Variable-Temperature 7Li Solid-State NMR Study to Determine Li-Ion Mobility and Its Correlation with Conductivity in Polymer Electrolytes Based on P(VdF-HFP)/ P(EO-EC) Blends for Li-Ion Secondary Batteries

摘要

n a previous study1, in order to alleviate the problems inevitably caused by the organic solvent leakage and evaporation in the gel-type electrolytes, we reported the novel solvent-free polymer electrolytes based on porous poly(vinyliene fluoride-co-hexafluoropropylene) [P(VdF-HFP)]/poly (ethylene oxide-co-ethylene carbonate) [P(EO-EC)] blend membranes with pores immersed by P(EO-EC). A salient conclusion of our results indicated the ionic conductivity of the electrolytes with Arrhenius temperature dependence reached a maximum value of ca. 4?0~(-5) S cm-1 at the room temperature for the E-V6E4 electrolyte prepared by the blend composition of 60/40 of P(VdF-HFP)/P(EO-EC). It is noteworthy that E-VxEy denotes the Electrolyte of P(VdF-HFP)/P(EO-EC) porous matrix (x/y by wt%) immersed by P(EO-EC)/LiCF-3SO-3 inside pores.