Critical interface between inorganic solid-state electrolyte and sodium metal

Abstract: With widening applications in next-generation energy storage systems, rechargeable secondary batteries with enhanced safety and energy density are imperative for technological advancements. All-solid-state sodium batteries can be a promising low-cost and high-energy-density candidate, provided that stable cycling of the energy-dense Na metal anode can be achieved. However, the interface between Na metal and solid-state electrolyte remains a challenging problem. Here we comprehensively review various physical and chemical properties of different types of sodium-based solid-state electrolytes including sodium β-alumina, Na super ionic conductors (NASICON), chalcogenides, perovskites, complex hydrides and antiperovskites, and discuss some critical common factors that affect the Na/electrolyte interface stability. We also summarize the state-of-art strategies to engineer the interface for better electrochemical performances.