Study on PVDF-HFP Based Nanocomposite Polymer Electrolytes for Energy Storage Devices Dispersed with Various Nano-Fillers

Abstract

Using the solution casting method, various compositions of nanocomposite polymer electrolyte (NCPE) films were successfully synthesised, including  Polyvinylideneflouride-co-hexafluoropropylene (PVDF-HFP) as a host, Magnesium chloride (MgCl₂) as an ionic salt and various concentrations of nanosized ceramic fillers -TiO₂, MgO, ZnO and Al₂O₃. Effect of dispersion of various ceramic filler in SPE on ionic conductivity of SPE has been discussed. The best bulk conductivity (\(\sigma \)) achieved at room temperature for optimum conducting composition (OCC) of solid polymer electrolyte is 4.69x10^-7 S/cm-phase-I^st. Further on addition of filler-phase II^nd, conductivity increased and achieved highest for composition i.e. PVDF-HFP: MgCl₂: ZnO (70:30:3) of NCPE is 1.25x10^-5 S/cm and from temperature dependence study we got highest \(\sigma \) for OCC of NCPE at 110 ⁰C is 1.24x10^-4 S/cm. Impedance Spectroscopy was used to measure the electrical properties of all samples in the frequency range 42Hz-5MHz and the temperature range 30 -110⁰C. To characterise the structural properties of these NCPE films, X-ray Diffraction (XRD) was used. The ion transport number t_ion \(\sim\)0.99 for OCC of NCPE system obtained by Wagner’s dc polarization technique.