METHOD OF MANUFACTURING A MULTI-COMPONENT SEPARATOR FILM WITH ULTRA HIGH MOLECULE WEIGHT POLYETHYLENE FOR LITHIUM SECONDARY BATTERY AND A MULTI-COMPONENT SEPARATOR FILM FOR LITHIUM SECONDARY BATTERY THEREFROM

摘要

A method for manufacturing a flame retardant multicomponent separator for a lithium secondary battery containing an ultrahigh molecular weight polyethylene is provided to improve the affinity with vinylidene fluoride, thereby enhancing ion conductivity and mechanical strength. A method for manufacturing a flame retardant multicomponent separator for a lithium secondary battery comprises the steps of mixing a vinylidene fluoride-based polymer, an ultrahigh molecular weight polyethylene and a high density polyolefin by using a compatibilizer; dissolving the mixture in liquid paraffin; extruding and casting the dissolved mixture to prepare a polymer sheet; biaxially stretching the cast film to prepare a separator; washing the biaxially stretched separator with a volatile solvent to remove liquid paraffin; and heat setting the washed separator.