Conductivity studies of LiCF3SO3-doped and DMF-plasticized PVDF-based solid polymer electrolytes

Room temperature ionic conductivity measurements show that the conductivity of polyvinylidene fluoride (PVDF)-based solid polymer electrolyte films depends on the concentration of the doping salt and the plasticizer. The highest conductivity for the doped PVDF system is 3.40 × 10–5 S cm–1 and for the plasticized system is 1.30 × 10–4 S cm–1. Conductivity–temperature dependence studies on the pure, doped and plasticized PVDF systems show that the sudden change in the slope of Arrhenius plots corresponds to the glass transition of PVDF as inferred from tan δ-temperature plots. The decrease in ionic conductivity in the high-temperature range can be attributed to the transformation of PVDF from the polar to nonpolar form as shown by X-ray diffraction studies. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)