Research Progress on Electrolyte Additives for Sodium Ion Batteries

In view of the gradual depletion of lithium resources, sodium-ion batteries (SIBs) have emerged as a viable alternative to lithium-ion batteries (LIBs). This is primarily attributed to their comparable operational principles and abundant reserves of sodium resources. As an essential component of the secondary battery, the electrolyte is of paramount importance in the functioning of SIBs, and the electrode-electrolyte interface constructed by it affects the battery performance. Adding electrolyte additives in LIBs is a low-cost and efficient method that can enhance the performance of the electrolyte and the interface between the electrode and electrolyte. This method is also applicable to SIBs. Therefore, in this study, we provide a comprehensive overview of various electrolyte additives, including but not limited to carbonate additives, sulfur-containing additives, silicon-containing additives, phosphorus-containing additives and inorganic additives. We extensively analyze the impact of these additives on the electrode-electrolyte interface and the electrochemical performance of SIBs. The purpose of this review is to comprehensively evaluate the current status of electrolyte additives in SIBs, which serves as both a basic overview of the existing situation and a practical guide for selecting suitable additives for practical applications of SIBs.