Power battery with protective film structure

Abstract

The embodiment of the utility model provides a power battery with a protective film structure, which comprises a battery cell, a shell and a protective film, the protective film is arranged between the battery cell and the shell, the protective film comprises a heat-resistant layer, an insulating layer and a flame-retardant layer, the insulating layer is arranged between the heat-resistant layer and the flame-retardant layer, a second adhesive layer is arranged between the heat-resistant layer and the insulating layer, and the second adhesive layer is arranged between the heat-resistant layer and the flame-retardant layer. A third adhesive layer is arranged between the insulating layer and the flame-retardant layer, a release layer is further arranged above the heat-resistant layer, and a first adhesive layer is arranged between the release layer and the heat-resistant layer. The composite protective film has the beneficial effects that a composite protective film structure of the heat-resistant layer, the insulating layer and the flame-retardant layer is coated on the outer layer of the battery cell, so that relatively safe protection is provided for the power battery; the heat-resistant, insulating and flame-retardant properties are realized, so that the power battery can adapt to the conditions of large temperature difference, high-heat environment and the like, and the adhesion degree between the protective film and the battery cell is improved by clinging the first adhesive layer to the battery cell.

Description

Technical Field

[0001] This utility model relates to the field of power battery protection, and in particular to a power battery with a protective film structure. Background Technology

[0002] With the development of new energy technologies, mobile devices powered by power batteries are gaining an increasingly larger market share, and the safety performance of power batteries, as the core of energy, is of paramount importance.

[0003] Currently, in the manufacturing process of power batteries, tape is usually used to wrap the outside of the battery cells to prevent the battery body from being contaminated by electrolyte leakage or mechanical scratches due to uncontrollable factors during material transfer or assembly. This protects the battery cells and, to a certain extent, separates the battery cells with electrodes connected in series, thus temporarily slowing down the deterioration caused by individual cell failures.

[0004] Existing power battery protective tapes typically consist of a PET film with flame-retardant properties coated with an acrylic adhesive layer. While they possess certain flame-retardant properties, their heat resistance, insulation, and adhesion have become insufficient to meet the requirements due to the increasing complexity of power battery usage environments (such as large temperature differences and high-heat environments). Utility Model Content

[0005] (a) Technical problems to be solved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a power battery with a protective film structure, which solves the technical problem that the heat resistance, insulation and adhesion of the power battery can no longer meet the requirements of use due to the increasing complexity of the environment in which the power battery is used.

[0007] (II) Technical Solution

[0008] The purpose of this utility model is to provide a power battery with a protective film structure, which includes a cell, a shell, and a protective film. The protective film is disposed between the cell and the shell. The thickness of the protective film is 0.15 to 0.25 mm. The protective film includes a heat-resistant layer, an insulating layer, and a flame-retardant layer. The insulating layer is disposed between the heat-resistant layer and the flame-retardant layer. A second adhesive layer is disposed between the heat-resistant layer and the insulating layer. A third adhesive layer is disposed between the insulating layer and the flame-retardant layer. A release layer is also disposed above the heat-resistant layer. A first adhesive layer is disposed between the release layer and the heat-resistant layer. The first adhesive layer is tightly attached to the surface of the cell.

[0009] Preferably, the release layer is made of one of polypropylene, polyethylene terephthalate, or polyethylene.

[0010] Preferably, the heat-resistant layer is made of a double-sided corona-electrode PET film with a thickness of 0.02 to 0.025 mm.

[0011] Preferably, the insulating layer is made of one of polypropylene, polyethylene terephthalate, polyethylene, or biaxially oriented polypropylene.

[0012] Preferably, the flame-retardant layer is made of acetate cloth.

[0013] Preferably, the second adhesive layer is an epoxy resin adhesive.

[0014] Preferably, the third adhesive layer is a flame-retardant acrylic adhesive.

[0015] Preferably, the first adhesive layer is a high-viscosity modified acrylic adhesive.

[0016] (III) Beneficial Effects

[0017] By coating the outer layer of the battery cell with a composite protective film structure consisting of a heat-resistant layer, an insulating layer, and a flame-retardant layer, a relatively safe protection is provided for the power battery. This achieves heat resistance, insulation, and flame retardancy, ensuring that the power battery can adapt to conditions such as large temperature differences and high-temperature environments. Furthermore, the first adhesive layer adheres tightly to the battery cell, improving the adhesion between the protective film and the battery cell. To a certain extent, this structure controls the hazards caused by battery cell failures within the battery casing or temporarily prevents the further aggravation of electrolyte leakage and combustion hazards. Attached Figure Description

[0018] The accompanying drawings are provided to further understand the technical solution of this utility model and constitute a part of the specification. They are used together with the embodiments of this utility model to explain the technical solution of this utility model, and do not constitute a limitation on the technical solution of this utility model.

[0019] Figure 1 This is a diagram of the protective film structure of a power battery with a protective film structure;

[0020] Figure 2 This is a schematic diagram showing the usage status of the protective film of a power battery with a protective film structure.

[0021] Explanation of reference numerals in the attached figures:

[0022] 1. Battery cell; 2. Outer casing; 3. Protective film; 31. Heat-resistant layer; 32. Insulating layer; 33. Flame-retardant layer; 34. First adhesive layer; 35. Second adhesive layer; 36. Third adhesive layer; 4. Release layer. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0024] The following is in conjunction with the appendix Figures 1 to 2 To further describe, this utility model discloses a protective film 3 structure for a power battery, including a cell 1, a shell 2 and a protective film 3. During the power battery PACK process, the protective film 3 is placed between the cell 1 and the shell 2. Without affecting the series and parallel connection of the circuit, the assembled cell 1 is wrapped and placed inside the shell 2 of the power battery through the protective film 3.

[0025] The total thickness of the protective film 3 is 0.15 to 0.25 mm. The protective film 3 includes a heat-resistant layer 31, an insulating layer 32, and a flame-retardant layer 33. It can be seen that the protective film 3 is formed by bonding the aforementioned film layers with heat resistance, insulation and flame retardant properties with an adhesive.

[0026] The protective film 3 is specifically structured in layers by placing an insulating layer 32 between the heat-resistant layer 31 and the flame-retardant layer 33. The heat-resistant layer 31 and the flame-retardant layer 33 are laminated to both sides of the insulating layer 32. A second adhesive layer 35 is placed between the heat-resistant layer 31 and the insulating layer 32, which is achieved by applying an epoxy resin adhesive between the two layers. A third adhesive layer 36 is placed between the insulating layer 32 and the flame-retardant layer 33, which is achieved by applying a flame-retardant acrylic adhesive between the two layers. In addition, a release layer 4 is placed above the heat-resistant layer 31, and a first adhesive layer 34 is placed between the release layer 4 and the heat-resistant layer 31. This first adhesive layer 34 is a high-viscosity modified acrylic adhesive. After the release layer 4 is peeled off, the first adhesive layer 34 adheres tightly to the surface of the battery cell 1, further improving the adhesion between the protective film 3 and the battery cell 1.

[0027] In a preferred embodiment, the release layer 4 is made of one of polypropylene, polyethylene terephthalate, or polyethylene.

[0028] In a preferred embodiment, the heat-resistant layer 31 is made of a double-sided corona-electrode PET film with a thickness of 0.02 to 0.025 mm.

[0029] In a preferred embodiment, the insulating layer 32 is made of one of polypropylene, polyethylene terephthalate, polyethylene, or biaxially oriented polypropylene.

[0030] In a preferred embodiment, the flame-retardant layer 33 is made of acetate cloth.

[0031] In a preferred embodiment, the second adhesive layer 35 is an epoxy resin adhesive.

[0032] In a preferred embodiment, the third adhesive layer 36 is a flame-retardant acrylic adhesive.

[0033] In a preferred embodiment, the first adhesive layer 34 is a high-viscosity modified acrylic adhesive.

[0034] In summary, by coating the outer layer of the battery cell with a composite protective film structure consisting of a heat-resistant layer, an insulating layer, and a flame-retardant layer, a relatively safe protection is provided for the power battery. This achieves heat resistance, insulation, and flame retardancy, ensuring that the power battery can adapt to conditions such as large temperature differences, high-temperature environments, and humid heat. Furthermore, the first adhesive layer adheres tightly to the battery cell, improving the adhesion between the protective film and the battery cell. To a certain extent, this structure controls the hazards caused by battery cell failure within the battery casing or temporarily prevents the further aggravation of electrolyte leakage and combustion hazards.

[0035] Although embodiments of the present invention have been shown above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications and variations to the above embodiments, but such modifications are all included within the broad scope of the foregoing disclosure, drawings and claims.

Claims

1. A power battery with a protective film structure, comprising an electric core, a shell and a protective film, the protective film is arranged between the electric core and the shell, characterized in that: The protective film has a thickness of 0.15 to 0.25 mm and includes a heat-resistant layer, an insulating layer, and a flame-retardant layer. The insulating layer is disposed between the heat-resistant layer and the flame-retardant layer. A second adhesive layer is disposed between the heat-resistant layer and the insulating layer. A third adhesive layer is disposed between the insulating layer and the flame-retardant layer. A release layer is also disposed above the heat-resistant layer. A first adhesive layer is disposed between the release layer and the heat-resistant layer. The first adhesive layer is tightly attached to the surface of the battery cell. The release layer is made of one of polypropylene, polyethylene terephthalate, and polyethylene. The heat-resistant layer is made of a double-sided corona-electroplated PET film with a thickness of 0.02 to 0.025 mm. The insulating layer is made of one of the following materials: polypropylene, polyethylene terephthalate, polyethylene, and biaxially oriented polypropylene. The flame-retardant layer is made of acetate cloth; The second adhesive layer is an epoxy resin adhesive; The third adhesive layer is a flame-retardant acrylic adhesive; The first adhesive layer is a high-viscosity modified acrylic adhesive.

Images