Solvation Structure Tuning Induces LiF/Li₃ N-Rich CEI and SEI Interfaces for Superior Li/CF_x Batteries

The electrode/electrolyte interfaces play an important role in the electrochemical reaction kinetics to alleviate the severe polarization and voltage hysteresis in lithium primary batteries. Herein, C₅ F₅ N is proposed as an electrolyte additive to tune the characteristics of the electrode/electrolyte interfaces. The Li/CF_x primary battery with C₅ F₅ N additive exhibits an excellent discharge-specific capacity of 981.4 mAh g^-1 (0.1 C), a remarkable high-rate capability of 598 mAh g^-1 (15 C), and an outstanding energy/power density of 1068.7 Wh kg^-1 /24362.5 W kg^-1 . It also shows remarkable storage performance with 717.2 mAh g^-1 at 0.1 C after storage at 55 °C for 2 months. The excellent performance of the Li/CF_x batteries is closely related to the improved and stable Li₃ N/LiF-rich homogeneous interfaces induced by the C₅ F₅ N additive, which results in uniform distribution of Li⁺ flux, facilitated electrochemical kinetics, and increased rate capability of Li/CF_x battery. Therefore, C₅ F₅ N is expected to be a promising electrolyte additive, and the related electrode/electrolyte interface engineering provides an effective and facile strategy to increase the performance of the lithium primary battery.