Anion–Diluent Pairing for Stable High-Energy Li Metal Batteries

Rechargeable Li metal batteries (LMBs) have attracted wide attention as promising candidates for the next generation of energy-storage systems. However, limited Coulombic efficiency and unregulated dendrite growth restrict its application. Here, we report a kind of electrolyte by introducing fluorinated aromatic diluents into high-concentration electrolytes (HCEs). Unlike other localized HCEs, the fluorinated aromatic diluents pairing with anions promote the formation of a homogeneous and robust solid–electrolyte interphase (SEI), which endows Li metal with an ultrahigh Coulombic efficiency of ∼99.8%. The Li||LiNi0.8Co0.1Mn0.1O2 battery holds a capacity retention of >80% over 260 cycles even with a thin Li…

• NN
  National Natural Science Foundation of China

  Awards: 22161142017, 22072134
• NS
  Natural Science Foundation of Zhejiang Province

  Award: LZ21B030002