Research progress of carbon anode materials for sodium-ion batteries

Abstract

Due to the merits of abundant resources and low cost, sodium-ion batteries (SIBs) have attracted extensive attention in the field of large-scale energy storage. The deployment of SIBs is limited by electrode materials with high specific capacity and long cycling stability. Carbon materials are promising anode candidates for SIBs due to the advantages of high controllability and excellent stability. Up to now, the researches on carbon materials mainly involve graphite, amorphous carbon, heteroatom-doped carbon and biomass-derived carbon. However, the problems with carbon materials, including thermodynamic instability of sodium-graphite compounds, large volume expansion and low initial Coulombic efficiency, remain and restrict the development of SIBs. Modification on the carbon structure and interfacial optimization of carbon anodes and electrolytes has been demonstrated as effective strategies to promote the electrochemical performances. Herein, we summarize the structural characteristics, electrochemical performances, storage mechanisms, problems, and improvement methods of carbon materials, and provide insights into the researches of carbon anode materials for SIBs.