First principles studies on operational mechanism in lithium sulfur and selenium batteries

Abstract

Widespread use in smart grid and electric transport applications, the energy density of battery needs to be improved beyond the scope of modern Li-ion battery. Based on the conversion reactions, Li-S and Li-Se systems hold great potential in improving energy density. That advantage, combined with low cost, suggests that this alternative technology shows promise for high-energy storage applications. However, the mechanism of conversion reactions is not fully understood, which results in low electronic and ionic conductivity and loss of active materials. Herein, we applied first principle calculation to gain deeper insight in the operational mechanism of Li-S and Li-Se battery. On top of that, we suggested new methods to identify and evaluate effective additive that can improve both kinetics and thermodynamics by controlling the intermediates.