Challenges and prospectives of sodium-containing solid-state electrolyte materials for rechargeable metal batteries

The development of functional sodium-containing solid-state batteries (SSBs) depends on advancing solid-state electrolyte (SSE) materials with high ionic conductivity and exceptional chemical-electrochemical stability, which continues to pose significant challenges. This review provides a comprehensive overview of various sodium-containing SSEs, including oxides, sulfides, halides, and polymers. It begins with a brief historical perspective on the evolution of each SSE type, followed by an in-depth analysis of the mechanisms governing ion transport. We then evaluate the relative advantages and limitations of these SSEs, focusing on their suitability for integration into sodium-containing battery systems. The characterization techniques used to decouple and understand the complex processes within SSBs are also discussed. Furthermore, we highlight the most promising solutions to the current challenges in SSE development, with particular emphasis on recent advancements in interfacial design aimed at enhancing battery performance. Finally, we explore potential future directions for the development of high-performance sodium-containing SSEs.