Novel power battery wrapping film and power battery thereof

Abstract

The utility model discloses a novel power battery wrapping film and a power battery thereof, the wrapping film comprises a base material layer, an adhesive layer and a release layer, the base material layer comprises a first PET layer, a first adhesive layer and a functional layer, and the first PET layer, the first adhesive layer, the functional layer, the adhesive layer and the release layer are compounded in sequence; wherein the functional layer is provided with a plurality of holes at intervals, the holes extend in the thickness direction of the functional layer and penetrate through the functional layer, and the functional layer is formed by forming a film from at least one of glass fibers, non-woven fabrics, bamboo fibers and glass powder. In the scheme of the utility model, by arranging the functional layer which has a porous structure and is formed by forming a film from any material of glass fiber, non-woven fabric, bamboo fiber and glass powder, the flexibility of the wrapping film can be obviously improved, the phenomenon of natural upwarp of corners after wrapping is solved, and the stability among the layers of the wrapping film is enhanced; therefore, the wrapping film is not easy to generate problems such as interlayer displacement and stripping, and is not easy to be broken down under high voltage, so that the wrapping film is not easy to generate phenomena such as excessive deformation, upwarp or crack and the like.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of adhesive, especially to a novel power battery wrapping film and a power battery with the same. BACKGROUND

[0002] In recent years, with the popularity of new energy vehicles, new energy vehicles are increasingly favored by people, and thus the requirements for power batteries as the "heart" of new energy vehicles are also increasingly high. During the manufacturing, assembly and use of power batteries, wrapping films are needed to protect the surface of the batteries, play a protective and fixing role in the batteries, and improve the use safety and life of the batteries.

[0003] At present, most of the wrapping films used for the outer packaging of power batteries are composite materials. The multi-layer composite material needs to be coated, dried and compounded multiple times during preparation, and the operation process is complex. The multi-layer structure formed thereby has problems such as poor structural compatibility, interlayer displacement and peeling. In addition, the power battery wrapping film also requires high temperature resistance, voltage resistance, good flexibility, high adhesion and other properties to avoid displacement, warping or deformation during use, but in realizing these properties, the traditional method mainly improves the film material, adhesive and preparation process of the wrapping film (for example, a power battery wrapping film disclosed in Chinese patent No. CN115011266B and a power battery external wrapping film and its preparation method disclosed in Chinese patent application No. CN105907104A), resulting in low preparation yield, high product cost and poor performance stability of the wrapping film, which is not conducive to the development of the power battery wrapping film industry.

[0004] Therefore, it is of beneficial value and significance to develop a power battery wrapping film with high flexibility, strong inter-film stability and good voltage resistance performance. UTILITY MODEL CONTENTS

[0005] In order to overcome the technical problems of poor flexibility, inter-film stability and voltage resistance performance of the existing power battery wrapping film, the utility model provides a novel power battery wrapping film and a power battery.

[0006] The utility model adopts the technical scheme that:

[0007] A novel power battery wrapping film is provided, which comprises:

[0008] A base material layer, an adhesive layer and a release layer, the base material layer comprises a first PET layer, a first adhesive layer and a functional layer, the first PET layer, the first adhesive layer, the functional layer, the adhesive layer and the release layer are compounded in sequence; wherein the functional layer is provided with a plurality of holes extending along the thickness direction and penetrating through the functional layer.

[0009] Further, the functional layer is formed by film forming of non-woven fabric and / or fiber fabric.

[0010] Further, the functional layer is any one of polyester fiber, polyamide fiber, polyacrylonitrile fiber, polyvinyl alcohol fiber, polyvinyl chloride fiber, glass fiber, bamboo fiber, protein fiber and asbestos.

[0011] Further, the pore size of the hole is 0.1-50μm, and the porosity of the functional layer is 10%-50%.

[0012] Further, the functional layer is a colored layer, and the color of the colored layer is any one of blue, green, brown, tan and black.

[0013] Further, the thickness ratio of the first PET layer, the first adhesive layer and the functional layer is 5-10:1-2:5-25.

[0014] In a preferred embodiment, a scheme about the specific design of the substrate layer and the adhesive layer is provided.

[0015] The substrate layer further comprises a second PET layer and a second adhesive layer, and the second PET layer, the second adhesive layer, the first PET layer, the first adhesive layer, the functional layer, the adhesive layer and the release layer are sequentially compounded.

[0016] Further, the thickness of the first PET layer or the second PET layer is 15-25μm, and the thickness of the first adhesive layer or the second adhesive layer is 5-20μm.

[0017] Further, the thickness ratio of the substrate layer and the adhesive layer is 5-15:1.

[0018] Based on the same design idea, the utility model further provides a power battery, the power battery includes the novel power battery wrapping film.

[0019] In summary, compared with the prior art, the novel power battery wrapping film and the power battery thereof provided by the utility model have at least the following technical effects:

[0020] 1) The functional layer adopts a porous structure, compared with a solid film layer, the design mode of the porous structure can reduce the shear modulus and bulk modulus of the film material, thereby improving the flexibility of the wrapping film, and a common problem of the wrapping film at present is that the corners thereof are prone to natural warping after wrapping, and improving the flexibility of the wrapping film helps to solve the problem.

[0021] 2) By setting the porous structure in the functional layer, the bending degree can be improved at the micro level, and when the power battery is wrapped by the wrapping film or is stretched, the wrapping film is provided with a certain deformation space, and the flexibility of the wrapping film is further increased;

[0022] 3) By setting the porous structure in the functional layer, the contact surface part of the glue layer and the functional layer is embedded in the hole to form an embedded structure, so that the mechanical interlocking effect is formed between the functional layer and the glue layer, the bonding performance between the two is improved, and then the film stability between the films is improved, so that the wrapping film is not prone to interlayer displacement and peeling problems;

[0023] 4) The functional layer is formed by using any one of glass fiber, non-woven fabric, bamboo fiber and glass powder, the material itself has high voltage resistance performance, and due to the good film stability between the films and the stable connection between the film layers, the high voltage is not easy to break down. In addition, the porous structure can also provide a deformation space for the wrapping film, and the wrapping film is not easy to be excessively deformed, warped or cracked under high voltage. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is a schematic view of the interlayer structure of the novel power battery wrapping film of the utility model;

[0025] Figure 2 It is a top view of the functional layer of the utility model;

[0026] In the drawings, the meanings of the reference signs are as follows:

[0027] 1, first PET layer; 2, first glue layer; 3, functional layer; 31, hole; 4, adhesive layer; 5, release layer; 6, second PET layer; 7, second glue layer. DETAILED DESCRIPTION

[0028] In order to better understand and implement, the technical solutions in the embodiments of the utility model will be clearly and completely described below in combination with the drawings in the embodiments of the utility model.

[0029] In the description of the utility model, it should be explained that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the utility model.

[0030] 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 belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application.

[0031] Embodiment 1

[0032] In the first embodiment of the application, a technical scheme about the interlayer structure setting and the specific design of the functional layer of the novel power battery wrapping film is provided.

[0033] Referring to Figure 1 and Figure 2 According to the embodiment of the application, the novel power battery wrapping film includes a substrate layer, an adhesive layer 4 and a release layer 5. The substrate layer includes a first PET layer 1, a first adhesive layer 2 and a functional layer 3. The first PET layer 1, the first adhesive layer 2, the functional layer 3, the adhesive layer 4 and the release layer 5 are sequentially compounded. The substrate layer has a certain thickness and is used as the substrate structure of the entire wrapping film adhesive tape. The substrate layer is made of insulating material and is used for insulation protection after wrapping the power battery. Further, the release layer 5 is provided in the embodiment to protect the adhesive layer 4 and prevent the adhesive layer 4 from delamination and adhesive drop during unwinding of the wrapping film adhesive tape. The adhesive layer 4 is provided to realize the close adhesion between the wrapping film and the battery. After removing the release layer 5, the adhesive layer 4 is used to adhere to the outside of the battery, thereby realizing the wrapping of the wrapping film on the battery.

[0034] In the technical scheme of the embodiment, the functional layer 3 is provided with a plurality of holes 31 extending along the thickness direction and penetrating through the functional layer 3, so as to form a porous structure in the width extension direction and the length extension direction of the functional layer 3. The holes 31 of the functional layer 3 can be regularly arranged or irregularly arranged. The holes 31 can be circular holes, square holes or other shaped hole structures. Preferably, the holes 31 are circular holes based on the convenience of the process.

[0035] Compared with the solid film layer, the functional layer 3 can reduce the shear modulus and bulk modulus of the film material by adopting the design of the porous structure, thereby improving the flexibility of the wrapping film. At present, a common problem of the wrapping film is that the corners of the wrapping film are prone to natural warping after wrapping. Improving the flexibility of the wrapping film can help solve this problem. In addition, the design of the porous structure can improve the bending degree of the film material at the micro level, providing a certain deformation space for the wrapping film when the wrapping film is bent to wrap the power battery or stretched, thereby further increasing the flexibility of the wrapping film. In addition, the porous structure can embed the contact surface part of the first adhesive layer 2 and the functional layer 3 into the hole 31 to form a fitting structure, thereby forming a mechanical interlocking effect between the functional layer 3 and the first adhesive layer 2, improving the bonding performance between the two, and further improving the interlayer stability of the wrapping film to ensure that the wrapping film is not prone to interlayer displacement and peeling.

[0036] In a preferred scheme of this embodiment, the thickness ratio of the first PET layer 1, the first adhesive layer 2 and the functional layer 3 in the substrate layer can be set to 5-10: 1-2: 5-25, and the thickness ratio of the three is preferably set to 5: 1: 10.

[0037] In an optional scheme of this embodiment, the functional layer 3 is formed by non-woven fabric and / or fiber fabric, and is specifically formed by any one or at least one of polyester fiber, polyamide fiber, polyacrylonitrile fiber, polyvinyl alcohol fiber, polyvinyl chloride fiber, glass fiber, bamboo fiber, protein fiber and asbestos. The above-mentioned materials have high voltage resistance and high temperature resistance, and high voltage is not easy to break down. Combined with the high interlayer stability between the layers of the film, the voltage resistance of the wrapping film is further improved. In addition, the porous structure provided in the functional layer 3 can also provide a deformation space for the wrapping film, and the wrapping film is not easy to deform excessively, warp or crack under high voltage.

[0038] In an optional scheme of this embodiment, according to the actual needs of different use scenarios combined with the material properties of the film material, the thickness of the functional layer 3 can be set to 5-50 μm, and when the functional layer 3 adopts glass fiber material, the thickness is preferably set to 5 μm; when the functional layer 3 adopts non-woven fabric material, the thickness is preferably set to 10 μm; when the functional layer 3 adopts bamboo fiber material, the thickness is preferably set to 30 μm; and when the functional layer 3 adopts glass powder material, the thickness is preferably set to 40 μm.

[0039] The pore diameter of the hole 31 can be set to 0.1-50 μm, and preferably to 0.1 μm, 10 μm, 20 μm, 30 μm, 40 μm or 50 μm according to the length and width of the wrapping film adhesive tape actually used. The porosity of the functional layer 3 can be set to 10%-50%, and preferably to 10%, 20%, 30%, 40% or 50%.

[0040] In an optional scheme of this embodiment, the functional layer 3 is a colored layer, that is, the functional layer 3 is provided with a color different from other film layers, for color identification, facilitating identification and thus completing the film pasting. Specifically, the color of the colored layer can be set to any one of blue, green, brown, tan and black, and preferably to blue. The light transmittance of the wrapping film is preferably set to less than or equal to 90%.

[0041] In an optional scheme of this embodiment, the functional layer 3 is a two-dimensional code layer, that is, the functional layer 3 is provided with a two-dimensional code, for identification and traceability, so that the information such as the material, process and production process of the battery can be traced through subsequent identification equipment without coding on the battery shell. Specifically, the two-dimensional code layer is provided with a printing surface away from the surface of the adhesive layer 4, and the two-dimensional code is arranged on the printing surface of the two-dimensional code layer.

[0042] Embodiment 2

[0043] In the second embodiment of the utility model, a specific design of the base material layer and the adhesive layer is provided on the basis of the first embodiment.

[0044] In the technical scheme of this embodiment, the base material layer further comprises a second PET layer 6 and a second adhesive layer 7, and the second PET layer 6, the second adhesive layer 7, the first PET layer 1, the first adhesive layer 2, the functional layer 3, the adhesive layer 4 and the release layer 5 are sequentially compounded. By arranging the double-layer PET layer and the adhesive layer, the thickness of the single-layer PET layer and the adhesive amount of the adhesive layer can be reduced, the protection performance of the wrapping film is enhanced while the film layer thickness is maintained, and whether to use the second PET layer 6 and the second adhesive layer 7 can be selected according to actual needs.

[0045] In a preferred scheme of this embodiment, the thickness of the first PET layer 1 or the second PET layer 6 can be set to 15-25 μm, and preferably to 15 μm, 20 μm or 25 μm. The thickness of the first adhesive layer 2 or the second adhesive layer 7 can be set to 5-20 μm, and preferably to 5 μm, 10 μm, 15 μm or 20 μm. Further, in order to facilitate the preparation process of the wrapping film, the thickness of the first PET layer 1 and the second PET layer 6 is preferably set to be equal, and the thickness of the first adhesive layer 2 and the second adhesive layer 7 is preferably set to be equal.

[0046] In another preferred aspect of the embodiment, the thickness ratio of the substrate layer and the adhesive layer 4 can be set to 5-15:1, and the thickness ratio of both is preferably set to 10:1.

[0047] Embodiment 3

[0048] Based on the same design idea, the utility model further provides an embodiment about a power battery, which comprises the novel power battery wrapping film of the first and second embodiments. In use, the wrapping film is wrapped on the outer surface of the power battery.

[0049] In summary, the novel power battery wrapping film and the power battery thereof provided by the utility model can significantly improve the flexibility of the wrapping film by setting the functional layer made of any one of glass fiber, non-woven fabric, bamboo fiber and glass powder, solve the natural warping phenomenon of the edges and corners after wrapping, enhance the film stability between the layers of the wrapping film, ensure that the wrapping film is not prone to interlayer displacement and peeling, and is not easily broken down under high voltage, so that the wrapping film is not prone to excessive deformation, warping or cracking, and the like.

[0050] The technical means disclosed by the utility model scheme is not limited to the technical means disclosed by the above-mentioned embodiments, and also includes the technical scheme composed of any combination of the above technical features. It should be noted that, for ordinary skilled persons in the art, without departing from the principles of the utility model, a number of improvements and refinements can be made, and these improvements and refinements are also considered to be within the protection scope of the utility model.

Claims

1. A novel power battery wrapping film, characterized in that, Comprising: The base material layer, the adhesive layer and the release layer, the base material layer comprises a first PET layer, a first glue layer and a functional layer, the first PET layer, the first glue layer, the functional layer, the adhesive layer and the release layer are compounded in sequence; wherein, the functional layer is provided with a plurality of holes extending along the thickness direction and penetrating through the functional layer.

2. The novel power battery wrapping film according to claim 1, characterized in that, The functional layer is formed by non-woven fabric and / or fiber cloth film.

3. The novel power battery wrapping film according to claim 2, characterized in that, The functional layer is any one of polyester fiber, polyamide fiber, polyacrylonitrile fiber, polyvinyl alcohol fiber, polyvinyl chloride fiber, glass fiber, bamboo fiber, protein fiber and asbestos.

4. The novel power battery wrapping film according to claim 1, characterized in that, The pore size of the hole is 0.1-50μm, and the porosity of the functional layer is 10%-50%.

5. The novel power battery wrapping film according to claim 1, wherein, The functional layer is a colored layer, and the color of the colored layer is any one of blue, green, brown, brown and black.

6. The novel power battery wrapping film according to any one of claims 1-5, characterized in that, The thickness ratio of the first PET layer, the first glue layer and the functional layer is 5-10:1-2:5-25.

7. The novel power battery wrapping film according to claim 1, wherein, The base material layer further comprises a second PET layer and a second glue layer, and the second PET layer, the second glue layer, the first PET layer, the first glue layer, the functional layer, the adhesive layer and the release layer are compounded in sequence.

8. The novel power battery wrapping film according to claim 7, characterized in that, The thickness of the first PET layer or the second PET layer is 15-25μm, and the thickness of the first glue layer or the second glue layer is 5-20μm.

9. The novel power battery wrapping film according to claim 8, characterized in that, The thickness ratio of the base material layer and the adhesive layer is 5-15:

1.

10. A power cell, characterized by The power battery comprises the novel power battery wrapping film according to any one of claims 1-9.

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