of the first wall 2151. The second insulating member 24 is disposed between the first wall 2151 and the electrode terminal 216 to insulate and isolate the first wall 2151 from the electrode terminal 216. The end cap 22 covers the opening 212 and is provided with a pressure relief portion 221. The pressure relief portion 221 is configured to release the internal pressure of the battery cell 20. The pressure relief portion 221 is integrally formed with the end cap 22. The electrode assembly 23 is housed within the accommodating cavity 211 and includes a main body 231, a first electrode tab 232, and a second electrode tab 233. The main body 231 is cylindrical. The first and second electrode tabs 232, 233 have opposite polarities and are located at one end of the main body 231 facing away from the end cap 22 in the first direction X. The first and second electrode tabs 232, 233 are electrically connected to the electrode terminal 216 and the first wall 2151, respectively. A first current collecting member 25 is disposed between the first wall 2151 and the electrode assembly 23, connecting the first electrode tab 232 and the electrode terminal 216. A through-hole 2311 is defined in the main body 231, extending through both ends of the main body 231 in the first direction X. The first current collecting member 25 is welded to the electrode terminal 216, forming a weld mark 26. At least a portion of the projection of the weld mark 26 in the first direction X is located within the through-hole 2311. The electrode assembly 23 is a wound electrode assembly 23 , and the through hole 2311 is the center hole of the main body 231 . The second current collecting member 27 is disposed between the first wall 2151 and the electrode assembly 23 , and connects the second electrode tab 233 and the first wall 2151 .Along the first direction X, the electrode terminal 216 protrudes from the side of the first wall 2151 facing the electrode assembly 23. The second current collecting member 27 has a protrusion 271 protruding from the side facing the first wall 2151. A groove 272 is formed on the side of the second current collecting member 27 facing away from the first wall 2151 and corresponding to the protrusion 271. The protrusion 271 is connected to the first wall 2151. Along the first direction X, the first current collecting member 25 has a first surface 251 facing the first wall 2151. The electrode terminal 216 is connected to the first surface 251. The second current collecting member 27 has a second surface 273 facing the first wall 2151. The protrusion 271 is provided on the second surface 273. The first surface 251 and the second surface 273 are flush. Along the first direction X, the first electrode tab 232 has a third surface 2321 facing the first wall 2151. The first current collecting member 25 is connected to the third surface 2321. The second electrode tab 233 has a fourth surface 2331 facing the first wall 2151. The second current collecting member 27 is connected to the fourth surface 2331. The third surface 2321 is flush with the fourth surface 2331. The first insulating member 28 is disposed between the electrode assembly 23 and the first wall 2151. The first current collecting member 25 and the second current collecting member 27 are spaced apart on the first insulating member 28. The first insulating member 28 includes a first insulator 283 and a second insulator 284. The first insulator 283 surrounds the first and second current collecting members 25 and 27. The second insulator 284 is connected to the inner circumference of the first insulator 283 and is located between the first and second current collecting members 25 and 27. The second insulator 284 and the first insulator 283 together define a first mounting hole 281 and a second mounting hole 282. The first current collecting member 25 is disposed in the first mounting hole 281, and the second current collecting member 27 is disposed in the second mounting hole 282. The thickness D1 of the end cap 22 along the first direction X satisfies the following conditions: 0.3 mm ≤ D1 ≤ 3.5 mm. The diameter D2 of the battery cell 20 satisfies the following conditions: 27 mm ≤ D2 ≤ 100 mm.

[0217] 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.

[0218] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those 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, comprising: A shell component, wherein a receiving cavity with an opening is formed inside, the shell component has a first electrode lead-out portion and a second electrode lead-out portion, along a first direction, the first electrode lead-out portion and the second electrode lead-out portion are both located at one end of the shell component away from the opening, the shell component comprises a shell and an electrode terminal, the shell comprises a first wall and a second wall, the second wall is arranged around the first wall, along the first direction, one end of the second wall is connected to the first wall, and the other end encloses the opening, the first wall and the second wall jointly enclose the receiving cavity, the electrode terminal is insulated and installed on the first wall, the electrode terminal is the first electrode lead-out portion, and the first wall is the second electrode lead-out portion; an end cover, covering the opening, the end cover being provided with a pressure relief portion, the pressure relief portion being configured to release the internal pressure of the battery cell; an electrode assembly, accommodated in the accommodation cavity, the electrode assembly comprising a main body, a first pole ear and a second pole ear, the first pole ear and the second pole ear having opposite polarities, the first pole ear and the second pole ear being arranged at an end of the main body away from the end cap in the first direction, the first pole ear and the second pole ear being electrically connected to the first electrode lead-out portion and the second electrode lead-out portion, respectively; as well as A first current collecting member, disposed between the first wall and the electrode assembly, the first current collecting member connecting the first electrode tab and the electrode terminal; The main body is provided with a through hole, which passes through both ends of the main body along the first direction, and the first current collecting member is welded to the electrode terminal to form a weld mark, and at least part of the projection of the weld mark is located in the through hole along the first direction.

2. The battery cell according to claim 1, wherein: The pressure relief portion and the end cover are integrally formed.

3. The battery cell according to claim 1, wherein: The pressure relief portion and the end cover are separately arranged.

4. The battery cell according to any one of claims 1 to 3, wherein: The electrode assembly is a wound electrode assembly, and the through hole is a central hole of the main body.

5. The battery cell according to any one of claims 1 to 4, wherein: The battery cell further comprises: The second current collecting member is disposed between the first wall and the electrode assembly, the second current collecting member is spaced apart from the first current collecting member, and the second current collecting member connects the second electrode tab and the first wall.

6. The battery cell according to claim 5, wherein: The battery cell further comprises: A first insulating member is disposed between the electrode assembly and the first wall, and the first insulating member insulates and isolates the first current collecting member from the second current collecting member.

7. The battery cell according to claim 6, wherein: The first insulating member is provided with a first mounting hole and a second mounting hole arranged at intervals, the first current collecting member is provided in the first mounting hole, and the second current collecting member is provided in the second mounting hole.

8. The battery cell according to claim 7, wherein: The first insulating member comprises: The first insulator is a ring-shaped structure; The second insulator is connected to the first insulator, the second insulator is configured to divide the inner space of the first insulator into the first mounting hole and the second mounting hole, and the second insulator is located between the first current collecting member and the second current collecting member.

9. The battery cell according to any one of claims 5 to 8, wherein: Along the first direction, a protrusion is provided on a side of the second current collecting member facing the first wall, and the protrusion is connected to the first wall.

10. The battery cell according to claim 9, wherein: Along the first direction, a groove is formed on a side of the second current collecting member away from the first wall and in an area corresponding to the protrusion.

11. The battery cell according to claim 9 or 10, wherein: Along the first direction, the first current collecting member has a first surface facing the first wall, the electrode terminal is connected to the first surface, and the second current collecting member has a second surface facing the first wall, the protrusion is provided on the second surface; wherein the first surface and the second surface are flush; or Along the first direction, the first surface is closer to the first wall than the second surface.

12. The battery cell according to claim 11, wherein: Along the first direction, the first electrode tab has a third surface facing the first wall, the first current collecting member is connected to the third surface, the second electrode tab has a fourth surface facing the first wall, the second current collecting member is connected to the fourth surface; Wherein, the third surface is flush with the fourth surface.

13. The battery cell according to any one of claims 1 to 12, wherein: The first wall and the second wall are arranged separately.

14. The battery cell according to any one of claims 1 to 12, wherein: The first wall and the second wall are integrally formed.

15. The battery cell according to any one of claims 1 to 14, wherein: Along the first direction, the thickness of the end cover is D1, satisfying 0.3 mm ≤ D1 ≤ 3.5 mm.

16. The battery cell according to any one of claims 1 to 15, wherein: The battery cell is cylindrical, and a central axis of the battery cell extends along the first direction.

17. The battery cell according to claim 16, wherein: The diameter of the battery cell is D2, which satisfies 27 mm ≤ D2 ≤ 100 mm.

18. A battery comprising the battery cell according to any one of claims 1 to 17.

19. An electrical device, comprising the battery cell according to any one of claims 1 to 17, wherein the battery cell is used to provide electrical energy.

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