Tuning solvation structure to enhance low temperature kinetics of lithium-ion batteries

The performance degradation at low temperatures limits the application of lithium-ion batteries (LIBs) in frigid regions and extreme weather conditions. The slow charge transfer kinetics including the Li+ desolvation and the Li+ migration in the electrode/electrolyte interface (EEI) film, have been precisely identified as the main rate-limitation of LIBs at low temperatures. In this review, different from the conventional EEI regulation, we provide a systematic survey of electrolyte engineering to improve the low-temperature performance from the perspective of tuning the Li+ solvation structure. From atomic insight, we summarize the effects of concentration, coordination environment, solvent molecular structure, and size effect on the Li+ desolvation process and the electrode/electrolyte interface at low temperatures. And the corresponding strategies for solvation structure regulation which follows the integrated principles of weakening the Li+-solvent interaction, inducing more anions participate in the solvation shell and forming anions-derived inorganic-rich EEI, are also discussed with the goal of facile Li+ desolvation and favorable EEI. Finally, the relationships among the solvation structure, the desolvation process, interphasial properties and the low-temperature performance are established, and the future challenges are put forward, offering perspectives on electrolyte designs for low-temperature LIBs.