Enhanced Performance of Lithium-Ion Batteries with Lithium Bis(fluorosulfonyl)imide and Lithium Hexafluorophosphate Binary-Salt Electrolytes

Lithium bis(fluorosulfonyl)imide (LiFSI) based lithium-ion batteries (LIBs) are known for their superior electrochemical performance; however, they are hindered by the severe corrosion of aluminum current collectors. This study extensively explores the effects of a Lithium bis(fluorosulfonyl)imide and lithium hexafluorophosphate (LiFSI-LiPF ₆ ) binary-salt electrolyte on both the electrochemical performance and the aluminum corrosion in LIBs. These electrolytes increase in ionic conductivity as the LiFSI concentration rises. Graphite/LNCM cells using LiFSI show reduced resistance, enhanced rate performance, and greater cycling stability. A LIB featuring the LiFSI-LiPF ₆ (0.4 M LiFSI + 0.7 M LiPF6) binary-salt electrolyte achieves 86.8% capacity retention after 1800 cycles. Furthermore, no aluminum corrosion was detected after extensive high-temperature stability tests. Consequently, this electrolyte configuration offers a promising approach to improve the longevity and storage capabilities of LIBs.