Molecular Analysis of Electrolyte for Lithium-Air Batteryby MD Simulations

Abstract

The aqueous lithium-air battery is receiving considerable research attention because of its high theoretical energy density. However, high-power discharge has not been achieved. Because ion transport phenomena in the battery determine current density, molecular interpretation of the electrolyte is required to improve the battery performance. In order to clarify the fundamental mechanism, the present study investigated LiCl electrolyte by using molecular dynamics simulation. The results showed that hydrated structures of Cl- and Li+ were reproduced successfully. Although the LiCl solution is categorized as strong electrolyte, Cl^- and Li⁺ existed with forming ion-pair. Formation of cluster structure was also suggested under higher concentration condition. As a result, the reduction of self-diffusion coefficient caused by the increasing of hydration radius was investigated.