Li+ and Na+ ion superionic conductors for all-solid-state batteries

Abstract

Recently, all-solid-state batteries using inorganic solid electrolytes (SEs) have emerged because of their ultimate safety as well as the potential of high energy density. Particularly, bulk-type all-solid-state batteries are highly promising becausethick composite electrodes can be fabricated by scalable wet-slurry process. Among various SE candidates, sulfide materials are suitable for bulk-type all-solid-state batteries owing to their exceptionally high ionic conductivities (max. 10-2S cm-1) and deformability that allows two-dimensional contacts with active materials by simple cold-pressing process. While the most previous R&D efforts focused on high ionic conductivity of SEs, there are also other important aspects that should be addressed to develop high-performance bulk-type all-solid-state batteries; new synthesis protocols, chemical stability such as air stability, fabrication of sheet-type electrodes. Recently, our group reported solution-based processing of SE materials for Li and Na ion SEs. And the solution-processing of SEs was demonstrated to apply for the coating on active materials and infiltration into conventional lithium-ion battery electrodes. In this presentation, the relevant results on all-solid-state Li and Na-ion batteries will be presented.