Ionic Conductivity of LiSiON and the Effect of Amorphization/Heterovalent Doping on Li+ Diffusion

Abstract

The search for and design of suitable superior lithium ion conductors is a key process for developing solid state batteries. In order to realize a large range of applications, we researched the ionic conductivity of LiSiON, an example oxynitride mainly composed of elements with high abundance and a similar mixed anion size. Both its amorphous and heterovalent-doped phases were studied through density functional theory simulations. The Li+ ion diffusion behaviors and related properties are discussed. These elements are abundant in nature, and we found that amorphization or doping with P obviously enhanced the ionic conductivity of the system. General strategies to improve the kinetic properties of a candidate structure are presented, to help in the design of solid state electrolytes for lithium batteries.