The investigation of deep eutectic electrolyte based on Choline Chloride: Ethylene glycol in 1:3 M ratio and lithium hexafluorophosphate salt for application in Lithium-Ion batteries

Abstract

The current work presents an experimental measurement of density and viscosity of binary deep eutectic electrolyte (DEEs) consisting of choline chloride/ethylene glycol in 1:3 M ratio and Lithium hexafluorophosphate salt in eight concentrations and the temperature ranges of 298–318 K. The computational approach is also applied in the characterization of the transport properties (self-diffusion coefficient, viscosity, and ionic conductivity) of the mixtures in the temperature ranges of 298–398 K. Our investigation showed that the diffusion coefficients of each component in the mixture and ionic conductivities of solutions are decreasing by increasing the salt concentration. Moreover, the viscosity of the deep eutectic solvent increases by adding the LiPF6 to the mixture. This information would enable one to rationalize the observed ionic conductivity behavior of the solution and assist in the formulation of novel DEEs with improved properties. Insights from the structural investigation such as radial and spatial distribution function can give additional intuition about the microstructure of mixture. © 2022 Elsevier B.V.