Battery cell, battery, and electric device

Abstract

The present application provides a battery cell, a battery, and an electric device. The battery cell comprises a casing, an electrode assembly, and electrode terminals. The casing is internally provided with an accommodating cavity; the casing comprises a wall portion; the wall portion has first recesses and electrode lead-out holes; the first recesses are recessed with respect to the surface of the wall portion facing the accommodating cavity; and the electrode lead-out holes pass through the bottom walls of the first recesses in the thickness direction of the wall portion. The electrode assembly is arranged in the accommodating cavity and comprises tabs; the electrode terminals are arranged on the wall portion and electrically connected to the tabs; and at least parts of the electrode terminals located in the accommodating cavity are accommodated in the first recesses.

Description

Battery cell, battery and electric device

[0001] Cross-reference to Related Applications

[0002] This application claims priority to Chinese Patent Application No. 202420761045.X, filed on April 12, 2024, entitled “Battery cell, battery and electric device”, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present application relates to the technical field of batteries, in particular to a battery cell, a battery and an electric device. BACKGROUND

[0004] With the development of new energy technology, batteries are increasingly widely used, such as in mobile phones, notebook computers, electric cars, electric vehicles, electric aircraft, electric ships, electric toy cars, electric toy ships, electric toy aircraft and electric tools.

[0005] The energy density of a battery cell refers to the electrical energy that can be released by a battery cell per unit volume or unit mass, which has an important influence on the economic benefits of the battery. Therefore, how to effectively improve the energy density of the battery cell is a problem to be solved in the battery technology. SUMMARY

[0006] In view of the above problems, the present application provides a battery cell, a battery and an electric device, which can effectively improve the energy density of the battery cell.

[0007] In a first aspect, the embodiments of the present application provide a battery cell, which comprises a shell, an electrode assembly and an electrode terminal. The shell has an accommodating cavity inside. The shell comprises a wall portion, the wall portion has a first recess and an electrode lead-out hole. The first recess is recessed with respect to the surface of the wall portion facing the accommodating cavity. 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 arranged in the accommodating cavity and comprises a tab. The electrode terminal is arranged on the wall portion and electrically connected to the tab. At least part of the electrode terminal in the accommodating cavity is accommodated in the first recess.

[0008] The first recess of the above technical solution can be used to accommodate the electrode terminal, so as to reduce the occupancy rate of the electrode terminal to the internal space of the battery cell, so that more space can be left in the battery cell to arrange the electrode assembly, thereby effectively improving the energy density of the battery cell.

[0009] In some embodiments of the first aspect, the wall portion further has a second recess, the second recess is recessed with respect to the side surface of the wall portion facing away from the accommodating cavity, and part of the electrode terminal is accommodated in the second recess.

[0010] The second recess can be used to accommodate the part of the electrode terminal located outside the shell, so as to reduce the occupancy of the electrode terminal to the external space of the battery monomer, facilitate the reduction of the overall volume of the battery monomer, and further improve the energy density of the battery monomer.

[0011] In some embodiments of the first aspect, a projection of the second recess along the thickness direction of the wall portion encircles a projection of the first recess along the thickness direction.

[0012] The second recess and the first recess can be staggered in the thickness direction of the wall portion, so as to avoid interference between the first recess and the second recess to some extent, reduce the difficulty of setting the first recess and the second recess, reduce the risk of fracture caused by the local thickness of the wall portion being too small and the structural strength being too low, and improve the reliability of the battery monomer.

[0013] In some embodiments of the first aspect, the wall portion further has a protrusion, the protrusion protruding from a surface of the wall portion facing away from the accommodation cavity, and the position of the protrusion corresponds to the position of the first recess.

[0014] The protrusion is arranged at the position of the first recess, so as to improve the thickness of the wall portion at the position of the first recess, improve the overall structural strength of the wall portion, reduce the risk of fracture caused by the local thickness of the wall portion being too small and the structural strength being too low, and improve the reliability of the battery monomer.

[0015] In some embodiments of the first aspect, the electrode terminal has a third recess, the third recess is recessed relative to a surface of the electrode terminal facing the wall portion, and at least part of the protrusion is accommodated in the third recess.

[0016] The third recess can be used to accommodate the protrusion, so as to reduce the size of the battery monomer in the thickness direction of the wall portion, facilitate the reduction of the overall volume of the battery monomer, and further improve the energy density of the battery monomer.

[0017] In some embodiments of the first aspect, the battery monomer further comprises a sealing member, and in the thickness direction, at least part of the sealing member encircles the electrode lead-out hole and is clamped between the electrode terminal and the bottom wall of the first recess.

[0018] The electrode lead-out hole can facilitate the connection of the electrode terminal with a conductive element such as a busbar, and improve the use convenience of the battery monomer; the sealing member can form a seal between the electrode terminal and the bottom wall of the first recess, so as to reduce the risk of damage to the battery monomer caused by external water vapor or impurities entering the inside of the battery monomer through the electrode lead-out hole. In addition, the sealing member can be accommodated in the first recess, so as to reduce the occupancy of the sealing member to the internal space of the battery monomer, and effectively improve the energy density of the battery monomer.

[0019] In some embodiments of the first aspect, the electrode terminal is provided through the electrode lead-out hole, the electrode terminal comprises a pole and a terminal plate, the pole comprises 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 portion is clamped between the limiting portion and the terminal plate.

[0020] The above technical solution can further improve the connection firmness between the electrode terminal and the wall portion, thereby effectively improving the reliability of the battery monomer.

[0021] In some embodiments of the first aspect, the terminal plate is provided with a through hole, the pole is provided through the electrode lead-out hole and extends into the through hole to be connected with the terminal plate.

[0022] The above technical solution can improve the contact area between the pole and the terminal plate, thereby facilitating the improvement of the connection firmness between the pole and the terminal plate, so as to further improve the reliability of the electrode terminal as a whole.

[0023] In some embodiments of the first aspect, the sealing member comprises a first portion and a second portion connected with each other, the first portion is clamped between the inner wall of the electrode lead-out hole and the connecting portion, and the second portion is clamped between the limiting portion and the bottom wall of the first recess portion.

[0024] The sealing member of the above technical solution can not only seal between the limiting portion and the bottom wall of the first recess portion, but also seal between the inner wall of the electrode lead-out hole and the connecting portion, so that the sealing path of the sealing member can be increased, thereby further improving the sealing effect of the sealing member.

[0025] In some embodiments of the first aspect, the sealing member further comprises a third portion, the first portion is connected between the second portion and the third portion, and the third portion is clamped between the terminal plate and the surface of the wall portion facing away from the accommodating cavity.

[0026] The sealing member of the above technical solution can further seal between the terminal plate and the surface of the wall portion facing away from the accommodating cavity, so that the sealing path of the sealing member can be further increased, thereby further improving the sealing effect of the sealing member.

[0027] In some embodiments of the first aspect, the first dimension H1 of the wall portion in the thickness direction of the wall portion and the second dimension H2 of the first recess portion in the thickness direction satisfy the relationship: 0

[0028] The above technical solution sets the first dimension H1 of the wall portion in the thickness direction of the wall portion and the second dimension H2 of the first recess portion in the thickness direction to satisfy the above relationship, so that the occupancy rate of the electrode terminal to the internal space of the battery monomer can be reduced, the structural consistency of the wall portion as a whole can be considered, and the energy density of the battery monomer can be improved.

[0029] In some embodiments of the first aspect, 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: 1.5mm≤H3≤5mm.

[0030] The electrode terminal located in the accommodation cavity has a third dimension H3 in the thickness direction, which is set in the above range, which can reduce the occupancy of the electrode terminal to the internal space of the battery monomer, while ensuring the structural strength and connection firmness of the electrode terminal, so as to balance the energy density and reliability of the battery monomer.

[0031] In some embodiments of the first aspect, the shell comprises a shell body and an end cover, the shell body has an opening and an accommodation cavity, and the end cover is used to cover the opening and is configured as a wall part.

[0032] In the second aspect, the present application provides a battery comprising the battery monomer provided in any of the embodiments of the first aspect.

[0033] In the third aspect, the present application provides a power consumption device comprising the battery monomer provided in any of the embodiments of the first aspect, and the battery monomer is used to provide electric energy.

[0034] The above description is only a summary of the technical solutions of the present application. In order to make the technical means of the present application more clear, the present application can be implemented according to the content of the description, and in order to make the above and other purposes, characteristics and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0035] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments and are not meant to limit the present application. Moreover, the same reference numerals in the accompanying drawings indicate the same or similar components. In the drawings:

[0036] FIG. 1 is a structural schematic diagram of a vehicle provided in some embodiments of the present application;

[0037] FIG. 2 is an exploded structural schematic diagram of a battery provided in some embodiments of the present application;

[0038] FIG. 3 is a structural schematic diagram of a battery module provided in some embodiments of the present application;

[0039] FIG. 4 is an exploded structural schematic diagram of a battery monomer provided in some embodiments of the present application;

[0040] FIG. 5 is a top view structural schematic diagram of a battery monomer provided in some embodiments of the present application;

[0041] Fig. 6 is a schematic view of a cross-sectional structure of Fig. 5 along A-A;

[0042] Fig. 7 is a schematic view of a top structure of another battery cell according to some embodiments of the present application;

[0043] Fig. 8 is a schematic view of a cross-sectional structure of Fig. 7 along B-B.

[0044] The reference signs in the detailed description of the embodiments are as follows: 1, vehicle; 2, battery; 3, controller; 4, motor; 5, box; 5a, first box part; 5b, second box part; 5c, accommodation space; 6, battery module; 7, battery cell; 10, housing; 10a, shell; 10b, end cover; 11, accommodation cavity; 12, wall part; 121, first recess; 122, second recess; 123, convex part; 124, electrode lead-out hole; 20, electrode assembly; 30, electrode terminal; 31, third recess; 32, pole; 321, connecting part; 322, limiting part; 33, terminal plate; 331, through hole; 40, sealing member; 41, first part; 42, second part; 43, third part; 50, first insulation member; 60, second insulation member; X, thickness direction. DETAILED DESCRIPTION

[0045] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0046] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion. The terms "first", "second" and the like in the specification and claims of the present application and the above description of drawings are used to distinguish different objects, not to describe a particular order or primary and secondary relationship.

[0047] In the present application, the phrase "embodiment" means that the specific features, structures or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The phrase appears at various places in the specification does not necessarily refer to the same embodiment, nor is it mutually exclusive or alternative to other embodiments.

[0048] In the description of the present application, it should be noted that unless specifically defined and limited otherwise, the terms "mount", "connect", "connection", "attach" should be broadly interpreted, for example, it can be fixed connection, or detachable connection, or integrally connected, it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0049] The term "and / or" in the present application is only to describe the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in the present application generally represents that the front and rear associated objects have an "or" relationship.

[0050] In the embodiments of the present application, the same reference signs represent the same parts, and for the sake of brevity, the detailed description of the same parts is omitted in different embodiments. It should be understood that the thickness, length and width of various components in the embodiments of the present application shown in the drawings, and the overall thickness, length and width of the integrated device are only exemplary and should not constitute any limitation on the present application.

[0051] "Multiple" appearing in the present application means more than two (including two).

[0052] The term "parallel" in the present application not only includes the case of absolute parallel, but also includes the case of approximately parallel which is generally recognized in engineering; at the same time, "vertical" also not only includes the case of absolute vertical, but also includes the case of approximately vertical which is generally recognized in engineering.

[0053] In the embodiments of the present application, the battery cell can be a secondary battery cell, which refers to a battery cell that can be activated by charging after discharging to continue to use.

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

[0055] The battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode and a negative electrode. During the charging and discharging process of the battery cell, active ions (such as lithium ions) are inserted and extracted between the positive electrode and the negative electrode.

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

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

[0058] As an example, the cathode current collector has two surfaces opposite in the thickness direction thereof, and the cathode active material layer is disposed on either one or both of the two surfaces of the cathode current collector.

[0059] As an example, the cathode current collector can employ 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, a carbon electrode, carbon, nickel, or titanium, etc. can be employed. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material base material (such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0060] As an example, the cathode active material layer includes a cathode active material. The cathode active material can include at least one of a lithium-containing phosphate, a lithium transition metal oxide, and a modified compound of each thereof. However, the present application is not limited to these materials, and other conventional materials that can be used as a battery cathode active material can also be used. These cathode active materials can be used alone only one or two or more can be used in combination. Among them, examples of the lithium-containing phosphate can include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (which can also be 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 manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon. Examples of the lithium transition metal oxide can 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 (which can also be referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O2 (which can also be referred to as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2 (which can also be referred to as NCM 211 ), LiNi 0.6 Co0.2 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 (e.g., LiNi 0.80 Co 0.15 Al 0.05 O2), and modified compounds thereof.

[0061] In some embodiments, the positive electrode can employ a foamed carbon or a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, or foamed alloy, etc. When the foamed metal is used as the positive electrode, the surface of the foamed metal can not be provided with the positive electrode active material, or of course can be provided with the positive electrode active material. As an example, the foamed metal can also be filled or / and deposited with a lithium source material, a potassium metal, or a sodium metal, the lithium source material being a lithium metal and / or a lithium-rich material.

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

[0063] As an example, the negative electrode current collector can employ a metal foil, a foamed metal, a foamed carbon, 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, a carbon electrode, a nickel electrode, or a titanium electrode, etc. can be employed. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, or foamed alloy, etc. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material base material (e.g., polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0064] As an example, the negative electrode active material can employ a negative electrode active material known in the art for use in a battery cell. As an example, the negative electrode active material can include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, a silicon-based material, a tin-based material, and lithium titanate, etc. The silicon-based material can be selected from at least one of elemental silicon, a silicon oxide compound, a silicon-carbon composite, a silicon-nitrogen composite, and a silicon alloy. The tin-based material can be selected from at least one of elemental tin, a tin oxide compound, and a tin alloy. However, the present application is not limited to these materials, and other conventional materials that can be used as a battery negative electrode active material can also be used. These negative electrode active materials can be used alone or in combination of two or more.

[0065] In some embodiments, the negative electrode can employ a foamed carbon or a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, or foamed alloy, etc. When the foamed metal is used as the negative electrode tab, the surface of the foamed metal can be free of the negative active material, or can be provided with the negative active material.

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

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

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

[0069] In some embodiments, the separator is a separator film. The type of the separator film is not particularly limited in the present application, and any known porous structure separator film with good chemical stability and mechanical stability can be selected.

[0070] As an example, the main material of the separator film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride, and ceramic. The separator film can be a single-layer film or a multi-layer composite film, and is not particularly limited. When the separator film is a multi-layer composite film, the materials of the layers can be the same or different, and are not particularly limited. The separator can be a separate component located between the positive and negative electrodes, or can be attached to the surface of the positive and negative electrodes.

[0071] In some embodiments, the separator is a solid-state electrolyte. The solid-state electrolyte is disposed between the positive electrode tab and the negative electrode tab, and simultaneously functions as ion transmission and separation of the positive and negative electrodes.

[0072] In some embodiments, the battery cell further comprises an electrolyte, which functions as ion conduction between the positive and negative electrodes. The type of the electrolyte is not particularly limited in the present application, and can be selected according to the requirements. The electrolyte can be in a liquid state, a gel state, or a solid state.

[0073] In some embodiments, the liquid electrolyte comprises 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 bisfluorosulfonylimide, lithium bistrifluoromethylsulfonylimide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluoroboric oxalate, lithium bioric phosphate, lithium difluoroboric dioxalate, and lithium tetrafluorophosphoric oxalate.

[0075] In some embodiments, the solvent can 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, 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, butyl sulfone, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent can also be selected from an ether solvent. The ether solvent 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, methyl tetrahydrofuran, diphenyl ether, and a crown ether.

[0076] The gel electrolyte includes a polymer as a backbone network of the electrolyte, in combination with an ionic liquid-lithium salt.

[0077] The solid electrolyte includes a polymer solid electrolyte, an inorganic solid electrolyte, and a composite solid electrolyte.

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

[0079] As an example, the inorganic solid electrolyte can be one or more of an oxide solid electrolyte (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON thin film), a sulfide solid electrolyte (crystalline lithium superionic conductor (lithium germanium phosphorous sulfide, argyrodite), amorphous sulfide), and 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. The positive electrode sheet and the negative electrode sheet are wound into the wound structure.

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

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

[0084] As an example, a plurality of positive electrode sheets can be provided, and the negative electrode sheet can be folded to form a plurality of folded segments that are stacked, and one positive electrode sheet can be interposed between adjacent folded segments.

[0085] As an example, the positive electrode sheet and the negative electrode sheet can each be folded to form a plurality of folded segments that are stacked.

[0086] As an example, the separators can be provided in plurality, each provided between any adjacent positive electrode sheet or negative electrode sheet.

[0087] As an example, the separators can be provided in plurality, each provided between any adjacent positive electrode sheet or negative electrode sheet.

[0088] In some embodiments, the electrode assembly can have a shape of a cylinder, a flat, or a polygonal prism, etc.

[0089] In some embodiments, the electrode assembly can be provided with tabs, which can lead current out of the electrode assembly. The tabs can include positive tabs and negative tabs.

[0090] In some embodiments, the battery cell can include a casing. The casing can be used to enclose components such as the electrode assembly and the electrolyte. The casing can be a steel casing, an aluminum casing, a plastic casing (e.g., polypropylene), a composite metal casing (e.g., a copper-aluminum composite casing), or an aluminum-plastic film, etc.

[0091] 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, which can include a square battery cell, a blade battery cell, a polygonal battery cell (e.g., a hexagonal battery cell), etc.

[0092] A battery as referred to in embodiments of the present application can refer to a single physical module that includes one or more battery cells to provide a higher voltage and capacity.

[0093] In some embodiments, the battery can be a battery module, in which a plurality of battery cells are arranged and fixed to form a battery module.

[0094] In some embodiments, the battery can be a battery pack, which can include a box and battery cells or battery modules housed in the box.

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

[0096] In some embodiments, the battery can be an energy storage device. The energy storage device can include an energy storage container, an energy storage cabinet, etc.

[0097] With the development of new energy technologies, batteries are increasingly widely used, for example, in mobile phones, notebook computers, 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 electrical energy that can be released by the battery cell per unit volume or per unit mass, which has an important influence on the economic benefits of the battery. An electrode terminal is usually arranged on the end cover of the battery cell, and the electrode terminal is electrically connected with the electrode assembly of the battery cell to output or input the electrical energy of the battery cell. The current end cover is usually a flat plate structure, and the electrode terminal on the side of the end cover facing the inside of the battery cell occupies a large amount of internal space of the battery cell, so that the space in the battery cell that can be used to arrange the electrode assembly is reduced. Since the electrode assembly is the main functional component for providing electrical energy, the improvement of the energy density of the battery cell is affected.

[0099] Based on the above considerations, the embodiments of the present application provide a battery cell, which comprises a shell, an electrode assembly and an electrode terminal. The shell has an accommodating cavity inside, and the shell comprises 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 accommodating 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 arranged in the accommodating cavity and comprises a tab. The electrode terminal is arranged on the wall portion and is electrically connected to the tab. At least part of the electrode terminal located in the accommodating 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 on the internal space of the battery cell, so that more space in the battery cell can be left for arranging 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 suitable for batteries and electric devices using batteries.

[0101] The electric device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy and an electric tool, etc. The vehicle can be a fuel automobile, a gas automobile or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile or a range extended automobile, etc. The spacecraft includes an airplane, a rocket, a space shuttle and a spacecraft, etc. The electric toy includes a fixed or mobile electric toy, such as a game console, an electric automobile toy, an electric ship toy and an electric airplane toy, etc. The electric tool includes a metal cutting electric tool, a grinding electric tool, an assembling electric tool and a railway electric tool, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact electric drill, a concrete vibrator and an electric planer, etc. The embodiments of the present application do not specially limit the above electric devices.

[0102] It should be understood that the technical solutions described in the embodiments of the present application are not only limited to the above described batteries and electric devices, but can also be applied to all batteries including battery boxes and electric devices using batteries. However, for the sake of simplicity, the following embodiments are described by taking an electric vehicle as an example.

[0103] FIG. 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application.

[0104] With continued reference to FIG. 1, the vehicle 1 is provided with a battery 2, which can be arranged at the bottom, head or tail of the vehicle 1. The battery 2 can be used for power supply of the vehicle 1, for example, the battery 2 can be used as the operating power source of the vehicle 1.

[0105] The vehicle 1 can also include a controller 3 and a motor 4, the controller 3 being used to control the battery 2 to supply power to the motor 4, for example, for the power demand of the vehicle 1 during starting, navigation and driving.

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

[0107] FIG. 2 is an exploded schematic diagram of a battery according to some embodiments of the present application.

[0108] With continued reference to FIG. 2, the battery 2 includes a box body 5 and battery cells, the battery cells being accommodated in the box body 5.

[0109] The box body 5 is used to accommodate the battery cells, and the box body 5 can have various structures. In some embodiments, the box body 5 can include a first box body part 5a and a second box body part 5b, the first box body part 5a and the second box body part 5b being mutually coverable, and the first box body part 5a and the second box body part 5b together defining an accommodation space 5c for accommodating the battery cells. The second box body part 5b can be a hollow structure with one end open, and the first box body part 5a can be a plate-like structure, the first box body part 5a being coverable on the open end of the second box body part 5b to form the box body 5 with the accommodation space 5c; or the first box body part 5a and the second box body part 5b can both be hollow structures with one side open, the open side of the first box body part 5a being coverable on the open side of the second box body part 5b to form the box body 5 with the accommodation space 5c. Of course, the first box body part 5a and the second box body part 5b can have various shapes, such as a cylinder, a cuboid, etc.

[0110] To improve the sealing performance of the first box body part 5a and the second box body part 5b after being connected, a sealing member such as sealing glue, a sealing ring, etc. can be arranged between the first box body part 5a and the second box body part 5b.

[0111] Supposing that the first box body part 5a is coverable on the top of the second box body part 5b, the first box body part 5a can also be referred to as an upper box cover, and the second box body part 5b can also be referred to as a lower box body.

[0112] In the battery 2, the battery cell can be one or multiple. If the battery cell is multiple, the multiple battery cells can be connected in series, in parallel or in a mixed manner. The mixed manner means that the multiple battery cells are connected in series and in parallel. The multiple battery cells can be directly connected in series, in parallel or in a mixed manner, and the whole of the multiple battery cells is accommodated in the box 5. Of course, the multiple battery cells can be first connected in series, in parallel or in a mixed manner to form a battery module 6, and the multiple battery modules 6 are connected in series, in parallel or in a mixed manner to form a whole and are accommodated in the box 5.

[0113] Fig. 3 is a structural schematic diagram of the battery module shown in Fig. 2.

[0114] In some embodiments, still referring to the drawings, the battery cell 7 is multiple, and the multiple battery cells 7 are first connected in series, in parallel or in a mixed manner to form a battery module 6. The multiple battery modules 6 are connected in series, in parallel or in a mixed manner 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 realize the parallel connection, series connection or mixed connection of the multiple battery cells 7 in the battery module 6.

[0116] Fig. 4 is an exploded structural schematic diagram of a battery cell provided in some embodiments of the present application, Fig. 5 is a top structural schematic diagram of a battery cell provided in some embodiments of the present application, and Fig. 6 is a sectional structural schematic diagram of Fig. 5 along A-A.

[0117] Referring to Figs. 4 to 6, the embodiments of the present application provide a battery cell 7, which comprises a shell 10, an electrode assembly 20 and an electrode terminal 30. The shell 10 is internally provided with an accommodation cavity 11. The shell 10 comprises a wall portion 12, the wall portion 12 is provided with a first recess 121 and an electrode lead-out hole 124. The first recess 121 is recessed relative to a surface of the wall portion 12 facing the accommodation cavity 11. The electrode lead-out hole 124 penetrates a bottom wall of the first recess 121 along a thickness direction X of the wall portion 12. The electrode assembly 20 is arranged in the accommodation cavity 11 and comprises a tab. The electrode terminal 30 is arranged on the wall portion 12 and is electrically connected to the tab. At least part of the electrode terminal 30 located in the accommodation cavity 11 is accommodated in the first recess 121.

[0118] Exemplarily, the shell 10 is a component for forming an internal environment of the battery cell 7. The internal environment can be used to accommodate the electrode assembly 20, electrolyte and other components. Optionally, the shell 10 can be made of, but is not limited to, a metal or non-metal material. 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 which electrochemical reactions occur in the battery cell 7. The electrode assembly 20 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally provided between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet and the negative electrode sheet have portions with active materials that constitute a main body of the electrode assembly 20, and portions without active materials that each constitute a tab. The positive electrode tab and the negative electrode tab can be located together at one end of the main body or at opposite ends of the main body. During charging and discharging of the battery, the positive electrode active material and the negative electrode active material react with an electrolyte, and the tabs are connected to the electrode terminal 30 to form a current loop.

[0120] The wall portion 12 of the housing 10 is provided with a first recess 121 for accommodating the electrode terminal 30. After the electrode terminal 30 is provided on the wall portion 12 and electrically connected to the tab, a portion of the electrode terminal 30 is accommodated in the first recess 121. The wall portion 12 can be integrally formed with the first recess 121, 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 first recess 121 by a casting or injection molding process, etc.; or the first recess 121 can be machined on the wall portion 12 by a milling, turning, wire cutting or laser cutting process, etc.

[0121] The electrode lead-out hole 124 can facilitate the connection of the electrode terminal 30 to a bus bar or other conductive element. The wall portion 12 can be integrally formed with the electrode lead-out hole 124, or the electrode lead-out hole 124 can be machined on the wall portion 12 by a milling, turning, wire cutting or laser cutting process, etc.

[0122] The electrode terminal 30 can be arranged through 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 extends outside the housing 10 through the electrode lead-out hole 124.

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

[0124] The electrode terminal 30 can 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 inside the electrode lead-out hole 124.

[0125] The electrode lead-out hole 124 can facilitate the connection of the electrode terminal 30 to a bus bar or other conductive element, 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 portion 12 can be, but is not limited to, a circle, a rectangle, an ellipse, a triangle, or a trapezoid, etc., which can be selected according to the actual application environment. In an example, the projection shape of the first recess 121 along the thickness direction X of the wall portion 12 matches the projection shape of the partial electrode terminal 30 accommodated in the first recess 121 along the thickness direction X of the wall portion 12.

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

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

[0129] Exemplarily, a part of the electrode terminal 30 is arranged on the side of the wall portion 12 facing the accommodation cavity 11, and a part of the electrode terminal 30 is arranged on the side of the wall portion 12 facing away from the accommodation cavity 11, in other words, a part of the electrode terminal 30 is arranged inside the shell 10, and a part of the electrode terminal 30 is arranged outside the shell 10. The part of the electrode terminal 30 located inside the shell 10 is used to connect the tab, and the part of the electrode terminal 30 located outside the shell 10 is used to connect the bus bar or other conductive elements to realize the output or input of the electric energy of the battery monomer 7.

[0130] The wall portion 12 can 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 process, etc.; or the second recess 122 can be machined on the wall portion 12 by milling, turning, wire cutting or laser cutting process, etc.

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

[0132] The second recess 122 can be used to accommodate the part of the electrode terminal 30 located outside the shell 10, so as to reduce the occupancy of the electrode terminal 30 to the space outside the battery monomer 7, facilitate the reduction of the overall volume of the battery monomer 7, and further improve the energy density of the battery monomer 7.

[0133] In some embodiments, the projection of the second recess 122 along the thickness direction X of the wall portion 12 surrounds the 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 in the thickness direction X of the wall portion 12, so as to avoid interference between the first recess 121 and the second recess 122 to some extent, reduce the difficulty of setting the first recess 121 and the second recess 122, and reduce the risk of fracture caused by the local thickness of the wall portion 12 being too small and the structural strength being too low, and improve the reliability of the battery monomer 7.

[0135] In some embodiments, the projection 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 oval ring. The electrode terminal 30 can be limited to prevent 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 protrusion 123 protruding from the surface of the wall portion 12 facing away from the accommodation cavity 11, and the position of the protrusion 123 corresponds to the position of the first recess 121.

[0137] For example, the protrusion 123 can be connected to the surface of the wall portion 12 facing away from the accommodation cavity 11 by welding, riveting, or bonding, or can be integrally formed with the wall portion 12 by bending, casting, or injection molding. As an example, a part of the wall portion 12 is bent away from the accommodation cavity 11 to form the protrusion 123 on the side of the wall portion 12 facing away from the accommodation cavity 11 and the recess on the side of the wall portion 12 facing the accommodation cavity 11.

[0138] The above technical solution sets the protrusion 123 at the position of the first recess 121, which facilitates the increase of the thickness of the wall portion 12 at the position of the first recess 121, thereby improving the overall structural strength of the wall portion 12, reducing the risk of fracture caused by the local thickness of the wall portion 12 being too small and the structural strength being too low, and improving the reliability of the battery monomer 7.

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

[0140] Exemplarily, a part of the electrode terminals 30 are arranged on the side of the wall portion 12 facing the accommodating cavity 11, and a part of the electrode terminals 30 are arranged on the side of the wall portion 12 facing away from the accommodating cavity 11, in other words, a part of the electrode terminals 30 are arranged inside the housing 10, and a part of the electrode terminals 30 are arranged outside the housing 10. The part of the electrode terminals 30 arranged inside the housing 10 are used to connect the tabs, and the part of the electrode terminals 30 arranged outside the housing 10 are used to connect the bus bars or other conductive elements to realize the output or input of the electric energy of the battery cell 7. The part of the electrode terminals 30 arranged inside the housing 10 are provided with the third recess 31.

[0141] The electrode terminals 30 can be integrally formed with the third recess 31, 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 third recess 31 by casting or injection molding process, etc.; or the third recess 31 can be processed on the electrode terminals 30 by milling, turning, wire cutting or laser cutting process, etc.

[0142] Optionally, the projection shape of the third recess 31 along the thickness direction X of the wall portion 12 can be, but is not limited to, a circle, a rectangle, an ellipse, a triangle or a trapezoid, etc., which can 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 portion 12 matches the projection shape of the part of the convex portion 123 accommodated in the third recess 31 along the thickness direction X of the wall portion 12.

[0143] The third recess 31 of the above technical solution can be used to accommodate the convex portion 123 to reduce the size of the battery cell 7 in the thickness direction X of the wall portion 12, which is beneficial to reduce 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 comprises a sealing member 40, at least part of the sealing member 40 surrounds the electrode lead-out hole 124 and is clamped between the electrode terminal 30 and the bottom wall of the first recess 121 in the thickness direction X.

[0145] Exemplarily, at least part of the sealing member 40 surrounds the electrode lead-out hole 124 and is clamped between the electrode terminal 30 and the bottom wall of the first recess 121, which can be understood as that part of the sealing member 40 surrounds the electrode lead-out hole 124 and is clamped between the electrode terminal 30 and the bottom wall of the first recess 121, or the entire sealing member 40 surrounds the electrode lead-out hole 124 and is clamped between the electrode terminal 30 and the bottom wall of the first recess 121.

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

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

[0148] The sealing member 40 can be, but is not limited to, a block structure, a sheet structure or a columnar structure, etc., which can be selected according to the actual application environment. The sealing member 40 can be, but is not limited to, made of silicone rubber, fluorine rubber, polytetrafluoroethylene, epoxy resin or polyurethane, etc.

[0149] The sealing member 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 damage to the battery monomer 7 caused by the external water vapor or impurities entering the inside of the battery monomer 7 through the electrode lead-out hole 124. In addition, the sealing member 40 can be accommodated in the first recess 121, so as to reduce the occupation of the internal space of the battery monomer 7 by the sealing member 40, thereby effectively improving the energy density of the battery monomer 7.

[0150] In some embodiments, the electrode terminal 30 is provided through 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] For example, the terminal plate 33 is located on the side of the wall portion 12 away from the accommodation cavity 11, i.e. the terminal plate 33 is located outside the shell 10, and the terminal plate 33 serves as an external wiring part connected with the bus bar. The connecting portion 321 of the pole 32 serves as a part fixedly connected with the wall portion 12, and the limiting portion 322 of the pole 32 serves as an internal wiring part electrically connected with the first tab.

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

[0153] As an example, the pole column 32 and the terminal plate 33 are an integrally formed structure. On the one hand, the pole column 32 and the terminal plate 33 do not need to be connected through an additional connection process, simplifying the manufacturing process flow. At the same time, compared with connecting the pole column 32 and the terminal plate 33 through an additional connection process, the pole column 32 and the terminal plate 33 in an integrated structure have higher connection firmness between them.

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

[0155] As an example, the connecting portion 321 and the limiting portion 322 are an integrally formed structure. On the one hand, the connecting portion 321 and the limiting portion 322 do not need to be connected through an additional connection process, simplifying the manufacturing process flow. 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 integrated structure have higher connection firmness between them.

[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 greater 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 conducive to improving the flow area between the 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 monomer 7.

[0158] In some embodiments, the terminal plate 33 is provided with a through hole 331, and the pole column 32 penetrates 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 arranged at a substantially central position of the terminal plate 33, and a hole diameter of the through hole 331 is adapted to a diameter of the connecting portion 321 of the pole column 32. When the electrode terminal 30 is installed to the wall portion 12, the terminal plate 33 needs to be fixed to a side of the wall portion 12 facing away from the accommodation cavity 11, the connecting portion 321 of the pole column 32 extends out of the electrode lead-out hole 124 from a side of the wall portion 12 facing the accommodation cavity 11 to an outside of the shell 10, and the limiting portion 322 can abut against the side of the wall portion 12 facing the accommodation cavity 11, thereby limiting the pole column 32. The connecting portion 321 further extends into the through hole 331 of the terminal plate 33 after passing through the electrode lead-out hole 124, so as to fixedly connect the pole column 32 with the terminal plate 33, thereby fixing the electrode terminal 30 to the wall portion 12.

[0160] The technical solution described above can improve the contact area between the pole column 32 and the terminal plate 33, thereby facilitating to improve the connection firmness between the pole column 32 and the terminal plate 33, and further improving the reliability of the electrode terminal 30 as a whole.

[0161] In some embodiments, the battery monomer 7 further comprises a first insulating member 50 arranged at a side of the wall portion 12 facing away from the accommodation cavity 11, the first insulating member 50 being used to insulate and separate the electrode terminal 30 from the wall portion 12, so as to further improve the reliability of the battery monomer 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 comprises a first segment and a second segment connected in series, the first segment being connected between the terminal plate 33 and the wall portion 12, and the second segment extending along a thickness direction X of the wall portion 12 from an end of the first segment away from the pole column 32 and being connected to a side surface of the terminal plate 33 away from the pole column 32. The second segment 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 with 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 monomer 7 further comprises a second insulating member 60 arranged at a side of the wall portion 12 facing the accommodation cavity 11, the second insulating member 60 being used to insulate and separate the electrode terminal 30 from the wall portion 12, so as to further improve the reliability of the battery monomer 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 insulation member 60 is connected with the sealing member 40, which not only improves the stability of the sealing member 40, but also further improves the sealing effect of the sealing member 40.

[0166] In some embodiments, the sealing member 40 comprises a first portion 41 and a second portion 42 connected with each other, the first portion 41 is clamped between the inner wall of the electrode lead-out hole 124 and the connecting portion 321, and the second portion 42 is clamped between the limiting portion 322 and the bottom wall of the first recess 121.

[0167] The first portion 41 can be detachably connected with the second portion 42, or can be integrally arranged on the second portion 42. The first portion 41 can be directly connected with the second portion 42, or can be limited on the second portion 42 through other components. As an example, the connection mode of the first portion 41 and the second portion 42 can be, but is not limited to, bolt connection, riveting, bonding or clamping, etc.

[0168] As an example, the first portion 41 and the second portion 42 are integrally formed. On the one hand, the first portion 41 and the second portion 42 do not need to be connected through an additional connection process, which simplifies the manufacturing process flow. At the same time, compared with connecting the first portion 41 and the second portion 42 through an additional connection process, the first portion 41 and the second portion 42 in an integral structure have higher connection firmness.

[0169] Optionally, the first portion 41 and the second portion 42 can be made of the same material to simplify the preparation process and reduce costs.

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

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

[0172] FIG. 7 is a top view of another battery cell according to some embodiments of the present application, and FIG. 8 is a cross-sectional view of FIG. 7 along line B-B.

[0173] Continuing to refer to FIGS. 7-8, in some embodiments, the sealing member 40 further comprises 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 clamped between the terminal plate 33 and the surface of the wall portion 12 facing away from the accommodating cavity 11.

[0174] The third part 43 can be detachably connected to the first part 41, or integrally arranged on the first part 41. The first part 41 can be directly connected to the first part 41, or limited on the first part 41 by other components. As an example, the connection mode of the first part 41 to the first part 41 can be, but is not limited to, bolt connection, riveting, bonding or clamping, etc.

[0175] As an example, the third part 43 and the first part 41 are integrally formed. On the one hand, the third part 43 and the first part 41 do not need to be connected through an additional connection process, simplifying the manufacturing process flow. 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 integrated structure have higher connection firmness.

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

[0177] Optionally, the first part 41, the second part 42 and the third part 43 can be made of different materials to make targeted selection according to different structural characteristics of the electrode lead-out hole 124, the limiting part 322 and the terminal plate 33, and improve the adaptability of the sealing piece 40.

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

[0179] In some embodiments, the first dimension H1 of the wall part 12 in the thickness direction X of itself and the second dimension H2 of the first recess 121 in the thickness direction X satisfy the relationship: 0

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

[0181] As an example, the ratio H2 / H1 between the second dimension H2 and the first dimension H1 can 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 greater the ratio H2 / H1 between the second size H2 and the first size H1, the greater the proportion of the first recess 121 on the wall portion 12 in the thickness direction X of the wall portion 12, and the worse the structural consistency of the wall portion 12 as a whole. The smaller the ratio H2 / H1 between the second size H2 and the first size H1, the fewer the electrode terminals 30 that can be accommodated by the first recess 121.

[0183] In this way, by setting the first size H1 of the wall portion 12 in the thickness direction X thereof and the second size H2 of the first recess 121 in the thickness direction X thereof to satisfy the above relationship, the above technical solution can reduce the occupancy rate of the electrode terminals 30 on the internal space of the battery monomer 7, thereby improving the energy density of the battery monomer 7, while taking into account the structural consistency of the wall portion 12 as a whole.

[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 can 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 size H1 of the wall portion 12 in the thickness direction X thereof satisfies the relationship: 1mm≤H1≤5mm. As an example, the first size H1 can be, but is not limited to, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm.

[0187] Further, the first size H1 of the wall portion 12 in the thickness direction X thereof satisfies the relationship: 2mm≤H1≤3mm. As an example, the first size H1 can 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.

[0188] In some embodiments, the second size H2 of the first recess 121 in the thickness direction X thereof satisfies the relationship: 0.1mm≤H2≤2mm. As an example, the second size H2 can be, but is not limited to, 0.1mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm, 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2mm.

[0189] Further, the first recess 121 has a second dimension H2 in the thickness direction X that satisfies the relationship: 0.3 mm≤H2≤1 mm. As an example, the second dimension H2 can 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, 1 mm.

[0190] In some embodiments, the electrode terminal 30 located in the accommodation cavity 11 has a third dimension H3 in the thickness direction X that satisfies the relationship: 1.5 mm≤H3≤5 mm.

[0191] As an example, the third dimension H3 can 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.

[0192] It can be understood that the smaller the third dimension H3 of the electrode terminal 30 located in the accommodation cavity 11 in the thickness direction X, the smaller the occupancy rate of the electrode terminal 30 to the internal space of the battery monomer 7, and the lower the structural strength and connection firmness of the electrode terminal 30; the larger the third dimension H3 of the electrode terminal 30 located in the accommodation cavity 11 in the thickness direction X, the larger the occupancy rate of the electrode terminal 30 to the internal space of the battery monomer 7, and the higher the structural strength and connection firmness of the electrode terminal 30.

[0193] Thus, the above technical solution sets the third dimension H3 of the electrode terminal 30 located in the accommodation cavity 11 in the thickness direction X within the above range, which can reduce the occupancy rate of the electrode terminal 30 to the internal space of the battery monomer 7 while ensuring the structural strength and connection firmness of the electrode terminal 30, thereby balancing the energy density and reliability of the battery monomer 7.

[0194] Further, the third dimension H3 satisfies the relationship: 2 mm≤H3≤3 mm. As an example, the third dimension H3 can be, but is not limited to, 2 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3 mm, etc.

[0195] In some embodiments, the shell 10 includes a shell body 10a having an opening and the accommodation cavity 11, and an end cover 10b configured to cover the opening, the end cover 10b being configured as the wall portion 12.

[0196] The end cover 10b is configured to cover the opening of the housing 10a to seal the internal environment of the battery cell 7 from the external environment. Optionally, the end cover 10b can be shaped to fit the housing 10a. Optionally, the end cover 10b can be made of a material with certain hardness and strength, such as aluminum alloy, so that the end cover 10b is less likely to deform under pressure and impact, and the battery cell 7 can have higher structural strength and reliability. Functional components such as the terminal group can be provided on the end cover 10b. In some embodiments, the end cover 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 value. The material of the end cover 10b can be various, such as, but not limited to, metal or non-metal materials. For example, the metal material can be copper, aluminum, stainless steel, etc., and the non-metal material can be polyethylene, polypropylene, polyvinyl chloride, etc.

[0197] The housing 10a is configured to fit the end cover 10b to form the internal environment of the battery cell 7. The internal environment can be configured to accommodate the electrode assembly 20, the electrolyte, and other components. The housing 10a and the end cover 10b can be separate components, and the housing 10a can be provided with an opening. The end cover 10b can be configured to cover the opening to form the internal environment of the battery cell 7. Alternatively, the end cover 10b and the housing 10a can be integrated. Specifically, the end cover 10b and the housing 10a can form a common connection surface before other components are placed in the housing. When it is necessary to seal the internal environment of the housing 10a, the end cover 10b can be configured to cover the housing 10a. The housing 10a can have various shapes and sizes, such as a rectangular shape, a cylindrical shape, a hexagonal shape, etc. Specifically, the shape of the housing 10a can be determined according to the specific shape and size of the electrode assembly 20. The material of the housing 10a can be various, such as, but not limited to, metal or non-metal materials. For example, the metal material can be copper, aluminum, stainless steel, etc., and the non-metal material can be polyethylene, polypropylene, polyvinyl chloride, etc.

[0198] Optionally, the end cover 10b can be detachably connected to the housing 10a, or can be integrally provided on the housing 10a. The end cover 10b can be directly connected to the housing 10a, or can be limited on the housing 10a by other components. As an example, the connection mode of the end cover 10b and the housing 10a can be, but is not limited to, welding, riveting, or bonding, etc.

[0199] According to some embodiments of the present application, the present application also provides a battery comprising the battery cell 7 of any of the above embodiments.

[0200] According to some embodiments of the present application, the present application also provides a battery cell 7, which is used to provide electric energy.

[0201] In order to better understand the battery cell 7 provided by the embodiments of the present application, based on the same inventive concept, the above-mentioned battery cell 7 in actual application is described.

[0202] The embodiments of the present application provide a battery cell 7, which comprises a shell 10, an electrode assembly 20, an electrode terminal 30 and a sealing member 40, and the shell 10 is internally provided with a containing cavity 11. The shell 10 comprises a wall portion 12, the wall portion 12 is provided with 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 containing 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 arranged in the containing cavity 11 and comprises a tab, the electrode terminal 30 is arranged on 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 clamped between the electrode terminal 30 and the bottom wall of the first recess 121.

[0203] The first recess 121 of the above technical solution can be used to accommodate the electrode terminal 30 and the sealing member 40, so as to reduce the occupancy rate of the electrode terminal 30 and the sealing member 40 to the internal space of the battery cell 7, so that more space can be left in the battery cell 7 to arrange the electrode assembly 20, thereby effectively improving the energy density of the battery cell 7.

[0204] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0205] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; 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 be covered in the scope of the claims and the description of the present application. Especially, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, comprising: a housing having an accommodating cavity therein, the housing including 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 accommodating cavity, 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; An electrode terminal is provided 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, wherein: The wall portion further has a second recessed portion, which is recessed relative to a surface of the wall portion 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, wherein: A projection of the second recess along the thickness direction of the wall portion surrounds a projection of the first recess along the thickness direction.

4. The battery cell according to any one of claims 1 to 3, wherein: 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, wherein: The electrode terminal has a third recessed portion that 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.

6. The battery cell according to any one of claims 1 to 5, wherein: The battery cell further includes a sealing member. In the thickness direction, at least a portion of the sealing member surrounds the electrode lead-out hole and is sandwiched between the electrode terminal and a bottom wall of the first recess.

7. The battery cell according to claim 6, wherein: 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, wherein: 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, wherein: The sealing member includes a first portion and a second portion 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, wherein: 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 any one of claims 1 to 10, wherein: A first dimension H1 of the wall portion in its own thickness direction and a second dimension H2 of the first recess in the thickness direction satisfy the relationship: 0<H2 / H1≤0.

5.

12. The battery cell according to any one of claims 1 to 11, wherein: 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, wherein: The housing comprises a shell and an end cover, the shell having 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 comprising a plurality of battery cells according to any one of claims 1 to 13.

15. An electrical device comprising the battery cell according to any one of claims 1 to 13, wherein the battery cell is used to provide electrical energy.

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