Influence of Hard/Soft Carbon Ratio in Composite Anodes for Enhanced Performance in Sodium‐Ion Battery

Abstract Sodium‐ion batteries (SIBs) are an emerging next‐generation technology for sustainable energy storage. In this study, the synthesis and performance of carbon anode materials for SIBs, produced via direct co‐carbonisation of textile waste‐derived hard carbon (HC) and pitch‐derived soft carbon (SC) at various ratios, were investigated. It was found that, as the ratio of HC increased, the rate capacity of the composite carbon anode improved, with the best performing composite anode exhibiting a specific capacity of 334 mAh g −1 at a current density of 50 mA g −1 which exceeded the specific capacity of 100 %HC and 100 %SC. The co carbonisation of the HC with the SC is critical to ensure the stabilisation of the pitch composite with in the new composite anode. A detailed examination of morphology, microstructure and electrochemical properties is reported here.