Coating materials and processes for cathodes in sulfide-based all solid-state batteries

This short review focuses on critical issues related to the cathode/solid-electrolyte (SE) interface in all solid-state batte-ries (SSBs), including chemical instability, space-charge layer, and mechanical failure. Moreover, we reviewed recent R&D efforts to solve the issues by passivating the cathode in-terfaces using various materials (e.g. metallic oxides, carbon-ates, phosphates, halides, and polymers) and coating processes (e.g. sol-gel, dry coating, and atomic layer deposi-tion). Finally, future perspectives have been outlined to un-derstand fundamental electro-chemo-mechanical reactions occurring through coating layers to improve the performances of SSBs in the future.