Battery cell, battery device, and electric device

Abstract

Provided in the present application are a battery cell, a battery device, and an electric device. The battery cell comprises a housing and an electrode assembly. The electrode assembly is accommodated in the housing, and comprises a first electrode sheet, a solid electrolyte layer, and a second electrode sheet that are sequentially stacked. The first electrode sheet comprises a first current collector and a first active material layer, the first active material layer being disposed on the side of the first current collector facing the solid electrolyte layer in a first direction. The electrode assembly further comprises a first insulating member, wherein the first insulating member is connected to the first current collector and the solid electrolyte layer, and the first current collector, the first insulating member and the solid electrolyte layer together define a first accommodating space for accommodating the first active material layer. By accommodating the first active material layer in the first accommodating space, the first active material layer is less likely to separate from the first accommodating space, thereby reducing the risk of the first active material layer coming into contact with the second electrode sheet, and improving the reliability of the battery cell.

Description

Battery cells, battery packs and electrical devices Cross-references to related applications

[0001] This application claims priority to Chinese patent application 202422608282.5, filed on October 28, 2024, entitled “Battery cell, battery device and power consumption device”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery technology, and in particular to a battery cell, battery device, and power supply device. Background Technology

[0003] Energy conservation and emission reduction are key to the sustainable development of the automotive industry, and electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of this sustainable development. For electric vehicles, battery technology is a crucial factor in their development.

[0004] Battery devices are widely used in portable electronic devices, electric vehicles, power tools, drones, energy storage devices, and other fields. With the increasing demand for batteries, higher requirements are being placed on the reliability of individual battery cells. Therefore, improving the reliability of individual battery cells is a pressing issue that needs to be addressed in battery technology. Summary of the Invention

[0005] This application provides a battery cell, a battery device, and an electrical device, which can improve the reliability of the battery cell.

[0006] In a first aspect, embodiments of this application provide a battery cell, including a casing and an electrode assembly; the electrode assembly is housed within the casing, and the electrode assembly includes a first electrode, a solid electrolyte layer, and a second electrode stacked together, the first electrode and the second electrode having opposite polarities, at least a portion of the solid electrolyte layer being disposed between the first electrode and the second electrode along a first direction, the first electrode including a first current collector and a first active material layer, the first active material layer being disposed on the side of the first current collector facing the solid electrolyte layer along the first direction; wherein, the electrode assembly further includes a first insulating member, the first insulating member being disposed around the outer edge of the first active material layer and connecting the first current collector and the solid electrolyte layer, the first current collector, the first insulating member, and the solid electrolyte layer jointly defining a first accommodating space, the first active material layer being housed within the first accommodating space.

[0007] In the above technical solution, the first current collector, the first insulating element, and the solid electrolyte layer jointly define the first accommodating space, and the first active material layer is accommodated within the first accommodating space. The first accommodating space can restrict the position of the first active material layer. The first insulating element connects the first current collector and the solid electrolyte layer. The first insulating element forms a sealing area in both the connection area with the first current collector and the connection area with the solid electrolyte layer. The first active material layer is not easy to detach from the sealing area of ​​the first accommodating space, thereby reducing the risk of the first active material layer detaching from the first accommodating space and contacting the second electrode, thereby reducing the risk of short circuits in the electrode assembly and improving the reliability of the battery cell.

[0008] In some embodiments, the solid electrolyte layer includes an extension region that extends beyond the outer edge of the first active material layer. This extension region, in conjunction with a first current collector, clamps the first insulating member. By providing an extension region that extends beyond the outer edge of the first active material layer, on the one hand, the solid electrolyte layer can further separate the first active material layer and the second electrode, thereby reducing the risk of contact between the first active material layer and the second electrode and improving the reliability of the battery cell; on the other hand, a larger solid electrolyte layer facilitates ion transport between the first and second electrodes, which is beneficial for improving the charge-discharge performance of the battery cell. Furthermore, the extension region, in conjunction with the first current collector, clamps the first insulating member, and the extension region and the first current collector can restrict the position of the first insulating member, improving the structural stability of the electrode assembly.

[0009] In some embodiments, the solid electrolyte layer further includes a main region, which is stacked with the first active material layer. The main region has a first surface facing the first active material layer, and the first active material layer is attached to the first surface. A portion of the extended region protrudes from the first surface along the direction from the solid electrolyte layer to the first current collector. By providing a portion of the extended region protruding from the first surface, on the one hand, the extended region protrudes from the first surface, allowing the solid electrolyte layer to encapsulate a portion of the first active material layer, thereby increasing the encapsulation effect between the first active material layer and the solid electrolyte layer, and enhancing the confinement effect of the solid electrolyte layer on the first active material layer, making the position of the first active material layer more stable. On the other hand, the extended region protruding from the first surface enhances the clamping effect of the extended region and the first current collector on the first insulating member, making the position of the first insulating member more stable and improving the structural stability of the electrode assembly.

[0010] In some embodiments, along the first direction, the thickness of the first active material layer is L1, and the thickness of the first insulating member is L2, where 0.5 ≤ L2 / L1 < 1. When L2 / L1 ≥ 0.5, the insulation effect of the first insulating member can be improved, reducing the risk of insulation failure. When L2 / L1 < 1, the thickness of the first active material layer is greater than the thickness of the first insulating member, which helps to reduce the risk of interference between the first insulating member and the first active material layer during the pressing and molding process. Therefore, when 0.5 ≤ L2 / L1 < 1, both the insulation effect of the first insulating member and the risk of interference between the first insulating member and the pressing and molding process of the first active material layer can be balanced.

[0011] In some embodiments, the first insulating member has a second surface facing away from the first current collector, and the extended region covers the second surface. By covering the second surface with the extended region, the contact area between the extended region and the second surface can be increased, improving the connection effect between the extended region and the first insulating member, and making the position of the first insulating member more stable.

[0012] In some embodiments, the first insulating member has a third surface facing the first current collector, and the first current collector covers the third surface. By having the first current collector cover the third surface, the contact area between the first current collector and the third surface can be increased, the connection effect between the first current collector and the third surface can be improved, and the position of the first insulating member can be made more stable.

[0013] In some embodiments, the first insulating member has a second surface facing away from the first current collector, and an extended region covers the second surface; the first insulating member also has a third surface facing the first current collector, and the first current collector covers the third surface. By having the extended region cover the second surface and the first current collector cover the third surface, the contact area between the extended region and the second surface, as well as the contact area between the first current collector and the third surface, can be increased, making the first current collector and the extended region more stable in clamping the first insulating member.

[0014] In some embodiments, in a projection plane perpendicular to the first direction, the projection of the extended area overlaps with the projection of the first insulating member, and the width of the overlap area is 1mm-5mm. When the width of the overlap area is greater than or equal to 1mm, sufficient connection strength can be achieved between the extended area and the first insulating member; when the width of the overlap area is less than or equal to 5mm, the installation difficulty of the first insulating member and the solid electrolyte layer can be reduced. Therefore, when the width of the overlap area is 1mm-5mm, it is possible to balance improving the connection strength between the extended area and the first insulating member and reducing the installation difficulty of the first insulating member and the solid electrolyte layer.

[0015] In some embodiments, the solid electrolyte layer has a first surface facing the first active material layer, the first active material layer is adhered to the first surface, and a part of the first insulating member protrudes from the first surface in the direction of the first current collector pointing to the solid electrolyte layer. By arranging a part of the first insulating member to protrude from the first surface in the direction of the first current collector pointing to the solid electrolyte layer, the thickness of a part of the first insulating member is greater than the thickness of the first active material layer, thereby reducing the risk that the first active material layer detaches from the first accommodation space.

[0016] In some embodiments, along the first direction, the thickness of the first active material layer is L1, and the thickness of the first insulating member is L2, where 1 < L2 / L1 ≤ 2. When L2 / L1 > 1, the thickness of the first insulating member can be made greater than the thickness of the first active material layer, reducing the risk that the first active material layer detaches from the first accommodation space; when L2 / L1 ≤ 2, the manufacturing difficulty of the first active material layer can be reduced, and the material usage of the first insulating member can be saved, thus saving the manufacturing cost; therefore, when 1 < L2 / L1 ≤ 2, it is possible to balance reducing the risk that the first active material layer detaches from the first accommodation space and reducing the manufacturing cost of the electrode assembly.

[0017] In some embodiments, along the first direction, the thickness of the first active material layer is L1, and the thickness of the first insulating member is L2, where 0.5 ≤ L2 / L1 ≤ 2. When 0.5 ≤ L2 / L1 < 1, it is possible to balance enhancing the insulation effect of the first insulating member and reducing the risk that the first insulating member interferes with the pressing and forming of the first active material layer; when L2 / L1 = 1, the thickness of the first insulating member is comparable to the thickness of the first active material layer, which is beneficial to the setting of the solid electrolyte layer; when 1 < L2 / L1 ≤ 2, it is possible to balance reducing the risk that the first active material layer escapes from the first insulating member and reducing the manufacturing cost of the electrode assembly.

[0018] In some embodiments, the first insulating member has an annular structure, and the wall thickness of the first insulating member is 1 mm - 5 mm. When the wall thickness of the first insulating member is greater than or equal to 1 mm, the strength of the first insulating member can be enhanced, reducing the risk of the first insulating member being damaged; when the wall thickness of the first insulating member is less than or equal to 5 mm, the material usage of the first insulating member can be saved, reducing the space occupied by the first insulating member; therefore, when the wall thickness of the first insulating member is 1 mm - 5 mm, it is possible to balance reducing the risk of the first insulating member being damaged and saving the material usage of the first insulating member.

[0019] In some embodiments, the thickness of the solid electrolyte layer along the first direction is 10 μm-50 μm. When the thickness of the solid electrolyte layer is greater than or equal to 10 μm, the strength of the solid electrolyte layer can be improved, and the risk of the solid electrolyte layer being damaged can be reduced; when the thickness of the solid electrolyte layer is less than or equal to 50 μm, the space occupied by the solid electrolyte layer in the electrode assembly can be reduced, thereby improving the volumetric energy density of the electrode assembly; therefore, when the thickness of the solid electrolyte layer is 10 μm-50 μm, it is possible to balance reducing the risk of solid electrolyte layer damage and improving the volumetric energy density of the electrode assembly.

[0020] In some embodiments, the second electrode includes a second current collector and a second active material layer. Along a first direction, the second active material layer is disposed on the side of the second current collector facing the solid electrolyte layer. By disposing the first and second active material layers on opposite sides of the solid electrolyte layer and placing the first active material layer within a first accommodating space, the risk of the first active material layer contacting the second active material layer can be reduced, thereby improving the reliability of the battery cell.

[0021] In some embodiments, the first electrode is a negative electrode and the second electrode is a positive electrode. In a projection plane perpendicular to the first direction, the projection of the second active material layer lies within the projection of the first active material layer, and the projected area of ​​the second active material layer is smaller than the projected area of ​​the first active material layer. Thus, the active material layer of the positive electrode is smaller than that of the negative electrode, making it easier for ions extracted from the positive electrode's active material layer to be received by the negative electrode's active material layer. This facilitates ion exchange between the positive and negative electrodes and extends the lifespan of the battery cell.

[0022] In some embodiments, in a projection plane perpendicular to the first direction, the minimum distance between the projection of the outer edge of the second active material layer and the projection of the outer edge of the first active material layer is 0mm-5mm. When the minimum distance between the projection of the outer edge of the second active material layer and the projection of the outer edge of the first active material layer is greater than or equal to 0mm, it can promote the first active material layer to receive ions extracted from the second active material layer, thus extending the life of the battery cell; when the minimum distance between the projection of the outer edge of the second active material layer and the projection of the outer edge of the first active material layer is less than or equal to 5mm, it can increase the amount of material used in the second active material layer, thereby increasing the capacity of the battery cell.

[0023] In some embodiments, the electrode assembly further includes a second insulating member disposed around the outer edge of the second active material layer and connecting the second current collector and the solid electrolyte layer. The second current collector, the second insulating member, and the solid electrolyte layer together define a second accommodating space, within which the second active material layer is accommodated. By providing the second insulating member, the second current collector, and the solid electrolyte layer to form the second accommodating space, and accommodating the second active material layer within the second accommodating space, the risk of the second active material layer contacting the first active material layer can be further reduced, thereby improving the reliability of the battery cell.

[0024] In some embodiments, the second insulating element is an annular structure, and the second accommodating space is a closed space. In this way, the second accommodating space seals the second active material layer, making it less likely for the second active material layer to detach from the second accommodating space, thereby further reducing the risk of the second active material layer contacting the first electrode and improving the reliability of the battery cell.

[0025] In some embodiments, the first insulating element is a ring structure, and the first accommodating space is a closed space. This makes it less likely for the first active material layer to detach from the first accommodating space, further reducing the risk of the first active material layer contacting the second electrode and improving the reliability of the battery cell.

[0026] Secondly, embodiments of this application provide a battery device, including the battery cell provided in any one of the embodiments of the first aspect.

[0027] Thirdly, embodiments of this application provide an electrical device, including a battery cell provided in any one of the embodiments of the first aspect or a battery device provided in any one of the embodiments of the second aspect, wherein the battery cell is used to provide electrical energy to the electrical device.

[0028] 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

[0029] 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 the drawings without creative effort.

[0030] Figure 1 is a structural schematic diagram of a vehicle provided in some embodiments of this application;

[0031] Figure 2 is an exploded view of a battery device provided in some embodiments of this application;

[0032] Figure 3 is an exploded view of a single battery cell provided in some embodiments of this application;

[0033] Figure 4 is a schematic diagram of the structure of a battery cell provided in some embodiments of this application;

[0034] Figure 5 is a cross-sectional view AA of Figure 4;

[0035] Figure 6 is a magnified view of a portion of region A in Figure 5;

[0036] Figure 7 is a schematic diagram of the structure of an electrode assembly provided in some embodiments of this application;

[0037] Figure 8 is a magnified view of region B in Figure 7;

[0038] Figure 9 is a CC cross-sectional view of Figure 7;

[0039] Figure 10 is a schematic diagram of the structure of an electrode assembly provided in some embodiments of this application;

[0040] Figure 11 is a magnified view of region C in Figure 10;

[0041] Figure 12 is a schematic diagram of the structure of an electrode assembly provided in some other embodiments of this application.

[0042] Labeling Explanation: 1-Electrode assembly; 11-First electrode; 111-First current collector; 112-First active material layer; 12-Solid electrolyte layer; 121-Excess area; 122-Main area; 1221-First surface; 1222-Fourth surface; 13-Second electrode; 131-Second current collector; 132-Second active material layer; 14-First insulator; 141-Second surface; 142-Third surface; 15-First receiving space; 16-Second insulator; 17-Second receiving space; 2-Outer shell; 21-Housing shell; 22-End cap; 3-Electrode terminal; 10-Battery cell; 20-Box; 100-Battery assembly; 201-First box; 202-Second box; 200-Controller; 300-Motor; 1000-Vehicle; X-First direction. Detailed Implementation

[0043] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of this application by way of example, but should not be used to limit the scope of this application, that is, this application is not limited to the described embodiments.

[0044] 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.

[0045] 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 indicating the number, specific order, or primary and secondary relationship of the indicated technical features.

[0046] 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.

[0047] 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), unless otherwise explicitly specified.

[0048] 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.

[0049] In this application, "multiple" refers to two or more (including two), and similarly, "multiple groups" refers to two or more (including two), and "multiple pieces" refers to two or more (including two).

[0050] 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.

[0051] Battery cells include, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0052] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. 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, reduces the risk of short circuits while allowing active ions to pass through.

[0053] In some embodiments, the positive electrode can be a positive electrode sheet, which may include a positive current collector and a positive active material disposed on at least one surface of the positive current collector.

[0054] 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.

[0055] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors 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 a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0056] 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 positive electrode active materials in battery cells 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 manganese iron phosphate, and lithium manganese iron phosphate and carbon composites. Examples of lithium transition metal oxides may include, but are not limited to, at least one of lithium cobalt oxides (such as LiCoO2), lithium nickel oxides (such as LiNiO2), lithium manganese oxides (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxides, lithium manganese cobalt oxides, lithium nickel manganese oxides, lithium nickel cobalt manganese oxides (such as LiNi1 / 3Col / 3Mn1 / 3O2 (also abbreviated as NCM333), LiNi0.5Co0.2Mn0.3O2 (also abbreviated as NCM523), LiNi0.5Co0.25Mn0.25O2 (also abbreviated as NCM211), LiNi0.6Co0.2Mn0.2O2 (also abbreviated as NCM622), LiNi0.8Co0.1Mn0.1O2 (also abbreviated as NCM811), lithium nickel cobalt aluminum oxides (such as LiNi0.85Co0.15Al0.05O2)) and their modified compounds.

[0057] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, 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 a lithium-rich material.

[0058] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative current collector.

[0059] As an example, the negative electrode current collector can be a metal foil, a foamed metal, or a composite current collector. For example, as a metal foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium, etc. Foamed metal can be nickel foam, copper foam, aluminum foam, foam alloy, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors 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 a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0060] As an example, the negative electrode sheet may include a negative current collector and a negative active material disposed on at least one surface of the negative current collector.

[0061] 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.

[0062] 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 in battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0063] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0064] 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.

[0065] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0066] 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.

[0067] As an example, inorganic solid electrolytes may include 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 phosphate sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0068] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0069]

[0070] 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.

[0071] 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 battery cells, such as hexagonal prismatic battery cells.

[0072] 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, which are connected in series, parallel, or mixed connections via a busbar.

[0073] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging multiple battery cells and fixing them together to form an independent module.

[0074] As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0075] In some embodiments, the battery device may be a battery pack, which may include a housing and one or more individual battery cells housed within the housing.

[0076] 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.

[0077] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0078] 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.

[0079] 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.

[0080] As an example, the housing can be part of the vehicle's chassis structure. For instance, the housing's roof can be at least part of the vehicle's floor, or the housing's frame can be at least part of the vehicle's crossbeams and longitudinal beams.

[0081] In some embodiments, the battery device refers to an energy storage device, which includes a housing with a door on at least one side. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0082] For a typical battery cell, the battery cell may include a casing and an electrode assembly. The electrode assembly is housed within the casing and may include a first electrode, a separator, and a second electrode. The first electrode and the second electrode have opposite polarities. The separator is disposed between the first electrode and the second electrode to separate them. The first electrode includes a first current collector and a first active material layer. The first active material layer is disposed on the side of the first current collector facing the separator.

[0083] In a solid-state battery cell, the solid electrolyte layer serves as a separator between the first and second electrodes. Although the solid electrolyte layer effectively separates the first and second electrodes, the first active material layer is exposed within the electrode assembly. During the production and use of the battery cell, there remains a risk that the first active material layer may come into contact with the second electrode. For example, during the manufacturing process, a pressing process is required between the solid electrolyte layer and the first current collector. During this pressing process, the first active material layer can easily be squeezed out of the solid electrolyte layer and come into contact with the second electrode, leading to an internal short circuit within the battery cell and affecting its reliability.

[0084] In view of this, in order to improve the reliability of the battery cell, this application provides a battery cell including a casing and an electrode assembly. The electrode assembly is housed within the casing and includes a first electrode, a solid electrolyte layer, and a second electrode stacked together. The first electrode and the second electrode have opposite polarities. At least a portion of the solid electrolyte layer is disposed between the first electrode and the second electrode along a first direction. The first electrode includes a first current collector and a first active material layer. Along the first direction, the first active material layer is disposed on the side of the first current collector facing the solid electrolyte layer. The electrode assembly also includes a first insulating member, which surrounds the outer edge of the first active material layer and connects the first current collector and the solid electrolyte layer. The first current collector, the first insulating member, and the solid electrolyte layer together define a first accommodating space, and the first active material layer is housed within the first accommodating space.

[0085] In such a battery cell, the first active material layer is housed within a first containment space. The first containment space restricts the position of the first active material layer, reducing the risk of the first active material layer contacting the second electrode. The first current collector and the solid electrolyte layer are connected by a first insulating member. The connection area between the first insulating member and the first current collector, as well as the connection area between the first insulating member and the solid electrolyte layer, both form sealed areas. The first active material layer is less likely to detach from the sealed area and the first containment space, thereby further reducing the risk of the first active material layer contacting the second electrode and improving the reliability of the battery cell.

[0086] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery cells and battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft.

[0087] For ease of explanation, the following embodiments use a vehicle as an example of electrical equipment.

[0088] Please refer to Figure 1, which is a structural schematic diagram of a vehicle 1000 provided in some embodiments of this application. A battery device 100 is disposed inside the vehicle 1000, and the battery device 100 may be located 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.

[0089] The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, for the power needs of the vehicle 1000 during startup, navigation and driving.

[0090] In some embodiments of this application, the battery device 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.

[0091] Please refer to Figure 2, which is an exploded view of a battery device 100 provided in some embodiments of this application. The battery device 100 may include a housing 20 and battery cells 10, with the housing 20 used to house the battery cells 10.

[0092] The housing 20 has an enclosed space inside for accommodating the battery cells 10. The housing 20 can have various structures. In some embodiments, the housing 20 may include a first housing 201 and a second housing 202, which are interlocked. The first housing 201 and the second housing 202 can have various shapes, such as cuboids or cylinders. The first housing 201 can be a hollow structure open on one side, and the second housing 202 can also be a hollow structure open on one side. The open side of the second housing 202 interlocks with the open side of the first housing 201, thus forming a housing 20 with an enclosed space. Alternatively, the first housing 201 can be a hollow structure open on one side, and the second housing 202 can be a plate-like structure, with the second housing 202 interlocked with the open side of the first housing 201, thus forming a housing 20 with an accommodating space.

[0093] In the battery device 100, there can be one or more battery cells 10. If there are multiple battery cells 10, they can be connected in series, parallel, or in a mixed manner. A mixed connection means that multiple battery cells 10 are connected in both series and parallel. Alternatively, multiple battery cells 10 can be first connected in series, parallel, or in a mixed manner to form a battery module, and then multiple battery modules can be connected in series, parallel, or in a mixed manner to form a whole, which is then housed within the housing 20. Another option is that all battery cells 10 can be directly connected in series, parallel, or in a mixed manner, and then the whole consisting of all battery cells 10 is housed within the housing 20.

[0094] Please refer to Figure 3, which is an exploded view of a battery cell 10 provided in some embodiments of this application. The battery cell 10 may include an electrode assembly 1 and a housing 2, with the electrode assembly 1 housed within the housing 2.

[0095] In some embodiments, the housing 2 may include a housing 21 and an end cap 22, the housing 21 having an opening, and the end cap 22 closing the opening of the housing 21. Here, "closed" means covered or shut off, and can be either sealed or unsealed.

[0096] The housing 21 is a component used to house the electrode assembly 1. The housing 21 can be a hollow structure with an opening at one end, or it can be a hollow structure with openings at both opposite ends. The housing 21 can have various shapes, such as cylindrical or cuboid. The housing 21 can be made of various materials, such as copper, iron, aluminum, steel, or aluminum alloy. The electrode assembly 1 can be partially or completely located within the housing 21.

[0097] End cap 22 and housing 21 together define a receiving space for accommodating electrode assembly 1 and other components. End cap 22 can be connected to housing 21 by welding, rolling, or other methods to close the opening of housing 21. The shape of end cap 22 can be adapted to the shape of housing 21. For example, if housing 21 is a cuboid structure, end cap 22 can be a rectangular plate structure adapted to housing 21; or if housing 21 is a cylindrical structure, end cap 22 can be a circular plate structure adapted to housing 21. The material of end cap 22 can also be various, such as copper, iron, aluminum, steel, aluminum alloy, etc. The materials of end cap 22 and housing 21 can be the same or different.

[0098] In an embodiment where the housing 21 has an opening at one end, one end cap 22 may be provided. In an embodiment where the housing 21 has openings at both opposite ends, two end caps 22 may be provided, with the two end caps 22 respectively closing the two openings of the housing 21, and the two end caps 22 and the housing 21 together defining the receiving space.

[0099] In some embodiments, the battery cell 10 may further include electrode terminals 3, which are disposed on the housing 2. The electrode terminals 3 are used for electrical connection with the tabs of the electrode assembly 1 to input or output electrical energy from the battery cell 10. The electrode terminals 3 may be disposed on the housing 21 of the housing 2 or on the end cap 22 of the housing 2. The electrode terminals 3 and the tabs may be directly connected, for example, by welding the electrode terminals 3 to the tabs. The electrode terminals 3 and the tabs may also be indirectly connected, for example, by a current collector. The current collector may be a metallic conductor, such as copper, iron, aluminum, steel, or aluminum alloy.

[0100] Please refer to Figures 4 and 5. Figure 4 is a structural schematic diagram of a battery cell 10 provided in some embodiments of this application; Figure 5 is a cross-sectional view AA of Figure 4. This application provides a battery cell 10, including a housing 2 and an electrode assembly 1. The electrode assembly 1 is housed within the housing 2. The electrode assembly 1 includes a first electrode 11, a solid electrolyte layer 12, and a second electrode 13 stacked together. The first electrode 11 and the second electrode 13 have opposite polarities. At least a portion of the solid electrolyte layer 12 is disposed between the first electrode 11 and the second electrode 13 along a first direction X. The first electrode 11 includes a first current collector 111 and a first active material layer 112. Along the first direction X, the first active material layer 112 is disposed on the side of the first current collector 111 facing the solid electrolyte layer 12. The electrode assembly 1 further includes a first insulating member 14, which surrounds the outer edge of the first active material layer 112 and connects the first current collector 111 and the solid electrolyte layer 12. The first current collector 111, the first insulating member 14 and the solid electrolyte layer 12 together define a first accommodating space 15, in which the first active material layer 112 is accommodated.

[0101] The first electrode 11 can be the positive electrode, the second electrode 13 can be the negative electrode, and the first active material layer 112 can be the positive active material; or the first electrode 11 can be the negative electrode, the second electrode 13 can be the positive electrode, and the second active material layer 132 can be the negative active material.

[0102] It is possible that only a portion of the solid electrolyte layer 12 is disposed between the first electrode 11 and the second electrode 13; or it is possible that the entire solid electrolyte layer 12 is disposed between the first electrode 11 and the second electrode 13.

[0103] The first active material layer 112 may be provided on only one side of the first current collector 111, and a solid electrolyte layer 12 may be provided on the side of the first active material layer 112 facing away from the first current collector 111; or the first active material layer 112 may be provided on both opposite sides of the first current collector 111, and a solid electrolyte layer 12 may be provided on the side of one first active material layer 112 facing away from the first current collector 111, and a solid electrolyte layer 12 may also be provided on the side of the other first active material layer 112 facing away from the first current collector 111.

[0104] The first insulating member 14 is disposed around the outer edge of the first active material layer 112, such that the first active material layer 112 is located inside the first insulating member 14. Alternatively, the first insulating member 14 may be a ring structure, with the first active material layer 112 located inside the ring structure. Or, the first insulating member 14 may include multiple insulating portions disposed around the outer edge of the first active material layer 112; wherein the multiple insulating portions may be connected or spaced apart.

[0105] The projection of the outer edge of the first active material layer 112 along the first direction X can be circular, polygonal, or similar. The projection shape of the first insulating member 14 along the first direction X can be the same as or different from that of the first active material layer 112. The first insulating member 14 is made of an insulating material, such as polyimide, polyetheretherketone, polyphenylene sulfide, silicone rubber, etc. The first direction X is parallel to the thickness direction of the first current collector 111.

[0106] The first insulating member 14 connects the first current collector 111 and the solid electrolyte layer 12. It can be that the first insulating member 14 is bonded or abutted to the first current collector 111, or the first insulating member 14 is bonded or abutted to the solid electrolyte layer 12.

[0107] The first insulating member 14 can connect the first current collector 111 and the solid electrolyte layer 12 to form a sealed structure. For example, the first insulating member 14 can be annular, with the connection area between the first insulating member 14 and the first current collector 111 forming an annular sealed area, and the connection area between the first insulating member 14 and the solid electrolyte layer 12 also forming an annular sealed area. These two annular sealed areas isolate the first accommodating space 15 from the outside. Alternatively, the first insulating member 14 can connect the first current collector 111 and the solid electrolyte layer 12 to form a non-sealed structure. For example, the first insulating member 14 can include multiple spaced insulating portions surrounding the first active material layer 112. Each insulating portion connects the first current collector 111 and the solid electrolyte layer 12, with gaps between adjacent insulating portions, allowing the first accommodating space 15 to communicate with the outside. It is understood that the first accommodating space 15 can be a sealed space or it can be open to the outside.

[0108] In this embodiment, a first accommodating space 15 is defined by the first current collector 111, the first insulating member 14, and the solid electrolyte layer 12. The first active material layer 112 is accommodated within the first accommodating space 15, which restricts the position of the first active material layer 112. During the manufacturing process of the battery cell 10, the first active material layer 112 coated on the first current collector 111 can be pressed to shape the first active material layer 112 and densify the active material of the first active material layer 112, thereby reducing the volume of the first active material layer 112 and improving the conductivity between the active materials. Pressing also makes the connection between the first active material layer 112 and the solid electrolyte layer 12 tighter, which can promote the ion conduction capability between the first active material layer 112 and the solid electrolyte layer 12. By accommodating the first active material layer 112 within the first accommodating space 15, during the pressing process, the first current collector 111 and the solid electrolyte layer 12 are connected by the first insulating member 14. The first insulating member 14 forms a sealing area in both the connection area with the first current collector 111 and the connection area with the solid electrolyte layer 12. The first active material layer 112 is less likely to detach from the sealing area into the first accommodating space 15, thereby reducing the risk of the first active material layer 112 detaching from the first accommodating space 15 and contacting the second electrode 13, thereby reducing the risk of short circuit within the electrode assembly 1 and improving the reliability of the battery cell 10.

[0109] In some embodiments, please refer to Figures 4-6, where Figure 6 is a partial enlarged view of region A in Figure 5. The solid electrolyte layer 12 includes an overhang region 121 that extends beyond the outer edge of the first active material layer 112. The overhang region 121 cooperates with the first current collector 111 to clamp the first insulating member 14.

[0110] The extended region 121 extends beyond the outer surface of the first active material layer 112, that is, along the first direction X, the projection of the extended region 121 is located outside the projection of the first active material layer 112.

[0111] It can be the entirety of the first insulating member 14 that is clamped by the first current collector 111 beyond the area 121; or it can be only a portion of the first insulating member 14 that is clamped by the first current collector 111 beyond the area 121.

[0112] By providing the extended region 121, the connection between the first insulating member 14 is facilitated, reducing the installation difficulty of the solid electrolyte layer 12 and the first insulating member 14. By extending the extended region 121 beyond the outer edge of the first active material layer 112, on the one hand, the solid electrolyte layer 12 can further separate the first active material layer 112 and the second electrode 13, thereby reducing the risk of contact between the first active material layer 112 and the second electrode 13 and improving the reliability of the battery cell 10; on the other hand, a larger solid electrolyte layer 12 facilitates ion transport between the first electrode 11 and the second electrode 13, which is beneficial to improving the charge and discharge performance of the battery cell 10. Furthermore, the extended region 121, in conjunction with the first current collector 111, clamps the first insulating member 14, and the extended region 121 and the first current collector 111 can restrict the position of the first insulating member 14, improving the structural stability of the electrode assembly 1.

[0113] In some embodiments, please continue to refer to Figures 4-6. The solid electrolyte layer 12 also includes a main body region 122, which is stacked with the first active material layer 112. The main body region has a first surface 1221 facing the first active material layer 112. The first active material layer 112 is laminated to the first surface 1221. The extended region 121 partially protrudes from the first surface 1221 in the direction of the solid electrolyte layer 12 pointing to the first current collector 111.

[0114] Along the first direction X, the projection of the main body region 122 lies within the projection of the first active material layer 112. The first surface 1221 faces the first active material layer 112, and the first active material layer 112 is in contact with the first surface 1221. Ion exchange between the first active material layer 112 and the solid electrolyte layer 12 can be achieved through the contact area between the first surface 1221 and the first active material layer 112. The extended region 121 partially protrudes from the first surface 1221, such that a portion of the first active material layer 112 is further away from the first current collector 111 than a portion of the extended region 121. The first surface 1221 can be planar or curved.

[0115] By setting the extended region 121 to partially protrude from the first surface 1221, on the one hand, the extended region 121 partially protruding from the first surface 1221 allows the solid electrolyte layer 12 to wrap a portion of the first active material layer 112 in the direction of the first current collector 111, thereby increasing the wrapping effect of the first active material layer 112 on the solid electrolyte layer 12 and improving the restraining effect of the solid electrolyte layer 12 on the first active material layer 112, making the position of the first active material layer 112 more stable; on the other hand, the extended region 121 partially protruding from the first surface 1221 can improve the clamping effect of the extended region 121 and the first current collector 111 on the first insulating member 14, making the position of the first insulating member 14 more stable and improving the structural stability of the electrode assembly 1; furthermore, the extended region 121 protruding from the first surface 1221 in the direction pointing to the first current collector 111 can reduce the size of the first insulating member 14 along the first direction X, thereby saving the material used in the first insulating member 14 and saving the material cost of the first insulating member 14.

[0116] In some embodiments, please continue to refer to Figure 6. Along the first direction X, the thickness of the first active material layer 112 is L1, the thickness of the first insulating member 14 is L2, and 0.5 ≤ L2 / L1 < 1.

[0117] The thickness of the first insulating element 14 is less than the thickness of the first active material layer 112. L2 / L1 can be any point value or a range between any two of the following: 0.5, 0.53, 0.55, 0.58, 0.6, 0.63, 0.65, 0.68, 0.7, 0.73, 0.75, 0.78, 0.8, 0.83, 0.85, 0.88, 0.9, 0.93, 0.95, 0.98, 0.999. For example, the thickness of the first active material layer 112 is 10 μm, and the thickness of the first insulating element 14 can be 8 μm.

[0118] In this embodiment, when L2 / L1≥0.5, the insulation effect of the first insulating member 14 can be improved, reducing the risk of insulation failure. When L2 / L1<1, the thickness of the first active material layer 112 is greater than the thickness of the first insulating member 14, which helps to reduce the risk of interference between the first insulating member 14 and the first active material layer 112 during the pressing process. Therefore, when 0.5≤L2 / L1<1, both the insulation effect of the first insulating member 14 and the risk of interference between the first insulating member 14 and the first active material layer 112 during pressing can be balanced. During the pressing process of the first active material layer 112 and the solid electrolyte layer 12, the thickness of the first active material layer 112 being greater than the thickness of the first insulating member 14 makes it easier for the solid electrolyte layer 12 to contact the first active material layer 112, which is beneficial to the implementation of the pressing process.

[0119] In some embodiments, please continue to refer to Figures 5 and 6. The first insulating member 14 has a second surface 141 facing away from the first current collector 111, and the extended region 121 covers the second surface 141.

[0120] Along the first direction X, the projection of the extended region 121 may completely overlap with the projection of the second surface 141; alternatively, the projection of the second surface 141 may lie within the projection of the extended region 121, and the projected area of ​​the extended region 121 may be larger than the projected area of ​​the second surface 141. The entire second surface 141 may be in contact with the extended region 121, or only a portion of the second surface 141 may be in contact with the extended region 121.

[0121] By covering the second surface 141 with the extended area 121, the contact area between the extended area 121 and the second surface 141 can be increased, the connection effect between the extended area 121 and the first insulating member 14 can be improved, and the position of the first insulating member 14 can be made more stable.

[0122] In some embodiments, please continue to refer to Figures 5 and 6. The first insulating member 14 has a third surface 142 facing the first current collector 111, and the first current collector 111 covers the third surface 142.

[0123] Along the first direction X, the projection of the third surface 142 lies within the projection of the first current collector 111.

[0124] The third surface 142 may be entirely attached to the first current collector 111, or only a portion of the third surface 142 may be attached to the first current collector 111.

[0125] By covering the third surface 142 with the first current collector 111, the contact area between the first current collector 111 and the third surface 142 can be increased, the connection effect between the first current collector 111 and the third surface 142 can be improved, and the position of the first insulating member 14 can be made more stable.

[0126] In some embodiments, the first insulating member 14 has a second surface 141 facing away from the first current collector 111, and the extended region 121 covers the second surface 141. The first insulating member 14 has a third surface 142 facing the first current collector 111, and the first current collector 111 covers the third surface 142.

[0127] Alternatively, the entire second surface 141 may be in contact with the area extending beyond 121, and the entire third surface 142 may be in contact with the first current collector 111. Or, the entire second surface 141 may be in contact with the area extending beyond 121, and only a portion of the third surface 142 may be in contact with the first current collector 111. Alternatively, only a portion of the second surface 141 may be in contact with the area extending beyond 121, and the entire third surface 142 may be in contact with the first current collector 111. Or, only a portion of the second surface 141 may be in contact with the area extending beyond 121, and only a portion of the third surface 142 may be in contact with the first current collector 111.

[0128] By covering the second surface 141 with the extended area 121 and the third surface 142 with the first current collector 111, the contact area between the extended area 121 and the second surface 141, as well as the contact area between the first current collector 111 and the third surface 142, can be increased, making the first current collector 111 and the extended area 121 cooperate to clamp the first insulating member 14 more stably.

[0129] In some embodiments, please continue to refer to Figures 5 and 6. In a projection plane perpendicular to the first direction X, the projection of the extended area 121 overlaps with the projection of the first insulating member 14, and the width of the overlap area is 1mm-5mm.

[0130] The width of the overlapping area is K1, which can be any point value or a range between any two of the following: 1mm, 1.3mm, 1.5mm, 1.8mm, 2mm, 2.3mm, 2.5mm, 2.8mm, 3mm, 3.3mm, 3.5mm, 3.8mm, 4mm, 4.3mm, 4.5mm, 4.8mm, and 5mm.

[0131] The width of the overlapping area is related to the maximum width of the first insulating element 14 and the maximum width of the extended area 121. When the minimum of the two is less than 5mm, the maximum width of the overlapping area is the minimum of the two. For example, if the maximum width of the insulating element is 3mm and the maximum width of the extended area 121 is 6mm, it can be understood that the maximum width of the overlapping area is 3mm.

[0132] When the width of the overlapping area is greater than or equal to 1 mm, sufficient connection strength can be achieved between the overhang area 121 and the first insulating member 14; when the width of the overlapping area is less than or equal to 5 mm, the installation difficulty of the first insulating member 14 and the solid electrolyte layer 12 can be reduced; therefore, when the width of the overlapping area is 1 mm to 5 mm, it is possible to balance improving the connection strength between the overhang area 121 and the first insulating member 14 and reducing the installation difficulty of the first insulating member 14 and the solid electrolyte layer 12.

[0133] In some embodiments, please refer to Figures 7 and 8. Figure 7 is a structural schematic diagram of the electrode assembly 1 provided in some embodiments of this application; Figure 8 is a partial enlarged view of region B in Figure 7. The solid electrolyte layer 12 has a first surface 1221 facing the first active material layer 112, the first active material layer 112 is attached to the first surface 1221, and a portion of the first insulating member 14 protrudes from the first surface 1221 along the direction of the first current collector 111 pointing towards the solid electrolyte layer 12.

[0134] Along the first direction X, the projection of the main body region 122 lies within the projection of the first active material layer 112. The first surface 1221 is disposed facing the first active material layer 112, and the first active material layer 112 is attached to the first surface 1221. Ion exchange between the first active material layer 112 and the solid electrolyte layer 12 can be achieved through the attachment area of ​​the first surface 1221 and the first active material layer 112.

[0135] A portion of the first insulating member 14 protrudes from the first surface 1221 along the direction from the first current collector 111 toward the solid electrolyte layer 12, such that the first active material layer 112 is closer to the first current collector 111 than a portion of the first insulating member 14. The first surface 1221 can be a plane or a curved surface.

[0136] By setting a portion of the first insulating member 14 to protrude from the first surface 1221 along the direction of the first current collector 111 toward the solid electrolyte layer 12, the thickness of a portion of the first insulating member 14 is greater than the thickness of the first active material layer 112, thereby reducing the risk of the first active material layer 112 detaching from the first containment space 15.

[0137] In some embodiments, please continue to refer to Figure 8. Along the first direction X, the thickness of the first active material layer 112 is L1, the thickness of the first insulating member 14 is L2, and 1L2 / L1≤2.

[0138] The thickness of the first insulating element 14 is greater than the thickness of the first active material layer 112. L2 / L1 can be any point value or a range between any two of the following: 1.001, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2. For example, the thickness of the first active material layer 112 is 10 μm, and the thickness of the first insulating element 14 can be 12 μm.

[0139] In this embodiment, when L2 / L1 > 1, the thickness of the first insulating member 14 can be made greater than the thickness of the first active material layer 112, reducing the risk that the first active material layer 112 detaches from the first accommodating space 15; when L2 / L1 ≤ 2, the manufacturing difficulty of the first active material layer 112 can be reduced, the material usage of the first insulating member 14 can be saved, and the manufacturing cost can be saved; therefore, when 1 < L2 / L1 ≤ 2, it is possible to balance reducing the risk that the first active material layer 112 detaches from the first accommodating space 15 and reducing the manufacturing cost of the electrode assembly 1.

[0140] In some embodiments, along the first direction X, the thickness of the first active material layer 112 is L1, and the thickness of the first insulating member 14 is L2, where 0.5 ≤ L2 / L1 ≤ 2.

[0141] L2 / L1 can be a point value of any one of 0.5, 0.53, 0.55, 0.58, 0.6, 0.63, 0.65, 0.68, 0.7, 0.73, 0.75, 0.78, 0.8, 0.83, 0.85, 0.88, 0.9, 0.93, 0.95, 0.98, 1, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2 or a range value between any two of them.

[0142] In this embodiment, when 0.5 ≤ L2 / L1 < 1, it is possible to balance improving the insulation effect of the first insulating member 14 and reducing the risk that the first insulating member 14 interferes with the pressing and forming of the first active material layer 112; when L2 / L1 = 1, the thickness of the first insulating member 14 is equivalent to the thickness of the first active material layer 112, which is beneficial to the setting of the solid electrolyte layer 12; when 1 < L2 / L1 ≤ 2, it is possible to balance reducing the risk that the first active material layer 112 detaches from the first accommodating space 15 and reducing the manufacturing cost of the electrode assembly 1.

[0143] In some embodiments, please refer to FIG. 9, which is a C-C cross-sectional view of FIG. 7. The first insulating member 14 has an annular structure, and the wall thickness of the first insulating member 14 is 1 mm - 5 mm.

[0144] The thickness of the first insulating member 14 is the distance between the inner ring and the outer ring of the first insulating member 14. The thickness of the first insulating member 14 is H1, and H1 can be a point value of any one of 1 mm, 1.3 mm, 1.5 mm, 1.8 mm, 2 mm, 2.3 mm, 2.5 mm, 2.8 mm, 3 mm, 3.3 mm, 3.5 mm, 3.8 mm, 4 mm, 4.3 mm, 4.5 mm, 4.8 mm, 5 mm or a range value between any two of them.

[0145] In this embodiment, when the wall thickness of the first insulating member 14 is greater than or equal to 1 mm, the strength of the first insulating member 14 can be improved, and the risk of the first insulating member 14 being damaged can be reduced; when the wall thickness of the first insulating member 14 is less than or equal to 5 mm, the material used by the first insulating member 14 can be saved, and the space occupied by the first insulating member 14 can be reduced; therefore, when the wall thickness of the first insulating member 14 is 1 mm to 5 mm, the risk of the first insulating member 14 being damaged and the material used by the first insulating member 14 can be saved at the same time.

[0146] In some embodiments, please refer to Figure 6. Along the first direction X, the thickness of the solid electrolyte layer 12 is 10 μm-50 μm.

[0147] The main body region 122 of the solid electrolyte layer 12 has a first surface 1221 and a fourth surface 1222 disposed opposite to each other. The dimensions of the first surface 1221 and the fourth surface 1222 are equal to the thickness of the solid electrolyte layer 12. The thickness of the solid electrolyte layer 12 is H2, which can be any one of 10μm, 11μm, 13μm, 15μm, 17μm, 19μm, 20μm, 21μm, 23μm, 25μm, 27μm, 29μm, 30μm, 31μm, 33μm, 35μm, 37μm, 39μm, 40μm, 41μm, 43μm, 45μm, 47μm, 49μm, and 50μm, or a range between any two.

[0148] In this embodiment, when the thickness of the solid electrolyte layer 12 is greater than or equal to 10 μm, the strength of the solid electrolyte layer 12 can be improved, and the risk of the solid electrolyte layer 12 being damaged can be reduced. When the thickness of the solid electrolyte layer 12 is less than or equal to 50 μm, the space occupied by the solid electrolyte layer 1 can be reduced, thereby improving the volumetric energy density of the electrode assembly 1. Therefore, when the thickness of the solid electrolyte layer 12 is 10 μm-50 μm, it is possible to balance reducing the risk of the solid electrolyte layer 12 being damaged and improving the volumetric energy density of the electrode assembly 1.

[0149] In some embodiments, please refer to Figures 10 and 11. Figure 10 is a structural schematic diagram of the electrode assembly 1 provided in some embodiments of this application; Figure 11 is a partial enlarged view of region C in Figure 10. The second electrode 13 includes a second current collector 131 and a second active material layer 132. Along the first direction X, the second active material layer 132 is disposed on the side of the second current collector 131 facing the solid electrolyte layer 12.

[0150] The first electrode 11 and the second electrode 13 have opposite polarities. The first active material layer 112 can be a positive active material and the second active material layer 132 a negative active material; alternatively, the first active material layer 112 can be a negative active material and the second active material layer 132 a positive active material.

[0151] By disposing the first active material layer 112 and the second active material layer 132 on both sides of the solid electrolyte layer 12, and disposing the first active material layer 112 within the first accommodating space 15, the risk of the first active material layer 112 contacting the second active material layer 132 can be reduced, thereby improving the reliability of the battery cell 10.

[0152] In some embodiments, please continue to refer to Figures 10 and 11. The first electrode 11 is the negative electrode, and the second electrode 13 is the positive electrode. In the projection plane perpendicular to the first direction X, the projection of the second active material layer 132 lies within the projection of the first active material layer 112, and the projected area of ​​the second active material layer 132 is smaller than the projected area of ​​the first active material layer 112.

[0153] Along the first direction X, the projection of the positive electrode active material lies within the projection of the negative electrode active material, and the projected area of ​​the positive electrode active material is smaller than that of the negative electrode active material. Taking a lithium-ion battery cell 10 as an example, during charging of the battery cell 10, lithium ions in the positive electrode active material are easily deintercalated and inserted into the negative electrode active material after passing through the solid electrolyte layer 12 along the first direction X. The projected area of ​​the negative electrode active material along the first direction X is larger than that of the positive electrode active material along the first direction X, which is beneficial for lithium ions to be properly inserted into the negative electrode active material and reduces the risk of lithium plating in the electrode assembly 1.

[0154] In this embodiment, the projection of the second active material layer 132 is located within the projection of the first active material layer 112, and the projected area of ​​the second active material layer 132 is smaller than the projected area of ​​the first active material layer 112. The active material layer of the positive electrode is smaller than the active material layer of the negative electrode, which makes it easier for the ions deintercalated from the active material layer of the positive electrode to be received by the active material layer of the negative electrode, which is beneficial to the ion exchange between the positive and negative electrodes and extends the life of the battery cell 10.

[0155] In some embodiments, in a projection plane perpendicular to the first direction X, the minimum distance between the projection of the outer edge of the second active material layer 132 and the projection of the outer edge of the first active material layer 112 is 0mm-5mm.

[0156] The minimum distance between the projection of the outer edge of the second active material layer 132 and the projection of the outer edge of the first active material layer 112 can be any one of the following values ​​or any value between two values: 0mm, 0.1mm, 0.3mm, 0.5mm, 0.7mm, 0.9mm, 1mm, 1.3mm, 1.5mm, 1.8mm, 2mm, 2.3mm, 2.5mm, 2.8mm, 3mm, 3.3mm, 3.5mm, 3.8mm, 4mm, 4.3mm, 4.5mm, 4.8mm, and 5mm.

[0157] In this embodiment, when the minimum distance between the projection of the outer edge of the second active material layer 132 and the projection of the outer edge of the first active material layer 112 is greater than or equal to 0 mm, the first active material layer 112 can receive ions that have been inserted or removed from the second active material layer 132, thereby extending the lifespan of the battery cell 10; when the minimum distance between the projection of the outer edge of the second active material layer 132 and the projection of the outer edge of the first active material layer 112 is less than or equal to 5 mm, the amount of material used in the second active material layer 132 can be increased, thereby increasing the capacity of the battery cell 10.

[0158] In some embodiments, please refer to FIG12, which is a schematic diagram of the structure of an electrode assembly 1 provided in other embodiments of this application. The electrode assembly 1 further includes a second insulating member 16, which is disposed around the outer edge of the second active material layer 132 and connects the second current collector 131 and the solid electrolyte layer 12. The second current collector 131, the second insulating member 16 and the solid electrolyte layer 12 together define a second accommodating space 17, in which the second active material layer 132 is accommodated.

[0159] The second insulating member 16 is disposed around the outer edge of the second active material layer 132, such that the second active material layer 132 is located inside the second insulating member 16. Alternatively, the second insulating member 16 may be an annular structure, with the second active material layer 132 located inside the annular structure. Alternatively, the second insulating member 16 may include multiple insulating portions disposed around the outer edge of the second active material layer 132; wherein the multiple insulating portions may be connected or spaced apart.

[0160] The projection of the outer edge of the second active material layer 132 along the first direction X can be circular, polygonal, or the like. The projection shape of the second insulating member 16 along the first direction X can be the same as or different from that of the second active material layer 132. The material of the second insulating member 16 can be polyimide, polyetheretherketone, polyphenylene sulfide, silicone rubber, etc.

[0161] The second insulating member 16 connects the second current collector 131 and the solid electrolyte layer 12. It can be that the second insulating member 16 is bonded or abutted to the second current collector 131, or that the second insulating member 16 is bonded or abutted to the solid electrolyte layer 12.

[0162] The connection area between the second insulator 16 and the second current collector 131 can form an annular sealing area to seal both the second insulator 16 and the second current collector 131; alternatively, a gap can be provided between the second insulator 16 and the second current collector 131 to allow the second receiving space 17 to communicate with the outside. The connection area between the second insulator 16 and the solid electrolyte layer 12 can form an annular sealing area to seal both the second insulator 16 and the solid electrolyte layer 12; alternatively, a gap can be provided between the second insulator 16 and the solid electrolyte layer 12 to allow the second receiving space 17 to communicate with the outside.

[0163] It is understandable that the second containment space 17 can be a closed space or a space that is connected to the outside.

[0164] By setting the second insulating element 16 to form a second accommodating space 17 with the second current collector 131 and the solid electrolyte layer 12, and accommodating the second active material layer 132 in the second accommodating space 17, the risk of the second active material layer 132 coming into contact with the first active material layer 112 can be further reduced, thereby improving the reliability of the battery cell 10.

[0165] In some embodiments, the second insulating member 16 is a ring structure, and the second accommodating space 17 is a closed space.

[0166] The second insulating member 16 is disposed around the second active material layer 132, and the connection area between the second insulating member 16 and the second current collector 131 forms a sealed area, and the connection area between the second insulating member 16 and the solid electrolyte layer 12 also forms a sealed area, thereby isolating the second accommodating space 17 from the outside.

[0167] By setting the second containment space 17 as a sealed space, the second containment space 17 seals the second active material layer 132, making it less likely for the second active material layer 132 to detach from the second containment space 17, thereby further reducing the risk of the second active material layer 132 coming into contact with the first electrode 11 and improving the reliability of the battery cell 10.

[0168] In some embodiments, the first insulating element 14 is a ring structure, and the first accommodating space 15 is a closed space.

[0169] The first insulating member 14 is disposed around the first active material layer 112, and the connection area between the first insulating member 14 and the first current collector 111 forms a sealed area, and the connection area between the first insulating member 14 and the solid electrolyte layer 12 also forms a sealed area, thereby isolating the first accommodating space 15 from the outside.

[0170] In this embodiment, by enclosing the first active material layer 112 within a closed space, the first active material layer 112 is less likely to detach from the closed space, further reducing the risk of the first active material layer 112 contacting the second electrode 13 and improving the reliability of the battery cell 10.

[0171] This application provides a battery device 100, which includes a battery cell 10 provided in any of the above embodiments.

[0172] This application provides an electrical device, including a battery cell 10 or a battery device 100 provided in any of the above embodiments, wherein the battery cell 10 is used to provide electrical energy to the electrical device.

[0173] Please refer to Figures 4-6. This application embodiment provides a battery cell 10, including a housing 2 and an electrode assembly 1. The electrode assembly 1 is housed within the housing 2 and includes a first electrode 11, a solid electrolyte layer 12, and a second electrode 13 stacked together. The first electrode 11 and the second electrode 13 have opposite polarities. At least a portion of the solid electrolyte layer 12 is disposed between the first electrode 11 and the second electrode 13 along a first direction X. The first electrode 11 includes a first current collector 111 and a first active material layer 112. Along the first direction X, the first active material layer 112 is disposed on the side of the first current collector 111 facing the solid electrolyte layer 12. The electrode assembly 1 also includes a first insulating member 14, which surrounds the outer edge of the first active material layer 112 and connects the first current collector 111 and the solid electrolyte layer 12. The first current collector 111, the first insulating member 14, and the solid electrolyte layer 12 together define a sealed space, within which the first active material layer 112 is housed. The solid electrolyte layer 12 includes an overhang region 121 extending beyond the outer edge of the first active material layer 112 and a main body region 122. The overhang region 121 cooperates with the first current collector 111 to clamp the first insulating member 14. The main body region 122 is stacked with the first active material layer 112, and the main body region has a first surface 1221 facing the first active material layer 112. The overhang region 121 partially protrudes from the first surface 1221.

[0174] A sealed space is defined by the first current collector 111, the first insulating element 14, and the solid electrolyte layer 12. The first active material layer 112 is contained within the sealed space, which restricts the position of the first active material layer 112. During the manufacturing process of the battery cell 10, the first active material layer 112 coated on the first current collector 111 can be pressed to shape the first active material layer 112 and densify the active material of the first active material layer 112, thereby reducing the volume of the first active material layer 112 and improving the conductivity between the active materials. Pressing also makes the connection between the first active material layer 112 and the solid electrolyte layer 12 tighter, which can promote the ion conduction capability between the first active material layer 112 and the solid electrolyte layer 12. By housing the first active material layer 112 within a sealed space, during the pressing process, the first current collector 111 and the solid electrolyte layer 12 are connected by the first insulating member 14. The first insulating member 14 forms a sealed area in both the connection area with the first current collector 111 and the connection area with the solid electrolyte layer 12. The first active material layer 112 is less likely to detach from the sealed area within the sealed space, thereby reducing the risk of the first active material layer 112 detaching from the sealed space and contacting the second electrode 13, which in turn reduces the risk of short circuit within the electrode assembly 1 and improves the reliability of the battery cell 10. By setting the extended region 121 to partially protrude from the first surface 1221, on the one hand, the extended region 121 partially protruding from the first surface 1221 allows the solid electrolyte layer 12 to wrap a portion of the first active material layer 112 in the direction of the first current collector 111, thereby increasing the wrapping effect of the first active material layer 112 on the solid electrolyte layer 12 and improving the restraining effect of the solid electrolyte layer 12 on the first active material layer 112, making the position of the first active material layer 112 more stable; on the other hand, the extended region 121 partially protruding from the first surface 1221 can improve the clamping effect of the extended region 121 and the first current collector 111 on the first insulating member 14, making the position of the first insulating member 14 more stable and improving the structural stability of the electrode assembly 1; furthermore, the extended region 121 protruding from the first surface 1221 in the direction pointing to the first current collector 111 can reduce the size of the first insulating member 14 along the first direction X, thereby saving the material used in the first insulating member 14 and saving the material cost of the first insulating member 14.

[0175] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. 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 single battery cell, comprising: shell; An electrode assembly is housed within a housing. The electrode assembly includes a first electrode, a solid electrolyte layer, and a second electrode stacked together. The first electrode and the second electrode have opposite polarities. At least a portion of the solid electrolyte layer is disposed between the first electrode and the second electrode along a first direction. The first electrode includes a first current collector and a first active material layer. Along the first direction, the first active material layer is disposed on the side of the first current collector facing the solid electrolyte layer. The electrode assembly further includes a first insulating member, which is disposed around the outer edge of the first active material layer and connects the first current collector and the solid electrolyte layer. The first current collector, the first insulating member, and the solid electrolyte layer together define a first accommodating space, in which the first active material layer is accommodated.

2. The battery cell as described in claim 1, wherein, The solid electrolyte layer includes an extended region that extends beyond the outer edge of the first active material layer, and the extended region cooperates with the first current collector to clamp the first insulating member.

3. The battery cell as described in claim 2, wherein, The solid electrolyte layer further includes a main body region, which is stacked with the first active material layer. The main body region has a first surface facing the first active material layer, and the first active material layer is attached to the first surface. The extended region partially protrudes from the first surface along the direction of the solid electrolyte layer toward the first current collector.

4. The battery cell as described in claim 3, wherein, Along the first direction, the thickness of the first active material layer is L1, the thickness of the first insulating element is L2, and 0.5 ≤ L2 / L1 < 1.

5. The battery cell according to any one of claims 2-4, wherein, The first insulating member has a second surface facing away from the first current collector, and the extended area covers the second surface; and / or, the first insulating member has a third surface facing the first current collector, and the first current collector covers the third surface.

6. The battery cell according to any one of claims 2-5, wherein, In a projection plane perpendicular to the first direction, the projection of the extended area overlaps with the projection of the first insulating element, and the width of the overlapping area is 1mm-5mm.

7. The battery cell according to any one of claims 1-6, wherein, The solid electrolyte layer has a first surface facing the first active material layer, the first active material layer being attached to the first surface, and a portion of the first insulating member protruding from the first surface in the direction of the first current collector toward the solid electrolyte layer.

8. The battery cell as described in claim 7, wherein, Along the first direction, the thickness of the first active material layer is L1, the thickness of the first insulating element is L2, and 1 < L2 / L1 ≤ 2.

9. The battery cell according to any one of claims 1-8, wherein, Along the first direction, the thickness of the first active material layer is L1, the thickness of the first insulating element is L2, and 0.5≤L2 / L1≤2.

10. The battery cell according to any one of claims 1-9, wherein, The first insulating element has a ring structure and a wall thickness of 1mm-5mm.

11. The battery cell according to any one of claims 1-10, wherein, Along the first direction, the thickness of the solid electrolyte layer is 10μm-50μm.

12. The battery cell according to any one of claims 1-11, wherein, The second electrode includes a second current collector and a second active material layer. Along the first direction, the second active material layer is disposed on the side of the second current collector facing the solid electrolyte layer.

13. The battery cell as described in claim 12, wherein, The first electrode is the negative electrode, and the second electrode is the positive electrode; In a projection plane perpendicular to the first direction, the projection of the second active material layer lies within the projection of the first active material layer, and the projected area of ​​the second active material layer is smaller than the projected area of ​​the first active material layer.

14. The battery cell as described in claim 13, wherein, In a projection plane perpendicular to the first direction, the minimum distance between the projection of the outer edge of the second active material layer and the projection of the outer edge of the first active material layer is 0mm-5mm.

15. The battery cell according to any one of claims 12-14, wherein, The electrode assembly further includes a second insulating member, which is disposed around the outer edge of the second active material layer and connects the second current collector and the solid electrolyte layer. The second current collector, the second insulating member, and the solid electrolyte layer together define a second accommodating space, in which the second active material layer is accommodated.

16. The battery cell as described in claim 15, wherein, The second insulating element is a ring structure, and the second accommodating space is a closed space.

17. The battery cell according to any one of claims 1-16, wherein, The first insulating element is a ring structure, and the first accommodating space is a closed space.

18. A battery device comprising a battery cell as described in any one of claims 1-17.

19. An electrical device comprising a battery cell as described in any one of claims 1-17 or a battery device as described in claim 18, wherein the battery cell is used to provide electrical energy to the electrical device.

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