Battery monomer, battery and electric device

Abstract

The utility model provides a battery monomer, a battery and a power utilization device. The battery monomer comprises a shell, an electrode assembly and an electrode terminal, a containing cavity is formed in the shell, the shell comprises a wall part, the wall part is provided with a first concave part and an electrode leading-out hole, the surface, facing the containing cavity, of the first concave part relative to the wall part is concave, and the electrode leading-out hole penetrates through the bottom wall of the first concave part in the thickness direction of the wall part. The electrode assembly is arranged in the containing cavity and comprises a tab, the electrode terminal is arranged on the wall part and electrically connected to the tab, and at least part of the electrode terminal located in the containing cavity is contained in the first concave part. According to the invention, the energy density of the battery monomer can be effectively improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery cell, a battery and an electrical device. Background Art

[0002] With the development of new energy technology, batteries are used more and more widely, for example, in mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes and electric tools, etc.

[0003] The energy density of a battery cell refers to the amount of electrical energy that can be released per unit volume or unit mass of the battery cell, which has an important impact on the economic benefits of the battery. Therefore, how to effectively improve the energy density of a battery cell is an urgent problem to be solved in battery technology. Utility Model Content

[0004] In view of the above problems, the present application provides a battery cell, a battery and an electrical device, which can effectively improve the energy density of the battery cell.

[0005] In the first aspect, the embodiment of the present application provides a battery cell, the battery cell includes a shell, an electrode assembly and an electrode terminal, the shell is provided with a receiving cavity inside, the shell includes a wall portion, the wall portion has a first recess and an electrode lead-out hole, the first recess is recessed relative to the surface of the wall portion facing the receiving cavity, and the electrode lead-out hole penetrates the bottom wall of the first recess along the thickness direction of the wall portion. The electrode assembly is disposed in the receiving cavity and includes a tab, the electrode terminal is disposed in the wall portion and electrically connected to the tab, and at least a portion of the electrode terminal located in the receiving cavity is accommodated in the first recess.

[0006] The first recess of the above technical solution can be used to accommodate the electrode terminal to reduce the occupancy rate of the electrode terminal to the internal space of the battery cell, so that more space can be freed up inside the battery cell to arrange the electrode assembly, thereby effectively improving the energy density of the battery cell.

[0007] In some embodiments of the first aspect, the wall portion further has a second recessed portion, the second recessed portion is recessed relative to a surface of the wall portion on a side facing away from the accommodating cavity, and a portion of the electrode terminal is accommodated in the second recessed portion.

[0008] The second recess of the above technical solution can be used to accommodate the portion of the electrode terminal located outside the shell to reduce the occupancy rate of the electrode terminal to the external space of the battery cell, which is beneficial to reducing the overall volume of the battery cell, thereby further improving the energy density of the battery cell.

[0009] In some embodiments of the first aspect, a projection of the second recess in the thickness direction of the wall portion surrounds a projection of the first recess in the thickness direction.

[0010] The second recess and the first recess can be staggered with each other in the thickness direction of the wall to avoid interference between the first recess and the second recess to a certain extent. This not only reduces the difficulty of setting the first recess and the second recess, but also reduces the risk of fracture due to low structural strength caused by the local thickness of the wall being too small, thereby improving the reliability of the battery cell.

[0011] In some embodiments of the first aspect, the wall portion further has a convex portion, which protrudes from a surface of the wall portion facing away from the accommodating cavity, and a position of the convex portion corresponds to a position of the first concave portion.

[0012] The above technical solution, by arranging a convex portion at the position of the first concave portion, is conducive to increasing the thickness of the wall portion at the position of the first concave portion, thereby improving the overall structural strength of the wall portion, reducing the risk of fracture due to low structural strength caused by the local thickness of the wall portion being too small, and improving the reliability of the battery cell.

[0013] In some embodiments of the first aspect, the electrode terminal has a third recessed portion, the third recessed portion is recessed relative to a surface of the electrode terminal facing the wall portion, and at least a portion of the protrusion is accommodated in the third recessed portion.

[0014] The third recessed portion of the above technical solution can be used to accommodate the protruding portion to reduce the size of the battery cell in the thickness direction of the wall portion, which is beneficial to reducing the overall volume of the battery cell, thereby further improving the energy density of the battery cell.

[0015] In some embodiments of the first aspect, the battery cell further includes a sealing member, wherein at least a portion of the sealing member surrounds the electrode lead-out hole in a thickness direction and is sandwiched between the electrode terminal and a bottom wall of the first recess.

[0016] The electrode lead-out hole of the above technical solution can facilitate the connection of the electrode terminal with the busbar and other conductive elements, thereby improving the convenience of using the battery cell; the seal can form a seal between the electrode terminal and the bottom wall of the first recess, thereby reducing the risk of external water vapor or impurities entering the battery cell through the electrode lead-out hole and damaging the battery cell. In addition, the seal can be accommodated in the first recess, which can reduce the occupation of the seal in the internal space of the battery cell, thereby effectively improving the energy density of the battery cell.

[0017] In some embodiments of the first aspect, the electrode terminal is inserted into the electrode lead-out hole, the electrode terminal includes a pole and a terminal plate, the pole includes a connecting portion and a limiting portion, the connecting portion connects the limiting portion and the terminal plate, and the bottom wall of the first recess is clamped between the limiting portion and the terminal plate.

[0018] The above technical solution can further improve the connection firmness between the electrode terminal and the wall portion by clamping the bottom wall of the first recess between the limiting portion and the terminal plate, thereby effectively improving the reliability of the battery cell.

[0019] In some embodiments of the first aspect, a through hole is formed in the terminal board, and the pole passes through the electrode lead-out hole and extends into the through hole to be connected with the terminal board.

[0020] In the above technical solution, the pole extends into the through hole and is connected to the terminal board, which can increase the contact area between the pole and the terminal board, thereby facilitating the connection firmness between the pole and the terminal board, so as to further improve the overall reliability of the electrode terminal.

[0021] In some embodiments of the first aspect, the seal includes a first part and a second part that are connected, the first part is clamped between the inner wall of the electrode lead-out hole and the connecting part, and the second part is clamped between the limiting part and the bottom wall of the first recess.

[0022] The seal of the above technical solution can not only seal between the limiting portion and the bottom wall of the first recess, but also seal between the inner wall of the electrode lead-out hole and the connecting portion, so that the sealing path of the seal can be increased, thereby further improving the sealing effect of the seal.

[0023] In some embodiments of the first aspect, the seal further includes a third portion, the first portion is connected between the second portion and the third portion, and the third portion is sandwiched between the terminal board and a surface of the wall portion facing away from the accommodating cavity.

[0024] The seal of the above technical solution can further seal between the terminal board and the surface of the wall portion facing away from the accommodating cavity, so that the sealing path of the seal can be further increased, thereby further improving the sealing effect of the seal.

[0025] In some embodiments of the first aspect, a first dimension H1 of the wall portion in its own thickness direction and a second dimension H2 of the first recessed portion in the thickness direction satisfy the relationship: 0<H2 / H1≤0.5.

[0026] The above technical solution sets the first dimension H1 of the wall in its own thickness direction and the second dimension H2 of the first recess in the thickness direction to satisfy the above relationship, thereby reducing the occupancy rate of the electrode terminal to the internal space of the battery cell, thereby improving the energy density of the battery cell and taking into account the overall structural consistency of the wall.

[0027] In some embodiments of the first aspect, the electrode terminal located in the accommodating cavity has a third dimension H3 in the thickness direction, and the third dimension H3 satisfies the relationship: 1.5 mm≤H3≤5 mm.

[0028] The above technical solution sets the third dimension H3 of the electrode terminal in the accommodating cavity in the thickness direction within the above range, which can reduce the occupancy rate of the electrode terminal to the internal space of the battery cell while ensuring the structural strength and connection firmness of the electrode terminal, thereby taking into account the energy density and reliability of the battery cell.

[0029] In some embodiments of the first aspect, the housing includes a shell and an end cover, the shell has an opening and a receiving cavity, the end cover is used to cover the opening, and the end cover is configured as a wall portion.

[0030] In a second aspect, the present application provides a battery, which includes a battery cell provided by any embodiment of the first aspect.

[0031] In a third aspect, the present application provides an electrical device, comprising a battery cell provided by any embodiment of the first aspect, wherein the battery cell is used to provide electrical energy.

[0032] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0034] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0035] Figure 2 A schematic diagram of an exploded structure of a battery provided in some embodiments of the present application;

[0036] Figure 3 A schematic diagram of the structure of a battery module provided in some embodiments of the present application;

[0037] Figure 4 A schematic diagram of an exploded structure of a battery cell provided in some embodiments of the present application;

[0038] Figure 5 A schematic diagram of a top view structure of a battery cell provided in some embodiments of the present application;

[0039] Figure 6 for Figure 5 Schematic diagram of the cross-section structure along AA;

[0040] Figure 7 A schematic diagram of a top view of another battery cell provided in some embodiments of the present application;

[0041] Figure 8 for Figure 7 Schematic diagram of the cross-sectional structure along BB.

[0042] The reference numerals in the specific implementation manner are as follows:

[0043] 1. Vehicle; 2. Battery; 3. Controller; 4. Motor; 5. Box; 5a. First box portion; 5b. Second box portion; 5c. Accommodation space; 6. Battery module; 7. Battery cell;

[0044] 10. Shell; 10a. Shell; 10b. End cover; 11. Accommodating cavity; 12. Wall; 121. First recess; 122. Second recess; 123. Protrusion; 124. Electrode lead-out hole; 20. Electrode assembly; 30. Electrode terminal; 31. Third recess; 32. Pole; 321. Connecting portion; 322. Limiting portion; 33. Terminal board; 331. Through hole; 40. Sealing member; 41. First part; 42. Second part; 43. Third part; 50. First insulating member; 60. Second insulating member; X. Thickness direction. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0046] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by technicians in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0047] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0048] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0049] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0050] In the embodiments of the present application, the same reference numerals represent 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 the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0051] The term "plurality" used in the present application refers to two or more (including two).

[0052] In the present application, the term "parallel" includes not only the absolutely parallel situation, but also the roughly parallel situation conventionally recognized in engineering; meanwhile, "vertical" includes not only the absolutely vertical situation, but also the roughly vertical situation conventionally recognized in engineering.

[0053] In the embodiment of the present application, the battery cell may be a secondary battery cell, which refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0054] The battery cells can be lithium-ion battery cells, sodium-ion battery cells, sodium-lithium-ion battery cells, lithium metal battery cells, sodium metal battery cells, lithium-sulfur battery cells, magnesium-ion battery cells, nickel-hydrogen battery cells, nickel-cadmium battery cells, lead-acid battery cells, etc., which are not limited in the embodiments of the present application.

[0055] A battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode and a negative electrode. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are inserted and removed back and forth between the positive electrode and the negative electrode.

[0056] In some embodiments, the electrode assembly further includes a separator, which is disposed between the positive electrode and the negative electrode to prevent the positive and negative electrodes from short-circuiting while allowing active ions to pass through.

[0057] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet may include a positive electrode current collector and a positive electrode active material layer disposed on at least one surface of the positive electrode current collector.

[0058] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material layer is disposed on any one or both of the two facing surfaces of the positive electrode current collector.

[0059] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, stainless steel, copper, aluminum, nickel, silver-surface-treated aluminum, silver-surface-treated stainless steel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0060] As an example, the positive electrode active material layer includes a positive electrode active material. The positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials for batteries can also be used. These positive electrode active materials can be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates may include, but are not limited to, lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and at least one of a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 )、LiNi 0.5 Co0.2 Mn 0.3 O2 (also referred to as NCM 523 )、LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 )、LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM 622 )、LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.80 Co 0.15 Al 0.05 O2) and its modified compounds, etc.

[0061] In some embodiments, the positive electrode may be carbon foam or metal foam. The metal foam may be nickel foam, copper foam, aluminum foam or alloy foam. When the metal foam is used as the positive electrode, the positive electrode active material may not be provided on the surface of the metal foam, but the positive electrode active material may also be provided. As an example, lithium source material, potassium metal or sodium metal may be filled or / and deposited in the metal foam, and the lithium source material is lithium metal and / or lithium-rich material.

[0062] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector.

[0063] As an example, the negative electrode current collector may be a metal foil, a foamed metal, a foamed carbon or a composite current collector. For example, as a metal foil, stainless steel, copper, aluminum, nickel, silver-surface-treated aluminum, silver-surface-treated stainless steel, a carbon electrode, carbon, nickel or titanium, etc. may be used. The foamed metal may be a foamed nickel, a foamed copper, a foamed aluminum or a foamed alloy, etc. The composite current collector may include a polymer material base and a metal layer. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0064] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0065] In some embodiments, the negative electrode may be foamed carbon or foamed metal. The foamed metal may be foamed nickel, foamed copper, foamed aluminum or foamed alloy, etc. When the foamed metal is used as the negative electrode sheet, the surface of the foamed metal may not be provided with a negative electrode active material, but of course, a negative electrode active material may also be provided.

[0066] As an example, a lithium source material, potassium metal or sodium metal may be filled or / and deposited in the negative electrode current collector, and the lithium source material is lithium metal and / or lithium-rich material.

[0067] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0068] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode sheet and the negative electrode sheet.

[0069] In some embodiments, the separator is a separator. The present application has no particular limitation on the type of separator, and any known separator with a porous structure having good chemical stability and mechanical stability can be selected.

[0070] 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 special restrictions. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without special restrictions. The separator can be a separate component located between the positive and negative electrodes, or it can be attached to the surface of the positive and negative electrodes.

[0071] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode sheet and the negative electrode sheet and plays the role of transmitting ions and isolating the positive and negative electrodes.

[0072] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The present application has no specific restrictions on the type of electrolyte, which can be selected according to needs. The electrolyte can be liquid, gel or solid.

[0073] In some embodiments, the liquid electrolyte includes an electrolyte salt and a solvent.

[0074] In some embodiments, the electrolyte salt can 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 difluorooxalatoborate, lithium dioxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0075] In some embodiments, the solvent can be selected from at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, cyclopentane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent can also be selected from ether solvents. Ether solvents can include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether and crown ether.

[0076] The gel electrolyte includes a polymer-based electrolyte skeleton network combined with an ionic liquid-lithium salt.

[0077] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0078] As an example, the polymer solid electrolyte may be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, a single ion polymer, polyionic liquid-lithium salt, cellulose, and the like.

[0079] As an example, the inorganic solid electrolyte can be an oxide solid electrolyte (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superion conductor (lithium germanium phosphosulfide, silver germanium sulfide), amorphous sulfide) and one or more of a halide solid electrolyte, a nitride solid electrolyte and a hydride solid electrolyte.

[0080] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0081] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0082] In some embodiments, the electrode assembly is a laminate structure.

[0083] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets may be provided respectively, and the plurality of positive electrode sheets and the plurality of negative electrode sheets may be alternately stacked.

[0084] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet may be folded to form a plurality of stacked folded segments, with a positive electrode sheet being sandwiched between adjacent folded segments.

[0085] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of folded sections that are stacked.

[0086] As an example, a plurality of separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0087] As an example, the separator may be disposed continuously, and may be disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0088] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0089] In some embodiments, the electrode assembly is provided with tabs, which can lead current out of 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 the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film.

[0091] As an example, the battery cell may be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes a square-shell battery cell, a blade-shaped battery cell, a polygonal battery, such as a hexagonal battery.

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

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

[0094] In some embodiments, the battery may be a battery pack, which includes a case and battery cells, wherein the battery cells or battery modules are accommodated in the case.

[0095] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0096] In some embodiments, the battery may be an energy storage device, which includes an energy storage container, an energy storage cabinet, and the like.

[0097] With the development of new energy technology, batteries are used more and more widely, for example, in mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes and electric tools, etc.

[0098] The energy density of a battery cell refers to the amount of electrical energy that can be released per unit volume or per unit mass of the battery cell, and has an important impact on the economic benefits of the battery. The end caps of the battery cell are usually provided with electrode terminals, which are electrically connected to the electrode assemblies of the battery cell for outputting or inputting electrical energy into the battery cell. The current end caps are usually flat-plate structures, and the electrode terminals located on the side of the end caps facing the inside of the battery cell will occupy more of the internal space of the battery cell, making the space inside the battery cell that can be used to set up the electrode assemblies smaller. The electrode assemblies are the main functional components for providing electrical energy, and therefore will affect the improvement of the energy density of the battery cell.

[0099] Based on the above considerations, an embodiment of the present application provides a battery cell, which includes a shell, an electrode assembly and an electrode terminal. A housing cavity is provided inside the shell, and the shell includes a wall portion, the wall portion has a first recess and an electrode lead-out hole, the first recess is recessed relative to the surface of the wall portion facing the housing cavity, and the electrode lead-out hole penetrates the bottom wall of the first recess along the thickness direction of the wall portion. The electrode assembly is disposed in the housing cavity and includes a pole ear, the electrode terminal is disposed on the wall portion and electrically connected to the pole ear, and at least part of the electrode terminal located in the housing cavity is accommodated in the first recess. The first recess can be used to accommodate the electrode terminal to reduce the occupancy rate of the electrode terminal to the internal space of the battery cell, so that more space can be freed inside the battery cell to arrange the electrode assembly, thereby effectively improving the energy density of the battery cell.

[0100] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using batteries.

[0101] The electrical device may be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, and the like; the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, and the like; the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, and the like; the electric tool may include a metal cutting electric tool, a grinding electric tool, an assembly electric tool, and an electric tool for railways, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator, and an electric planer, and the like. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0102] It should be understood that the technical solutions described in the embodiments of the present application are not limited to the batteries and electrical equipment described above, but can also be applied to all batteries including battery boxes and electrical equipment using batteries. However, for the sake of simplicity, the following embodiments are described using electric vehicles as examples.

[0103] Figure 1 A schematic diagram of the structure of a vehicle provided for some embodiments of the present application.

[0104] Continue to refer Figure 1 The vehicle 1 is provided with a battery 2 inside, and the battery 2 can be provided at the bottom, head, or tail of the vehicle 1. The battery 2 can be used for powering the vehicle 1, for example, the battery 2 can be used as an operating power source for the vehicle 1.

[0105] The vehicle 1 may further include a controller 3 and a motor 4 , wherein the controller 3 is used to control the battery 2 to supply power to the motor 4 , for example, to meet the power requirements of starting, navigating, and driving the vehicle 1 .

[0106] In some embodiments of the present application, the battery 2 can not only serve as an operating power source for the vehicle 1, but also serve as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0107] Figure 2 An exploded schematic diagram of a battery provided for some embodiments of the present application.

[0108] Continue to refer Figure 2 The battery 2 includes a box body 5 and a battery cell, and the battery cell is accommodated in the box body 5.

[0109] The box 5 is used to accommodate the battery cells, and the box 5 can be of various structures. In some embodiments, the box 5 can include a first box portion 5a and a second box portion 5b, the first box portion 5a and the second box portion 5b cover each other, and the first box portion 5a and the second box portion 5b jointly define a storage space 5c for accommodating the battery cells. The second box portion 5b can be a hollow structure with one end open, the first box portion 5a is a plate-like structure, and the first box portion 5a covers the open side of the second box portion 5b to form a box 5 with a storage space 5c; the first box portion 5a and the second box portion 5b can also be hollow structures with one side open, and the open side of the first box portion 5a covers the open side of the second box portion 5b to form a box 5 with a storage space 5c. Of course, the first box portion 5a and the second box portion 5b can be of various shapes, such as a cylinder, a cuboid, etc.

[0110] In order to improve the sealing performance after the first box body part 5a and the second box body part 5b are connected, a sealing member, such as a sealant, a sealing ring, etc., may also be provided between the first box body part 5a and the second box body part 5b.

[0111] Assuming that the first box body portion 5a covers the top of the second box body portion 5b, the first box body portion 5a can also be called an upper box cover, and the second box body portion 5b can also be called a lower box.

[0112] In the battery 2, there can be one or more battery cells. If there are multiple battery cells, the multiple battery cells can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells are both connected in series and in parallel. The multiple battery cells can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the multiple battery cells is accommodated in the box 5; of course, multiple battery cells can also be connected in series, in parallel, or in mixed connection to form a battery module 6, and the multiple battery modules 6 are then connected in series, in parallel, or in mixed connection to form a whole, and accommodated in the box 5.

[0113] Figure 3 for Figure 2 Schematic diagram of the structure of the battery module shown.

[0114] In some embodiments, referring to the figure, there are multiple battery cells 7, and the multiple battery cells 7 are first connected in series, parallel or mixed to form a battery module 6. The multiple battery modules 6 are then connected in series, parallel or mixed to form a whole, and are accommodated in the box.

[0115] The multiple battery cells 7 in the battery module 6 can be electrically connected through a busbar component to achieve parallel connection, series connection or mixed connection of the multiple battery cells 7 in the battery module 6 .

[0116] Figure 4 A schematic diagram of an exploded structure of a battery cell provided in some embodiments of the present application, Figure 5A schematic diagram of a top view of a battery cell provided in some embodiments of the present application is shown. Figure 6 for Figure 5 Schematic diagram of the cross-sectional structure along AA.

[0117] refer to Figures 4 to 6 The embodiment of the present application provides a battery cell 7, which includes a housing 10, an electrode assembly 20 and an electrode terminal 30. The housing 10 is provided with a housing cavity 11. The housing 10 includes a wall portion 12. The wall portion 12 has a first recess 121 and an electrode lead-out hole 124. The first recess 121 is recessed relative to the surface of the wall portion 12 facing the housing cavity 11. The electrode lead-out hole 124 penetrates the bottom wall of the first recess 121 along the thickness direction X of the wall portion 12. The electrode assembly 20 is disposed in the housing cavity 11 and includes a tab. The electrode terminal 30 is disposed in the wall portion 12 and is electrically connected to the tab. At least a portion of the electrode terminal 30 located in the housing cavity 11 is accommodated in the first recess 121.

[0118] Exemplarily, the housing 10 is a component for forming an internal environment of the battery cell 7. The formed internal environment can be used to accommodate the electrode assembly 20, electrolyte and other components. Optionally, the housing 10 can be but is not limited to being made of metal or non-metal materials, for example, the metal material can be copper, aluminum or stainless steel, etc.; the non-metal material can be polyethylene, polypropylene or polyvinyl chloride, etc.

[0119] The electrode assembly 20 is a component in the battery cell 7 where electrochemical reactions occur. The electrode assembly 20 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly 20, and the parts of the positive and negative electrode sheets without active materials each constitute a tab. The positive tab and the negative tab may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the tabs are connected to the electrode terminals 30 to form a current loop.

[0120] The wall portion 12 of the housing 10 is provided with a first recess 121, and the first recess 121 is used to accommodate the electrode terminal 30. After the electrode terminal 30 is provided on the wall portion 12 and electrically connected to the electrode tab, a part of the electrode terminal 30 is accommodated in the first recess 121. The wall portion 12 may be integrally formed with the first recess 121, for example, the wall portion 12 is bent to form the first recess 121, or the wall portion 12 is integrally formed with the first recess 121 by casting or injection molding, etc.; the first recess 121 may also be processed on the wall portion 12 by milling, turning, wire cutting or laser cutting.

[0121] The electrode lead-out hole 124 can facilitate the connection between the electrode terminal 30 and a conductive element such as a busbar. The electrode lead-out hole 124 can be formed integrally on the wall 12, or the electrode lead-out hole 124 can be processed on the wall 12 by milling, turning, wire cutting or laser cutting.

[0122] The electrode terminal 30 may be inserted into the electrode lead-out hole 124 , that is, a portion of the electrode terminal 30 is located inside the housing 10 , and another portion of the electrode terminal 30 passes through the electrode lead-out hole 124 and extends outside the housing 10 .

[0123] The electrode terminals 30 may also be located inside the housing 10 , and the projection of the electrode lead-out hole 124 along the thickness direction X of the wall portion 12 at least partially overlaps with the projection of the electrode terminal 30 along the thickness direction X of the wall portion 12 .

[0124] The electrode terminal 30 may also extend into the electrode lead-out hole 124 , that is, a portion of the electrode terminal 30 is located inside the housing 10 , and another portion of the electrode terminal 30 is located in the electrode lead-out hole 124 .

[0125] The electrode lead-out hole 124 can facilitate the connection of the electrode terminal 30 with a conductive element such as a bus bar, thereby improving the convenience of use of the battery cell 7 .

[0126] Optionally, the projection shape of the first recess 121 along the thickness direction X of the wall 12 may be, but is not limited to, a circle, a rectangle, an ellipse, a triangle, or a trapezoid, etc., and may be selected according to the actual application environment. In one example, the projection shape of the first recess 121 along the thickness direction X of the wall 12 matches the projection shape of the portion of the electrode terminal 30 accommodated in the first recess 121 along the thickness direction X of the wall 12.

[0127] The first recess 121 of the above technical solution can be used to accommodate the electrode terminal 30 to reduce the occupancy rate of the electrode terminal 30 in the internal space of the battery cell 7, so that more space can be freed up inside the battery cell 7 to set the electrode assembly 20, thereby effectively improving the energy density of the battery cell 7.

[0128] In some embodiments, the wall portion 12 further has a second recess 122 , which is recessed relative to a surface of the wall portion 12 facing away from the accommodating cavity 11 , and a portion of the electrode terminal 30 is accommodated in the second recess 122 .

[0129] Exemplarily, a portion of the electrode terminals 30 are disposed on the side of the wall portion 12 facing the accommodating cavity 11, and a portion of the electrode terminals 30 are disposed on the side of the wall portion 12 facing away from the accommodating cavity 11. In other words, a portion of the electrode terminals 30 are disposed inside the housing 10, and a portion of the electrode terminals 30 are disposed outside the housing 10. The portion of the electrode terminals 30 located inside the housing 10 is used to connect to the tabs, and the portion of the electrode terminals 30 located outside the housing 10 is used to connect to conductive elements such as busbars to output or input electrical energy of the battery cell 7.

[0130] The wall portion 12 may be integrally formed with the second recess 122. For example, the wall portion 12 is bent by itself to form the first recess 121, or the wall portion 12 is integrally formed with the second recess 122 by casting or injection molding, etc.; the second recess 122 may also be machined on the wall portion 12 by milling, turning, wire cutting, or laser cutting.

[0131] Optionally, the projection shape of the second recess 122 along the thickness direction X of the wall portion 12 may be, but is not limited to, a circle, a rectangle, an ellipse, a triangle, or a trapezoid, etc., and may be selected according to the actual application environment. In one example, the projection shape of the second recess 122 along the thickness direction X of the wall portion 12 matches the projection shape of the portion of the electrode terminal 30 accommodated in the second recess 122 along the thickness direction X of the wall portion 12.

[0132] The second recess 122 of the above technical solution can be used to accommodate the portion of the electrode terminal 30 located outside the outer shell 10 to reduce the occupancy rate of the electrode terminal 30 on the external space of the battery cell 7, which is beneficial to reducing the overall volume of the battery cell 7, thereby further improving the energy density of the battery cell 7.

[0133] In some embodiments, a projection of the second recess 122 along the thickness direction X of the wall portion 12 surrounds a projection of the first recess 121 along the thickness direction X of the wall portion 12 .

[0134] The second recess 122 and the first recess 121 can be staggered with each other in the thickness direction X of the wall portion 12 to avoid interference between the first recess 121 and the second recess 122 to a certain extent. This can not only reduce the difficulty of setting the first recess 121 and the second recess 122, but also reduce the risk of breakage due to low structural strength caused by the local thickness of the wall portion 12 being too small, thereby improving the reliability of the battery cell 7.

[0135] In some embodiments, the projection shape of the second recess 122 along the thickness direction X of the wall portion 12 is a non-circular ring, such as a rectangular ring, a triangular ring, a trapezoidal ring, or an elliptical ring, etc. The electrode terminal 30 can be limited to block the rotation of the electrode terminal 30 along the circumferential direction of the wall portion 12, thereby improving the stability of the electrode terminal 30.

[0136] In some embodiments, the wall portion 12 further has a convex portion 123 , which protrudes from a surface of the wall portion 12 facing away from the accommodating cavity 11 , and a position of the convex portion 123 corresponds to a position of the first concave portion 121 .

[0137] For example, the convex portion 123 may be connected to the surface of the wall portion 12 facing away from the accommodating cavity 11 by welding, riveting or bonding, or may be integrally formed by the wall portion 12 by bending, casting or injection molding. As an example, a portion of the wall portion 12 is bent in a direction away from the accommodating cavity 11 to form the convex portion 123 on the side of the wall portion 12 facing away from the accommodating cavity 11 and a concave portion on the side of the wall portion 12 facing the accommodating cavity 11.

[0138] The above technical solution sets a convex portion 123 at the position of the first concave portion 121, which is beneficial to increasing the thickness of the wall portion 12 at the position of the first concave portion 121, thereby improving the overall structural strength of the wall portion 12, so as to reduce the risk of breakage due to low structural strength caused by the local thickness of the wall portion 12 being too small, thereby improving the reliability of the battery cell 7.

[0139] In some embodiments, the electrode terminal 30 has a third recess 31 , which is recessed relative to the surface of the electrode terminal 30 facing the wall portion 12 , and at least a portion of the protrusion 123 is accommodated in the third recess 31 .

[0140] Exemplarily, a portion of the electrode terminals 30 are disposed on the side of the wall portion 12 facing the accommodating cavity 11, and a portion of the electrode terminals 30 are disposed on the side of the wall portion 12 facing away from the accommodating cavity 11. In other words, a portion of the electrode terminals 30 are disposed inside the housing 10, and a portion of the electrode terminals 30 are disposed outside the housing 10. The portion of the electrode terminals 30 located inside the housing 10 is used to connect the tabs, and the portion of the electrode terminals 30 located outside the housing 10 is used to connect the busbars and other conductive elements to output or input the electrical energy of the battery cell 7. Among them, the portion of the electrode terminals 30 located inside the housing 10 is provided with a third recess 31.

[0141] The electrode terminal 30 may be formed with the third recess 31 in an integral manner. For example, the wall portion 12 is bent by itself to form the first recess 121, or the wall portion 12 is formed with the third recess 31 in an integral manner through a casting or injection molding process. Alternatively, the third recess 31 may be formed on the electrode terminal 30 through milling, turning, wire cutting, laser cutting or other processes.

[0142] Optionally, the projection shape of the third recess 31 along the thickness direction X of the wall 12 may be, but is not limited to, a circle, a rectangle, an ellipse, a triangle, or a trapezoid, etc., and may be selected according to the actual application environment. In one example, the projection shape of the third recess 31 along the thickness direction X of the wall 12 matches the projection shape of the portion of the protrusion 123 accommodated in the third recess 31 along the thickness direction X of the wall 12.

[0143] The third recess 31 of the above technical solution can be used to accommodate the protrusion 123 to reduce the size of the battery cell 7 in the thickness direction X of the wall portion 12, which is beneficial to reducing the overall volume of the battery cell 7, thereby further improving the energy density of the battery cell 7.

[0144] In some embodiments, the battery cell 7 further includes a seal 40 . In the thickness direction X, at least a portion of the seal 40 surrounds the electrode lead-out hole 124 and is sandwiched between the electrode terminal 30 and the bottom wall of the first recess 121 .

[0145] Exemplarily, at least a portion of the sealant 40 surrounds the electrode lead-out hole 124 and is sandwiched between the electrode terminal 30 and the bottom wall of the first recess 121. It can be understood that a portion of the sealant 40 surrounds the electrode lead-out hole 124 and is sandwiched between the electrode terminal 30 and the bottom wall of the first recess 121, or the entire sealant 40 surrounds the electrode lead-out hole 124 and is sandwiched between the electrode terminal 30 and the bottom wall of the first recess 121.

[0146] The sealing member 40 may be detachably connected between the electrode terminal 30 and the bottom wall of the first recess 121, or may be fixed between the electrode terminal 30 and the bottom wall of the first recess 121. In the case where the sealing member 40 may be fixed between the electrode terminal 30 and the bottom wall of the first recess 121, the sealing member 40 may be fixedly connected to the electrode terminal 30, the sealing member 40 may be fixedly connected to the bottom wall of the first recess 121, or the sealing member 40 may be fixedly connected to both the electrode terminal 30 and the bottom wall of the first recess 121.

[0147] As an example, the connection between the seal 40 and the electrode terminal 30 may be, but is not limited to, bolt connection, riveting, bonding or clamping, etc. The connection between the seal 40 and the bottom wall of the first recess 121 may be, but is not limited to, bolt connection, riveting, bonding or clamping, etc.

[0148] The seal 40 may be, but is not limited to, a block structure, a sheet structure, or a columnar structure, etc., and may be selected according to the actual application environment. The seal 40 may be, but is not limited to, made of materials such as silicone rubber, fluororubber, polytetrafluoroethylene, epoxy resin, or polyurethane.

[0149] The seal 40 of the above technical solution can form a seal between the electrode terminal 30 and the bottom wall of the first recess 121, so as to reduce the risk of external water vapor or impurities entering the battery cell 7 through the electrode lead-out hole 124 and causing damage to the battery cell 7. In addition, the seal 40 can be accommodated in the first recess 121, which can reduce the occupation of the internal space of the battery cell 7 by the seal 40, thereby effectively improving the energy density of the battery cell 7.

[0150] In some embodiments, the electrode terminal 30 is inserted into the electrode lead-out hole 124, and the electrode terminal 30 includes a pole 32 and a terminal plate 33. The pole 32 includes a connecting portion 321 and a limiting portion 322. The connecting portion 321 connects the limiting portion 322 and the terminal plate 33, and the bottom wall of the first recess 121 is clamped between the limiting portion 322 and the terminal plate 33.

[0151] Exemplarily, the terminal board 33 is located on the side of the wall portion 12 facing away from the accommodating cavity 11, that is, the terminal board 33 is located outside the housing 10, and the terminal board 33 serves as an external wiring part connected to the busbar. The connecting portion 321 of the pole 32 serves as a part fixedly connected to the wall portion 12, and the limiting portion 322 of the pole 32 serves as an internal wiring part electrically connected to the first pole lug.

[0152] The pole 32 can be detachably connected to the terminal board 33, or can be integrally provided on the terminal board 33. The pole 32 can be directly connected to the terminal board 33, or can be restricted to the terminal board 33 by other components. As an example, the connection method between the pole 32 and the terminal board 33 can be, but is not limited to, bolt connection, welding, riveting, bonding, or clamping.

[0153] As an example, the pole 32 and the terminal board 33 are an integrally formed structure. On the one hand, there is no need to connect the pole 32 and the terminal board 33 through an additional connection process, which simplifies the manufacturing process. At the same time, compared with connecting the pole 32 and the terminal board 33 through an additional connection process, the pole 32 and the terminal board 33 in an integral structure have a higher connection firmness.

[0154] The limiting portion 322 may be detachably connected to the connecting portion 321, or may be integrally provided on the connecting portion 321. The limiting portion 322 may be directly connected to the connecting portion 321, or may be limited to the connecting portion 321 by other components. As an example, the connection method between the limiting portion 322 and the connecting portion 321 may be, but is not limited to, bolt connection, welding, riveting, bonding, or clamping.

[0155] As an example, the connecting portion 321 and the limiting portion 322 are integrally formed. On the one hand, there is no need to connect the connecting portion 321 and the limiting portion 322 through an additional connection process, which simplifies the manufacturing process. At the same time, compared with connecting the connecting portion 321 and the limiting portion 322 through an additional connection process, the connecting portion 321 and the limiting portion 322 in an integral structure have a higher connection firmness.

[0156] Optionally, the area of ​​the cross section of the limiting portion 322 perpendicular to the thickness direction X of the wall portion 12 is larger than the area of ​​the cross section of the connecting portion 321 perpendicular to the thickness direction X of the wall portion 12, which is beneficial to increasing the flow area between the electrode tab of the electrode assembly 20 and the electrode terminal 30.

[0157] The above technical solution can further improve the connection firmness between the electrode terminal 30 and the wall portion 12 by clamping the bottom wall of the first recess 121 between the limiting portion 322 and the terminal plate 33 , thereby effectively improving the reliability of the battery cell 7 .

[0158] In some embodiments, the terminal plate 33 is provided with a through hole 331 , and the pole 32 passes through the electrode lead-out hole 124 and extends into the through hole 331 to be connected to the terminal plate 33 .

[0159] Exemplarily, a through hole 331 is provided at the approximate center of the terminal plate 33, and the aperture of the through hole 331 is adapted to the diameter of the connecting portion 321 of the pole 32. When the electrode terminal 30 is mounted on the wall portion 12, the terminal plate 33 needs to be fixed to the side of the wall portion 12 facing away from the accommodating cavity 11, and the connecting portion 321 of the pole 32 extends from the side of the wall portion 12 facing the accommodating cavity 11 to the outside of the housing 10 through the electrode lead-out hole 124, and the limiting portion 322 can abut against the side of the wall portion 12 facing the accommodating cavity 11, thereby limiting the pole 32. After the connecting portion 321 passes through the electrode lead-out hole 124, it further extends into the through hole 331 of the terminal plate 33, so as to fix the pole 32 to the terminal plate 33, thereby fixing the electrode terminal 30 to the wall portion 12.

[0160] In the above technical solution, the pole 32 extends into the through hole 331 and is connected to the terminal plate 33, which can increase the contact area between the pole 32 and the terminal plate 33, thereby facilitating the connection firmness between the pole 32 and the terminal plate 33, and further improving the overall reliability of the electrode terminal 30.

[0161] In some embodiments, the battery cell 7 further includes a first insulating member 50, which is disposed on a side of the wall portion 12 facing away from the accommodating cavity 11, and is used to insulate and isolate the electrode terminal 30 from the wall portion 12 to further improve the reliability of the battery cell 7. As an example, the first insulating member 50 is connected between the terminal plate 33 and the wall portion 12.

[0162] In some embodiments, the first insulating member 50 includes a first section and a second section connected to each other, the first section is connected between the terminal plate 33 and the wall portion 12, and the second section extends from an end of the first section away from the pole 32 along the thickness direction X of the wall portion 12, and is connected to a surface of one side of the terminal plate 33 away from the pole 32. The second section can reduce the risk of creepage between the terminal plate 33 and the wall portion 12, thereby further improving the insulation effect of the first insulating member 50.

[0163] In some embodiments, the first insulating member 50 is connected to the sealing member 40 , which can not only improve the stability of the sealing member 40 , but also further improve the sealing effect of the sealing member 40 .

[0164] In some embodiments, the battery cell 7 further includes a second insulating member 60, which is disposed on a side of the wall portion 12 facing the accommodating cavity 11, and is used to insulate and isolate the electrode terminal 30 from the wall portion 12 to further improve the reliability of the battery cell 7. As an example, the second insulating member 60 is connected between the limiting portion 322 and the wall portion 12.

[0165] In some embodiments, the second insulating member 60 is connected to the sealing member 40 , which can not only improve the stability of the sealing member 40 , but also further improve the sealing effect of the sealing member 40 .

[0166] In some embodiments, the seal 40 includes a first portion 41 and a second portion 42 connected to each other, wherein the first portion 41 is sandwiched between the inner wall of the electrode lead-out hole 124 and the connecting portion 321 , and the second portion 42 is sandwiched between the limiting portion 322 and the bottom wall of the first recess 121 .

[0167] The first part 41 can be detachably connected to the second part 42, or can be integrally provided on the second part 42. The first part 41 can be directly connected to the second part 42, or can be restricted to the second part 42 by other components. As an example, the connection method between the first part 41 and the second part 42 can be, but is not limited to, bolt connection, riveting, bonding, or clamping.

[0168] As an example, the first part 41 and the second part 42 are integrally formed. On the one hand, there is no need to connect the first part 41 and the second part 42 through an additional connection process, which simplifies the manufacturing process. At the same time, compared with connecting the first part 41 and the second part 42 through an additional connection process, the first part 41 and the second part 42 in an integral structure have a higher connection firmness.

[0169] Optionally, the first part 41 and the second part 42 may be made of the same material to simplify the manufacturing process and help reduce costs.

[0170] Optionally, the first portion 41 and the second portion 42 may be made of different materials, so as to be specifically selected according to different structural characteristics of the electrode lead-out hole 124 and the limiting portion 322 , which is beneficial to improving the adaptability of the sealing member 40 .

[0171] The seal 40 of the above technical solution can not only seal between the limiting portion 322 and the bottom wall of the first recess 121, but also seal between the inner wall of the electrode lead-out hole 124 and the connecting portion 321, so that the sealing path of the seal 40 can be increased, thereby further improving the sealing effect of the seal 40.

[0172] Figure 7 This is a schematic diagram of a top view of another battery cell provided in some embodiments of the present application. Figure 8 for Figure 7 Schematic diagram of the cross-sectional structure along BB.

[0173] Continue to refer Figures 7 and 8 In some embodiments, the seal 40 further includes a third portion 43 , the first portion 41 is connected between the second portion 42 and the third portion 43 , and the third portion 43 is sandwiched between the terminal board 33 and a surface of the wall portion 12 facing away from the accommodating cavity 11 .

[0174] The third part 43 may be detachably connected to the first part 41, or may be integrally provided on the first part 41. The first part 43 may be directly connected to the first part 41, or may be restricted to the first part 41 by other components. As an example, the connection between the first part 41 and the first part 41 may be, but is not limited to, bolt connection, riveting, bonding, or clamping.

[0175] As an example, the third part 43 and the first part 41 are integrally formed. On the one hand, there is no need to connect the third part 43 and the first part 41 through an additional connection process, which simplifies the manufacturing process. At the same time, compared with connecting the third part 43 and the first part 41 through an additional connection process, the third part 43 and the first part 41 in an integral structure have a higher connection firmness.

[0176] Optionally, the first part 41, the second part 42 and the third part 43 may be made of the same material to simplify the preparation process and help reduce costs.

[0177] Optionally, the first part 41 , the second part 42 and the third part 43 may be made of different materials, so as to be specifically selected according to the different structural characteristics of the electrode lead-out hole 124 , the limiting portion 322 and the terminal plate 33 , which is beneficial to improving the adaptability of the seal 40 .

[0178] The seal 40 of the above technical solution can further seal between the terminal plate 33 and the surface of the wall portion 12 facing away from the accommodating cavity 11 , so that the sealing path of the seal 40 can be further increased, thereby further improving the sealing effect of the seal 40 .

[0179] In some embodiments, a first dimension H1 of the wall portion 12 in the thickness direction X thereof and a second dimension H2 of the first recess 121 in the thickness direction X satisfy the relationship: 0<H2 / H1≤0.5.

[0180] The first dimension H1 of the wall portion 12 in the thickness direction X thereof refers to the maximum thickness of the wall portion 12 , and the second dimension H2 of the first recess 121 in the thickness direction X refers to the maximum depth of the first recess 121 .

[0181] As an example, the ratio H2 / H1 between the second size H2 and the first size H1 may be, but is not limited to, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, etc.

[0182] It can be understood that, the larger the ratio H2 / H1 between the second dimension H2 and the first dimension H1 is, the larger the proportion of the first recess 121 on the wall portion 12 along the thickness direction X of the wall portion 12 will be, and the worse the overall structural consistency of the wall portion 12 will be; the smaller the ratio H2 / H1 between the second dimension H2 and the first dimension H1 is, the fewer electrode terminals 30 can be accommodated in the first recess 121.

[0183] In this way, the above technical solution can reduce the occupancy rate of the internal space of the battery cell 7 by the electrode terminal 30 by setting the first dimension H1 of the wall portion 12 in its own thickness direction X and the second dimension H2 of the first recess 121 in the thickness direction X to satisfy the above relationship, thereby improving the energy density of the battery cell 7 while taking into account the overall structural consistency of the wall portion 12.

[0184] Further, the first size H1 and the second size H2 satisfy the relationship: 0.1≤H2 / H1≤0.25.

[0185] As an example, the ratio H2 / H1 between the second size H2 and the first size H1 may be, but is not limited to, 0.12, 0.14, 0.16, 0.18, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, etc.

[0186] In some embodiments, the first dimension H1 of the wall portion 12 in its thickness direction X satisfies the relationship: 1mm≤H1≤5mm. As an example, the first dimension H1 may be, but is not limited to, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm.

[0187] Furthermore, the first dimension H1 of the wall portion 12 in the thickness direction X satisfies the relationship: 2 mm ≤ H1 ≤ 3 mm. As an example, the first dimension H1 may be, but is not limited to, 2 mm,

[0188] 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm,

[0189] 2.9mm, 3mm.

[0190] In some embodiments, the second dimension H2 of the first recess 121 in the thickness direction X satisfies the relationship: 0.1 mm ≤ H2 ≤ 2 mm. As an example, the second dimension H2 may be, but is not limited to, 0.1 mm, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2 mm.

[0191] Further, the second dimension H2 of the first recess 121 in the thickness direction X satisfies the relationship: 0.3 mm ≤ H2 ≤ 1 mm. As an example, the second dimension H2 may be, but is not limited to, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, or 1 mm.

[0192] In some embodiments, the electrode terminal 30 located in the accommodation cavity 11 has a third dimension H3 in the thickness direction X, and the third dimension H3 satisfies the relationship: 1.5 mm≤H3≤5 mm.

[0193] As an example, the third size H3 may be, but is not limited to, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc.

[0194] It can be understood that, the smaller the third dimension H3 of the electrode terminal 30 located in the accommodating cavity 11 in the thickness direction X, the smaller the occupancy rate of the electrode terminal 30 in the internal space of the battery cell 7, and at the same time, the structural strength and connection firmness of the electrode terminal 30 are lower; the larger the third dimension H3 of the electrode terminal 30 located in the accommodating cavity 11 in the thickness direction X, the greater the occupancy rate of the electrode terminal 30 in the internal space of the battery cell 7, and at the same time, the structural strength and connection firmness of the electrode terminal 30 are higher.

[0195] In this way, the above technical solution sets the electrode terminal 30 located in the accommodating cavity 11 to have a third dimension H3 in the thickness direction X within the above range, which can reduce the occupancy rate of the electrode terminal 30 in the internal space of the battery cell 7 while ensuring the structural strength and connection firmness of the electrode terminal 30, thereby taking into account the energy density and reliability of the battery cell 7.

[0196] Further, the third size H3 satisfies the relationship: 2mm≤H3≤3mm. As an example, the third size H3 may be, but is not limited to, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, etc.

[0197] In some embodiments, the housing 10 includes a shell 10 a and an end cover 10 b , the shell 10 a has an opening and a receiving cavity 11 , the end cover 10 b is used to cover the opening, and the end cover 10 b is configured as a wall portion 12 .

[0198] Exemplarily, the end cap 10b refers to a component that covers the opening of the shell 10a to isolate the internal environment of the battery cell 7 from the external environment. Optionally, the shape of the end cap 10b can be adapted to the shape of the shell 10a to match the shell 10a. Optionally, the end cap 10b can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 10b is not easy to deform when it is squeezed and collided, so that the battery cell 7 can have a higher structural strength and reliability can also be improved. Functional components such as terminal groups can be arranged on the end cap 10b. In some embodiments, the end cap 10b can also be provided with a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 7 reaches a threshold. The material of the end cap 10b can also be a variety of materials. For example, the end cap 10b can be but not limited to being made of metal or non-metallic materials. For example, the metal material can be copper, aluminum or stainless steel, etc.; the non-metallic material can be polyethylene, polypropylene or polyvinyl chloride, etc.

[0199] The shell 10a is a component used to cooperate with the end cap 10b to form the internal environment of the battery cell 7. The internal environment formed can be used to accommodate the electrode assembly 20, electrolyte and other components. The shell 10a and the end cap 10b can be independent components, and an opening can be set on the shell 10a, and the internal environment of the battery cell 7 is formed by covering the opening with the end cap 10b. Optionally, the end cap 10b and the shell 10a can also be integrated. Specifically, the end cap 10b and the shell 10a can form a common connection surface before other components are put into the shell, and when the interior of the shell 10a needs to be encapsulated, the end cap 10b is covered with the shell 10a. The shell 10a can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 10a can be determined according to the specific shape and size of the electrode assembly 20. The material of the shell 10a can be various. For example, the shell 10a can be made of, but not limited to, metal or non-metallic materials.

[0200] For example, the metal material may be copper, aluminum or stainless steel, etc.; the non-metal material may be polyethylene, polypropylene or polyvinyl chloride, etc.

[0201] Optionally, the end cap 10b may be detachably connected to the housing 10a, or may be integrally provided on the housing 10a. The end cap 10b may be directly connected to the housing 10a, or may be restricted to the housing 10a by other components. As an example, the connection method between the end cap 10b and the housing 10a may be, but is not limited to, welding, riveting, or bonding.

[0202] According to some embodiments of the present application, the present application also provides a battery, comprising a battery cell 7 of any of the above schemes.

[0203] According to some embodiments of the present application, the present application further provides an electrical device, comprising a battery cell 7 according to any of the above schemes, and the battery cell 7 is used to provide electrical energy.

[0204] In order to better understand the battery cell 7 provided in the embodiment of the present application, based on the same inventive concept, an embodiment of the above-mentioned battery cell 7 in actual application is provided here for illustration.

[0205] The embodiment of the present application provides a battery cell 7, which includes a housing 10, an electrode assembly 20, an electrode terminal 30 and a sealing member 40. The housing 10 is provided with a housing cavity 11. The housing 10 includes a wall portion 12, the wall portion 12 has a first recess 121 and an electrode lead-out hole 124, the first recess 121 is recessed relative to the surface of the wall portion 12 facing the housing cavity 11, and the electrode lead-out hole 124 penetrates the bottom wall of the first recess 121 along the thickness direction X of the wall portion 12. The electrode assembly 20 is disposed in the housing cavity 11 and includes a tab, the electrode terminal 30 is disposed in the wall portion 12 and electrically connected to the tab, and part of the electrode terminal 30 is accommodated in the first recess 121. In the thickness direction X, at least part of the sealing member 40 surrounds the electrode lead-out hole 124 and is sandwiched between the electrode terminal 30 and the bottom wall of the first recess 121.

[0206] The first recess 121 of the above technical solution can be used to accommodate the electrode terminal 30 and the seal 40 to reduce the occupancy rate of the electrode terminal 30 and the seal 40 in the internal space of the battery cell 7, so that more space can be freed up inside the battery cell 7 to set the electrode assembly 20, thereby effectively improving the energy density of the battery cell 7.

[0207] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0208] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: A housing having a receiving cavity therein, the housing comprising a wall portion, the wall portion having a first recess and an electrode lead-out hole, the first recess being recessed relative to a surface of the wall portion facing the receiving cavity, and the electrode lead-out hole penetrating a bottom wall of the first recess along a thickness direction of the wall portion; An electrode assembly, disposed in the accommodating cavity and comprising an electrode tab; The electrode terminal is disposed on the wall portion and electrically connected to the electrode tab, and at least a portion of the electrode terminal located in the accommodation cavity is accommodated in the first recess.

2. The battery cell according to claim 1, characterized in that: The wall portion further has a second recessed portion, which is recessed relative to a surface of the wall portion on a side facing away from the accommodation cavity, and a portion of the electrode terminal is accommodated in the second recessed portion.

3. The battery cell according to claim 2, characterized in that: A projection of the second recessed portion along the thickness direction of the wall portion surrounds a projection of the first recessed portion along the thickness direction.

4. The battery cell according to claim 1, characterized in that: The wall portion further has a convex portion, which protrudes from a surface of the wall portion facing away from the accommodating cavity, and a position of the convex portion corresponds to a position of the first concave portion.

5. The battery cell according to claim 4, characterized in that: The electrode terminal has a third recessed portion that is recessed relative to a surface of the electrode terminal that faces the wall portion, and at least a portion of the protrusion is accommodated in the third recessed portion.

6. The battery cell according to claim 1, characterized in that: The battery cell further includes a sealing member, wherein at least a portion of the sealing member surrounds the electrode lead-out hole in the thickness direction and is sandwiched between the electrode terminal and a bottom wall of the first recess.

7. The battery cell according to claim 6, characterized in that: The electrode terminal is passed through the electrode lead-out hole, and the electrode terminal includes a pole and a terminal plate. The pole includes a connecting portion and a limiting portion. The connecting portion connects the limiting portion and the terminal plate, and the bottom wall of the first recess is clamped between the limiting portion and the terminal plate.

8. The battery cell according to claim 7, characterized in that: The terminal plate is provided with a through hole, and the pole passes through the electrode lead-out hole and extends into the through hole to be connected with the terminal plate.

9. The battery cell according to claim 7, characterized in that: The sealing member includes a first portion and a second portion which are connected to each other. The first portion is sandwiched between the inner wall of the electrode lead-out hole and the connecting portion, and the second portion is sandwiched between the limiting portion and the bottom wall of the first recess.

10. The battery cell according to claim 9, characterized in that: The sealing member further includes a third portion, the first portion is connected between the second portion and the third portion, and the third portion is sandwiched between the terminal board and a surface of the wall portion facing away from the accommodating cavity.

11. The battery cell according to claim 1, characterized in that: A first dimension H1 of the wall portion in the thickness direction thereof and a second dimension H2 of the first recessed portion in the thickness direction satisfy the relationship: 0<H2 / H1≤0.

5.

12. The battery cell according to claim 1, characterized in that: The electrode terminal located in the accommodation cavity has a third dimension H3 in the thickness direction, and the third dimension H3 satisfies the relationship: 1.5 mm≤H3≤5 mm.

13. The battery cell according to any one of claims 1 to 12, characterized in that: The housing comprises a shell and an end cover, the shell has an opening and the accommodating cavity, and the end cover is used to cover the opening; The end cap is configured as the wall portion.

14. A battery, characterized in that: The invention comprises a plurality of battery cells according to any one of claims 1 to 13.

15. An electrical device, characterized in that: The invention comprises a battery cell as claimed in any one of claims 1 to 13, wherein the battery cell is used to provide electrical energy.

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