Plasma-Induced CoF Formation and Carbon Coating for Bond Adjustment and Polarization Inhibition in High-Rate Li/CF Batteries.

Fluorinated carbon (CF) contains strong covalent C-F bonds, leading to severe electrochemical polarization in Li/CF batteries with a limited rate performance. Herein, a synergy technology was developed to prepare a CF/CoF/C composite for a high-rate Li/CF battery combining bond adjustment and polarization inhibition effects. Typically, the CF/CoF/C composite in situ generated coupling with a mixed-liquid phase reaction and CH/Ar plasma-inducing technology. In detail, the intermediate/CF mixtures were prepared by mixing Co(NO) as a cobalt source and NaOH as a precipitant, immediately following the CH/Ar plasma treatment. The introduction of CoF favors the CH decomposition into the carbon layer deposition during the plasma bombardment. Furthermore, the as-designed composite possesses rich semi-ionic C-F bonds, which suppress the polarization of CF. The charge transfer resistance of the CF/CoF/C composite is reduced from 267.9 to 51.7 Ω compared with raw CF. The energy density of the CF/CoF/C cathode increased to 1.89 times with a value as high as 1185.65 Wh/kg at 15 C. This novel cathode combines energetic CoF and a conductive carbon layer to modify CF by plasma-inducing technology, synergistically achieving CF bond adjustment and polarization inhibition to address high-rate batteries.