IONIC LIQUID-POLYMER GEL ELECTROLYTES

New rubbery gel electrolytes have been prepared from room temperature ionic liquids and poly(vinylidene fluoride)-hexafluoropropylene copoly mer [PVdF(HFP)]. The ionic liquids employed in these preparations were 1-ethyl-3-methylimidazolium salts of triflate (CF3SO3-) and BF4-. Whe n properly processed, the ionic liquid-PVdF(HFP) gels are freestanding , flexible films with room temperature conductivities ranging from 1.1 to 5.8 mS cm(-1). Because both the ionic liquids and the PVdF(HFP) ar e nonvolatile and are thermally stable, the gels can be operated at el evated temperatures without performance degradation. An ionic conducti vity of 41 mS cm(-1) was measured for a triflate ionic liquid-PVdF(HFP ) gel at 205 degrees C.