A new strategy for enhancing the room temperature conductivity of solid-state electrolyte by using a polymeric ionic liquid

Abstract

An ether-functionalized polymeric ionic liquid poly(methyl methacrylate-1-vinyl-3-methoxyl-ethyl-imidazolium bis(trifluoromethanesulfonyl)imide) P(MMA-co-VIm(1O2)) (TFSI) polymeric ionic liquid (PIL) was successfully synthesized, characterized, and used as polymer matrix. The performances of solid polymer electrolytes membrane were measured through blending with poly(vinylidene fluoride-cohexafluoropropylene) (PVDF-HFP) and 1-propyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl) imide ([Pyr13][TFSI]). The ionic conductivity of polymer electrolytes was optimized up to 5.10 × 10−4 S cm−1 at 25 °C, and a wide electrochemical window of 5.23 V vs Li/Li+ could be obtained. Moreover, the polymer electrolytes showed excellent cycle performance for Li/LiFePO4 cell at both 25 °C and 60 °C, demonstrating the capability of being a promising candidate for the application of solid-state lithium-ion batteries.