Effect of PEO addition on the electrolytic and thermal properties of PVDF-LiClO4 polymer electrolytes

Polymer electrolyte membranes comprising poly(vinylidene fluoride), PVDF, Poly(ethylene oxide), PEO, and LiClO4 were prepared and characterised with respect to ambient temperature ionic conductivity (sigma(i)). The miscibility studies were performed using XRD and DTA in order to best understand the chemical compatibility between PVDF and PEO. Structural characterisation was carried out on the polymer electrolyte thin film membranes using XRD. The ac-conductivity studies were performed to evaluate the ambient temperature conductivity of the polymer electrolyte membranes. The conductivity and mechanical integrity of PVDF:LiClO4 polymer electrolyte complex were studied as a function of PEO concentration. The addition of PEO into PVDF:LiClO4 complex enhances the room temperature conductivity and mechanical stability of the thin film electrolyte membrane. The maximum conductivity at 30 degrees C was found to be 2.62 x 10(-5) S cm(-1) for (PVDF-LiClO4):PEO (80:20) w/o which is two orders of magnitude higher compared to PVDF-LiClO4 system.