EFFECT OF CONCENTRATION AND NATURE OF LITHIUM SALT ON CHARACTERISTICS OF GEL ELECTROLYTES DMSO-PVDF-LiAn

Abstract

The results of the study of electrolytes based on gel solutions of DMSO-PVDF-lithium salt with concentrations up to 0.05 m.f. and above 0.1 m.f. are presented. It is shown that the conductivity of electrolytes is close to the conductivity of lithium salt solutions in pure DMSO and obeys the Arrhenius equation in the studied range of temperatures and concentrations. The calculated activation energies for electrolytes with a salt concentration of up to 0.05 m.f. are 14–15.4 KJ/Mol, and for electrolytes with a salt concentration above 0.1 m.f. - 16.9–20.6 KJ/Mol indicate a fast ion transfer, which in more concentrated solutions is inhibited by an increase in their crystallinity. The analysis of the equivalent circuit models of the Li-Li systems electrochemical impedance spectra showed the tendency of electrolytes to form capacitive elements at the lithium electrode-electrolyte interface. It was recognized the presence of semi-infinite diffusion in LiClO4 and LiIm with salt concentration of 0.05 m.f., due to the imperfection of the film formed on the electrode surface. The efficiency of using DMSO-PVDF-lithium gel electrolytes on steel and platinum electrodes was analyzed by voltammograms.