Formation of LiF‐rich Cathode‐Electrolyte Interphase by Electrolyte Reduction

Abstract The capacity of transition metal oxide cathode for Li‐ion batteries can be further enhanced by increasing the charging potential. However, these high voltage cathodes suffer from fast capacity decay because the large volume change of cathode breaks the active materials and cathode‐electrolyte interphase (CEI), resulting in electrolyte penetration into broken active materials and continuous side reactions between cathode and electrolytes. Herein, a robust LiF‐rich CEI was formed by potentiostatic reduction of fluorinated electrolyte at a low potential of 1.7 V. By taking LiCoO 2 as a model cathode, we demonstrate that the LiF‐rich CEI maintains the structural integrity and suppresses electrolyte…

• TU
  Tianjin University