Two-Stage Solvation of Lithium Polysulfides in Working Lithium–Sulfur Batteries

Lithium–sulfur (Li–S) batteries are promising in achieving high energy density but inferior in cycling lifespan since Li polysulfides (LiPSs) corrode Li metal anode. Weakening the electrolyte solvating power (ESP) for LiPSs effectively mitigates anodic corrosion but inevitably retards cathodic reaction kinetics. Herein, the correlation between the ESP and the LiPS redox kinetics in weakly solvating electrolyte is unveiled for achieving high-performance Li–S batteries. The ESP exhibits a two-stage variation tendency as the weakly solvating solvent (WSS) content increases, where the transition depends on whether the WSS enters the LiPS inner solvation shell. Once the WSS directly coordinates with LiPSs, the LiPS…

• NN
  National Natural Science Foundation of China

  Awards: 22393900, T2322015, 52394170, 22209010, 22109086, 22109007
• CP
  China Postdoctoral Science Foundation

  Award: GZB20240346
• TU
  Tsinghua University
• TI
  Tsinghua Initiative Scientific Research Program
• NK
  National Key Research and Development Program of China

  Award: 2021YFB2400300