Developing High‐Performance Metal Selenides for Sodium‐Ion Batteries

Abstract Sodium‐ion batteries (SIBs) show tremendous potential for large‐scale energy storage systems due to the high abundance of sodium resources and potentially low cost. Among the discovered anode materials for SIBs, metal selenides with large theoretical capacities are considered as a promising candidate. Nevertheless, metal selenide‐based anodes are trapped by poor ionic/electronic conductivity, low initial Coulombic efficiency, and drastic volume changes during the (de)sodiation process. Herein, the differences in sodium‐storage mechanisms of different metal selenides are first analyzed. Subsequently, the specific challenges and corresponding modification strategies (such as nanostructure design, carbon modification, potential window regulation, electrolyte optimization, and constructing heterostructures) for metal selenides as SIB anodes are discussed in detail, and recent advances are also presented. Finally, the potential research directions of metal selenides in SIBs are comprehensively reviewed. It is believed that this review can provide constructive comments on the optimization and large‐scale application of high‐performance metal selenide‐based anode for SIBs.