Battery device and electric device

Abstract

The application discloses a battery device and an electric device, and belongs to the technical field of batteries. The battery device comprises a box body, a battery monomer and a protective plate. The battery monomer is arranged in the box body. The protective plate is arranged outside the box body. The protective plate comprises multiple metal layers and multiple polyurea layers. The metal layers and the polyurea layers are arranged alternately along the thickness direction of the protective plate. The technical scheme provided by the application can improve the reliability of the battery device.

Description

Technical Field

[0001] This application relates to the field of battery manufacturing, and more specifically, to a battery device and an electrical device. Background Technology

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry, and electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of this sustainable development. For electric vehicles, battery technology is a crucial factor in their development.

[0003] In the development of battery technology, how to improve battery reliability is a technical problem that urgently needs to be solved. Utility Model Content

[0004] This application provides a battery device and an electrical device that can improve the reliability of the battery device during use.

[0005] In a first aspect, embodiments of this application provide a battery device, including a housing, a battery cell, and a protective plate; the battery cell is disposed inside the housing; the protective plate is disposed outside the housing, and the protective plate includes multiple metal layers and multiple polyurea layers, the metal layers and the polyurea layers being alternately disposed along the thickness direction of the protective plate.

[0006] In the above technical solution, the polyurea layer can absorb impact kinetic energy through elastic deformation and convert some of the energy into heat energy through the viscoelastic hysteresis effect. Multiple metal layers and multiple polyurea layers are alternately arranged along the thickness direction of the protective plate. On the one hand, this allows each polyurea layer to sequentially play a buffering role, reducing the risk of single-layer polyurea failure due to excessive deformation. On the other hand, when subjected to a large external impact, the multiple metal layers undergo localized plastic deformation to absorb the impact force. Simultaneously, the multiple metal layers tend to slide relative to their adjacent polyurea layers, further absorbing impact energy through interlayer friction between the metal and polyurea layers. Therefore, compared to a single, thick metal layer, multiple thin metal layers more easily disperse impact force through plastic deformation, avoiding overall brittle fracture. This improves the impact resistance of the protective plate, thereby enhancing the reliability of the battery device when subjected to external impacts.

[0007] In some embodiments, along the thickness direction, the side of the protective plate opposite to the battery cell is the polyurea layer.

[0008] In the above technical solution, the side of the protective plate away from the battery cell is provided with a polyurea layer. On the one hand, this allows the polyurea layer to absorb impact energy through its own elastic deformation, thereby improving the impact resistance of the protective plate and thus improving the reliability of the battery device. On the other hand, it improves the corrosion resistance and wear resistance of the side of the protective plate away from the battery cell, thereby improving the reliability of the battery device.

[0009] In some embodiments, the metal layer is provided with through holes.

[0010] In the above technical solution, by setting through holes in the metal layer, the volume of the metal layer is reduced, thereby reducing the weight of the metal layer, and thus reducing the weight of the protective plate, thereby increasing the energy density of the battery device.

[0011] In some embodiments, the vias on two adjacent metal layers do not overlap along the thickness direction.

[0012] In the above technical solution, the through holes on two adjacent metal layers do not overlap along the thickness direction. Therefore, when the protective plate is punctured by a foreign object, there is at least one metal layer along the thickness direction to restrict the movement of the foreign object in the thickness direction, thereby improving the impact resistance and puncture resistance of the protective plate and thus improving the reliability of the battery device.

[0013] In some embodiments, the protective plate further includes a filling portion that at least partially fills the through-hole, the filling portion being connected to the polyurea layer, and the filling portion being made of the same material as the polyurea layer.

[0014] In the above technical solution, at least some of the through-holes are filled, thereby reducing the risk that foreign objects may directly penetrate the metal layer, causing the metal layer to lose its protective function, and improving the reliability of the protective plate. Simultaneously, the filler portion and the polyurea layer are made of the same material, ensuring that their melting point, thermal conductivity, and other properties are identical. This facilitates the connection of the filler portion and the polyurea layer through integral molding or welding; furthermore, it ensures that the filler portion and the polyurea layer have the same coefficient of thermal expansion, reducing the risk of fracture at the connection point due to accumulated internal stress caused by temperature changes, thus improving the reliability of the protective plate and consequently the reliability of the battery device.

[0015] In some embodiments, two polyurea layers located on opposite sides of the same metal layer are connected by the filler portion.

[0016] In the above technical solution, the two polyurea layers located on both sides of the same metal layer are connected by a filling part, so that the filling part can connect the two polyurea layers on both sides of the same metal layer while filling the through hole. In this way, when there is a risk of peeling between the polyurea layer and the metal layer due to insufficient adhesion at the interface between the polyurea layer and the metal layer, the reliability of the protective plate is improved, thereby improving the reliability of the battery device.

[0017] In some embodiments, the cross-sectional shape of the through hole is circular or elliptical, and the cross-section is perpendicular to the thickness direction.

[0018] In the above technical solution, by making the cross-sectional shape of the through hole circular or elliptical, the risk of stress concentration at the edge of the through hole is reduced, thereby reducing the risk of fatigue fracture of the protective plate due to long-term use, thus improving the fatigue resistance of the protective plate and improving the reliability of the battery device.

[0019] In some embodiments, the radial dimension of the through hole is greater than or equal to 2 mm and less than or equal to 8 mm.

[0020] In the above technical solution, by making the radial dimension of the through hole greater than or equal to 2mm, the volume of the metal layer can be reduced, thereby reducing the weight of the protective plate and thus improving the energy density of the battery device. By making the radial dimension of the through hole less than or equal to 8mm, the risk of foreign objects directly passing through the through hole is reduced, improving the protective plate's ability to resist impacts from foreign objects and enhancing the reliability of the battery device. Therefore, when the radial dimension of the through hole is greater than or equal to 2mm and less than or equal to 8mm, the battery device has a high energy density and good reliability.

[0021] In some embodiments, a plurality of through holes are provided on the same metal layer, and the minimum distance between two adjacent through holes on the same metal layer is greater than or equal to 2 mm and less than or equal to 6 mm.

[0022] In the above technical solution, by ensuring that the minimum distance between two adjacent through-holes on the same metal layer is greater than or equal to 2 mm, a certain distance is maintained between the through-holes. This reduces the risk of overlapping stress fields between adjacent through-holes on the same metal layer, leading to high-stress areas and thus reducing the local tensile / compressive strength of the metal layer. Simultaneously, it reduces the risk of adjacent through-holes forming continuous weak paths, thereby reducing the risk of the metal layer fracturing along these weak paths under fatigue. This improves the reliability of the protective plate and consequently, the reliability of the battery device. Conversely, by ensuring that the minimum distance between two adjacent through-holes on the same metal layer is less than or equal to 6 mm, the number of through-holes per unit area is increased, thereby increasing the weight reduction rate per unit area. This effectively reduces the weight of the protective plate, which in turn helps to improve the energy density of the battery device. Therefore, when the minimum distance between two adjacent through-holes on the same metal layer is greater than or equal to 2 mm and less than or equal to 6 mm, the battery device exhibits high energy density and good reliability.

[0023] In some embodiments, the thickness of the polyurea layer is greater than or equal to 0.3 mm and less than or equal to 1 mm.

[0024] In the above technical solution, by setting the thickness of the polyurea layer to be greater than or equal to 0.3 mm, a single polyurea layer has a certain thickness, thereby reducing the risk of failure due to excessive deformation of the single-layer polyurea. By setting the thickness of the polyurea layer to be less than or equal to 1 mm, the number of polyurea layers is increased under the condition of a fixed protective plate thickness, thereby increasing the number of connection surfaces between the metal layer and the polyurea layer, and thus increasing the connection area between the metal layer and the polyurea layer. Therefore, when multiple metal layers deform and tend to slide with adjacent polyurea layers, more impact energy is absorbed through interlayer friction between the metal layer and the polyurea layer, thereby further improving the impact resistance of the protective plate and improving the reliability of the battery device under external impact. Therefore, when the thickness of the polyurea layer is greater than or equal to 0.3 mm and less than or equal to 1 mm, the reliability of the battery device can be improved.

[0025] In some embodiments, the thickness of the metal layer is greater than or equal to 0.2 mm and less than or equal to 0.6 mm.

[0026] In the above technical solution, by setting the thickness of the metal layer to be greater than or equal to 0.2 mm, the single metal layer has a certain thickness, thereby improving the toughness of the metal layer and thus improving the reliability of the battery device. By setting the thickness of the polyurea layer to be less than or equal to 1 mm, the number of metal layers is increased under the condition of a fixed protective plate thickness, thereby increasing the number of connection surfaces between the metal layer and the polyurea layer, and thus increasing the connection area between the metal layer and the polyurea layer. Therefore, when multiple metal layers deform and tend to slide with adjacent polyurea layers, more impact energy is absorbed through the interlayer friction between the metal layer and the polyurea layer, thereby further improving the impact resistance of the protective plate. Therefore, when the thickness of the metal layer is greater than or equal to 0.2 mm and less than or equal to 1 mm, the reliability of the battery device can be improved.

[0027] In some embodiments, the protective plate is disposed at the bottom of the housing along the direction of gravity.

[0028] In the above technical solution, the protective plate is set at the bottom of the box along the direction of gravity to reduce the risk of damage to the bottom wall of the box, improve the impact resistance of the bottom wall, improve the reliability of the box, and improve the reliability of the battery.

[0029] Secondly, embodiments of this application provide an electrical device, including the battery device provided in any embodiment of the first aspect, wherein the battery device is used to provide electrical energy.

[0030] In the above technical solutions, the battery device provided in any embodiment of the first aspect has high reliability, so that the electrical device powered by the battery device has high reliability. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This application provides structural schematic diagrams of vehicles for some embodiments;

[0033] Figure 2 Exploded views of the structure of the battery device provided in some embodiments of this application;

[0034] Figure 3 Exploded views of the structure of a single battery cell provided in some embodiments of this application;

[0035] Figure 4 Exploded views of the structure of the protective plate provided in some embodiments of this application;

[0036] Figure 5 A cross-sectional view of a protective plate provided for some embodiments of this application;

[0037] Figure 6 This is a schematic diagram of the structure of another protective plate provided in some embodiments of this application;

[0038] Figure 7 A cross-sectional view of another protective plate provided for some embodiments of this application.

[0039] Icons: 1000 - Vehicle; 100 - Battery unit; 10 - Box body; 11 - First box body; 12 - Second box body; 121 - Bottom wall; 20 - Battery cell; 21 - End cap; 22 - Shell; 23 - Electrode assembly; 30 - Protective plate; 31 - Polyurea layer; 31A - First end polyurea layer; 31B - Second end polyurea layer; 32 - Metal layer; 321 - Through hole; 32A - First end metal layer; 32B - Second end metal layer; 33 - Filling part; 200 - Controller; 300 - Motor; X - First direction; Y - Second direction; Z - Gravity direction. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0041] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application 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 description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0042] In this application, the reference to "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 in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0043] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0044] 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, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0045] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0046] In this application, "multiple" means two or more (including two).

[0047] 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.

[0048] Battery cells include, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0049] In related technologies, a battery cell generally includes a casing and an electrode assembly. The casing may include a housing and an end cap. The housing has an opening. After the electrode assembly is installed inside the housing, the opening of the housing can be closed by the end cap to form a sealed space inside the housing to accommodate the electrode assembly.

[0050] The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, placed between the positive and negative electrodes, reduces the risk of short circuits while allowing active ions to pass through.

[0051] In some implementations, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0052] In some implementations, the electrode assembly is a stacked structure.

[0053] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0054] In some embodiments, the electrode assembly is provided with tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0055] The housing is used to encapsulate electrode components and electrolytes. The housing can be made of steel, aluminum, plastic (such as polypropylene), composite metal (such as copper-aluminum composite), or aluminum-plastic film, etc.

[0056] As an example, a battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries.

[0057] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells connected in series, parallel, or mixed connections via a busbar.

[0058] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form a single module. As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0059] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cells housed within the housing.

[0060] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be housed in the housing by fixing the battery module in the housing.

[0061] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0062] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0063] In some embodiments, the battery device may be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0064] The following discussion will primarily focus on rectangular battery cells. It should be understood that the embodiments described below are also applicable in some respects to cylindrical battery cells, pouch cell cells, or blade cell cells.

[0065] The development of battery technology must take into account multiple design factors, such as energy density, cycle life, discharge capacity, charge-discharge rate and other performance parameters. In addition, battery reliability also needs to be considered.

[0066] Battery devices typically house individual battery cells within a casing and are mounted on electrical equipment to provide power. During use, the battery may come into contact with or collide with external objects (such as foreign objects on the road or components on the electrical equipment), potentially damaging the casing. This can lead to risks such as damage to electrical components (e.g., individual battery cells, components within the high-voltage box), short circuits between the positive and negative terminals, affecting the battery's normal operation and ultimately its reliability.

[0067] Based on the above considerations, in order to solve the problems of damaged casing affecting the normal use of the battery device and resulting in poor reliability of the battery device, this application provides a battery device including a casing, battery cells, and a protective plate; the battery cells are disposed inside the casing; the protective plate is disposed outside the casing, and the protective plate includes multiple metal layers and multiple polyurea layers, with the metal layers and polyurea layers alternately arranged along the thickness direction of the protective plate.

[0068] In this battery device, the polyurea layer absorbs impact kinetic energy through elastic deformation and converts some of the energy into heat through viscoelastic hysteresis. Multiple metal layers and multiple polyurea layers are alternately arranged along the thickness direction of the protective plate. On the one hand, each polyurea layer can sequentially play a buffering role, reducing the risk of single-layer polyurea failure due to excessive deformation. On the other hand, the multiple metal layers undergo localized plastic deformation when subjected to large external impacts to absorb the impact force. Simultaneously, the multiple metal layers tend to slide relative to adjacent polyurea layers, further absorbing impact energy through interlayer friction between the metal and polyurea layers. Therefore, compared to a single, thick metal layer, multiple thin metal layers more easily disperse impact force through plastic deformation, avoiding overall brittle fracture. This improves the impact resistance of the protective plate, thereby enhancing the reliability of the battery device under external impact.

[0069] The technical solutions described in the embodiments of this application are applicable to battery devices and electrical devices that use battery devices.

[0070] Electrical devices can include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Among them, 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.

[0071] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 is installed inside the vehicle 1000. The battery device 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to supply power to the vehicle 1000; for example, the battery device 100 can serve as the operating power source or general power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 controls the battery device 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during startup, navigation, and driving.

[0072] In some embodiments of this application, the battery device 100 can not only serve as the operating power or power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0073] Please refer to Figure 2 and Figure 3 Please refer to Figure 4 , Figure 2 This is an exploded view of the structure of the battery device 100 provided in some embodiments of this application. Figure 3 This is an exploded view of the structure of a battery cell 20 provided in some embodiments of this application. Figure 4 This is an exploded view of the structure of the protective plate 30 provided in some embodiments of this application. Embodiments of this application provide a battery device 100, including a housing 10, a battery cell 20, and a protective plate 30; the battery cell 20 is disposed inside the housing 10; the protective plate 30 is disposed outside the housing 10, and the protective plate 30 includes multiple metal layers 32 and multiple polyurea layers 31, with the metal layers 32 and polyurea layers 31 alternately arranged along the thickness direction of the protective plate 30.

[0074] In some embodiments, the housing 10 includes a first housing body 11 and a second housing body 12, which are fitted together to form the housing 10. The first housing body 11 and the second housing body 12 together define an assembly space for accommodating the battery cell 20.

[0075] Optionally, the first box body 11 can be a hollow structure with a second opening at one end, and the second box body 12 can be a plate-like structure. The second box body 12 covers the second opening of the first box body 11 so that the first box body 11 and the second box body 12 together define the assembly space. Alternatively, the first box body 11 and the second box body 12 can both be hollow structures with one side open, and the open side of the second box body 12 covers the second opening of the first box body 11.

[0076] Of course, the box 10 formed by the first box body 11 and the second box body 12 can be of various shapes, such as a cylinder or a cuboid. For example, in... Figure 2 In the middle, box 10 has a rectangular structure.

[0077] The battery cell 20 generally includes a housing and an electrode assembly 23. The housing may include a casing 22 and an end cap 21. The casing 22 has an opening. After the electrode assembly 23 is installed in the casing 22, the opening of the casing 22 can be closed by the end cap 21 to form a sealed space inside the casing to accommodate the electrode assembly 23.

[0078] To meet different power demands, the battery device 100 may include multiple battery cells 20, which can be connected in series, parallel, or a combination thereof. The battery device 100 may also be referred to as a battery pack. Optionally, the multiple battery cells 20 may first be connected in series, parallel, or a combination thereof to form a battery cell assembly, and then the battery cell assemblies may be connected in series, parallel, or a combination thereof to form the battery device 100. In other words, the multiple battery cells 20 can directly form the battery device 100, or they can first be assembled into battery cell assemblies, and then the battery cell assemblies can be assembled into the battery device 100.

[0079] Depending on different power demands, the number of battery cells 20 in a battery cell assembly can be set to any value. Multiple battery cells 20 can be connected in series, parallel, or mixed connections to achieve a larger capacity or power. Since each battery device 100 may include a large number of battery cells 20, for ease of installation, the battery cells 20 can be grouped, with each group of battery cells 20 forming a battery cell assembly. The number of battery cells 20 included in a battery cell assembly is unlimited and can be set according to requirements. The battery device 100 may include multiple battery cell assemblies, which can be connected in series, parallel, or mixed connections.

[0080] The protective plate 30 is a plate-shaped structure in the battery device 100 used to absorb external impact forces.

[0081] "The protective plate 30 is disposed outside the box 10" can be understood as the protective plate 30 being located outside at least one side of the box 10. For example, the protective plate 30 can be a plate-shaped part covering one side of the box 10; or, the protective plate 30 can be multiple plate-shaped structures covering multiple sides of the box 10 and whose edges are connected to each other.

[0082] The metal layer 32 is made of metal; for example, it may be made of copper, iron, aluminum, or other materials, in some embodiments. The metal layer 32 may also be made of an alloy; for example, it may be made of an aluminum alloy.

[0083] Polyurea layer 31 is made of polyurea, a high-performance polymer material that is an elastomer formed by a rapid chemical reaction between isocyanate component (component A) and amino compound component (component B).

[0084] The polyurea layer 31 is less affected by ambient temperature and humidity, has a lower risk of generating volatile substances after spraying, and exhibits good tensile strength, elongation, flexibility, abrasion resistance, aging resistance, corrosion resistance, and thermal stability.

[0085] Please refer to Figure 4The statement that “the protective plate 30 includes multiple metal layers 32 and multiple polyurea layers 31” means that the metal layers 32 have at least two layers and the polyurea layers 31 have at least two layers.

[0086] "The metal layer 32 and the polyurea layer 31 are alternately arranged along the thickness direction of the protective plate 30" means that the polyurea layer 31 and the metal layer 32 are stacked alternately to form the protective plate 30.

[0087] In some embodiments, the polyurea layer 31 may be adhesively disposed on at least a portion of at least one side of the metal layer 32 in the thickness direction.

[0088] In some embodiments, the polyurea layer 31 can be applied by spraying onto at least a portion of at least one side of the metal layer 32 in the thickness direction.

[0089] In some embodiments, the polyurea layer 31 may be completely coated on at least a portion of at least one side of the metal layer 32 in the thickness direction.

[0090] The polyurea layer 31 can be cured without a catalyst and is easy to spray onto curved, inclined and vertical surfaces, and is easy to spray onto at least one side of the metal layer 32 in the thickness direction.

[0091] For example, the polyurea layer 31 may be located on the side of the metal layer 32 closer to the housing 10; or it may be located on the side of the metal layer 32 away from the housing 10; or it may be located on opposite sides of the metal layer 32.

[0092] In this embodiment, the polyurea layer 31 can absorb impact kinetic energy through elastic deformation and convert some of the energy into heat energy through viscoelastic hysteresis. The multilayer metal layer 32 and the multilayer polyurea layer 31 are alternately arranged along the thickness direction of the protective plate 30. On the one hand, this allows each polyurea layer 31 to sequentially play a buffering role, reducing the risk of single-layer polyurea failure due to excessive deformation. On the other hand, the multilayer metal layer 32 undergoes localized plastic deformation when subjected to a large external impact to absorb the impact force. Simultaneously, the multilayer metal layer 32 tends to slide relative to its adjacent polyurea layer 31, thereby further absorbing impact energy through interlayer friction between the metal layer 32 and the polyurea layer 31. Therefore, compared to a single-layer metal layer 32 with a larger thickness, the multilayer thin metal layer more easily disperses the impact force through plastic deformation, avoiding overall brittle fracture. This improves the impact resistance of the protective plate 30, thereby enhancing the reliability of the battery device 100 when subjected to external impacts.

[0093] According to some embodiments of this application, please refer to Figure 4 and Figure 5 , Figure 5This is a cross-sectional view of a protective plate 30 provided for some embodiments of this application. Along the thickness direction, the side of the protective plate 30 facing away from the battery cell 20 is a polyurea layer 31.

[0094] In some embodiments, the polyurea layer 31 in the multilayer polyurea layer 31 that is furthest from the battery cell 20 in the thickness direction is the first end polyurea layer 31A, and the metal layer 32 in the multilayer metal layer 32 that is furthest from the battery cell 20 in the thickness direction is the first end metal layer 32A. The first end polyurea layer 31A is located on the side of the first end metal layer 32A that is furthest from the battery cell 20, and the surface of the first end polyurea layer 31A that is furthest from the battery cell 20 is the outer surface of the protective plate 30.

[0095] In some embodiments, the polyurea layer 31 of the multilayer polyurea layers 31 that is closest to the battery cell 20 in the thickness direction is the second-end polyurea layer 31B, and the metal layer 32 of the multilayer metal layers 32 that is closest to the battery cell 20 in the thickness direction is the second-end metal layer 32B. The second-end polyurea layer 31B is located on the side of the second-end metal layer 32B closest to the battery cell 20, and the surface of the second-end polyurea layer 31B closest to the battery cell 20 is the inner surface of the protective plate 30. This increases the connection area between the metal layer 32 and the polyurea layer 31, so that when the multilayer metal layer 32 deforms and has a tendency to slide with the adjacent polyurea layer 31, more impact energy is further absorbed through the interlayer friction between the metal layer 32 and the polyurea layer 31, thereby further improving the impact resistance of the protective plate 30.

[0096] In some embodiments, the polyurea layer 31 closest to the battery cell 20 in the thickness direction among the multilayer polyurea layers 31 is the second-end polyurea layer 31B, and the metal layer 32 closest to the battery cell 20 in the thickness direction among the multilayer metal layers 32 is the second-end metal layer 32B. The second-end metal layer 32B is located on the side of the second-end polyurea layer 31B closest to the battery cell 20, and the surface of the second-end metal layer 32B closest to the battery cell 20 is the inner surface of the protective plate 30. This facilitates the connection of the housing 10 and the metal layers 32 by welding.

[0097] In this embodiment, the side of the protective plate 30 facing away from the battery cell 20 is provided with a polyurea layer 31. On the one hand, this allows the polyurea layer 31 to absorb impact energy through its own elastic deformation, thereby improving the impact resistance of the protective plate 30 and thus improving the reliability of the battery device 100. On the other hand, it improves the corrosion resistance and wear resistance of the side of the protective plate 30 facing away from the battery cell 20, thereby improving the reliability of the battery device 100.

[0098] Please refer to Figure 6 , Figure 6This is a schematic diagram of another protective plate 30 provided in some embodiments of this application. According to some embodiments of this application, a through hole 321 is provided on the metal layer 32.

[0099] "The metal layer 32 is provided with a through hole 321" means that the metal layer 32 is provided with a through hole 321 connecting the two sides of the metal layer 32 in the thickness direction. For example, the through hole 321 penetrates the metal layer 32 in the thickness direction.

[0100] Understandably, the cross-section of the through hole 321 can be of any shape; for example, the cross-section of the through hole 321 can be a polygon.

[0101] In this embodiment, by providing through holes 321 on the metal layer 32, the volume of the metal layer 32 is reduced, thereby reducing the weight of the metal layer 32 and the weight of the protective plate 30, thereby increasing the energy density of the battery device 100.

[0102] Please refer to Figure 6 According to some embodiments of this application, the vias 321 on two adjacent metal layers 32 do not overlap along the thickness direction.

[0103] For the purpose of specifying the extent of the vias 321 on the two adjacent metal layers 32, please refer to [reference needed]. Figure 6 The area of ​​the via 321 on the adjacent metal layer 32 is marked by dashed lines in the figure. It should be noted that the dashed lines are only for the purpose of showing the via 321 on the adjacent metal layer 32 and do not represent any physical meaning.

[0104] In this embodiment, the through holes 321 on two adjacent metal layers 32 do not overlap along the thickness direction, so that when the protective plate 30 is punctured by a foreign object, there is at least one metal layer 32 along the thickness direction to restrict the movement of the foreign object in the thickness direction, thereby improving the impact resistance and puncture resistance of the protective plate 30, and thus improving the reliability of the battery device 100.

[0105] Please refer to Figure 7 , Figure 7 This is a cross-sectional view of another protective plate 30 provided in some embodiments of this application. According to some embodiments of this application, the protective plate 30 further includes a filling portion 33 that at least partially fills the through hole 321, the filling portion 33 being connected to the polyurea layer 31, and the filling portion 33 being made of the same material as the polyurea layer 31.

[0106] "The filling part 33 at least partially fills the through hole 321" means that the filling part 33 fills the through hole 321, or the filling part 33 completely fills the through hole 321.

[0107] The fact that the filler part 33 is made of the same material as the polyurea layer 31 means that the filler part 33 is also made of polyurea.

[0108] In embodiments where the polyurea layer 31 is formed by coating or spraying onto the metal layer 32, the filler portion 33 is made of the same material as the polyurea layer 31. This facilitates the formation of the filler portion 33 simultaneously with the formation of the polyurea layer 31 through coating or spraying, thereby simplifying the manufacturing process of the protective plate 30 and making the production of the protective plate 30 easier.

[0109] In this embodiment, at least part of the through-hole 321 is filled, thereby reducing the risk that foreign objects may pass directly through the metal layer 32, causing the metal layer 32 to lose its protective function, and improving the reliability of the protective plate 30. Simultaneously, the filling portion 33 and the polyurea layer 31 are made of the same material, ensuring that the filling portion 33 and the polyurea layer 31 have the same melting point, thermal conductivity, and other properties. On the one hand, this facilitates the connection of the filling portion 33 and the polyurea layer 31 through integral molding or welding; on the other hand, it ensures that the filling portion 33 and the polyurea layer 31 have the same coefficient of thermal expansion, reducing the risk of fracture at the connection between the filling portion 33 and the polyurea layer 31 due to accumulated internal stress caused by temperature changes, thus improving the reliability of the protective plate 30 and consequently the reliability of the battery device 100.

[0110] Please refer to Figure 7 According to some embodiments of this application, two polyurea layers 31 located on both sides of the same metal layer 32 are connected by a filling portion 33.

[0111] In this embodiment, the two polyurea layers 31 located on both sides of the same metal layer 32 are connected by a filling portion 33. This allows the filling portion 33 to fill the through hole 321 while connecting the two polyurea layers 31 on both sides of the same metal layer 32. This improves the reliability of the protective plate 30 and, consequently, the reliability of the battery device 100 when there is a risk of interlayer peeling between the polyurea layer 31 and the metal layer 32 due to insufficient adhesion at the interface.

[0112] Please refer to Figure 7 According to some embodiments of this application, the cross-sectional shape of the through hole 321 is circular or elliptical, and the cross-section is perpendicular to the thickness direction.

[0113] In this embodiment, by making the cross-sectional shape of the through hole 321 circular or elliptical, the risk of stress concentration at the edge of the through hole 321 is reduced, thereby reducing the risk of fatigue fracture of the protective plate 30 due to long-term use, thus improving the fatigue resistance of the protective plate 30, and further improving the reliability of the battery device 100.

[0114] Please refer to Figure 6 According to some embodiments of this application, the radial dimension of the through hole 321 is greater than or equal to 2 mm and less than or equal to 8 mm.

[0115] In some embodiments, the radial dimension of the through hole 321 is L1, which satisfies 2mm≤L1≤8mm.

[0116] L1 is the radial dimension of the through hole 321. In an embodiment where the cross-section of the through hole 321 is circular, L1 is the diameter of the cross-section. In an embodiment where the cross-section of the through hole 321 is elliptical, L1 is the major axis of the cross-section.

[0117] For example, L1 can be 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, etc.

[0118] In this embodiment, by making the radial dimension of the through hole 321 greater than or equal to 2 mm, the volume of the metal layer 32 can be reduced, thereby reducing the weight of the protective plate 30 and thus improving the energy density of the battery device 100. By making the radial dimension of the through hole 321 less than or equal to 8 mm, the risk of foreign objects directly passing through the through hole 321 is reduced, improving the protective plate 30's ability to protect against impacts from foreign objects and enhancing the reliability of the battery device 100. Therefore, when the radial dimension of the through hole 321 is greater than or equal to 2 mm and less than or equal to 8 mm, the battery device 100 has a high energy density and good reliability.

[0119] Please refer to Figure 6 According to some embodiments of this application, a plurality of through holes 321 are provided on the same metal layer 32, and the minimum distance between two adjacent through holes 321 on the same metal layer 32 is greater than or equal to 2 mm and less than or equal to 6 mm.

[0120] In some embodiments, the plurality of through holes 321 on the same metal layer 32 are arranged in multiple rows along the first direction X, and each row of through holes 321 consists of a plurality of through holes spaced apart along the second direction Y. Exemplarily, corresponding through holes 321 in two adjacent rows may overlap along the first direction X, or they may not overlap along the first direction X. The first direction X and the second direction Y are two directions perpendicular to each other of the thickness direction.

[0121] In some embodiments, the minimum distance between two adjacent vias 321 on the same metal layer 32 is L2, which satisfies 2mm≤L2≤6mm.

[0122] The method for measuring L2 is as follows: The projections of the axes of two adjacent through holes 321 on the same metal layer 32 onto one side of the thickness direction of the metal layer 32 are the first point and the second point, respectively. The first point and the second point are connected to form a first line. The length of the part of the first line outside the two adjacent through holes 321 on the same metal layer 32 is L2.

[0123] For example, L2 can be 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, etc.

[0124] In this embodiment, by ensuring that the minimum distance between two adjacent through holes 321 on the same metal layer 32 is greater than or equal to 2 mm, a certain distance is maintained between the through holes 321. This reduces the risk of overlapping stress fields between adjacent through holes 321 on the same metal layer 32, which could lead to high stress areas and reduce the local tensile / compressive strength of the metal layer 32. Simultaneously, it reduces the risk of adjacent through holes 321 forming continuous weak paths, thereby reducing the risk of the metal layer 32 fracturing along these weak paths under fatigue. This improves the reliability of the protective plate 30 and consequently, the reliability of the battery device 100. Conversely, by ensuring that the minimum distance between two adjacent through holes 321 on the same metal layer 32 is less than or equal to 6 mm, the number of through holes 321 per unit area is increased, thereby increasing the weight reduction rate per unit area. This effectively reduces the weight of the protective plate 30, which in turn helps to improve the energy density of the battery device 100. Therefore, when the minimum distance between two adjacent through holes 321 on the same metal layer 32 is greater than or equal to 2 mm and less than or equal to 6 mm, the battery device 100 possesses high energy density and good reliability.

[0125] Please refer to Figure 7 According to some embodiments of this application, the thickness of the polyurea layer 31 is greater than or equal to 0.3 mm and less than or equal to 1 mm.

[0126] In some embodiments, the thickness of the polyurea layer 31 is H1, satisfying 0.3mm≤H1≤1mm.

[0127] For example, H1 can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc.

[0128] In this embodiment, by setting the thickness of the polyurea layer 31 to be greater than or equal to 0.3 mm, a single layer of polyurea 31 is made to have a certain thickness, thereby reducing the risk of failure of a single layer of polyurea due to excessive deformation. By setting the thickness of the polyurea layer 31 to be less than or equal to 1 mm, the number of polyurea layers 31 is increased while the thickness of the protective plate 30 is constant, thereby increasing the number of connection surfaces between the metal layer 32 and the polyurea layer 31, and thus increasing the connection area between the metal layer 32 and the polyurea layer 31. When multiple metal layers 32 deform and tend to slide with adjacent polyurea layers 31, more impact energy is absorbed through interlayer friction between the metal layer 32 and the polyurea layer 31, thereby further improving the impact resistance of the protective plate 30 and improving the reliability of the battery device 100 when subjected to external impact. Therefore, when the thickness of the polyurea layer 31 is greater than or equal to 0.3 mm and less than or equal to 1 mm, the reliability of the battery device 100 can be improved.

[0129] Please refer to Figure 7 According to some embodiments of this application, the thickness of the metal layer 32 is greater than or equal to 0.2 mm and less than or equal to 0.6 mm.

[0130] In some embodiments, the thickness of the polyurea layer 31 is H2, satisfying 0.2mm≤H2≤0.6mm.

[0131] For example, H2 can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, etc.

[0132] In this embodiment, by setting the thickness of the metal layer 32 to be greater than or equal to 0.2 mm, the single-layer metal layer 32 has a certain thickness, thereby improving the toughness of the metal layer 32 and thus improving the reliability of the battery device 100. By setting the thickness of the polyurea layer 31 to be less than or equal to 1 mm, the number of metal layers 32 is increased while the thickness of the protective plate 30 is constant, thereby increasing the number of connection surfaces between the metal layer 32 and the polyurea layer 31, and thus increasing the connection area between the metal layer 32 and the polyurea layer 31. Therefore, when the multiple metal layers 32 deform and tend to slide with the adjacent polyurea layers 31, more impact energy is absorbed through the interlayer friction between the metal layer 32 and the polyurea layer 31, thereby further improving the impact resistance of the protective plate 30. Therefore, when the thickness of the metal layer 32 is greater than or equal to 0.2 mm and less than or equal to 1 mm, the reliability of the battery device 100 can be improved.

[0133] Please refer to Figure 2 According to some embodiments of this application, the protective plate 30 is disposed at the bottom of the box 10 along the gravity direction Z.

[0134] Understandably, the direction of gravity Z is parallel to the thickness direction.

[0135] In this embodiment, the protective plate 30 is disposed at the bottom of the housing 10 along the gravity direction Z to reduce the risk of damage to the bottom wall 121 of the housing 10, improve the impact resistance of the bottom wall 121, improve the reliability of the housing 10, and improve the reliability of the battery.

[0136] According to some embodiments of this application, this application also provides an electrical device, which includes a battery device 100 of any of the above schemes, and the battery device 100 is used to provide electrical energy to the electrical device.

[0137] According to some embodiments of this application, refer to Figures 2 to 7 This application provides a battery device 100, including a housing 10, a battery cell 20, and a protective plate 30. The battery cell 20 is disposed inside the housing 10. The protective plate 30 is disposed at the bottom of the housing 10 along the gravity direction Z. The protective plate 30 includes multiple metal layers 32 and multiple polyurea layers 31, which are alternately arranged along the thickness direction of the protective plate 30. Along the thickness direction, the side of the protective plate 30 opposite to the battery cell 20 is the polyurea layer 31. Through holes 321 are provided on the metal layers 32. Along the thickness direction, the through holes 321 on adjacent metal layers 32 do not overlap. The protective plate 30 also includes a filling portion 33 that at least partially fills the through holes 321. The filling portion 33 is connected to the polyurea layer 31, and the filling portion 33 and the polyurea layer 31 are made of the same material. Two polyurea layers 31 located on both sides of the same metal layer 32 are connected by the filling portion 33. The cross-sectional shape of the hole is circular or elliptical, and the cross-section is perpendicular to the thickness direction. The radial dimension of the through-hole 321 is greater than or equal to 2 mm and less than or equal to 8 mm. Multiple through-holes 321 are provided on the same metal layer 32, and the minimum distance between two adjacent through-holes 321 on the same metal layer 32 is greater than or equal to 2 mm and less than or equal to 6 mm. The thickness of the polyurea layer 31 is greater than or equal to 0.3 mm and less than or equal to 1 mm. The thickness of the metal layer 32 is greater than or equal to 0.2 mm and less than or equal to 0.6 mm.

[0138] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0139] The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit this application. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery device, characterized in that, include: Box; The battery cell is housed within the casing. A protective panel is disposed on the outside of the enclosure. The protective panel includes multiple metal layers and multiple polyurea layers, with the metal layers and polyurea layers alternately arranged along the thickness direction of the protective panel.

2. The battery device as claimed in claim 1, characterized in that, Along the thickness direction, the side of the protective plate opposite to the battery cell is the polyurea layer.

3. The battery device as claimed in claim 1, characterized in that, The metal layer has through holes.

4. The battery device as claimed in claim 3, characterized in that, Along the thickness direction, the vias on two adjacent metal layers do not overlap.

5. The battery device as claimed in claim 3, characterized in that, The protective plate also includes: A filling portion, at least partially filling the through-hole, the filling portion being connected to the polyurea layer, and the filling portion being made of the same material as the polyurea layer.

6. The battery device as claimed in claim 5, characterized in that, The two polyurea layers located on opposite sides of the same metal layer are connected by the filling portion.

7. The battery device as claimed in claim 3, characterized in that, The cross-sectional shape of the through hole is circular or elliptical, and the cross-section is perpendicular to the thickness direction.

8. The battery device as claimed in claim 7, characterized in that, The radial dimension of the through hole is greater than or equal to 2 mm and less than or equal to 8 mm.

9. The battery device as claimed in claim 3, characterized in that, Multiple through holes are provided on the same metal layer, and the minimum distance between two adjacent through holes on the same metal layer is greater than or equal to 2 mm and less than or equal to 6 mm.

10. The battery device as claimed in claim 1, characterized in that, The thickness of the polyurea layer is greater than or equal to 0.3 mm and less than or equal to 1 mm.

11. The battery device as claimed in claim 1, characterized in that, The thickness of the metal layer is greater than or equal to 0.2 mm and less than or equal to 0.6 mm.

12. The battery device as claimed in claim 1, characterized in that, Along the direction of gravity, the protective plate is located at the bottom of the box.

13. An electrical appliance, characterized in that, The device includes a battery device as described in any one of claims 1-12, the battery device being used to provide electrical energy to the electrical device.

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