Hard Carbon for Sodium‐Ion Batteries: From Fundamental Research to Practical Applications

Sodium-ion batteries (SIBs) have emerged as a promising technology for large-scale energy storage due to their unique performance characteristics and raw material accessibility. Among various anode materials, hard carbon (HC) stands out due to its high Na storage capacity, structural stability, and intrinsic safety. However, the structural complexity and heterogeneity of HC present ongoing challenges in understanding its structural models and Na storage mechanisms, impeding the rational design and performance optimization of HC-based anodes. This review provides a systematic overview of recent advances in HC for SIBs, beginning with an in-depth examination of representative structural models and the underlying…