Abstract: A new kind of polymeric electrolyte film with low glass transition temperature and high room temperature conductivity was prepared by plasticizing the complex of poly(ethy-lene oxide-propylene oxide-allyl glycidyl ether)and LiClO₄ with dimethoxy poly(ethyleneglycol)(PEGDME). The effect of plasticizer content on the conductivity of electrolytewas studied. The plasticized electrolyte films showed both a good thermal stability and a good mechanical property. A room temperature conductivity as high as 2?10^-4Scm^-1 was obtained for film with 60%(vol)plasticizer. The mclecular weight of the plasticizer as a function of conductity was discussed as well.

Key words: polyethylene glycol, polymer electrolyte, conductivity, lithium perchlorate