The safety aspect of sodium ion batteries for practical applications

Sodium-ion batteries (SIBs) with advantages of abundant resource and low cost have emerged as promising candidates for the next-generation energy storage systems. However, safety issues existing in electrolytes, anodes, and cathodes bring about frequent accidents regarding battery fires and explosions and impede the development of high-performance SIBs. Therefore, safety analysis and high-safety battery design have become prerequisites for the development of advanced energy storage systems. The reported reviews that only focus on a specific issue are difficult to provide overall guidance for building high-safety SIBs. To overcome the limitation, this review summarizes the recent research progress from the perspective of key components of SIBs for the first time and evaluates the characteristics of various improvement strategies. By orderly analyzing the root causes of safety problems associated with different components in SIBs (including electrolytes, anodes, and cathodes), corresponding improvement strategies for each component were discussed systematically. In addition, some noteworthy points and perspectives including the chain reaction between security issues and the selection of improvement strategies tailored to different needs have also been proposed. In brief, this review is designed to deepen our understanding of the SIBs safety issues and provide guidance and assistance for designing high-safety SIBs.