Abstract
Hard carbons are one of the most promising carbon anode materials for sodium ion batteries (SIBs) due to the high specific capacity and excellent cycle properties. Among the precursors used to synthesize hard carbon, natural starches are of great interest due to their unique morphologies. In this paper, ganyong starch based hard carbons (GSHC) were prepared by direct carbonization at various temperatures (700–1100) °C. The obtained hard carbons exhibit high reversible capacities of sodium-ion batteries of about 239 mAh g –1 at current density of 0.1 C. after 100 cycles. The excellent cycle profiles are attributed to the unique morphology and defect carbon structures.