Highly conducting solid electrolytes based on poly (ethylene oxide‐co‐propylene oxide)

The conducting properties of solid electrolytes comprising random poly(ethylene oxide-co-propylene oxide) ( 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