Battery cells and devices, electric devices, energy storage devices and systems, charging networks

Abstract

The application provides a battery monomer and device, an electric device, an energy storage device and system, and a charging network, and belongs to the technical field of batteries. The battery monomer comprises an electrode assembly, a shell, and a bottom support plate. The shell is formed with an accommodating cavity for accommodating the electrode assembly. The bottom support plate is located between the electrode assembly and the inner wall of the shell and is used for supporting the electrode assembly. The bottom support plate comprises a support piece, the support piece comprises a metal layer, and an insulating coating layer covers the outer surface of the metal layer. The application can improve the reliability of the structure of the battery monomer.

Description

Technical Field

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

[0002] Energy conservation and emission reduction are key to sustainable social development. Rechargeable batteries, with their ability to store and release energy as needed, are widely used in various electrical devices and energy storage systems, and are an important component in promoting energy transition and sustainable development. For the new energy industry, battery technology is a crucial factor in its development.

[0003] The bottom of the battery casing is usually equipped with a base plate to support the electrode assembly. When a battery cell experiences thermal runaway, the base plate will melt due to the high temperature, causing the base plate support structure to fail and unable to support the electrode assembly, thereby affecting the reliability of the battery cell structure. Utility Model Content

[0004] This application aims to at least address one of the technical problems existing in the background art. Therefore, one objective of this application is to provide a battery cell and device, an electrical device, an energy storage device and system, and a charging network to improve the reliability of the battery cell structure.

[0005] An embodiment of the first aspect of this application provides a battery cell, the battery cell including an electrode assembly, a housing and a base plate, the housing forming a receiving cavity for accommodating the electrode assembly; the base plate is located between the electrode assembly and the inner wall of the housing and is used to support the electrode assembly; wherein the base plate includes a support member, the support member including a metal layer and an insulating coating covering the outer surface of the metal layer.

[0006] In the technical solution of this application embodiment, by covering the outer surface of the metal layer with an insulating coating, the metal layer can be isolated and insulated from the electrode assembly and the housing, which helps to prevent the metal layer and the housing from undergoing electrochemical corrosion under the action of the electrolyte. At the same time, the metal layer has better mechanical properties, which can better support the electrode assembly and improve the reliability of the battery cell structure.

[0007] In some embodiments, the base plate further includes a first insulating member and a second insulating member. The first insulating member is located on the surface of the support member facing the electrode assembly, and the second insulating member is located on the surface of the support member facing away from the electrode assembly. The first and second insulating members are connected along the outer periphery of the support member to completely enclose the support member between them. By completely enclosing the support member within the insulating members, the support member is separated from the electrode assembly and the housing, particularly from the electrolyte, further improving the isolation effect between the metal layer and the electrolyte in the support member. The first and second insulating members, sleeved on the outer surface of the support member, serve as a first layer of insulation between the base plate and the housing, and a first layer of isolation from the electrolyte. The insulating coating can then serve as a second layer of insulation and a second layer of isolation should the first layer of insulation fail, improving the reliability of the base plate support. Furthermore, since the support member containing the metal layer has high hardness, the external first and second insulating members can alleviate friction between the base plate and the interior of the housing, reducing the risk of debris generation and insulation failure due to cracking of the insulating coating on the surface of the metal layer.

[0008] In some embodiments, the support member has at least one first groove extending through the support member along its thickness direction, and the first insulating member and the second insulating member are connected at the location of the first groove to form a first connecting portion. By creating the first groove on the support member and connecting the first insulating member and the second insulating member through the first groove, the number of connection points between the first insulating member and the second insulating member can be increased, thereby improving the overall stability of the base plate structure.

[0009] In some embodiments, the first connecting portion is provided with at least one through hole penetrating the first and second insulating members along the thickness direction of the base plate. By providing the through hole, more venting channels and electrolyte wetting channels can be provided for the electrode assembly, and it also serves a positioning function when installing the base plate.

[0010] In some embodiments, the housing cavity has an opening, and the housing includes a bottom wall facing the opening; the battery cell also includes a pressure relief mechanism disposed on the bottom wall, and a bottom support plate is located between the bottom wall and the electrode assembly; wherein, the support member has a second groove disposed facing the pressure relief mechanism, and the second groove penetrates the support member along the thickness direction of the support member. By providing a second groove on the support member facing the pressure relief mechanism, the structural strength of the bottom support plate at the position facing the pressure relief mechanism can be weakened. When the internal pressure of the battery cell increases, gas can break through the second groove and be directly sprayed towards the pressure relief mechanism. This is more conducive to the gas generated at the electrode assembly passing through the bottom support plate to reach the pressure relief mechanism, thereby improving the pressure relief efficiency.

[0011] In some embodiments, the orthographic projection of the pressure relief mechanism falls entirely within the orthographic projection range of the second groove in a plane perpendicular to the thickness direction of the support member. Setting the pressure relief mechanism to fall entirely within the orthographic projection range of the second groove can shorten the gas exhaust path and improve exhaust efficiency.

[0012] In some embodiments, the support member has a protrusion on the side facing the bottom wall, which forms an airflow channel between the bottom wall and the support member. By adding the protrusion to form an airflow channel between the support member and the bottom wall, the flow of gas is improved. When the internal pressure of the battery cell increases, the gas generated at the electrode assembly can reach the pressure relief mechanism through the airflow channel, thereby improving the pressure relief efficiency.

[0013] In some embodiments, the orthographic projection of the protrusion is offset from the pressure relief mechanism in a plane perpendicular to the thickness direction of the support member. This offsetting arrangement of the protrusion and the pressure relief mechanism minimizes the risk of the protrusion blocking the pressure relief mechanism when the internal pressure of the battery cell increases, thereby improving the efficiency of pressure relief.

[0014] In some embodiments, the insulating coating comprises a ceramic material. In some embodiments, the insulating coating comprises a fluorocarbon polymer. In some embodiments, the insulating coating comprises both a ceramic material and a fluorocarbon polymer. The ceramic material includes one or more of alumina, zirconium oxide, silicon nitride, and silicon carbide; the fluorocarbon polymer includes one or more of polytetrafluoroethylene, fluorinated ethylene propylene copolymer, and fluororubber. When the support component can provide support, selecting a suitable insulating coating can balance mechanical strength and corrosion resistance, improving the isolation effect between the metal layer and the electrolyte.

[0015] In some embodiments, the thickness T1 of the insulating coating satisfies: 2μm≤T1≤8μm. Appropriately setting the thickness of the insulating coating can balance the requirements of both isolation and insulation, while preventing excessive thickness from increasing the brittleness of the insulating coating and affecting the mechanical properties of the base plate.

[0016] In some embodiments, the metal layer comprises aluminum, aluminum alloy, or steel. Selecting a suitable metal material to prepare the metal layer can balance the supporting strength and high-temperature resistance of the base plate, thereby improving the reliability of the base plate support.

[0017] In some embodiments, the thickness T2 of the metal layer satisfies: 0.1mm ≤ T2 ≤ 5mm. Appropriately selecting the thickness of the metal layer can balance the supporting performance of the base plate with the space arrangement requirements within the battery cell, thereby improving the overall performance of the battery cell.

[0018] In some embodiments, the melting point of the support member is higher than that of the first insulator and the second insulator. Increasing the melting point of the support member to be higher than that of the first and second insulators improves the high-temperature support capacity of the base plate, thereby enhancing the reliability of battery cell pressure relief.

[0019] In some embodiments, the first and second insulating components respectively comprise one or more of polypropylene, polyethylene terephthalate, and polyimide. When the support component can provide support, selecting a suitable insulating material can reduce the manufacturing cost of the base plate while meeting insulation requirements.

[0020] In some embodiments, the thickness T3 of the first insulating member satisfies: 0.1mm ≤ T3 ≤ 2mm. In some embodiments, the thickness T4 of the second insulating member satisfies: 0.1mm ≤ T4 ≤ 2mm. Appropriately selecting the thickness T3 of the first insulating member and the thickness T4 of the second insulating member can enhance the insulation performance of the base plate and meet the space arrangement requirements within the battery cell, thereby improving the overall performance of the battery.

[0021] In some embodiments, the capacity of a single battery cell is greater than or equal to 360 Ah. The base plate adopted in this application embodiment can better meet the support requirements of such large-capacity battery cells, reduce the risk of electrode assembly collapse and blockage of venting channels, and improve the reliability of pressure relief and venting of the battery cell.

[0022] An embodiment of the second aspect of this application provides a battery device that includes the battery cell described in the above embodiments.

[0023] An embodiment of the third aspect of this application provides an electrical device that includes the battery device described in the above embodiments, the battery device being used to provide electrical energy.

[0024] An embodiment of the fourth aspect of this application provides an energy storage device that includes a plurality of battery cells or battery devices as described in the above embodiments, wherein the battery cells or battery devices are used to store or provide electrical energy.

[0025] An embodiment of the fifth aspect of this application provides an energy storage system, which includes a power conversion device and the energy storage device in the above embodiments, wherein the power conversion device is used to electrically connect a power generation device and an energy storage device.

[0026] An embodiment of the sixth aspect of this application provides a charging network including a charging pile and an energy storage device or energy storage system as described in the above embodiments, wherein the energy storage device or energy storage system is used to provide electrical energy to the charging pile.

[0027] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0028] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0029] Figure 1 This is an exploded view of the battery device provided in some embodiments of this application;

[0030] Figure 2 This application provides schematic diagrams of the structure of an energy storage system according to some embodiments.

[0031] Figure 3 This is a schematic diagram of the structure of a charging network provided in some embodiments of this application;

[0032] Figure 4 This is an exploded structural diagram of a battery cell provided in some embodiments of this application;

[0033] Figure 5 An exploded structural diagram of the base plate provided in some embodiments of this application;

[0034] Figure 6 This is a schematic diagram of the thickness direction structure of the base plate provided in some embodiments of this application;

[0035] Figure 7 for Figure 4 A bottom view along direction B;

[0036] Figure 8 for Figure 7 A cross-sectional view along the AA direction.

[0037] Explanation of reference numerals in the attached figures:

[0038] 100. Battery device; 200. Energy storage device; 300. Power conversion device; 400. Power generation equipment; 500. Charging pile; 600. Connector; 10. Housing; 11. First part; 12. Second part; 20. Battery cell; 21. End cap; 211. Electrode terminal; 22. Housing; 221. Bottom wall; 222. Pressure relief mechanism; 23. Electrode assembly; 231. Electrode tab; 24. Bottom support plate; 241. First insulating component; 2411. First groove; 242. Second insulating component; 2421. Second groove; 243. First connecting part; 244. Through hole; 245. Second connecting part; 25. Support component; 251. Metal layer; 252. Insulating coating; 253. First groove; 254. Second groove; 255. Protrusion. Detailed Implementation

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

[0040] 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.

[0041] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0042] 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.

[0043] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0044] 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).

[0045] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0046] 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.

[0047] Currently, the application of rechargeable batteries is becoming increasingly widespread, judging from market trends. They are not only used in energy storage systems for hydropower, thermal power, wind power, and solar power plants, but also extensively in various electronic devices, such as electric bicycles, electric motorcycles, and electric vehicles, as well as in military equipment and aerospace. As the application areas of rechargeable batteries continue to expand, the market demand is also constantly increasing.

[0048] A base plate can be installed inside the battery casing to support the electrode assembly, allowing it to avoid the corners and bends of the casing and creating an airflow channel for gas release during depressurization. However, in the event of a battery safety malfunction such as overcharging or thermal runaway, the internal temperature of the battery cell rises. The base plate is typically made of insulating materials such as polypropylene (PP) or polyethylene terephthalate (PET), which melt at high temperatures. This can cause the electrode assembly to collapse due to insufficient support, further damaging the electrode assembly and blocking the gas release channel within the casing. This prevents the gas inside the battery cell from escaping in a timely manner, thus affecting the reliability of the battery cell depressurization.

[0049] In some embodiments, the base plate includes a metal support layer, which prevents the metal support layer from melting when high temperatures are generated inside the battery cell. This can improve the support capacity of the base plate, thereby reducing the risk of electrode assembly collapse and helping to maintain the unobstructed air venting channels inside the casing. However, when the material of the metal support layer of the base plate is different from the metal material of the battery casing, metal electrochemical corrosion may occur under the action of electrolyte, which may lead to failure of the base plate or battery casing structure and affect the reliability of the battery cell structure.

[0050] To address the above problems, an embodiment of the first aspect of this application provides a battery cell, which includes an electrode assembly, a housing, and a base plate. The housing has a receiving cavity for accommodating the electrode assembly. The base plate is located between the electrode assembly and the inner wall of the housing and is used to support the electrode assembly. The base plate includes a support member, which includes a metal layer and an insulating coating covering the outer surface of the metal layer.

[0051] By covering the outer surface of the metal layer with an insulating coating, the metal layer can be isolated and insulated from the electrode assembly and the housing. This helps prevent the metal layer and the housing from undergoing electrochemical corrosion under the action of the electrolyte. At the same time, the metal layer has better mechanical properties, which can better support the electrode assembly and improve the reliability of the battery cell structure.

[0052] The battery cells disclosed in this application can be used, but are not limited to, in electrical devices or energy storage devices such as vehicles, ships, or aircraft. A power system comprising the electrical device or energy storage device can be constructed using the battery cells and batteries disclosed in this application, which helps to improve the reliability of the battery cell structure.

[0053] This application provides an electrical device that uses a battery as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0054] For ease of explanation, the following embodiments use a battery device according to an embodiment of this application as an example.

[0055] Please refer to Figure 1 , Figure 1This is an exploded structural diagram of a battery device provided in some embodiments of this application. The battery device 100 includes a housing 10 and a battery cell 20, with the battery cell 20 housed within the housing 10. The housing 10 provides a space for the battery cell 20 and can have various structures. In some embodiments, the housing 10 may include a first portion 11 and a second portion 12, which overlap each other, jointly defining a space for accommodating the battery cell 20. The second portion 12 may be a hollow structure with one open end, and the first portion 11 may be a plate-like structure, covering the open side of the second portion 12 so that the first portion 11 and the second portion 12 jointly define the space. Alternatively, the first portion 11 and the second portion 12 may both be hollow structures with one open side, with the open side of the first portion 11 covering the open side of the second portion 12. Of course, the housing 10 formed by the first portion 11 and the second portion 12 can have various shapes, such as a cylinder, a cuboid, etc.

[0056] In the battery device 100, there can be multiple battery cells 20, which can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 20 are connected in both series and parallel connections. Multiple battery cells 20 can be directly connected in series, parallel, or in a mixed configuration, and then the entire assembly of the multiple battery cells 20 is housed within the housing 10. Alternatively, the battery device 100 can also consist of multiple battery cells 20 first connected in series, parallel, or in a mixed configuration to form battery modules, and then these battery modules are connected in series, parallel, or in a mixed configuration to form a whole, which is also housed within the housing 10. The battery device 100 may also include other structures; for example, it may include a busbar component for electrical connection between the multiple battery cells 20.

[0057] Each battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited to these. The battery cell 20 can be cylindrical, flat, cuboid, or other shapes.

[0058] Please refer to Figure 2 , Figure 2This is a schematic diagram of the structure of an energy storage system provided in some embodiments of this application. Embodiments of this application provide an energy storage device 200, including one or more battery clusters to increase the voltage and capacity of the energy storage device 200. A battery cluster may include multiple battery devices 100, which are connected in series via a busbar to increase the voltage of the energy storage device 200. When the energy storage device 200 includes multiple battery clusters, the multiple battery clusters are connected in parallel to increase the capacity of the energy storage device 200. The energy storage device 200 can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems, or temporary power supply systems, etc. The energy storage device 200 can store electrical energy as needed and output electrical energy when appropriate. For example, the energy storage device 200 can store electrical energy during off-peak hours and provide electrical energy to relevant users or electrical equipment during peak hours. The energy storage system provided in this application can be any power system that requires the energy storage device 200. In some embodiments, the energy storage device 200 is an energy storage container or an energy storage cabinet.

[0059] In some embodiments, the energy storage device 200 may include a cabinet and one or more battery clusters housed in the cabinet.

[0060] In some embodiments, the energy storage device 200 may include modules such as a thermal management module, a main control module, a central control module, a power distribution module, and a fire protection module.

[0061] As an example, the thermal management module may include a liquid cooling unit that supplies coolant to each battery device 100 via piping to regulate the temperature of the individual battery cells 20.

[0062] As an example, the main control module can serve as the battery management unit for the battery cluster, used to monitor and manage the battery cluster. The main control module can monitor information such as the current, voltage, power, or temperature of the battery cluster. For instance, it can control the charging and discharging current and voltage of the battery cluster. The main control module includes modules such as an auxiliary battery management unit (SBMU) and a fusion switch.

[0063] As an example, the central control module can serve as the battery management unit of the energy storage device 200, used to monitor and manage the energy storage device 200. The central control module can monitor information such as the current, voltage, power, state of charge, or temperature of the energy storage device 200. For example, it can control the charging and discharging current and voltage of the energy storage device 200. As an example, the central control module includes modules such as an insulation monitoring module (IMM), a master battery management unit (MBMU), an Ethernet (ETH) module, and a fiber optic conversion module.

[0064] As an example, a fire protection system includes control panels, detectors, alarm devices, etc., used to detect, alarm, or extinguish fires in energy storage systems.

[0065] As an example, the power distribution unit can be used to distribute power to the power modules of the energy storage device 200.

[0066] In some embodiments, the energy storage system may include one or more energy storage devices 200 and a power converter system (PCS), wherein the power converter system 300 is connected between the power generation device 400 and the energy storage device 200. The power generation device 400 generates electrical energy, which can be stored in the energy storage device 200 via the power converter system 300, and the electrical energy stored in the energy storage device 200 can be released back to the power generation device 400 via the power converter system 300. As an example, the power generation device 400 may specifically be a power grid, solar panels, hydroelectric power generation equipment, thermal power generation equipment, wind power generation equipment, etc. The specific type of the power generation device 400 is not limited in this application.

[0067] Please refer to Figure 3 , Figure 3 This is a schematic diagram of the structure of a charging network provided in some embodiments of this application. Embodiments of this application provide a charging network including a charging pile 500 and an energy storage device 200. The charging pile 500 is electrically connected to the energy storage device 200, which provides electrical energy to the charging pile 500. The charging pile 500 is electrically connected to a battery device 100 in the energy storage device 200 via a cable, and the battery device 100 can provide its stored electrical energy to the charging pile 500. The charging pile 500 has one or more connectors 600 for connecting to an electrical device (such as a vehicle), thereby enabling it to replenish energy.

[0068] The energy storage device 200 can be located inside the charging pile 500 (e.g., an integrated energy storage and charging unit) or outside the charging pile 500.

[0069] Please refer to Figure 4 , Figure 4 This is an exploded structural diagram of a battery cell provided in some embodiments of this application. The battery cell 20 refers to the smallest unit that makes up the battery. For example... Figure 4 The battery cell 20 includes an end cap 21, a housing 22, an electrode assembly 23, and other functional components.

[0070] End cap 21 refers to a component that covers the opening of housing 22 to isolate the internal environment of battery cell 20 from the external environment. The shape of end cap 21 can be adapted to the shape of housing 22 to fit it. Optionally, end cap 21 can be made of a material with certain hardness and strength (such as aluminum alloy), so that end cap 21 is not easily deformed under pressure and impact, giving battery cell 20 higher structural strength and improved safety performance. Functional components such as electrode terminals 211 can be provided on end cap 21. Electrode terminals 211 can be used for electrical connection with electrode assembly 23 for outputting or inputting electrical energy to battery cell 20. In some embodiments, end cap 21 can also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of battery cell 20 reaches a threshold. The material of end cap 21 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this. In some embodiments, an insulating element may be provided on the inner side of the end cap 21. The insulating element can be used to isolate the electrical connection components within the housing 22 from the end cap 21 to reduce the risk of short circuits. For example, the insulating element may be made of plastic, rubber, etc.

[0071] The housing 22 is a component used to cooperate with the end cap 21 to form the internal environment of the battery cell 20. This internal environment can accommodate the electrode assembly 23, electrolyte, and other components. The housing 22 and the end cap 21 can be independent components. An opening can be provided on the housing 22, and the end cap 21 can be used to close the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 21 and the housing 22 can be integrated. Specifically, the end cap 21 and the housing 22 can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 22, the end cap 21 closes the housing 22. The housing 22 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 22 can be determined according to the specific shape and size of the electrode assembly 23. The material of the housing 22 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. This application embodiment does not impose any special limitations on this.

[0072] Electrode assembly 23 is the component in the battery cell 20 where electrochemical reactions occur. The casing 22 may contain one or more electrode assemblies 23. The electrode assembly 23 is mainly formed by winding or stacking positive and negative electrode plates, and typically a separator is provided between the positive and negative electrode plates. The portions of the positive and negative electrode plates containing active material constitute the main body of the electrode assembly, while the portions of the positive and negative electrode plates without active material each constitute a tab 231. The positive and negative tabs may be located together at one end of the main body or separately at both ends of the main body. During the charging and discharging process of the battery, the positive and negative active materials react with the electrolyte, and the tabs 231 connect to the electrode terminals to form a current loop.

[0073] This application provides a battery cell 20, which includes a housing 22, an electrode assembly 23, and a bottom support plate 24. The housing 22 has a receiving cavity for accommodating the electrode assembly 23. The bottom support plate 24 is located between the electrode assembly 23 and the inner wall of the housing 22 and is used to support the electrode assembly 23. The bottom support plate 24 includes a support member 25, which includes a metal layer 251 and an insulating coating 252 covering the outer surface of the metal layer.

[0074] like Figure 5 and Figure 6 As shown, the base plate 24 has a multi-layer composite structure. Specifically, the base plate 24 includes a support member 25, which includes a metal layer 251. For example, the metal layer 251 is a planar thin plate structure, and along the thickness direction of the base plate 24, that is... Figure 6 In the X direction shown, the metal layer 251 has an insulating coating 252 on the side facing the electrode assembly 23. The insulating coating 252 at this location can isolate the metal layer 251 from the bottom of the electrode assembly 23, preventing short circuits caused by contact between the electrode assembly 23 and the metal layer 251. The metal layer 251 also has an insulating coating 252 on the side facing away from the electrode assembly 23. The insulating coating 252 at this location is located between the metal layer 251 and the inner wall of the housing, and can isolate the metal layer 251 from the bottom of the inner wall of the housing. The insulating coating 252 at this location can be in direct or indirect contact with the inner wall of the housing.

[0075] The insulating coating 252 is a layered structure that can serve as an insulator and insulator. The insulating coating 252 is located on the outer surface of the metal layer 251 and completely covers the metal layer 251. The method of forming the insulating coating 252 is not limited, such as spraying to form the insulating coating 252, sintering to form the insulating coating 252, etc.

[0076] The metal layer 251 can enhance the structural strength of the support, thereby improving the support capacity of the base plate 24. The metal layer 251 is completely covered by the insulating coating 252, which can separate the metal layer 251 from the electrode assembly 23 and the housing 22. The metal layer 251 does not come into contact with the electrode assembly 23, the housing 22 and the electrolyte, reducing the risk of short circuit and electrochemical corrosion.

[0077] In related technologies, base plates made of non-metallic materials such as polyethylene terephthalate (PET) may melt due to high temperatures when thermal runaway occurs inside the battery cell 20, causing the electrode assembly 23 to collapse. In this embodiment, the base plate 24 uses a support 25 made of a more heat-resistant metal layer 251, which can maintain support for the electrode assembly 23 even during thermal runaway, achieving more reliable support.

[0078] By providing an insulating coating 252 on the outer surface of the metal layer 251, the metal layer 251 can be isolated and insulated from the electrode assembly 23 and the housing 22. This helps to prevent the metal layer 251 and the housing 22 from undergoing electrochemical corrosion under the action of the electrolyte. Furthermore, the metal layer 251 can provide reliable support at high temperatures, thereby improving the reliability of the battery cell 20 structure.

[0079] According to some embodiments of this application, the base plate 24 further includes a first insulating member 241 and a second insulating member 242. The first insulating member 241 is located on the side surface of the support member 25 facing the electrode assembly 23, and the second insulating member 242 is located on the side surface of the support member 25 facing away from the electrode assembly 23. The first insulating member 241 and the second insulating member 242 are connected along the outer periphery of the support member 25 so as to completely cover the support member 25 between the first insulating member 241 and the second insulating member 242.

[0080] like Figures 6 to 8 As shown, the base plate 24 is a multi-layered composite structure including insulating elements. In some embodiments, the first insulating element 241, the support element 25, and the second insulating element 242 are all planar thin plate structures, and are along the thickness direction of the base plate 24, i.e. Figure 6 In the X direction shown, the first insulating member 241, the support member 25 and the second insulating member 242 are stacked, wherein the first insulating member 241 is located on the upper surface of the support member 25 and contacts the bottom of the electrode assembly 23, and the second insulating member 242 is located on the lower surface of the support member 25.

[0081] The support member 25 is sandwiched between the first insulating member 241 and the second insulating member 242. The outer circumference of the first insulating member 241 and the second insulating member 242 can be set to be larger than the outer circumference of the support member 25, so that a part of them can extend beyond the outer circumference of the support member 25. The part of the first insulating member 241 that extends beyond the support member 25 can directly contact the part of the second insulating member 242 that extends beyond the support member 25 for connection.

[0082] The connection along the outer periphery of the support member 25 refers to a continuous connection around the outer edge of the support member 25, so that the support member 25 can completely cover the space between the first insulating member 241 and the second insulating member 242. The specific connection method can be set as needed, for example, it can be achieved by heat fusion or adhesive bonding.

[0083] The first insulating element 241 and the second insulating element 242 can be made of the same insulating material or different insulating materials.

[0084] In some embodiments, the first insulating member 241, the support member 25, and the second insulating member 242 can be fixed to each other by any feasible connection method, such as by bonding or heat fusion, thereby forming an integral component and installing it between the housing 22 and the electrode assembly 23.

[0085] For example, the first insulating member 241 and the second insulating member 242 are respectively bonded to the insulating coating 252 of the support member 25. For example, the outer periphery of the first insulating member 241 is bonded to the outer periphery of the second insulating member 242, and the support member 25 is enclosed in the cavity formed by the first insulating member 241 and the second insulating member 242.

[0086] In some embodiments, other functional layers, such as adhesive layers, may be provided between the first insulating member 241 and the support member 25, and between the second insulating member 242 and the support member 25 as needed.

[0087] In this embodiment, the first insulating element 241 and the second insulating element 242 are sleeved on the outer surface of the support member 25, serving as the first layer of insulation between the base plate 24 and the housing 22, and as the first layer of isolation between the base plate 24 and the electrolyte. The insulating coating 252 serves as the second layer of insulation and the second layer of isolation after the first layer of insulation fails, improving the reliability of the support of the base plate 24. In addition, since the support member 25 containing the metal layer 251 has high hardness, the external first insulating element 241 and the second insulating element 242 can alleviate the friction between the base plate 24 and the interior of the housing 22, reducing the risk of debris generation and the insulation failure of the insulating coating 252 on the surface of the metal layer 251 due to cracking.

[0088] According to some embodiments of this application, the support member 25 is provided with at least one first groove 253 extending through the support member 25 along the thickness direction of the support member 25, and the first insulating member 241 and the second insulating member 242 are connected at the position of the first groove 253 to form a first connecting portion 243.

[0089] like Figure 5 and Figure 8 As shown, the first groove 253 is a through groove that penetrates the support member 25. The shape of the first groove 253 can be arbitrarily set as needed, for example, it can be circular, elliptical, or polygonal. The number of first grooves 253 can be one or more, and this application does not limit this. In some embodiments, the support member 25 includes a plurality of elongated first grooves 253 extending in different directions and spaced apart along the length direction of the support member 25.

[0090] Both the first insulating member 241 and the second insulating member 242 are planar thin plate structures. They can contact each other and connect to form the first connecting part 243 at the location of the first groove 253. The specific connection method can be any feasible connection method, such as heat fusion connection or bonding.

[0091] By opening a first groove 253 on the support member 25 and connecting the first insulating member 241 and the second insulating member 242 through the first groove 253, the connection points between the first insulating member 241 and the second insulating member 242 can be increased, thereby improving the overall stability of the base plate 24.

[0092] According to some embodiments of this application, the first connecting portion 243 is provided with at least one through hole 244 that penetrates the first insulating member 241 and the second insulating member 242 along the thickness direction of the base plate 24.

[0093] like Figure 5 and Figure 8 As shown, the through hole 244 is located within the first groove 253, penetrating the first insulating member 241 and the second insulating member 242 respectively. The number of through holes 244 can be one or more, depending on actual needs. The shape of the through hole 244 can be arbitrary, such as circular, elliptical, or polygonal. The through hole 244 enables fluid communication between the spaces on both sides of the base plate 24.

[0094] It should be noted that the inner wall surface of the through hole 244 is the first insulating member 241 and the second insulating member 242, which isolate the support member 25 from the space of the through hole 244.

[0095] By setting through holes 244, more venting channels and electrolyte wetting channels can be provided for the electrode assembly 23. On the other hand, it plays a positioning role when installing the base plate 24.

[0096] According to some embodiments of this application, the housing 22 has an opening in its receiving cavity, and the housing 22 includes a bottom wall 221 facing the opening; the battery cell 20 also includes a pressure relief mechanism 222 disposed on the bottom wall 221, and a bottom support plate 24 is located between the bottom wall 221 and the electrode assembly 23; wherein, the support member 25 is provided with a second groove 254 disposed facing the pressure relief mechanism 222, and the second groove 254 penetrates the support member 25 along the thickness direction of the support member 25.

[0097] The housing 22 can be formed into an open receiving cavity by stamping, and the end cap 21 can be connected to the housing 22 by covering the opening, thereby forming a closed receiving cavity for accommodating the electrode assembly 23.

[0098] The housing 22 includes a bottom wall 221 facing the opening and a side wall adjacent to the opening. The bottom wall 221 and the side wall are bent together, and the bottom support plate 24 is engaged at the bend to prevent the electrode assembly 23 from being squeezed by the bend. A small cavity that allows airflow can be formed between the bottom support plate 24 and the bottom wall 221. The pressure relief mechanism 222 is disposed on the bottom wall 221. When the internal pressure of the battery cell is too high, the gas can flow through the space between the bottom support plate 24 and the bottom wall 221 to the location of the pressure relief mechanism 222, causing the pressure relief mechanism 222 located on the bottom wall 221 to break open and allow the gas to be ejected, thereby achieving pressure relief.

[0099] The pressure relief mechanism 222 can be an independent explosion-proof valve welded into the mounting hole of the bottom wall 221, or it can be an integrated explosion-proof valve directly installed on the bottom wall 221 and integrated with the bottom wall 221. For example, a groove can be provided on the surface of the bottom wall 221 and serve as a pressure relief mechanism 222 that can relieve pressure.

[0100] The second groove 254 can be a through groove of any shape. In some embodiments, the shape of the second groove 254 can correspond to that of the pressure relief mechanism 222, for example, the two have the same shape and size. The second groove 254 and the pressure relief mechanism 222 are directly opposite each other, meaning that along the direction perpendicular to the surface of the bottom wall 221, the orthographic projection of the second groove 254 on the upper surface of the bottom wall 221 at least partially overlaps with the orthographic projection of the pressure relief mechanism 222 on the upper surface of the bottom wall 221.

[0101] In some embodiments, such as Figure 8 As shown, the first insulating member 241 and the second insulating member 242 can also be connected at the position of the second groove 254. The two can contact each other at the position of the second groove 254 and connect to each other to form a second connecting part 245. The specific connection method can be the same as the connection method at the first groove 253, or it can be different. For example, it can be heat-fused or bonded.

[0102] In some embodiments, the second groove 254 merely penetrates the support member 25, while the first insulating member 241 and the second insulating member 242 may be completely and continuously positioned in the second groove 254. In other embodiments, such as... Figure 5 As shown, at least one of the first insulating member 241 and the second insulating member 242 may also have some weak structures provided at the position corresponding to the second groove 254. The weak structures may be partially recessed grooves or engravings, or they may be completely through grooves.

[0103] For example, a first groove 2411 is provided on the first insulating member 241, and a second groove 2421 is provided on the second insulating member 242. The shape and number of the first groove 2411 and the second groove 2421 can be set according to actual needs, and this application does not impose any restrictions. In a plane perpendicular to the thickness direction of the support member 25, the orthographic projection of the first groove 2411 and the orthographic projection of the second groove 2421 coincide with each other, and both the orthographic projections of the first groove 2411 and the second groove 2421 fall completely within the orthographic projection range of the second groove 254. This helps to reduce the resistance that the airflow needs to overcome to break through the bottom support plate 24, facilitates the directional guidance of gas ejection, and improves the reliability and accuracy of pressure relief.

[0104] By providing a second groove 254 on the support member 25 that is directly opposite the pressure relief mechanism 222, the structural strength of the bottom support plate 24 at the position directly opposite the pressure relief mechanism 222 can be weakened. When the internal pressure of the battery cell increases, the gas can break through the second groove 254 and be directly sprayed toward the pressure relief mechanism 222. This makes it easier for the gas generated at the electrode assembly 23 to pass through the bottom support plate 24 and reach the pressure relief mechanism 222, thereby improving the pressure relief efficiency.

[0105] According to some embodiments of this application, in a plane perpendicular to the thickness direction of the support member 25, the orthographic projection of the pressure relief mechanism 222 falls entirely within the orthographic projection range of the second groove 254.

[0106] In some embodiments, the plane perpendicular to the thickness direction of the support member 25 is any plane perpendicular to the X direction. The projected area of ​​the second groove 254 in the plane perpendicular to the thickness direction of the support member 25 is greater than the projected area of ​​the pressure relief mechanism 222 in the plane, and the projected pattern of the pressure relief mechanism 222 is completely within the range of the projected pattern of the second groove 254.

[0107] like Figure 7 As shown, the pressure relief mechanism 222 is an "H" shaped pattern formed by the grooves on the bottom wall 221, and the second groove 254 is a rectangular groove. When viewed from the outside of the bottom wall 221 of the housing 22, the pressure relief mechanism 222 is completely located within the projection range of the second groove 254.

[0108] Setting the pressure relief mechanism 222 to fall entirely within the orthographic projection range of the second groove 254 can shorten the gas exhaust path and improve exhaust efficiency.

[0109] According to some embodiments of this application, the support member 25 is provided with a protrusion 255 on the side facing the bottom wall 221, and the protrusion 255 is used to form an airflow channel between the bottom wall 221 and the support member 25.

[0110] like Figure 7 As shown, the protrusion 255 is located on the side of the support member 25 facing the bottom wall 221, and is a structure used to form a gas channel between the body of the support member 25 and the bottom wall 221. The protrusion 255 is in direct contact with the bottom wall 221 or indirect contact, for example, the protrusion 255 is in indirect contact with the bottom wall 221 through the second insulating member 242.

[0111] The protrusion 255 can be a long strip protrusion extending along the length or width of the support member 25, or it can be an annular protrusion arranged around the second groove 254.

[0112] By adding a protrusion 255 to form an airflow channel between the support 25 and the bottom wall 221, the flow of gas is improved. When the internal pressure of the battery cell increases, the gas generated at the electrode assembly 23 can reach the pressure relief mechanism 222 through the airflow channel, thereby improving the pressure relief efficiency.

[0113] According to some embodiments of this application, in a plane perpendicular to the thickness direction of the support member 25, the orthographic projection of the protrusion 255 is offset from the pressure relief mechanism 222.

[0114] In some embodiments, the plane perpendicular to the thickness direction of the support member 25 is any plane perpendicular to the X direction, and the projection pattern of the protrusion 255 in the plane perpendicular to the thickness direction of the support member 25 is offset from the projection pattern of the pressure relief mechanism 222 in the same plane.

[0115] In some embodiments, such as Figure 7 As shown, along the length of the support member 25, two protrusions 255 are arranged on both sides of the second groove 254. The two protrusions 255 on each side of the second groove 254 are arranged at intervals along the width of the support member 25 and extend along the length of the support member 25. An airflow channel is formed between the two protrusions 255, the support member 25 and the bottom wall 221. The pressure relief mechanism 222 is an "H" shaped pattern formed by the grooves on the bottom wall 221. When viewed from the outside of the bottom wall 221 of the housing 22, the pressure relief mechanism 222 and the protrusions 255 are not connected to each other.

[0116] By staggering the protrusion 255 and the pressure relief mechanism 222, the protrusion 255 is prevented from blocking the pressure relief mechanism 222 as much as possible when the internal pressure of the battery cell increases, thereby improving the pressure relief efficiency.

[0117] According to some embodiments of this application, the insulating coating 252 comprises a ceramic material. In some embodiments, the insulating coating 252 comprises a fluorocarbon polymer. In some embodiments, the insulating coating 252 comprises a ceramic material and a fluorocarbon polymer. The ceramic material comprises one or more of alumina (Al2O3), zirconium oxide (ZrO2), silicon nitride (Si3N4), and silicon carbide (SiC); the fluorocarbon polymer comprises one or more of polytetrafluoroethylene (PTFE), fluorinated ethylene propylene copolymer (FEP), and fluororubber.

[0118] The insulating coating 252 can be a ceramic coating, such as alumina (Al2O3), zirconium oxide (ZrO2), silicon nitride (Si3N4), and silicon carbide (SiC). It can also be any mixture of the above.

[0119] The insulating coating 252 can be a fluorocarbon polymer coating, such as tetrafluoroethylene (PTFE), fluorinated ethylene propylene copolymer (FEP), and fluororubber. It can also be any mixture of the above.

[0120] The insulating coating 252 can be a composite coating comprising a ceramic coating and a fluorocarbon polymer coating, such as alumina (Al2O3) and tetrafluoroethylene (PTFE).

[0121] When the support member 25 can provide support, selecting a suitable insulating coating 252 can balance mechanical strength and corrosion resistance, and improve the isolation effect between the metal layer 251 and the electrolyte.

[0122] According to some embodiments of this application, the thickness T1 of the insulating coating 252 satisfies: 2μm≤T1≤8μm.

[0123] An insulating coating 252 covers the outer surface of the metal layer 251, and its thickness T1 can be determined according to the isolation requirements, insulation requirements, and material type. In some embodiments, the thickness T1 of the insulating coating 252 can be 2μm, 2.5μm, 3μm, 3.5μm, 4μm, 4.5μm, 5μm, 5.5μm, 6μm, 6.5μm, 7μm, 7.5μm, 8μm, or any value between any two adjacent values ​​mentioned above.

[0124] By setting the thickness of the insulating coating 252 appropriately, the requirements for both isolation and insulation can be met, while preventing the insulating coating 252 from becoming too thick, which would increase its brittleness and affect the mechanical properties of the base plate 24.

[0125] According to some embodiments of this application, the metal layer 251 includes aluminum, aluminum alloy, or steel.

[0126] The metal layer 251 can be made of a metal material that meets the support requirements, such as aluminum, aluminum alloy, or steel. Since the metal layer 251 is covered by the insulating coating 252, it will not directly contact the electrode assembly 23 and the housing 22, thus eliminating the risk of short circuits. Simultaneously, the insulating coating 252 also isolates the electrolyte from the metal layer 251, eliminating the risk of dissimilar metal electrochemical corrosion between the metal layer 251 and the housing 22.

[0127] Selecting a suitable metal material to prepare the metal layer 251 can balance the supporting strength and high temperature resistance of the base plate 24, thereby improving the reliability of the support of the base plate 24.

[0128] According to some embodiments of this application, the thickness T2 of the metal layer 251 satisfies: 0.1mm≤T2≤5mm.

[0129] The metal layer 251 is flat, and its thickness T2 can be determined according to the support requirements and material type. In some embodiments, the thickness T2 of the metal layer 251 can be 0.1mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 2mm, 2.2mm, 2.5mm, 3mm, 3.2mm, 3.5mm, 4mm, 4.2mm, 4.5mm, 5mm, or any value between any two adjacent values ​​mentioned above.

[0130] By appropriately selecting the thickness of the metal layer 251, the supporting performance of the bottom support plate 24 and the space arrangement requirements within the battery cell 20 can be balanced, thereby improving the overall performance of the battery cell 20.

[0131] According to some embodiments of this application, the melting point of the support member 25 is higher than the melting point of the first insulating member 241 and the melting point of the second insulating member 242.

[0132] Melting point is the temperature at which a substance changes from a solid to a liquid state. In some embodiments, the base plate is made of an insulating material (such as polypropylene). In the event of a battery safety failure, the internal temperature of the battery is high, which may exceed the melting point of some materials, such as polypropylene, causing the base plate to melt.

[0133] In the embodiments of this application, since the supporting member 25 has a stronger supporting capacity than the first insulating member 241 and the second insulating member 242, and the melting point of the supporting member 25 is set to be higher than the melting point of the first insulating member 241 and the second insulating member 242, the bottom plate 24 can still maintain a certain degree of structural integrity in a high-temperature environment, thereby maintaining the supporting function of the bottom plate 24.

[0134] By setting the melting point of the support member 25 higher than that of the first insulating member 241 and the second insulating member 242, the high-temperature support capacity of the base plate 24 can be improved, thereby enhancing the reliability of the battery cell 20 pressure relief.

[0135] According to some embodiments of this application, the first insulating member 241 and the second insulating member 242 respectively comprise one or more of polypropylene (PP), polyethylene terephthalate (PET), and polyimide (PI).

[0136] The first insulating element 241 and the second insulating element 242 can be made of PP, PET or PI, or they can be mixtures, such as mixtures of PP and PET, mixtures of PP and PI, mixtures of PET and PI, and mixtures of PP, PET and PI, etc.

[0137] The material of the first insulating element 241 and the material of the second insulating element 242 can be the same or different.

[0138] If the support member 25 can provide support, selecting a suitable insulation material can reduce the manufacturing cost of the base plate 24 while meeting insulation requirements.

[0139] According to some embodiments of this application, the thickness T3 of the first insulating member 241 satisfies: 0.1mm ≤ T3 ≤ 2mm. In some embodiments, the thickness T4 of the second insulating member 242 satisfies: 0.1mm ≤ T4 ≤ 2mm.

[0140] The thickness T3 of the first insulating element 241 can specifically be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, or 2mm, or any value between any two adjacent values ​​mentioned above.

[0141] The thickness T4 of the second insulating element 242 can specifically be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, or 2mm, or any value between any two adjacent values ​​mentioned above.

[0142] The thickness T3 of the first insulating member 241 and the thickness T4 of the second insulating member 242 can be the same or different, and this embodiment does not impose any restrictions on this.

[0143] In some embodiments, in the base plate 24, the thickness T3 of the first insulating member 241 and the thickness T4 of the second insulating member 242 are both less than the thickness of the support member 25.

[0144] By rationally selecting the thickness T3 of the first insulating component 241 and the thickness T4 of the second insulating component 242, the insulation performance of the base plate 24 and the space arrangement requirements within the battery cell 20 can be enhanced, thereby improving the overall performance of the battery.

[0145] According to some embodiments of this application, the capacity of the battery cell 20 is greater than or equal to 360Ah.

[0146] The capacity of a single battery cell 20 refers to the total amount of charge that a single battery cell 20 can release under certain discharge conditions, and is usually expressed in ampere-hours (Ah) or milliampere-hours (mAh).

[0147] It is understood that the capacity claimed in the embodiments of this application refers to the rated capacity of a single battery cell. For example, for lithium batteries, the rated capacity can be determined with reference to the provisions of Chinese standard GB / T18287-2000, or it can be determined according to the minimum capacity tested under the IEC61960 standard test conditions.

[0148] The large-capacity battery cell 20 produces more gas during thermal runaway. The bottom support plate 24 of this application embodiment can better meet the support requirements of such large-capacity battery cells 20, reduce the risk of electrode assembly 23 collapsing and blocking the exhaust channel, and improve the reliability of the battery cell 20 for depressurization and exhaust.

[0149] This application provides a battery device 100, which includes the battery cell 20 in the above embodiments.

[0150] The battery device 100 in this embodiment has the same technical effect as the battery cell 20 in the above embodiment, and will not be described again here.

[0151] This application provides an electrical device that includes the battery device 100 described in the above embodiments, which is used to provide electrical energy.

[0152] The power device in this embodiment uses the battery device 100 in the above embodiment, and therefore has the same technical effect, which will not be described again here.

[0153] This application provides an energy storage device 200, which includes a plurality of battery cells 20 or battery devices 100 as described in the above embodiments. The battery cells 20 or battery devices 100 are used to store or provide electrical energy.

[0154] The energy storage device 200 in this embodiment has the same technical effect as the battery cell 20 or battery device 100 in the above embodiment, and will not be described again here.

[0155] This application provides an energy storage system, which includes a power conversion device and an energy storage device 200 as described in the above embodiments. The power conversion device is used to electrically connect a power generation device and an energy storage device 200.

[0156] The energy storage system in this embodiment has the same technical effect as the energy storage device 200 in the above embodiment, and will not be described again here.

[0157] This application provides a charging network including a charging pile 500 and an energy storage device 200 or an energy storage system as described in the above embodiments. The energy storage device 200 is used to provide electrical energy to the charging pile 500.

[0158] The charging network in this embodiment has the same technical effect as the energy storage device or above energy storage system in the above embodiments, and will not be described again here.

[0159] The present application will be further described below with reference to a specific embodiment.

[0160] like Figures 4 to 8 As shown, the battery cell 20 includes an end cap 21, a housing 22, an electrode assembly 23, and a base plate 24.

[0161] The housing 22 has an opening in the receiving cavity; the housing 22 includes a bottom wall 221 facing the opening and a side wall adjacent to the opening; the bottom wall 221 is provided with a pressure relief mechanism 222, wherein the pressure relief mechanism 222 may be formed by a groove provided on the outer surface of the bottom wall 221.

[0162] Electrode assembly 23 is disposed within the receiving cavity of housing 22. End cap 21 closes to the opening of the receiving cavity.

[0163] The base plate 24 is located between the electrode assembly 23 and the bottom wall 221 and is used to support the electrode assembly 23. The base plate 24 includes a first insulating member 241, a support member 25 and a second insulating member 242 arranged along the thickness direction of the base plate 24. The first insulating member 241 is located on the side surface of the support member 25 facing the electrode assembly 23, and the second insulating member 242 is located on the side surface of the support member 25 away from the electrode assembly 23.

[0164] The support member 25 is provided with at least one first groove 253 extending through the support member 25 along the thickness direction of the support member 25, and the first insulating member 241 and the second insulating member 242 are connected at the position of the first groove 253 to form a first connecting part 243.

[0165] The support member 25 is provided with a second groove 254 that is directly opposite to the pressure relief mechanism 222. The second groove 254 penetrates the support member 25 along its thickness direction. In a plane perpendicular to the thickness direction of the support member 25, the orthographic projection of the pressure relief mechanism 222 falls completely within the orthographic projection range of the second groove 254.

[0166] The support member 25 has a protrusion 255 on the side facing the bottom wall 221, which forms an airflow channel between the bottom wall 221 and the support member 25. In a plane perpendicular to the thickness direction of the support member 25, the orthographic projection of the protrusion 255 is offset from the pressure relief mechanism 222.

[0167] The support member 25 includes a metal layer 251 and an insulating coating 252 covering the outer surface of the metal layer 251. The insulating coating comprises a ceramic material and a fluorocarbon polymer. The ceramic material includes one or more of alumina (Al2O3), zirconium oxide (ZrO2), silicon nitride (Si3N4), and silicon carbide (SiC); the fluorocarbon polymer includes one or more of polytetrafluoroethylene (PTFE), fluorinated ethylene propylene copolymer (FEP), and fluororubber. The thickness T1 of the insulating coating satisfies: 2μm ≤ T1 ≤ 8μm.

[0168] The metal layer 251 is made of aluminum, aluminum alloy, or steel. The first insulating element 241 and the second insulating element 242 are made of polypropylene (PP), polyethylene terephthalate (PET), or polyimide (PI).

[0169] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that, include: Electrode assembly; The housing has a receiving cavity for accommodating the electrode assembly; A base plate is located between the electrode assembly and the inner wall of the housing and is used to support the electrode assembly; The base plate includes a support member, which includes a metal layer and an insulating coating covering the outer surface of the metal layer.

2. The battery cell according to claim 1, characterized in that, The base plate also includes: The first insulating element is located on the side surface of the support member facing the electrode assembly, and The second insulating element is located on the side surface of the support member facing away from the electrode assembly; The first insulating member and the second insulating member are connected along the outer periphery of the support member so as to completely cover the support member between the first insulating member and the second insulating member.

3. The battery cell according to claim 2, characterized in that, The support member has at least one first groove extending through the support member along its thickness direction, and the first insulating member and the second insulating member are connected at the position of the first groove to form a first connecting part.

4. The battery cell according to claim 3, characterized in that, The first connecting portion is provided with at least one through hole that penetrates the first insulating member and the second insulating member along the thickness direction of the base plate.

5. The battery cell according to any one of claims 1-4, characterized in that, The housing has an opening in its receiving cavity, and the housing includes a bottom wall facing the opening; the battery cell also includes a pressure relief mechanism disposed on the bottom wall, and the bottom support plate is located between the bottom wall and the electrode assembly; The support member is provided with a second groove that is directly opposite the pressure relief mechanism, and the second groove penetrates the support member along the thickness direction of the support member.

6. The battery cell according to claim 5, characterized in that, In a plane perpendicular to the thickness direction of the support member, the orthographic projection of the pressure relief mechanism falls entirely within the orthographic projection range of the second groove.

7. The battery cell according to claim 6, characterized in that, The support member has a protrusion on the side facing the bottom wall, and the protrusion is used to form an airflow channel between the bottom wall and the support member.

8. The battery cell according to claim 7, characterized in that, In a plane perpendicular to the thickness direction of the support member, the orthographic projection of the protrusion is offset from that of the pressure relief mechanism.

9. The battery cell according to any one of claims 1-8, characterized in that, The insulating coating comprises ceramic materials and / or fluorocarbon polymers; The ceramic material includes one or more of alumina, zirconium oxide, silicon nitride, and silicon carbide; The fluorocarbon polymer includes one or more of polytetrafluoroethylene, fluorinated ethylene propylene copolymer, and fluororubber.

10. The battery cell according to any one of claims 1-9, characterized in that, The thickness T1 of the insulating coating satisfies: 2μm≤T1≤8μm.

11. The battery cell according to any one of claims 1-10, characterized in that, The metal layer includes aluminum, aluminum alloy, or steel.

12. The battery cell according to any one of claims 1-11, characterized in that, The thickness T2 of the metal layer satisfies: 0.1mm≤T2≤5mm.

13. The battery cell according to any one of claims 2-4, characterized in that, The melting point of the support member is higher than the melting point of the first insulating member and the melting point of the second insulating member.

14. The battery cell according to any one of claims 2-4, characterized in that, The first insulating element and the second insulating element respectively comprise one or more of polypropylene, polyethylene terephthalate, and polyimide.

15. The battery cell according to any one of claims 2-4, characterized in that, The thickness T3 of the first insulating component satisfies: 0.1mm≤T3≤2mm, and / or the thickness T4 of the second insulating component satisfies: 0.1mm≤T4≤2mm.

16. The battery cell according to any one of claims 1-15, characterized in that, The capacity of the battery cell is greater than or equal to 360Ah.

17. A battery device, characterized in that, Includes the battery cell as described in any one of claims 1-16.

18. An electrical appliance, characterized in that, Includes the battery device as described in claim 17, the battery device being used to provide electrical energy.

19. An energy storage device, characterized in that, It includes a plurality of battery cells as described in any one of claims 1-16 or a plurality of battery devices as described in claim 17, wherein the battery cells or the battery devices are used to store or provide electrical energy.

20. An energy storage system, characterized in that, It includes a power conversion device and an energy storage device as described in claim 19, wherein the power conversion device is used to electrically connect the power generation device and the energy storage device.

21. A charging network, characterized in that, It includes a charging pile and an energy storage device as described in claim 19 or an energy storage system as described in claim 20, wherein the energy storage device or the energy storage system is used to provide electrical energy to the charging pile.

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