Research Trend on Conversion Reaction Anodes for Sodium-ion Batteries

Development of low cost rechargeable batteries has been considered as a significant task for future large-scale energy storage units (i.e. electric vehicles, smart grids). Sodium-ion batteries (SIBs) have been recognized as a promising alternative to replace conventional lithium-ion batteries (LIBs) because of their abundancy and economic benign. Nevertheless, Na ions have larger ionic radius than that of Li ions, resulting in sluggish transport of Na ions in electrodes for cell operation. There have been efforts to seek suitable anode materials for the past years operated based on three different kinds of reaction mechanism (intercalation, alloy reaction, and conversion reaction). In this review, we introduce a class of conversion reaction anode materials for Na-ion batteries, which have been reported.