Microstructure and adhesion properties of cerium conversion coating modified with silane coupling agent on the aluminum foil for lithium ion battery

摘要

In this study, a conversion coating was deposited on the surface of aluminum (Al) foil used as the packaging foil of lithium ion battery by immersion in cerium (Ce) conversion solution modified with or without γ-(methacryloxypropyl) trimethoxy silane (KH570). The morphology, composition and wettability of the conversion coating were investigated by scanning electron microscopy, energy dispersive spectroscopy, atomic force microscopy and contact angle measurement. In addition, a six-layered packaging film was prepared by hot pressing using casting polypropylene as the inner layer and maleic anhydride grafted polypropylene (PP-g-MAH) as the inner adhesive. The adhesion and heat-sealing properties of untreated, Ce treated and KH570 modified Ce treated (KH570-Ce) Al foils were characterized by T-peeling test. The results show that a homogeneous and hydrophobic coating is formed on the surface of KH570-Ce treated Al foil, and the adhesion between the inner adhesive and the KH570-Ce treated Al foil substrate is greatly improved because of the synergistic effect of silane and Ce-containing conversion coating.