Research progress on electrolyte key salts for sodium-ion batteries

Sodium-ion batteries (SIBs) are considered potential successors to lithium-ion batteries in the fields of energy storage and low-speed vehicles, thanks to their advantages such as abundant raw material sources, high energy density, and a wide operational temperature range. However, several scientific and engineering challenges still require attention in the development of sodium-ion batteries. Electrolyte salts, as a key component of sodium-ion battery electrolytes, play a critical role in battery performance. This paper provides a brief overview of the research progress on different electrolyte salt systems in sodium-ion batteries. It discusses characteristics such as ionic conductivity, electrochemical windows, electrochemical performance, and thermal safety in various solvent systems. Furthermore, the paper summarizes a series of strategies for controlling electrolyte and electrode interfaces, offering references for addressing the challenges in the mass production and application of sodium-ion batteries.