Poly(vinylidene fluoride-hexafluoropropylene) (PVdF-HFP) based composite electrolytes for lithium batteries

The composite polymer electrolyte (CPE) membranes, comprising of poly(vinylidene fluoride-hexafluoropropylene) (PVdF-HFP), aluminum oxyhydroxide, (AlO[OH]n) of two different particle sizes 7 μm/14 nm and LiN(CF3SO2)2 as lithium salt were prepared using solution casting technique. The prepared membranes were subjected to XRD, impedance spectroscopy, compatibility and transport number studies. The incorporation of nanofiller greatly enhanced the ionic conductivity and the compatibility of the composite polymer electrolyte. Also LiCr0.01Mn1.99O4/CPE/Li cells were assembled and their charge–discharge profiles have been made at 70 °C. The film which possesses nanosized filler offered better electrochemical properties than those with micron sized filler. The results are discussed based on Lewis acid–base theory.