Phase behaviors of solid polymer electrolytes/salt system in lithium secondary battery by group-contribution method: The pressure effect

Abstract

A new group-contribution model based on the modified double-lattice theory with the free volume effect is developed and applied to describe phase-behaviors of solid polymer electrolyte/salt system with various pressures. The proposed group-contribution model includes the van der Waals energy contribution from dispersion and polar forces. Our result show that an eutectic point moves toward higher T-m and lower weight fraction of salt with increasing pressure. Quantitative description according to the proposed model is in good agreement with the experimentally observed transition temperature of a given system.