Battery cell, battery, and electric device

Abstract

This application provides a battery cell, a battery, and an electrical device, belonging to the field of battery technology. The battery cell includes a casing, electrode terminals, and an electrode assembly. The casing has a wall portion. The electrode terminals are insulated and mounted on the wall portion. The electrode assembly is housed within the casing and includes a main body portion, a first electrode tab, and a second electrode tab. The first and second electrode tabs have opposite polarities. Along the thickness direction of the wall portion, both the first and second electrode tabs are located at the end of the main body portion facing the wall portion. The wall portion has a first surface facing the electrode assembly, and a connecting portion protrudes from the first surface. The connecting portion is electrically connected to the first electrode tab, and the electrode terminals are electrically connected to the second electrode tab. This battery cell optimizes the height of the first electrode tab protruding from the main body portion and improves the contact effect between the connecting portion and the first electrode tab. Furthermore, it eliminates the need for irregularly shaped components connecting the wall portion and the first electrode tab, thus reducing the assembly difficulty of the battery cell.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese patent application 2023111863066, 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] This application relates to the field of battery technology, and more specifically, to a battery cell, a battery, and an electrical device. Background Technology

[0004] In recent years, new energy vehicles have experienced rapid development. In the field of electric vehicles, power batteries, as the power source, play an irreplaceable and crucial role. With the vigorous promotion of new energy vehicles, the demand for power battery products is also increasing. As a core component of new energy vehicles, batteries have high requirements for reliability. A battery cell typically includes a casing and electrode components housed within the casing. However, the assembly process of existing battery cells is quite difficult, hindering the improvement of battery cell production efficiency. Summary of the Invention

[0005] This application provides a battery cell, a battery, and an electrical device, which can effectively improve the production efficiency of battery cells.

[0006] In a first aspect, embodiments of this application provide a battery cell, including a housing, electrode terminals, and an electrode assembly; the housing has a wall portion; the electrode terminals are insulatedly mounted on the wall portion; the electrode assembly is housed within the housing, the electrode assembly including a main body portion, a first electrode tab, and a second electrode tab, the first electrode tab and the second electrode tab having opposite polarities, and both the first electrode tab and the second electrode tab being disposed at one end of the main body portion facing the wall portion along the thickness direction of the wall portion; wherein, along the thickness direction of the wall portion, the wall portion has a first surface facing the electrode assembly and a second surface facing away from the first surface, and a connecting... The second surface of the battery cell has a groove formed on the position corresponding to the connecting portion. The connecting portion is electrically connected to the first electrode tab, and the electrode terminal is electrically connected to the second electrode tab. The battery cell also includes a first current collector, which is connected to the first electrode tab. The bottom wall of the groove is welded to the first current collector to electrically connect the first electrode tab and the wall portion, or the bottom wall of the groove is welded to the first electrode tab to electrically connect the first electrode tab and the wall portion. Along the thickness direction of the wall portion, the projected area of ​​the groove is S1, and the projected area of ​​the wall portion is S2, satisfying 0.1S2≤S1≤0.5S2.

[0007] In the above technical solution, by placing both the first and second tabs of the electrode assembly on the same end of the main body facing the wall in the thickness direction, it is beneficial to save space occupied by the electrode assembly and improve the energy density of the battery cell. Specifically, by providing a connecting portion protruding from the first surface of the wall, and having the connecting portion electrically connect with the first tab, it facilitates electrical connection between the wall and the first tab, optimizes the height of the first tab protruding from the main body, and improves the contact effect between the connecting portion and the first tab, thereby effectively improving the electrical connection between the wall and the first tab. Furthermore, it reduces the difficulty of electrical connection between the first tab and the wall, eliminating the need for irregularly shaped components connecting the wall and the first tab, thus reducing the assembly difficulty of the battery cell and effectively improving the production efficiency of the battery cell. Furthermore, by forming a groove on the second surface of the wall corresponding to the position of the connecting part, on the one hand, the connecting part of the wall can be formed into a concave-convex structure that can be formed by stamping, so that the connecting part and the groove are formed on both sides of the wall, which is convenient for manufacturing and helps to reduce the processing difficulty of the connecting part. On the other hand, the thickness of the connecting part can be reduced by the groove, thereby reducing the difficulty of electrical connection between the connecting part and the first electrode. At the same time, by setting the projected area of ​​the groove in the thickness direction of the wall to be greater than or equal to 0.1 times the projected area of ​​the wall in the thickness direction, the area of ​​the connecting part thinned by the groove is increased, thereby effectively increasing the welding connection area between the connecting part and the first current collector or the first electrode, which is beneficial to increasing the flow area between the connecting part and the first electrode. In addition, by setting the projected area of ​​the groove in the thickness direction of the wall to be less than or equal to 0.5 times the projected area of ​​the wall in the thickness direction of the wall, the phenomenon of the groove occupying too much space on the wall can be alleviated. On the one hand, this is conducive to improving the structural strength of the wall and reducing the risk of deformation or breakage during use. On the other hand, it can alleviate the phenomenon of excessive connecting parts protruding in the area corresponding to the groove on the first surface of the wall, which may cause interference between the connecting parts and other components inside the battery cell.

[0008] In some embodiments, the minimum width of the groove is W, which satisfies W≥5mm.

[0009] In the above technical solution, by setting the minimum width of the groove to be greater than or equal to 5mm, it is easier to weld the bottom wall of the groove to the first current collector or the first electrode ear. This helps to reduce the difficulty of welding the area of ​​the connection part thinned by the groove to the first current collector or the first electrode ear, thereby effectively alleviating the phenomenon that the bottom wall of the groove cannot be welded to the first current collector or the first electrode ear due to the small width of the groove.

[0010] In some embodiments, the groove is an arc-shaped groove extending along an arc trajectory.

[0011] In the above technical solution, by setting the groove as an arc-shaped groove structure extending along a circular arc trajectory, it is easier to process and manufacture, and the range of the area where the bottom wall of the groove is welded to the first current collector or the first electrode can be expanded, thereby effectively improving the electrical connection effect between the wall and the first electrode.

[0012] In some embodiments, the housing is cylindrical, the central axis of the housing extends along the thickness direction of the wall portion, and the central axis of the housing passes through the center of the circular arc trajectory of the groove.

[0013] In the above technical solution, by setting the outer shell as a cylindrical structure and the central axis of the outer shell extending along the thickness direction of the wall, the shape of the wall is circular. Thus, by setting the central axis of the outer shell as the center of the arc trajectory passing through the groove, the groove is an arc-shaped groove structure surrounding the central axis of the outer shell. On the one hand, this is beneficial to improve the space utilization of the groove on the wall, and on the other hand, it is easy to manufacture. It can also further expand the range of the area where the bottom wall of the groove is welded to the first current collector or the first electrode, so as to improve the electrical connection effect between the wall and the first electrode.

[0014] In some embodiments, along the thickness direction of the wall portion, the dimension of the connecting portion protruding from the first surface is D1, satisfying that D1≤8mm.

[0015] In the above technical solution, by setting the size of the connecting part protruding from the first surface to be less than or equal to 8mm, on the one hand, the phenomenon of excessive space occupied by the connecting part can be reduced, which is conducive to improving the internal space utilization of the battery cell. On the other hand, the interference effect caused by the connecting part on the electrical connection between the electrode terminal and the second tab can be reduced.

[0016] In some embodiments, a plurality of the connecting portions are protruding on the first surface.

[0017] In the above technical solution, by providing multiple connecting parts on the first surface of the wall, the wall can be electrically connected to the first electrode through the multiple connecting parts, which is beneficial to improving the effect of mutual electrical connection between the wall and the first electrode and can increase the current flow area between the wall and the first electrode.

[0018] In some embodiments, the wall portion is provided with an assembly hole that extends through the wall portion along its thickness direction, and the electrode terminal is disposed within the assembly hole and protrudes from the first surface.

[0019] In the above technical solution, by setting the electrode terminal to a structure that protrudes from the first surface in the thickness direction of the wall, it is easier for the electrode terminal to be electrically connected to the second electrode tab. This helps to reduce the difficulty of making an electrical connection between the electrode terminal and the second electrode tab. Furthermore, the connection portion protruding from the first surface of the wall can compensate for the height difference between the end face of the electrode terminal facing the electrode assembly and the first surface of the wall. Thus, while enabling the wall to be electrically connected to the first electrode tab, the electrical connection effect between the electrode terminal and the second electrode tab can be effectively improved.

[0020] In some embodiments, along the thickness direction of the wall portion, the dimension of the connecting portion protruding from the first surface is D1, and the dimension of the electrode terminal protruding from the first surface is D2, satisfying that D1 = D2.

[0021] In the above technical solution, by setting the size of the connecting part protruding from the first surface to be the same as the size of the electrode terminal protruding from the first surface, the end face of the connecting part facing the electrode assembly and the end face of the electrode terminal facing the electrode assembly are flush with each other in the thickness direction of the wall. On the one hand, it can reduce the difficulty of electrical connection between the connecting part and the first electrode tab and between the electrode terminal and the second electrode tab. On the other hand, it can reduce the phenomenon of poor electrical connection effect between the connecting part and the first electrode tab or between the electrode terminal and the second electrode tab due to mutual influence between the connecting part and the electrode terminal.

[0022] In some embodiments, the battery cell further includes a first current collector and a second current collector; the first current collector is located between the connecting portion and the first electrode tab, and the first current collector connects the connecting portion and the first electrode tab; the second current collector is located between the electrode terminal and the second electrode tab, and the second current collector is spaced apart from the first current collector, and the second current collector connects the electrode terminal and the second electrode tab.

[0023] In the above technical solution, by providing a first current collector between the connecting portion of the wall and the first electrode tab, and by connecting the connecting portion and the first electrode tab, an electrical connection between the first electrode tab and the wall is achieved, which helps to reduce the difficulty of electrically connecting the first electrode tab and the connecting portion. Similarly, by providing a second current collector between the electrode terminal and the second electrode tab, and by connecting the electrode terminal and the second electrode tab, an electrical connection between the second electrode tab and the electrode terminal is achieved, which helps to reduce the difficulty of electrically connecting the second electrode tab and the electrode terminal. In addition, by spacing the first current collector and the second current collector apart, the phenomenon of short circuit between the first current collector and the second current collector is reduced, which helps to reduce the usage risk of the battery cell.

[0024] In some embodiments, along the thickness direction of the wall portion, the first current collector has a third surface facing the wall portion, the third surface being connected to the connecting portion, and the second current collector has a fourth surface facing the wall portion, the fourth surface being connected to the electrode terminal; wherein the third surface and the fourth surface are flush.

[0025] In the above technical solution, by setting the third surface of the first current collector to be flush with the fourth surface of the second current collector, it is convenient to assemble the first current collector and the second current collector, which helps to reduce the difficulty of assembling the first current collector and the second current collector between the wall and the electrode assembly. On the other hand, the connecting part provided on the first surface of the wall can compensate for the gap between the first current collector and the wall, so as to realize that the first current collector can be electrically connected to the wall and improve the contact effect between the first current collector and the wall.

[0026] In some embodiments, along the thickness direction of the wall portion, the first electrode tab has a fifth surface facing the wall portion, the first current collector is connected to the fifth surface, the second electrode tab has a sixth surface facing the wall portion, and the second current collector is connected to the sixth surface; wherein, the fifth surface and the sixth surface are flush.

[0027] In the above technical solution, by setting the fifth surface of the first tab facing the wall and the sixth surface of the second tab facing the wall to be flush with each other, it is convenient to process the first tab and the second tab. On the other hand, it can realize that the first current collector and the second current collector are flush with each other on the side facing the electrode assembly in the thickness direction of the wall, so as to reduce the positional difference between the first current collector and the second current collector in the thickness direction of the wall. This helps to reduce the difficulty of assembling the first current collector and the second current collector between the electrode assembly and the wall, and also helps to improve the internal space utilization of the battery cell.

[0028] In some embodiments, the battery cell further includes a first insulating member; the first insulating member is disposed between the electrode assembly and the wall portion, and the first insulating member insulatingly isolates the first current collector and the second current collector.

[0029] In the above technical solution, by providing a first insulating member between the electrode assembly and the wall, and the first insulating member being used to insulate and isolate the first current collector and the second current collector, insulation and isolation between the first current collector and the second current collector can be achieved, which helps to further reduce the risk of short circuit between the first current collector and the second current collector.

[0030] 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 collector is disposed in the first mounting hole, and the second current collector is disposed in the second mounting hole.

[0031] In the above technical solution, by providing a first mounting hole and a second mounting hole arranged at intervals on the first insulating member, and the first current collector and the second current collector being respectively disposed in the first mounting hole and the second mounting hole, on the one hand, it is possible to assemble the first current collector and the second current collector onto the first insulating member, so that the first insulating member can play a supporting and assembling role for the first current collector and the second current collector, which helps to reduce the difficulty of setting the first current collector and the second current collector between the wall and the electrode assembly. On the other hand, it is possible to achieve the first current collector and the second current collector being disposed at intervals on the first insulating member, so as to achieve insulation isolation between the first current collector and the second current collector.

[0032] In some embodiments, the first insulating member includes a first insulator and a second insulator; the first insulator is an annular structure; the second insulator is connected to 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, and the second insulator is located between the first current collector and the second current collector.

[0033] In the above technical solution, the first insulating member is provided with a first insulator with an annular structure and a second insulator connected to the inner side of the first insulator. 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 together define the first mounting hole and the second mounting hole for assembling the first current collector and the second current collector. The first insulating member with this structure can, on the one hand, surround the outside of the first current collector and the second current collector by the first insulator, so that the first current collector and the second current collector can be separated from the housing, which helps to reduce the risk of short circuit between the first current collector and the second current collector and the housing. On the other hand, the second insulator can separate the first current collector and the second current collector, which helps to reduce the risk of short circuit between the first current collector and the second current collector.

[0034] In some embodiments, the housing is cylindrical, and the central axis of the housing extends along the thickness direction of the wall portion.

[0035] In the above technical solution, by setting the outer shell to a cylindrical shape, it is easier to process and form a cylindrical battery cell, which gives the battery cell advantages such as high capacity, long cycle life and wide operating temperature range.

[0036] In some embodiments, the housing includes a housing and an end cap; the housing includes a sidewall and the wall portion, the sidewall surrounding the wall portion, one end of the sidewall being connected to the wall portion along the thickness direction of the wall portion, and the other end forming an opening, the sidewall and the wall portion together defining a receiving cavity for accommodating the electrode assembly; the end cap closes the opening.

[0037] In the above technical solution, by setting the wall of the outer casing as the bottom wall opposite to the end cap, the wall where the electrode terminals are located and for electrical connection with the first electrode tab can be moved away from the end cap. This reduces the impact of stress generated when the end cap and the casing are connected to each other on the wall or the electrode terminals located on the wall, which is beneficial to improving the reliability and service life of the battery cell.

[0038] In some embodiments, the housing includes a shell and an end cap; the interior of the shell forms a receiving cavity with an opening for receiving the electrode assembly; the end cap closes the opening; wherein the end cap is the wall portion.

[0039] In the above technical solution, by setting the wall of the outer casing as an end cap for closing the opening of the casing, the battery cell with this structure is easy to assemble electrode terminals on the end cap, and can reduce the difficulty of electrically connecting the first tab and the second tab to the end cap and the electrode terminals respectively, thereby helping to reduce the manufacturing difficulty of the battery cell and improve the production efficiency of the battery cell.

[0040] Secondly, embodiments of this application also provide a battery, including the aforementioned battery cell.

[0041] Thirdly, embodiments of this application also provide an electrical device, including the aforementioned battery cell, wherein the battery cell is used to provide electrical energy. Attached Figure Description

[0042] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This application provides structural schematic diagrams of vehicles for some embodiments;

[0044] Figure 2 Exploded views of the battery structure provided in some embodiments of this application;

[0045] Figure 3This is a schematic diagram of the structure of a battery cell provided in some embodiments of this application;

[0046] Figure 4 Exploded views of the structure of a single battery cell provided in some embodiments of this application;

[0047] Figure 5 Partial cross-sectional view of a battery cell provided in some embodiments of this application;

[0048] Figure 6 for Figure 5 A magnified view of part A of the shown battery cell;

[0049] Figure 7 A top view of a battery cell provided in some embodiments of this application;

[0050] Figure 8 A top view of a battery cell provided for some embodiments of this application;

[0051] Figure 9 A schematic diagram showing the connection of the first current collector and the second current collector of a battery cell assembled on a first insulating member, as provided in some embodiments of this application;

[0052] Figure 10 This is a schematic diagram of the structure of the first insulating element of a battery cell provided in some embodiments of this application.

[0053] Icons: 1000 - Vehicle; 100 - Battery; 10 - Housing; 11 - First Housing Body; 12 - Second Housing Body; 20 - Battery Cell; 21 - Housing; 211 - Wall; 2111 - First Surface; 2112 - Connecting Part; 2113 - Mounting Hole; 2114 - Second Surface; 2115 - Groove; 212 - Housing; 2121 - Opening; 2122 - Side Wall; 2123 - Bottom Wall; 213 - End Cap; 22 - Electrode Terminal; 23 - Electrode Assembly; 231 - Main Body Part; 232-First tab; 2321-Fifth surface; 233-Second tab; 2331-Sixth surface; 24-Second insulator; 25-First current collector; 251-Third surface; 26-Second current collector; 261-Fourth surface; 27-Pressure relief component; 28-First insulator; 281-First mounting hole; 282-Second mounting hole; 283-First insulator; 284-Second insulator; 200-Controller; 300-Motor; X-Thickness direction of the wall part. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0055] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

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

[0057] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0058] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

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

[0060] In this application, "multiple" means two or more (including two).

[0061] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0062] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0063] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0064] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

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

[0066] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, it can be 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. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0067] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide 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, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al 0.05 At least one of O2 and its modified compounds.

[0068] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, lithium source material, potassium metal, or sodium metal may also be filled and / or deposited within the foamed metal, where the lithium source material is lithium metal and / or a lithium-rich material.

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

[0070] As an example, the negative electrode current collector can be a metal foil, a foamed metal, or a composite current collector. For example, as a metal foil, it can be silver-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium, etc. Foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors 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.).

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

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

[0073] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0074] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0075] In some embodiments, the electrode assembly further includes an isolator disposed between the positive and negative electrodes.

[0076] In some embodiments, the separator is a separator membrane. The separator membrane can be of various types, and any known porous separator membrane with good chemical and mechanical stability can be selected.

[0077] As an example, the material of the separator may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or it may be attached to the surfaces of the positive and negative electrodes.

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

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

[0080] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0081] In some embodiments, the solvent may include at least one selected from ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more selected from ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

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

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

[0084] As an example, polymer solid electrolytes can be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0085] As an example, inorganic solid electrolytes may include one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphate sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0086] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0087] In some implementations, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0088] In some implementations, the electrode assembly may be cylindrical in shape.

[0089] In some embodiments, the electrode assembly is provided with tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0090] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing may be made of steel, aluminum, plastic (such as polypropylene), composite metal (such as copper-aluminum composite), or aluminum-plastic film, etc.

[0091] As an example, a battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes.

[0092] The battery mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity.

[0093] In some embodiments, the battery can be a battery module, and when there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0094] In some embodiments, the battery can be a battery pack, which includes a housing and individual battery cells, with the individual battery cells or battery modules housed within the housing.

[0095] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0096] In some embodiments, the battery can be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0097] Batteries possess outstanding advantages such as high energy density, low environmental pollution, high power density, long lifespan, wide applicability, and low self-discharge coefficient, making them a crucial component of today's new energy development. The development of battery technology must simultaneously consider multiple design factors, such as performance parameters like energy density, cycle life, discharge capacity, and charge / discharge rate. Furthermore, battery safety and production efficiency must also be taken into account.

[0098] For a typical battery cell, it usually includes a casing and an electrode assembly housed within the casing. The casing includes an end cap and an integrally formed housing. The end cap covers one end of the housing. The electrode assembly typically has a main body and positive and negative tabs. The positive and negative tabs are used to output or input electrical energy to the electrode assembly. In order to save the space occupied by the electrode assembly within the casing and improve the energy density of the battery cell, especially in cylindrical battery cells, in related technologies, the positive and negative tabs of the electrode assembly are usually located at the same end of the main body, and the electrode terminals are insulated and installed on the end cap. At the same time, two current collectors are provided within the casing. One current collector connects the end cap and one tab of the electrode assembly, and the other current collector connects the electrode terminal and the other tab of the electrode assembly, so that the positive and negative terminals of the battery cell are output or input through the end cap and the electrode terminal respectively. This achieves a structure where the electrode assembly has tabs on the same side, thereby saving the space occupied by the electrode assembly within the casing. However, in this type of battery cell, since the electrode terminals protrude from the side of the end cap facing the electrode assembly, in order to compensate for the height difference between the side of the end cap facing the electrode assembly and the electrode terminals, the current collector of the tab connecting the end cap and the electrode assembly is usually set as an irregular structure, such as a "Z" shape, so that the tab can be welded to the end cap through the current collector. However, it is difficult to assemble the current collector of this structure into the housing, and a support needs to be set below the current collector to ensure that the current collector can contact the end cap for easy welding. The structure is relatively complex and not easy to assemble, which makes the battery cell more difficult to assemble and is not conducive to improving the production efficiency of the battery cell.

[0099] Based on the above considerations, in order to solve the problem of the high difficulty in assembling battery cells, this application provides a battery cell including a casing, electrode terminals, and an electrode assembly. The casing has a wall portion, and the electrode terminals are insulated and mounted on the wall portion. The electrode assembly is housed within the casing and includes a main body portion, a first electrode tab, and a second electrode tab. The first and second electrode tabs have opposite polarities, and along the thickness direction of the wall portion, both the first and second electrode tabs are disposed at the end of the main body portion facing the wall portion. Along the thickness direction of the wall portion, the wall portion has a first surface facing the electrode assembly, and a connecting portion is protruding on the first surface. The connecting portion is electrically connected to the first electrode tab, and the electrode terminals are electrically connected to the second electrode tab.

[0100] In this type of battery cell structure, by placing both the first and second tabs of the electrode assembly on the same end of the main body facing the wall in the thickness direction, it is beneficial to save space occupied by the electrode assembly and thus improve the energy density of the battery cell. Furthermore, by providing a connecting portion protruding from the first surface of the wall, which is used for electrical connection with the first tab, it facilitates electrical connection between the wall and the first tab, optimizes the height of the first tab protruding from the main body, and improves the contact effect between the connecting portion and the first tab, thereby effectively improving the electrical connection between the wall and the first tab. On the other hand, it reduces the difficulty of electrical connection between the first tab and the wall, eliminating the need for irregularly shaped components connecting the wall and the first tab, thus reducing the assembly difficulty of the battery cell and effectively improving the production efficiency of the battery cell.

[0101] The battery cells disclosed in this application can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. A power system for such an electrical device can be constructed using battery cells and batteries disclosed in this application. This helps alleviate the excessive difficulty in assembling battery cells and improves the production efficiency of battery cells.

[0102] This application provides an electrical device that uses a battery as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0103] For ease of explanation, the following embodiments will be described using a vehicle as an example of an electrical device according to an embodiment of this application.

[0104] Please refer to Figure 1 , Figure 1This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery 100 is disposed inside the vehicle 1000. The battery 100 can be disposed at the bottom, front, or rear of the vehicle 1000. The battery 100 can be used to power the vehicle 1000; for example, the battery 100 can serve as the operating power source or general power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 controls the battery 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during startup, navigation, and driving.

[0105] In some embodiments of this application, the battery 100 can not only serve as the operating power or power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0106] Please refer to Figure 2 and Figure 3 , Figure 2 This is an exploded view of the structure of the battery 100 provided in some embodiments of this application. Figure 3 This is a schematic diagram of the structure of a battery cell 20 provided in some embodiments of this application. The battery 100 includes a housing 10 and a battery cell 20, which is housed within the housing 10.

[0107] The housing 10 provides assembly space for the battery cell 20, and can adopt various structures. In some embodiments, the housing 10 may include a first housing body 11 and a second housing body 12, which overlap each other, and together define an assembly space for accommodating the battery cell 20. The second housing body 12 may be a hollow structure open at one end, and the first housing body 11 may be a plate-like structure, with the first housing body 11 covering the open side of the second housing body 12 so that the first housing body 11 and the second housing body 12 together define the assembly space; alternatively, the first housing body 11 and the second housing body 12 may both be hollow structures open on one side, with the open side of the first housing body 11 covering the open side of the second housing body 12.

[0108] Of course, the box 10 formed by the first box body 11 and the second box body 12 can be of various shapes, such as a cylinder, a cuboid, or a cube. For example, in... Figure 2 In the middle, the shape of box 10 is a cuboid.

[0109] In battery 100, there can be one or more battery cells 20 disposed within housing 10. When there are multiple battery cells 20 disposed within housing 10, they can be connected in series, in parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 20 are connected in both series and parallel configurations. Multiple battery cells 20 can be directly connected in series, in parallel, or in a mixed configuration, and then the entire assembly of multiple battery cells 20 is housed within housing 10. Alternatively, battery 100 can also be composed of multiple battery cells 20 first connected in series, in parallel, or in a mixed configuration to form a battery module, and then multiple battery modules are connected in series, in parallel, or in a mixed configuration to form a whole, which is then housed within housing 10.

[0110] In some embodiments, the battery 100 may also include other structures. For example, the battery 100 may also include a busbar for connecting 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 is not limited to these. The battery cell 20 can be cylindrical, prismatic, or other shapes. For example, in... Figure 3 In the middle, the battery cell 20 has a cylindrical structure.

[0112] According to some embodiments of this application, refer to Figure 3 Please refer to further details. Figure 4 , Figure 5 and Figure 6 , Figure 4 This is an exploded view of the structure of a battery cell 20 provided in some embodiments of this application. Figure 5 This is a partial cross-sectional view of a battery cell 20 provided in some embodiments of this application. Figure 6 for Figure 5 The image shows a partial enlarged view of point A of the battery cell 20. This application provides a battery cell 20, which includes a housing 21, electrode terminals 22, and an electrode assembly 23. The housing 21 has a wall portion 211, and the electrode terminals 22 are insulatedly mounted on the wall portion 211. The electrode assembly 23 is housed within the housing 21 and includes a main body portion 231, a first tab 232, and a second tab 233. The first tab 232 and the second tab 233 have opposite polarities. Along the thickness direction X of the wall portion, both the first tab 232 and the second tab 233 are disposed at the end of the main body portion 231 facing the wall portion 211. Along the thickness direction X of the wall portion, the wall portion 211 has a first surface 2111 facing the electrode assembly 23. A connecting portion 2112 protrudes from the first surface 2111, which is electrically connected to the first tab 232, and the electrode terminals 22 are electrically connected to the second tab 233.

[0113] The outer shell 21 can also be used to contain electrolytes, such as electrolyte solutions. The outer shell 21 can also be made of various materials, such as copper, iron, aluminum, steel, or aluminum alloys.

[0114] In some embodiments, the housing 21 may include a housing 212 and an end cap 213. The housing 212 has an internal cavity for accommodating the electrode assembly 23 and has an opening 2121. That is, the housing 212 is a hollow structure with an opening 2121 at one end. The end cap 213 covers the opening 2121 of the housing 212 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 23 and the electrolyte.

[0115] When assembling the battery cell 20, the electrode assembly 23 can be placed into the housing 212 first, and the electrolyte can be filled into the housing 212. Then, the end cap 213 can be closed onto the opening 2121 of the housing 212 to complete the assembly of the battery cell 20.

[0116] The housing 212 can have various shapes, such as a cylindrical or prismatic structure. The shape of the housing 212 can be determined according to the specific shape of the electrode assembly 23. For example, if the electrode assembly 23 is a cylindrical structure, then a cylindrical housing 212 can be selected. Of course, the structure of the end cap 213 can also be various, such as a plate-like structure or a hollow structure open at one end. For example, in Figure 4 In the middle, the shell 212 is a cylindrical structure, the central axis of the shell 212 extends along the thickness direction X of the wall, and the end cap 213 is a plate-like structure.

[0117] It should be noted that the wall portion 211 for mounting the electrode terminal 22 and providing the connecting portion 2112 can be the end cap 213 of the housing 21, or it can be a wall of the housing 212. For example, in... Figure 3 and Figure 4 In this embodiment, the housing 212 may include a side wall 2122 and a bottom wall 2123. The side wall 2122 surrounds the bottom wall 2123. Along the thickness direction X of the wall portion, the bottom wall 2123 is disposed opposite to the end cap 213. One end of the side wall 2122 is connected to the bottom wall 2123, and the other end forms an opening 2121. The bottom wall 2123 is a wall portion 211 for mounting electrode terminals 22 and having a connecting portion 2112. Of course, the structure of the battery cell 20 is not limited to this. In other embodiments, the wall portion 211 may also be the end cap 213 of the housing 21.

[0118] Optionally, the sidewalls 2122 and bottomwalls 2123 of the housing 212 can be integrally formed, for example, by stamping or casting. Of course, the sidewalls 2122 and bottomwalls 2123 of the housing 212 can also be separate structures, that is, the sidewalls 2122 and bottomwalls 2123 are separately set, and the bottomwalls 2123 can be connected to the sidewalls 2122 by welding or bonding.

[0119] For example, in Figure 4 In the middle, the side wall 2122 and the bottom wall 2123 are integrally formed structures.

[0120] It should be noted that in embodiments where the side wall 2122 and bottom wall 2123 are separate components, the end cap 213 and side wall 2122 can be integrally formed or separate components. For example, in... Figure 4 In the middle, the end cap 213 and the side wall 2122 are separate structures. The end cap 213 is welded to the end of the side wall 2122 away from the bottom wall 2123 in the thickness direction X of the wall.

[0121] Electrode assembly 23 is a component in the battery cell 20 where electrochemical reactions occur. The structure of electrode assembly 23 can be varied; exemplarily, in... Figure 4 In the process, the electrode assembly 23 is a wound structure formed by winding a positive electrode sheet, an insulating element and a negative electrode sheet, and the main body 231 of the electrode assembly 23 is cylindrical, with the central axis of the main body 231 extending along the thickness direction X of the wall.

[0122] For example, the separator is a separator membrane, and the main material of the separator membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride.

[0123] The main body 231 is the area where the electrode assembly 23 undergoes a chemical reaction within the battery cell 20. The main body 231 is a structure formed by winding the area where the positive electrode sheet is coated with a positive active material layer, the separator, and the area where the negative electrode sheet is coated with a negative active material layer. It mainly relies on the movement of metal ions between the positive and negative electrode sheets with opposite polarities to work.

[0124] The first electrode 232 and the second electrode 233 are both disposed at the end of the main body 231 facing the wall 211 in the thickness direction X of the wall portion. That is, the first electrode 232 and the second electrode 233 are disposed at the same end of the main body 231 in the thickness direction X of the wall portion, and are located at the end of the main body 231 facing the wall 211 in the thickness direction X of the wall portion.

[0125] The first tab 232 and the second tab 233 are used as the positive and negative electrodes of the output or input electrode assembly 23, respectively. If the first tab 232 is used as the positive electrode of the input or output electrode assembly 23, then the first tab 232 is a component formed by stacking and connecting the regions of the positive electrode sheet that are not coated with a positive active material layer. Correspondingly, if the second tab 233 is used as the negative electrode of the output or input electrode assembly 23, then the second tab 233 is a component formed by stacking and connecting the regions of the negative electrode sheet that are not coated with a negative active material layer. If the first tab 232 is used as the negative electrode of the output or input electrode assembly 23, then the first tab 232 is a component formed by stacking and connecting the regions of the negative electrode sheet that are not coated with a negative active material layer. Correspondingly, if the second tab 233 is used as the positive electrode of the input or output electrode assembly 23, then the second tab 233 is a component formed by stacking and connecting the regions of the positive electrode sheet that are not coated with a positive active material layer. For example, in the embodiments of this application, the first tab 232 is used as the negative electrode of the output or input electrode assembly 23, and the second tab 233 is used as the positive electrode of the output or input electrode assembly 23.

[0126] The electrode terminal 22 serves to output or input electrical energy to the battery cell 20, and its material can be various, such as copper, iron, aluminum, steel or aluminum alloy.

[0127] The electrode terminal 22 is insulated from the wall portion 211, meaning no electrical connection is formed between the electrode terminal 22 and the wall portion 211. See also, in some embodiments, for details. Figure 5 and Figure 6 As shown, the wall portion 211 is provided with a mounting hole 2113, which extends through both sides of the wall portion 211 along the thickness direction X. The electrode terminal 22 passes through the mounting hole 2113, and both ends of the electrode terminal 22 in the thickness direction X of the wall portion extend out of the mounting hole 2113, so that both ends of the electrode terminal 22 in the thickness direction X of the wall portion protrude from both sides of the wall portion 211, so that one end of the electrode terminal 22 facing the electrode assembly 23 in the thickness direction X of the wall portion can be electrically connected to the second tab 233, and the other end can be electrically connected to the current collector of the battery 100.

[0128] The battery cell 20 may also include a second insulating member 24, which is disposed between the wall portion 211 and the electrode terminal 22 to insulate and isolate the wall portion 211 and the electrode terminal 22, thereby achieving the insulated mounting of the electrode terminal 22 on the wall portion 211.

[0129] For example, the material of the second insulating element 24 may be rubber, plastic or silicone, etc.

[0130] exist Figure 6Along the thickness direction X of the wall portion, the wall portion 211 has a first surface 2111 facing the electrode assembly 23, and the electrode terminal 22 protrudes from the first surface 2111. That is, in the thickness direction X of the wall portion, the end of the electrode terminal 22 near the electrode assembly 23 extends out of the surface of the wall portion 211 facing the electrode assembly 23, so that the end face of the electrode terminal 22 facing the electrode assembly 23 is closer to the main body portion 231 of the electrode assembly 23 than the first surface 2111.

[0131] A connecting portion 2112 is provided on the first surface 2111. That is, the connecting portion 2112 is a structure that protrudes from the side of the wall portion 211 facing the electrode assembly 23, and the connecting portion 2112 is connected to the first surface 2111.

[0132] It should be noted that the connection between the connecting part 2112 and the first electrode 232 can be achieved by direct connection, such as welding or abutment, or by connecting the connecting part 2112 to other components before connecting to the first electrode 232. Similarly, the connection between the electrode terminal 22 and the second electrode 233 can be achieved by direct connection, such as welding or abutment, or by connecting the electrode terminal 22 to other components before connecting to the second electrode 233.

[0133] For example, in Figure 4 and Figure 5 In the battery cell 20, a first current collector 25 and a second current collector 26 may also be included. Both the first current collector 25 and the second current collector 26 are disposed between the electrode assembly 23 and the wall portion 211. Along the thickness direction X of the wall portion, the two sides of the first current collector 25 are respectively connected to the connecting portion 2112 and the first electrode tab 232 to realize the electrical connection between the connecting portion 2112 and the first electrode tab 232. The connection structure between the first current collector 25 and the connecting portion 2112 and between the first current collector 25 and the first electrode tab 232 can be welding or abutting, etc. Similarly, along the thickness direction X of the wall portion, the two sides of the second current collector 26 are respectively connected to the electrode terminal 22 and the second electrode tab 233 to realize the electrical connection between the electrode terminal 22 and the second electrode tab 233. The connection structure between the second current collector 26 and the electrode terminal 22 and between the second current collector 26 and the second electrode tab 233 can be welding or abutting, etc.

[0134] In some embodiments, see Figure 4As shown, the battery cell 20 may further include a pressure relief component 27, which is disposed on the housing 21. The pressure relief component 27 is used to release the internal pressure of the battery cell 20 when the internal pressure or temperature of the battery cell 20 reaches a predetermined value. Optionally, the pressure relief component 27 may be disposed on the end cap 213 of the housing 21 or on the housing 212 of the housing 21.

[0135] For example, in Figure 4 In this configuration, the pressure relief component 27 is mounted on the end cap 213. Similarly, the pressure relief component 27 and the outer casing 21 can be integrally formed or separately configured. For example, in... Figure 4 In this embodiment, the pressure relief component 27 and the end cap 213 of the outer casing 21 are integrally formed. The pressure relief component 27 is the area on the end cap 213 where a weak structure is formed, such as the area on the end cap 213 where a groove is provided. Of course, in other embodiments, the pressure relief component 27 and the end cap 213 can also be separate structures. The pressure relief component 27 can be connected to the end cap 213 by welding or other means. Correspondingly, the pressure relief component 27 can be a component such as an explosion-proof valve, an explosion-proof disc, a gas valve, a pressure relief valve, or a safety valve.

[0136] By placing both the first tab 232 and the second tab 233 of the electrode assembly 23 on the same end of the main body 231 facing the wall 211 in the thickness direction X of the wall, it is beneficial to save the space occupied by the electrode assembly 23 and improve the energy density of the battery cell 20. By providing a connecting portion 2112 protruding from the first surface 2111 of the wall portion 211, and using the connecting portion 2112 for electrical connection with the first tab 232, it is convenient for the wall portion 211 to be electrically connected to the first tab 232 through the connecting portion 2112. This helps to optimize the height of the first tab 232 protruding from the main body portion 231 and improves the contact effect between the connecting portion 2112 and the first tab 232, thereby effectively improving the electrical connection effect between the wall portion 211 and the first tab 232. On the other hand, it reduces the difficulty of electrical connection between the first tab 232 and the wall portion 211, eliminating the need to set up irregularly shaped components connecting the wall portion 211 and the first tab 232, thereby reducing the assembly difficulty of the battery cell 20 and effectively improving the production efficiency of the battery cell 20.

[0137] According to some embodiments of this application, see Figure 4 , Figure 5 and Figure 6 As shown, along the thickness direction X of the wall portion, the wall portion 211 has a second surface 2114 that is away from the first surface 2111, and a groove 2115 is formed on the second surface 2114 at the position corresponding to the connecting portion 2112.

[0138] The groove 2115 on the second surface 2114 of the wall portion 211 is formed by a stamping process to form a connecting portion 2112 on the first surface 2111 of the wall portion 211. The groove 2115 is formed on the second surface 2114 of the wall portion 211 away from the first surface 2111 and at a position corresponding to the connecting portion 2112. Of course, the processing method of the connecting portion 2112 protruding from the first surface 2111 of the wall portion 211 is not limited to this. In other embodiments, the connecting portion 2112 protruding from the first surface 2111 of the wall portion 211 can also be formed by casting or other processes, or the connecting portion 2112 can be connected to the first surface 2111 of the wall portion 211 by welding or bonding or other connection structures.

[0139] For example, along the thickness direction X of the wall portion, the groove depth of the groove 2115 is equal to the size of the connecting portion 2112 protruding from the first surface 2111, so that the thickness of the bottom wall 2123 of the groove 2115 can be equal to the thickness of the wall portion 211.

[0140] A groove 2115 is formed on the second surface 2114 of the wall portion 211 corresponding to the position of the connecting portion 2112. On the one hand, this makes the connecting portion 2112 of the wall portion 211 a concave-convex structure that can be formed by stamping, so that the connecting portion 2112 and the groove 2115 are formed on both sides of the wall portion 211 respectively, which is convenient for manufacturing and helps to reduce the processing difficulty of the connecting portion 2112. On the other hand, the thickness of the connecting portion 2112 can be reduced by the groove 2115, thereby reducing the difficulty of electrical connection between the connecting portion 2112 and the first electrode 232.

[0141] According to some embodiments of this application, please continue to refer to Figure 4 , Figure 5 and Figure 6 As shown, the battery cell 20 may also include a first current collector 25, which is connected to the first tab 232. The bottom wall 2123 of the groove 2115 is welded to the first current collector 25 to electrically connect the first tab 232 and the wall 211.

[0142] Along the thickness direction X of the wall portion, the first current collector 25 is disposed between the connecting portion 2112 and the first electrode tab 232 of the electrode assembly 23. The first current collector 25 serves to connect the first electrode tab 232 and the connecting portion 2112. The material of the first current collector 25 can be various, such as copper, iron, aluminum, steel or aluminum alloy.

[0143] The first current collector 25 is connected to the first electrode 232. That is, the side of the first current collector 25 facing the first electrode 232 is connected to the first electrode 232 so that the first current collector 25 and the first electrode 232 are electrically connected. The connection structure between the first current collector 25 and the first electrode 232 can be various, such as welding or abutting.

[0144] The bottom wall 2123 of the groove 2115 is welded to the first current collector 25, that is, the area of ​​the connecting part 2112 corresponding to the groove 2115 is welded to the first current collector 25 so that the wall part 211 can be electrically connected to the first current collector 25 through the connecting part 2112. In other words, the area of ​​the connecting part 2112 that is thinned by the groove 2115 is welded to the first current collector 25.

[0145] It should be noted that in some embodiments, the battery cell 20 may not be provided with the first current collector 25. For example, the bottom wall 2123 of the groove 2115 is welded to the first tab 232 to electrically connect the first tab 232 and the wall portion 211. That is, the area of ​​the connecting portion 2112 that is thinned by the groove 2115 is directly welded to the first tab 232 so that the wall portion 211 can be electrically connected to the first tab 232 through the connecting portion 2112.

[0146] By providing a first current collector 25 between the connecting part 2112 and the first tab 232, and connecting the first current collector 25 to the first tab 232, the bottom wall 2123 of the groove 2115 and the first current collector 25 are welded together, which enables the electrical connection between the first tab 232 and the wall 211. The battery cell 20 with this structure can improve the connection reliability between the connecting part 2112 and the first current collector 25, thereby improving the stability of the electrical connection between the wall 211 and the first tab 232. On the other hand, by welding the bottom wall 2123 of the groove 2115 to the first current collector 25, the connecting part 2112 is the area thinned by the groove 2115 and is welded to the first current collector 25, which helps to reduce the difficulty of welding the connecting part 2112 and the first current collector 25 together. Similarly, by directly welding the bottom wall 2123 of the groove 2115 to the first tab 232, an electrical connection between the wall 211 and the first tab 232 is achieved. The battery cell 20 with this structure can improve the connection reliability between the connecting part 2112 and the first tab 232, thereby enhancing the stability of the electrical connection between the wall 211 and the first tab 232. On the other hand, by welding the bottom wall 2123 of the groove 2115 to the first tab 232, the connecting part 2112 is a region thinned by the groove 2115 that is welded to the first tab 232, which helps to reduce the difficulty of welding the connecting part 2112 and the first tab 232 to each other.

[0147] According to some embodiments of this application, see Figure 4 and Figure 6 As shown, the minimum width of groove 2115 is W, which satisfies W≥5mm.

[0148] Among them, Figure 4 In the middle, the groove 2115 is an arc-shaped groove structure, and the minimum width W of the groove 2115 is the minimum width of the cross section of the groove 2115 in its extension direction.

[0149] For example, the minimum width W of the groove 2115 can be 5mm, 5.5mm, 5.8mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm or 10mm, etc.

[0150] By setting the minimum width of the groove 2115 to be greater than or equal to 5 mm, the bottom wall 2123 of the groove 2115 can be welded to the first current collector 25 or the first electrode 232. This helps to reduce the difficulty of welding the area of ​​the connection part 2112 thinned by the groove 2115 to the first current collector 25 or the first electrode 232. This effectively alleviates the phenomenon that the bottom wall 2123 of the groove 2115 cannot be welded to the first current collector 25 or the first electrode 232 due to the small width of the groove 2115.

[0151] In some embodiments, along the thickness direction X of the wall portion, the projected area of ​​the groove 2115 is S1, and the projected area of ​​the wall portion 211 is S2, satisfying 0.1S2≤S1≤0.5S2.

[0152] Wherein, the projected area S1 of the groove 2115 is the area of ​​the region defined by the projection of the groove 2115 onto a plane perpendicular to the thickness direction X of the wall. The projected area S2 of the wall 211 is the area of ​​the region defined by the projection of the entire wall 211 onto a plane perpendicular to the thickness direction X of the wall.

[0153] For example, the projected area S1 of the groove 2115 can be 0.1 times, 0.12 times, 0.15 times, 0.18 times, 0.2 times, 0.25 times, 0.3 times, 0.35 times, 0.4 times, 0.45 times, or 0.5 times the projected area S2 of the wall 211.

[0154] By setting the projected area of ​​the groove 2115 in the thickness direction X of the wall portion to be greater than or equal to 0.1 times the projected area of ​​the wall portion 211 in the thickness direction X of the wall portion, the area of ​​the region of the connecting portion 2112 that is thinned by the groove 2115 is increased, thereby effectively increasing the area of ​​the welding connection between the connecting portion 2112 and the first current collector 25 or the first electrode 232, which is beneficial to increasing the flow area between the connecting portion 2112 and the first electrode 232. Furthermore, by setting the projected area of ​​the groove 2115 in the thickness direction X of the wall portion to be less than or equal to 0.5 times the projected area of ​​the wall portion 211 in the thickness direction X of the wall portion, the phenomenon of the groove 2115 occupying too much space on the wall portion 211 can be alleviated. On the one hand, this is beneficial to improve the structural strength of the wall portion 211, thereby reducing the risk of deformation or breakage of the wall portion 211 during use. On the other hand, it can alleviate the phenomenon of excessive connecting parts 2112 protruding from the first surface 2111 of the wall portion 211 in the area corresponding to the groove 2115, which could cause interference between the connecting parts 2112 and other components inside the battery cell 20.

[0155] According to some embodiments of this application, refer to Figure 3 and Figure 4 Please refer to further details. Figure 7 , Figure 7 This is a top view of a battery cell 20 provided in some embodiments of this application. The groove 2115 is an arc-shaped groove extending along an arc trajectory.

[0156] Among them, the groove 2115 is an arc-shaped groove extending along the arc trajectory, that is, the extension direction of the groove 2115 is the trajectory line of the arc, so as to make the groove 2115 arc-shaped groove structure.

[0157] By setting the groove 2115 as an arc-shaped groove structure extending along an arc trajectory, it is easier to process and manufacture, and the range of the area where the bottom wall 2123 of the groove 2115 is welded to the first current collector 25 or the first electrode 232 can be expanded, thereby effectively improving the electrical connection effect between the wall 211 and the first electrode 232.

[0158] In some embodiments, see Figure 3 and Figure 7 As shown, the outer shell 21 is cylindrical, and the central axis of the outer shell 21 extends along the thickness direction X of the wall. The central axis of the outer shell 21 passes through the center of the arc trajectory of the groove 2115.

[0159] The central axis of the outer shell 21 passes through the center of the arc trajectory of the groove 2115. That is, the center of the circle defined by the extended trajectory line of the groove 2115 is located on the central axis of the outer shell 21. In other words, the groove 2115 is an arc-shaped structure that surrounds the central axis of the outer shell 21.

[0160] By setting the outer shell 21 as a cylindrical structure, and the central axis of the outer shell 21 extending along the thickness direction X of the wall, the shape of the wall 211 is circular. Thus, by setting the central axis of the outer shell 21 as the center of the arc trajectory passing through the groove 2115, the groove 2115 is an arc-shaped groove structure surrounding the central axis of the outer shell 21. On the one hand, this is beneficial to improve the space utilization of the groove 2115 on the wall 211. On the other hand, it is easy to manufacture and can further expand the range of the area where the bottom wall 2123 of the groove 2115 is welded to the first current collector 25 or the first electrode 232, thereby improving the electrical connection effect between the wall 211 and the first electrode 232.

[0161] According to some embodiments of this application, see Figure 6 As shown, along the thickness direction X of the wall portion, the dimension of the connecting portion 2112 protruding from the first surface 2111 is D1, which satisfies that D1≤8mm.

[0162] The dimension of the connecting part 2112 protruding from the first surface 2111 is D1. That is, D1 is the distance between the end face of the connecting part 2112 facing the electrode assembly 23 in the thickness direction X of the wall and the first surface 2111.

[0163] For example, the dimension D1 of the connecting portion 2112 protruding from the first surface 2111 can be 0.1mm, 0.2mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm or 8mm, etc.

[0164] By setting the size of the connecting part 2112 protruding from the first surface 2111 to less than or equal to 8mm, on the one hand, the phenomenon of the connecting part 2112 occupying too much space can be reduced, which is conducive to improving the internal space utilization of the battery cell 20. On the other hand, the interference effect caused by the connecting part 2112 on the electrical connection between the electrode terminal 22 and the second tab 233 can be reduced.

[0165] It should be noted that the connecting portion 2112 disposed on the first surface 2111 of the wall portion 211 can be one or more. For example, in Figure 6 and Figure 7 In this configuration, the first surface 2111 has only one protruding connecting portion 2112, and correspondingly, the second surface 2114 has a groove 2115 with the same shape as the connecting portion 2112. Of course, the structure of the battery cell 20 is not limited to this; in some embodiments, please refer to... Figure 8 , Figure 8This is a top view of a battery cell 20 provided in some embodiments of this application. A plurality of connecting portions 2112 are protruding on a first surface 2111. Correspondingly, a plurality of grooves 2115 with the same shape as the connecting portions 2112 are formed on a second surface 2114.

[0166] For example, in Figure 8 In the middle, two grooves 2115 are formed on the second surface 2114 of the wall portion 211. The two grooves 2115 are arranged at intervals along an arc trajectory with the central axis of the outer shell 21 as the center. Correspondingly, two connecting portions 2112 are protruded on the first surface 2111.

[0167] By providing multiple connecting portions 2112 on the first surface 2111 of the wall portion 211, the wall portion 211 can be electrically connected to the first electrode 232 through the multiple connecting portions 2112, which is beneficial to improving the effect of mutual electrical connection between the wall portion 211 and the first electrode 232, and can increase the current flow area between the wall portion 211 and the first electrode 232.

[0168] According to some embodiments of this application, see Figure 5 and Figure 6 As shown, the wall portion 211 is provided with an assembly hole 2113. Along the thickness direction X of the wall portion, the assembly hole 2113 penetrates the wall portion 211. The electrode terminal 22 is disposed in the assembly hole 2113 and protrudes from the first surface 2111.

[0169] The electrode terminal 22 is inserted into the mounting hole 2113 of the wall portion 211, and the electrode terminal 22 protrudes from the first surface 2111. That is, in the thickness direction X of the wall portion, the end of the electrode terminal 22 near the electrode assembly 23 extends out of the mounting hole 2113 and beyond the first surface 2111, so that the end face of the electrode terminal 22 facing the electrode assembly 23 is spaced apart from the first surface 2111.

[0170] By configuring the electrode terminal 22 to protrude from the first surface 2111 in the thickness direction X of the wall portion, it is easier to electrically connect the electrode terminal 22 to the second tab 233. This reduces the difficulty of making an electrical connection between the electrode terminal 22 and the second tab 233. Furthermore, the connecting portion 2112 protruding from the first surface 2111 of the wall portion 211 can compensate for the height difference between the end face of the electrode terminal 22 facing the electrode assembly 23 and the first surface 2111 of the wall portion 211. Thus, while enabling the wall portion 211 to be electrically connected to the first tab 232, the electrical connection effect between the electrode terminal 22 and the second tab 233 can be effectively improved.

[0171] In some embodiments, see Figure 6As shown, along the thickness direction X of the wall portion, the dimension of the protrusion of the first surface 2111 of the connecting portion 2112 is D1, and the dimension of the electrode terminal 22 protruding from the first surface 2111 is D2, satisfying that D1 = D2.

[0172] Where D1 = D2, that is, the height of the connecting part 2112 protruding from the first surface 2111 is equal to the height of the electrode terminal 22 protruding from the first surface 2111, so that in the thickness direction X of the wall, the end face of the connecting part 2112 facing the electrode assembly 23 is flush with the end face of the electrode terminal 22 facing the electrode assembly 23.

[0173] By setting the size of the connecting portion 2112 protruding from the first surface 2111 to be the same as the size of the electrode terminal 22 protruding from the first surface 2111, the end face of the connecting portion 2112 facing the electrode assembly 23 and the end face of the electrode terminal 22 facing the electrode assembly 23 are flush with each other in the thickness direction X of the wall portion. On the one hand, the difficulty of electrical connection between the connecting portion 2112 and the first tab 232 and between the electrode terminal 22 and the second tab 233 can be reduced. On the other hand, the phenomenon of poor electrical connection between the connecting portion 2112 and the first tab 232 or between the electrode terminal 22 and the second tab 233 can be reduced due to the mutual influence between the connecting portion 2112 and the electrode terminal 22.

[0174] According to some embodiments of this application, see Figure 4 , Figure 5 and Figure 6 As shown, the battery cell 20 may further include a first current collector 25 and a second current collector 26. The first current collector 25 is located between the connecting portion 2112 and the first electrode tab 232, and connects the connecting portion 2112 and the first electrode tab 232. The second current collector 26 is located between the electrode terminal 22 and the second electrode tab 233, and is spaced apart from the first current collector 25, and connects the electrode terminal 22 and the second electrode tab 233.

[0175] Along the thickness direction X of the wall portion, the first current collector 25 is disposed between the connecting portion 2112 and the first electrode 232, and the two sides of the first current collector 25 are respectively connected to the connecting portion 2112 and the first electrode 232 to realize the electrical connection between the first electrode 232 and the wall portion 211.

[0176] Optionally, the connection structure between the first current collector 25 and the first electrode 232 can be various, such as welding or abutting. Similarly, the connection structure between the first current collector 25 and the connecting part 2112 can also be various, such as welding or abutting.

[0177] The first current collector 25 serves to electrically connect the first electrode tab 232 and the connection part 2112 of the wall 211. The material of the first current collector 25 can be various, such as copper, iron, aluminum, steel or aluminum alloy.

[0178] Similarly, along the thickness direction X of the wall portion, the second current collector 26 is disposed between the electrode terminal 22 and the second tab 233, and both sides of the second current collector 26 are connected to the electrode terminal 22 and the second tab 233 respectively, so as to realize the electrical connection between the second tab 233 and the electrode terminal 22.

[0179] Optionally, the connection structure between the second current collector 26 and the second electrode tab 233 can be various, such as welding or abutting. Similarly, the connection structure between the second current collector 26 and the electrode terminal 22 can also be various, such as welding or abutting.

[0180] The second current collector 26 serves to electrically connect the second electrode tab 233 and the electrode terminal 22. The material of the second current collector 26 can be various, such as copper, iron, aluminum, steel or aluminum alloy.

[0181] For example, in Figure 5 In the first current collector 25 and the second current collector 26 have the same thickness in the thickness direction X of the wall portion, and the height of the connecting portion 2112 protruding from the first surface 2111 is equal to the height of the electrode terminal 22 protruding from the first surface 2111, so that the first current collector 25 can be connected to the wall portion 211 through the connecting portion 2112, and the second current collector 26 can be connected to the electrode terminal 22.

[0182] By providing a first current collector 25 between the connecting portion 2112 of the wall portion 211 and the first electrode tab 232, and by connecting the connecting portion 2112 and the first electrode tab 232, an electrical connection is achieved between the first electrode tab 232 and the wall portion 211, which helps to reduce the difficulty of electrically connecting the first electrode tab 232 and the connecting portion 2112 to each other. Similarly, by providing a second current collector 26 between the electrode terminal 22 and the second electrode tab 233, and by connecting the electrode terminal 22 and the second electrode tab 233, an electrical connection is achieved between the second electrode tab 233 and the electrode terminal 22, which helps to reduce the difficulty of electrically connecting the second electrode tab 233 and the electrode terminal 22 to each other. In addition, by spaced the first current collector 25 and the second current collector 26 apart, the phenomenon of short circuit between the first current collector 25 and the second current collector 26 is reduced, which helps to reduce the usage risk of the battery cell 20.

[0183] According to some embodiments of this application, see Figure 5 and Figure 6As shown, along the thickness direction X of the wall portion, the first current collector 25 has a third surface 251 facing the wall portion 211, and the third surface 251 is connected to the connecting portion 2112. The second current collector 26 has a fourth surface 261 facing the wall portion 211, and the fourth surface 261 is connected to the electrode terminal 22. The third surface 251 and the fourth surface 261 are flush.

[0184] Wherein, the third surface 251 and the fourth surface 261 are flush, that is, in the thickness direction X of the wall portion, the distance between the first current collector 25 and the first surface 2111 of the wall portion 211 is equal to the distance between the second current collector 26 and the first surface 2111 of the wall portion 211. Thus, by making the height of the connecting portion 2112 protruding from the first surface 2111 equal to the height of the electrode terminal 22 protruding from the first surface 2111, the connection quality between the first current collector 25 and the connecting portion 2112 and between the second current collector 26 and the electrode terminal 22 is improved.

[0185] By setting the third surface 251 of the first current collector 25 to be flush with the fourth surface 261 of the second current collector 26, it is easier to assemble the first current collector 25 and the second current collector 26, which helps to reduce the difficulty of assembling the first current collector 25 and the second current collector 26 between the wall portion 211 and the electrode assembly 23. On the other hand, the connecting portion 2112 provided on the first surface 2111 of the wall portion 211 can compensate for the gap between the first current collector 25 and the wall portion 211, so that the first current collector 25 can be electrically connected to the wall portion 211 and the contact effect between the first current collector 25 and the wall portion 211 can be improved.

[0186] In some embodiments, please continue to see Figure 5 and Figure 6 As shown, along the thickness direction X of the wall portion, the first electrode ear 232 has a fifth surface 2321 facing the wall portion 211, the first current collector 25 is connected to the fifth surface 2321, the second electrode ear 233 has a sixth surface 2331 facing the wall portion 211, the second current collector 26 is connected to the sixth surface 2331, and the fifth surface 2321 is flush with the sixth surface 2331.

[0187] In this embodiment, the fifth surface 2321 and the sixth surface 2331 are flush, meaning that in the thickness direction X of the wall portion, the distance between the first tab 232 and the first surface 2111 of the wall portion 211 is equal to the distance between the second tab 233 and the first surface 2111 of the wall portion 211. Thus, in the embodiment where the third surface 251 of the first current collector 25 and the fourth surface 261 of the second current collector 26 are flush, the first current collector 25 and the second current collector 26 have equal thicknesses and are flush with each other.

[0188] By setting the fifth surface 2321 of the first tab 232 facing the wall portion 211 and the sixth surface 2331 of the second tab 233 facing the wall portion 211 to be flush with each other, it is convenient to process the first tab 232 and the second tab 233. On the other hand, it can realize that the first current collector 25 and the second current collector 26 are flush with each other on the side facing the electrode assembly 23 in the thickness direction X of the wall portion, so as to reduce the positional difference between the first current collector 25 and the second current collector 26 in the thickness direction X of the wall portion. This helps to reduce the difficulty of assembling the first current collector 25 and the second current collector 26 between the electrode assembly 23 and the wall portion 211, and also helps to improve the internal space utilization of the battery cell 20.

[0189] According to some embodiments of this application, refer to Figure 4 and Figure 5 Please refer to further details. Figure 9 and Figure 10 , Figure 9 This is a schematic diagram showing the connection of the first current collector 25 and the second current collector 26 of the battery cell 20, as provided in some embodiments of this application, assembled on the first insulating member 28. Figure 10 This is a schematic diagram of the structure of the first insulating member 28 of the battery cell 20 provided in some embodiments of this application. The battery cell 20 may also include the first insulating member 28, which is disposed between the electrode assembly 23 and the wall portion 211, and the first insulating member 28 insulatingly isolates the first current collector 25 and the second current collector 26.

[0190] The first insulating element 28 serves to provide insulation and isolation for the first current collector 25 and the second current collector 26. The material of the first insulating element 28 can be rubber, silicone or plastic, etc.

[0191] The first insulating member 28 provides insulation and isolation between the first current collector 25 and the second current collector 26. That is, at least a portion of the first insulating member 28 is located between the first current collector 25 and the second current collector 26 so that the first current collector 25 and the second current collector 26 do not come into contact with each other. In other words, the first insulating member 28 can separate the first current collector 25 and the second current collector 26.

[0192] By providing a first insulating member 28 between the electrode assembly 23 and the wall portion 211, and by using the first insulating member 28 to insulate and isolate the first current collector 25 and the second current collector 26, insulation and isolation between the first current collector 25 and the second current collector 26 can be achieved, which helps to further reduce the risk of short circuit between the first current collector 25 and the second current collector 26.

[0193] In some embodiments, please continue to see Figure 4 , Figure 5 , Figure 9 and Figure 10 As shown, the first insulating member 28 is provided with a first mounting hole 281 and a second mounting hole 282 arranged at intervals, the first current collector 25 is provided in the first mounting hole 281, and the second current collector 26 is provided in the second mounting hole 282.

[0194] The first insulating member 28 is provided with first mounting holes 281 and second mounting holes 282 arranged at intervals. That is, the first mounting holes 281 and second mounting holes 282 on the first insulating member 28 do not contact each other, so that the first insulating member 28 can also provide assembly for the first current collector 25 and the second current collector 26. (See also...) Figure 10 As shown, both the first mounting hole 281 and the second mounting hole 282 are structures that penetrate both sides of the first insulating member 28 in the thickness direction X of the wall.

[0195] For example, the first current collector 25 is snapped into the first mounting hole 281. Of course, in other embodiments, the first current collector 25 can also be connected to the first mounting hole 281 by means of adhesive bonding or bolting. Similarly, the second current collector 26 is snapped into the second mounting hole 282. Of course, in other embodiments, the second current collector 26 can also be connected to the second mounting hole 282 by means of adhesive bonding or bolting.

[0196] By providing first mounting holes 281 and second mounting holes 282 spaced apart on the first insulating member 28, and by providing first current collector 25 and second current collector 26 respectively within the first mounting holes 281 and second mounting holes 282, on the one hand, it is possible to assemble the first current collector 25 and second current collector 26 onto the first insulating member 28, so that the first insulating member 28 can provide support and assembly for the first current collector 25 and second current collector 26, which helps to reduce the difficulty of setting the first current collector 25 and second current collector 26 between the wall portion 211 and the electrode assembly 23. On the other hand, it is possible to achieve insulation isolation between the first current collector 25 and second current collector 26 by providing first current collector 25 and second current collector 26 spaced apart on the first insulating member 28.

[0197] In some embodiments, see Figure 9 and Figure 10 As shown, the first insulating member 28 may include a first insulator 283 and a second insulator 284. The first insulator 283 has a ring structure, and the second insulator 284 is connected to 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 second insulator 284 is located between the first current collector 25 and the second current collector 26.

[0198] The first insulator 283 has a ring structure, meaning it is a ring structure with its ends connected. The shape of the first insulator 283 can be various; for example, see [link to example]. Figure 9 and Figure 10 As shown, the first insulator 283 is a circular ring structure, and the first insulator 283 surrounds the outside of the first current collector 25 and the second current collector 26. That is to say, the first insulator 283 is a ring structure, and the first current collector 25 and the second current collector 26 are both located inside the first insulator 283.

[0199] The second insulator 284 is connected to 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 second insulator 284 is located between the first current collector 25 and the second current collector 26. That is, the second insulator 284 is located inside the first insulator 283, and both ends of the second insulator 284 are connected to the inner circumferential surface of the first insulator 283, so as to divide the internal space of the first insulator 283 into two assembly spaces, namely the first mounting hole 281 and the second mounting hole 282.

[0200] Optionally, the first insulator 283 and the second insulator 284 can be an integrally formed structure or a separate structure. For example, in... Figure 10 In this structure, the first insulator 283 and the second insulator 284 are integrally formed. The first insulator 283 and the second insulator 284 can be manufactured by integral forming processes such as injection molding, stamping or extrusion molding.

[0201] 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, so that 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 current collector 25 and the second current collector 26. The first insulating member 28 with this structure can, on the one hand, surround the outside of the first current collector 25 and the second current collector 26 through the first insulator 283, so that the first current collector 25 and the second current collector 26 can be separated from the housing 21, which helps to reduce the risk of short circuit between the first current collector 25 and the second current collector 26 and the housing 21. On the other hand, the second insulator 284 can separate the first current collector 25 and the second current collector 26, which helps to reduce the risk of short circuit between the first current collector 25 and the second current collector 26.

[0202] According to some embodiments of this application, see Figure 3, Figure 4 and Figure 5 As shown, the outer shell 21 is cylindrical, and the central axis of the outer shell 21 extends along the thickness direction X of the wall.

[0203] The outer casing 21 is cylindrical, and the end cap 213 is a circular plate structure so that the battery cell 20 is cylindrical. Similarly, the main body 231 of the electrode assembly 23 is also cylindrical.

[0204] By setting the outer casing 21 to a cylindrical shape, the battery cell 20 can be easily processed to form a cylindrical structure, giving the battery cell 20 advantages such as high capacity, long cycle life, and wide operating temperature range.

[0205] According to some embodiments of this application, see Figure 3 , Figure 4 and Figure 5 As shown, the housing 21 may include a housing 212 and an end cap 213. The housing 212 includes a side wall 2122 and a wall portion 211. The side wall 2122 surrounds the wall portion 211. Along the thickness direction X of the wall portion, one end of the side wall 2122 is connected to the wall portion 211, and the other end forms an opening 2121. The side wall 2122 and the wall portion 211 together define a receiving cavity for accommodating the electrode assembly 23. The end cap 213 closes the opening 2121.

[0206] The sidewall 2122 surrounds the wall portion 211. Along the thickness direction X of the wall portion, one end of the sidewall 2122 is connected to the wall portion 211, and the other end forms an opening 2121. That is, the wall portion 211 is the bottom wall 2123 of the shell 212, which is opposite to the end cap 213 in the thickness direction X of the wall portion. Correspondingly, the end cap 213 covers the opening 2121 at the end of the sidewall 2122 away from the wall portion 211.

[0207] Optionally, the sidewalls 2122 and wall portions 211 of the housing 212 can be either separate structures or integral structures. For example, in... Figure 4 In this embodiment, the sidewall 2122 and the wall portion 211 of the housing 212 are integrally formed, and the housing 212 can be manufactured by integral forming processes such as stamping, casting or extrusion molding. In an embodiment where the sidewall 2122 and the wall portion 211 of the housing 212 are separate, the wall portion 211 can be connected to the end away from the end cap 213 by means of welding, bonding or snap-fitting.

[0208] By setting the wall portion 211 of the outer casing 21 as the bottom wall 2123 opposite to the end cap 213, the wall portion 211, which is used to set the electrode terminals 22 and for electrical connection with the first tab 232, can be moved away from the end cap 213. This reduces the impact of stress generated when the end cap 213 and the outer casing 212 are connected to each other on the wall portion 211 or the electrode terminals 22 set on the wall portion 211, which is beneficial to improving the reliability and service life of the battery cell 20.

[0209] 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 outer casing 21 can include a housing 212 and an end cap 213. The housing 212 has an internal cavity with an opening 2121 for accommodating the electrode assembly 23. The end cap 213 closes the opening 2121 and is a wall portion 211. That is, the electrode terminals 22 are insulatedly mounted on the end cap 213, and a connecting portion 2112 protrudes from the side of the end cap 213 facing the electrode assembly 23.

[0210] By setting the wall portion 211 of the outer casing 21 as an end cap 213 for closing the opening 2121 of the casing 212, the battery cell 20 with this structure is easy to assemble the electrode terminals 22 on the end cap 213, and can reduce the difficulty of electrically connecting the first tab 232 and the second tab 233 to the end cap 213 and the electrode terminals 22 respectively, thereby reducing the manufacturing difficulty of the battery cell 20 and improving the production efficiency of the battery cell 20.

[0211] According to some embodiments of this application, this application also provides a battery 100, which includes a battery cell 20 of any of the above schemes.

[0212] Among them, see Figure 2 As shown, the battery 100 may also include a housing 10, in which the battery cells 20 are housed.

[0213] In some embodiments, the housing 10 may include a first housing body 11 and a second housing body 12, the first housing body 11 and the second housing body 12 covering each other, the first housing body 11 and the second housing body 12 together defining an assembly space for accommodating the battery cell 20.

[0214] 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. 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 together define the 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.

[0215] Of course, the box 10 formed by the first box body 11 and the second box body 12 can be of various shapes, such as a cylinder or a cuboid. For example, in... Figure 2 In the middle, box 10 has a rectangular structure.

[0216] Optionally, the battery cell 20 disposed within the housing 10 can be one or more. For example, in... Figure 2 In this battery 100, multiple battery cells 20 are arranged inside the casing 10. These battery cells 20 can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that some of the battery cells 20 are connected in series and others in parallel. The multiple battery cells 20 can be directly connected in series, parallel, or in a mixed configuration, and then the entire assembly of the multiple battery cells 20 is housed inside the casing 10. Alternatively, the battery 100 can also be composed of multiple battery cells 20 first connected in series, parallel, or in a mixed configuration to form a battery module, and then multiple battery modules are connected in series, parallel, or in a mixed configuration to form a whole, which is then housed inside the casing 10.

[0217] The battery 100 may also include other structures. For example, the battery 100 may also include a busbar component that connects multiple battery cells 20 to achieve electrical connection between the multiple battery cells 20.

[0218] It should be noted that in some embodiments, the battery 100 may not have a housing 10. The battery 100 includes multiple battery cells 20, and the battery 100 composed of multiple battery cells 20 can be directly mounted onto an electrical device to provide power to the electrical device through the multiple battery cells 20. That is, the housing 10 can be part of the electrical device. Taking a vehicle 1000 as an example, the housing 10 can be part of the chassis structure of the vehicle 1000. For example, a portion of the housing 10 can be at least a part of the floor of the vehicle 1000, or a portion of the housing 10 can be at least a part of the crossbeams and longitudinal beams of the vehicle 1000.

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

[0220] The electrical device can be any of the aforementioned devices or systems that utilize battery cells 20.

[0221] According to some embodiments of this application, see Figures 3 to 7 as well as Figures 9 to 10As shown, this application provides a battery cell 20, which includes a housing 21, electrode terminals 22, electrode assembly 23, a first current collector 25, a second current collector 26, and a first insulating member 28. The housing 21 includes a shell 212 and an end cap 213. The housing 21 has a wall portion 211. The shell 212 includes a side wall 2122 and a bottom wall 2123. The side wall 2122 surrounds the bottom wall 2123. Along the thickness direction X of the wall portion, one end of the side wall 2122 is connected to the bottom wall 2123, and the other end forms an opening 2121. The side wall 2122 and the bottom wall 2123 together define a receiving cavity. The bottom wall 2123 is the wall portion 211, and the end cap 213 closes the opening 2121. Along the thickness direction X of the wall portion, the wall portion 211 has a first surface 2111 facing the receiving cavity and a second surface 2114 facing away from the receiving cavity. A connecting portion 2112 protrudes from the first surface 2111, and a groove 2115 is formed on the second surface 2114 corresponding to the position of the connecting portion 2112. The shape of the groove 2115 is the same as the shape of the connecting portion 2112. The minimum width of the groove 2115 is W, which satisfies W≥5mm. Along the thickness direction X of the wall portion, the projected area of ​​the groove 2115 is S1, and the projected area of ​​the wall portion 211 is S2, which satisfies 0.1S2≤S1≤0.5S2. The groove 2115 is an arc-shaped groove extending along an arc trajectory. The outer shell 21 is cylindrical, and the central axis of the outer shell 21 extends along the thickness direction X of the wall portion, passing through the center of the arc trajectory of the groove 2115. Along the thickness direction X of the wall portion, the dimension of the connecting portion 2112 protruding from the first surface 2111 is D1, which satisfies D1≤8mm. The electrode terminal 22 is insulatedly mounted on the wall portion 211. The wall portion 211 is provided with a mounting hole 2113. Along the thickness direction X of the wall portion, the mounting hole 2113 penetrates the wall portion 2111. The electrode terminal 22 is disposed in the mounting hole 2113 and protrudes from the first surface 2111. The dimension of the connecting portion 2112 protruding from the first surface 2111 is D1, and the dimension of the electrode terminal 22 protruding from the first surface 2111 is D2, which satisfies D1=D2. Electrode assembly 23 is housed within the receiving cavity of housing 21. Electrode assembly 23 includes a main body 231, a first electrode tab 232, and a second electrode tab 233. The main body 231 is cylindrical, and its central axis extends along the thickness direction X of the wall. The first electrode tab 232 and the second electrode tab 233 have opposite polarities. Along the thickness direction X of the wall, both the first electrode tab 232 and the second electrode tab 233 are disposed at the end of the main body 231 facing the wall 211. A first current collector 25 is located between the connecting part 2112 and the first electrode tab 232. The bottom wall 2123 of the groove 2115 is welded to the first current collector 25, and the first current collector 25 is connected to the first electrode tab 232 to electrically connect the first electrode tab 232 and the wall 211.The second current collector 26 is located between the electrode terminal 22 and the second tab 233. The second current collector 26 is spaced apart from the first current collector 25. The second current collector 26 connects the electrode terminal 22 and the second tab 233 to electrically connect the electrode terminal 22 and the second tab 233. Along the thickness direction X of the wall portion, the first current collector 25 has a third surface 251 facing the wall portion 211, and the third surface 251 is connected to the connecting portion 2112. The second current collector 26 has a fourth surface 261 facing the wall portion 211, and the fourth surface 261 is connected to the electrode terminal 22. The third surface 251 and the fourth surface 261 are flush. Along the thickness direction X of the wall portion, the first electrode ear 232 has a fifth surface 2321 facing the wall portion 211, the first current collector 25 is connected to the fifth surface 2321, the second electrode ear 233 has a sixth surface 2331 facing the wall portion 211, the second current collector 26 is connected to the sixth surface 2331, and the fifth surface 2321 is flush with the sixth surface 2331. The first insulating element 28 is disposed between the electrode assembly 23 and the wall portion 211. The first insulating element 28 includes a first insulator 283 and a second insulator 284. The first insulator 283 has an annular structure. The second insulator 284 is connected to 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. A first current collector 25 is disposed in the first mounting hole 281, and a second current collector 26 is disposed in the second mounting hole 282. The first insulator 283 surrounds the outside of the first current collector 25 and the second current collector 26, and the second insulator 284 is located between the first current collector 25 and the second current collector 26.

[0222] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0223] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized in that, include: The outer shell has walls; Electrode terminals are insulated and mounted on the wall portion; as well as An electrode assembly is housed within the housing. The electrode assembly includes a main body, a first electrode tab, and a second electrode tab. The first electrode tab and the second electrode tab have opposite polarities. Along the thickness direction of the wall portion, both the first electrode tab and the second electrode tab are disposed at the end of the main body portion facing the wall portion. Along the thickness direction of the wall portion, the wall portion has a first surface facing the electrode assembly and a second surface facing away from the first surface. A connecting portion is protruding on the first surface, and a groove is formed on the second surface corresponding to the position of the connecting portion. The connecting portion is electrically connected to the first electrode tab, and the electrode terminal is electrically connected to the second electrode tab. The battery cell further includes a first current collector, which is connected to the first tab. The bottom wall of the groove is welded to the first current collector to electrically connect the first tab and the wall, or the bottom wall of the groove is welded to the first tab to electrically connect the first tab and the wall. Along the thickness direction of the wall portion, the projected area of ​​the groove is S1, and the projected area of ​​the wall portion is S2, satisfying 0.1S2≤S1≤0.5S2.

2. The battery cell according to claim 1, characterized in that, The minimum width of the groove is W, which satisfies W≥5mm.

3. The battery cell according to claim 1, characterized in that, The groove is an arc-shaped groove extending along a circular arc trajectory.

4. The battery cell according to claim 3, characterized in that, The outer shell is cylindrical, and the central axis of the outer shell extends along the thickness direction of the wall portion, passing through the center of the circular arc trajectory of the groove.

5. The battery cell according to claim 1, characterized in that, Along the thickness direction of the wall portion, the dimension of the connecting portion protruding from the first surface is D1, which satisfies D1≤8mm.

6. The battery cell according to claim 1, characterized in that, The first surface is provided with a plurality of the connecting portions.

7. The battery cell according to claim 1, characterized in that, The wall portion is provided with an assembly hole, which extends through the wall portion along its thickness direction. The electrode terminal is disposed within the assembly hole and protrudes from the first surface.

8. The battery cell according to claim 7, characterized in that, Along the thickness direction of the wall portion, the dimension of the connecting portion protruding from the first surface is D1, and the dimension of the electrode terminal protruding from the first surface is D2, satisfying that D1 = D2.

9. The battery cell according to any one of claims 1-8, characterized in that, The battery cell also includes: A first current collector is located between the connecting portion and the first electrode tab, and the first current collector connects the connecting portion and the first electrode tab. The second current collector is located between the electrode terminal and the second tab, and is spaced apart from the first current collector. The second current collector connects the electrode terminal and the second tab.

10. The battery cell according to claim 9, characterized in that, Along the thickness direction of the wall portion, the first current collector has a third surface facing the wall portion, the third surface being connected to the connecting portion, and the second current collector has a fourth surface facing the wall portion, the fourth surface being connected to the electrode terminal; The third surface and the fourth surface are flush.

11. The battery cell according to claim 9, characterized in that, Along the thickness direction of the wall portion, the first electrode tab has a fifth surface facing the wall portion, the first current collector is connected to the fifth surface, and the second electrode tab has a sixth surface facing the wall portion, the second current collector is connected to the sixth surface; The fifth surface is flush with the sixth surface.

12. The battery cell according to claim 9, characterized in that, The battery cell also includes: A first insulating element is disposed between the electrode assembly and the wall portion, wherein the first insulating element provides insulation and isolation between the first current collector and the second current collector.

13. The battery cell according to claim 12, characterized in that, The first insulating member is provided with a first mounting hole and a second mounting hole arranged at intervals, the first current collector is disposed in the first mounting hole, and the second current collector is disposed in the second mounting hole.

14. The battery cell according to claim 13, characterized in that, The first insulating element includes: The first insulator has a ring structure; A second insulator is connected to the first insulator, the second insulator being configured to divide the internal space of the first insulator into the first mounting hole and the second mounting hole, the second insulator being located between the first current collector and the second current collector.

15. The battery cell according to claim 1, characterized in that, The outer shell is cylindrical, and the central axis of the outer shell extends along the thickness direction of the wall portion.

16. The battery cell according to claim 1, characterized in that, The outer casing includes: The housing includes a sidewall and the wall portion, the sidewall surrounding the wall portion, one end of the sidewall being connected to the wall portion along the thickness direction of the wall portion, and the other end forming an opening, the sidewall and the wall portion together defining a receiving cavity for accommodating the electrode assembly; End cap, to close the opening.

17. The battery cell according to claim 1, characterized in that, The outer casing includes: The housing has an internally formed receiving cavity with an opening for accommodating the electrode assembly; End cap, to close the opening; The end cap is the wall portion.

18. A battery, characterized in that, Includes the battery cell as described in any one of claims 1-17.

19. An electrical appliance, characterized in that, Includes a battery cell as described in any one of claims 1-17, the battery cell being used to provide electrical energy.

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