We found five materials with fast ionic diffusion, some in the range of the well-known superionic conductor Li10GeP2S12, such as for example the Li-oxide chloride Li5Cl3O, the doped halides Li2CsI3, LiGaI4, and LiGaBr3, or the Li-tantalate Li7TaO6. In addition, we found 40 materials that show significant diffusion at 1000 K, though they will need to be investigated more thoroughly before their suitability can be determined. All of these potential fast-ionic conductors could be studied further, in more detail, by experiment and simulation, and could result in new fast-ionic conductors or even electrolytes for next generation solid-state Li-ion batteries. Our data could also serve to search for descriptors of fast ionic conduction, which would be of significant interest to the community.

This work benefits society by identifying inorganic solid-state lithium-ionic conductor compounds that could be used as electrolytes to mitigate or overcome the severe safety challenges posed by the use of volatile and flammable liquid or polymer electrolytes in today’s Li-ion batteries. Complete replacement of the liquid electrolyte by a solid ceramic would result in an all-solid-state Li-ion battery, highly beneficial due to the higher electrochemical stability of inorganic electrolytes, compared to their organic counterparts.