Corrosion-resistant aluminum plastic film for lithium battery

Abstract

The utility model relates to the technical field of battery packaging materials, in particular to a corrosion-resistant aluminum plastic film for a lithium battery, which comprises a high-barrier base layer and a corrosion-resistant aluminum alloy outer layer, a corrosion-resistant coating is arranged at the lower end of the high-barrier base layer, and a connecting adhesive layer for adhering the inner side and the outer side is arranged between the high-barrier base layer and the corrosion-resistant aluminum alloy outer layer. According to the corrosion-resistant aluminum plastic film for the lithium battery disclosed by the utility model, the durability and reliability of the corrosion-resistant aluminum plastic film in actual use are greatly enhanced by utilizing the corrosion-resistant aluminum alloy outer layer, and the corrosion-resistant coating is arranged, so that the corrosion of electrolyte can be effectively resisted by utilizing the polytetrafluoroethylene coating; the aluminum oxide coating not only provides excellent barrier performance, but also improves the electrochemical stability of the corrosion-resistant aluminum-plastic film, the aluminum oxide coating and the corrosion-resistant aluminum-plastic film are used in cooperation and supplement each other, the electrolyte corrosion resistance is greatly enhanced, and meanwhile, the durability and reliability of the corrosion-resistant aluminum-plastic film in actual use are greatly enhanced through the arrangement of the high-barrier base layer.

Description

Technical Field

[0001] The utility model relates to the technical field of battery packaging materials, in particular to a corrosion-resistant aluminum-plastic film for lithium batteries. Background Technique

[0002] As a material with properties such as oxygen barrier, moisture resistance, puncture resistance, ultraviolet resistance, and chemical resistance, the aluminum-plastic film is widely used in the packaging of soft-pack lithium batteries.

[0003] Although the aluminum-plastic film commonly used in the current lithium battery packaging has good barrier properties and mechanical strength, it is prone to chemical corrosion in specific corrosive environments (such as high temperature and high humidity or when encountering electrolyte penetration), which affects the sealing performance and safety of the battery. Therefore, we propose a corrosion-resistant aluminum-plastic film for lithium batteries. Content of the Utility Model

[0004] The main purpose of the utility model is to provide a corrosion-resistant aluminum-plastic film for lithium batteries, which can effectively solve the problems in the background technique.

[0005] To achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0006] A corrosion-resistant aluminum-plastic film for lithium batteries, including a high-barrier base layer and a corrosion-resistant aluminum alloy outer layer. A corrosion-resistant coating is provided at the lower end of the high-barrier base layer, and an adhesive layer for bonding the inner and outer sides is provided between the high-barrier base layer and the corrosion-resistant aluminum alloy outer layer.

[0007] Preferably, the high-barrier base layer includes a polyethylene film, PVDC coating layers are provided at both the upper and lower ends of the polyethylene film, and aluminum foil layers are provided at the ends of the two PVDC coating layers away from the polyethylene film.

[0008] Preferably, the upper end of the aluminum foil layer located at the upper part is fixedly connected to the corrosion-resistant aluminum alloy outer layer through an adhesive layer.

[0009] Preferably, the corrosion-resistant coating includes an alumina coating and a polytetrafluoroethylene coating. The polytetrafluoroethylene coating is provided at the lower end of the alumina coating, and the alumina coating is provided at the lower end of the lower aluminum foil layer.

[0010] Preferably, the thickness of the corrosion-resistant aluminum alloy outer layer is 15um.

[0011] Preferably, the adhesive layer is an epoxy resin layer.

[0012] Compared with the prior art, the utility model has the following beneficial effects:

[0013] 1. The utility model retains the high barrier property of the PVDC coating layer by setting a high barrier base layer and arranging PVDC coating layers at both the upper and lower ends of the polyethylene film. Meanwhile, it utilizes the good processing performance of the polyethylene film, making it suitable for large-scale production. Additionally, the aluminum foil layer can significantly improve the barrier performance, blocking light, oxygen, and moisture while maintaining good mechanical properties and cost-effectiveness.

[0014] 2. The utility model sets a corrosion-resistant coating. The polytetrafluoroethylene coating has excellent chemical inertness and corrosion resistance, effectively resisting the erosion of the electrolyte. The alumina coating not only provides excellent barrier performance but also improves the electrochemical stability of the corrosion-resistant aluminum-plastic film, significantly contributing to enhancing the battery performance. The two coatings are used in combination, complementing each other, greatly enhancing the ability to resist electrolyte corrosion and extending the service life and safety of the corrosion-resistant aluminum-plastic film.

[0015] 3. The utility model utilizes the strong self-passivation ability of the corrosion-resistant aluminum alloy outer layer. That is, when slightly scratched or worn, the exposed aluminum alloy matrix can quickly react with the oxygen in the air to reform the oxide film, thus greatly enhancing the durability and reliability of the corrosion-resistant aluminum-plastic film in actual use. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of a corrosion-resistant aluminum-plastic film for lithium batteries according to the utility model;

[0017] Figure 2 It is a schematic diagram of the composition structure of a corrosion-resistant aluminum-plastic film for lithium batteries according to the utility model;

[0018] Figure 3 It is a schematic diagram of the composition structure of the high barrier base layer of a corrosion-resistant aluminum-plastic film for lithium batteries according to the utility model;

[0019] Figure 4 It is a schematic diagram of the composition structure of the corrosion-resistant coating of a corrosion-resistant aluminum-plastic film for lithium batteries according to the utility model.

[0020] In the figure: 1. High barrier base layer; 2. Corrosion-resistant aluminum alloy outer layer; 3. Corrosion-resistant coating; 4. Connecting adhesive layer; 5. Polyethylene film; 6. PVDC coating layer; 7. Aluminum foil layer; 31. Alumina coating; 32. Polytetrafluoroethylene coating. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] To make the technical means, creative features, achieved purposes, and functions of the utility model easy to understand, the following further elaborates the utility model in conjunction with specific embodiments.

[0022] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0023] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0024] Please refer to Figures 1-4 , the present utility model provides a technical solution:

[0025] A corrosion-resistant aluminum-plastic film for lithium batteries, comprising a high-barrier base layer 1 and a corrosion-resistant aluminum alloy outer layer 2. A corrosion-resistant coating 3 is provided at the lower end of the high-barrier base layer 1, and a connection adhesive layer 4 for bonding the inner and outer sides is provided between the high-barrier base layer 1 and the corrosion-resistant aluminum alloy outer layer 2.

[0026] In this embodiment, the high-barrier base layer 1 includes a polyethylene film 5. PVDC coating layers 6 are provided at both the upper and lower ends of the polyethylene film 5, and aluminum foil layers 7 are provided at one ends of the two PVDC coating layers 6 away from the polyethylene film 5. The upper end of the aluminum foil layer 7 located in the upper part is fixedly connected to the corrosion-resistant aluminum alloy outer layer 2 through the connection adhesive layer 4. By providing the PVDC coating layers 6 at both the upper and lower ends of the polyethylene film 5, not only the high-barrier characteristics of the PVDC coating layers 6 are retained, but also the good processing performance of the polyethylene film 5 is utilized, which is suitable for large-scale production. At the same time, the aluminum foil layer 7 can significantly improve the barrier performance, block light, oxygen and moisture, and at the same time maintain good mechanical properties and cost-effectiveness.

[0027] In this embodiment, the corrosion-resistant coating 3 includes an alumina coating 31 and a polytetrafluoroethylene coating 32. The polytetrafluoroethylene coating 32 is provided at the lower end of the alumina coating 31, and the alumina coating 31 is provided at the lower end of the lower aluminum foil layer 7. The polytetrafluoroethylene coating 32 has excellent chemical inertness and corrosion resistance, and can effectively resist the erosion of the electrolyte. The alumina coating 31 not only provides excellent barrier properties, but also improves the electrochemical stability of the corrosion-resistant aluminum-plastic film, which has a significant effect on improving battery performance. The two are used in combination, complementing each other, greatly enhancing the ability to resist electrolyte corrosion, and extending the service life and safety of the corrosion-resistant aluminum-plastic film.

[0028] In this embodiment, the thickness of the corrosion-resistant aluminum alloy outer layer 2 is 15 μm. The corrosion-resistant aluminum alloy outer layer 2 has a strong self-passivation ability, that is, when slightly scratched or worn, the exposed aluminum alloy substrate can quickly react with oxygen in the air to re-form an oxide film, thereby greatly enhancing the durability and reliability of the corrosion-resistant aluminum-plastic film in actual use.

[0029] In this embodiment, the connecting adhesive layer 4 is an epoxy resin layer, which has extremely high bonding strength and chemical resistance, and is environmentally friendly and non-toxic, reducing the impact on the environment, meeting the trend of sustainable development. The use of the connecting adhesive layer 4 improves the strength and durability of the bonding interface, ensuring the stable connection between 1 and 1.

[0030] It should be noted that the present utility model is a corrosion-resistant aluminum-plastic film for lithium batteries. During use, by setting the high-barrier base layer 1 and PVDC coating layers 6 at the upper and lower ends of the polyethylene film 5, both the high-barrier characteristics of the PVDC coating layer 6 are retained, and the good processing performance of the polyethylene film 5 is utilized, which is suitable for large-scale production. At the same time, the aluminum foil layer 7 can significantly improve the barrier performance, block light, oxygen and moisture, while maintaining good mechanical properties and cost-effectiveness; by setting the corrosion-resistant coating 3, the polytetrafluoroethylene coating 32 has excellent chemical inertness and corrosion resistance, and can effectively resist the erosion of the electrolyte. The alumina coating 31 not only provides excellent barrier properties, but also improves the electrochemical stability of the corrosion-resistant aluminum-plastic film, which has a significant effect on improving battery performance. The two are used in combination, complementing each other, greatly enhancing the ability to resist electrolyte corrosion, and extending the service life and safety of the corrosion-resistant aluminum-plastic film; by utilizing the strong self-passivation ability of the corrosion-resistant aluminum alloy outer layer 2, that is, when slightly scratched or worn, the exposed aluminum alloy substrate can quickly react with oxygen in the air to re-form an oxide film, thereby greatly enhancing the durability and reliability of the corrosion-resistant aluminum-plastic film in actual use.

[0031] The foregoing has shown and described the basic principles, main features, and advantages of the present utility model. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and all these changes and improvements fall within the scope of the present utility model claimed. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents.

Claims

1. A corrosion-resistant aluminum-plastic film for lithium batteries, comprising a high-barrier base layer (1) and a corrosion-resistant aluminum alloy outer layer (2), characterized in that: A corrosion-resistant coating (3) is provided at the lower end of the high-barrier base layer (1), and a connecting adhesive layer (4) for bonding the inner and outer sides is provided between the high-barrier base layer (1) and the corrosion-resistant aluminum alloy outer layer (2); The high barrier base layer (1) comprises a polyethylene film (5), wherein the upper and lower ends of the polyethylene film (5) are both provided with PVDC coating layers (6), and the ends of the two PVDC coating layers (6) away from the polyethylene film (5) are both provided with aluminum foil layers (7).

2. The corrosion-resistant aluminum-plastic film for lithium batteries according to claim 1, characterized in that: The upper end of the aluminum foil layer (7) located at the upper part is fixedly connected to the corrosion-resistant aluminum alloy outer layer (2) via a connecting adhesive layer (4).

3. The corrosion-resistant aluminum-plastic film for lithium batteries according to claim 1, characterized in that: The corrosion-resistant coating (3) comprises an aluminum oxide coating (31) and a polytetrafluoroethylene coating (32), wherein the polytetrafluoroethylene coating (32) is arranged at the lower end of the aluminum oxide coating (31), and the aluminum oxide coating (31) is arranged at the lower end of the lower aluminum foil layer (7).

4. The corrosion-resistant aluminum-plastic film for lithium batteries according to claim 1, characterized in that: The thickness of the corrosion-resistant aluminum alloy outer layer (2) is 15 um.

5. The corrosion-resistant aluminum-plastic film for lithium batteries according to claim 1, characterized in that: The connecting adhesive layer (4) is an epoxy resin layer.

Images