Sole‐Solvent High‐Entropy Electrolyte Realizes Wide‐Temperature and High‐Voltage Practical Anode‐Free Sodium Pouch Cells

Abstract Anode‐free sodium batteries (AFSBs) hold great promise for high‐density energy storage. However, high‐voltage AFSBs, especially those can stably cycle at a wide temperature range are challenging due to the poor electrolyte compatibility toward both the cathode and anode. Herein, high‐voltage AFSBs with cycling ability in a wide temperature range (−20–60 °C) are realized for the first time via a sole‐solvent high‐entropy electrolyte based on the diethylene glycol dibutyl ether solvent (D2) and NaPF 6 salt. The sole‐solvent high‐entropy electrolyte with unique solvent‐ions effect of strong anion interaction and weak cation solvation enables entropy‐driven electrolyte salt disassociation and…

• NN
  National Natural Science Foundation of China

  Awards: 52302287, 52172178, 12374284
• NS
  Natural Science Foundation of Beijing Municipality

  Award: 2222059