A temperature-dependent solvating electrolyte for wide-temperature and fast-charging lithium metal batteries

High safety and stable wide-temperature operation are essential for lithium metal batteries (LMBs). Herein, we designed an amide-based eutectic electrolyte composed of N-methyl-2,2,2-trifluoroacetamide (NMTFA) and lithium difluoro(oxalato)borate, enabling LMBs’ wide-operating temperature range and fast-charging performance. In addition to high thermal tolerance and non-flammability, our designed electrolyte (AEEs-5) triggers a temperature-dependent Li solvation structure due to the thermal motion of polar NMTFA, ensuring appropriate Li-ion de-solvation kinetics at 25°C–100°C. Moreover, the AEEs-5-induced solid electrolyte interphase (SEI) with high inorganic contents and thermal stability greatly reduces the…

• NN
  National Natural Science Foundation of China

  Awards: 52102282, 22379093
• SJ
  Shanghai Jiao Tong University
• CA
  China Academy of Space Technology

  Award: 2020QNRC001
• NU
  National University's Basic Research Foundation of China
• FR
  Fundamental Research Funds for the Central Universities

  Awards: 22X010201631, 23X010301599