Solid polymer electrolytes: attempts to improve conductivity

To attempt to improve conductivity in solid polymer electrolytes, we have examined several approaches. These include the preparation of new polymer-salt complexes, the use of soluble additives that would provide conduction pathways and the use of certain insoluble additives that might also tend to improve electrical properties. In this paper we report on these attempts and the effect that such materials have on conductivities. Metal-ion complexes of poly(vinyl acetate), a polyphosphinate, and a crown ether containing polymer were prepared and evaluated. All exhibited significant conductivity but the best result was obtained when the polymeric crown ether was combined with poly(vinylene carbonate). Conductivity near 10^-3 Scm^-1 close to room temperature was observed. Silver(I) and mercury (II) salts were also shown to form conducting complexes with poly(ethylene oxide) with the silver complexes having about 100 times better conductivities than the mercury complexes. Addition of high surface area materials, for example silica gel, microcrystalline cellulose and carbon black, to polymeric electrolytes did not improve conductivities.