Ionic transport in P(VDF-HFP)–PMMA–LiCF3SO3–(PC + DEC)–SiO2 composite gel polymer electrolyte

Composite gel polymer electrolytes composed of poly(vinylidene fluoride-co-hexafluoropropylene) P(VDF-HFP) and polymethylmethacrylate PMMA polymers, PC + DEC as plasticizer and LiCF3SO3 as salt and fumed silica as filler have been synthesized by solvent casting technique with varying plasticizer–filler ratio systematically. Films of thickness in the range of 40–70 μm were characterized by a.c. impedance measurements in the temperature range 303 K to 373 K. Addition of filler to the polymer electrolyte was found to result in an enhancement of the ionic conductivity. A maximum electrical conductivity of ∼1 × 10−3 S/cm at 303 K and ∼2.1 × 10−3 S/cm at 373 K has been achieved with the dispersion of the SiO2. FTIR spectral studies confirmed the polymer–salt interaction. XRD patterns exhibit the increased amorphicity in the blended composite gel polymer electrolytes. Scanning electron micrograph shows the dispersion of SiO2 particle in the polymer electrolyte.