Battery cell, battery, and electrical apparatus

Abstract

A battery cell (20), a battery (100), and an electrical apparatus. A casing (1) of the battery cell (20) has an accommodating cavity, an electrode assembly (2) being disposed in the accommodating cavity and comprising a first tab (21), and an electrode terminal (3) being disposed on the casing (1) and being electrically connected to the first tab (21). The electrode terminal (3) is provided with a recessed portion (31), a cover plate (4) is provided on the side of the electrode terminal (3) away from the electrode assembly (2) and covers the recessed portion (31), and a positioning structure (32) provided along the periphery of the recessed portion (31) is disposed on the side of the electrode terminal (3) away from the electrode assembly (2). Because the positioning structure (32) provided along the periphery of the recessed portion (31) is disposed on the side of the electrode terminal (3) away from the electrode assembly (2), the position of the cover plate (4) can be determined by means of the positioning structure (32) during the process of assembling the battery cell (20) so as to learn the concentricity of the cover plate (4) and the recessed portion (31), thereby facilitating improving the concentricity of the cover plate (4) and the recessed portion (31), improving the connection effect of the cover plate (4) and the electrode terminal (3), and further improving the blocking effect of the cover plate (4) for the recessed portion (31), helping to increase the yield in a production process of the battery cell (20).

Description

Battery cells, batteries and electrical devices

[0001] Cross-reference of related applications

[0002] This application claims priority to Chinese Patent Application No. 202421187039.4, filed on May 28, 2024, entitled “Battery Cell, Battery and Electrical Device”, the entire contents of which are incorporated herein by reference. Technical Field

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

[0004] Batteries have advantages such as high energy density and high power density, and are widely used in electronic devices and transportation, such as mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships and power tools.

[0005] With the increasingly widespread application of batteries, the market demand for batteries is growing. Improving the yield rate in the battery production process is receiving increasing attention from those skilled in the art.

[0006] Summary of the Invention

[0007] In view of the above problems, this application provides a battery cell, a battery, and an electrical device, which helps to improve the yield rate of production.

[0008] In a first aspect, some embodiments of this application provide a battery cell, which includes a housing, an electrode assembly, an electrode terminal, and a cover plate. The housing has a receiving cavity; the electrode assembly is disposed in the receiving cavity and includes a first electrode tab; the electrode terminal is disposed in the housing and electrically connected to the first electrode tab, and the electrode terminal has a recess; the cover plate is disposed on the side of the electrode terminal away from the electrode assembly and covers the recess, wherein the side of the electrode terminal away from the electrode assembly is provided with a positioning structure disposed along the outer periphery of the recess.

[0009] Because the electrode terminal is provided with a positioning structure along the outer periphery of the recess on the side away from the electrode assembly, the position of the cover plate can be determined by the positioning structure during the assembly of the battery cell, so as to know the concentricity of the cover plate and the recess. This helps to improve the concentricity of the cover plate and the recess, improve the connection effect between the cover plate and the electrode terminal, and thus improve the sealing effect of the cover plate on the recess, which helps to improve the yield rate of the battery cell in the production process.

[0010] According to some embodiments of this application, the positioning structure of the battery cell is configured to be concentric with the recess.

[0011] By setting the positioning structure concentrically with the recess, the axis of the recess can be determined by measuring the axis of the positioning structure, and the concentricity between the recess and the cover plate can be determined by detecting the concentricity between the positioning structure and the cover plate, making the detection convenient.

[0012] According to some embodiments of this application, the positioning structure of the battery cell includes a protrusion disposed along the outer periphery of the recess.

[0013] According to some embodiments of this application, the battery cell provided has a protrusion that does not extend beyond the cover plate along the axial direction of the recess, away from the electrode assembly.

[0014] By ensuring that the end of the protrusion away from the electrode assembly in the axial direction of the recess does not extend beyond the cover plate, the protrusion is less likely to interfere with the connection between the cover plate and external electrical equipment.

[0015] According to some embodiments of this application, the positioning structure of the battery cell includes a first groove, which is disposed along the outer periphery of the recess.

[0016] According to some embodiments of the present application, the battery cell has a first groove with an opening facing away from the electrode assembly, and the size of the opening along the radial direction of the groove is A, 0.1mm≤A≤0.8mm.

[0017] By setting the opening of the first groove to face away from the electrode assembly, the assembly personnel can identify the first groove from the outside of the electrode terminal through the equipment, which facilitates the measurement of the axis of the positioning structure.

[0018] According to some embodiments of the present application, the depth of the first groove in the axial direction of the recess is B, 0.1mm≤B≤0.8mm, so that the first groove has a suitable depth, which not only allows the first groove to form a more obvious imprint on the outside of the electrode terminal, making it easier for assembly personnel to identify through equipment, but also reduces the impact of the first groove on the electrode terminal structure, which is beneficial to maintaining the structural strength of the electrode terminal.

[0019] According to some embodiments of this application, the battery cell positioning structure includes a plurality of positioning portions circumferentially spaced along the recess. By circumferentially spaced along the recess, the positioning structure formed by the plurality of positioning portions is coaxial with the recess. Exemplarily, the plurality of positioning portions may be a plurality of arc-shaped first grooves or a plurality of arc-shaped protrusions.

[0020] According to some embodiments of this application, the positioning structure of the battery cell is an annular structure surrounding the outer periphery of the recess, such that the positioning structure is coaxially sleeved on the outside of the recess.

[0021] According to some embodiments of the present application, the minimum distance C between the positioning structure and the cover plate along the radial direction of the recess is 2mm≤C≤12mm. This not only leaves enough space in the area near the recess to place the formation probe, but also prevents the positioning structure from getting too close to the edge of the electrode terminal, making it easier for the image recognition device to distinguish the positioning structure from the edge of the electrode terminal.

[0022] According to some embodiments of this application, the battery cell includes a housing and an end cap. The housing has an opening, and the end cap closes the opening. The housing includes an end wall disposed opposite to the end cap. Electrode terminals are disposed on the end wall, such that when the battery cell is connected to an electrical device, the electrode terminals can achieve electrical connection between the battery cell and the electrical device by firmly abutting against the power input terminal of the electrical device.

[0023] According to some embodiments of this application, the battery cell includes an electrode assembly comprising a second electrode with a polarity opposite to that of the first electrode, the second electrode being electrically connected to an end cap.

[0024] According to some embodiments of the present application, the battery cell has a cover plate welded to the electrode terminals. Welding allows the materials of the cover plate and the electrode terminals to be fused together, which not only improves the connection strength between the cover plate and the electrode terminals but also improves the sealing performance of the cover plate over the recess.

[0025] Secondly, some embodiments of this application provide a battery comprising a single battery cell provided by any of the above-described technical solutions.

[0026] Thirdly, some embodiments of this application provide an electrical device that includes the battery provided by the above-described technical solution, the battery being used to provide electrical energy.

[0027] The technical solutions provided by the embodiments of this disclosure have at least the following beneficial effects:

[0028] Some embodiments of this application provide a battery cell including a casing, an electrode assembly, electrode terminals, and a cover plate. The casing has a receiving cavity, the electrode assembly is disposed within the receiving cavity and includes a first tab, the electrode terminals are disposed on the casing and electrically connected to the first tab, and the electrode terminals have recesses. The cover plate is disposed on the side of the electrode terminals away from the electrode assembly and covers the recesses. A positioning structure is provided on the side of the electrode terminals away from the electrode assembly, along the outer periphery of the recesses. Because the positioning structure is provided on the side of the electrode terminals away from the electrode assembly, the position of the cover plate can be determined during the assembly of the battery cell to determine the concentricity of the cover plate and the recesses. This improves the concentricity of the cover plate and the recesses, enhances the connection effect between the cover plate and the electrode terminals, and further improves the sealing effect of the cover plate on the recesses, thus contributing to a higher yield rate in the battery cell production process.

[0029] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0030] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0031] Figure 1 is a schematic diagram of a vehicle provided in some embodiments of this application;

[0032] Figure 2 is a schematic diagram showing the disassembled battery provided in some embodiments of this application;

[0033] Figure 3 is a top view of a battery cell provided in some embodiments of this application;

[0034] Figure 4 is a cross-sectional view of section GG in Figure 3 in some embodiments of this application;

[0035] Figure 5 is an enlarged view of point F in Figure 4 in some embodiments of this application;

[0036] Figure 6 is an enlarged view of point F in Figure 4 in some other embodiments of this application;

[0037] Figure 7 is an enlarged view of H in Figure 3 in some embodiments of this application.

[0038] In the attached drawings: 1. Outer shell; 11. Housing; 111. End wall; 12. End cap; 2. Electrode assembly; 21. First tab; 22. Second tab; 3. Electrode terminal; 31. Recess; 32. Positioning structure; 321. Protrusion; 322. First groove; 323. Positioning part; 4. Cover plate; 10. Housing; 101. First housing; 102. Second housing; 20. Battery cell; 1000. Vehicle; 100. Battery; 200. Controller; 300. Motor. Detailed Implementation

[0039] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0040] It should be noted that, unless otherwise stated, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by those skilled in the art to which the embodiments of this application pertain.

[0041] In the description of the embodiments of this application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0042] Furthermore, technical terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of the embodiments of this application, "a plurality of" means two or more, unless otherwise explicitly defined.

[0043] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0044] In the description of the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0045] Currently, judging from market trends, the application of batteries is becoming increasingly widespread. Batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace, among other fields.

[0046] The battery mentioned in the embodiments of this application includes one or more battery modules, and a battery module refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity.

[0047] In this embodiment of the application, the battery cell can be a secondary battery cell, which refers to a battery cell that can be used again after being discharged by recharging to activate the active materials.

[0048] 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-metal hydride battery cell, a nickel-cadmium battery cell, a lead-acid battery cell, etc., but the embodiments of this application are not limited to this.

[0049] A single battery cell typically includes an electrode assembly. The electrode assembly consists of a positive electrode and a negative electrode. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes.

[0050] In some embodiments, the electrode assembly further includes an isolator disposed between the positive and negative electrodes, which can prevent short circuits between the positive and negative electrodes while allowing active ions to pass through.

[0051] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a layer of positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0052] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material layer is disposed on either or both of the two opposite surfaces of the positive current collector.

[0053] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, stainless steel, copper, aluminum, nickel, silver-coated aluminum, silver-coated stainless steel, carbon electrodes, carbon, nickel, or titanium can be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum 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.).

[0054] 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 phosphates, lithium transition metal oxides, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphates include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxides include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.80 Co 0.15 Al 0.05 At least one of O2 and its modified compounds.

[0055] In some embodiments, the positive electrode can be made of foamed carbon or foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, or foamed alloys, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, lithium source material, potassium metal, or sodium metal can also be filled and / or deposited within the foamed metal, where the lithium source material is lithium metal and / or lithium-rich material.

[0056] In some embodiments, the negative electrode may be a negative electrode sheet, which may include a negative electrode current collector and a layer of negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0057] As an example, the negative electrode current collector can be a metal foil, foamed metal, foamed carbon, or a composite current collector. For example, as a metal foil, stainless steel, copper, aluminum, nickel, silver-treated aluminum, silver-treated stainless steel, carbon electrodes, carbon, nickel, or titanium can be used. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, or foamed alloys. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (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.).

[0058] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0059] In some embodiments, the negative electrode can be made of foamed carbon or foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, or foamed alloy, etc. When foamed metal is used as the negative electrode sheet, the surface of the foamed metal may or may not have a negative electrode active material.

[0060] As an example, lithium source material, potassium metal or sodium metal may also be filled or deposited in the negative electrode current collector, wherein the lithium source material is lithium metal and / or lithium-rich material.

[0061] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0062] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0063] In some embodiments, the separator is a separator membrane. This application does not impose any particular limitation on the type of separator membrane; any known porous separator membrane with good chemical and mechanical stability can be selected.

[0064] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separator can be a separate component located between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes.

[0065] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrode plates, serving both to transport ions and to isolate the positive and negative electrodes.

[0066] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not impose specific limitations on the type of electrolyte; it can be selected according to requirements. The electrolyte can be liquid, gel, or solid.

[0067] In some embodiments, the liquid electrolyte includes an electrolyte salt and a solvent.

[0068] In some embodiments, the electrolyte salt may be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0069] In some embodiments, the solvent may be selected from at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0070] Gel electrolytes consist of a polymer-based electrolyte backbone network combined with an ionic liquid—lithium salt.

[0071] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0072] As an example, polymer solid electrolytes can be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0073] As an example, inorganic solid electrolytes can be one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphorus sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0074] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0075] In some embodiments, the electrode assembly is a wound structure. The positive electrode and the negative electrode are wound into a wound structure.

[0076] In some implementations, the electrode assembly is a stacked structure.

[0077] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0078] As an example, multiple positive electrode plates can be provided, and negative electrode plates can be folded to form multiple stacked folded segments, with a positive electrode plate sandwiched between adjacent folded segments.

[0079] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0080] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0081] As an example, the separators can be continuously arranged, either by folding or rolling between any adjacent positive or negative electrode plates.

[0082] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0083] In some embodiments, the electrode assembly is provided with tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0084] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing may be made of steel, aluminum, plastic (such as polypropylene), composite metal (such as copper-aluminum composite), or aluminum-plastic film, etc.

[0085] As an example, a battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries.

[0086] The battery mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity.

[0087] In some embodiments, the battery can be a battery module, and when there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0088] In some embodiments, the battery can be a battery pack, which includes a housing and individual battery cells, with the individual battery cells or battery modules housed within the housing.

[0089] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0090] In some embodiments, the battery can be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0091] In existing technologies, through holes are typically provided on the electrode terminals for electrolyte filling of battery cells. After electrolyte filling, a cover plate is usually installed to cover the through holes of the electrode terminals, and the cover plate is usually connected to the electrode terminals by welding. However, during the process of covering the through holes, the cover plate is prone to misalignment. This can lead to quality problems in the welding of the cover plate, reduce the connection effect between the cover plate and the electrode terminals, affect the production quality of battery cells, and reduce the yield rate of battery cell production.

[0092] To improve the yield rate of battery cells, some embodiments of this application provide a battery cell including a casing, an electrode assembly, electrode terminals, and a cover plate. The casing has a receiving cavity, the electrode assembly is disposed within the receiving cavity and includes a first tab, the electrode terminals are disposed on the casing and electrically connected to the first tab, and the electrode terminals have recesses. The cover plate is disposed on the side of the electrode terminals away from the electrode assembly and covers the recesses. A positioning structure is provided on the side of the electrode terminals away from the electrode assembly, along the outer periphery of the recesses. Because the positioning structure is provided on the side of the electrode terminals away from the electrode assembly, the position of the cover plate can be determined during the assembly of the battery cell to determine the concentricity of the cover plate and the recesses. This improves the concentricity of the cover plate and the recesses, enhances the connection effect between the cover plate and the electrode terminals, and thus improves the sealing effect of the cover plate on the recesses, contributing to a higher yield rate in the battery cell production process.

[0093] The battery cell described in this application is applicable to batteries and electrical devices that use batteries. This battery cell can be used, but is not limited to, batteries, and can also be used in products such as vehicles, aircraft, ships, electronic devices, and power tools, thereby improving the reliability of these products.

[0094] Electrical devices can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.

[0095] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to an embodiment of this application.

[0096] Please refer to Figure 1, which is a structural schematic diagram of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery 100 is disposed inside the vehicle 1000, and the battery 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery 100 can be used to power the vehicle 1000; for example, the battery 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during startup, navigation, and driving.

[0097] In some embodiments of this application, the battery 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0098] Please refer to Figure 2, which is an exploded view of a battery 100 provided in some embodiments of this application. The battery 100 includes a housing 10 and individual battery cells 20, with the individual battery cells 20 housed within the housing 10. The housing 10 provides space for the individual battery cells 20. There can be multiple individual battery cells 20 in the battery 100, which can be connected in series, parallel, or a combination thereof. A combination thereof means that some of the individual battery cells 20 are connected in series and others in parallel. Multiple individual battery cells 20 can be directly connected in series, parallel, or a combination thereof, and then the entire assembly of the multiple individual battery cells 20 is housed within the housing 10. Alternatively, the battery 100 can also be composed of multiple individual battery cells 20 first connected in series, parallel, or a combination thereof to form a battery module, and then these battery modules are connected in series, parallel, or a combination thereof to form a whole, which is then housed within the housing 10.

[0099] The housing 10 may include a first housing 101 and a second housing 102, which overlap each other to define a placement space for accommodating the battery cell 20. The first housing 101 and the second housing 102 may have various shapes, such as cuboids or cylinders. The first housing 101 may be a hollow structure with one open side, and the second housing 102 may also be a hollow structure with one open side. When the open side of the second housing 102 overlaps the open side of the first housing 101, a housing 10 with a placement space is formed.

[0100] The battery 100 may also include other structures, for example, the battery 100 may also include a busbar for realizing electrical connection between multiple battery cells 20.

[0101] Each battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited to these. The battery cell 20 can be cylindrical, flat, cuboid, or other shapes.

[0102] Some embodiments of this application provide a battery cell 20, as shown in Figures 3 and 4. The battery cell 20 includes a housing 1, an electrode assembly 2, an electrode terminal 3, and a cover plate 4. The housing 1 has a receiving cavity. The electrode assembly 2 is disposed in the receiving cavity and includes a first tab 21. The electrode terminal 3 is disposed on the housing 1 and electrically connected to the first tab 21. The electrode terminal 3 has a recess 31. The cover plate 4 is disposed on the side of the electrode terminal 3 away from the electrode assembly 2 and covers the recess 31. The side of the electrode terminal 3 away from the electrode assembly 2 is provided with a positioning structure 32 disposed along the outer periphery of the recess 31.

[0103] The outer casing 1 can be a wall structure disposed on the outer periphery of the battery cell 20, which can form a cavity for accommodating other components of the battery cell 20, such as the electrode assembly 2, and the electrolyte. The electrode assembly 2, as a component housed in the outer casing 1, is in contact with the electrolyte, and active ions (e.g., lithium ions) can be conducted between the electrode assembly 2 and the electrolyte. The outer casing 1 includes an end cap 12 and a housing 11. The housing 11 forms a cavity with an opening, and the end cap 12 seals the opening, making the cavity a sealed cavity for accommodating other components of the battery cell 20 and the electrolyte.

[0104] The electrode assembly 2 includes a positive electrode, a negative electrode, and a separator stacked together. The electrode assembly 2 is disposed within a receiving cavity and immersed in an electrolyte. During the charging and discharging process of the battery cell 20, active ions (e.g., lithium ions) are inserted and extracted back and forth between the positive and negative electrode. The first tab 21 can be a component of the positive or negative electrode used to draw current outward.

[0105] The electrode terminal 3 can be a connection terminal disposed on the housing 1, which is electrically connected to the first tab 21 of the electrode assembly 2 and protrudes outward from the housing 1. The electrode terminal 3 is used for electrical connection with external electrical equipment to deliver electrical energy to the external electrical equipment. The electrode terminal 3 includes, but is not limited to, a cylindrical structure, and can also be other shapes such as a prism structure.

[0106] The recess 31 can be a recessed structure provided on the electrode terminal 3, which is formed by recessing inward from the outer end face of the electrode terminal 3 away from the electrode assembly 2. Exemplarily, the recess 31 may or may not be connected to the receiving cavity. If the recess 31 is connected to the receiving cavity, the recess 31 forms a through hole that connects the receiving cavity to the outside, facilitating the injection of electrolyte into the receiving cavity through the recess 31.

[0107] The cover plate 4 can be a plate-like structure used to cover the recess 31 of the electrode terminal 3. By providing the cover plate 4 on the side of the electrode terminal 3 away from the electrode assembly 2 and covering the recess 31, the cover plate 4 can close the opening of the recess 31.

[0108] The positioning structure 32 can be a structure provided on the electrode terminal 3 for positioning the cover plate 4. By providing the positioning structure 32 on the side of the electrode terminal 3 away from the electrode assembly 2 and along the outer periphery of the recess 31, the position of the cover plate 4 can be determined by the positioning structure 32 to know the concentricity of the cover plate 4 and the recess 31.

[0109] For example, the positioning structure 32 can be a structure that protrudes from the outer end face of the electrode terminal 3 away from the outer end face of the electrode assembly 2, or it can be a structure that is recessed inward from the outer end face of the electrode terminal 3 away from the outer end face of the electrode assembly 2.

[0110] In the above structure, since the electrode terminal 3 is provided with a positioning structure 32 along the outer periphery of the recess 31 on the side away from the electrode assembly 2, the position of the cover plate 4 can be determined by the positioning structure 32 during the assembly of the battery cell 20 so as to know the concentricity of the cover plate 4 and the recess 31. This is beneficial to improve the concentricity of the cover plate 4 and the recess 31, improve the connection effect between the cover plate 4 and the electrode terminal 3, and thus improve the sealing effect of the cover plate 4 on the recess 31, which helps to improve the yield rate of the battery cell 20 in the production process.

[0111] In some embodiments, the electrode terminal 3 may be made of aluminum or aluminum alloy, and the cover plate 4 may be made of the same material as the electrode terminal 3, so that the cover plate 4 can be firmly connected to the electrode terminal 3 by welding.

[0112] In some embodiments, the positioning structure 32 is configured to be concentric with the recess 31.

[0113] By setting the positioning structure 32 and the recess 31 concentrically, the axis of the recess 31 can be known by measuring the axis of the positioning structure 32, and the concentricity of the recess 31 and the cover plate 4 can be known by detecting the concentricity of the positioning structure 32 and the cover plate 4, making the detection convenient.

[0114] In some embodiments, as shown in FIG5, the positioning structure 32 includes a protrusion 321, which is disposed along the outer periphery of the recess 31.

[0115] The protrusion 321 can be a structure that protrudes outward from the outer end face of the electrode terminal 3 away from the electrode assembly 2. The protrusion 321 is arranged along the outer periphery of the recess 31. The protrusion 321 can be a ring structure that extends around the outer periphery of the recess 31 in the circumferential direction; or the protrusion 321 can be a plurality of arc-shaped structures arranged at intervals, with the plurality of arc-shaped structures arranged at intervals along the circumferential direction of the recess 31 on the outer periphery of the recess 31, and each arc-shaped structure extending in the circumferential direction of the recess 31.

[0116] For example, the protrusion 321 can be manufactured simultaneously with the electrode terminal 3 using an integral forming process such as stamping.

[0117] In some embodiments, along the axial direction of the recess 31, the end of the protrusion 321 away from the electrode assembly 2 does not extend beyond the cover plate 4.

[0118] By ensuring that the end of the protrusion 321 that is axially away from the electrode assembly 2 in the recess 31 does not extend beyond the cover plate 4, the protrusion 321 is less likely to interfere with the connection between the cover plate 4 and the external electrical equipment.

[0119] In some embodiments, the positioning structure 32 includes a first groove 322, which is disposed along the outer periphery of the recess 31.

[0120] The first groove 322 can be a groove structure on the electrode terminal 3, which is formed by recessing inward from the side of the electrode terminal 3 away from the electrode assembly 2. The first groove 322 is provided along the outer periphery of the recess 31. The first groove 322 can be a ring structure that extends around the outer periphery of the recess 31 in the circumferential direction; or the first groove 322 can be a plurality of arc-shaped structures arranged at intervals, which are arranged at intervals along the circumferential direction of the recess 31 on the outer periphery of the recess 31, and each arc-shaped structure extends along the circumferential direction of the recess 31.

[0121] For example, the first groove 322 can be formed on the side of the electrode terminal 3 away from the electrode assembly 2 by processing methods such as milling and cutting to remove material. In some embodiments, the first groove 322 can be formed on the side of the electrode terminal 3 away from the electrode assembly 2 by laser grooving.

[0122] In some embodiments, as shown in FIG6, the first groove 322 has an opening facing away from the electrode assembly 2, and the size of the opening along the radial direction of the groove 31 is A, 0.1mm≤A≤0.8mm.

[0123] By setting the opening of the first groove 322 to face away from the electrode assembly 2, the assembly personnel can identify the first groove 322 from the outside of the electrode terminal 3 through the equipment, which facilitates the measurement of the axis of the positioning structure 32.

[0124] By setting the radial dimension A of the opening of the electrode assembly 2 in the recess 31 to 0.1mm≤A≤0.8mm, the first groove 322 has a suitable width, which not only makes the first groove 322 easier for assembly personnel to identify through the equipment, but also reduces the impact of the first groove 322 on the structure of the electrode terminal 3, which is beneficial to maintaining the structural strength of the electrode terminal 3.

[0125] The radial dimension A of the opening of the electrode assembly 2 in the recess 31 is set to be 0.3mm ≤ A ≤ 0.5mm. For example, A can be set to 0.3mm, 0.4mm or 0.5mm, which not only allows the first groove 322 to form a more obvious imprint on the outside of the electrode terminal 3, making it easier for assembly personnel to identify through the equipment, but also reduces the impact of the first groove 322 on the structure of the electrode terminal 3, which is beneficial to maintaining the structural strength of the electrode terminal 3.

[0126] In some embodiments, the depth of the first groove 322 in the axial direction of the recess 31 is B, where 0.1mm≤B≤0.8mm.

[0127] By setting the depth B of the first groove 322 in the axial direction of the recess 31 to a range of 0.1mm≤B≤0.8mm, the first groove 322 has a suitable depth. This not only allows the first groove 322 to form a more obvious imprint on the outside of the electrode terminal 3, making it easier for assembly personnel to identify through the equipment, but also reduces the impact of the first groove 322 on the structure of the electrode terminal 3, which is beneficial to maintaining the structural strength of the electrode terminal 3.

[0128] The depth B of the first groove 322 in the axial direction of the recess 31 is set to be 0.3mm ≤ B ≤ 0.5mm. For example, B can be set to 0.3mm, 0.4mm or 0.5mm, which not only allows the first groove 322 to form a more obvious imprint on the outside of the electrode terminal 3, making it easier for assembly personnel to identify through the equipment, but also reduces the impact of the first groove 322 on the structure of the electrode terminal 3, which is beneficial to maintaining the structural strength of the electrode terminal 3.

[0129] For example, the device for identifying the first groove 322 can be an image recognition device. For example, the image recognition device includes a charge-coupled device (CCD) camera and a processor connected by a signal. After the CCD camera acquires image information from the side of the electrode terminal 3 with the positioning structure 32, the processor can process the image information to obtain the axis of the first groove 322 in the image, thereby obtaining the axis of the recess 31. With the cover plate 4 covering the recess 31, after the CCD camera acquires image information from the side of the electrode terminal 3 with the positioning structure 32, the processor can process the image information to obtain the axis of the first groove 322 and the axis of the cover plate 4 in the image, thereby obtaining the concentricity of the cover plate 4 and the recess 31.

[0130] In some embodiments, as shown in FIG7, the positioning structure 32 includes a plurality of positioning portions 323 arranged circumferentially spaced along the recess 31.

[0131] The positioning portion 323 may be a part of the positioning structure 32, and multiple positioning portions 323 disposed on the outer periphery of the recess 31 can form the positioning structure 32. By arranging the multiple positioning portions 323 in the positioning structure 32 at intervals along the circumference of the recess 31, the positioning structure 32 formed by the multiple positioning portions 323 is coaxial with the recess 31. For example, the multiple positioning portions 323 may be multiple arc-shaped first grooves 322, or multiple arc-shaped protrusions 321.

[0132] In some embodiments, the positioning structure 32 is an annular structure surrounding the outer periphery of the recess 31.

[0133] The positioning structure 32 is an annular structure surrounding the outer periphery of the recess 31. Specifically, the positioning structure 32 extends circumferentially around the outer periphery of the recess 31, so that the positioning structure 32 is coaxially sleeved on the outside of the recess 31.

[0134] For example, the recess 31 can be configured as a circular structure, and the positioning structure 32 can be configured as a ring concentric with the recess 31, making the processing of the positioning structure 32 and the recess 31 more convenient.

[0135] In some embodiments, the minimum distance C between the positioning structure 32 and the cover plate 4 along the radial direction of the recess 31 is 2mm≤C≤12mm.

[0136] By setting the minimum distance C of the positioning structure 32 from the cover plate 4 along the radial direction of the recess 31 to 2mm≤C≤12mm, not only can enough space be left in the area near the recess 31 to place the formation probe, but also the positioning structure 32 can be prevented from being too close to the edge of the electrode terminal 3, so that the image recognition device can distinguish the positioning structure 32 from the edge of the electrode terminal 3.

[0137] The minimum distance C of the positioning structure 32 radially from the cover plate 4 along the recess 31 can be set to 4mm ≤ C ≤ 10mm. For example, the minimum distance C of the positioning structure 32 radially from the cover plate 4 along the recess 31 can be 6mm, 8mm or 10mm. This not only leaves enough space in the area near the recess 31 for placing the formation probe, but also prevents the positioning structure 32 from getting too close to the edge of the electrode terminal 3, making it easier for the image recognition device to distinguish the positioning structure 32 from the edge of the electrode terminal 3.

[0138] For example, the sidewall of the recess 31 is provided with a stepped surface, and the cover plate 4 abuts against the stepped surface. By connecting the cover plate 4 to the stepped surface, the cover plate 4 does not protrude excessively from the surface of the electrode terminal 3 away from the electrode assembly 2. The bottom wall of the recess 31 is provided with a through hole communicating inward with the receiving cavity, through which electrolyte can be injected into the receiving cavity.

[0139] In some embodiments, the housing 1 includes a housing 11 and an end cap 12. The housing 11 has an opening, and the end cap 12 closes the opening. The housing 11 includes an end wall 111 disposed opposite to the end cap 12. The electrode terminal 3 is disposed on the end wall 111.

[0140] The end cap 12 seals the opening of the housing 11, making the receiving cavity a sealed cavity to accommodate other components of the battery cell 20 and the electrolyte.

[0141] The end wall 111 can be a part on the housing 11 that is opposite to the opening. By setting the electrode terminal 3 on the end wall 111, the housing 11 can provide a more solid support for the electrode terminal 3, so that when the battery cell 20 is connected to the electrical device, the electrode terminal 3 can achieve electrical connection between the battery cell 20 and the electrical device by firmly abutting against the power input terminal of the electrical device.

[0142] For example, the housing 11 can be integrally formed using a stamping process.

[0143] In some embodiments, the electrode assembly 2 includes a second electrode 22 with a polarity opposite to that of the first electrode 21, and the second electrode 22 is electrically connected to the end cap 12.

[0144] The second electrode tab 22 can be a tab with the opposite polarity to the first electrode tab 21. The second electrode tab 22 and the first electrode tab 21 can extend from opposite ends of the electrode assembly 2, respectively. The second electrode tab 22 is connected to the end cap 12, and the first electrode tab 21 is connected to the electrode terminal 3.

[0145] In some embodiments, the cover plate 4 is welded to the electrode terminal 3.

[0146] The cover plate 4 is welded to the electrode terminal 3, or the cover plate 4 is welded to the stepped surface of the side wall of the recess 31. Welding can fuse the material of the cover plate 4 and the material of the electrode terminal 3 together, which not only helps to improve the connection between the cover plate 4 and the electrode terminal 3, but also helps to improve the sealing performance of the cover plate 4 covering the recess 31.

[0147] Some embodiments of this application also provide a battery 100, which includes the battery cell 20 provided by the above-described technical solution.

[0148] Some embodiments of this application also provide an electrical device, which includes the battery 100 provided by the above-described technical solution, the battery 100 being used to provide electrical energy.

[0149] Some embodiments of this application provide a battery cell 20, which includes a housing 1, an electrode assembly 2, electrode terminals 3, and a cover plate 4. The housing 1 has a receiving cavity, the electrode assembly 2 is disposed in the receiving cavity and includes a first tab 21 and a second tab 22 disposed opposite to each other, the electrode terminals 3 have a recess 31, the cover plate 4 is disposed on the side of the electrode terminals 3 away from the electrode assembly 2 and covers the recess 31, and the side of the electrode terminals 3 away from the electrode assembly 2 has a positioning structure 32 that runs along the outer periphery of the recess 31 and is concentric with the recess 31. The positioning structure 32 includes a first groove 322. The housing 1 includes a shell 11 and an end cap 12, the end cap 12 covers the opening of the shell 11, the electrode terminals 3 are electrically connected to the end wall 111 of the shell 11, the first tab 21 is connected to the electrode terminals 3, and the second tab 22 is electrically connected to the end cap 12. In the above structure, since the electrode terminal 3 is provided with a positioning structure 32 along the outer periphery of the recess 31 on the side away from the electrode assembly 2, the position of the cover plate 4 can be determined by the positioning structure 32 during the assembly of the battery cell 20 so as to know the concentricity of the cover plate 4 and the recess 31. This is beneficial to improve the concentricity of the cover plate 4 and the recess 31, improve the connection effect between the cover plate 4 and the electrode terminal 3, and thus improve the sealing effect of the cover plate 4 on the recess 31, which helps to improve the yield rate of the battery cell 20 in the production process.

[0150] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, comprising: a housing having a receiving cavity; an electrode assembly disposed in the receiving cavity and comprising a first tab; an electrode terminal disposed on the housing and electrically connected to the first tab, the electrode terminal being provided with a recess; a cover plate disposed on a side of the electrode terminal distal to the electrode assembly and covering the recess, wherein the side of the electrode terminal distal to the electrode assembly is provided with a positioning structure disposed along a periphery of the recess.

2. The battery cell of claim 1, wherein, The positioning structure is configured to be concentric with the recess.

3. The battery cell of claim 1 or 2, wherein, The positioning structure comprises a protrusion disposed along the periphery of the recess.

4. The battery cell of claim 3, wherein, In an axial direction of the recess, an end of the protrusion distal to the electrode assembly does not exceed the cover plate.

5. The battery cell of any one of claims 1 to 4, wherein, The positioning structure comprises a first groove disposed along the periphery of the recess.

6. The battery cell of claim 5, wherein, The first groove has an opening facing away from the electrode assembly, and in a radial direction of the recess, the opening has a size A, 0.1 mm≤A≤0.8 mm.

7. The battery cell of claim 5 or 6, wherein, The first groove has a depth B in an axial direction of the recess, 0.1 mm≤B≤0.8 mm.

8. The battery cell of any one of claims 1 to 7, wherein, The positioning structure comprises a plurality of positioning portions disposed at intervals in a circumferential direction of the recess.

9. The battery cell of any one of claims 1 to 8, wherein, The positioning structure is an annular structure disposed around the periphery of the recess.

10. The battery cell of any one of claims 1 to 9, wherein, In a radial direction of the recess, the positioning structure has a minimum distance C from the cover plate, 2 mm≤C≤12 mm.

11. The battery cell of any one of claims 1 to 10, wherein, The housing comprises a shell having an opening and an end cover covering the opening, and the shell comprises an end wall disposed opposite the end cover; The electrode terminal is disposed on the end wall.

12. The battery cell of claim 11, wherein, The electrode assembly comprises a second tab opposite in polarity to the first tab, and the second tab is electrically connected to the end cover.

13. The battery cell of any one of claims 1 to 10, wherein, The cover plate is welded to the electrode terminal. 14.A battery comprising the battery cell of any one of claims 1 to 13. 15.An electric device comprising the battery of claim 14, the battery being configured to provide electric energy.

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