Battery and electrical device

Abstract

A battery (100) and an electrical device. The battery (100) comprises a heat exchange member (10) and a plurality of battery cells (101). The battery cells (101) each comprise a casing, the casing has a first surface in contact with or opposite to the heat exchange member (10) and a second surface not in contact with or opposite to the heat exchange member (10), a heat conducting coating (102) is provided on the first surface, a heat insulating coating (103) is provided on the second surface, and the heat conducting coating (102) and the heat insulating coating (103) are both insulating layers. The present application aims to improve the insulation reliability of the case of the battery (100) and reduce the impact on the heat exchange effect of the battery (100).

Description

Batteries and electrical devices

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on February 21, 2024, with application number 202420322871.4 and application name “Battery and Electrical Device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application belongs to the field of battery technology, and in particular relates to a battery and an electrical device. Background Art

[0003] Battery casings are usually designed to be charged to prevent ions from embedding into the battery casing and causing electrochemical corrosion, which in turn causes electrolyte leakage and insulation failure. Since most battery casings are charged, in order to ensure the safety of the battery system, the battery casing needs to be insulated to prevent electrochemical corrosion of the battery casing.

[0004] The existing insulation method is to use a film to cover the battery shell. The film has defects such as easy generation of bubbles and wrinkles, which reduces the insulation reliability. In addition, the film covering the shell surface also has an adverse effect on the heat exchange effect of the battery shell.

[0005] Summary of the Invention

[0006] In view of the above problems, the present application provides a battery and an electrical device, which aim to improve the insulation reliability of the battery housing and the insulation setting can reduce the impact on the heat exchange effect of the battery. Technical Solutions

[0007] To solve the above problems, in a first aspect, the present application provides a battery comprising a heat exchange element and a plurality of battery cells, wherein the battery cells comprise a shell, the shell having a first surface in contact with or opposite to the heat exchange element and a second surface not in contact with or opposite to the heat exchange element, a thermally conductive coating being provided on the first surface, and a thermally insulating coating being provided on the second surface, wherein both the thermally conductive coating and the thermally insulating coating are insulating layers. A thermally conductive coating is provided on the first surface of the shell that is in contact with or opposite to the heat exchange element to achieve good heat exchange, and a thermally insulating coating is provided on the second surface that is not in contact with or opposite to the heat exchange element to protect the non-heat exchange surface. At the same time, both the thermally conductive coating and the thermally insulating coating are insulating layers, thereby ensuring an insulating effect.

[0008] In one embodiment of the first aspect, the second surface of the housing includes a surface facing or in contact with the housing of an adjacent battery cell. After the second surface is provided with a thermal insulation coating, mutual interference between adjacent battery cells due to thermal runaway can be prevented.

[0009] In an embodiment of the first aspect, the second surface of the housing includes a surface that is not opposite to or in contact with the housing of an adjacent battery cell, thereby achieving comprehensive protection of all surfaces of the battery cell.

[0010] In one embodiment of the first aspect, the first surface comprises the bottom surface of the battery cell, and the heat exchange element is positioned directly opposite the bottom surface. The first surface can be the bottom surface of a battery cell, and the heat exchange element can also be positioned to contact the bottom surfaces of multiple battery cells simultaneously, facilitating placement of the heat exchange element. Furthermore, for commonly used electrical devices, placing the heat exchange element at a relatively low vertical position on the bottom surface provides a more rational structure and facilitates assembly.

[0011] In one embodiment of the first aspect, the first surface comprises the top surface of the battery cell, and the heat exchange element is positioned directly opposite the top surface. The heat exchange element is positioned according to specific usage requirements to achieve optimal structural assembly of the battery, achieving good heat dissipation without affecting the operation of the explosion-proof valve. Furthermore, the top surface can also allow a single heat exchange element to simultaneously contact the top surfaces of multiple battery cells to achieve heat dissipation.

[0012] In one embodiment of the first aspect, the first surface comprises a side surface of the battery cell, and the heat exchange element is disposed opposite the side surface. The heat exchange surface can be selected based on the arrangement of the battery cells within the enclosure and actual needs, i.e., it can be a side surface of the battery cell. When the horizontal space within the enclosure is large but the vertical space is small, the first surface can be a side surface. This facilitates the placement of the heat exchange element and increases space utilization.

[0013] In one embodiment of the first aspect, the first surface comprises a large surface of the battery cell, and the heat exchange element is disposed opposite the large surface. By using the large surface as both the first surface and the heat exchange surface, a larger contact and heat exchange area is provided, thereby achieving a better heat exchange effect.

[0014] In one embodiment of the first aspect, the thermal insulation coating is a layer of heat-resistant material. It can withstand high temperatures and operate continuously without damage, ensuring that adjacent battery cells operate independently without mutual interference. Even if thermal runaway occurs in one battery cell, the impact on adjacent battery cells is reduced.

[0015] In one embodiment of the first aspect, the thermally conductive coating comprises a ceramic-based composite material layer and / or a resin-based composite material layer. This layer has high mechanical strength and is heat-conductive. While ensuring effective heat exchange, it is also protected from damage during thermal runaway of the battery cell, while still maintaining effective insulation of the battery cell housing. This significantly improves the reliability of the battery cell housing insulation. Furthermore, compared to film-coated insulation, the manufacturing process is simpler and faster, and it avoids bubbles that form on the coating surface during the coating process, thereby maintaining the insulation and withstand voltage performance of the battery cell.

[0016] In one embodiment of the first aspect, the thermally conductive coating is a ceramic resin matrix composite material layer, which has the excellent properties of both ceramics and resin.

[0017] In one embodiment of the first aspect, the thermal insulation coating is a ceramic-based composite material coating and / or a resin-based composite material coating. The thermal insulation coating has the above-mentioned effects and can also provide thermal insulation, isolating the heat between adjacent battery cells from each other without mutual interference.

[0018] In one embodiment of the first aspect, the thermal insulation coating is a ceramic resin-based composite material layer. The thermal insulation coating has the above-mentioned two effects and isolates the heat between adjacent battery cells from each other without mutual interference.

[0019] In one embodiment of the first aspect, the thermally conductive coating comprises a layer of boron nitride combined with a water-based epoxy resin. This significantly enhances the coating's mechanical properties, thermal conductivity, and heat resistance. The coating exhibits excellent mechanical properties, high mechanical strength, good thermal conductivity, and stable insulation, maintaining good insulation even when thermal runaway occurs in a battery cell.

[0020] In one embodiment of the first aspect, the thermally conductive coating is an epoxy resin-based thermally conductive insulating coating modified with epoxy polyhedral silsesquioxane. This can enhance the thermal stability of the material, improve mechanical properties, and other physical properties, making the coating less susceptible to cracking and peeling while maintaining stable insulation. This coating can maintain good insulation even when thermal runaway occurs in a battery cell.

[0021] In one embodiment of the first aspect, the thermal insulation coating is a nanocomposite ceramic-based resin insulation layer or a high-temperature resistant ceramic insulation layer. Nanoceramic materials have excellent hardness, fracture toughness, and low-temperature ductility, significantly improving the mechanical properties of the nanocomposite ceramic-based resin, particularly hardness and strength. High-temperature resistant ceramics have excellent high-temperature resistance, corrosion resistance, low thermal conductivity, good thermal stability, and wear resistance.

[0022] In a second aspect, the present application further provides an electrical device, which includes the battery provided in any one of the above embodiments.

[0023] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the embodiments below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference numerals are used throughout the drawings to denote the same components. In the drawings:

[0025] FIG1 is a schematic structural diagram of a vehicle according to some embodiments of the present application;

[0026] FIG2 is a schematic structural diagram of a battery according to some embodiments of the present application;

[0027] FIG3 is a schematic structural diagram of a battery according to some embodiments of the present application;

[0028] FIG4 is a schematic structural diagram of a battery according to some embodiments of the present application;

[0029] FIG5 is a schematic structural diagram of a battery cell according to some embodiments of the present application.

[0030] The reference numerals in the specific implementation manner are as follows: 1000, vehicle; 100, battery; 200, controller; 300, motor; 101, battery cell; 1012, bottom surface; 1013, top surface; 1014, side surface; 1015, large surface; 102, thermal conductive coating; 103, thermal insulation coating; 10, heat exchange component. DETAILED DESCRIPTION

[0031] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0033] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0034] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0035] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0036] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0037] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0038] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0039] Currently, market developments indicate that batteries are increasingly being used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. As battery applications continue to expand, market demand is also growing.

[0040] To meet different power requirements, a battery can include multiple battery cells, where the multiple battery cells can be connected in series, parallel, or in a hybrid connection. Hybrid connection refers to a mixture of series and parallel connections. Optionally, multiple battery cells can first be connected in series, parallel, or in a hybrid connection to form a battery module, and multiple battery modules can then be connected in series, parallel, or in a hybrid connection to form a battery. In other words, multiple battery cells can be directly combined into a battery, or they can first be combined into battery modules, and then the battery modules can be combined into a battery. The battery is further installed in an electrical device to provide power to the device.

[0041] Batteries may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, and are not limited to these in the present application. Batteries may be cylindrical, flat, rectangular, or in other shapes, and are not limited to these in the present application. Batteries are generally categorized into three types based on packaging: cylindrical batteries, prismatic batteries, and pouch batteries.

[0042] The battery casing is usually designed to be charged to prevent lithium ions from embedding into the battery aluminum casing and causing electrochemical corrosion, which in turn causes electrolyte leakage and insulation failure. Since most battery casings are charged, in order to ensure the safety of the battery system, for example, to avoid the positive and negative electrodes of the battery being connected to the battery casing during the battery transportation process or module assembly process, causing a short circuit and explosion, the battery casing needs to be insulated to prevent electrochemical corrosion and short circuit risks.

[0043] Batteries operate normally only within a certain temperature range. Batteries of any shape or connection method will generate heat during use. Excessive heat can adversely affect battery performance and service life. In related technologies, a heat exchange system can be installed to remove heat from the battery. This heat exchange system can be either an air or liquid heat exchange system.

[0044] Liquid heat exchange systems use a heat exchange fluid as a heat exchange medium, utilizing a liquid pump and heat exchange piping to move the fluid through the battery system. These systems are categorized as either direct contact or indirect contact. Direct contact heat exchange involves immersing the battery pack directly in the heat exchange fluid. Indirect contact heat exchange involves arranging heat exchange piping between battery modules or placing heat exchange components within the battery pack. Heat is removed through direct contact between the heat exchange piping and the battery modules, or between the heat exchange components and the batteries within the battery pack, and absorption of heat by the liquid within the piping or components.

[0045] The heat exchange system may include a heat exchange element, the surface of which contacts the surface of the battery. During use, for example, a heat exchange fluid flows through the heat exchange element, removing heat from the battery and cooling it. The heat exchange element has a heat exchange channel within it, through which the heat exchange fluid flows.

[0046] Therefore, based on the above considerations, the surface of the battery housing is required to have good insulation properties, and the insulation setting should not affect the heat dissipation between the battery housing and the heat exchange element.

[0047] In the related art, the external insulation method of the battery shell is often coated with materials such as PET (Polyethylene Terephthalate), PI (Polyimide Film), and PP (Polypropylene) film. As the size of the battery increases, the external coating process of the battery shell is difficult to control, and it is easy to produce defects such as bubbles and wrinkles. These defects will affect the subsequent assembly of the battery in the module or the whole package, as well as the insulation effect of the battery shell. The internal insulation film materials such as PET film and PP film have poor strength and are easily pierced by ultrasonic welding slag and laser welding slag generated during the production of the battery cell. Since the bare battery cell usually adopts the form of the negative electrode enclosing the positive electrode, and the battery shell is fully charged, the welding slag piercing the internal insulation film is very likely to cause internal short circuit and other safety risks.

[0048] While traditional external insulating films made of materials like PET, PI, and PP have certain insulating properties, the laminating process for these films is complex and prone to defects like bubbles and wrinkles, which can affect the coating of structural adhesive and thermal adhesive between cells. During the assembly of batteries into modules, a preload must be applied to constrain cell expansion and increase the battery's cycle life. Structural adhesive must be applied between the large battery surfaces to ensure smooth module assembly, and thermal adhesive must be applied to the bottom of the battery to ensure heat dissipation. The coating effect of traditional PET external insulating films and their compatibility with thermal and structural adhesives significantly impact battery performance.

[0049] Based on the above considerations, an embodiment of the present application provides a battery 100 , in which the housing of the battery cell 101 has good insulation reliability and reduces the impact on the heat exchange effect.

[0050] The battery 100 provided in this embodiment can be applied to an electrical device, i.e., an electrical device that uses the battery 100 as a power source or various energy storage systems that use the battery 100 as an energy storage element. The electrical device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, and the like. The electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, and the like. The spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, and the like.

[0051] The battery 100 disclosed in the embodiment of the present application can be used in, but is not limited to, electrical devices such as vehicles 1000, ships, or aircraft. Electrical devices can use a power supply system equipped with the battery 100 disclosed in this application, which helps improve the reliability of the electrical devices.

[0052] For the convenience of description, the following embodiments are described by taking the electric device provided in the embodiments of the present application as a vehicle 1000 as an example.

[0053] Please refer to Figure 1, which is a schematic structural diagram of a vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 can be provided at the bottom, head or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can serve as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0054] In some embodiments of the present application, the battery 100 can serve not only as an operating power source for the vehicle 1000, but also as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0055] In some embodiments of the present application, the battery 100 may include a housing, a battery cell 101, and a heat exchange system, wherein the battery cell 101 is accommodated in the housing. The housing is used to provide a space for accommodating the battery cell 101, and the housing may adopt various structures.

[0056] The battery cell 101 can be a secondary battery or a primary battery, wherein a secondary battery refers to a battery cell that can be recharged to activate the active material after the battery cell is discharged and continue to be used, and a primary battery refers to a battery cell that cannot be recharged to activate the active material after the battery cell's power is exhausted and continue to be used. The battery cell can also be a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc., but is not limited thereto. The battery cell can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell, or a battery cell of other shapes. Prismatic battery cells include square-shell battery cells, blade-shaped battery cells, and polygonal prismatic batteries. Polygonal prismatic batteries are, for example, hexagonal prismatic batteries, etc. This application has no special restrictions.

[0057] As a specific embodiment of the battery 100 provided in the present application, please refer to Figures 2, 3 and 4. The battery 100 includes a heat exchange element 10 and multiple battery cells 101. The battery cell 101 includes a shell. The shell has a first surface for contacting or opposing the heat exchange element 10 and a second surface not in contact with or opposing the heat exchange element 10. A thermal conductive coating 102 is provided on the first surface, and a thermal insulation coating 103 is provided on the second surface. The thermal conductive coating 102 and the thermal insulation coating 103 are both insulating layers.

[0058] Specifically, the battery 100 may include a plurality of battery cells 101, which may also include a housing. The battery cells 101 are arranged inside the housing. The plurality of battery cells 101 may be evenly arranged in multiple rows and columns within the housing and located on equal height planes. In some cases, adjacent battery cells 101 may be in contact with each other or may have a certain gap therebetween. This gap is controlled within a reasonable range so as to avoid mutual interference and achieve a higher energy density within the housing. The battery cell 101 has a housing, which may be in the form of a rectangular parallelepiped, a cube, or the like.

[0059] In order to meet the heat exchange needs of the battery cell 101, this embodiment further provides a heat exchange element 10. For example, the heat exchange element 10 can be a heat exchange plate, that is, a plate-like structure. There is a liquid flow channel inside the heat exchange element 10, and heat exchange liquid continuously flows. The heat exchange element 10 itself is made of a heat-conducting material. In this way, when the heat exchange element 10 is in contact with the shell, heat exchange can be performed on the battery cell 101, thereby ensuring the normal operation of the battery 100, or heat exchange can be achieved in a relative situation, that is, when the distance is close; the heat exchange element 10 can also be of other types, such as a multi-row tubular structure.

[0060] In this embodiment, the surface of the shell that is in contact with or opposite to the heat exchange element 10 for heat exchange is defined as the first surface, and the surface that is not in contact with or opposite to the heat exchange element 10 is defined as the second surface. Since the first surface needs to conduct heat, a thermal conductive coating 102 is provided on the first surface and a thermal insulation coating 103 is provided on the second surface, and both are insulating layers.

[0061] Compared with the related art that uses a film to wrap the shell, the thermal conductive coating 102 and the thermal insulation coating 103 provided in this embodiment have higher insulation reliability, and the surfaces of the shell are distinguished, and the thermal conductive coating 102 and the thermal insulation coating 103 are set separately, which reduces the impact on the heat exchange effect.

[0062] Related art also involves a single-coat insulation layer. To avoid affecting the heat dissipation effect, a single-layer insulation layer is applied to the surface of the battery cell shell that contacts the heat exchange element. This reduces the insulation reliability of the battery cell. When the battery 100 shell is heated, the insulation material of the cell shell is damaged, resulting in insulation failure. Although the coating method in the related art has a certain insulation effect, it affects the heat transfer effect of the heat exchange surface. Therefore, in order to reduce the impact on the heat transfer effect, only a single-layer coating is provided on the heat exchange surface, which is thinner than other surfaces. Although the provision of this layer reduces the impact on heat transfer, its insulation effect is poor. After the battery cell loses control, the insulation effect of the shell will fail, greatly affecting the reliability of the battery 100. Therefore, in order to solve the above problems, the battery cell 101 of the battery 100 provided in the embodiment of the present application distinguishes each surface. After the distinction, a heat-conductive insulating coating is provided on the heat exchange surface, and a heat-insulating insulating layer is provided on the non-heat exchange surface. In addition, the thermal conductive coating 102 does not need to be set thinner in order not to affect the heat exchange. Therefore, the battery 100 provided in the present application reduces the impact on heat exchange and improves the reliability of the insulation effect.

[0063] It should be noted that the first surface is the heat exchange surface and the second surface is the non-heat exchange surface.

[0064] In some cases, when the heat exchanger 10 is arranged between two adjacent battery cells 101, the two surfaces of the heat exchanger 10 respectively contact the surfaces of the shells of the two adjacent battery cells 101 or have a small gap with the surfaces of the shells. At this time, the surface is the first surface, and a thermal conductive coating 102 is provided on the first surface. Specifically, it can be understood that when the heat exchanger 10 is arranged between two battery cells 101, the shells of the two adjacent battery cells 101 are separated by the heat exchanger 10, and the two shells do not have two surfaces facing each other or in contact. They both face the heat exchanger 10, so this surface is the first surface, and a thermal conductive coating 102 needs to be provided.

[0065] For another example, the heat exchange element 10 can also be arranged at the end of multiple battery cells 101, that is, the heat exchange element 10 is arranged above the end surfaces of multiple battery cells 101 on the same side, and the end surfaces of the shells of multiple battery cells 101 on the same side contact the heat exchange element 10 at the same time, then the end surface on the same side is the first surface, and the thermal conductive coating 102 is set.

[0066] In some embodiments, referring to FIG. 2 , FIG. 3 and FIG. 4 , the second surface of the housing includes a surface facing or in contact with the housing of an adjacent battery cell 101 .

[0067] Specifically, when the battery cells 101 are arranged, adjacent battery cells 101 can form opposing or contacting surfaces. The opposing or contacting surfaces of the two shells are required to have a better insulation effect to reduce the risk of mutual impact in the event of thermal runaway. Therefore, this embodiment provides a second surface that includes a surface opposing or contacting the shell of the adjacent battery cell 101. It can also be understood that in this case, the heat exchange element 10 is not placed between the two shells, and the surfaces of the two shells are directly opposing or contacting.

[0068] The second surface may be the surface of the shells of two battery cells 101 that are opposite or in contact, where opposite refers to two directly opposite surfaces located on two adjacent shells, or in some cases, such as when the battery cells 101 are densely arranged, the two surfaces may be in direct contact, and the two contacting surfaces are the second surfaces.

[0069] Therefore, the thermal insulation coating 103 provided on the second surface of this embodiment can prevent mutual interference between adjacent battery cells due to thermal runaway.

[0070] In some embodiments, please continue to refer to FIG. 2 , FIG. 3 and FIG. 4 , the second surface of the housing may further include a surface that is not opposite to or in contact with the housing of the adjacent battery cell 101 .

[0071] Specifically, after the battery cells 101 are arranged, the housings of the battery cells 101 at the edges have a surface that is not opposite or in contact with the housings of adjacent battery cells 101. This surface can also be used as a second surface and provided with a thermal insulation coating 103 to provide comprehensive insulation protection for the battery cells 101. In this case, the second surface is also not in contact with or opposite the heat exchange element 10.

[0072] In some embodiments, referring to Figures 4 and 5 , the first surface may include the bottom surface 1012 of the battery cell 101, with the heat exchange element 10 positioned directly opposite the bottom surface 1012. Specifically, the direction perpendicular to the opposite end surfaces of the battery cell 101 is defined as the vertical direction (as indicated by the arrow in Figure 5 ), and the bottom surface 1012 of the battery cell 101 refers to the lower end surface. When the battery 100 is in use and placed vertically, the vertical direction is the direction of the arrow, and the first surface is the bottom surface 1012 of the battery cell 101. The "in-use state" can be understood as the state in which the battery 100 is in a stable discharge or charge state, or it can be understood as the state in which it is placed when installed in an electrical device, such as a vehicle 1000. The bottom surface 1012 is the bottommost surface of the battery in the vertical direction (direction of the arrow) when in use. In this case, the heat exchange element 10 can be positioned directly opposite the bottom surface 1012, or it can be understood as the battery cell 101 being placed on the heat exchange element 10.

[0073] The advantage of this embodiment is that the first surface can be the bottom surface 1012 of the battery cell 101, and the heat exchange element 10 can also be used to simultaneously contact the bottom surfaces 1012 of multiple battery cells 101, making the installation of the heat exchange element 10 convenient. Moreover, for common electrical devices, placing the heat exchange element 10 at a relatively low vertical position on the bottom makes the structure more reasonable and easier to assemble.

[0074] Alternatively, in some embodiments, referring to FIG. 5 , the first surface may also include a top surface 1013 of the battery cell 101 , and the heat exchange element 10 is disposed opposite to the top surface 1013 .

[0075] Specifically, the direction perpendicular to the opposite end faces of the battery cell 101 is still considered the vertical direction (as indicated by the arrows in FIG5 ), and the top surface 1013 of the battery cell 101 refers to the upper end face. In some cases, due to specific needs, the cover plate and explosion-proof valve of the battery cell 101 are disposed on the bottom surface 1012 of the battery cell 101. In this case, the first surface is the top surface 1013 of the battery cell 101, and the top surface 1013 is the heat exchange surface. The heat exchange element 10 can be brought into contact with the top surface 1013 of the battery cell 101 to achieve heat exchange.

[0076] The effect of this embodiment is that the position of the heat exchange component 10 is set according to specific usage needs, so that the battery 100 can be better structurally assembled, which not only achieves better heat dissipation but also does not affect the use of the explosion-proof valve. At the same time, for the top surface 1013, one heat exchange component 10 can also simultaneously contact the top surfaces 1013 of multiple battery cells 101 to achieve the heat dissipation effect.

[0077] In some embodiments, referring to Figures 2 and 5 , the first surface includes a side surface 1014 of the battery cell 101, and the heat exchange element 10 is positioned directly opposite the side surface 1014. Specifically, the side surface 1014 is the surface other than the bottom surface 1012 and the top surface 1013. When the battery 100 is installed in an electrical device, in addition to the bottom surface 1012 and the top surface 1013, the surface between the bottom surface 1012 and the top surface 1013 includes the side surface 1014. The heat exchange element 10 can contact this side surface 1014 to achieve heat exchange. Since the battery cells 101 can be arranged in multiple rows and columns, for the side 1014, the side 1014 can be two adjacent surfaces of two battery cells 101. In this case, the heat exchange element 10 can be set between the two adjacent battery cells 101. The side 1014 can also be a surface of a battery cell 101 at a certain edge position that is not opposite to the adjacent battery cell 101. In this case, the heat exchange element 10 can be attached to this surface, and the heat exchange element 10 is not located between the battery cells 101, but can be located as a whole on one side of all the battery cells 101.

[0078] The effect of this embodiment is that the heat exchange surface can be selected according to actual needs based on the arrangement of the battery cell 101 in the box, that is, it can be the side 1014 of the battery cell 101. When the horizontal space in the box is large and the vertical space is small, the first surface can be selected as the side 1014, which facilitates the arrangement of the heat exchange component 10 and increases space utilization.

[0079] In some embodiments, referring to Figures 3 and 5 , the first surface may also include a large surface 1015 of the battery cell 101, with the heat exchange element 10 positioned opposite the large surface 1015. Similarly, for a rectangular battery cell 101, when installed on an electrical device, it has a bottom surface 1012 and a top surface 1013 in the vertical direction (direction of the arrow). The surface between the bottom surface 1012 and the top surface 1013 also includes the large surface 1015. Relative to the side surface 1014, the area of ​​the large surface 1015 is larger than that of the side surface 1014. The effect of this embodiment is that, by using the large surface 1015 as both the first surface and the heat exchange surface, the larger contact and heat exchange area results in a better heat exchange effect.

[0080] It should also be noted that the first surface includes the bottom surface 1012, the top surface 1013, the side surface 1014 and the large surface 1015, which means that the first surface can be one surface, or two or more surfaces. For example, the first surface can be the bottom surface 1012 and the top surface 1013, or the side surface 1014 and the bottom surface 1012, or the bottom surface 1012 and the large surface 1015, or the top surface 1013 and the side surface 1014, or the side surface 1014 and the large surface 1015, etc. That is to say, depending on the different setting positions of the heat exchange element 10 and the different number of heat exchange elements 10 set, the bottom surface 1012 and the top surface 1013 of the battery cell 101 can be the first surface at the same time. For example, the heat exchange elements 10 are respectively set at the opposite ends of the battery cell 101. At this time, the bottom surface 1012 and the top surface 1013 of the battery cell 101 are both the first surfaces, and a thermal conductive coating 102 needs to be set to exchange heat with the heat exchange element 10; for another example, when heat exchange elements 10 are set on the top surface 1013 and the bottom surface 1012 of the battery cell 101 and between two adjacent battery cells 101, the bottom surface 1012, top surface 1013 and side surface 1014 or large surface 1015 of the battery cell 101 are all the first surfaces at the same time, and a thermal conductive coating 102 needs to be set to exchange heat with the heat exchange element 10.

[0081] It should also be noted that the second surface and the first surface can be selected according to specific needs during actual configuration. On the battery cell shell, the same surface cannot be both the first surface and the second surface, but rather one of the first surface and the second surface. The above embodiment illustrates that the first surface may include the bottom surface 1012, the top surface 1013, the side surface 1014, and the large surface 1015. When one or more of the bottom surface 1012, the top surface 1013, the side surface 1014, and the large surface 1015 are non-heat exchange surfaces, the second surface may be used to provide the thermal insulation coating 103. The above embodiment also illustrates that the second surface may include a surface that is or is not opposite to or in contact with an adjacent shell. However, if this surface is used for heat exchange, this surface may be the first surface used to provide the thermal conductive coating 102.

[0082] According to an embodiment of the present application, the thermal insulation coating 103 is a heat-resistant material layer. The function of the thermal insulation coating 103 is to insulate heat, specifically to isolate the heat between two adjacent battery cells 101, reduce the risk of mutual interference, and at the same time ensure the heat resistance of the thermal insulation coating 103, so this embodiment provides a thermal insulation coating 103 using a heat-resistant material layer. The heat-resistant material can be an inorganic compound or a polymer, so that it has a good high temperature tolerance. At the same time, in order to ensure the insulation effect, the heat-resistant material layer provided in this embodiment adopts an insulating material. The effect of the thermal insulation coating 103 provided in this embodiment using a heat-resistant material layer is that it can withstand high temperatures, and the risk of damage due to continuous operation at high temperatures is small, which ensures the independent operation of adjacent battery cells 101 without mutual interference, that is, when a battery cell 101 has thermal runaway, the impact of the battery cell 101 on the adjacent battery cell 101 is reduced.

[0083] In some embodiments, the thermal conductive coating 102 may be a ceramic-based composite material layer, or a resin-based composite material layer, or may include both a ceramic-based composite material layer and a resin-based composite material layer.

[0084] Ceramic-based composites and resin-based composites are both fiber-reinforced composites. Fiber-reinforced composites can be categorized as resin-based, metal-based, and ceramic-based composites. Since metal-based composites are non-insulating materials, this embodiment utilizes ceramic-based composites and / or resin-based composites from the fiber-reinforced composites.

[0085] Ceramic-based composites (CMCs) are composite materials composed of ceramics as a matrix and other materials. The ceramic matrix can be silicon nitride, silicon carbide, boron nitride, etc., and features high temperature resistance, high strength and rigidity, relatively low weight, and corrosion resistance. However, since the thermal coating 102 is an insulating layer, the CMC is entirely insulated and can be a composite material of ceramic and non-metallic materials. In this embodiment, the CMC is used to manufacture the thermal coating 102, which provides excellent high temperature resistance, strength, and rigidity, reducing the risk of insulation failure during thermal runaway.

[0086] The resin-based composite material layer is a reinforcing material with an organic polymer as the matrix, such as epoxy resin, unsaturated polyester resin, phenolic resin, polyurethane, etc. Resin-based composite materials are mainly divided into two categories: thermosetting resin-based composite materials and thermoplastic resin-based composite materials. Thermosetting resin-based composite materials are composite materials made of thermosetting resins such as unsaturated polyester resins, epoxy resins, and phenolic resins as the matrix, and glass fiber, carbon fiber, aramid fiber, etc. as reinforcing materials. They have excellent chemical stability, electrical insulation, corrosion resistance, good bonding properties and high mechanical strength. Epoxy resin has excellent physical, mechanical and electrical insulation properties, corrosion resistance, chemical stability, and bonding properties with various materials. In this embodiment, the use of resin-based composite materials to make the thermal conductive coating 102 has good mechanical strength and insulation, etc., reducing the risk of insulation failure during thermal runaway.

[0087] Alternatively, the thermal conductive coating 102 in this embodiment may also include both a ceramic-based composite material layer and a resin-based composite material layer, thereby combining the advantages of both.

[0088] It should be noted that the thermal conductive coating 102 in this embodiment is made of a thermally conductive ceramic-based composite material layer, a resin-based composite material layer, or a combination of the two.

[0089] In order not to affect the heat dissipation effect in the related art, a single insulating layer is coated on the surface of the battery cell shell that contacts the heat exchange element 10. This reduces the insulation reliability of the battery cell. When the battery shell is heated, the insulating material of the battery cell shell will be damaged, resulting in insulation failure.

[0090] The thermal conductive coating 102 in this embodiment adopts ceramic-based composite materials, resin-based composite materials or both. Both ceramic-based composite materials and resin-based composite materials are fiber-reinforced composite materials, have high mechanical strength, and can conduct heat. While ensuring the heat exchange effect, it will not be damaged when the battery cell is in thermal runaway, and the shell can still maintain effective insulation, which greatly improves the reliability of the battery cell 101 shell insulation. Compared with the insulation in the form of a coating, the manufacturing process is simple and fast, and will not produce bubbles as generated on the coating surface in the coating process, and will not affect the insulation and withstand voltage performance of the battery cell. Compared with a single-layer coating, the thermal conductive coating 102 in this embodiment has high mechanical strength and can prevent insulation damage caused by thermal runaway.

[0091] In some embodiments, the thermal conductive coating 102 may also be a thermally conductive ceramic resin matrix composite material layer. The ceramic resin matrix composite material layer is a composite material with ceramic and resin as matrices, which combines the excellent properties of both.

[0092] In some embodiments, thermal insulation coating 103 can be a ceramic-based composite material coating, a resin-based composite material coating, both, or a ceramic-resin-based composite material layer. Unlike thermal conductive coating 102, thermal insulation coating 103 is made of a non-thermal conductive material, i.e., a heat-insulating material, while thermal conductive coating 102 is made of a heat-conductive material. In addition to the aforementioned benefits, thermal insulation materials also provide thermal insulation, isolating adjacent battery cells 101 from each other and preventing interference.

[0093] In some embodiments, the thermal conductive coating 102 is a material layer combining boron nitride and water-based epoxy resin.

[0094] This embodiment uses a material layer combining boron nitride and water-based epoxy resin.

[0095] Boron nitride is a high-performance ceramic material with excellent thermal conductivity, insulation, and high-temperature resistance. Modification can improve the toughness, adhesion, and compatibility of boron nitride with epoxy resin, further enhancing the overall performance of the coating.

[0096] Epoxy resin is a resin material with excellent mechanical properties, corrosion resistance, and insulation properties. Waterborne epoxy resin is dispersed in water and offers advantages such as environmental friendliness, low toxicity, and ease of application. The combination of waterborne epoxy resin and modified boron nitride fully leverages the advantages of both, improving the overall performance of the coating.

[0097] Specifically, pure epoxy resin has a relatively low thermal conductivity. In order to improve the thermal conductivity of pure epoxy resin materials, fillers with good thermal conductivity are added to the matrix. Filled thermal conductive epoxy resin materials meet the thermal conductivity requirements by adding inorganic thermal conductive fillers without affecting the original comprehensive properties of the resin. Boron nitride is an excellent thermal conductive material and can be used as a filler. That is, boron nitride can be added to water-based epoxy resin as a reinforcing agent to prepare a boron nitride / epoxy resin composite coating, which can greatly improve the mechanical properties, thermal conductivity and heat resistance of the coating. At the same time, boron nitride can be modified. Unmodified boron nitride has poor compatibility with the resin matrix and exists in the form of agglomerates when added. It is irregular and disorderly distributed, which is not conducive to improving the performance of epoxy resin coatings. Boron nitride can be modified, its orientation can be directionally changed, and composite nanofillers can be added to enhance its compatibility with the resin.

[0098] Therefore, the material layer combining boron nitride and water-based epoxy resin is specifically a thermally conductive insulating coating combining modified boron nitride and water-based epoxy resin, which has excellent mechanical properties, high mechanical strength, good thermal conductivity, and stable insulation. It can still maintain good insulation when thermal runaway occurs in the battery cell 101.

[0099] In some embodiments, the thermally conductive coating 102 may also be an epoxy resin-based thermally conductive insulating coating modified by epoxy-based polyhedral silsesquioxane.

[0100] Epoxy-based polyhedral oligomeric silsesquioxanes not only possess the toughness, low cost, and good processability of polymer materials, but also possess the advantages of inorganic materials, such as high strength, low oxidation resistance, high temperature resistance, and excellent mechanical properties. Currently, the use of epoxy-based polyhedral oligomeric silsesquioxanes as nanostructured components in the preparation of organic-inorganic hybrid materials can enhance the thermal stability, mechanical properties, and other physical properties of the materials.

[0101] The specific operation is to hydrolyze and condense vinyltrichlorosilane to obtain octavinyl polyhedral silsesquioxane; the vinyl group of octavinyl polyhedral silsesquioxane and the allyl group of allyl glycidyl ether are catalytically polymerized to obtain epoxy polyhedral silsesquioxane; then isophorone diisocyanate and hydroxyethyl methacrylate are used for in-situ polymerization modification on the surface of aluminum oxide and carbon fiber; finally, epoxy resin is filled and the epoxy resin is modified with epoxy polyhedral silsesquioxane, and when used, it is mixed with a curing agent, sprayed, and dried to obtain an epoxy resin-based thermal conductive insulating coating modified with epoxy polyhedral silsesquioxane.

[0102] The epoxy resin is modified with epoxy polyhedral silsesquioxane. The presence of the Si-O skeleton not only effectively improves the thermal and flame retardant properties of the epoxy resin, but also makes the coating less likely to crack and fall off and has stable insulation properties. It can still maintain good insulation properties when thermal runaway occurs in the battery cell 101.

[0103] In some embodiments, the thermal insulation coating 103 is a nano-composite ceramic-based resin insulation layer or a high-temperature resistant ceramic insulation layer.

[0104] Nano-ceramic materials have good hardness, fracture toughness, and low-temperature ductility, which greatly improves the mechanical properties of nano-composite ceramic-based resins, especially hardness and strength. The resin has insulating and heat-insulating effects, which enables the thermal insulation coating 103 to effectively insulate and insulate, and has strong mechanical strength, which can keep the shell insulated even when the battery cell 101 experiences thermal runaway. High-temperature resistant ceramics have excellent high-temperature resistance, corrosion resistance, low thermal conductivity, good thermal stability, and wear resistance. Specifically, ZrO2 can be used, which has a high melting point, low thermal conductivity, and a small expansion coefficient.

[0105] As a specific embodiment of the present application, the heat exchange element 10 included in the battery 100 is a heat exchange plate. The first surface in contact with the heat exchange element 10 is the bottom surface 1012 of the shell of the battery cell 101. The battery cell 101 is in the shape of a rectangular parallelepiped. There are multiple battery cells 101. The heat exchange element 10 is arranged at the bottom of the multiple battery cells 101. The surface opposite to adjacent battery cells 101 is the second surface. A thermal conductive coating 102 is arranged on the first surface, and a thermal insulation coating 103 is arranged on the second surface. The thermal conductive coating 102 is a material layer combining boron nitride and water-based epoxy resin, and the thermal insulation coating 103 adopts a nano-composite ceramic-based resin insulation layer. Therefore, the battery 100 provided in this specific embodiment has a good heat exchange effect, and when the battery cell is in thermal runaway, the insulation of the shell will not fail due to the presence of the thermal conductive coating 102 and the thermal insulation coating 103 with good performance.

[0106] Secondly, the present application also provides an electrical device, comprising the battery 100 provided by any of the above embodiments. Since the battery 100 has good insulation reliability and the heat exchange effect is not reduced, the continuous and reliable operation of the electrical device is ensured.

[0107] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery, characterized in that: It includes a heat exchange element and multiple battery cells, the battery cells include a shell, the shell has a first surface in contact with or opposite to the heat exchange element and a second surface not in contact with or opposite to the heat exchange element, a thermal conductive coating is provided on the first surface, and a thermal insulation coating is provided on the second surface, and the thermal conductive coating and the thermal insulation coating are both insulating layers.

2. The battery according to claim 1, wherein The second surface includes a surface facing or in contact with a casing of an adjacent battery cell.

3. The battery according to claim 1 or 2, characterized in that The second surface includes a surface that is not opposite to or in contact with a casing of an adjacent battery cell.

4. The battery according to any one of claims 1 to 3, characterized in that The first surface includes the bottom surface of the battery cell, and the heat exchange element is arranged facing the bottom surface.

5. The battery according to any one of claims 1 to 4, characterized in that The first surface includes the top surface of the battery cell, and the heat exchange element is arranged facing the top surface.

6. The battery according to any one of claims 1 to 5, characterized in that The first surface includes a side surface of the battery cell, and the heat exchange element is arranged facing the side surface.

7. The battery according to any one of claims 1 to 6, characterized in that The first surface includes a large surface of the battery cell, and the heat exchange element is arranged facing the large surface.

8. The battery according to any one of claims 1 to 7, characterized in that The heat-insulating coating is a heat-resistant material layer.

9. The battery according to any one of claims 1 to 8, characterized in that The thermal conductive coating is a ceramic-based composite material layer and / or a resin-based composite material layer.

10. The battery according to any one of claims 1 to 9, characterized in that The thermal conductive coating is a ceramic resin-based composite material layer.

11. The battery according to any one of claims 1 to 10, wherein The thermal insulation coating is a ceramic-based composite material coating and / or a resin-based composite material coating.

12. The battery according to any one of claims 1 to 11, wherein The thermal insulation coating is a ceramic resin-based composite material layer.

13. The battery according to any one of claims 1 to 12, wherein The thermal conductive coating is a material layer combining boron nitride and water-based epoxy resin.

14. The battery according to any one of claims 1 to 13, wherein The thermal conductive coating is an epoxy resin-based thermal conductive insulating coating modified by epoxy-based polyhedral silsesquioxane.

15. The battery according to any one of claims 1 to 14, characterized in that The heat-insulating coating is a nano-composite ceramic-based resin insulating layer or a high-temperature resistant ceramic insulating layer.

16. An electrical device, characterized in that: The electrical device comprises the battery according to any one of claims 1 to 15.

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