Insulating film, battery cell, battery, and electric device

Abstract

The embodiment of the utility model provides an insulating film, a battery monomer, a battery and electric equipment. The battery cell includes an electrode assembly, a case, and an insulating film. The electrode assembly includes a plurality of surfaces, the plurality of surfaces including a first surface, the first surface being a surface having a largest area among the plurality of surfaces. The case forms an accommodation space that accommodates the electrode assembly. The insulating film wraps the periphery of the electrode assembly and is located between the electrode assembly and the shell, the insulating film is provided with a first thickness area and a second thickness area, the thickness of the first thickness area is larger than that of the second thickness area, and the first thickness area is located in the area where the first surface of the electrode assembly is located. According to the battery monomer provided by the embodiment of the invention, when short circuit, overcharge and internal thermal runaway of the electrode assembly occur, the condition that heat is quickly transferred to the shell can be improved, the heat insulation protection effect of the insulating film is improved, and the reliability of the battery monomer is further improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to insulating films, battery cells, batteries and electrical equipment. Background Art

[0002] This section is intended to provide a background or context for the embodiments of the present application. No description herein is admitted to be prior art by virtue of its inclusion in this section.

[0003] In the battery assembly process, after the bare cell is assembled, there is a shelling process. When the bare cell is placed in the shell, in order to protect the bare cell and provide insulation, a layer of Mylar film, also known as Mylar film, will be coated on the outer surface of the bare cell. In the related art, during the battery charging and discharging process, the bare cell expands, which can easily cause the large surface of the bare cell to be squeezed and contacted with the shell, while the side of the bare cell is not easy to contact with the shell. When thermal runaway occurs inside the bare cell, heat is more easily transferred to the large surface of the aluminum shell, resulting in poor thermal insulation. Utility Model Content

[0004] In view of this, the embodiments of the present application hope to provide an insulating film, a battery cell, a battery and an electrical device that can improve the heat insulation effect.

[0005] To achieve the above-mentioned purpose, a first aspect of an embodiment of the present application provides a battery cell, comprising:

[0006] An electrode assembly, the electrode assembly comprising a plurality of surfaces, the plurality of surfaces comprising a first surface, the first surface being a surface with the largest area among the plurality of surfaces;

[0007] A shell, forming a receiving space for receiving the electrode assembly;

[0008] An insulating film, which is coated on the periphery of the electrode assembly and is located between the electrode assembly and the shell, and has a first thickness region and a second thickness region, the thickness of the first thickness region is greater than the thickness of the second thickness region, wherein the first thickness region is located in the region where the first surface of the electrode assembly is located.

[0009] The battery cell provided in the embodiment of the present application includes an electrode assembly and an insulating film. The insulating film is provided with a first thickness region and a second thickness region, and the thickness of the first thickness region is greater than the thickness of the second thickness region. The first thickness region is provided in the area where the first surface of the electrode assembly is located, that is, the thickness of the insulating film covering at least a part of the first surface of the electrode assembly is greater than the thickness of the insulating film covering other surfaces of the electrode assembly except the first surface. In this way, when the electrode assembly is short-circuited, overcharged, or has internal thermal runaway, the rapid transfer of heat to the outer shell can be improved, the thermal insulation protection effect of the insulating film can be improved, and the reliability of the battery cell can be improved.

[0010] In some embodiments, the insulating film is formed by folding a substrate, and the insulating film includes an overlapping region where the substrate is overlapped, and the overlapping region constitutes the first thickness region.

[0011] In this way, the thickness of the insulating film in the area where the first surface of the electrode assembly is located is greater than the thickness of the insulating film on other surfaces, thereby increasing the thickness of the insulating film between the area where the first surface of the electrode assembly is located and the outer shell, thereby improving the thermal insulation effect of the insulating film.

[0012] In some embodiments, the length of the electrode assembly is L0, and the dimension of the first thickness region along the length direction of the electrode assembly is L1, wherein the ratio of L1 to L0 is in the range of 0.8-1.

[0013] While ensuring that the insulating film corresponding to the first surface of the electrode assembly has sufficient structural strength and heat insulation effect, the assembly of the battery cell is not affected and the structural compactness and performance of the battery cell can be maintained.

[0014] In some embodiments, the insulating film is formed by folding a substrate, and the thickness of the substrate is 0.05 mm-0.3 mm.

[0015] On the one hand, the thickness of the insulating film corresponding to the first surface of the electrode assembly can be increased, thereby better playing the role of heat insulation protection. On the other hand, when the thickness of the insulating film corresponding to the first surface of the electrode assembly remains the same, the thickness of the insulating film corresponding to the side of the electrode assembly can be reduced, thereby reducing the cost of the battery.

[0016] In some embodiments, the insulating film is formed by folding a substrate, the substrate having a first wall thickness region and a second wall thickness region, the thickness of the first wall thickness region is greater than the thickness of the second wall thickness region, wherein the first wall thickness region is folded to form the first thickness region, and the second wall thickness region is folded to form the second thickness region.

[0017] In this way, the thickness of the insulating film in the area where the first surface of the electrode assembly is located is greater than the thickness of the insulating film on other surfaces, thereby increasing the thickness of the insulating film between the first surface of the electrode assembly and the outer shell, thereby improving the thermal insulation effect of the insulating film.

[0018] In some embodiments, the battery cell includes a shell, the electrode assembly coated with the insulating film is disposed in the shell, and the distance between the top of the insulating film and the top cover of the shell is 0.1 mm-5 mm.

[0019] This is beneficial for achieving connection between the insulating film and the top cover while minimizing the impact on assembling the top cover to the shell.

[0020] In some embodiments, the number of the electrode assembly is one, and the first thickness region is disposed in regions where the two first surfaces of the electrode assembly are located.

[0021] In this way, the heat insulation protection effect of the insulating film is further improved, and the reliability of the battery cell is further improved.

[0022] In some embodiments, the battery cell includes a shell, the electrode assembly is arranged in the shell, the number of the electrode assemblies is two, the first surfaces of the two electrode assemblies opposite to each other are both provided with the first thickness region, and the first surfaces of the two electrode assemblies opposite to each other are not provided with the first thickness region.

[0023] In this way, while improving the heat insulation protection effect of the insulating film, the space occupied by the insulating film can also be reduced, which is beneficial to improving the performance of the battery.

[0024] In some embodiments, the insulating film includes a substrate and a sprayed layer, and a partial area of ​​the substrate is provided with the sprayed layer to form the first thickness area.

[0025] Here, an insulating spray coating is formed by spraying a ceramic coating or the like on a substrate corresponding to the first surface of the electrode assembly, thereby increasing the thickness of the insulating film corresponding to the first surface of the electrode assembly and improving the heat insulation effect of the insulating film.

[0026] In some embodiments, the insulating film includes a substrate and a coding resin, and a partial area of ​​the substrate is provided with the coding resin to form the first thickness area.

[0027] Here, by providing a coding glue on the substrate corresponding to the first surface of the electrode assembly, the thickness of the insulating film corresponding to the first surface of the electrode assembly is increased, thereby improving the heat insulation effect of the insulating film.

[0028] A second aspect of an embodiment of the present application provides an insulating film, which is used as the battery cell mentioned above, and is used to wrap an electrode assembly of the battery cell.

[0029] The insulating film provided in the embodiment of the present application is provided with a first thickness region and a second thickness region, wherein the thickness of the first thickness region is greater than the thickness of the second thickness region, and the first thickness region is provided on the first surface of the electrode assembly, that is, the thickness of the insulating film covering at least a portion of the first surface of the electrode assembly is greater than the thickness of the insulating film covering other surfaces of the electrode assembly except the first surface. In this way, when the electrode assembly is short-circuited, overcharged, or has internal thermal runaway, the rapid transfer of heat to the outer casing can be improved, thereby improving the thermal insulation protection effect of the insulating film and thereby improving the reliability of the battery cell.

[0030] In some embodiments, the insulating film is formed by folding a substrate having a bottom covering wall, a first side covering wall, and a second side covering wall, wherein the area of ​​the second side covering wall is greater than the area of ​​the first side covering wall; and when the substrate is in an unfolded state, the bottom covering wall is respectively connected to one of the first side covering walls at both ends along the first direction, and each of the first side covering walls is respectively connected to one of the second side covering walls at both ends along the second direction, wherein the first direction intersects with the second direction.

[0031] By arranging the insulating film to overlap at the first surface of the electrode assembly, the thickness of the insulating film between the first surface of the electrode assembly and the outer shell is increased, thereby improving the heat insulation effect of the insulating film.

[0032] A third aspect of an embodiment of the present application provides a battery, comprising at least one battery cell as described above.

[0033] The insulating film of the battery provided in the embodiment of the present application is provided with a first thickness region and a second thickness region, wherein the thickness of the first thickness region is greater than that of the second thickness region, and the first thickness region is provided in the region where the first surface of the electrode assembly is located, that is, the thickness of the insulating film covering at least a portion of the first surface of the electrode assembly is greater than the thickness of the insulating film covering other surfaces of the electrode assembly except the first surface. In this way, when the electrode assembly is short-circuited, overcharged, or has internal thermal runaway, the rapid transfer of heat to the outer casing can be improved, thereby improving the thermal insulation protection effect of the insulating film and thereby improving the reliability of the battery cell.

[0034] A fourth aspect of an embodiment of the present application provides an electrical device, comprising the battery described above, wherein the battery is used to provide electrical energy.

[0035] The insulating film of the battery of the electrical equipment provided in the embodiment of the present application is provided with a first thickness region and a second thickness region, the thickness of the first thickness region is greater than the thickness of the second thickness region, and the first thickness region is provided in the region where the first surface of the electrode assembly is located, that is, the thickness of the insulating film covering at least a part of the first surface of the electrode assembly is greater than the thickness of the insulating film covering other surfaces of the electrode assembly except the first surface. In this way, when the electrode assembly is short-circuited, overcharged, or has internal thermal runaway, the rapid transfer of heat to the outer casing can be improved, the thermal insulation protection effect of the insulating film can be improved, and the reliability of the battery cell can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A schematic diagram of the structure of a vehicle provided in one embodiment of the present application;

[0037] Figure 2 A three-dimensional exploded schematic diagram of a battery provided in one embodiment of the present application;

[0038] Figure 3 A schematic diagram of the structure of a battery cell provided in one embodiment of the present application;

[0039] Figure 4 for Figure 3 A three-dimensional exploded schematic diagram of a battery cell shown;

[0040] Figure 5 for Figure 4 A schematic diagram of the structure of the insulating film shown;

[0041] Figure 6 This is a schematic structural diagram of a substrate provided in an embodiment of the present application in an unfolded state.

[0042] Description of Reference Numerals

[0043] 1. Insulating film; 11. Base material; 111. Second side covering wall; 112. First side covering wall; 113. Bottom covering wall; 2. Electrode assembly; 3. Outer shell; 31. Shell; 32. Top cover; 4. Blue film; 5. Bottom support plate; 6. Adapter; 10. Battery cell; 20. Battery box; 21. First box body; 22. Second box body; 100. Battery; 200. Controller; 300. Motor; 1000. Vehicle. DETAILED DESCRIPTION

[0044] It should be noted that, in the absence of conflict, the embodiments and technical features in the embodiments of the present application can be combined with each other, and the detailed description in the specific implementation method should be understood as an explanation of the purpose of the present application and should not be regarded as an improper limitation on the present application.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field 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 this application are intended to cover non-exclusive inclusions.

[0046] In the description of the embodiments of the present application, the technical terms "first", "second", "third", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0047] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0048] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0049] In the description of the embodiments of the present application, the orientation or position relationship indicated by technical terms such as "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "circumferential", "height direction", "first direction", and "second direction" are based on the orientation or position relationship shown in the accompanying drawings. They 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 referred device or element must have a specific orientation, be constructed, operated or used in a specific orientation. Therefore, they should not be understood as limitations on the embodiments of the present application.

[0050] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0051] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, the technical term "contact" should be understood in a broad sense, and may be direct contact or contact through an intermediate medium layer. It may be contact with essentially no interaction force between the two contacting parties, or it may be contact with interaction force between the two contacting parties.

[0052] With the development of clean energy, more and more devices use electric energy as driving energy, and then power batteries that can store more electric energy and can be charged and discharged repeatedly are developing rapidly, such as lithium-ion batteries. Among them, power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as aerospace and other fields.

[0053] With the country's vigorous promotion of new energy vehicles, new energy vehicles have ushered in a great opportunity for development. The safety and stability of automobiles have always been people's greatest concern. Therefore, improving the safety of new energy vehicles will be one of the important factors that determine whether new energy vehicles can be quickly popularized. Improving the safety of batteries is an important way to improve the safety of new energy vehicles.

[0054] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module or a battery pack. The battery generally includes a box for encapsulating one or more battery cells. The box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

[0055] The battery cell includes an electrode assembly and an electrolyte. The electrode assembly is composed of a positive electrode sheet, a negative electrode sheet and a separator. The battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode collector. The positive electrode collector not coated with the positive electrode active material layer protrudes from the positive electrode collector coated with the positive electrode active material layer. The positive electrode collector not coated with the positive electrode active material layer serves as the positive electrode tab. Taking lithium-ion batteries as an example, the material of the positive electrode collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. The negative electrode sheet includes a negative electrode collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode collector. The negative electrode collector not coated with the negative electrode active material layer protrudes from the negative electrode collector coated with the negative electrode active material layer. The negative electrode collector not coated with the negative electrode active material layer serves as the negative electrode tab. The negative electrode current collector may be made of copper, and the negative electrode active material may be carbon or silicon. In order to ensure that a large current can pass without melting, the positive electrode tabs are multiple and stacked together, and the negative electrode tabs are multiple and stacked together. The material of the separator may be PP (polypropylene) or PE (polyethylene).

[0056] Illustratively, the positive electrode current collector has two surfaces opposite to each other in its thickness direction, and the positive electrode active material is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.

[0057] Exemplarily, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0058] Illustratively, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0059] For example, the negative electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used.

[0060] Illustratively, the negative electrode current collector has two surfaces opposite to each other in its own thickness direction, and the negative electrode active material is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.

[0061] Exemplarily, the negative electrode active material may adopt the negative electrode active material for the battery known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0062] The battery cell also includes an insulating film and a shell. The insulating film is coated on the outside of the electrode assembly, and the shell encapsulates the electrode assembly coated with the insulating film to form a battery cell. The insulating film can be a Mylar film, and the shell can be an aluminum shell or a steel shell. After the electrode assembly is wound and formed, the Mylar film and the shell are encapsulated through the Mylar wrapping process and the shelling process. Among them, the Mylar film plays the role of sealing and protecting the electrode assembly, and the Mylar film can effectively insulate the electrode assembly and the shell from each other to avoid internal short circuits in the battery cell. The shell plays a protective role.

[0063] Exemplarily, the housing includes a top cover and a shell, the shell is provided with an opening, and the top cover closes the opening to form a closed space for accommodating substances such as the electrode assembly and the electrolyte. The shell may be provided with one or more openings. The top cover may also be provided with one or more openings.

[0064] Exemplarily, at least one electrode terminal is provided on the housing, and the electrode terminal is electrically connected to the electrode tab of the electrode assembly. The electrode terminal can be directly connected to the electrode tab, or indirectly connected to the electrode tab through an adapter. The electrode terminal can be provided on the top cover, or on the housing.

[0065] Exemplarily, an explosion-proof valve is provided on the housing, and the explosion-proof valve is used to release the internal pressure of the battery cell.

[0066] Exemplarily, the battery cells may be cylindrical battery cells, prismatic battery cells, soft-pack battery cells or battery cells 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. There are no particular limitations on the embodiments of the present application.

[0067] Exemplarily, the battery cell further includes a pressure relief structure, which may be disposed on the top cover or the outer shell to release the internal pressure or temperature of the battery cell.

[0068] The development of battery technology must take into account many design factors at the same time, such as energy density, discharge capacity, charge and discharge rate and other performance parameters. In addition, battery reliability must also be considered.

[0069] The battery cell includes a shell, a top cover, an insulating member, an electrode assembly and an insulating film. The top cover closes the opening of the shell, the electrode assembly is arranged in the shell, and the insulating member is arranged between the top cover and the electrode assembly. The insulating member abuts against the electrode assembly to achieve the positioning of the electrode assembly. The insulating film wraps at least a portion of the electrode assembly and the insulating member to insulate and isolate the electrode assembly from the shell. In the related art, after the battery cell is charged and discharged, the electrode assembly expands in the thickness direction, which easily makes the large surface (first surface) of the electrode assembly squeezed and contacted with the shell, while the side surface (other surfaces except the first surface) of the electrode assembly is not easy to contact with the shell. Therefore, when thermal runaway occurs inside the electrode assembly, the internal temperature of the electrode assembly rises sharply, and the large surface of the electrode assembly easily melts the insulating film, so that the heat is transferred to the large surface of the shell, and then transferred to the adjacent battery cells, causing heat diffusion of the adjacent battery cells, and fire and explosion.

[0070] In view of this, in order to improve the reliability of a battery cell, an embodiment of the present application provides a battery cell, which includes an electrode assembly, a shell and an insulating film. The electrode assembly includes multiple surfaces, the multiple surfaces include a first surface, and the first surface is the surface with the largest area among the multiple surfaces. The shell forms a storage space for accommodating the electrode assembly. The insulating film is coated on the periphery of the electrode assembly and is located between the electrode assembly and the shell. The insulating film has a first thickness region and a second thickness region, and the thickness of the first thickness region is greater than the thickness of the second thickness region, wherein the first thickness region is located in the region where the first surface of the electrode assembly is located.

[0071] The battery cell provided in the embodiment of the present application includes an electrode assembly, a shell and an insulating film. The insulating film is provided with a first thickness region and a second thickness region, the thickness of the first thickness region is greater than the thickness of the second thickness region, and the first thickness region is provided in the region where the first surface of the electrode assembly is located, that is, the thickness of the insulating film covering at least part of the first surface of the electrode assembly is greater than the thickness of the insulating film covering other surfaces of the electrode assembly except the first surface. In this way, when the electrode assembly is short-circuited, overcharged, or has internal thermal runaway, the rapid transfer of heat to the shell can be improved, the heat insulation protection effect of the insulating film can be improved, and the reliability of the battery cell can be improved.

[0072] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using batteries.

[0073] The battery mentioned in the embodiments of the present application refers to a battery cell including at least one battery cell provided in the embodiments of the present application. One or more battery cells provide a single physical module with higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module or a battery pack. The battery generally includes a box for encapsulating one or more battery cells. The box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

[0074] The electrical device may be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, and the like; the spacecraft may include an airplane, a rocket, a space shuttle, and 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 electric tool may include a metal cutting electric tool, a grinding electric tool, an assembly electric tool, and an electric tool for railways, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator, and an electric planer, and the like. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0075] It should be noted that the technical solutions described in the embodiments of the present application are not limited to the batteries and electrical devices described above, but can also be applied to all batteries including a box and electrical devices using batteries. However, for the sake of simplicity, the following embodiments are described using electric vehicles as examples.

[0076] Please refer to Figure 1 , a controller 200, a motor 300 and a battery 100 may be arranged inside the vehicle 1000, and the controller 200 is used to control the battery 100 to power the motor 300. For example, the battery 100 may be arranged at the bottom, front or rear of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source for the vehicle 1000, for the circuit system of the vehicle 1000, for example, for the working power requirements during the start-up, navigation and operation of the vehicle 1000. In another embodiment of the present application, the battery 100 may not only be used 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.

[0077] In order to meet different power requirements, the battery 100 may include a plurality of battery cells 10, which refers to the smallest unit that constitutes a battery module or a battery pack. A plurality of battery cells 10 may be connected in series, in parallel, or in a hybrid connection, and a hybrid connection refers to a plurality of battery cells 10 that are both connected in series and in parallel. A plurality of battery cells 10 may be directly connected in series, in parallel, or in a hybrid connection, and then the whole formed by the plurality of battery cells 10 may be accommodated in the battery box 20; of course, the battery 100 may also be a plurality of battery cells 10 that are first connected in series, in parallel, or in a hybrid connection to form a battery module, and then the plurality of battery modules are connected in series, in parallel, or in a hybrid connection to form a whole, and accommodated in the battery box 20. The battery 100 may also include other structures, for example, the battery 100 may also include a confluence component for realizing electrical connection between the plurality of battery cells 10. Each battery cell 10 may be a secondary battery or a primary battery; it may also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 10 may be cylindrical, flat, rectangular, or in other shapes.

[0078] Please refer to Figure 2 The battery 100 includes a battery box 20 and at least one battery cell 10 , and the battery cell 10 is disposed in an installation space of the battery box 20 .

[0079] The battery box 20 can be a simple three-dimensional structure such as a single cuboid, cylinder or sphere, or a complex three-dimensional structure composed of simple three-dimensional structures such as cuboids, cylinders or spheres. The material of the battery box 20 can be alloy materials such as aluminum alloy, iron alloy, etc., or polymer materials such as polycarbonate, polyisocyanurate foam plastics, or composite materials such as glass fiber and epoxy resin.

[0080] The battery box 20 is used to accommodate the battery cell 10, and the battery box 20 can be a variety of structures. In some embodiments, the battery box 20 may include a first box body 21 and a second box body 22, the first box body 21 and the second box body 22 cover each other, and the first box body 21 and the second box body 22 jointly define an installation space for accommodating the battery cell 10. The second box body 22 may be a hollow structure with one end open, the first box body 21 is a plate-like structure, and the first box body 21 covers the open side of the second box body 22 to form a battery box 20 with an installation space; the first box body 21 and the second box body 22 may also be a hollow structure with one side open, and the open side of the first box body 21 covers the open side of the second box body 22 to form a battery box 20 with an installation space. Of course, the first box body 21 and the second box body 22 may be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0081] In order to improve the sealing performance after the first box body 21 and the second box body 22 are connected, a sealing member, such as a sealant, a sealing ring, etc., may also be provided between the first box body 21 and the second box body 22 .

[0082] Assuming that the first box body portion 21 covers the top of the second box body portion 22 , the first box body portion 21 can also be referred to as an upper box cover, and the second box body portion 22 can also be referred to as a lower box cover.

[0083] The present application embodiment provides a battery cell 10. Figures 3 to 6 The battery cell 10 includes an electrode assembly 2, a shell and an insulating film 1. The electrode assembly 2 includes multiple surfaces, the multiple surfaces include a first surface, and the first surface is the surface with the largest area among the multiple surfaces. The shell forms a storage space for accommodating the electrode assembly 2. The insulating film 1 is coated on the periphery of the electrode assembly 2 and is located between the electrode assembly 2 and the shell 3. The insulating film 1 has a first thickness region and a second thickness region. The thickness of the first thickness region is greater than the thickness of the second thickness region. Among them, the first thickness region is located in the area where the first surface of the electrode assembly 2 is located.

[0084] Exemplarily, the battery cell 10 includes a housing 3 , an insulating film 1 is coated on the outside of the electrode assembly 2 , and the housing 3 encapsulates the electrode assembly 2 coated with the insulating film 1 to form the battery cell 10 .

[0085] It should be noted that the first surface described in the embodiment of the present application is the large surface of the electrode assembly 2 , which is the surface with the largest area among the multiple surfaces of the electrode assembly 2 .

[0086] Taking the square battery cell 10 as an example, in the vertical state, the surface formed by the length and width directions of the battery cell 10 is the bottom surface of the battery cell 10, the surface formed by the length and height directions of the battery cell 10 is the large surface of the battery cell 10, and the surface formed by the width and height directions of the battery cell 10 is the side surface of the battery cell 10.

[0087] Here, the electrode assembly 2 is wound by a positive electrode sheet, a negative electrode sheet and a separator. The separator is used to separate the positive electrode sheet and the negative electrode sheet, and plays an insulating role for the positive electrode sheet and the negative electrode sheet.

[0088] The insulating film 1 is, for example, Mylar film, which is coated on the periphery of the electrode assembly 2 and is located between the electrode assembly 2 and the shell, and plays a role in sealing and protecting the electrode assembly 2. The Mylar film can effectively insulate the electrode assembly 2 and the shell 3 from each other, and avoid short circuit inside the battery cell 10. The shell 3 plays a role in protecting the electrode assembly 2 inside.

[0089] It is understandable that the insulating film 1 can also be equivalent to a heat insulating layer between the electrode assembly 2 and the shell 3, that is, it plays a role of heat insulation for the electrode assembly 2.

[0090] The insulating film 1 has a first thickness region and a second thickness region, and the thickness of the first thickness region is greater than that of the second thickness region. That is, the insulating film 1 has at least two regions with different thicknesses. In this way, the insulating film 1 can be arranged according to requirements.

[0091] The first thickness region is located in the region where the first surface of the electrode assembly 2 is located, that is, the thickness of the insulating film 1 covering at least part of the first surface of the electrode assembly 2 is greater than the thickness of the insulating film 1 covering the small surface of the electrode assembly 2 .

[0092] In the related art, after the battery cell is charged and discharged, the electrode assembly expands in the thickness direction, which easily causes the large surface of the electrode assembly to be squeezed and contacted with the outer shell, while the side of the electrode assembly is not easy to contact with the outer shell. Therefore, when thermal runaway occurs inside the electrode assembly, the temperature inside the electrode assembly rises sharply, and the large surface of the electrode assembly easily melts the insulating film, causing heat to be transferred to the large surface of the outer shell, and then to the adjacent battery cells, causing heat diffusion in the adjacent battery cells, resulting in fire and explosion.

[0093] The battery cell 10 provided in the embodiment of the present application includes an electrode assembly 2, a shell and an insulating film 1. The insulating film 1 is provided with a first thickness region and a second thickness region, and the thickness of the first thickness region is greater than the thickness of the second thickness region. The first thickness region is provided in the area where the first surface of the electrode assembly 2 is located, that is, the thickness of the insulating film 1 covering at least part of the first surface of the electrode assembly 2 is greater than the thickness of the insulating film 1 covering other surfaces of the electrode assembly 2 except the first surface. In this way, when the electrode assembly 2 is short-circuited, overcharged, or has internal thermal runaway, the rapid transfer of heat to the shell 3 can be improved, the thermal insulation protection effect of the insulating film 1 can be improved, and the reliability of the battery cell 10 can be improved.

[0094] In the related art, the insulating film of the electrode assembly is coated in a side overlapping manner, that is, the insulating film of the large surface of the electrode assembly is one layer, which is equivalent to the thermal insulation layer of the large surface of the electrode assembly being one layer of insulating film, and the insulating film of at least part of the side surface of the electrode assembly is two layers, which is equivalent to the thermal insulation layer of at least part of the side surface of the electrode assembly being two layers of insulating film.

[0095] In some embodiments, see Figures 4 to 6 The insulating film 1 is formed by folding the substrate 11. The insulating film 1 includes an overlapping region where the substrate 11 is overlapped. The overlapping region constitutes a first thickness region.

[0096] That is, the substrate 11 is formed into an insulating film 1 of a desired shape through steps such as folding and gluing. The substrate 11 is wound along the circumference of the electrode assembly. During the winding process, the tail of the substrate 11 exceeds the head of the substrate 11, so that the substrate 11 forms an overlapping area between the head and the tail, and the thickness of the overlapping area is twice the thickness of the substrate.

[0097] The insulating film 1 includes an overlapping region where the substrates 11 are overlapped, that is, the number of layers of the substrates 11 of the insulating film 1 in the overlapping region is at least two.

[0098] Here, the thickness of the substrates 11 is the same, and the thickness of the insulating film 1 in the overlapping region is increased by overlapping the substrates 11 .

[0099] In this embodiment, the insulating film 1 includes an overlapping area where the substrate 11 is overlapped, and the overlapping area constitutes a first thickness area, that is, the insulating film 1 in the area where the first surface of the electrode assembly 2 is located is at least two layers, that is, the thermal insulation layer in the area where the first surface of the electrode assembly 2 is located is at least two layers of insulating film 1. In this way, the thickness of the insulating film 1 in the area where the first surface of the electrode assembly 2 is located is greater than the thickness of the insulating film 1 on other surfaces, thereby increasing the thickness of the insulating film 1 between the first surface of the electrode assembly 2 and the outer shell 3, thereby improving the thermal insulation effect of the insulating film 1.

[0100] In some embodiments, the insulating film 1 includes a substrate 11 and a sprayed layer, and a portion of the substrate 11 is provided with the sprayed layer to form a first thickness region.

[0101] Here, an insulating spray coating is formed by spraying a ceramic coating on the substrate 11 corresponding to the first surface of the electrode assembly 2, thereby increasing the thickness of the insulating film 1 corresponding to the first surface of the electrode assembly 2 and improving the heat insulation effect of the insulating film 1.

[0102] In some embodiments, the insulating film 1 includes a substrate 11 and a coding resin, and a portion of the substrate 11 is provided with the coding resin to form a first thickness region.

[0103] Here, by providing a coding glue on the substrate 11 corresponding to the first surface of the electrode assembly 2, the thickness of the insulating film 1 corresponding to the first surface of the electrode assembly 2 is increased, thereby improving the heat insulation effect of the insulating film 1.

[0104] In some embodiments, the number of the electrode assembly 2 is one, and the two first surfaces of the electrode assembly 2 are both provided with a first thickness region.

[0105] In this embodiment, both first surfaces of the electrode assembly 2 are provided with a first thickness region, that is, the thickness of the insulating film 1 covering at least part of the two first surfaces of the electrode assembly 2 is greater than the thickness of the insulating film 1 covering other surfaces of the electrode assembly 2 except the first surface. In this way, the heat insulation protection effect of the insulating film 1 is further improved, and the reliability of the battery cell 10 is further improved.

[0106] Of course, in other embodiments, one of the first surfaces of the electrode assembly 2 may be provided with the first thickness region, and the other first surface may be provided with the first thickness region.

[0107] In some embodiments, the battery cell 10 includes a shell 3, an electrode assembly 2 is disposed in the shell 3, there are two electrode assemblies 2, the areas where the first surfaces of the two electrode assemblies 2 are opposite to each other are both provided with a first thickness area, and the areas where the first surfaces of the two electrode assemblies 2 are opposite to each other are not provided with a first thickness area.

[0108] Here, the large surfaces opposite to each other of the two electrode assemblies 2 are both provided with the first thickness region, and the large surfaces opposite to each other of the two electrode assemblies 2 are not provided with the first thickness region, which means that the large surfaces of the two electrode assemblies 2 close to the outer shell 3 are both provided with the first thickness region, and the large surfaces close to the other electrode assembly 2 are not provided with the first thickness region.

[0109] In this way, while improving the heat insulation protection effect of the insulating film 1, the space occupied by the insulating film 1 can also be reduced, which is beneficial to improving the performance of the battery.

[0110] It should be noted that the above methods can be implemented separately or simultaneously.

[0111] In some embodiments, see Figure 5 The length of the electrode assembly 2 is L0, and the dimension of the first thickness region along the length direction of the electrode assembly 2 is L1, wherein the ratio of L1 to L0 is in the range of 0.8-1, for example, 0.8, 0.85, 0.9, 0.95 or 1, etc.

[0112] By setting the ratio of the dimension of the first thickness region along the length direction of the electrode assembly 2 to the length of the electrode assembly 2 to 0.8-1, the insulating film 1 corresponding to the first surface of the electrode assembly 2 can have sufficient structural strength and heat insulation effect while not affecting the assembly of the battery cell 10 and maintaining the structural compactness and performance of the battery cell 10.

[0113] In some embodiments, see Figures 4 to 6 The insulating film 1 is formed by folding a substrate 11, and the thickness of the substrate 11 is 0.05 mm-0.3 mm.

[0114] For example, 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.1mm, 0.12mm, 0.13mm, 0.15mm, 0.18mm, 0.2mm, 0.22mm, 0.23mm, 0.25mm, 0.27mm, 0.29mm or 0.3mm, etc.

[0115] By setting the thickness of the substrate 11 to 0.05mm-0.3mm, and the thickness of the insulating film 1 covering at least a portion of the first surface of the electrode assembly 2 is greater than the thickness of the insulating film 1 covering other surfaces of the electrode assembly 2 except the first surface, on the one hand, the thickness of the insulating film 1 corresponding to the first surface of the electrode assembly 2 can be increased, so that it can better play a role in heat insulation protection. On the other hand, when the thickness of the insulating film 1 corresponding to the first surface of the electrode assembly 2 is the same, the thickness of the insulating film 1 corresponding to other surfaces of the electrode assembly 2 except the first surface can be reduced, thereby achieving a reduction in the cost of the battery 100.

[0116] In some embodiments, the insulating film 1 is formed by folding a substrate 11, the substrate 11 has a first wall thickness region and a second wall thickness region, the thickness of the first wall thickness region is greater than the thickness of the second wall thickness region, wherein the first wall thickness region is folded to form a first thickness region, and the second wall thickness region is folded to form a second thickness region.

[0117] The substrate 11 has a first wall thickness region and a second wall thickness region, and the thickness of the first wall thickness region is greater than that of the second wall thickness region. That is, the substrate 11 has at least two regions with different thicknesses. In this way, the substrate 11 can be arranged according to needs.

[0118] The thickness of the first wall thickness region is greater than the thickness of the second wall thickness region, wherein the first wall thickness region is folded to form a first thickness region, and the second wall thickness region is folded to form a second thickness region, that is, the thickness of the insulating film 1 covering at least a portion of the first surface of the electrode assembly 2 is greater than the thickness of the insulating film 1 covering other surfaces of the electrode assembly 2 except the first surface.

[0119] In this embodiment, by setting the substrate 11 to include two different wall thicknesses, a first wall thickness region and a second wall thickness region, and setting the first wall thickness region with a large wall thickness on the first surface of the electrode assembly 2, and setting the second wall thickness region with a small wall thickness on other surfaces of the electrode assembly 2 except the first surface, in this way, the thickness of the insulating film 1 corresponding to the first surface of the electrode assembly 2 is greater than the thickness of the insulating film 1 on other surfaces except the first surface, thereby increasing the thickness of the insulating film 1 between the first surface of the electrode assembly 2 and the outer shell 3, thereby improving the thermal insulation effect of the insulating film 1.

[0120] In some embodiments, the battery cell 10 includes a housing 3, and the electrode assembly 2 coated with the insulating film 1 is disposed in the housing 3, and the distance between the top of the insulating film 1 and the top cover 32 of the housing 3 is 0.1 mm-5 mm, for example, 0.1 mm, 0.3 mm, 0.5 mm, 0.8 mm, 1 mm, 1.5 mm, 1.8 mm, 2 mm, 2.3 mm, 2.8 mm, 3 mm, 3.5 mm, 3.8 mm, 4 mm, 4.5 mm, 4.8 mm or 5 mm, etc.

[0121] Exemplarily, the housing 3 includes a top cover 32 and a shell 31 , the shell 31 is provided with an opening, and the top cover 32 closes the opening to form a closed space for accommodating the electrode assembly 2 and substances such as electrolyte.

[0122] Here, the distance between the top of the insulating film 1 and the top cover 32 of the outer case 3 refers to the distance between the insulating film 1 and the top cover 32 in the height direction of the battery cell 10 .

[0123] Exemplarily, the battery cell 10 further includes a lower plastic, a top cover 32 closes the opening of the shell 31, the electrode assembly 2 is disposed in the shell 3, and the lower plastic is disposed between the top cover 32 and the electrode assembly 2. The lower plastic abuts against the electrode assembly 2 to achieve positioning of the electrode assembly 2. The insulating film 1 wraps around at least a portion of the electrode assembly 2 and the lower plastic to insulate and isolate the electrode assembly 2 from the shell 31.

[0124] Here, the insulating film 1 is connected to the lower plastic by ultrasonic welding or heat melting.

[0125] In this embodiment, by setting the distance between the top of the insulating film 1 and the top cover 32 of the shell 3 to 0.1mm-5mm, it is beneficial to achieve the connection between the insulating film 1 and the top cover 32 while minimizing the impact on the assembly of the top cover 32 to the shell 31.

[0126] In some embodiments, see Figures 4 to 6 The embodiment of the present application further provides an insulating film 1 , which is used as the battery cell 10 of any embodiment of the present application, and the insulating film 1 is used to cover the electrode assembly 2 of the battery cell 10 .

[0127] The insulating film 1 is provided with a first thickness region and a second thickness region, wherein the thickness of the first thickness region is greater than that of the second thickness region, and the first thickness region is provided on the first surface of the electrode assembly 2, that is, the thickness of the insulating film 1 covering at least a portion of the first surface of the electrode assembly 2 is greater than the thickness of the insulating film 1 covering other surfaces of the electrode assembly 2 except the first surface. In this way, when the electrode assembly 2 is short-circuited, overcharged, or has internal thermal runaway, the rapid transfer of heat to the outer casing 3 can be improved, thereby improving the thermal insulation protection effect of the insulating film 1 and thereby improving the reliability of the battery cell 10.

[0128] In some embodiments, please refer to Figures 4 to 6 The insulating film 1 is formed by folding a substrate 11 having a bottom covering wall 113, a first side covering wall 112 and a second side covering wall 111, wherein the area of ​​the second side covering wall 111 is greater than the area of ​​the first side covering wall 112; and when the substrate 11 is in an unfolded state, the bottom covering wall 113 is respectively connected to a first side covering wall 112 at both ends along the first direction, and each first side covering wall 112 is respectively connected to a second side covering wall 111 at both ends along the second direction, wherein the first direction intersects with the second direction.

[0129] The intersection of the first direction and the second direction means that the first direction and the second direction are not parallel. Exemplarily, the first direction and the second direction are perpendicular to each other.

[0130] Here, the first direction is a length direction of the battery cell 10 , and the second direction is a width direction of the battery cell 10 .

[0131] The two first side covering walls 112 are respectively connected to the two ends of the bottom covering wall 113 along the first direction, and each of the first side covering walls 112 is respectively connected to a second side covering wall 111 at both ends along the second direction, that is, when the substrate 11 is in the unfolded state, the substrate 11 includes four second side covering walls 111, and when the substrate 11 is in the wrapped state, the two second side covering walls 111 jointly cover the large surface of the electrode assembly 2, and the two second side covering walls 111 have an overlapping area, the overlapping area constitutes a first thickness area, and the area without overlapping of the second side covering walls 111 constitutes a second thickness area, the bottom covering wall 113 covers the bottom surface of the electrode assembly 2, and the two first side covering walls 112 respectively cover the two side surfaces of the electrode assembly 2.

[0132] The structural strength of the connection between the bottom covering wall 113, the first side covering wall 112 and the second side covering wall 111 is less than the structural strength of the bottom covering wall 113, the first side covering wall 112 and the second side covering wall 111. For example, by setting an indentation or forming a structural weakened area, it is beneficial to fold at the connection and improve assembly efficiency and reliability.

[0133] In this embodiment, when the substrate 11 is in a coated state, each first surface of the electrode assembly 2 is coated with two second side coating walls 111, and the two second side coating walls 111 have an overlapping area, and the overlapping area constitutes a first thickness area. That is to say, by setting the insulating film 1 to overlap at the large surface of the electrode assembly 2, the thickness of the insulating film 1 between the first surface of the electrode assembly 2 and the outer shell 3 is increased, thereby improving the thermal insulation effect of the insulating film 1.

[0134] It should be noted that data such as the length L0 of the electrode assembly 2, the dimension L1 of the first thickness region along the length direction of the electrode assembly 2, the thickness of the substrate 11, and the distance between the top of the insulating film 1 and the top cover 32 of the outer shell 3 can be obtained at room temperature through tests such as a high-precision thickness gauge and a vernier caliper.

[0135] The electrode terminal on the housing 3 is electrically connected to the electrode tab of the electrode assembly 2. For example, see Figure 4 The battery cell 10 is provided with an adapter 6, and the electrode terminal is indirectly connected to the electrode tab through the adapter 6.

[0136] For example, see Figure 4 The battery cell 10 includes a bottom support plate 5 , which is disposed in the housing 3 and located at the bottom of the electrode assembly 2 .

[0137] For example, see Figure 4 The battery cell 10 includes a blue film 4 , which is coated on the outer circumference of the housing 3 to insulate adjacent battery cells 10 .

[0138] In the description of the present application, the description with reference to the terms "in one embodiment", "in some embodiments", "in other embodiments", "in yet other embodiments", or "exemplary" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In the present application, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine the different embodiments or examples described in the present application and the features of the different embodiments or examples without contradiction.

[0139] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application are included in the protection scope of the present application.

Claims

1. A battery cell, characterized in that: include: An electrode assembly, the electrode assembly comprising a plurality of surfaces, the plurality of surfaces comprising a first surface, the first surface being a surface with the largest area among the plurality of surfaces; A shell, forming a receiving space for receiving the electrode assembly; An insulating film, which is coated on the periphery of the electrode assembly and is located between the electrode assembly and the shell, and has a first thickness region and a second thickness region, the thickness of the first thickness region is greater than the thickness of the second thickness region, wherein the first thickness region is located in the region where the first surface of the electrode assembly is located.

2. The battery cell according to claim 1, characterized in that: The insulating film is formed by folding a substrate, and the insulating film includes an overlapping region where the substrate is overlapped, and the overlapping region constitutes the first thickness region.

3. The battery cell according to claim 1, characterized in that: The length of the electrode assembly is L0, and the dimension of the first thickness region along the length direction of the electrode assembly is L1, wherein the ratio of L1 to L0 is in the range of 0.8-1.

4. The battery cell according to claim 1, characterized in that: The insulating film is formed by folding a substrate, and the thickness of the substrate is 0.05 mm-0.3 mm.

5. The battery cell according to claim 1, characterized in that: The insulating film is formed by folding a substrate, the substrate having a first wall thickness region and a second wall thickness region, the thickness of the first wall thickness region is greater than the thickness of the second wall thickness region, wherein the first wall thickness region is folded to form the first thickness region, and the second wall thickness region is folded to form the second thickness region.

6. The battery cell according to any one of claims 1 to 5, characterized in that: The battery cell comprises a shell, the electrode assembly covered with the insulating film is arranged in the shell, and the distance between the top of the insulating film and the top cover of the shell is 0.1 mm-5 mm.

7. The battery cell according to claim 1, characterized in that: The number of the electrode assembly is one, and the first thickness region is disposed in regions where the two first surfaces of the electrode assembly are located.

8. The battery cell according to claim 1, characterized in that: The battery cell includes a shell, the electrode assembly is arranged in the shell, the number of the electrode assemblies is two, the first surfaces of the two electrode assemblies opposite to each other are both provided with the first thickness region, and the first surfaces of the two electrode assemblies opposite to each other are not provided with the first thickness region.

9. The battery cell according to claim 1, characterized in that: The insulating film includes a substrate and a sprayed layer, and a partial area of ​​the substrate is provided with the sprayed layer to form the first thickness area.

10. The battery cell according to claim 1, characterized in that: The insulating film includes a substrate and a coding glue, and a partial area of ​​the substrate is provided with the coding glue to form the first thickness area.

11. An insulating film, characterized in that: The insulating film is used as the battery cell according to any one of claims 1 to 6, and the insulating film is used to cover an electrode assembly of the battery cell.

12. The insulating film according to claim 11, characterized in that The insulating film is formed by folding a substrate having a bottom covering wall, a first side covering wall and a second side covering wall, wherein the area of ​​the second side covering wall is greater than the area of ​​the first side covering wall; and when the substrate is in an unfolded state, the bottom covering wall is respectively connected to one of the first side covering walls at both ends along the first direction, and each of the first side covering walls is respectively connected to one of the second side covering walls at both ends along the second direction, wherein the first direction intersects with the second direction.

13. A battery, characterized in that: The invention comprises at least one battery cell according to any one of claims 1 to 12.

14. An electrical device, characterized in that: A battery according to claim 13, for providing electrical energy.

Images