Structure and ionic conductivity in evaporated thin films of poly(ethylene oxide) complexed with LiCF3SO3

Thin polymer electrolyte films are formed by evaporating a suitable mixture of poly(ethylene oxide) (PEO) and LiCF3SO3. The films are found to exhibit a considerably high ionic conductivity of about 3×10−2 S/m at room temperature. The evaporated films are partially composed of a structure similar to that of the molten state of PEO, the melting point being diffuse in the range -20 ∼ 50°C. The conductivity enhancement at room temperature in the evaporated films can probably be attributed to the molten state structure regions.