Method for preparing solid-state lithium ion battery polymer electrolyte film by using ethylene-vinyl acetate copolymer as filler

The invention discloses a method for preparing a solid-state lithium ion battery polymer electrolyte film by using an ethylene-vinyl acetate copolymer as a filler, and relates to a polymer electrolyte film preparation method for improving the performance of a solid-state lithium ion battery. The invention aims to solve the problems of high interface impedance and poor cycling stability of a battery under high magnification of the existing solid electrolyte. The method comprises the following steps: 1, preparing a polymer electrolyte film matrix precursor solution; 2, preparing a polymer electrolyte film precursor solution; 3, preparing a polymer electrolyte film; and 4, assembling the solid-state lithium ion battery. The ethylene-vinyl acetate copolymer improves the rate capability of the electrolyte, forms physical constraint in a polymer electrolyte film so as to enhance the mechanical strength, and promotes the actual production and application. The invention is used in the field of lithium ion batteries.