Battery monomer, end cover assembly, battery device and power utilization device

Abstract

The embodiment of the utility model discloses a battery monomer, an end cover assembly, a battery device and a power utilization device, the battery monomer comprises a shell, an accommodating cavity is formed, the shell comprises a first wall, and a first through hole is formed in the first wall; the electrode assembly is accommodated in the accommodating cavity; the orthographic projection, facing the first wall, of the first electrode terminal covers the first through hole, the first electrode terminal comprises a main body part and a peripheral part, the peripheral part is connected to the main body part, and at least part of the peripheral part is overlapped with the first wall in the thickness direction; wherein a first groove is formed in one side, facing the first wall, of the peripheral part, and at least part of the first groove is overlapped with the first wall along the thickness direction, so that the stability of the battery monomer is improved.

Description

Technical Field

[0001] This application relates to the field of batteries, and more specifically, to a battery cell, an end cap assembly, a battery device, and an electrical device. Background Technology

[0002] As the application fields of power batteries continue to expand, the market demand for them is also constantly increasing. Correspondingly, the requirements for the stability of power batteries are also rising. Currently used battery cells are prone to casing corrosion during use, leading to reduced stability.

[0003] Therefore, improving the stability of individual battery cells has become an urgent problem to be solved. Utility Model Content

[0004] This application provides a battery cell, an end cap assembly, a battery device, and an electrical device, which can improve the stability of the battery cell.

[0005] In a first aspect, this application provides a battery cell, comprising: a housing forming a receiving cavity, the housing including a first wall having a first through hole; an electrode assembly housed within the receiving cavity; a first electrode terminal, the first electrode terminal having its orthographic projection toward the first wall covering the first through hole, the first electrode terminal including a main body portion and a peripheral portion, the peripheral portion being connected to the main body portion, the peripheral portion at least partially overlapping the first wall along the thickness direction; wherein, a first groove is provided on the side of the peripheral portion facing the first wall, the first groove at least partially overlapping the first wall along the thickness direction.

[0006] In this embodiment, the first electrode terminal covers the side of the first through hole away from the electrode assembly, and the portion of the first electrode terminal opposite to the first wall is provided with a first groove, which reduces the possibility of short circuit in the periphery between the side of the first wall away from the electrode assembly and the side of the first electrode terminal facing the electrode assembly, thereby improving the stability of the battery cell.

[0007] In some embodiments, the battery cell further includes an insulating component disposed between the first electrode terminal and the end cap, wherein the insulating component is at least partially disposed within the first groove.

[0008] In the embodiments provided in this application, the insulating component is at least partially disposed in the first groove, which further increases the creepage distance between the first electrode terminal and the side of the first wall away from the electrode assembly, thereby further reducing the possibility of short circuit between the first electrode terminal and the first wall and improving the stability of the battery cell in use.

[0009] In some embodiments, the battery cell further includes a sealing member, wherein the outer edge of the sealing member projecting toward the first wall surrounds the first through hole, and the inner edge of the sealing member projecting toward the first wall is within the range of the first through hole.

[0010] In this embodiment, the outer edge of the sealing member's orthographic projection onto the first wall surrounds the first through hole, and the inner edge of the sealing member's orthographic projection onto the first wall is within the range of the first through hole. The sealing member can cover the portion of the periphery facing the first wall, thereby further reducing the possibility of short circuit between the first electrode terminal and the first wall.

[0011] In some embodiments, a protruding structure is provided on the side of the first wall facing the first electrode terminal, the protruding structure surrounds the first through hole, and a sealing member is disposed between the protruding structure and the periphery, such that the protruding structure presses the sealing member onto the first electrode terminal.

[0012] In some embodiments, the distance between the inner and outer edges of the protrusion structure as projected in the first wall thickness direction is greater than 0.3 mm.

[0013] In this embodiment, the distance d1 between the inner and outer edges of the protruding structure in the thickness direction of the end cap is greater than 0.3 mm, which allows the sealing component to be more firmly pressed against the first electrode terminal by the protruding structure, thereby providing a good sealing effect and reducing the leakage of electrolyte inside the battery cell.

[0014] In some embodiments, the outer edge of the sealing member projecting toward the first wall surrounds the inner edge of the first groove projecting toward the first wall.

[0015] In this embodiment, the volume of the portion of the sealing component outside the first through hole is greater than or equal to the volume of the gap between the portion of the periphery without a groove and the first wall. After compression, the sealing component can cover the portion of the periphery close to the first wall, thereby covering the space where dendrite overlap is more likely to form, reducing the possibility of short circuit between the first wall and the first electrode terminal.

[0016] In some embodiments, the first groove is an annular groove, the first through hole is a circular through hole, the distance between the periphery and the first wall is H1, the inner diameter of the first groove projected onto the first wall is R1, the radius of the first through hole is R2, and the volume V1 of the sealing component outside the first through hole satisfies V1≥H1×π(R1) / 2. 2 -R2 2 ), where π is the ratio of a circle's diameter to its circumference.

[0017] In this embodiment of the application, by designing and calculating the volume of the sealing component, a reference can be provided for the selection of the sealing component before assembly, thereby reducing sealing problems after assembly or product defects caused by insufficient compression allowance of the sealing component during use.

[0018] In some embodiments, the first groove is an annular groove, the first through hole is a circular through hole, the distance between the periphery and the first wall is H1, the inner diameter of the first groove projected onto the first wall is R1, the radius of the first through hole is R2, and the volume V1 of the sealing component outside the first through hole satisfies V1≥(H1+H2)×π(R1) 2 -R2 2 ), where π is the ratio of a circle to a circle, and H2 satisfies 0.01mm < H2 < 0.3mm.

[0019] In this embodiment, by incorporating a springback allowance into the design of the sealing component, the sealing component can still perform its effective sealing function even if springback occurs during use, thereby improving the stability of the battery cell.

[0020] In some embodiments, the end cap has a second groove on the side facing the first electrode terminal, the second groove surrounds the first through hole, and the sealing member is at least partially accommodated in the second groove.

[0021] In this embodiment, a groove is provided on the side of the first wall facing the first electrode terminal to accommodate a portion of the sealing component. The sealing component can undergo volume flow during deformation, thereby reducing the compression restriction of the sealing component caused by overpressure, and thus reducing the problem of reduced airtightness of the battery cell due to the aging process of the sealing component.

[0022] In some embodiments, a protruding structure is provided on the side of the first wall facing the first electrode terminal, the protruding structure surrounds the first through hole, and the second groove is further away from the first through hole relative to the protruding structure.

[0023] In some embodiments, a limiting portion is provided on the periphery, which cooperates with an insulating component to restrict the movement of the first electrode terminal in the circumferential direction.

[0024] In some embodiments, the limiting portion includes a notch disposed circumferentially along the first electrode terminal, and the insulating component at least partially fills the notch to restrict the movement of the first electrode terminal circumferentially.

[0025] In some embodiments, the first electrode terminal is a negative electrode terminal.

[0026] When the negative electrode terminal is short-circuited to the first wall, the casing may become negatively charged, making it more susceptible to corrosion. When the casing material includes aluminum, the aluminum can also react with lithium ions in the lithium battery to form a lithium-aluminum alloy, leading to casing corrosion and leakage. Therefore, when the first electrode terminal is the negative electrode terminal, reducing the likelihood of a short circuit between the first wall and the first electrode terminal can more effectively suppress casing corrosion.

[0027] In some embodiments, the first wall is further provided with a liquid injection hole, which is located at the end of the first wall away from the first electrode terminal.

[0028] In a second aspect, an end cap assembly is provided for a battery cell. The battery cell includes a housing and an electrode assembly. The housing is a hollow structure with an opening, and the electrode assembly is housed within the housing. The end cap assembly includes: an end cap that covers the opening and has a first through hole; and a first electrode terminal that covers the side of the first through hole away from the electrode assembly. The side of the first electrode terminal facing the electrode assembly includes a central region and an edge region, with the edge region being further away from the electrode assembly than the central region.

[0029] Thirdly, a battery device is provided, comprising a battery cell of the first aspect or any embodiment of the first aspect.

[0030] Fourthly, an electrical device is provided, comprising: a battery cell of the first aspect or any embodiment of the first aspect; and a battery device of the third aspect or any embodiment of the third aspect, wherein the battery cell or battery device is used to provide electrical energy.

[0031] In some embodiments, the electrical device is a vehicle, a ship, or a spacecraft. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of a vehicle according to one embodiment of this application;

[0033] Figure 2 This is a schematic diagram of the structure of a battery device according to an embodiment of this application;

[0034] Figure 3 A perspective view of a battery cell provided in an embodiment of this application is shown;

[0035] Figure 4 An exploded view of a battery cell provided in an embodiment of this application is shown;

[0036] Figure 5 An exploded view of an end cap assembly provided in one embodiment of this application is shown;

[0037] Figure 6 This is a top view of a battery cell provided in an embodiment of this application;

[0038] Figure 7 yes Figure 6 AA cross-sectional view of a single battery cell in the diagram;

[0039] Figure 8 yes Figure 6 CC cross-sectional view of a single battery cell in the image;

[0040] Figure 9 This is a schematic diagram of the electrode terminals in a battery cell provided in an embodiment of this application;

[0041] Figure 10 This is a schematic diagram of the electrode terminals in a battery cell provided in an embodiment of this application;

[0042] Figure 11 A schematic diagram of the electrode terminals in a battery cell provided in an embodiment of this application is shown;

[0043] Figure 12 A schematic diagram of the electrode terminals in a battery cell provided in an embodiment of this application is shown;

[0044] Figure 13 A schematic diagram of the electrode terminals in a battery cell provided in an embodiment of this application is shown;

[0045] Figure 14 A schematic diagram of the electrode terminals in a battery cell provided in an embodiment of this application is shown;

[0046] Figure label:

[0047] 1-Vehicle; 10-Battery unit; 20-Battery cell; 21-Casing; 22-Electrode assembly; 23-Connecting member; 24-Base plate; 26-Sealing component; 30-Controller; 40-Motor; 11-Box; 111-First box section; 112-Second box section; 210-First wall; 211-Casing; 212-End cap; 213-Pressure relief mechanism; 214-Electrode terminal; 214a-First electrode terminal; 214b - Second electrode terminal; 215 - Liquid injection hole; 216 - Support component; 221 - Electrode tab; 221a - First electrode tab; 221b - Second electrode tab; 222 - Body portion; 2121 - First through hole; 2122 - Protrusion structure; 2123 - Second groove; 2131 - Protective structure; 2141 - Peripheral portion; 2142 - Main body portion; 2143 - Insulating component; 2144 - First groove; 2145 - Limiting portion;

[0048] The accompanying drawings are not drawn to scale. Detailed Implementation

[0049] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0050] 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.

[0051] 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.

[0052] In this application, the reference to "embodiment" means that a specific 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 throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] In this application, "multiple" refers to two or more (including two), and similarly, "multiple groups" refers to two or more (including two), and "multiple pieces" refers to two or more (including two).

[0057] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0058] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0059] 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.

[0060] 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.

[0061] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator, with the separator positioned between the positive and negative electrodes. 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.

[0062] 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.

[0063] 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.

[0064] As an example, the positive current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0065] 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 At least one of the following: lithium nickel cobalt aluminum oxides (such as LiNi0.8Co0.15Al0.05O2) and their modified compounds. Modified compounds refer to substances obtained by doping or coating, etc., based on the aforementioned substances.

[0066] 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, a positive electrode active material is filled and / or deposited within the foamed metal.

[0067] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0068] As an example, the negative electrode current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. The composite current collector may include a polymer material substrate and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0069] 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.

[0070] 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.

[0071] 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 negative electrode active materials for battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0072] In some embodiments, the negative 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 negative electrode sheet, the surface of the foamed metal may or may not have a negative electrode active material.

[0073] As an example, negative electrode active materials can be filled or / and deposited within the negative electrode current collector.

[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. This application does not impose any particular limitation on the type of separator membrane; any known porous separator membrane with good chemical and mechanical stability can be selected.

[0077] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separator can be a single component located between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes. An inorganic particle coating, an organic particle coating, or an organic / inorganic composite coating can also be applied to the surface of the separator.

[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. This application does not impose specific limitations on the type of electrolyte; it can be selected according to requirements. The electrolyte can be liquid, gel, or solid.

[0080] Liquid electrolytes include electrolyte salts and solvents.

[0081] In some embodiments, the electrolyte salt may be selected from 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.

[0082] In some embodiments, the solvent may be selected from at least one of 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 of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0083] In some embodiments, the electrolyte may optionally include additives. For example, additives may include negative electrode film-forming additives, positive electrode film-forming additives, and additives that can improve certain properties of the battery cell, such as additives that improve the overcharge / fast charge performance of the battery cell, additives that improve the high-temperature performance of the battery cell, and additives that improve the low-temperature performance of the battery cell.

[0084] The gel electrolyte includes a polymer as a backbone network and can be used in conjunction with an ionic liquid-lithium salt.

[0085] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0086] As an example, the polymers of polymeric solid electrolytes may include polyethers (polyoxyethylene), polysiloxanes, polycarbonates, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids, cellulose, etc.

[0087] As an example, inorganic solid electrolytes can be 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-phosphorus-sulfur, sulfosilium-germanium), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0088] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0089] The electrode assembly can be a wound structure, a stacked structure, or a hybrid structure of wound and stacked.

[0090] In some implementations, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0091] In some implementations, the electrode assembly is a stacked structure.

[0092] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0093] As an example, multiple positive electrode plates can be provided, and negative electrode plates can be folded to form multiple stacked folded segments, with a positive electrode plate sandwiched between adjacent folded segments.

[0094] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0095] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0096] As an example, the separators can be continuously arranged, either by folding or rolling between any adjacent positive or negative electrode plates.

[0097] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0098] 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.

[0099] In some embodiments, the battery cell may include a casing. The casing may be a steel casing, an aluminum casing, a plastic casing (such as a polypropylene casing), a composite metal casing (such as a copper-aluminum composite casing), or an aluminum-plastic film, etc. In some embodiments, the casing may be a sealed structure or a non-sealed structure. As an example, when the casing is a non-sealed structure, the casing serves to protect the electrode assembly, and a sealing bag is included between the casing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag may be a bag-shaped insulating component or an aluminum-plastic film. When the casing is a sealed structure, it is used to encapsulate components such as the electrode assembly and electrolyte.

[0100] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries. This application does not have any particular limitations.

[0101] In some embodiments, the housing includes an end cap and a housing, the housing having an opening, and the end cap covering the opening. The housing may have one or more openings. The end cap may also have one or more.

[0102] In some embodiments, at least one electrode terminal is provided on the housing, and the electrode terminal is electrically connected to the tab. The electrode terminal can be directly connected to the tab, or it can be indirectly connected to the tab through a current collector. The electrode terminal can be provided on the end cap or on the housing.

[0103] In some embodiments, a pressure relief mechanism is provided on the casing. The pressure relief mechanism is used to release the internal gas of the battery cell.

[0104] As an example, the internal pressure or temperature of a battery cell is actuated to release the internal pressure or temperature when it reaches a predetermined threshold. When the internal pressure or temperature of the battery cell reaches the predetermined threshold, the pressure relief mechanism is activated or a weak structure in the pressure relief mechanism is broken, thereby creating an opening or channel for the internal pressure or temperature to be released. The threshold design varies depending on the design requirements. The threshold may depend on the materials of one or more of the positive electrode, negative electrode, electrolyte, and separator in the battery cell.

[0105] As an example, the pressure relief mechanism can be integrally molded with the housing.

[0106] As an example, the pressure relief mechanism can also be separately installed and connected to the housing.

[0107] The term "actuation" as used in this application refers to the activation or actuation of the pressure relief mechanism to a certain state, thereby releasing the internal pressure and temperature of the battery cell. The actions of the pressure relief mechanism may include, but are not limited to: movement of components within the mechanism to form an exhaust channel, rupture, breakage, tearing, or opening of at least a portion of the mechanism, etc. When the pressure relief mechanism is activated, the high-temperature, high-pressure substances inside the battery cell are discharged as waste from the activated portion. This method allows for pressure and temperature relief of the battery cell under controllable pressure or temperature, thereby preventing potentially more serious accidents.

[0108] In some embodiments, when the housing is a non-sealed structure, the pressure relief mechanism can be configured as a through hole for venting gas inside the battery cell.

[0109] The emissions from battery cells mentioned in this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, etc.

[0110] The battery device mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0111] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells.

[0112] As an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form an independent module. As another example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0113] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cell assemblies housed within the housing.

[0114] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0115] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0116] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first enclosure may be a top cover or a bottom plate.

[0117] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0118] 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.

[0119] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use individual battery cells, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft.

[0120] Currently, judging from market trends, the application of power batteries is becoming increasingly widespread. Power batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of power battery applications, market demand is also constantly increasing. Correspondingly, the need for stability in power batteries is also increasing.

[0121] This application provides a battery cell, an end cap assembly, a battery device, and an electrical device. The battery cell includes a housing, an electrode assembly, an end cap, and a first electrode terminal. The housing may be a hollow structure with an opening. The electrode assembly is housed within the housing. The end cap covers the opening of the housing and has a first through hole. The first electrode terminal covers the side of the first through hole away from the electrode assembly. The side of the first electrode terminal facing the electrode assembly includes a central region and an edge region. The edge region is further away from the electrode assembly than the central region.

[0122] In this embodiment, the first electrode terminal covers the side of the first through hole away from the electrode assembly, and the edge region on the side facing the electrode assembly is further away from the electrode assembly, thereby increasing the distance between the edge region and the end cover. This reduces the possibility of short-circuiting between the side of the end cover away from the electrode assembly and the side of the first electrode terminal facing the electrode assembly in the edge region, thereby improving the stability of the battery cell.

[0123] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery devices.

[0124] Electrical equipment can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the above-mentioned electrical equipment.

[0125] For ease of explanation, the following embodiments use a vehicle as an example of electrical equipment.

[0126] For example, such as Figure 1 The diagram shown is a structural schematic of a vehicle 1 according to one embodiment of this application. Vehicle 1 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 motor 40, a controller 30, and a battery device 10 can be installed inside vehicle 1. The controller 30 controls the battery device 10 to supply power to the motor 40. For example, the battery device 10 can be installed at the bottom, front, or rear of vehicle 1. The battery device 10 can be used to power vehicle 1. For example, the battery device 10 can serve as the operating power source for vehicle 1, for example, to meet the electrical system requirements of vehicle 1, such as for starting, navigation, and operation. In another embodiment of this application, the battery device 10 can not only serve as the operating power source for vehicle 1, but also as the driving power source for vehicle 1, replacing or partially replacing gasoline or natural gas to provide driving power for vehicle 1.

[0127] For example. Figure 2 A partial structural schematic diagram of the battery device 10 according to an embodiment of this application is shown. Figure 2 As shown, the battery device 10 of this application embodiment may include a plurality of battery cells 20 to meet different power usage requirements. The shape of the battery cell 20 in this application embodiment can be set according to actual application. For example, the battery cell 20 can be as follows: Figure 2 The cylindrical shape shown, or it could be different. Figure 2 The embodiments shown may be cuboids or other shapes, but are not limited to these.

[0128] It should be understood that, such as Figure 2As shown, the battery device 10 of this embodiment may further include a housing 11, which can be used to accommodate multiple battery cells 20. The housing 11 of this embodiment has a hollow interior, and the multiple battery cells 20 are accommodated within the housing 11. The housing 11 may include two parts, referred to herein as a first housing portion 111 and a second housing portion 112, which are fastened together. The shapes of the first housing portion 111 and the second housing portion 112 can be determined according to the shape of the components housed inside, for example, according to the shape of the combination of the multiple battery cells 20 housed inside. At least one of the first housing portion 111 and the second housing portion 112 has an opening. For example, as... Figure 2 As shown, the first housing portion 111 and the second housing portion 112 can both be hollow cuboids with one open side each. The openings of the first housing portion 111 and the second housing portion 112 are opposite to each other, and the first housing portion 111 and the second housing portion 112 are interlocked to form a housing 11 with a closed chamber, which can be used to accommodate multiple battery cells 20. The multiple battery cells 20 are connected in parallel, series, or mixed and placed inside the housing 11 formed by the interlocking of the first housing portion 111 and the second housing portion 112.

[0129] For example, unlike Figure 2 As shown, either the first housing portion 111 or the second housing portion 112 may have only one hollow cuboid with an opening, while the other is plate-shaped to cover the opening. Taking the second housing portion 112 as a hollow cuboid with one opening and the first housing portion 111 as a plate-shaped example, then the first housing portion 111 covers the opening of the second housing portion 112 to form a housing 11 with a closed chamber, which can be used to accommodate multiple battery cells 20.

[0130] Please refer to the following together. Figure 3 and Figure 4 This application describes a battery cell provided in one embodiment. Further reference is also provided. Figure 5 This application describes an embodiment of the end cap assembly in a battery cell.

[0131] Figure 3 A perspective view of a battery cell provided in an embodiment of this application is shown. Figure 4 An exploded view of a battery cell provided in one embodiment of this application is shown. Figure 5 An exploded view of an end cap assembly provided in one embodiment of this application is shown.

[0132] like Figure 3 and Figure 4As shown, a battery cell according to some embodiments of this application includes a housing 21 and an electrode assembly 22. The housing 21 may include a shell 211 and an end cap 212. Specifically, the shell 211 may be a hollow structure with an opening, and the end cap 212 may cover the opening of the shell 211 so that the electrode assembly 22 can be accommodated within the shell 21. The bottom wall of the shell 211 may be integrally formed with the other walls of the shell 211, or the bottom wall of the shell 211 may be formed independently of the other walls and then welded to the other walls. This application does not limit this aspect.

[0133] Corresponding to different shapes of battery cells 20, the casing 211 of the battery cell 20 can be of various shapes, such as a cylinder or a polygonal prism. For example, as shown... Figure 3 and Figure 4 As shown, in this embodiment, the description mainly uses a hollow cuboid structure for the housing 211. Alternatively, this embodiment mainly uses a hollow structure with an opening at one end for the housing 211. However, the relevant descriptions of this embodiment are also applicable to battery cells 20 of other shapes; for the sake of brevity, they will not be elaborated upon here.

[0134] In some implementations, such as Figure 3 and Figure 4 As shown, the housing 21 is provided with at least two electrode terminals 214, each including at least one first electrode terminal 214a and at least one second electrode terminal 214b, wherein the first electrode terminal 214a and the second electrode terminal 214b have opposite polarities. For example, the first electrode terminal 214a can be a positive electrode terminal, and the second electrode terminal 214b can be a negative electrode terminal; or, the first electrode terminal 214a can be a negative electrode terminal, and the second electrode terminal 214b can be a positive electrode terminal. The electrode assembly 22 may include a body portion 222 and at least two tabs 221, each including at least one first tab 221a and at least one second tab 221b, wherein the first tab 221a and the second tab 221b have opposite polarities. For example, the first tab 221a can be a positive tab, and the second tab 221b can be a negative tab. The positive electrode terminal is used for electrical connection to the positive electrode tab of the electrode assembly 22, and the negative electrode terminal is used for electrical connection to the negative electrode tab of the electrode assembly 22. The positive electrode terminal and the positive electrode tab can be directly connected or indirectly connected, as can the negative electrode terminal and the negative electrode tab. For example, the positive electrode terminal can be electrically connected to the positive electrode tab via a connecting member 23, and the negative electrode terminal can be electrically connected to the negative electrode tab via a connecting member 23.

[0135] like Figure 5As shown, a sealing component 26 can be provided between the electrode terminal 214 and the end cap 212, thereby isolating the environment inside the battery cell 20 from the gap between the electrode terminal 214 and the end cap 212, so as to prevent the contents of the battery cell 20 from seeping into the gap between the electrode terminal 214 and the end cap 212 and causing the electrode terminal 214 and the end cap 212 to short-circuit.

[0136] The sealing component 26 can be an elastic component, such as a polyurethane seal, a silicone seal, or a rubber seal. This application embodiment does not limit this.

[0137] A support member 216 may also be provided between the end cap 212 and the electrode assembly 22. The support member 216 may be made of plastic and covers the side of the end cap 212 facing the electrode assembly 22, thereby improving the impact resistance of the end cap.

[0138] It should be understood that each electrode terminal 214 in this embodiment can be disposed on any wall, and multiple electrode terminals 214 can be disposed on the same wall or different walls of the battery cell 20. For example, as Figure 3 As shown, each battery cell 20 includes two electrode terminals 214, which are located on the same wall. For example, both electrode terminals 214 can be located on the end cap 212.

[0139] For example, again taking the case where each battery cell 20 includes two electrode terminals 214, and these two electrode terminals 214 are located on the same wall, unlike... Figure 3 As shown, the two electrode terminals 214 can also be located in the housing 211.

[0140] An electrolyte injection hole 215 can also be provided on the outer casing 21, through which electrolyte can be injected into the battery cell 20 and then sealed by a sealing component.

[0141] The battery cell 20 can also be provided with a bottom support plate 24, which can support the electrode assembly 22 to avoid collision and compression between the electrode assembly 22 and the bottom wall of the housing 211.

[0142] The positive electrode tab 221a can be formed by stacking the portion of the positive electrode sheet that is not coated with the positive active material, and the negative electrode tab 221b can be formed by stacking the portion of the negative electrode sheet that is not coated with the negative active material.

[0143] The housing 21 may be provided with a pressure relief mechanism 213. The pressure relief mechanism 213 can release pressure inside the battery cell 20. For example, it may be actuated to release internal pressure or temperature when the internal pressure or temperature of the battery cell 20 reaches a predetermined threshold. When the internal pressure or temperature of the battery cell 20 reaches the predetermined threshold, the pressure relief mechanism 213 actuates or a weak structure within the pressure relief mechanism 213 is broken, thereby forming an opening or channel for internal pressure or temperature release. This threshold design varies depending on design requirements. The threshold may depend on the materials of one or more of the positive electrode, negative electrode, electrolyte, and separator in the battery cell 20.

[0144] The term "actuation" as used in this application refers to the pressure relief mechanism 213 being activated or undergoing a certain state, thereby releasing the internal pressure and temperature of the battery cell 20. The actions of the pressure relief mechanism 213 may include, but are not limited to: movement of components within the pressure relief mechanism 213 to form an exhaust channel, rupture, breakage, tearing, or opening of at least a portion of the pressure relief mechanism 213, etc. When the pressure relief mechanism 213 is actuated, the high-temperature, high-pressure substances inside the battery cell 20 are discharged outwards from the actuated portion as exhaust materials. This method enables pressure and temperature relief of the battery cell under controllable pressure or temperature, thereby preventing potentially more serious accidents.

[0145] The emissions from the battery cell 20 mentioned in this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, etc.

[0146] This application does not limit the shape of the pressure relief mechanism 213. For example, the pressure relief mechanism 213 can be a racetrack shape composed of two line segments and two semicircular arcs. The above is only an exemplary description and should not constitute a limitation on the pressure relief mechanism 213. The pressure relief mechanism 213 can also be designed into other shapes as needed.

[0147] like Figure 5 As shown, the pressure relief mechanism 213 may also include a protective structure 2131 to protect the pressure relief mechanism 213 from external interference. For example, the protective structure 2131 may be a protective patch, which can be attached to the surface of the housing 211. If the housing 211 has a groove, it can also be attached to the bottom wall of the groove to cover other structures located on the bottom wall of the groove. This embodiment of the application does not limit this.

[0148] The following is combined Figures 6 to 10 This application describes a battery cell provided in one embodiment.

[0149] in, Figure 6 This is a top view of a battery cell provided in an embodiment of this application. Figure 7 yes Figure 6 AA cross-sectional view of a single battery cell. Figure 8 yes Figure 6 CC cross-section view. Figure 9 This is a schematic diagram of the electrode terminals in a battery cell provided in an embodiment of this application. Figure 10 This is a schematic diagram of the electrode terminals in a battery cell provided in an embodiment of this application.

[0150] The battery cell 20 may include a housing 21 forming a receiving cavity. The housing 21 includes a first wall 210 with a first through hole 2121. The battery cell 20 may also include an electrode assembly 22 housed within the receiving cavity. A first electrode terminal 214a is included, with its projection onto the first wall 210 covering the first through hole 2121. The first electrode terminal 214a includes a main body portion 2142 and a peripheral portion 2141 connected to the main body portion 2142. The peripheral portion 2141 at least partially overlaps with the first wall 210 along the thickness direction. A first groove 2144 is provided on the side of the peripheral portion 2141 facing the first wall 210, and the first groove 2144 at least partially overlaps with the first wall 210 along the thickness direction.

[0151] For example, the first wall 210 may be an end cap 212 of the battery cell 20, which covers the opening of the receiving cavity enclosed by the housing 211. The first wall may also be other walls of the battery cell 20, and the embodiments of this application are not limited thereto.

[0152] The first electrode terminal 214a can be either a negative electrode terminal or a positive electrode terminal.

[0153] The figure shows the first electrode terminal as a cylinder as an example, but the shape of the first electrode terminal 214a is not limited in the embodiments of this application. For example, the first electrode terminal 214a can also be square.

[0154] The figure shows, for example, a protruding structure provided on the side of the first electrode terminal 214a facing the outside of the battery cell 20. However, the embodiments of this application are not limited thereto, and the shape of the first electrode terminal 214 can be set as needed.

[0155] The first electrode terminal 214a can be made entirely of the same material, or it can be made of a composite of different materials, for example... Figure 8 The first electrode terminal 214a shown can be a copper-aluminum composite electrode terminal, wherein the side facing the outside of the battery cell 20 is aluminum, and the side facing the inside of the battery cell 20 is copper. The first electrode terminal 214a can also be made of other materials and in different composite ways, which are not limited to this application.

[0156] The first electrode terminal 214a covering the side of the first through hole 2121 away from the electrode assembly 22 can mean that the first through hole 2121 connects the inside and outside of the battery cell 20, and the first electrode terminal 214a covers the first through hole 2121 from the outside of the battery cell 20.

[0157] The side of the first electrode terminal 214a facing the electrode assembly 22 can refer to the surface of the first electrode terminal 214a facing the inside of the battery cell 20.

[0158] The peripheral portion 2141 can be a structure continuously arranged around the main body portion 2142, or it can be a structure discontinuously arranged around the main body portion 2142. This application embodiment does not limit this.

[0159] The fact that the peripheral portion 2141 at least partially overlaps with the first wall 210 in the thickness direction can be understood as the peripheral portion 2141 and the first wall 210 being stacked in the thickness direction.

[0160] The fact that the peripheral portion 2141 is at least partially stacked with the first wall 210 in the thickness direction can be understood as the peripheral portion 2141 being stacked with the portion of the first wall 210 outside the first through hole 2121.

[0161] For example, such as Figure 8 As shown, the orthographic projection of the first electrode terminal 214a along the thickness direction of the first wall 210 can cover the orthographic projection of the first through hole 2121 along the thickness direction of the first wall 210.

[0162] When the first electrode terminal 214a covers the side of the first through hole 2121 away from the electrode assembly 22, there is a stacked portion between the edge of the first through hole 2121 of the first wall 210 and the side of the first electrode terminal 214a facing the electrode assembly 22. This stacked portion is prone to short circuit, which can cause the end cap or even the entire casing to become charged, resulting in casing corrosion and affecting the stability of the battery.

[0163] In this embodiment, the first electrode terminal 214a covers the side of the first through hole 2121 away from the electrode assembly 22, and the portion of the first electrode terminal 214a opposite to the first wall 210 is provided with a first groove 2144, which reduces the possibility of short-circuiting between the side of the first wall 210 away from the electrode assembly 22 and the side of the first electrode terminal 214a facing the electrode assembly 22 at the periphery 2141, thereby improving the stability of the battery cell 20 in use.

[0164] In some possible embodiments, such as Figure 10 As shown, the battery cell 20 also includes an insulating component 2143, which is disposed between the first electrode terminal 214a and the first wall 210, and the insulating component 2143 is at least partially disposed in the first groove 2144.

[0165] Figure 9 The electrode terminals in the middle are not covered with insulating components 2143. Figure 10 The electrode terminals are covered with insulating components 2143, in which Figure 9 (a) in the figure is a top view of the electrode terminals. Figure 9 (b) in the figure is a side view of the electrode terminals. Figure 9 (c) in the figure is a bottom view of the electrode terminals. Figure 10 (a) in the figure is a top view of the electrode terminals. Figure 10 (b) is a cross-sectional view of the electrode terminal EE. Figure 10 (c) in the figure is a bottom view of the electrode terminal. In the figure, the upper part of the electrode terminal is shown as an example with a stepped structure, but the embodiments of this application are not limited thereto, and the stepped structure can be designed as needed.

[0166] In addition to the portions that are arranged opposite each other along the thickness direction of the first wall 210, the first electrode terminal 214a and the first wall 210 also have portions that are arranged opposite each other along the thickness direction perpendicular to the first wall 210. The insulating member 2143 can be disposed in the area between these portions to insulate the first electrode terminal 214a from the end cap 212.

[0167] The insulating component 2143 can be thermosetting plastic, rubber, etc., and this application does not limit the material of the insulating component 2143.

[0168] The insulating component 2143 can have various names, such as plastic coating, etc. The name of the insulating component 2143 is not limited in this application embodiment.

[0169] In the embodiments provided in this application, the insulating component 2143 is at least partially disposed in the first groove 2144, which further increases the creepage distance between the first electrode terminal 214a and the side of the first wall 210 away from the electrode assembly 22, thereby further reducing the possibility of short circuit between the first electrode terminal 214a and the first wall 210 and improving the stability of the battery cell 20 in use.

[0170] In some possible embodiments, the battery cell may further include a sealing member 26, the outer edge of the sealing member 26 projecting toward the first wall 210 surrounding the first through hole 2121, and the inner edge of the sealing member 26 projecting toward the first wall 210 within the range of the first through hole 2121.

[0171] The sealing component 26 can isolate the gap between the inside of the battery cell 20 and the first electrode terminal 214a and the first wall 210. In particular, it encapsulates the electrolyte inside the battery cell 20, so that the gap formed between the first wall 210 and the first electrode terminal 214a does not have the conditions for dendrite precipitation, reducing the possibility that the first electrode terminal 214a and the first wall 210 will overlap through dendrites.

[0172] In the embodiments of this application, dendrites can refer to dendritic spreading crystals, which can be formed by the crystallization of ions in the electrolyte or permeate. The crystallizing ions can be, for example, copper ions, or other ions. This application does not limit this.

[0173] In this embodiment, the sealing member 26 surrounds the first through hole 2121 with the outer edge of the orthographic projection of the first wall 210, and the inner edge of the sealing member 26 facing the orthographic projection of the first wall 210 is within the range of the first through hole 2121. The sealing member 26 can cover the portion of the periphery 2141 facing the first wall 210, thereby further reducing the possibility of short circuit between the first electrode terminal 214a and the first wall 210.

[0174] Figure 11 A schematic diagram of the electrode terminals in a battery cell provided in an embodiment of this application is shown.

[0175] In some possible embodiments, such as Figure 11 As shown, a protruding structure 2122 is provided on the side of the first wall 210 facing the first electrode terminal 214a. The protruding structure 2122 surrounds the first through hole 2121. The sealing member 26 is disposed between the protruding structure 2122 and the peripheral portion 2141, so that the protruding structure 2122 presses the sealing member 26 onto the first electrode terminal 214a.

[0176] For example, the shape of the cross section of the protrusion structure 2122 cut by the plane perpendicular to the first wall 210 can be rectangular, but the embodiments of this application are not limited thereto. For example, the shape of the cross section of the protrusion structure 2122 cut by the plane perpendicular to the first wall 210 can also be semi-circular.

[0177] In some possible embodiments, the distance d1 between the inner and outer edges of the protrusion structure 2122 in the orthographic projection of the first wall 210 in the thickness direction is greater than 0.3 mm.

[0178] In this embodiment, the distance d1 between the inner and outer edges of the protruding structure 2122 in the orthogonal projection of the first wall 210 in the thickness direction is greater than 0.3 mm, which allows the sealing component 26 to be more firmly pressed against the first electrode terminal 214a by the protruding structure 2122, thereby providing a good sealing effect and reducing the leakage of electrolyte inside the battery cell 20.

[0179] Furthermore, the distance d1 between the inner and outer edges of the protruding structure 2122 in the orthographic projection of the first wall 210 in the thickness direction can be greater than 0.35 mm. When d1 is within this range, the protruding structure 2122 presses against the sealing member 26 more firmly, and can further improve the stability of the seal in the event that the sealing member 26 becomes loose.

[0180] In some embodiments, the distance d1 between the inner and outer edges of the protrusion structure 2122 in the orthographic projection of the first wall 210 in the thickness direction can be set to other values. For example, the distance d1 can be any one of the following values ​​or between any two of the following values: 0.3mm, 0.32mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm.

[0181] In some possible embodiments, the outer edge of the sealing member 26, which is projected toward the first wall 210, surrounds the inner edge of the first groove 2144, which is projected toward the first wall 210.

[0182] A gap is formed between the first wall 210 and the peripheral portion 2141 along the thickness direction of the first wall 210, and the gap does not include the space of the first through hole 2121 portion.

[0183] The portion of the sealing component 26 located outside the first through hole 2121 can refer to the portion of the sealing component 26 whose orthographic projection along the thickness direction of the first wall 210 is located outside the orthographic projection of the first through hole 2121 along the thickness direction of the first wall 210.

[0184] In this embodiment, the volume of the portion of the sealing member 26 located outside the first through hole 2121 is greater than or equal to the volume of the gap between the peripheral portion 2141 and the first wall 210. After compression, the sealing member 26 can cover the portion of the peripheral portion 2141 that is opposite to the first wall 210, thereby covering the space between the first wall 210 and the peripheral portion 2141 where dendrites can be formed, reducing the possibility of short circuit between the first wall 210 and the first electrode terminal 214a.

[0185] refer to Figure 11 In some possible embodiments, the first groove 2144 is an annular groove, the first through hole 2121 is a circular through hole, the distance between the periphery 2141 and the first wall 210 is H1, the inner diameter of the first groove 2144 projected onto the first wall 210 is R1, the radius of the first through hole 2121 is R2, and the volume V1 of the portion of the sealing member 26 located outside the first through hole 2121 satisfies V1≥H1×π(R1 / 2) 2 -R22, where π is the value of a circle.

[0186] In this embodiment of the application, by designing and calculating the volume of the sealing component 26, a reference can be provided for the selection of the sealing component 26 before assembly, thereby reducing sealing problems after assembly or product defects caused by insufficient compression margin of the sealing component 26 during use.

[0187] In some possible embodiments, the volume V1 of the portion of the sealing member 26 located outside the first through hole 2121 satisfies V1≥(H1+H2)×π(R1) 2 -R2 2 ), where π is the ratio of a circle to a circle, and H2 satisfies 0.01mm < H2 < 0.3mm.

[0188] In this embodiment, by incorporating a springback allowance into the design of the sealing component 26, the sealing component 26 can still perform an effective sealing function even if it springs back during use, thereby improving the stability of the battery cell 20.

[0189] Furthermore, H2 can also satisfy 0.02mm < H2 < 0.25mm. When H2 is within this range, the sealing component 26 can have a certain springback margin, and at the same time, it will not take up too much height space.

[0190] In some embodiments of this application, the value of H2 can also be set to other values. For example, the value of H2 can be any one of the following values ​​or between any two of the following values: 0.01mm, 0.02mm, 0.03mm, 0.04mm, 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.1mm, 0.12mm, 0.15mm, 0.18mm, 0.2mm, 0.25mm, 0.3mm.

[0191] Figure 12 A schematic diagram of the electrode terminals in a battery cell provided in an embodiment of this application is shown.

[0192] like Figure 12 As shown, in some possible embodiments, a second groove 2123 is provided on the side of the end cap facing the first electrode terminal 214a, the second groove 2123 surrounds the first through hole 2121, and the sealing member 26 is at least partially accommodated in the second groove 2123.

[0193] In this embodiment, a second groove 2123 is provided on the side of the first wall 210 facing the first electrode terminal 214a to accommodate part of the sealing component 26. The sealing component 26 can undergo volume flow during deformation, thereby reducing the compression restriction of the sealing component 26 caused by overpressure, and thus reducing the problem of reduced airtightness of the battery cell 20 caused by the aging process of the sealing component 26.

[0194] In some possible embodiments, the second groove 2123 is further away from the first through hole 2121 relative to the protrusion 2122.

[0195] refer to Figure 13 And further reference Figure 14 ,in, Figure 13 A schematic diagram of the electrode terminals in a battery cell 20 provided in an embodiment of this application is shown; Figure 14 A schematic diagram of the electrode terminals in a battery cell 20 provided in an embodiment of this application is shown. Figure 13 (a) in the figure is a top view of the electrode terminals. Figure 13 (b) in the figure is a side view of the electrode terminals. Figure 13 (c) in the figure is a bottom view of the electrode terminals.

[0196] Figure 14 (a) in the figure is a top view of the electrode terminals. Figure 14 (b) in the figure is a cross-sectional view of the electrode terminal FF. Figure 14 (c) in the figure is a bottom view of the electrode terminals.

[0197] In some possible embodiments, the peripheral portion 2141 is provided with a limiting portion 2145, which cooperates with the insulating member 2143 to limit the circumferential movement of the first electrode terminal 214a.

[0198] The limiting part 2145 can be a protrusion structure, a slot structure, etc., and the embodiments of this application do not limit it.

[0199] For example, such as Figure 13 and Figure 14 As shown, the limiting portion 2145 includes a notch disposed circumferentially along the first electrode terminal 214a, and the insulating member 2143 at least partially fills the notch to restrict the movement of the first electrode terminal 214a circumferentially.

[0200] In some possible embodiments, the first electrode terminal 214a is a negative electrode terminal.

[0201] When the negative electrode terminal is short-circuited to the first wall 210, the first wall 210 and even the casing 211 will become negatively charged, making them more susceptible to corrosion. When the casing 211 is made of aluminum, the aluminum can also form a lithium-aluminum alloy with the lithium ions in the lithium battery, leading to corrosion and leakage of the casing 211. Therefore, when the first electrode terminal 214a is the negative electrode terminal, reducing the likelihood of a short circuit between the first wall 210 and the first electrode terminal 214a can more effectively suppress casing corrosion.

[0202] In some possible embodiments, the first wall 210 is also provided with a liquid injection hole 215, which is located at the end of the first wall 210 away from the first electrode terminal 214a.

[0203] According to some embodiments of this application, this application also provides a battery device including a battery cell described in any of the above embodiments.

[0204] According to some embodiments of this application, this application also provides an electrical device, including the battery device described in any of the above embodiments, and the battery device is used to provide electrical energy to the electrical device.

[0205] The electrical device can be any of the aforementioned devices or systems that utilize battery devices.

[0206] According to some embodiments of this application, see Figures 5 to 11 This application provides a battery cell 20. The end cap 212 of the battery cell 20 is provided with a first through hole 2121 and a liquid injection hole 215. The liquid injection hole 215 is located at the end of the end cap 212 away from the first through hole 2121. A first electrode terminal 214a covers the first through hole 2121 from the outside of the battery cell 20. The first electrode terminal 214a includes a main body portion 2142 and a peripheral portion 2141. The peripheral portion 2141 is connected to the main body portion 2142. The peripheral portion 2141 at least partially overlaps with the end cap 212 in the thickness direction. A first groove 2144 is provided on the side of the peripheral portion 2141 facing the end cap 212. The first groove 2144 at least partially overlaps with the end cap 212 in the thickness direction, so that the first groove 2144 is far away from the end cap 212 relative to the other part of the peripheral portion 2141, thereby reducing the possibility of overlap between the first electrode terminal 214a and the end cap 212. The insulating component 2143 covers the circumference of the first electrode terminal 214a and further covers the first groove 2144 to increase the creepage distance between the end cap 212 and the first electrode terminal 214a and reduce the exposed area between the first electrode terminal 214a and the end cap 212. Further, the end cap 212 is provided with a protruding structure 2122 surrounding the first through hole 2121. A sealing component 26 is disposed between the protruding structure 2122 and the circumference 2141, such that the protruding structure 2122 presses the sealing component 26 onto the first electrode terminal 214a. The volume of the sealing component 26 outside the first through hole 2121 is greater than or equal to the volume of the space between the circumference 2141 and the end cap 212 along the thickness direction of the end cap 212, thereby allowing the compressed sealing component 26 to cover the circumference 2141, further reducing the exposed area between the end cap 212 and the first electrode terminal 214a.

[0207] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized by, The battery cell comprises: a housing (21) forming a receiving cavity, the housing (21) comprising a first wall (210) provided with a first through hole (2121); an electrode assembly (22) received in the receiving cavity; a first electrode terminal (214a) whose orthographic projection towards the first wall (210) covers the first through hole (2121), the first electrode terminal (214a) comprising a main body portion (2142) and a peripheral portion (2141) connected to the main body portion (2142), the peripheral portion (2141) at least partially overlapping the first wall (210) in the thickness direction; wherein the peripheral portion (2141) is provided on the side thereof facing the first wall (210) with a first groove (2144) at least partially overlapping the first wall (210) in the thickness direction.

2. The battery cell of claim 1, wherein, The battery cell further comprises: an insulating member (2143) provided between the first electrode terminal (214a) and the first wall (210), wherein the insulating member (2143) is at least partially provided in the first groove (2144).

3. The battery cell of claim 1, wherein, The battery cell further comprises: a sealing member (26) whose orthographic projection towards the first wall (210) surrounds the outer edge of the first through hole (2121), and whose orthographic projection towards the first wall (210) has an inner edge within the range of the first through hole (2121).

4. The battery cell of claim 3, wherein, The first wall (210) is provided on the side thereof facing the first electrode terminal (214a) with a raised structure (2122) surrounding the first through hole (2121), and the sealing member (26) is provided between the raised structure (2122) and the peripheral portion (2141) so that the raised structure (2122) presses the sealing member (26) onto the first electrode terminal (214a).

5. The battery cell of claim 4, wherein, The spacing between the inner edge and the outer edge of the orthographic projection of the raised structure (2122) towards the first wall (210) is greater than 0.3 mm.

6. The battery cell of claim 3, wherein, The sealing member (26) surrounds the inner edge of the orthographic projection of the first groove (2144) towards the first wall (210) with the outer edge of the orthographic projection of the first groove (2144) towards the first wall (210).

7. The battery cell of claim 6, wherein, The first recess (2144) is a circular annular recess, the first through-hole (2121) is a circular through-hole, the spacing between the peripheral portion (2141) and the first wall (210) is , the inner diameter of the orthographic projection of the first recess (2144) toward the first wall (210) is , the radius of the first through-hole (2121) is , the volume outside the first through-hole (2121) where the sealing member (26) is located is satisfies , wherein is the ratio of the circumference of a circle to its diameter.

8. The battery cell of claim 6, wherein, The first groove (2144) is an annular groove, the first through hole (2121) is a circular through hole, and the distance between the peripheral portion (2141) and the first wall (210) is... The inner diameter of the first groove (2144) projected onto the first wall (210) is... The radius of the first through hole (2121) is The volume of the sealing component (26) located outside the first through hole (2121) satisfy Where π is the ratio of a circle's diameter to its circumference. Satisfying 0.01mm < <0.3mm.

9. The battery cell of claim 3, wherein, The first wall (210) is provided on the side thereof facing the first electrode terminal (214a) with a second groove (2123) surrounding the first through hole (2121), and the sealing member (26) is at least partially received in the second groove (2123).

10. The battery cell of claim 9, wherein, The first wall (210) is provided on the side thereof facing the first electrode terminal (214a) with a raised structure (2122) surrounding the first through hole (2121), and the second groove (2123) is farther away from the first through hole (2121) relative to the raised structure (2122).

11. The battery cell of claim 2, wherein, The peripheral portion (2141) is provided with a limiting portion (2145) cooperating with the insulating member (2143) to limit the movement of the first electrode terminal (214a) in the circumferential direction.

12. The battery cell of claim 11, wherein, The limiting portion (2145) comprises a notch arranged in the circumferential direction of the first electrode terminal (214a), and the insulating member (2143) at least partially fills the notch to limit the movement of the first electrode terminal (214a) in the circumferential direction.

13. The battery cell of any one of claims 1 to 12, wherein, The first electrode terminal (214a) is a negative electrode terminal.

14. The battery cell of claim 13, wherein, The first wall (210) is further provided with a liquid injection hole (215) arranged at an end of the first wall (210) away from the first electrode terminal (214a).

15. An end cap assembly characterized by, The end cover assembly is used for a battery monomer, the battery monomer comprising a shell (211) and an electrode assembly (22), the shell (211) being a hollow structure with an opening, and the electrode assembly (22) being accommodated in the shell (211); The end cover assembly comprises: an end cover (212) covering the opening, the end cover (212) having a first through hole (2121); a first electrode terminal (214a) covering a side of the first through hole (2121) away from the electrode assembly (22), the first electrode terminal (214a) comprising a main body portion (2142) and a peripheral portion (2141), the peripheral portion (2141) being connected to the main body portion (2142), and the peripheral portion (2141) at least partially overlapping the end cover (212) in the thickness direction; wherein a first groove (2144) is arranged on a side of the peripheral portion (2141) facing the end cover (212), and the first groove (2144) at least partially overlaps the end cover (212) in the thickness direction.

16. A battery device characterized by comprising: comprise: the battery monomer of any one of claims 1 to 14.

17. An electrical device, comprising: comprise: the battery monomer of any one of claims 1 to 14, or the battery device of claim 16, wherein the battery monomer or the battery device is used to provide electric energy.

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