Aluminum-plastic composite film for flexible packaging of lithium battery

Abstract

The invention discloses an aluminum-plastic composite film for flexible packaging of a lithium battery. The aluminum-plastic composite film comprises a wear-resistant layer, a first bonding layer, analuminum foil layer, a passivation layer, a second bonding layer having corrosion resistance and a heat sealing layer which are sequentially arranged from the outside to the inside, and the passivation layer comprises, by weight, 100 parts of acrylic resin, 5-15 parts of a chromium-containing compound, 1-5 parts of a phenyltrimethylsilane coupling agent, 1-5 parts of a titanate coupling agent and30-50 parts of water; and the second bonding layer having corrosion resistance includes, by weight, 100 parts of acid-modified polyolefin resin, 1-5 parts of an epoxy system curing agent, 1-5 parts offluorine-containing micro-powder, 10-20 parts of a cyclohexane solvent and 20-40 parts of a butanone solvent. The aluminum-plastic composite film has the advantages of obviously improved electrolyteresistance, stability in bonding among the first bonding layer, the aluminum foil layer, the passivation layer, the second bonding layer having corrosion resistance and the heat sealing layer, high deep-drawing intensity and long service life.

Description

technical field [0001] The invention relates to an aluminum-plastic composite film used for lithium battery flexible packaging. Background technique [0002] Aluminum-plastic film for lithium batteries is usually a laminated composite structure, mainly including outer layer material (protective layer), outer layer adhesive, middle layer (barrier layer), inner layer adhesive, inner layer material (heat seal layer) ), because LiPF6 in the lithium battery electrolyte can react with small molecule water to generate hydrofluoric acid (HF), causing corrosion of aluminum foil, battery short circuit, explosion or expansion, etc. key technologies. In order to improve the electrolyte corrosion resistance of the aluminum-plastic film, a large number of solutions for improving the inner layer of the aluminum-plastic film have appeared in the prior art. For example, Chinese Patent Application No. 2014104142891, the patent application for invention published on August 24, 2016, disclose...

AI Technical Summary

Problems solved by technology

Although the fluorine-containing film can improve the electrolyte resistance of the aluminum-plastic film, the electrolyte resistance is still poor and far from meeting people's requirements. Due to the characteristics of the fluorine material itself, it has low surface energy, surface hydrophobicity, and adhesion. Poor performance, so this aluminum-plastic film has the problems of poor drawability, poor corrosion resistance, and short service life