Recent progress of Mn-based NASICON-type sodium ion cathodes

Sodium-ion batteries have attracted extensive concern and research for smart grids and large-scale energy storage systems owing to the low cost and high natural abundance of Na resource. Selecting appropriate electrode materials is beneficial to the development and research of SIBs. Compared with typical NASICON-structure Na₃V₂(PO₄)₃, Mn-based NASICON-type cathodes for sodium-ion batteries reveal highly attractive application prospects due to their high earth-abundance and rich valence states of elemental Mn. Besides, the adjustable merit of NASICON structure endows a big family of Mn-based material system with enriched compositions. In this review, Mn-based NASICON-type sodium ion cathodes are briefed to provide a comprehensive overview of their recent advance. The structure, electrochemical reaction mechanism and properties are demonstrated. Moreover, the critical issues happened to lots of Mn-based materials, such as Mn dissolution, Jahn–Teller distortion, the influence of liquid electrolyte, etc., are discussed. At last, perspectives and challenges about the future development of Mn-based NASICON-type cathodes are presented as well. We believe that this review can serve as a reference for preparing Mn-based NASICONs toward the utilization of both nonaqueous and aqueous rechargeable devices beyond sodium ion batteries.