Electrolyte solvation structure as a stabilization mechanism for electrodes

Rechargeable batteries with high capacity, power and safety are urgently required for current and future technological demands. The solid electrolyte interphase (SEI) layer has a dominant impact on battery cyclability and the solvate is the key factor that determines the SEI layer. In this perspective, we first review the recent advances in understanding the influences of electrolyte composition on the solvation chemistry and SEI layer. The solvation structure of electrolytes seems to be the root cause of the stability of electrodes during cell cycling. We then discuss the strategy to manipulate the solvation chemistry by adjusting the compositions of the electrolytes, including the solvent, salt, concentration and additive. Finally, we concisely discuss the challenges in characterizing the structure of the solvates at the electrode|electrolyte interface. This review refreshes our current understanding of the key factors for stable electrode|electrolyte interfaces in the pursuit of high-performance battery systems.