Conductivity and dielectric behavior of lithium ion conducting gel polymer electrolyte

Abstract

Poly(vinylidene fluoride-hexafluropropylene) (PVdF-HFP) and poly(methyl methacrylate) (PMMA) gel polymer blend electrolyte system complexed with LiClO4 having different concentrations of propylene carbonate (PC) and diethyl carbonate (DEC) (1:1) plasticizers have been prepared using solution cast technique. Structural and surface morphology have been studied by X-ray diffraction and scanning electron microscopy analysis. Electrical conductivity has been carried out by electrochemical impedance spectroscopy in the temperature range 303 K to 343 K. A maximum electrical conductivity of 1.03 X 10-3 S cm−1 at 303 K has been achieved for the polymer blend gel electrolyte containing 60 wt% of PC:DEC plasticizers. Frequency dependent conductivity follows the Jonscher’s power law. The dielectric behavior has been analyzed using dielectric permittivity (ε*), tangent loss (tanδ) and electric modulus (M*) of the samples. Dielectric constant has been found to increase with addition of PC:DEC plasticizers.