Structural design of anode materials for sodium-ion batteries

With the high consumption and increasing price of lithium resources, sodium ion batteries (SIBs) have been considered as attractive and promising potential alternatives to lithium ion batteries, owing to the abundance and low cost of sodium resources, and the similar electrochemical properties of sodium to lithium. Nevertheless, the lower energy density and limited cycling life of SIBs are still the main challenges impeding their wide application. Tremendous work has been done on anode materials for SIBs, and rational structural design is considered as an effective way to enhance their electrochemical performance. In this review, different types of anode materials for SIBs are summarized according to their reaction mechanism, and the problems for each type are pointed out. Specific structural design approaches for each type of anode material to improve its sodium storage performance are described in detail, and the benefits of different structural designs are explained as well.