Atomic Insights into Advances and Issues in Low-Temperature Electrolytes

The design of low-temperature electrolytes is a key technology to improve the low-temperature performance of electrochemical energy storage devices and expand their application fields. However, the current design strategies for low-temperature electrolytes remain in the optimization of formula, without systematic and in-depth consideration of the internal relationship between the fundamental interactions and performances of electrolytes at low temperature. Here, starting from the four fundamental interactions among cations, anions, and solvents in the electrolyte, this review for the first time analyzes the temperature-dependent mechanisms of their interactions and corresponding physicochemical properties of electrolytes from atomic insights. Then, the research progress in low-temperature electrolytes is summarized according to the relationships of these interactions. The possible new development directions in the future are also pointed out. This review provides a theoretical reference for the design of low-temperature electrolytes.