Sodium?ion batteries have become one of the research hotspots in the field of energy storage because of their advantages of low cost and high safety. This paper tried to clarify the development history of the hard carbon anode of sodium?ion batteries and address the current disadvantages of sodium?ion batteries, such as low initial coulombic efficiency, poor stability, and insufficient high magnification performance. In addition, to explore the sodium?ion storage mechanism in hard carbon, this paper used CiteSpace to visually analyze the development process of sodium?ion batteries and reviewed the research progress of performance optimization strategies for hard carbon anode in terms of material design, structure regulation, and function design and interface optimization. Furthermore, the paper summarized and discussed the existing hard carbon sodium storage mechanisms and finally prospected the development direction of the hard carbon anode of sodium?ion batteries.

Against the background of fossil fuel exhaustion and lithium resources shortage,sodium?ion batteries are considered promising secondary batteries due to their abundant resources,low theoretical cost, good quick?charge performance and excellent low?temperature performance.They are expected to play a key role in developing new energy,large?scale energy storage and low?speed electric vehicles.The selected cathode material is one of the important factors influencing the energy density,cycling performance and rate performance of a sodium?ion battery.This paper reviews the cathode materials of sodium?ion batteries,including transition metal oxides, polyanionic compounds,Prussian blue compounds and organic compounds.The paper introduced the advantages and disadvantages of sodium?ion batteries,analyzed the characteristics and research focuses of various cathode materials,and provided an outlook on the development direction of cathode materials for sodium?ion batteries.