Inorganic Sodium Solid Electrolytes: Structure Design, Interface Engineering and Application

All-solid-state sodium batteries (ASSSBs) are particularly attractive for large-scale energy storage and electric vehicles due to their exceptional safety, abundant resource availability, and cost-effectiveness. The growing demand for ASSSBs underscores the significance of sodium solid electrolytes; However, the existed challenges of sodium solid electrolytes hinder their practical application despite continuous research efforts. Herein, recent advancements and the challenges for sodium solid electrolytes from material to battery level are reviewed. The in-depth understanding of their fundamental properties, synthesis techniques, crystal structures and recent breakthroughs is presented. Moreover, critical challenges on inorganic sodium solid electrolytes are emphasized, including the imperative need to enhance ionic conductivity, fortifying interfacial compatibility with anode/cathode materials, and addressing dendrite formation issues. Finally, potential applications of these inorganic sodium solid electrolytes are explored in ASSSBs and emerging battery systems, offering insights into future research directions. All-solid-state sodium batteries (ASSSBs) are particularly attractive for large-scale energy storage due to their benefits in safety, abundant resource, and cost-effectiveness. The inorganic sodium solid electrolytes have become the most promising ion conductors due to their nonflammable nature and high ionic conductivities. Meanwhile, the existing application of inorganic sodium solid electrolytes in different devices delivers bright prospect of the electrolytes. image