Recent Advances and Prospects of Cathode Materials for Sodium‐Ion Batteries

TLDR

Sodium‑ion batteries are attractive for energy storage because of abundant, low‑cost Na, yet they suffer from low specific energy, short cycle life, and limited power due to the heavy Na⁺ ion, making cathode material design critical for improving performance. This review summarizes recent advances and prospects of inorganic and organic cathode materials for sodium‑ion batteries. Layered transition‑metal oxides deliver about 600 Wh kg⁻¹, porous Na₃V₂(PO₄)₃/C nanomaterials retain nearly 100 % capacity after 1000 cycles, and emerging materials such as amorphous NaFePO₄ and pteridine derivatives exhibit attractive electrochemical properties for future SIB applications.

Abstract

Sodium‐ion batteries (SIBs) receive significant attention for electrochemical energy storage and conversion owing to their wide availability and the low cost of Na resources. However, SIBs face challenges of low specific energy, short cycling life, and insufficient specific power, owing to the heavy mass and large radius of Na + ions. As an important component of SIBs, cathode materials have a significant effect on the SIB electrochemical performance. The most recent advances and prospects of inorganic and organic cathode materials are summarized here. Among current cathode materials, layered transition‐metal oxides achieve high specific energies around 600 mW h g −1 owing to their high specific capacities of 180–220 mA h g −1 and their moderate operating potentials of 2.7–3.2 V (vs Na + /Na). Porous Na 3 V 2 (PO 4 ) 3 /C nanomaterials exhibit excellent cycling performance with almost 100% retention over 1000 cycles owing to their robust structural framework. Recent emerging cathode materials, such as amorphous NaFePO 4 and pteridine derivatives show interesting electrochemical properties and attractive prospects for application in SIBs. Future work should focus on strategies to enhance the overall performance of cathode materials in terms of specific energy, cycling life, and rate capability with cationic doping, anionic substitution, morphology fabrication, and electrolyte matching.