Recent progress in sulfide-based solid electrolytes for Li-ion batteries

Abstract Sulfide-based ionic conductors are one of most attractive solid electrolyte candidates for all-solid-state batteries. In this review, recent progress of sulfide-based solid electrolytes is described from point of view of structure. In particular, lithium thio-phosphates such as Li 7 P 3 S 11 , Li 10 GeP 2 S 12 and Li 11 Si 2 PS 12 etc. exhibit extremely high ionic conductivity of over 10 −2  S cm −1 at room temperature, even higher than those of commercial organic carbonate electrolytes. The relationship between structure and unprecedented high ionic conductivity is delineated; some potential drawbacks of these electrolytes are also outlined.