Battery cell, battery device, and electric device

Abstract

This application relates to the field of battery technology, providing a battery cell, a battery device, and an electrical device. The battery cell includes a housing, an electrode assembly, and an insulating component. The electrode assembly is disposed on the housing, with the electrode posts protruding from the end face of the housing. The insulating component covers the outside of the housing, with the electrode posts exposed within the insulating component. The insulating component includes multiple substrate layers, with the thickness of the first substrate layer being greater than the thickness of the other substrate layers, and the first substrate layer being adjacent to the housing. By increasing the thickness of the first substrate layer, the total thickness of the insulating component can be increased, improving the insulation withstand voltage performance of the battery cell to meet the insulation withstand voltage requirements of the high-voltage system of the electrical device. Furthermore, increasing the thickness of the substrate layers near the housing can improve the impact and puncture resistance of the insulating component, enhancing its protection of the housing and electrode assembly, extending the service life of the insulating component, and thus improving the safety and reliability of the battery cell.

Description

Technical Field

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

[0002] In related technologies, battery cells are insulated and protected by external insulating components. High-voltage systems in electrical installations place higher demands on the insulation withstand voltage performance of battery cells. Utility Model Content

[0003] In view of this, embodiments of this application provide a battery cell that can improve the insulation withstand voltage performance of the battery cell.

[0004] The technical solution of this application embodiment is implemented as follows:

[0005] This application provides a single battery cell, including:

[0006] case;

[0007] An electrode assembly is disposed in the housing, wherein the electrode post of the electrode assembly protrudes from the end face of the housing;

[0008] An insulating component is provided to cover the exterior of the housing, with the pole exposed outside the insulating component;

[0009] The insulating component includes multiple substrate layers, the thickness of the first substrate layer is greater than the thickness of the other substrate layers, and the first substrate layer is adjacent to the housing.

[0010] In this embodiment, the first substrate layer refers to the substrate layer closest to the casing. Among all substrate layers, the first substrate layer has the greatest thickness, exceeding the thickness of each of the other substrate layers. The substrate layer can be a polyester substrate layer, a polyimide substrate layer, or a polypropylene substrate layer, etc., for example, a PET substrate layer. By increasing the thickness of the first substrate layer, the total thickness of the insulating component can be increased, improving the insulation withstand voltage performance of the battery cell to meet the insulation withstand voltage requirements of the high-voltage system of the electrical device. Furthermore, increasing the thickness of the substrate layer closest to the casing can improve the impact and puncture resistance of the insulating component. For example, when the casing is made of metal, there may be sharp objects such as metal burrs on the surface. By increasing the thickness of the first substrate layer, the possibility of the insulating component being punctured can be reduced, enhancing the protection of the casing and electrode components, reducing the risk of insulation failure due to chemical corrosion, extending the service life of the insulating component, and thus improving the safety and reliability of the battery cell.

[0011] In some embodiments, the thickness of the insulating element is 160~300μm.

[0012] In this embodiment, increasing the thickness of the insulating component to 160 μm or greater can improve the insulation withstand voltage performance of the battery cell, thereby meeting the insulation withstand voltage requirements of the high-voltage system of the electrical device. Limiting the thickness of the insulating component to the range of 160~300 μm can reduce the possibility that an excessively thick insulating component would occupy too much space and be detrimental to improving the energy density of the battery cell, and reduce the possibility that an excessively thin insulating component would result in insufficient insulation withstand voltage performance.

[0013] In some embodiments, the thickness of the insulating element is 175~200μm.

[0014] In this way, the dual requirements of limiting the thickness of the insulation component and improving the insulation withstand voltage performance of the insulation component can be better met.

[0015] In some embodiments, the insulating element is overlapped along the side of the housing.

[0016] The insulating component covers the outside of the shell, with more than one but less than two wraps, and the insulating components are overlapped to form an overlapping area.

[0017] In some embodiments, the overlap distance of the insulating element along the side of the housing is greater than or equal to 28 mm.

[0018] In this way, the design requirements for the creepage distance of individual battery cells in the high-voltage system of the electrical device can be met, as well as the insulation withstand voltage requirements.

[0019] In some embodiments, the overlap distance is greater than or equal to 30 mm.

[0020] In some embodiments, the insulating element further includes an adhesive layer, which is overlapped and compounded with the substrate layer. The first adhesive layer is connected to the housing, and the number of both the adhesive layer and the substrate layer is 2 to 5.

[0021] The first adhesive layer refers to the adhesive layer that connects to the shell. This adhesive layer can be a polypropylene adhesive layer, an acrylic adhesive layer, etc. Adjacent substrate layers are fixedly connected by the adhesive layer between them.

[0022] In some embodiments, the substrate layer between two adjacent adhesive layers has a plurality of pores extending through the substrate layer along the thickness direction, and the two adjacent adhesive layers are connected through the pores.

[0023] After the insulating component is formed, the pores are filled with the adhesive of the bonding layer. Adjacent bonding layers can be connected through the pores, which enhances the bonding performance between the bonding layers and strengthens the protective effect of the insulating component on the electrode assembly. At the contact interface between the bonding layer and the substrate layer, the adhesive of the bonding layer is embedded in the pore structure to form an interlocking structure, thereby creating a mechanical interlocking effect between the substrate layer and the bonding layer, improving the bonding performance between them, thus improving the stability between film layers, and further improving the problems of interlayer slippage and delamination of the insulating component.

[0024] In some embodiments, the insulating element is folded along the end face of the housing, and the folding distance is greater than or equal to 12 mm.

[0025] In this way, increasing the folding distance of the insulating component to greater than or equal to 12mm can adjust the ratio of the folding distance to the thickness of the insulating component, increase the bonding length of the folding, reduce the possibility of the folding lifting, and at the same time increase the creepage distance, thereby improving safety performance.

[0026] In some embodiments, the insulating element is provided to fully cover one end face of the housing and is provided with a folded edge along the other end face of the housing, and the pole protrudes from the end face of the housing where the folded edge of the insulating element is located.

[0027] In some embodiments, the end face region of the housing corresponding to the folded edge of the insulating element is configured as a laser-textured surface.

[0028] Laser roughening refers to the process of increasing the roughness of the end face area by irradiating the edge with a high-energy-density laser beam.

[0029] In some embodiments, the end face region of the housing corresponding to the folded edge of the insulating member is configured as a sandblasted surface.

[0030] A sandblasted surface refers to a surface treated by using high-speed jets of hard abrasive particles to impact the end face area where the edge is folded, thereby increasing the roughness of the end face.

[0031] In some embodiments, the end face region of the housing corresponding to the folded edge of the insulating element is configured as a mechanically polished surface.

[0032] Mechanically polished surfaces refer to roughened surfaces created by mechanical friction between an abrasive tool and the end face area containing the folded edge, removing some of the surface material and forming a microscopic texture. Abrasive tools can include sandpaper, grinding wheels, grinding heads, wire drawing wheels, etc.

[0033] This application also provides a battery device, including any of the battery cells described in any of the embodiments of this application.

[0034] In some embodiments, the battery device further includes:

[0035] Metal straps are attached to the sides of the multiple battery cells to bind the multiple battery cells together as a whole.

[0036] The metal strap is wrapped around and in contact with the insulating component. The metal strap is conductive, and the creepage distance to the side of the housing must be considered to meet design requirements.

[0037] This application embodiment also provides an electrical device, including:

[0038] The battery device described in this application embodiment is used to store or provide electrical energy.

[0039] Electrical devices can include mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft, such as airplanes, rockets, space shuttles, and spacecraft.

[0040] The embodiments of this application have the following beneficial effects:

[0041] The battery cell, battery device, and power-consuming device provided in this application increase the total thickness of the insulating components by increasing the thickness of the first substrate layer, thereby improving the insulation withstand voltage performance of the battery cell and meeting the insulation withstand voltage requirements of the high-voltage system of the power-consuming device. Furthermore, increasing the thickness of the substrate layer near the casing improves the impact and puncture resistance of the insulating components. For example, when the casing is made of metal, sharp objects such as metal burrs may exist on the surface. Increasing the thickness of the first substrate layer reduces the possibility of the insulating components being punctured, enhances the protection of the casing and electrode components, reduces the risk of insulation failure due to chemical corrosion, extends the service life of the insulating components, and thus improves the safety and reliability of the battery cell. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of an electrical device according to an embodiment of this application;

[0043] Figure 2 This is a schematic diagram of the structure of a battery device according to an embodiment of this application;

[0044] Figure 3 This is a partial structural diagram of a battery cell in one embodiment of this application;

[0045] Figure 4 This is a top view of a battery cell in one embodiment of this application;

[0046] Figure 5 This is a partial schematic diagram of a portion of the structure of a battery device in one embodiment of this application.

[0047] Explanation of reference numerals in the attached figures

[0048] 100. Battery cell; 10. Housing; 11. End face; 12. Side; 20. Electrode assembly; 21. Terminal post; 30. Insulator; 31. Overlap area; 40. Pressure relief valve; 1000. Electrical device; 200. Battery assembly; 210. Battery box; 211. Box body; 212. Cover; 300. Controller; 400. Motor; 201. Metal strap; X, First direction; Y, Second direction; Z, Third direction. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. The described embodiments should not be regarded as limitations on this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0050] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this application, but should not be used to limit the scope of this application.

[0051] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0052] In the description of this specification, references to terms such as "some embodiments" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the embodiments of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine the different embodiments or examples described in this application, as well as the features of those different embodiments or examples.

[0053] In related technologies, battery cells are insulated and protected by external insulating components. High-voltage systems in electrical devices place higher demands on the insulation withstand voltage performance of battery cells. In this application's embodiments, a high-voltage system refers to an electrical device whose entire energy storage power station or battery device outputs a maximum AC voltage of 35kV or higher, or a DC voltage of ±100kV or higher. For example, according to the Chinese national standard GB / T156-2017 "Standard Voltages," the battery cells in this application's embodiments can be applied to high-voltage systems, ultra-high-voltage systems, or extra-high-voltage systems.

[0054] In view of this, embodiments of this application provide a battery cell that can improve the insulation withstand voltage performance of the battery cell.

[0055] This application also provides a battery device, which includes a single battery cell according to any one of the embodiments of this application.

[0056] In some embodiments, the battery device also includes straps that surround the sides of the plurality of battery cells to bind the plurality of battery cells together as a whole.

[0057] This application also provides an electrical device, which includes a battery device according to any one of the embodiments of this application, for storing or providing electrical energy.

[0058] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use individual battery cells, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft.

[0059] Please refer to Figure 1 This application will describe an example of an electrical device 1000, exemplified by a vehicle. The vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 200 is installed inside the vehicle, and the battery device 200 can be located at the bottom, front, or rear of the vehicle. The battery device 200 can be used to power the vehicle; for example, it can serve as the vehicle's operating power source. The vehicle may also include a controller 300 and a motor 400. The controller 300 controls the battery device 200 to supply power to the motor 400, for example, to meet the vehicle's power needs during starting, navigation, and driving.

[0060] Please refer to Figure 2The battery device 200 includes a battery case 210 and battery cells 100, with the battery cells 100 housed within the battery case 210. The battery case 210 provides space for the battery cells 100 and can have various structures. For example, the battery case 210 includes a case body 211 and a cover 212, with the cover 212 covering the case body 211 to form a housing space, within which the battery cells 100 are disposed.

[0061] In the battery device 200, there can be multiple battery cells 100, which can be connected in series, parallel, or in a mixed manner. A mixed connection means that multiple battery cells 100 are connected in both series and parallel configurations. Multiple battery cells 100 can be directly connected in series, parallel, or in a mixed manner, and then the entire assembly of the multiple battery cells 100 is housed within the battery box 210. Alternatively, the battery device 200 can also consist of multiple battery cells 100 first connected in series, parallel, or in a mixed manner to form battery modules, and then these battery modules are connected in series, parallel, or in a mixed manner to form a whole, which is also housed within the battery box 210. The battery device 200 may also include other structures; for example, it may include a busbar component for electrical connection between the multiple battery cells 100.

[0062] In some embodiments, the battery device 200 includes a battery management system, which is a core component responsible for monitoring and managing the status of individual battery cells 100. Its main functions include: real-time monitoring of parameters such as voltage, current, and temperature of individual battery cells 100 to ensure that the battery is in a safe working state; balancing the charge of each individual battery cell 100 in the battery cell group 100 through active or passive means to extend the battery life; controlling and regulating the temperature of individual battery cells 100 to avoid performance degradation or safety risks caused by overheating or overcooling; detecting faults in the battery cell group 100 and the BMS itself, and taking corresponding protective measures, such as cutting off power and alarming.

[0063] As an example, the battery management system can be housed in the enclosure 211 to support and protect the battery management system.

[0064] As an example, the battery management system can also be located outside the housing 211 and connected to the battery cells 100, sensors and other devices inside the housing 211 via wires.

[0065] 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.

[0066] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc. The embodiments of this application take lithium-ion batteries as an example for illustration.

[0067] Please see Figure 3 The battery cell 100 includes an electrode assembly 20. The electrode assembly 20 includes a positive electrode, a negative electrode, and a separator. The positive electrode can be a positive electrode sheet, the negative electrode can be a negative electrode sheet, and the separator is disposed between the negative and positive electrodes. During the charging and discharging process of the battery cell 100, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, disposed between the positive and negative electrodes, serves to prevent short circuits between the positive and negative electrodes while allowing active ions to pass through.

[0068] In some embodiments, the positive electrode sheet may include a positive current collector and a positive active material disposed on at least one surface of the positive current collector.

[0069] 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.

[0070] As an example, the positive current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0071] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxides include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3O2 (Also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1O2 (Also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.8 Co 0.15 Al 0.05 At least one of O2 and its modified compounds. Modified compounds refer to substances obtained by modification methods such as doping or coating based on the above-mentioned substances.

[0072] In some embodiments, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0073] As an example, the negative electrode current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. The composite current collector may include a polymer material substrate and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0074] 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.

[0075] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cell 100. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials for battery cell 100 may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0076] As an example, negative electrode active materials can be filled or / and deposited within the negative electrode current collector.

[0077] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0078] In some embodiments, the separator is a separator membrane. This application does not impose any particular limitation on the type of separator membrane; any known porous separator membrane with good chemical and mechanical stability can be selected.

[0079] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separator can be a single component located between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes. An inorganic particle coating, an organic particle coating, or an organic / inorganic composite coating can also be applied to the surface of the separator.

[0080] 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.

[0081] In some embodiments, the electrode assembly 20 is a wound structure. The positive electrode and the negative electrode are wound into a wound structure.

[0082] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0083] As an example, multiple positive electrode plates can be provided, and negative electrode plates can be folded to form multiple stacked folded segments, with a positive electrode plate sandwiched between adjacent folded segments.

[0084] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0085] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0086] As an example, the separators can be continuously arranged, either by folding or rolling between any adjacent positive or negative electrode plates.

[0087] In some embodiments, the electrode assembly 20 can be cylindrical, flat, or polygonal. This application uses a flat cylindrical electrode assembly 20 as an example for illustration.

[0088] In some embodiments, the electrode assembly 20 is provided with tabs that can conduct current from the electrode assembly 20. The tabs include a positive tab and a negative tab.

[0089] In some implementations, please refer to Figure 2 The battery cell 100 may include a housing 10. The housing 10 may be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film, etc. In some embodiments, the housing 10 may be a sealed structure or a non-sealed structure. As an example, when the housing 10 is a non-sealed structure, the housing 10 serves to protect the electrode assembly 20, and a sealing bag is also included between the housing 10 and the electrode assembly 20. The sealing bag is used to encapsulate the electrode assembly 20 and the electrolyte. Specifically, the sealing bag may be a bag-shaped insulating component or an aluminum-plastic film. When the housing 10 is a sealed structure, it is used to encapsulate the electrode assembly 20 and the electrolyte, etc.

[0090] In some embodiments, the housing 10 includes an end cap and a housing body, the housing body having an opening, and the end cap covering the opening. The housing body may have one or more openings. The end cap may also be provided one or more.

[0091] The following, in conjunction with the appendix Figures 2 to 5The present application provides a detailed description of the battery cell through specific embodiments.

[0092] In some embodiments, please refer to Figure 3 and Figure 4 The battery cell 100 includes a housing 10, an electrode assembly 20, and an insulating member 30. The electrode assembly 20 is disposed on the housing 10, and the electrode post 21 of the electrode assembly 20 protrudes from the end face 11 of the housing 10. The insulating member 30 covers the outside of the housing 10, and the electrode post 21 is exposed in the insulating member 30. The insulating member 30 includes multiple substrate layers, the thickness of the first substrate layer is greater than the thickness of the other substrate layers, and the first substrate layer is adjacent to the housing 10. As an example, the substrate layers can be polyester substrate layers, polyimide substrate layers, or polypropylene substrate layers, etc. For example, the substrate layers can be PET substrate layers.

[0093] The first substrate layer refers to the substrate layer closest to the shell 10. Among all the substrate layers, the first substrate layer has the greatest thickness, which is greater than the thickness of each of the other substrate layers.

[0094] In some embodiments, the insulating element 30 further includes an adhesive layer, which is overlapped and laminated with the substrate layer. As an example, the adhesive layer may be a polypropylene adhesive layer or an acrylic adhesive layer, etc.

[0095] In this way, two adjacent substrate layers are fixedly connected by an adhesive layer between them.

[0096] In other embodiments, adjacent substrate layers are directly connected by hot pressing. That is, no adhesive layer is provided between adjacent substrate layers.

[0097] In some embodiments, the first adhesive layer is connected to the housing 10. The first adhesive layer refers to the adhesive layer connected to the housing 10.

[0098] Thus, the first substrate layer is connected to the housing 10 through the first adhesive layer.

[0099] In other embodiments, the first substrate layer is connected to the housing 10 by an adhesive, such as a structural adhesive.

[0100] The battery cell 100 provided in this application embodiment increases the total thickness of the insulating component 30 by increasing the thickness of the first substrate layer, thereby improving the insulation withstand voltage performance of the battery cell 100 to meet the insulation withstand voltage requirements of the high-voltage system of the electrical device. Furthermore, increasing the thickness of the substrate layer near the housing 10 improves the impact and puncture resistance of the insulating component 30. For example, when the housing 10 is made of metal, there may be sharp objects such as metal burrs on the surface. By increasing the thickness of the first substrate layer, the possibility of the insulating component 30 being punctured can be reduced, enhancing the protection of the housing 10 and the electrode assembly 20, reducing the risk of insulation failure due to chemical corrosion of the insulating component 30, extending the service life of the insulating component 30, and thus improving the safety and reliability of the battery cell 100.

[0101] Furthermore, the number of adhesive layers is 2 to 5.

[0102] Furthermore, the number of substrate layers is 2 to 5.

[0103] Furthermore, the number of adhesive layers and substrate layers is 2 to 5.

[0104] In some embodiments, the thickness of the insulating element 30 can be increased by increasing the number of adhesive layers and substrate layers.

[0105] In some embodiments, the substrate layer between two adjacent adhesive layers has multiple pores penetrating the substrate layer along the thickness direction, and the two adjacent adhesive layers are connected through the pores.

[0106] After the insulating component 30 is formed, the pores are filled with the adhesive of the bonding layer. Adjacent bonding layers can be connected through the pores, which can enhance the bonding performance between the bonding layers and strengthen the protective effect of the insulating component 30 on the electrode assembly 20. At the contact interface between the bonding layer and the substrate layer, the adhesive of the bonding layer is embedded in the pore structure to form an interlocking structure, thereby creating a mechanical interlocking effect between the substrate layer and the bonding layer, improving the bonding performance between them, thereby improving the interlayer stability and further improving the interlayer slippage and detachment problems of the insulating component 30.

[0107] In some embodiments, the thickness of the insulating element 30 is 160~300μm (micrometers), for example, it can be 160μm, 170μm, 175μm, 180μm, 185μm, 190μm, 200μm, 210μm, 220μm, 230μm, 240μm, 250μm, 260μm, 270μm, 280μm, 290μm, 300μm, etc.

[0108] In this embodiment, increasing the thickness of the insulating component 30 to 160 μm or greater improves the insulation withstand voltage performance of the battery cell 100, thereby meeting the insulation withstand voltage requirements of the high-voltage system of the electrical device. Limiting the thickness of the insulating component 30 to the range of 160-300 μm reduces the possibility that an excessively thick insulating component 30 would occupy too much space and hinder the improvement of the battery cell's energy density, and also reduces the possibility that an excessively thin insulating component 30 would result in insufficient insulation withstand voltage performance. For example, increasing the thickness of the insulating component 30 to 180 μm or greater, such as 185 μm, can meet the 9300V insulation withstand voltage requirement of the battery cell.

[0109] Furthermore, the thickness of the insulating element 30 is 175~200μm, for example, it can be 175μm, 180μm, 185μm, 190μm or 200μm, etc. In this way, the dual requirements of limiting the thickness of the insulating element 30 to be too large and improving the insulation withstand voltage performance of the insulating element 30 can be better met.

[0110] In some embodiments, the thickness of the first substrate layer is greater than or equal to 100 μm, for example, it can be 100 μm, 110 μm, 120 μm, 130 μm, 150 μm, 180 μm, or 200 μm, etc.

[0111] The housing 10 has multiple housing walls, which enclose a cavity in which the electrode assembly 20 is disposed. Each housing wall has an end face 11 and a side face 12. The end face 11 refers to the surface of the housing wall where the electrode post 21 or the pressure relief valve 40 is disposed; for example, two housing walls may be arranged opposite each other to form two end faces 11.

[0112] Side walls 12 are formed in multiple shell walls, and side walls 12 refer to the peripheral shell walls of the battery cell 100.

[0113] For some implementation methods, please refer to Figures 2 to 4 The battery cell 100 has six shell walls. Two of the shell walls are arranged opposite each other along a first direction X to form two side surfaces 12, which are called the first side surfaces. Two other shell walls are arranged opposite each other along a second direction Y to form two other side surfaces 12, which are called the second side surfaces. Two shell walls are arranged opposite each other along a third direction Z to form two end faces 11 of the battery cell 100. The first direction X, the second direction Y, and the third direction Z are all perpendicular to each other, and the third direction Z is in the same direction as the height of the battery cell 100. The larger of the first and second side surfaces can also be referred to as the larger surface.

[0114] In some embodiments, the battery cell 100 is a prismatic battery cell, with a shape approximately similar to a cuboid. This regular shape of the battery cell 100 improves space utilization, increases the energy density of the battery device 200, and facilitates the arrangement of multiple battery cells 100 along the first direction X and also along the second direction Y.

[0115] In some embodiments, please refer to Figure 4 The battery cell 100 includes two terminals 21. For example, the two terminals 21 are disposed on the same end face 11 on the same side of the battery cell 100.

[0116] For example, please refer to Figure 3 and Figure 4 The battery cell 100 includes a pressure relief valve 40, which is used to release pressure when the battery cell 100 malfunctions. The pressure relief valve 40 can be designed in various forms according to requirements, such as an explosion relief valve or an explosion relief plate.

[0117] For example, please refer to Figure 3 The terminal post 21 and the pressure relief valve 40 are located on the same end face 11 of the battery cell 100.

[0118] In other embodiments not shown, the terminal post 21 and the pressure relief valve 40 are respectively disposed on the end faces 11 of opposite sides of the battery cell 100. Alternatively, the two terminal posts 21 are respectively disposed on the end faces 11 of opposite sides of the battery cell 100.

[0119] The insulating component 30 covers the exterior of the housing 10, providing electrical insulation and protection, reducing the possibility of short circuits in the battery cells 100, protecting the structure of the housing 10 and the internal electrode assembly 20, and reducing the possibility of structural damage during manufacturing, transportation, and use. In some embodiments, the insulating component 30 is a blue film. The blue film has excellent mechanical strength, insulation, and high-temperature resistance, providing electrical insulation and protection, while the blue color facilitates visual management during production.

[0120] In some embodiments, please refer to Figure 5 The insulating element 30 is overlapped along the side 12 of the housing 10. The insulating element 30 covers the outside of the housing 10, with more than one but less than two wraps, and the overlapping of the insulating element 30 forms an overlapping area 31.

[0121] The battery cell 100 must meet the creepage distance requirement. Creepage distance refers to the shortest path between two conductive parts measured along the insulating surface. Insufficient creepage distance may lead to the formation of a conductive path on the insulating surface, thereby causing a malfunction. Therefore, the battery cell 100 must meet the creepage distance design requirements to reduce the possibility of insulation breakdown or creepage under high voltage.

[0122] In some embodiments, the straps are positioned around the sides of multiple battery cells 100, surrounding and contacting the insulating member 30. Further, the straps are configured as metal straps 201, which are conductive. The creepage distance from the metal straps 201 to the side surface 12 of the housing 10 must be considered to meet design requirements.

[0123] To meet creepage distance requirements, please refer to some embodiments. Figure 5 The overlap distance S0 of the insulating component 30 along the side 12 is greater than or equal to 28 mm, for example, it can be 28 mm, 29 mm, 30 mm, 33 mm, 35 mm, 40 mm or 50 mm, etc., to meet the design requirements of the high-voltage system of the electrical device for the creepage distance of the battery cell 100 and to meet the insulation withstand voltage requirements. For example, an overlap distance S0 greater than or equal to 28 mm can meet the insulation withstand voltage requirement of 9300V for the battery cell. In some embodiments, the overlap distance S0 is greater than or equal to 30 mm, for example, it can be 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 80 mm, 90 mm or 100 mm, etc.

[0124] In some embodiments, please refer to Figure 4 The insulating element 30 is provided along the folded edge of the end face 11 of the housing 10, and the pole post 21 protrudes from the end face 11 of the housing 10 where the folded edge of the insulating element 30 is located.

[0125] As an optional implementation, the insulating member 30 is provided to fully cover one end face 11 of the housing 10 and is provided with a folded edge along the other end face 11 of the housing 10, and the pole post 21 protrudes from the end face 11 of the housing 10 where the folded edge of the insulating member 30 is located.

[0126] Considering that thickening the insulation element 30 may cause the folded edge to warp, please refer to some embodiments. Figure 4 The folding distance S1 is greater than or equal to 12mm. Thus, by increasing the folding distance S1 of the insulating component 30 to greater than or equal to 12mm, the ratio of the folding distance S1 to the thickness of the insulating component 30 can be adjusted, increasing the bonding length of the fold, reducing the possibility of the fold lifting, and increasing the creepage distance, thereby improving safety performance.

[0127] In some embodiments, in order to reduce the possibility of edge warping, the end face 11 of the housing 10 can be pre-treated to increase the roughness of the end face 11, increase the bonding strength between the adhesive layer and the surface of the housing 10, increase the effective contact area between the adhesive layer and the housing 10, and make the adhesive layer and the housing 10 mechanically fit together after the adhesive layer is cured.

[0128] As an optional implementation, the end face region of the housing 10 where the folded edge of the insulating member 30 is located is configured as a laser-textured surface. A laser-textured surface refers to a processed surface formed by increasing the roughness of the end face 11 by irradiating the end face region where the folded edge is located with a high-energy-density laser beam.

[0129] In other embodiments, the end face region of the housing 10 where the folded edge of the insulating member 30 is located is configured as a sandblasted surface. A sandblasted surface refers to a surface treated by impacting the end face region where the folded edge is located with high-speed jets of hard abrasive particles, thereby increasing the roughness of the end face 11.

[0130] In other embodiments, the end face region of the housing 10 where the folded edge of the insulating member 30 is located is configured as a mechanically polished surface. A mechanically polished surface refers to a roughened surface formed by mechanical friction between an abrasive tool and the end face region where the folded edge is located, removing some of the surface material and creating a microscopic texture. The abrasive tool can be sandpaper, a grinding wheel, a grinding head, a wire drawing wheel, etc.

[0131] As an optional implementation, the housing 10 is an aluminum shell, and the original oxide layer, oil stains and impurities on the surface of the aluminum shell are removed by physical friction to form a roughened surface.

[0132] In some embodiments, the battery cell 100 includes a housing 10, an electrode assembly 20, and an insulating member 30. The insulating member 30 includes an overlapping adhesive layer and a substrate layer, each consisting of three layers. Adjacent substrate layers are fixedly connected by an adhesive layer between them, with the thickness of the first substrate layer being greater than the thickness of the other substrate layers. The adhesive layer is a polyacrylic adhesive layer, and the substrate layer is a PET substrate layer. Metal straps 201 are attached to the sides of the multiple battery cells 100 and contact the insulating member 30 to bundle the multiple battery cells 100 together. The electrode assembly 20 is disposed on the housing 10, with the electrode post 21 of the electrode assembly 20 protruding from the end face 11 of the housing 10. The insulating member 30 covers the outside of the housing 10, with the electrode post 21 exposed outside the insulating member 30, which has a thickness of 185 μm. The insulating member 30 overlaps along the side 12 of the housing 10, with an overlap distance S0 of 30 mm. The insulating element 30 is fully covered along one end face 11 of the housing 10 and is folded along the other end face 11 of the housing 10 with a folding distance S1 of 12 mm. The pole post 21 protrudes from the end face 11 of the housing 10 where the folding edge of the insulating element 30 is located. The end face area of ​​the housing 10 where the folding edge of the insulating element 30 is located is configured as a laser-textured surface.

[0133] In this embodiment, by increasing the thickness of the first substrate layer to 185 μm, the insulation withstand voltage performance of the battery cell 100 can be improved, meeting the 9300V insulation withstand voltage requirement of the battery cell. Furthermore, increasing the thickness of the substrate layer near the housing 10 improves the impact and puncture resistance of the insulation component 30. For example, when the housing 10 is made of metal, there may be sharp objects such as metal burrs on the surface. Increasing the thickness of the first substrate layer reduces the possibility of the insulation component 30 being punctured, enhancing the protection of the housing 10 and the electrode assembly 20, reducing the risk of insulation failure due to chemical corrosion, extending the service life of the insulation component 30, and thus improving the safety and reliability of the battery cell 100. The overlap distance S0 is 30 mm, which meets the design requirements of the high-voltage system for the creepage distance of the battery cell 100 and satisfies the insulation withstand voltage requirements. Increasing the folding distance S1 of the insulating component 30 to greater than or equal to 12mm allows adjustment of the ratio of the folding distance S1 to the thickness of the insulating component 30, increasing the bonding length of the fold, reducing the possibility of fold lifting, and simultaneously increasing the creepage distance, thus improving safety performance. Laser roughening refers to the treatment surface formed by irradiating the end face area where the fold is located with a high-energy-density laser beam, increasing the roughness of the end face 11.

[0134] The above description is merely a preferred embodiment of this application and is not intended to limit the application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A battery cell, characterized by, include: case; An electrode assembly is disposed in the housing, wherein the electrode post of the electrode assembly protrudes from the end face of the housing; An insulating component is provided to cover the exterior of the housing, with the pole exposed outside the insulating component; The insulating component includes multiple substrate layers, the thickness of the first substrate layer is greater than the thickness of the other substrate layers, and the first substrate layer is adjacent to the housing.

2. The battery cell according to claim 1, characterized in that, The thickness of the insulating component is 160~300μm.

3. The battery cell according to claim 2, characterized in that, The thickness of the insulating component is 175~200μm.

4. The battery cell according to claim 1, characterized in that, The insulating element is overlapped along the side of the housing.

5. The battery cell according to claim 4, characterized in that, The overlap distance of the insulating component along the side of the housing is greater than or equal to 28 mm.

6. The battery cell according to claim 5, characterized in that, The overlap distance is greater than or equal to 30mm.

7. The battery cell according to claim 1, characterized in that, The insulating component further includes an adhesive layer, which is overlapped and composited with the substrate layer. The first adhesive layer is connected to the housing, and the number of both the adhesive layer and the substrate layer is 2 to 5.

8. The battery cell according to claim 7, characterized in that, Each of the substrate layers between two adjacent adhesive layers has a plurality of pores extending through the substrate layer along the thickness direction, and the two adjacent adhesive layers are connected through the pores.

9. The battery cell according to claim 1, characterized in that, The insulating component is folded along the end face of the housing, and the folding distance is greater than or equal to 12mm.

10. The battery cell according to claim 9, characterized in that, The insulating component is fully covered along one end face of the housing and folded along the other end face of the housing. The pole protrudes from the end face of the housing where the folded edge of the insulating component is located.

11. The battery cell according to claim 9, characterized in that, The end face area of ​​the housing corresponding to the folded edge of the insulating component is configured as a laser-textured surface, a sandblasted surface, or a mechanically polished surface.

12. A battery device, characterized in that, Includes the battery cell as described in any one of claims 1 to 11.

13. The battery device according to claim 12, characterized in that, The battery device also includes: Metal straps are attached to the sides of the multiple battery cells to bind the multiple battery cells together as a whole.

14. An electrical appliance, characterized in that, include: The battery device of claim 12 or 13 is used to store or provide electrical energy.

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