Recent Advances in Stabilization of Sodium Metal Anode in Contact with Organic Liquid and Solid‐State Electrolytes

Sodium (Na) metal is considered as the promising anode for next‐generation high‐energy‐density Na‐metal batteries owing to its highest specific capacity and lowest electrochemical potential among all Na‐based anode candidates. However, the Na metal anode suffers from considerable volume change, nonuniform Na deposition, and an unstable electrode–electrolyte interface, which result in rapid capacity fade and poor cycling stability, hampering its practical application. To tackle aforementioned issues, many strategies have been developed to accommodate and guide Na nucleation/growth as well as stabilize the interface, including structure stabilization by applying 3D host materials, electrolyte modification and interface engineering to form stable interfaces and guide the Na deposition, etc. The present review is intended as a guideline through the fundamental challenges affecting the performance of Na metal anodes along with corresponding mitigation strategies. Moreover, the specific mechanisms for stabilizing Na metal anodes are discussed in detail. Apart from the stabilization of the Na metal anode in contact with liquid electrolytes, attention has also been paid to the review of stabilization of the Na metal anode in contact with solid‐state electrolytes. Furthermore, unresolved challenges and promising perspectives for stable Na metal anodes in practical applications are presented.