Advanced Cellulose‐Derived Hard Carbon as Anode for Sodium‐Ion Batteries: Mechanisms, Optimization, and Challenges

Abstract Hard carbon materials are regarded as the most promising negative electrode materials for commercial sodium‐ion batteries. As the most abundant bioresource in nature, cellulose has unique fiber structure and multifunctional groups, is considered to be appropriate precursor for the preparation for hard carbon. The present review comprehensively elaborates on the mechanism of sodium storage and different preparation methods of cellulose‐derived hard carbon, explores different microstructures of cellulose‐derived hard carbon for sodium storage and electrochemical performance in sodium ion batteries, proposes corresponding treatment methods to improve the electrochemical performance targeted at precursors of cellulose‐based materials. This review also presents an update on development of electrochemical performance for cellulose‐derived hard carbon in SIBs, figures out the achievements and shortcomings in the advanced study of cellulose‐derived hard carbon. Meanwhile, the relationship between electrochemical performance and microstructure of cellulose‐derived hard carbon obtained from different precursors and preparation methods is systematically summarized through theoretical calculations and characterization analyses. Additionally, the critical issues, challenges, and trends of cellulose‐derived hard carbon in SIBs for commercialization in future are discussed.