Design of Solid Electrolytes with Fast Ion Transport: Computation-Driven and Practical Approaches

For next-generation all-solid-state metal batteries, the computation can lead to the discovery of new solid electrolytes with increased ionic conductivity and excellent safety. Based on computational predictions, a new proposed solid electrolyte with a flat energy landscape and fast ion migration is synthesized using traditional synthesis methods. Despite the promise of the predicted solid electrolyte candidates, conventional synthetic methods are frequently hampered by extensive optimization procedures and overpriced raw materials. It is impossible to rationally develop novel superionic conductors without a comprehensive understanding of ion migration mechanisms. In this review, we cover ion migration mechanisms and all emerging computational approaches that can be applied to explore ion conduction in inorganic materials. The general illustrations of sulfide and oxide electrolyte structures as well as their fundamental features, including ion migration paths, dimensionalities, defects, and ion occupancies, are systematically discussed. The major challenges to designing the solid electrolyte and their solving strategies are highlighted, such as lattice softness, polarizability, and structural disorder. In addition to an overview of recent findings, we propose a computational and experimental approach for designing high-performance solid electrolytes. This review article will contribute to a practical understanding of ion conduction, designing, rapid optimization, and screening of advanced solid electrolytes in order to eliminate liquid electrolytes.