Positive electrode current collector and preparation method and application thereof

Abstract

The invention discloses a positive electrode current collector and a preparation method and an application thereof. The positive electrode current collector is of a multilayered structure and comprises a plastic thin film, wherein the upper and lower surfaces of the plastic thin film are coated with a bonding force enhancement layer, an aluminum metal coating layer and an anti-oxidization layer in sequence. The preparation method comprises the steps of coating the bonding force enhancement layer, the aluminum metal coating layer and the anti-oxidization layer through an evaporation film-coating process in sequence. The application of the positive electrode current collector mainly refers to an application in a lithium ion battery. By virtue of the positive electrode current collector, light weight of the battery can be realized, energy density can be improved, the aluminum coating layer does not fall off easily, and easy oxidization can be avoided.

Description

technical field [0001] The invention relates to a positive current collector, its preparation method and application. Background technique [0002] The traditional lithium-ion battery positive current collector is aluminum foil. With the development of lithium battery technology, high energy density, light weight and flexibility of lithium ion batteries have become people's pursuit. Thinning aluminum foil can reduce the weight of lithium-ion batteries and increase energy density. However, due to the limitations of the preparation technology, it is difficult to reduce the thickness of the aluminum foil (currently the aluminum foil can be mass-produced to 8μm); in addition, after the aluminum foil is thinned, the mechanical strength decreases, resulting in a decrease in processing performance, so a new "thinning technology" is needed. [0003] In the prior art, aluminum is plated on plastic (such as PET) as a current collector to increase the energy density of the battery, r...

AI Technical Summary

Problems solved by technology

However, the thickest thickness of its aluminum plating is up to 2.0 μm (a certain thickness is required to achieve satisfactory conductivity), which is much thicker than the thickness of the traditional packaging material aluminized film coating, and the thicker the coating, the better the aluminum coating. The easier the layer comes off the plastic

[0004] In addition, the surface of the aluminum foil needs anti-oxidation treatment, because the aluminum foil is directly in contact with the positive electrode material, and after a long time, it will be corroded by the electrolyte, thereby reducing the service life of the lithium-ion battery

We found that after direct aluminum plating on the plastic, the traditional anti-oxidation method is easy to cause the aluminum coating to fall off

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