Dipole-dipole interactions for inhibiting solvent co-intercalation into a graphite anode to extend the horizon of electrolyte design

摘要

Developing advanced electrolytes is indispensable for next-generation lithium-ion batteries (LIBs). Yetthe strong solvating interaction between Li+ and various solvents often leads to sluggish desolvation andsolvent co-intercalation into graphite electrodes, thus limiting the scope of electrolyte design. Here, wepresent a mechanism of dipole–dipole interactions to facilitate desolvation and inhibit co-intercalationthrough deliberately tuning the interactions among Li+, solvents and non-coordinating molecules (nonsolvents).Specifically, the non-solvents counteract electrostatic attractions to tame the affinity between Li+and solvents without altering the primary solvation structure at medium Li salt concentration. Consequently, theweakened Li+-solvent strength enables facile desolvation and thus superior electrochemical compatibility withgraphite anodes for various solvents including DME (1,2-dimethoxyethane), DMSO (dimethyl sulfoxide), TMP(trimethyl phosphate), PC (propylene carbonate) and DEC (diethyl carbonate). We believe that the strategy ofdipole–dipole interactions can extend the horizon of electrolyte design towards achieving advanced LIBs.