Electrochemical properties of gel polymer electrolytes prepared by poly(vinyl acetate) copolymers

We have studied the electrochemical properties of gel polymer electrolytes prepared by poly(vinyl acetate) copolymers. All of the gel polymer electrol ytes showed elasticity, free standing property and ionic conductivities ove r 0.5 mS/cm in certain compositions. The vinyl acetate moiety could increas e the affinity of copolymer toward carbonate-based liquid electrolytes, but silica was needed to prepare elastic and stable gel polymer electrolyte. T he effect of silica on the different types of the copolymer matrix is discu ssed in detail. The gel polymer electrolyte prepared by using poly(methyl m ethacrylate-co-vinyl acetate)(PMVC) especially showed stable ionic conducti vity over 1 x 10(-3) S/cm with a reasonable mechanical strength and electro chemical stability window above 4.8 V among the gel polymer electrolytes th at tested in this study.