High-performance aluminum plastic film

Abstract

The utility model discloses a high-performance aluminum plastic film which sequentially comprises a heat-sealing layer, an aluminum foil layer and a protective layer from inside to outside, a heat-resisting layer is arranged between the heat-sealing layer and the aluminum foil layer, an insulating layer is arranged between the aluminum foil layer and the protective layer, the heat-sealing layer is a casting polypropylene layer, the heat-resisting layer is a polyimide layer, and the insulating layer is a polyimide layer. The isolation layer is a polyvinylidene chloride layer, and the protection layer is a biaxially oriented polyester layer. The polyimide layer is additionally arranged between the casting polypropylene layer and the aluminum foil layer, so that the high-temperature-resistant requirement of the aluminum-plastic film is met by utilizing the high-temperature-resistant performance of polyimide, and the polyvinylidene chloride layer is additionally arranged between the aluminum foil layer and the protective layer, so that the isolation performance of the aluminum-plastic film is improved, and the service life of the aluminum-plastic film is prolonged. The outer protective layer is changed from nylon to biaxially oriented polyester, so that the chemical stability of the aluminum-plastic film is enhanced.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium battery packaging, in particular to a high-performance aluminum-plastic film. Background Art

[0002] Aluminum-plastic film typically consists of an outer protective layer (nylon film, polyester film), an intermediate aluminum foil layer, and an inner heat-seal layer (polypropylene film). With the development of electronic devices and new energy vehicles, the demand for high-performance batteries is growing. Aluminum-plastic film soft packs, as the battery packaging method with the highest energy density, perfectly align with the trend of high-energy density batteries. As solid-state batteries mature, the requirements for aluminum-plastic film in terms of high-temperature resistance and barrier properties will inevitably increase. However, existing aluminum-plastic films still have room for improvement in terms of heat resistance and barrier properties. Utility Model Content

[0003] The utility model aims to solve the defects in the prior art and provides a high-performance aluminum-plastic film, which can improve the high-temperature resistance and insulation performance of the aluminum-plastic film.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0005] A high-performance aluminum-plastic film comprises, from the inside out, a heat-sealing layer, an aluminum foil layer, and a protective layer. A heat-resistant layer is provided between the heat-sealing layer and the aluminum foil layer, and an insulating layer is provided between the aluminum foil layer and the protective layer. The heat-sealing layer is a cast polypropylene layer, the heat-resistant layer is a polyimide layer, the insulating layer is a polyvinylidene chloride layer, and the protective layer is a biaxially oriented polyester layer. By adding a polyimide layer between the cast polypropylene layer and the aluminum foil layer, the high-temperature resistance of the polyimide is utilized to meet the high-temperature resistance requirements of the aluminum-plastic film. By adding a polyvinylidene chloride layer between the aluminum foil layer and the protective layer, the insulating properties of the aluminum-plastic film are improved. By replacing the outer protective layer with biaxially oriented polyester instead of nylon, the chemical stability of the aluminum-plastic film is enhanced.

[0006] As a preferred technical solution, the polyimide layer is a polyimide film that has been sintered.

[0007] As a preferred technical solution, the thickness of the heat-resistant layer is 15 to 25 μm.

[0008] As a preferred technical solution, the cast polypropylene layer is a three-layer co-extruded homopolypropylene film or a three-layer co-extruded copolymer polypropylene film.

[0009] As a preferred technical solution, the thickness of the heat-sealing layer is 35 to 45 μm.

[0010] As a preferred technical solution, a chromium ion passivation treatment layer is formed on the surface of the aluminum foil layer.

[0011] As a preferred technical solution, the thickness of the aluminum foil layer is 35 to 45 μm.

[0012] As a preferred technical solution, the polyvinylidene chloride layer and the biaxially oriented polyester layer are co-extruded to form a composite film.

[0013] As a preferred technical solution, the thickness of the insulating layer is 15 to 25 μm.

[0014] As a preferred technical solution, the thickness of the protective layer is 10 to 20 μm.

[0015] Compared with the prior art, the utility model has obvious advantages and beneficial effects. Specifically, by adding a polyimide layer between the cast polypropylene layer and the aluminum foil layer, the high temperature resistance of the polyimide is utilized to meet the high temperature resistance requirement of the aluminum-plastic film. By adding a polyvinylidene chloride layer between the aluminum foil layer and the protective layer, the insulation performance of the aluminum-plastic film is improved. By replacing the outer protective layer with nylon and biaxially oriented polyester, the chemical stability of the aluminum-plastic film is enhanced.

[0016] In order to more clearly illustrate the structural features, technical means and specific purposes and functions achieved by the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments: BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic cross-sectional view of an embodiment of the present invention.

[0018] Description of the accompanying drawings:

[0019] 1. Heat seal layer 2. Heat resistant layer 3. Aluminum foil layer

[0020] 4. Insulation layer 5. Protective layer. DETAILED DESCRIPTION

[0021] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the position or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0022] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model based on the specific circumstances.

[0023] like Figure 1 As shown, a high-performance aluminum-plastic film comprises, from inside to outside, a heat-sealing layer 1, an aluminum foil layer 3, and a protective layer 5. A heat-resistant layer 2 is disposed between the heat-sealing layer 1 and the aluminum foil layer 3, and an insulating layer 4 is disposed between the aluminum foil layer 3 and the protective layer 5. The heat-sealing layer 1 is a cast polypropylene layer, the heat-resistant layer 2 is a polyimide layer, the insulating layer 4 is a polyvinylidene chloride layer, and the protective layer 5 is a biaxially oriented polyester layer. In this utility model, the heat-sealing layer 1 has a thickness of 35 to 45 μm, the heat-resistant layer 2 has a thickness of 15 to 25 μm, the aluminum foil layer 3 has a thickness of 35 to 45 μm, the insulating layer 4 has a thickness of 15 to 25 μm, and the protective layer 5 has a thickness of 10 to 20 μm.

[0024] In the present invention, the polyimide layer is a sintered polyimide film. Specifically, the polyimide film is formed by evenly coating a polyamic acid resin solution on the surface of an aluminum foil. After the solvent evaporates, the aluminum foil with the polyamic acid film is sintered. The sintering process improves the peeling force between the polyimide film and the aluminum foil, thereby providing better protection for the aluminum foil layer 3. A chromium ion passivation treatment layer is formed on the surface of the aluminum foil layer 3. By passivating the aluminum foil with a chromium ion passivation solution, the bonding force between the heat-resistant layer 2 and the insulating layer 4 and the aluminum foil layer 3 is increased.

[0025] In the present invention, the cast polypropylene layer is a three-layer co-extruded homopolypropylene film or a three-layer co-extruded copolymer polypropylene film, and the polyvinylidene chloride layer and the biaxially oriented polyester layer are co-extruded to form a composite film.

[0026] In summary, the present invention increases the high temperature resistance of the aluminum-plastic film from 120°C to 140°C by adding a polyimide layer between the cast polypropylene layer and the aluminum foil layer 3, thereby utilizing the high temperature resistance of the polyimide to meet the high temperature resistance requirements of the aluminum-plastic film. The insulation performance of the aluminum-plastic film is improved by adding a polyvinylidene chloride layer between the aluminum foil layer 3 and the protective layer 5. The chemical stability of the aluminum-plastic film is enhanced by replacing the outer protective layer 5 with nylon and biaxially oriented polyester.

[0027] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Therefore, any modifications, equivalent replacements, improvements, etc. made to the above embodiments based on the technical practice of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A high-performance aluminum-plastic film, comprising a heat-sealing layer, an aluminum foil layer and a protective layer from the inside out, characterized in that: A heat-resistant layer is provided between the heat-sealing layer and the aluminum foil layer, and an insulating layer is provided between the aluminum foil layer and the protective layer. The heat-sealing layer is a cast polypropylene layer, the heat-resistant layer is a polyimide layer, the insulating layer is a polyvinylidene chloride layer, and the protective layer is a biaxially oriented polyester layer.

2. A high performance aluminum-plastic film according to claim 1, characterized in that: The polyimide layer is a polyimide film that has been sintered.

3. A high-performance aluminum-plastic film according to claim 1 or 2, characterized in that: The thickness of the heat-resistant layer is 15 to 25 μm.

4. The high-performance aluminum-plastic film according to claim 1, characterized in that: The cast polypropylene layer is a three-layer co-extruded homopolypropylene film or a three-layer co-extruded copolymer polypropylene film.

5. A high-performance aluminum-plastic film according to claim 1 or 4, characterized in that: The thickness of the heat sealing layer is 35 to 45 μm.

6. The high-performance aluminum-plastic film according to claim 1, characterized in that: A chromium ion passivation treatment layer is formed on the surface of the aluminum foil layer.

7. A high-performance aluminum-plastic film according to claim 1 or 6, characterized in that: The thickness of the aluminum foil layer is 35 to 45 μm.

8. The high-performance aluminum-plastic film according to claim 1, characterized in that: The polyvinylidene chloride layer and the biaxially oriented polyester layer are co-extruded to form a composite film.

9. A high-performance aluminum-plastic film according to claim 1 or 8, characterized in that: The thickness of the insulating layer is 15 to 25 μm.

10. A high-performance aluminum-plastic film according to claim 1 or 8, characterized in that: The thickness of the protective layer is 10 to 20 μm.

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