Is There a Ready Recipe for Hard Carbon Electrode Engineering to Enhance Na-Ion Battery Performance?

Hard carbon (HC) materials are commonly used as anode in Na-ion batteries. In most of the cases, their electrochemical performance is correlated only to physicochemical properties, and impact electrode additives (binders–conductive agent) electrolyte often neglected. this work, a systematic study performed understand role electrode/electrolyte engineering on HC initial Coulombic efficiency (iCE), specific capacity, cycle stability. Four HCs obtained by pyrolysis several biopolymers, i.e., cellulose (HC-Cell), chitosan (HC-Chs), chitin (HC-Cht), lignin (HC-Lig), used. The binder was found have an important performance, with PVDF resulting better than CMC. black additive had no significant CMC-based while it boosted PVDF-based electrodes. For optimized formulation (PVDF/carbon black), best NaPF6 1 EC:DEC delivered HC-Cell (83% iCE, 332 mAh g–1 at C/10, 97% retention). This attributed its large graphene interlayer space, high purity, low surface area. HC-Cht HC-Chs exhibited similar good (∼280 g–1) whereas use HC-Lig resulted iCE capacity fading overcycling due level impurities structure. could be overcome changing salt, using NaClO4 (76% retention) instead (52% Based results, properties binder/conductive additive. It demonstrated that careful combined proper selection tuned allowed all investigated achieving reasonable (up 83%), g–1), high-capacity retention (72–97% after 50 cycles).