Ion-conductive polymer electrolytes based on poly(ethylene carbonate) and its derivatives

Ion-conductive polymer electrolytes are remarkable materials that have recently been proposed for use as flexible solid electrolytes in next-generation energy storage devices. In particular, the author has proposed the synthesis of novel polymer electrolytes with very high ionic conductivities and the essential properties of polymeric materials. This review describes the synthesis of alternating copolymers of CO2 with epoxides and their application as novel ion-conductive polymers in the place of typical polyether-based systems. The Li salt electrolytes of poly(ethylene carbonate) (PEC) and of other polycarbonates with different side groups exhibit unique ion-conductive properties, such as increasing conductivity with higher salt concentrations, very high Li transference numbers and good electrochemical stability. The Li-ion conductivity of a PEC-lithium bis(fluorosulfonyl) imide LiFSI electrolyte was estimated to be greater than 10(-4) S cm(-1), and excellent battery performance of this material was also demonstrated at room temperature.