Exploring lithium salt solution in sulfone and ethyl acetate-based electrolytes for Li-ion battery applications: a molecular dynamics simulation study

Abstract

The design of lithium-ion batteries (LIBs) by introducing novel electrolytes is an interesting research topic in electrochemistry, due to the necessity of using LIBs to fight against the energy crisis and environmental pollution. In this study, we present a novel electrolyte made by adding ethyl acetate (EA) to a mixture of ethyl methyl sulfone (EMS) solvent and lithium hexafluorophosphate (LiPF₆) salt. The resulting mixture presents the desired characteristics of a suitable electrolyte for application in LIBs. By employing molecular dynamics (MD) simulations, characteristics such as the diffusion coefficient and ionic conductivity, as well as structural properties for different molar ratios of individual constituents of the electrolyte mixtures, are evaluated. It is found that EMS molecules play a critical role in ion pair separation and the coordination number of PF₆⁻ around Li⁺ is evaluated. The simulation result is obtained for the salt concentration range of 0.485 to 1.643 mol l⁻¹, demonstrating a significant reduction in ionic conductivity. Also, the effect of temperature variation from 260 K to 360 K on electrolyte properties is investigated and the activation energy of Li⁺ is obtained using the Arrhenius relation.