Battery monomer, battery device and electric device

Abstract

The invention provides a battery monomer, a battery device and a power utilization device. The battery monomer comprises a shell and an electrode assembly accommodated in the shell, the electrode assembly includes a plurality of first pole pieces and a plurality of second pole pieces. The first pole pieces and the second pole pieces are alternately stacked in the first direction, and the polarities of the first pole pieces and the second pole pieces are opposite. The first pole piece comprises a first pole piece main body and a first pole lug, the first pole lug protrudes out of the edge of the first pole piece main body, and at least one side of the first pole piece main body along the first direction is provided with a concave part. The second pole piece comprises a second pole piece main body and a second tab, at least part of the second pole piece main body is accommodated in the concave part, and the orthographic projection of the second pole piece main body along the first direction is positioned in the orthographic projection of the concave part along the first direction. The reliability of the battery monomer can be improved.

Description

Technical Field

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

[0002] Battery cells are widely used in electronic devices such as mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools. Battery cells can include nickel-cadmium battery cells, nickel-metal hydride battery cells, lithium-ion battery cells, and rechargeable alkaline zinc-manganese battery cells, among others.

[0003] In the development of battery technology, improving the reliability of individual battery cells has always been a research direction. Summary of the Invention

[0004] In view of the above problems, this application provides a battery cell, a battery device, and an electrical device that can improve the reliability of the battery cell.

[0005] In a first aspect, this application provides a battery cell, which includes a housing and an electrode assembly housed within the housing. The electrode assembly includes a plurality of first electrodes and a plurality of second electrodes. The first electrodes and second electrodes are alternately stacked along a first direction, and the first electrodes and second electrodes have opposite polarities. The first electrode includes a first electrode body and a first tab, the first tab protruding from the edge of the first electrode body, and the first electrode body has a recess on at least one side along the first direction. The second electrode includes a second electrode body and a second tab, at least a portion of the second electrode body is housed within the recess, and the orthographic projection of the second electrode body along the first direction lies within the orthographic projection of the recess along the first direction.

[0006] In the above scheme, by setting a recess and accommodating the main body of the second electrode within the recess, the distance between the areas of two adjacent first electrodes that extend beyond the second electrode is shortened, thereby reducing the risk of electrode breakage due to excessive bending radius of the areas of adjacent first electrodes that extend beyond the second electrode during the manufacturing process, and improving the reliability of the battery cell.

[0007] In some embodiments, the first electrode body includes a first current collector, a first active material layer, and a support structure. A first tab is connected to the first current collector, the first active material layer is disposed on the surface of the first current collector, and the support structure is connected to the first active material layer and disposed circumferentially along the first electrode body. At least a portion of the support structure protrudes from the surface of the first active material layer away from the surface of the first current collector. The support structure and the first active material layer enclose a recess.

[0008] In the above scheme, by setting a support structure to shorten the distance between the overhang regions of two adjacent first electrodes, the risk of the overhang region of the first electrode breaking during the manufacturing process is reduced, thereby improving the reliability of the battery cell.

[0009] In some embodiments, the support structure includes a first portion and a second portion, the second portion protruding from the first portion along a first direction, the second portion forming at least a portion of the sidewall of the recess, and the orthographic projection of the edge of the second electrode body along the first direction lies within the orthographic projection of the first portion along the first direction.

[0010] In the above scheme, the above arrangement helps to increase the overall area of ​​the second electrode, reducing the risk of ion precipitation in the battery cells. It also reduces the risk of short circuits in the battery cells caused by burrs at the edge of the second electrode and overlap with the first electrode.

[0011] In some embodiments, the first active material layer includes a first active material body and a thinning portion, the thinning portion being disposed circumferentially along the first active material body, and at least a portion of the first portion being located on the side of the thinning portion opposite to the first current collector.

[0012] In the above scheme, the above settings help to increase the connection area between the support structure and the first electrode body, thereby reducing the possibility of separation between the support structure and the first electrode body. It also helps to disperse the interaction force when the support structures abut each other to the first electrode body, thereby reducing the risk of the support structure breaking the first electrode body due to the abutting of the support structures.

[0013] In some embodiments, the surface of the first portion facing away from the first current collector is flush with the surface of the first active material body facing away from the first current collector, so as to reduce the possibility that the edge thickness of the first electrode and the second electrode after being stacked is greater than the thickness of the central region of the first electrode and the second electrode, thereby improving the thickness uniformity of the electrode assembly and improving the reliability of the battery cell.

[0014] In some embodiments, the number of support structures includes two, which are respectively disposed on opposite sides of the first current collector along a first direction.

[0015] In the above scheme, by setting support structures on both sides of the first current collector, when the overhang regions in the two first electrodes are relatively close, the support structures on the two first electrodes will disperse the interaction force to the two electrodes, further reducing the possibility of overhang region breakage during the manufacturing process and improving the reliability of the battery cell.

[0016] In some embodiments, the dimension of the second portion along the first direction is equal to half the dimension of the second electrode along the first direction, so that after the support structures on the two first electrodes are interlocked, the second electrode is accommodated in the recess of the two first electrodes, thereby reducing the possibility of misalignment of the first and second electrodes.

[0017] In some embodiments, the support structure is located on one side of the first current collector along a first direction.

[0018] In the above scheme, by setting support structures on both sides of the first current collector, it is beneficial to reduce the manufacturing process steps of the first electrode, improve the production efficiency of the first electrode, and reduce the manufacturing cost of the battery cell.

[0019] In some embodiments, the dimension of the second portion along the first direction is equal to the dimension of the second electrode along the first direction. This helps to reduce the redundant setting of the support structure while enabling the support structure on the first electrode to support the overhang area of ​​the adjacent first electrode body, reducing the possibility of the first electrode bending during the manufacturing process and improving the reliability of the battery cell.

[0020] In some embodiments, the second electrode tab protrudes from the edge of the second electrode body, the second portion is provided with an opening, and the second electrode tab protrudes from the opening into the recess.

[0021] In the above scheme, the second electrode tab is provided by protruding from the periphery of the second electrode body, the second electrode body is accommodated in the recess, and the opening provided in the second part forms a notch on the side wall of the recess, so that the second electrode tab can extend into the recess through the opening, thereby reducing the possibility of interference between the side wall of the recess and the second electrode tab.

[0022] In some embodiments, the first electrode is a positive electrode and the second electrode is a negative electrode. Combining the above technical solution, the orthographic projection of the edge of the second electrode body in the first direction is set within the orthographic projection of the first part in the first direction, which helps to reduce the risk of ion precipitation in the battery cell and reduce the risk of short circuit in the battery cell caused by the burrs on the edge of the second electrode body overlapping with the first electrode.

[0023] In some embodiments, the surface of the second electrode is provided with a solid electrolyte layer, which covers the body of the second electrode and at least a portion of the second electrode tab.

[0024] In the above scheme, by covering the second electrode body and at least part of the second electrode tab with the solid electrolyte layer, it is beneficial to improve the separation effect of the solid electrolyte layer on the oppositely arranged first active material layer and second active material layer, reduce the possibility of short circuit between the oppositely arranged first active material layer and second active material layer, thereby reducing the risk of short circuit in the battery cell and improving the reliability of the battery cell.

[0025] Secondly, embodiments of this application provide an electrical device, including the battery device in any of the foregoing embodiments, the battery device being used to provide electrical energy.

[0026] Thirdly, embodiments of this application provide an electrical device, including the battery device in any of the foregoing embodiments, the battery device being used to provide electrical energy.

[0027] 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

[0028] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application;

[0030] Figure 2 This is a schematic diagram of the exploded structure of a battery provided in an embodiment of this application;

[0031] Figure 3 This is a schematic diagram of the structure of a battery module provided in an embodiment of this application;

[0032] Figure 4 This is a schematic diagram of the structure of a single battery cell provided in an embodiment of this application;

[0033] Figure 5 This is a schematic cross-sectional view of a battery cell provided in an embodiment of this application;

[0034] Figure 6 This is an exploded cross-sectional view of an electrode assembly in a battery cell provided in an embodiment of this application;

[0035] Figure 7 yes Figure 6 A schematic diagram of an enlarged structure of P;

[0036] Figure 8 This is a schematic diagram of the structure of the first electrode in a battery cell provided in an embodiment of this application;

[0037] Figure 9 yes Figure 6 A schematic diagram of another enlarged structure of P;

[0038] Figure 10 This is an exploded schematic diagram of an electrode assembly in a battery cell provided in an embodiment of this application;

[0039] Figure 11 yes Figure 10 A schematic diagram of the enlarged structure of Q;

[0040] Figure 12 This is a schematic diagram of the structure of the second electrode in a battery cell provided in an embodiment of this application.

[0041] Marker description

[0042] 1000, vehicles;

[0043] 100, Battery assembly; 200, Controller; 300, Motor; 400, Housing; 410, First housing section; 420, Second housing section; 430, Receiving section; 500, Battery module;

[0044] 110. Battery cell; 101. Casing; 102. Electrode assembly;

[0045] 10. First electrode sheet; 11. First electrode sheet body; 111. First current collector; 112. First active material layer; 112a. First active material body; 112b. Thinning portion; 113. Support structure; 113a. First section; 113b. Second section; 12. First electrode tab; 13. Recess;

[0046] 20. Second electrode; 21. Second electrode body; 211. Second current collector; 212. Second active material layer; 22. Second electrode tab; 23. Solid electrolyte layer;

[0047] K1, opening; Z, first direction. Detailed Implementation

[0048] 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.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0050] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0051] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0052] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0053] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0054] 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," and "circumferential" 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 are not intended to 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.

[0055] In the description of the embodiments of this application, unless otherwise expressly specified and limited, 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.

[0056] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0057] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0058] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator, with the separator positioned between the positive and negative electrodes. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0059] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0060] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0061] As an example, the positive current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0062] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.8 Co 0.15 Al 0.05 At least one of O2 and its modified compounds. Modified compounds refer to substances obtained by modification methods such as doping or coating based on the above-mentioned substances.

[0063] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, a positive electrode active material is filled and / or deposited within the foamed metal.

[0064] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0065] As an example, the negative electrode current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. The composite current collector may include a polymer material substrate and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0066] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0067] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0068] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials for battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0069] In some embodiments, the negative electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When foamed metal is used as the negative electrode sheet, the surface of the foamed metal may or may not have a negative electrode active material.

[0070] As an example, negative electrode active materials can be filled or / and deposited within the negative electrode current collector.

[0071] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0072] In some embodiments, the electrode assembly further includes an isolator disposed between the positive and negative electrodes.

[0073] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0074] 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 solid-state.

[0075] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0076] As an example, the polymers of polymeric solid electrolytes may include polyethers (polyoxyethylene), polysiloxanes, polycarbonates, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids, cellulose, etc.

[0077] As an example, inorganic solid electrolytes can be one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium-germanium-phosphorus-sulfur, sulfosilium-germanium), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0078] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0079] In some implementations, the electrode assembly is a stacked structure.

[0080] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0081] 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.

[0082] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0083] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0084] 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.

[0085] In some embodiments, the battery cell may include a casing. The casing may be a steel casing, an aluminum casing, a plastic casing (such as a polypropylene casing), a composite metal casing (such as a copper-aluminum composite casing), or an aluminum-plastic film, etc. In some embodiments, the casing may be a sealed structure or a non-sealed structure. As an example, when the casing is a non-sealed structure, the casing serves to protect the electrode assembly, and a sealing bag is included between the casing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag may be a bag-shaped insulating component or an aluminum-plastic film. When the casing is a sealed structure, it is used to encapsulate components such as the electrode assembly and electrolyte.

[0086] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries. This application does not have any particular limitations.

[0087] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells connected in series, parallel, or mixed connections via a busbar.

[0088] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells.

[0089] As an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form an independent module. As another example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0090] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cells housed within the housing.

[0091] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0092] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0093] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first enclosure may be a top cover or a bottom plate.

[0094] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

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

[0096] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use individual battery cells, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft.

[0097] The development of battery technology must take into account multiple design factors, such as energy density, cycle life, discharge capacity, charge-discharge rate and other performance parameters. In addition, the reliability of individual battery cells also needs to be considered.

[0098] A battery cell includes electrode components, which are the core components of the battery cell where electrochemical reactions occur. During manufacturing, the negative and positive electrode sheets are typically aligned and stacked. However, due to limitations in manufacturing processes, there is often some misalignment between the negative and positive electrode sheets perpendicular to the stacking direction. This prevents them from aligning properly, resulting in a portion of the positive electrode not corresponding to the negative electrode. Consequently, active ions extracted from the positive electrode cannot effectively embed into the negative electrode, leading to ion deposition problems between the negative and positive electrode sheets.

[0099] Therefore, when designing electrode components, the negative electrode is usually designed to be excessive, exceeding the positive electrode. This excess portion is called the overhang region. There is no positive electrode supporting the overhang regions of adjacent negative electrodes. In some manufacturing processes (such as isostatic pressing densification), this can easily lead to bending or even breakage of the overhang region of the negative electrode, resulting in a decrease in the reliability of the battery cell.

[0100] Based on the above-mentioned technical problems, this application provides a technical solution that, by setting a recess and accommodating the main body of the second electrode within the recess, shortens the distance between the areas of two adjacent first electrodes that extend beyond the second electrode, thereby reducing the risk of electrode breakage due to excessive bending radius of the areas of adjacent first electrodes extending beyond the second electrode during the manufacturing process, and improving the reliability of the battery cell.

[0101] The battery cells described in this application are not limited to the electrical devices described above, but for the sake of brevity, the following embodiments are all illustrated using electric vehicles as an example.

[0102] Please see Figure 1 , Figure 1 This is a schematic diagram of a vehicle structure provided in an embodiment 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 device 100 can be installed inside the vehicle 1000; specifically, for example, the battery device 100 can be installed at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 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, for example, is used to control the battery to supply power to the motor 300. The battery can be used for starting the vehicle 1000, navigation, etc. Of course, the battery device 100 can also be used to drive the vehicle 1000, replacing or partially replacing gasoline or natural gas to provide propulsion for the vehicle 1000.

[0103] Figure 2 This is a schematic diagram of the exploded structure of a battery provided in an embodiment of this application. For example... Figure 2 As shown, the battery device 100 includes a housing 400 and battery cells (not shown in the figure), with the battery cells housed within the housing 400.

[0104] The housing 400 is used to house individual battery cells, and the housing 400 can have various structures. In some embodiments, the housing 400 may include a first housing portion 410 and a second housing portion 420, which overlap each other, and together define a receiving portion 430 for housing the individual battery cells. The second housing portion 420 may be a hollow structure with one end open, and the first housing portion 410 may be a plate-like structure, with the first housing portion 410 covering the open side of the second housing portion 420 to form a housing with the receiving portion 430; alternatively, both the first housing portion 410 and the second housing portion 420 may be hollow structures with one side open, with the open side of the first housing portion 410 covering the open side of the second housing portion 420 to form a housing 400 with the receiving portion 430. Of course, the first housing portion 410 and the second housing portion 420 can have various shapes, such as cylinders, cuboids, etc.

[0105] In the battery device 100, there can be multiple battery cells. These multiple battery cells can be connected in series, parallel, or in a hybrid configuration. A hybrid configuration means that multiple battery cells are connected in both series and parallel connections. Multiple battery cells can be directly connected in series, parallel, or in a hybrid configuration, and then the entire assembly of these multiple battery cells is housed within the housing 400. Alternatively, multiple battery cells can first be connected in series, parallel, or in a hybrid configuration to form a battery module 500, and then these battery modules 500 can be connected in series, parallel, or in a hybrid configuration to form a whole, which is then housed within the housing 400.

[0106] Figure 3 This is a schematic diagram of the structure of a battery module provided in an embodiment of this application.

[0107] In some embodiments, such as Figure 3 As shown, there are multiple battery cells 110. These multiple battery cells 110 are first connected in series, parallel, or in a mixed manner to form a battery module 500. The multiple battery modules 500 are then connected in series, parallel, or in a mixed manner to form a whole, which is housed in the casing.

[0108] Figure 4 This is a schematic diagram of the structure of a battery cell provided in an embodiment of this application. Figure 5 This is a cross-sectional structural diagram of a battery cell provided in an embodiment of this application. Figure 6 This is an exploded cross-sectional view of an electrode assembly in a battery cell provided in an embodiment of this application. Figure 7 yes Figure 6 A schematic diagram of an enlarged structure of P.

[0109] Please see Figures 4 to 7This application provides a battery cell 110, which includes a housing 101 and an electrode assembly 102 housed within the housing 101. The electrode assembly 102 includes a plurality of first electrode plates 10 and a plurality of second electrode plates 20. The first electrode plates 10 and second electrode plates 20 are alternately stacked along a first direction Z, and the first electrode plates 10 and second electrode plates 20 have opposite polarities. The first electrode plate 10 includes a first electrode plate body 11 and a first electrode tab 12, the first electrode tab 12 protruding from the edge of the first electrode plate body 11, and the first electrode plate body 11 has a recess 13 on at least one side along the first direction Z. The second electrode plate 20 includes a second electrode plate body 21 and a second electrode tab 22, at least a portion of the second electrode plate body 21 is housed within the recess 13, and the orthographic projection of the second electrode plate body 21 along the first direction Z lies within the orthographic projection of the recess 13 along the first direction Z.

[0110] Optionally, one of the first electrode 10 and the second electrode 20 is a positive electrode, and the other is a negative electrode. For example, the first electrode 10 is a positive electrode, and the second electrode 20 is a negative electrode. Alternatively, the first electrode 10 is a negative electrode, and the second electrode 20 is a positive electrode.

[0111] Optionally, the electrode assembly can be a stacked structure, for example, multiple first electrodes and multiple second electrodes can be stacked alternately to form an electrode assembly.

[0112] Optionally, the first tab 12 and the second tab 22 can be located on the same side of the electrode assembly 102, or they can be located on different sides.

[0113] It is understood that the first electrode body 11 has a recess 13 on at least one side along the first direction Z, and a portion of the structure of the first electrode body 11 protrudes, the protruding portion enclosing and forming the sidewall of the recess 13. Optionally, the protruding portion can be the overhang region of the first electrode body 11.

[0114] In some examples, the first electrode body 11 has a recess 13 on one side along the first direction Z. In other examples, the first electrode body 11 has recesses 13 on both sides along the first direction Z.

[0115] For example, the orthographic projections of the recesses 13 on both sides of the first electrode body 11 along the first direction Z can be completely coincident. Of course, the orthographic projections of the recesses 13 on opposite sides of the first electrode body 11 along the first direction Z can also be overlapping.

[0116] Optionally, the depths of the recesses 13 on both sides of the first electrode body 11 along the first direction Z can be the same, or they can be different.

[0117] Optionally, the entire structure of the second electrode body 21 along the first direction Z is accommodated within the recess 13; or, a portion of the structure of the second electrode body 21 along the first direction Z is accommodated within the recess 13. Furthermore, in the second direction, the entire structure of the second electrode body 21 is located within the recess 13. The second direction is perpendicular to the first direction Z.

[0118] Optionally, the second electrode body 21 and the sidewalls of the recess 13 can be fitted together. Alternatively, there can be a gap between the second electrode body 21 and the sidewalls of the recess 13. It is understood that when the second electrode body 21 and the sidewalls of the recess 13 are fitted together, an insulating material is provided between the second electrode body 21 and the sidewalls of the recess 13.

[0119] In the technical solution of this application embodiment, by setting a recess 13 and accommodating the second electrode body 21 in the recess 13, the distance between the regions of two adjacent first electrodes 10 that extend beyond the second electrode 20 is shortened, thereby reducing the risk of electrode breakage caused by excessive bending radius of the regions of adjacent first electrodes 10 that extend beyond the second electrode 20 during the manufacturing process, and improving the reliability of the battery cell 110.

[0120] Figure 8 This is a schematic diagram of the structure of the first electrode in a battery cell provided in an embodiment of this application.

[0121] In some alternative embodiments, please refer to Figure 7 and Figure 8 The first electrode body 11 includes a first current collector 111, a first active material layer 112, and a support structure 113. A first tab 12 is connected to the first current collector 111. The first active material layer 112 is disposed on the surface of the first current collector 111. The support structure 113 is connected to the first active material layer 112 and is disposed along the circumference of the first electrode body 11. At least a portion of the support structure 113 protrudes beyond the first active material layer 112 and faces away from the surface of the first current collector 111. The support structure 113 and the first active material layer 112 enclose a recess 13.

[0122] In some examples, the first electrode body 11 includes a first current collector 111, a first active material layer 112, and a support structure 113. The first current collector 111 has two surfaces opposite each other in its own thickness direction, and the first active material layer 112 is disposed on either or both of the two opposite surfaces of the first current collector 111. Optionally, the support structure 113 is disposed on either or both of the two opposite surfaces of the first current collector 111.

[0123] The first tab 12 is connected to the periphery of the first current collector 111. The second electrode body 21 may include the second current collector 211 and the second active material layer 212. The second tab 22 is connected to the periphery of the second current collector 211. Optionally, the first tab 12 and the second tab 22 may be located on the same side of the electrode assembly 102; or, the first tab 12 and the second tab 22 may be located on different sides of the electrode assembly 102.

[0124] In some examples, the support structure 113 may be located on the side of the first active material layer 112 facing away from the first current collector 111. In other examples, the first current collector 111 has an uncoated area and a coated area, with the support structure 113 disposed in the uncoated area and the first active material layer 112 disposed in the coated area. Optionally, the sidewalls of the support structure 113 and the sidewalls of the first active material layer 112 may be fitted together; or, there may be a gap between the sidewalls of the support structure 113 and the sidewalls of the first active material layer 112.

[0125] The support structure 113 is arranged circumferentially along the first electrode body 11. It is understood that the first electrode body 11 has an edge, and the support structure 113 is located at the edge of the first electrode body 11 and extends along the edge of the first electrode body 11. For example, the first electrode body 11 is rectangular in shape, and the support structure 113 forms a rectangular frame around the edge of the rectangle. Optionally, the support structure 113 can be a continuous structure, or it can be multiple spaced substructures located at different edges of the rectangle.

[0126] In some embodiments, the support structure 113 protrudes entirely from the surface of the first active material layer 112 facing away from the first current collector 111. In other embodiments, a portion of the support structure 113 protrudes from the surface of the first active material layer 112 facing away from the first current collector 111, and another portion of the support structure 113 may be flush with the surface of the first active material layer 112 facing away from the first current collector 111, or the surface of the first active material layer 112 facing away from the first current collector 111 may protrude from another portion of the support structure 113. Of course, the other portion of the support structure 113 may include two sub-parts, one of which is flush with the surface of the first active material layer 112 facing away from the first current collector 111, and the other sub-part protrudes from the surface of the first active material layer 112 facing away from the first current collector 111.

[0127] The support structure 113 and the first active material layer 112 enclose and form a recess 13. This can be understood as the support structure 113 forming the sidewall of the recess 13, and the first active material layer 112 forming the bottom wall of the recess 13. Of course, a portion of the support structure 113 can also form the bottom wall of the recess 13.

[0128] Optionally, the support structure 113 can be made of insulating material.

[0129] Optionally, the support structure 113 can be located at the root of the first tab 12. The support structure 113 can support the first tab 12, thereby reducing the risk of the first tab 12 bending at too large an angle or even breaking during the manufacturing process. In addition, the support structure 113 can also support the second tab 22, thereby reducing the risk of the second tab 22 bending at too large an angle or even breaking during the manufacturing process.

[0130] In these alternative embodiments, by providing a support structure 113 to shorten the spacing between the overhang regions of two adjacent first electrode sheets 10, the risk of the overhang regions of the first electrode sheets 10 breaking during the manufacturing process is reduced, thereby improving the reliability of the battery cell 110.

[0131] In some alternative embodiments, please refer to Figure 7 and Figure 8 The support structure 113 includes a first portion 113a and a second portion 113b. The second portion 113b protrudes from the first portion 113a along the first direction Z. The second portion 113b forms at least a portion of the sidewall of the recess 13. The orthographic projection of the edge of the second electrode body 21 along the first direction Z is located within the orthographic projection of the first portion 113a along the first direction Z.

[0132] Optionally, the first portion 113a and the second portion 113b can be a stacked structure. Alternatively, the first portion 113a and the second portion 113b can also be a single integral structure.

[0133] In some embodiments, the second portion 113b protrudes from the first portion 113a, the second portion 113b forms the sidewall of the recess 13, and the first portion 113a and the first active material layer 112 form the bottom wall of the recess 13.

[0134] In some embodiments, the second portion 113b may form a sidewall of the recess 13. In other embodiments, the second portion 113b forms part of the sidewall of the recess 13, and the first portion 113a may form another part of the sidewall of the recess 13. Alternatively, the support structure 113 may further include a third portion located on the side of the second portion 113b opposite to the first portion 113a, the second portion 113b and the third portion together forming a sidewall of the recess 13, a stepped surface being provided between the third portion and the second portion 113b, and a portion of the second electrode body 21 overlapping the stepped surface. For example, the second active material layer 212 on one side of the second electrode body 21 along its own thickness direction is located in the recess 13 and is disposed close to the first active material layer 112. A part of the second current collector 211 and the second active material layer 212 on the side of the second current collector 211 facing away from the first active material layer 112 overlap on the step surface to increase the area of ​​the active material layer on one side of the second electrode 20. When the first electrode 10 is a positive electrode and the second electrode 20 is a negative electrode, the area of ​​the active material layer of the second electrode 20 can be made larger than the area of ​​the active material layer of the first electrode 10, thereby reducing the risk of ion precipitation in the battery cell 110.

[0135] It is understandable that when the first electrode 10 is a positive electrode and the second electrode 20 is a negative electrode, the orthogonal projection of the edge of the second electrode body 21 along the first direction Z is located within the orthogonal projection of the first portion 113a along the first direction Z, which can increase the area of ​​the active material layer of the second electrode 20 and reduce the risk of ion precipitation in the battery cell 110.

[0136] In these alternative embodiments, the above-described configuration helps to increase the overall area of ​​the second electrode 20, reducing the risk of ion deposition in the battery cell 110. It also reduces the risk of short circuits in the battery cell 110 caused by burrs at the edge of the second electrode 20 and overlap with the first electrode 10.

[0137] In some alternative embodiments, please refer to Figure 7 The first active material layer 112 includes a first active material body 112a and a thinning portion 112b. The thinning portion is arranged circumferentially along the first active material body 112a, and at least a portion of the first portion 113a is located on the side of the thinning portion 112b facing away from the first current collector 111.

[0138] Optionally, the thickness of the first active substance body 112a is greater than the thickness of the thinned portion 112b.

[0139] Optionally, the thickness of the thinned portion 112b may gradually increase along the direction close to the first active material body 112a.

[0140] Optionally, the orthographic projection of the first portion 113a along the first direction Z and the orthographic projection of the thinned portion 112b along the first direction Z can be arranged to overlap. For example, the orthographic projection of the first portion 113a along the first direction Z and the orthographic projection of the thinned portion 112b along the first direction Z can be arranged to overlap.

[0141] Optionally, a portion of the first section 113a may be located on the side of the thinning section 112b facing away from the first current collector 111, and another portion of the first section 113a may be disposed in contact with the sidewall of the thinning section 112b.

[0142] In these alternative embodiments, the above-described arrangement helps to increase the connection area between the support structure 113 and the first electrode body 11, thereby reducing the possibility of separation between the support structure 113 and the first electrode body 11. It also helps to disperse the interaction force when the support structures 113 abut against each other to the first electrode body 11, thereby reducing the risk that the support structure 113 will break the first electrode body 11 due to the abutting of the support structures 113.

[0143] In some alternative embodiments, please refer to Figure 7 The surface of the first portion 113a facing away from the first current collector 111 is flush with the surface of the first active material body facing away from the first current collector 111, so as to reduce the possibility that the edge thickness of the first electrode 10 and the second electrode 20 after being stacked is greater than the thickness of the central region of the first electrode 10 and the second electrode 20, thereby improving the thickness uniformity of the electrode assembly 102 and improving the reliability of the battery cell 110.

[0144] In some alternative embodiments, please refer to Figure 7 The number of support structures 113 includes two, and the two support structures 113 are respectively located on opposite sides of the first current collector 111 along the first direction Z.

[0145] Optionally, the orthographic projections of the two support structures 113 in the first direction Z can be overlapping. Of course, the orthographic projections of the two support structures 113 in the first direction Z can also be overlapping or spaced apart.

[0146] It is understood that multiple first electrode sheets 10 and multiple second electrode sheets 20 are overlapped, with one second electrode sheet 20 positioned between two first electrode sheets 10. The opposing support structures 113 of the two first electrode sheets 10 interlock to form a receiving space, within which the second electrode sheet 20 can be accommodated. Optionally, the two opposing support structures 113 of the two first electrode sheets 10 can be configured to abut or be spaced apart. Optionally, the two opposing support structures 113 of the two first electrode sheets 10 can be configured to fit together; for example, one support structure 113 may have a limiting groove, and the other support structure 113 may have a limiting post. During the manufacturing process, the limiting post can extend into the limiting groove and move within the limiting groove along the first direction Z. Optionally, the limiting post can also serve a guiding function to reduce the alignment accuracy of the two opposing support structures 113.

[0147] In this embodiment, by providing support structures 113 on both sides of the first current collector 111, the support structures 113 on the two first electrodes 10 will disperse the interaction force to the two electrodes when the overhang regions in the two first electrodes 10 are relatively close, thereby further reducing the possibility of overhang region breakage during the manufacturing process and improving the reliability of the battery cell 110.

[0148] In some alternative embodiments, please refer to Figure 5 and Figure 7 The dimension of the second portion 113b along the first direction Z is equal to half the dimension of the second electrode 20 along the first direction Z, so that after the support structures 113 on the two first electrodes 10 are interlocked, the second electrode 20 is accommodated in the recess 13 of the two first electrodes 10, thereby reducing the possibility of misalignment of the first electrode 10 and the second electrode 20.

[0149] For example, the second portion 113b has a dimension d along the first direction Z, and the second electrode 20 has a dimension D along the first direction Z. The relationship between d and D is d = 0.5D.

[0150] Figure 9 yes Figure 6 Another enlarged structural diagram of P.

[0151] In some alternative embodiments, please refer to Figure 9 The support structure 113 is located on one side of the first current collector 111 along the first direction Z.

[0152] It is understood that multiple first electrodes 10 and multiple second electrodes 20 are arranged in an overlapping manner, with one second electrode 20 positioned between two first electrodes 10. The support structure 113 of one of the first electrodes 10 houses the second electrode 20, and the side of the other first electrode 10 without the support structure 113 faces the support structure 113 of one of the first electrodes 10. Here, "the side without the support structure 113" refers to the side of the other first electrode 10 opposite to the side with the support structure 113. Optionally, the surface of the other first electrode 10 without the support structure 113 may abut against the support structure 113 of one of the first electrodes 10; alternatively, they may be spaced apart. It should be noted that when the support structure 113 is only located on one side of the first current collector 111 along the first direction Z, the side without the support structure 113 needs to have an insulating film layer in the area that abuts against the support structure 113, in order to reduce the risk that the area of ​​the active material layer on the side without the support structure 113 exceeds the area of ​​the active material layer of the second electrode 20, thereby leading to ion precipitation.

[0153] In this embodiment of the application, by providing support structures 113 on both sides of the first current collector 111, it is beneficial to reduce the manufacturing process steps of the first electrode 10, improve the production efficiency of the first electrode 10, and reduce the manufacturing cost of the battery cell 110.

[0154] In some alternative embodiments, please refer to Figure 9 The dimension of the second part 113b along the first direction Z is equal to the dimension of the second electrode 20 along the first direction Z. This helps to reduce the redundant setting of the support structure 113, while enabling the support structure 113 on the first electrode 10 to support the overhang area of ​​the adjacent first electrode body 11, reducing the possibility of the first electrode 10 bending during the manufacturing process and improving the reliability of the battery cell 110.

[0155] For example, the second part 113b has a dimension d along the first direction Z, and the second electrode 20 has a dimension D along the first direction Z. d and D satisfy the relationship d = D.

[0156] Figure 10 This is an exploded schematic diagram of an electrode assembly in a battery cell provided in an embodiment of this application. Figure 11 yes Figure 10 A magnified schematic diagram of the Q-axis.

[0157] In some alternative embodiments, please refer to Figure 10 and Figure 11 The second electrode tab 22 protrudes from the edge of the second electrode body 21, and the second portion 113b is provided with an opening K1, through which the second electrode tab 22 protrudes from the recess 13.

[0158] It is understood that the second electrode 20 includes a second electrode body 21 and a second electrode tab 22. The second electrode tab protrudes from the periphery of the second electrode body 21. The second electrode body 21 is accommodated in the recess 13. The opening K1 provided in the second portion 113b forms a notch on the side wall of the recess 13. The second electrode tab 22 can extend out of the recess 13 through the opening K1 to reduce the possibility of interference between the side wall of the recess and the second electrode tab 22.

[0159] Optionally, the orthographic shape of the second portion 113b in the first direction Z can be a continuous structure.

[0160] In some alternative embodiments, the first electrode 10 is a positive electrode and the second electrode 20 is a negative electrode. In combination with the above technical solution, the edge of the second electrode body 21 is placed in the orthogonal projection of the first part 113a in the first direction Z. This helps to reduce the risk of ion precipitation in the battery cell 110 and reduce the risk of short circuit in the battery cell 110 caused by the burrs on the edge of the second electrode body 21 overlapping with the first electrode 10.

[0161] Figure 12 This is a schematic diagram of the structure of the second electrode in a battery cell provided in an embodiment of this application.

[0162] In some alternative embodiments, please refer to Figure 12 The surface of the second electrode 20 is provided with a solid electrolyte layer 23, which covers the second electrode body 21 and at least part of the second electrode tab 22.

[0163] Optionally, the solid electrolyte layer 23 is configured to cover the second active material layer 212.

[0164] Optionally, the solid electrolyte layer 23 may also cover the root of the second tab 22. Optionally, the solid electrolyte layer 23 may extend from the root of the second tab 22 to the top of the second tab to a predetermined position. Here, "root" refers to the area where the second tab 22 connects to the second electrode body 21, and "top" refers to the side of the second tab 22 facing away from the second electrode body 21.

[0165] In these alternative embodiments, by covering the second electrode body 21 and at least part of the second tab 22 with the solid electrolyte layer 23, it is beneficial to improve the separation effect of the solid electrolyte layer 23 on the oppositely arranged first active material layer 112 and second active material layer 212, reduce the possibility of short circuit between the oppositely arranged first active material layer 112 and second active material layer 212, thereby reducing the risk of short circuit in the battery cell 110 and improving the reliability of the battery cell.

[0166] Secondly, embodiments of this application provide a battery device 100, including the battery cell 110 in any of the foregoing embodiments.

[0167] Thirdly, embodiments of this application provide an electrical device, including the battery device 100 in any of the foregoing embodiments, the battery device being used to provide electrical energy.

[0168] According to some embodiments of this application, please refer to Figures 5 to 8 as well as Figures 10 to 12 The battery cell 110 includes a housing 101 and an electrode assembly 102 housed within the housing. The electrode assembly includes a plurality of first electrode plates 10 and a plurality of second electrode plates 20, with the first and second electrode plates alternately stacked along a first direction Z. The first electrode plates 10 and the second electrode plates 20 have opposite polarities. The first electrode plate 10 includes a first electrode plate body 11 and a first electrode tab 12. The first electrode tab protrudes from the edge of the first electrode plate body 11, and the first electrode plate body has a recess 13 on at least one side along the first direction Z. The second electrode plate 20 includes a second electrode plate body 21 and a second electrode tab 22. At least a portion of the second electrode plate body is housed within the recess 13, and the orthographic projection of the second electrode plate body 21 along the first direction Z lies within the orthographic projection of the recess 13 along the first direction Z. The first electrode plate 10 is a positive electrode plate.

[0169] The first electrode body 11 includes a first current collector 111, a first active material layer 112, and a support structure 113. A first tab 12 is connected to the first current collector 111. The first active material layer 112 is disposed on the surface of the first current collector 111. The support structure 113 is connected to the first active material layer 112 and is disposed along the circumference of the first electrode body 11. The support structure 113 includes a first portion 113a and a second portion 113b. The second portion protrudes from the first portion 113a along a first direction Z. The second portion 113b forms at least a portion of the sidewall of the recess 13. The orthographic projection of the edge of the second electrode body 21 along the first direction Z lies within the orthographic projection of the first portion 113a along the first direction Z.

[0170] The first active material layer 112 includes a first active material body 112a and a thinning portion 112b. The thinning portion is disposed circumferentially along the first active material body 112a. At least a portion of the first segment 113a is located on the side of the thinning portion 112b facing away from the first current collector 111. The surface of the first segment 113a facing away from the first current collector 111 is flush with the surface of the first active material body facing away from the first current collector 111.

[0171] The number of support structures 113 includes two, which are respectively located on opposite sides of the first current collector 111 along the first direction Z. The dimension of the second portion 113b along the first direction Z is equal to half the dimension of the second electrode 20 along the first direction Z.

[0172] The second electrode tab 22 protrudes from the edge of the second electrode body 21, and the second portion 113b is provided with an opening K1, through which the second electrode tab 22 protrudes from the recess 13.

[0173] The surface of the second electrode 20 is provided with a solid electrolyte layer 23, which covers the second electrode body 21 and at least part of the second electrode tab 22.

[0174] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that, The device includes a housing and an electrode assembly housed within the housing. The electrode assembly includes a plurality of first electrodes and a plurality of second electrodes, wherein the first electrodes and second electrodes are alternately stacked along a first direction and the first electrodes and second electrodes have opposite polarities. The first electrode includes a first electrode body and a first electrode tab, the first electrode tab protruding from the edge of the first electrode body, and the first electrode body having a recess on at least one side along the first direction; The second electrode includes a second electrode body and a second electrode tab, at least a portion of the second electrode body is accommodated within the recess, and the orthographic projection of the second electrode body along the first direction lies within the orthographic projection of the recess along the first direction.

2. The battery cell according to claim 1, characterized in that, The first electrode body includes a first current collector, a first active material layer, and a support structure. The first electrode tab is connected to the first current collector. The first active material layer is disposed on the surface of the first current collector. The support structure is connected to the first active material layer and disposed along the circumference of the first electrode body. At least a portion of the support structure protrudes from the surface of the first active material layer away from the surface of the first current collector. The support structure and the first active material layer enclose the recess.

3. The battery cell according to claim 2, characterized in that, The support structure includes a first portion and a second portion, the second portion protruding from the first portion along the first direction, the second portion forming at least a portion of the sidewall of the recess, and the orthographic projection of the edge of the second electrode body along the first direction lies within the orthographic projection of the first portion along the first direction.

4. The battery cell according to claim 3, characterized in that, The first active material layer includes a first active material body and a thinning portion. The thinning portion is disposed circumferentially along the first active material body, and at least a portion of the first portion is located on the side of the thinning portion opposite to the first current collector.

5. The battery cell according to claim 4, characterized in that, The surface of the first portion facing away from the first current collector is flush with the surface of the first active material body facing away from the first current collector.

6. The battery cell according to claim 3, characterized in that, The number of the support structures includes two, and the two support structures are respectively located on opposite sides of the first current collector along the first direction.

7. The battery cell according to claim 6, characterized in that, The dimension of the second portion along the first direction is equal to half the dimension of the second electrode along the first direction.

8. The battery cell according to claim 3, characterized in that, The support structure is located on one side of the first current collector along the first direction.

9. The battery cell according to claim 8, characterized in that, The dimension of the second portion along the first direction is equal to the dimension of the second electrode along the first direction.

10. The battery cell according to claim 3, characterized in that, The second electrode tab protrudes from the edge of the second electrode body, and the second portion has an opening, through which the second electrode tab protrudes from the recess.

11. The battery cell according to claim 1, characterized in that, The first electrode is a positive electrode.

12. The battery cell according to claim 1, characterized in that, The surface of the second electrode is provided with a solid electrolyte layer, which covers the main body of the second electrode and at least part of the second tab.

13. A battery device, characterized in that, Includes the battery cell as described in any one of claims 1 to 12.

14. An electrical appliance, characterized in that, Includes the battery device as described in claim 13, the battery device being used to provide electrical energy.

Images