Highly conducting solid electrolytes based on poly (ethylene oxide‐<i>co</i>‐propylene oxide)

Abstract

Abstract The conducting properties of solid electrolytes comprising random poly(ethylene oxide‐ co ‐propylene oxide) (of 84 : 16 monomer units mole ratio) and lithium, sodium, potassium, cesium, and rubidium salts have been studied. The systems containing some lithium or sodium salts achieved conductivity levels as high as 10 −5 –10 −4 S/cm at ambient temperature and greater than 10 −3 S/cm at 100°C. However, the systems with rubidium and cesium salts exhibit conductivities a few orders of magnitude smaller. DSC studies show that the electrolytes studied are characterized by a high content of an amorphous phase (95–100%). It is suggested that the copolymer exhibits lower complexing abilities than that of poly(ethylene oxide), which results in a higher flexibility of electrolytes containing small cations and poor dissociation of the salts having large cations. © 1995 John Wiley &amp; Sons, Inc.