Battery monomer, battery device and electric equipment

Abstract

The utility model relates to the technical field of battery production, in particular to a battery monomer, a battery device and electric equipment. The battery monomer comprises a shell and an insulating film, the insulating film comprises a film layer unit, the film layer unit comprises a base material layer, an expansion layer, a first adhesive layer and a second adhesive layer which are stacked, and the expansion layer covers at least part of the surface of the base material layer; the base material layer and the expansion layer are connected through the first adhesive layer, and one of the base material layer and the expansion layer is connected with the shell through the second adhesive layer. According to the battery monomer provided by the embodiment of the invention, when the shell of the battery monomer is punctured, the leaked electrolyte can be absorbed by the expansion layer, so that the probability that the electrolyte leaks into the air can be reduced.

Description

Technical Field

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

[0002] This section provides only background information relevant to this disclosure and is not necessarily prior art.

[0003] With the increasing maturity of new energy technologies, new energy vehicles and other electrical equipment are gradually entering the public eye. The core technology of new energy vehicles lies in the battery device, and the safety and stability of the battery device directly determine the performance of the entire vehicle.

[0004] Battery devices typically consist of multiple individual battery cells, each including a casing and an insulating film on the outside of the casing. When the casing of a battery cell is punctured, electrolyte leakage into the air is likely to occur. Utility Model Content

[0005] In view of the above problems, this application provides a battery cell, a battery device, and an electrical device, which solves the problem in the prior art that electrolyte leakage into the air is easy when the casing of the battery cell is punctured.

[0006] A first aspect of the embodiments of this application provides a battery cell, the battery cell including a housing and an insulating film, the insulating film including a film layer unit, the film layer unit including a substrate layer, an expansion layer, a first adhesive layer and a second adhesive layer stacked thereon, wherein the expansion layer covers at least a portion of the surface of the substrate layer; the substrate layer and the expansion layer are connected by the first adhesive layer, and one of the substrate layer and the expansion layer is connected to the housing by the second adhesive layer.

[0007] According to an embodiment of this application, in a battery cell, the insulating film includes a film layer unit, wherein the film layer unit includes a substrate layer, an expansion layer, a first adhesive layer, and a second adhesive layer stacked together, wherein the expansion layer covers at least a portion of the surface of the substrate layer; the substrate layer and the expansion layer are connected by the first adhesive layer, and one of the substrate layer and the expansion layer is connected to the casing by the second adhesive layer. In the event that the casing of the battery cell is punctured, the leaked electrolyte can be absorbed by the expansion layer, thereby reducing the probability of electrolyte leakage into the air.

[0008] In some embodiments of this application, the expanded layer includes one of a oriented polystyrene layer, a biaxially oriented polypropylene layer, a biaxially oriented nylon layer, and a biaxially oriented polyester layer.

[0009] The embodiments of this application include an expansion layer comprising one of a oriented polystyrene layer, a biaxially oriented polypropylene layer, a biaxially oriented nylon layer, and a biaxially oriented polyester layer. This allows the absorption of electrolyte using oriented polystyrene, biaxially oriented polypropylene, biaxially oriented nylon, or biaxially oriented polyester materials, thereby reducing the probability of spontaneous combustion caused by leaked electrolyte coming into contact with air.

[0010] In some embodiments of this application, the substrate layer includes one of a polyethylene terephthalate layer and a polypropylene layer.

[0011] The embodiments of this application include a substrate layer comprising either a polyethylene terephthalate layer or a polypropylene layer. This allows the use of either polyethylene terephthalate or polypropylene material in the electrolyte to provide enhanced strength and insulation properties, thereby achieving insulation between two adjacent battery cells.

[0012] In some embodiments of this application, the number of expansion layers is at least two, and the two expansion layers are spaced apart along the length direction of the substrate layer.

[0013] The embodiments of this application, by having at least two expansion layers spaced apart along the length of the substrate layer, still enable the absorption of electrolyte through the expansion layers, and can reduce the cost of the insulating film, thereby reducing the production cost of the battery cell.

[0014] In some embodiments of this application, the shell has a rectangular structure, the rectangular structure includes multiple surfaces, the multiple surfaces include a first surface, the first surface is the surface with the largest area among the multiple surfaces; the first surface and an expansion layer are disposed opposite to each other.

[0015] In the embodiments of this application, by setting a first surface and an expansion layer opposite to each other, wherein the first surface is the surface with the largest area among the multiple surfaces of the shell, the expansion layer can be set opposite to the first surface with the largest area of ​​the shell, thereby achieving the absorption of electrolyte near the first surface with the largest area of ​​the shell.

[0016] In some embodiments of this application, there are two first surfaces, and the two first surfaces are arranged opposite to each other; the two expansion layers and the two first surfaces are respectively arranged opposite to each other.

[0017] The embodiments of this application, by setting the number of first surfaces to two, with the two first surfaces arranged opposite each other, and the two expansion layers and the two first surfaces arranged opposite each other, can enable the two expansion layers to absorb the electrolyte near the two first surfaces respectively, thereby absorbing the electrolyte flowing out of the casing and reducing the probability of electrolyte leakage to the outside of the battery cell.

[0018] In some embodiments of this application, the thickness of the expansion layer is T1, and the thickness of the substrate layer is T2, wherein the ratio of T1 to T2 ranges from 0.5 to 10.

[0019] In the embodiments of this application, by setting the ratio of the thickness T1 of the expansion layer to the thickness T2 of the substrate layer to be in the range of 0.5 to 10, the insulating film can absorb the electrolyte overflowing from the shell and can have strength and insulation properties.

[0020] In some embodiments of this application, the ratio of T1 to T2 ranges from 1 to 5.

[0021] In the embodiments of this application, by setting the ratio of the thickness T1 of the expansion layer to the thickness T2 of the substrate layer to be in the range of 1 to 5, the insulating film can absorb the electrolyte overflowing from the shell and can give the insulating film strength and insulation properties.

[0022] In some embodiments of this application, the total thickness of the insulating film is in the range of 0.05 mm to 0.5 mm.

[0023] In the embodiments of this application, by keeping the total thickness of the insulating film in the range of 0.05 mm to 0.5 mm, the insulating film can absorb leaked electrolyte and has insulating properties.

[0024] In some embodiments of this application, the number of film layer units is at least two, and at least two film layer units are stacked.

[0025] The embodiments of this application, by having at least two membrane units stacked together, enable the absorption of electrolyte through the expansion layer in each membrane unit, thereby improving the absorption efficiency of electrolyte. In addition, the substrate layer in each membrane unit can enhance the insulation performance between two adjacent battery cells.

[0026] A second aspect of the embodiments of this application provides a battery device comprising the battery cells mentioned in the above embodiments.

[0027] A third aspect of the embodiments of this application provides an electrical device that includes the battery cell mentioned in the above embodiments, the battery cell being used to supply power to the electrical device.

[0028] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0029] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0030] Figure 1 This is a schematic diagram of the structure of a battery device provided in some embodiments of this application;

[0031] Figure 2 This is a schematic diagram of the structure of an electrical device provided in some embodiments of this application;

[0032] Figure 3 for Figure 1 A schematic diagram of the exploded structure of a single battery cell in the battery device shown;

[0033] Figure 4 for Figure 3 A schematic diagram of the cross-section of the insulating film of the battery cell shown;

[0034] Figure 5 for Figure 4 Another structural schematic diagram of the cross-section of the insulating film of the battery cell shown;

[0035] Figure 6 for Figure 4 Another structural schematic diagram of the cross-section of the insulating film of the battery cell shown;

[0036] Figure 7 for Figure 4 The schematic diagram of the three-dimensional structure of the insulating film of the battery cell shown (the first adhesive layer and the second adhesive layer are not shown);

[0037] Figure 8 for Figure 7 The diagram shows the structure of a battery cell with the insulating film in an unfolded state.

[0038] Figure 9 for Figure 4 Another three-dimensional structural diagram of the insulating film of the battery cell shown (the first adhesive layer and the second adhesive layer are not shown);

[0039] Figure 10 for Figure 9 The diagram shows the structure of a battery cell with the insulating film in an unfolded state.

[0040] The attached figures are labeled as follows:

[0041] 100. Battery device; 200. Electrical equipment; 300. Controller; 400. Motor;

[0042] 10. Battery cell; 11. Top cover assembly; 12. Electrode assembly; 13. Housing; 131. First surface; 132. Second surface; 14. Insulating film; 141. Film layer unit; 1411. Substrate layer; 1412. Expansion layer; 1413. First adhesive layer; 1414. Second adhesive layer;

[0043] 20. Container assembly; 21. First container; 22. Second container; 23. Storage space;

[0044] T1, the thickness of the expansion layer;

[0045] T2, thickness of the substrate layer;

[0046] T, the total thickness of the insulating film;

[0047] XX, the length direction of the substrate layer. Detailed Implementation

[0048] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0050] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0051] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0052] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0053] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0054] In the description of the embodiments of this application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0055] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0056] Currently, judging from market trends, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely applied in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of battery device applications, market demand is also constantly increasing.

[0057] The battery devices described in this application can be used, but are not limited to, in electrical equipment such as vehicles, ships, or aircraft. Such electrical equipment can be composed of battery cells and battery devices as described in this application.

[0058] In this application embodiment, the electrical devices using battery devices as power sources can be, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Among them, electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0059] It should be understood that the technical solutions described in the embodiments of this application are not limited to the battery devices and electrical equipment described above, but can also be applied to all batteries including housings and electrical equipment using batteries.

[0060] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells connected in series, parallel, or mixed connections via a busbar.

[0061] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells.

[0062] As an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form an independent module. As another example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0063] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cells housed within the housing.

[0064] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0065] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0066] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first enclosure may be a top cover or a bottom plate.

[0067] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0068] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0069] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly consists of a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrodes. The positive electrode includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector. Current collectors without the positive active material layer protrude beyond those with the coating. These uncoated current collectors are stacked together to form the positive electrode tab. Taking a lithium-ion battery as an example, the positive current collector can be made of aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative current collector. Current collectors without the negative active material layer protrude beyond those with the coating. These uncoated current collectors are stacked together to form the negative electrode tab. The negative current collector can be made of copper, and the negative active material can be carbon or silicon, etc. The separator can be made of PP (polypropylene) or PE (polyethylene), etc. Furthermore, the electrode assembly can be a wound structure or a stacked structure; the embodiments of this application are not limited to these.

[0070] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use individual battery cells, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft.

[0071] A battery device typically consists of multiple battery cells. Each battery cell includes a casing and an insulating film located on the outside of the casing. This insulating film, also called a blue film, serves an insulating function. When the casing of a battery cell is punctured, electrolyte leakage into the air can easily occur.

[0072] To address this problem, embodiments of this application propose a battery cell comprising a casing and an insulating film. The insulating film includes film layer units, each comprising a substrate layer, an expansion layer, a first adhesive layer, and a second adhesive layer stacked together. The expansion layer covers at least a portion of the surface of the substrate layer. The substrate layer and the expansion layer are connected by the first adhesive layer, and one of the substrate layer and the expansion layer is connected to the casing via the second adhesive layer. According to embodiments of this application, by including film layer units in the insulating film, wherein the film layer units comprise a substrate layer, an expansion layer, a first adhesive layer, and a second adhesive layer stacked together, wherein the expansion layer covers at least a portion of the surface of the substrate layer; and the substrate layer and the expansion layer are connected by the first adhesive layer, and one of the substrate layer and the expansion layer is connected to the casing via the second adhesive layer, the leaked electrolyte can be absorbed by the expansion layer when the casing of the battery cell is punctured, thereby reducing the probability of electrolyte leakage into the air.

[0073] The battery cells in the embodiments of this application can be used in electrical equipment such as vehicles, or installed in products such as energy storage devices.

[0074] The structures in the embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0075] Please refer to Figure 2 , Figure 2 This is a schematic diagram of the structure of an electrical device 200 provided in some embodiments of this application. The electrical device 200 can be a vehicle, which can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 is installed inside the vehicle, and the battery device 100 can be located at the bottom, front, or rear of the vehicle. The battery device 100 can be used to power the vehicle; for example, the battery device 100 can serve as the vehicle's operating power source. The electrical device 200 may also include a controller 300 and a motor 400. The controller 300 is used to control the battery device 100 to supply power to the motor 400, for example, to meet the power needs of the vehicle during starting, navigation, and driving.

[0076] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the electrical equipment 200, but also as the driving power source for the electrical equipment 200, replacing or partially replacing fuel oil or natural gas to provide driving power for the electrical equipment 200.

[0077] like Figure 1As shown, the battery device 100 mentioned in the embodiments of this application may include one or more battery cell assemblies 10 for providing voltage and capacity. A battery cell assembly 10 may include multiple battery cells 10, which are connected in series, parallel, or mixed connections via a busbar.

[0078] In some embodiments, the battery cell assembly is typically formed by arranging multiple battery cells 10.

[0079] As an example, the battery cell 10 assembly can be a battery module, which is formed by arranging and fixing multiple battery cells 10 together to form an independent module. As an example, the battery module can be formed by bundling multiple battery cells 10 together with cable ties.

[0080] In some embodiments, such as Figure 1 As shown, Figure 1 The present invention provides a schematic diagram of the structure of a battery device 100 according to some embodiments of the present application. The battery device 100 may be a battery pack, which includes a housing assembly 20 and one or more battery cell 10 assemblies, with the battery cell 10 assemblies housed in the housing assembly 20.

[0081] As an example, such as Figure 1 As shown, the housing assembly 20 may include a first housing 21 and a second housing 22. The first housing 21 and the second housing 22 are fastened together, forming a closed receiving space 23 inside the housing assembly 20 to house the individual battery cells 10. Here, "closed" refers to covering or closing, which can be either sealed or unsealed. The first housing 21 is a top cover, and the second housing 22 is a bottom plate. Alternatively, the first housing 21 can be a bottom plate, and the second housing 22 can be a top cover.

[0082] like Figure 3 and Figure 4 As shown, the battery cell 10 includes a housing 13 and an insulating film 14. The insulating film 14 includes a film layer unit 141, which includes a substrate layer 1411, an expansion layer 1412, a first adhesive layer 1413, and a second adhesive layer 1414 stacked together. The expansion layer 1412 covers at least a portion of the surface of the substrate layer 1411. The substrate layer 1411 and the expansion layer 1412 are connected by the first adhesive layer 1413, and one of the substrate layer 1411 and the expansion layer 1412 is connected to the housing 13 by the second adhesive layer 1414.

[0083] It should be noted that the expansion layer 1412 covering at least a portion of the surface of the substrate layer 1411 can be either covering the entire surface of the substrate layer 1411 or only covering a portion of the surface of the substrate layer 1411. The first adhesive layer 1413 and the second adhesive layer 1414 both serve an adhesive function. Specifically, the first adhesive layer 1413 can connect the substrate layer 1411 and the expansion layer 1412, and the second adhesive layer 1414 can connect the substrate layer 1411 and the shell 13, or the second adhesive layer 1414 can connect the expansion layer 1412 and the shell 13.

[0084] According to an embodiment of this application, the battery cell 10 includes an insulating film 14 comprising a film layer unit 141, wherein the film layer unit 141 includes a substrate layer 1411, an expansion layer 1412, a first adhesive layer 1413, and a second adhesive layer 1414 stacked together, wherein the expansion layer 1412 covers at least a portion of the surface of the substrate layer 1411; the substrate layer 1411 and the expansion layer 1412 are connected by the first adhesive layer 1413, and one of the substrate layer 1411 and the expansion layer 1412 is connected to the housing 13 by the second adhesive layer 1414. In the event that the housing 13 of the battery cell 10 is punctured, the leaked electrolyte can be absorbed by the expansion layer 1412, thereby reducing the probability of electrolyte leakage into the air.

[0085] Optionally, such as Figure 3 As shown, the battery cell 10 also includes a top cover assembly 11 and an electrode assembly 12, wherein the electrode assembly 12 is located inside the housing 13, and the top cover assembly 11 is located at the upper end of the housing 13 and connected to the housing 13.

[0086] The top cover assembly 11 includes a top cover plate and electrode terminals. The top cover plate is disposed on the housing 13 and covers the opening of the housing 13, thereby sealing the electrode assembly 12 inside the housing 13. The top cover plate may be a metal plate and is connected to the housing 13 by welding.

[0087] The electrode assembly 12 is the core component for the rechargeable battery to achieve its charging and discharging functions. The electrode assembly 12 includes a positive electrode, a negative electrode, and a separator, with the separator separating the positive and negative electrode. The positive electrode includes a positive current collector and a positive active material layer coated on the surface of the positive current collector. The positive current collector can be aluminum foil, and the positive active material layer includes ternary materials, lithium manganese oxide, or lithium iron phosphate. The negative electrode includes a negative current collector and a negative active material layer coated on the surface of the negative current collector. The negative current collector can be copper foil, and the negative active material layer includes graphite or silicon.

[0088] The electrode assembly 12 can be a wound structure. Specifically, there is one positive electrode and one negative electrode, and both the positive and negative electrode are strip-shaped structures. The positive electrode, the separator, and the negative electrode are stacked in sequence and wound two or more times to form the electrode assembly 12. In the preparation of the electrode assembly 12, the electrode assembly 12 can be first wound into a hollow cylindrical structure, and then flattened into a flat shape.

[0089] Alternatively, the electrode assembly 12 can also be a stacked structure. Specifically, multiple positive electrode sheets and multiple negative electrode sheets are provided, with the multiple positive and negative electrode sheets stacked alternately, and a separator separating the positive and negative electrode sheets.

[0090] In some embodiments of this application, such as Figures 4 to 10 As shown, the expansion layer 1412 includes one of the following: oriented polystyrene layer, biaxially oriented polypropylene layer, biaxially oriented nylon layer, and biaxially oriented polyester layer.

[0091] Specifically, the expansion layer 1412 includes an oriented polystyrene layer, which can be made of oriented polystyrene (OPS) material. The expansion layer 1412 can be a thin film structure made of oriented polystyrene through an oriented stretching process.

[0092] Specifically, the expansion layer 1412 includes a biaxially oriented polypropylene layer, which can be made of biaxially oriented polypropylene (BOPP) material. The molten polypropylene is first made into a sheet or thick film by passing the molten polymer through a narrow die head, then stretched in a dedicated stretching machine, and then made into a film by appropriate cooling or heat treatment or special processing (such as corona treatment, coating, etc.).

[0093] Specifically, the expansion layer 1412 includes a biaxially oriented nylon layer, which may be made of biaxially oriented nylon material.

[0094] Specifically, the expansion layer 1412 includes a biaxially oriented polyester layer, which may be made of biaxially oriented polyester material.

[0095] In the embodiments of this application, by including one of the following in the expansion layer 1412: oriented polystyrene layer, biaxially oriented polypropylene layer, biaxially oriented nylon layer, and biaxially oriented polyester layer, the electrolyte can be absorbed by the oriented polystyrene material, biaxially oriented polypropylene material, biaxially oriented nylon material, or biaxially oriented polyester material, thereby reducing the probability of spontaneous combustion caused by the leaked electrolyte coming into contact with air.

[0096] In some embodiments of this application, the substrate layer 1411 includes one of a polyethylene terephthalate layer and a polypropylene layer.

[0097] Specifically, the substrate layer 1411 includes a polyethylene terephthalate layer, which can be made of polyethylene terephthalate (PET) material. It has good strength and toughness and good processing performance, making it easy to process into a film or sheet structure.

[0098] Specifically, the substrate layer 1411 includes a polypropylene layer, which may be made of polypropylene material, which has good heat resistance, chemical resistance, impact resistance and mechanical strength, and is inexpensive.

[0099] The embodiments of this application include a polyethylene terephthalate layer and a polypropylene layer in the substrate layer 1411. The polyethylene terephthalate material or the polypropylene material can be used to provide strength and insulation properties in the electrolyte to achieve insulation between two adjacent battery cells 10.

[0100] In some embodiments of this application, such as Figure 7 and Figure 8 As shown, there are at least two expansion layers 1412, and the two expansion layers 1412 are spaced apart along the length direction of the substrate layer 1411.

[0101] Wherein, the length direction of the substrate layer 1411 is Figure 8 In the XX direction, Figure 8 In this process, there are two expansion layers 1412. Considering that the insulating film 14 is usually in a rolled structure, each insulating film 14 is provided with multiple expansion layers 1412, and the multiple expansion layers 1412 are spaced apart along the length direction of the substrate layer 1411. Each battery cell 10 is provided with two expansion layers 1412.

[0102] The embodiments of this application, by having at least two expansion layers 1412, and by having the two expansion layers 1412 spaced apart along the length of the substrate layer 1411, still enable the absorption of electrolyte through the expansion layers 1412, and reduce the cost of the insulating film 14, thereby reducing the production cost of the battery cell 10.

[0103] In some embodiments of this application, such as Figure 3 As shown, the shell 13 has a rectangular structure, which includes multiple surfaces, including a first surface 131, which is the surface with the largest area among the multiple surfaces; the first surface 131 and an expansion layer 1412 are disposed opposite to each other.

[0104] Optionally, the rectangular structure further includes a second surface 132, wherein the second surface 132 is connected to the first surface 131, and there are two second surfaces 132 and two first surfaces 131, forming a rectangular ring structure with the two first surfaces 131 and the two second surfaces 132.

[0105] Here, the first surface 131 and an expansion layer 1412 are arranged opposite to each other. The first surface 131 can be bonded to an expansion layer 1412, or the first surface 131 can be bonded to a substrate layer 1411 corresponding to an expansion layer 1412.

[0106] In the embodiments of this application, by setting a first surface 131 and an expansion layer 1412 opposite to each other, wherein the first surface 131 is the surface with the largest area among the multiple surfaces of the housing 13, the expansion layer 1412 can be set opposite to the first surface 131 with the largest area of ​​the housing 13, thereby achieving the absorption of electrolyte near the first surface 131 with the largest area of ​​the housing 13.

[0107] Specifically, there are two first surfaces 131, and the two first surfaces 131 are arranged opposite to each other; the two expansion layers 1412 and the two first surfaces 131 are respectively arranged opposite to each other. The two first surfaces 131 are arranged parallel to each other. Here, the first surface 131 refers to the surface with the largest area on the outer surface of the shell 13. The two first surfaces 131 and the two expansion layers 1412 are arranged opposite to each other. It is possible that one first surface 131 is bonded to one expansion layer 1412 and the other first surface 131 is bonded to another expansion layer 1412, or one first surface 131 is bonded to the substrate layer 1411 corresponding to one expansion layer 1412 and the other first surface 131 is bonded to another expansion layer 1412, or the other first surface 131 is bonded to the substrate layer 1411 corresponding to the other expansion layer 1412.

[0108] Alternatively, each battery cell 10 may also have three expansion layers 1412, wherein two expansion layers 1412 are disposed opposite to two first surfaces 131, and the third expansion layer 1412 is disposed opposite to a second surface 132. Alternatively, each battery cell 10 may also have four expansion layers 1412, wherein two expansion layers 1412 are disposed opposite to two first surfaces 131, and the other two expansion layers 1412 are disposed opposite to two second surfaces 132.

[0109] In the embodiments of this application, by setting the number of first surfaces 131 to two, and the two first surfaces 131 being arranged opposite to each other, and the two expansion layers 1412 and the two first surfaces 131 being arranged opposite to each other, the two expansion layers 1412 can absorb the electrolyte near the two first surfaces 131 respectively, thereby absorbing the electrolyte flowing out of the casing 13 and reducing the probability of electrolyte leakage to the outside of the battery cell 10.

[0110] In some embodiments, such as Figure 9 and Figure 10 As shown, there is one expansion layer 1412, and the expansion layer 1412 is a continuous structure along the length direction of the substrate layer 1411. At this time, the two first surfaces 131 and the two second surfaces 132 are all provided with expansion layers 1412, which can play a better role in absorbing electrolyte.

[0111] In some embodiments of this application, such as Figure 4 As shown, the thickness of the expansion layer 1412 is T1, and the thickness of the substrate layer 1411 is T2. The ratio of T1 to T2 ranges from 0.5 to 10, such as a ratio of 1, 2, 3, 4, 5, 6, or 7.

[0112] In the embodiments of this application, by setting the ratio of the thickness T1 of the expansion layer 1412 to the thickness T2 of the substrate layer 1411 to be in the range of 0.5 to 10, the insulating film 14 can absorb the electrolyte overflowing from the housing 13 and can give the insulating film 14 strength and insulation properties.

[0113] In some embodiments of this application, the ratio of T1 to T2 ranges from 1 to 5, such as 1.5, 2.5, 3.3 or 4.5.

[0114] In the embodiments of this application, by setting the ratio of the thickness T1 of the expansion layer 1412 to the thickness T2 of the substrate layer 1411 to a range of 1 to 5, the insulating film 14 can absorb the electrolyte overflowing from the housing 13 and can give the insulating film 14 strength and insulation properties.

[0115] In some embodiments of this application, the total thickness of the insulating film 14 is T, which is in the range of 0.05 mm to 0.5 mm. For example, the total thickness of the insulating film 14 can be 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, or 0.5 mm, etc. The thicknesses of the first adhesive layer 1413 and the second adhesive layer 1414 are relatively thin, and ordinary thicknesses can be used. The thicknesses of the expansion layer 1412 and the substrate layer 1411 can be determined based on the thickness ratio between the expansion layer 1412 and the substrate layer 1411.

[0116] In the embodiments of this application, by making the total thickness of the insulating film 14 in the range of 0.05 mm to 0.5 mm, the insulating film 14 can absorb the leaked electrolyte and has insulating properties.

[0117] In some embodiments of this application, such as Figure 6 As shown, the number of membrane units 141 is at least two, and at least two membrane units 141 are stacked. Figure 6 In this process, there are two membrane units 141, and the two membrane units 141 are arranged in a stacked manner.

[0118] Alternatively, the number of membrane units 141 can be three, four or more, and the multiple membrane units 141 can also be arranged in a stacked structure.

[0119] It should be added that the film layer unit 141 can be either an expansion layer 1412 connected to the housing 13, or a substrate layer 1411 connected to the housing 13. The stacking order of the expansion layer 1412 and the substrate layer 1411 in each film layer unit 141 can be the same or different. Figure 6 In the two film layer units 141, the stacking order of the first adhesive layer 1413, the second adhesive layer 1414, the expansion layer 1412, and the substrate layer 1411 is consistent. Alternatively, the order of the first adhesive layer 1413, the second adhesive layer 1414, the expansion layer 1412, and the substrate layer 1411 in the two film layer units 141 can be set to different structures, which can also achieve the effect of absorbing the electrolyte overflowing from the shell 13.

[0120] In the embodiments of this application, by having at least two membrane units 141 stacked together, the electrolyte can be absorbed through the expansion layer 1412 in each membrane unit 141, thereby improving the absorption efficiency of the electrolyte. In addition, the substrate layer 1411 in each membrane unit 141 can enhance the insulation performance between two adjacent battery cells 10.

[0121] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application.

[0122] A first aspect of the embodiments of this application provides a battery cell 10, which includes a housing 13 and an insulating film 14. The insulating film 14 includes a film layer unit 141, which includes a substrate layer 1411, an expansion layer 1412, a first adhesive layer 1413, and a second adhesive layer 1414 stacked together. The expansion layer 1412 covers at least a portion of the surface of the substrate layer 1411. The substrate layer 1411 and the expansion layer 1412 are connected by the first adhesive layer 1413, and one of the substrate layer 1411 and the expansion layer 1412 is connected to the housing 13 by the second adhesive layer 1414. Further, the expansion layer 1412 includes one of an oriented polystyrene layer, a biaxially oriented polypropylene layer, a biaxially oriented nylon layer, and a biaxially oriented polyester layer. Further, the substrate layer 1411 includes one of a polyethylene terephthalate layer and a polypropylene layer. Further, the number of expansion layers 1412 is at least two, and the two expansion layers 1412 are spaced apart along the length direction of the substrate layer 1411. Further, the housing 13 has a rectangular structure, the rectangular structure includes multiple surfaces, including a first surface 131, which is the surface with the largest area among the multiple surfaces; the first surface 131 and an expansion layer 1412 are disposed opposite to each other. Further, the number of first surfaces 131 is two, and the two first surfaces 131 are disposed opposite to each other; the two expansion layers 1412 and the two first surfaces 131 are respectively disposed opposite to each other. Further, the thickness of the expansion layer 1412 is T1, and the thickness of the substrate layer 1411 is T2, wherein the ratio of T1 to T2 ranges from 0.5 to 10. Further, the ratio of T1 to T2 ranges from 1 to 5. Further, the total thickness of the insulating film 14 is in the range of 0.05 mm to 0.5 mm. Furthermore, the number of membrane units 141 is at least two, and at least two membrane units 141 are stacked.

[0123] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A battery cell, characterized in that, include: case; as well as An insulating film, the insulating film comprising a film layer unit, the film layer unit comprising a substrate layer, an expansion layer, a first adhesive layer and a second adhesive layer stacked thereon, wherein the expansion layer covers at least a portion of the surface of the substrate layer; The substrate layer and the expansion layer are connected by the first adhesive layer, and one of the substrate layer and the expansion layer is connected to the housing by the second adhesive layer.

2. The battery cell as described in claim 1, characterized in that, The expansion layer includes one of the following: oriented polystyrene layer, biaxially oriented polypropylene layer, biaxially oriented nylon layer, and biaxially oriented polyester layer.

3. The battery cell as described in claim 1, characterized in that, The substrate layer includes one of a polyethylene terephthalate layer and a polypropylene layer.

4. The battery cell as described in claim 1, characterized in that, The number of expansion layers is at least two, and the two expansion layers are spaced apart along the length direction of the substrate layer.

5. The battery cell as described in claim 4, characterized in that, The shell has a rectangular structure, which includes multiple surfaces, including a first surface, which is the surface with the largest area among the multiple surfaces. The first surface and the expansion layer are disposed opposite to each other.

6. The battery cell as described in claim 5, characterized in that, The number of the first surfaces is two, and the two first surfaces are arranged opposite to each other; The two expansion layers and the two first surfaces are respectively disposed opposite to each other.

7. The battery cell as described in claim 1, characterized in that, The thickness of the expansion layer is T1, and the thickness of the substrate layer is T2, wherein the ratio of T1 to T2 ranges from 0.5 to 10.

8. The battery cell as described in claim 7, characterized in that, The ratio of T1 to T2 ranges from 1 to 5.

9. The battery cell according to any one of claims 1 to 8, characterized in that, The total thickness of the insulating film is in the range of 0.05 mm to 0.5 mm.

10. The battery cell according to any one of claims 1 to 8, characterized in that, The number of the membrane units is at least two, and at least two of the membrane units are stacked.

11. A battery device, characterized in that, Includes the battery cell as described in any one of claims 1 to 10.

12. An electrical appliance, characterized in that, Includes a battery cell as described in any one of claims 1 to 10, the battery cell being used to supply power to the electrical device.

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