Improvement of ionic conductivity of titanium dioxide incorporated PVDF-HFP/cellulose acetate electrolyte membrane

Abstract

This work aims to improve the lithium ion conductivity by incorporating titanium dioxide (TiO2) in Polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) and Cellulose acetate (CA) electrolyte membrane. The morphology of the prepared membrane was observed using Scanning Electron Microscope (SEM) and the ability of the membrane to uptake liquid electrolyte was also tested. The SEM results show that the electrolyte membrane has porous, interconnected network but the addition of TiO2 resulted in a reduction in porosity. Despite reduced porosity, the electrolyte uptake of PVDF-HFP+CA+TiO2 is the highest among others with value up to 287.5%, this increase is due to the improvement in the amorphous phase. The ionic conductivity increases by 21.29% compared to PVDF-HFP electrolyte membrane with the addition of TiO2. The generation of more mobile lithium ion and prevention of crystallization of polymer through Lewis acid-base reaction leads to improvement in ionic conductivity.