Surface‐Fluorinated Conductive Carbon for Coupled Electron/Ion Transport Through the Graphite Anode

ABSTRACT

Graphite (Gr) is the dominant anode material for commercial lithium‐ion batteries (LIBs). However, its fast‐charging capability is often constrained by sluggish Li ⁺ transport and large interfacial polarization under high current densities. Conventional conductive carbons mainly serve as electronic percolation networks and do not contribute to Li ⁺ transport regulation. Here, we report a gas‐phase fluorination strategy that converts commercial nanosized conductive carbon into a surface‐fluorinated conductive carbon (F‐SP) to enable coupled electron/Li ⁺ transport and localized LiF‐rich interphase regulation in Gr anodes. The introduced semi‐ionic and polar C‐F species enhance electrolyte wettability and Li ⁺ affinity while maintaining the conductive carbon framework. Partial electrochemical defluorination of F‐SP further promotes the in situ formation of a nanoscale LiF‐rich interphase on the surface during cycling, regulating local interfacial chemistry and improving charge‐transfer kinetics. Benefiting from this synergistic transport and interphase regulation, the F‐SP‐based Gr anode exhibits improved rate capability and cycling stability with reduced polarization and accelerated Li ⁺ transport kinetics. The NCM523||Gr/F‐SP full‐cell delivers a reversible capacity of 95.2 mAh g ⁻¹ at 10C and retains 81.99% of its capacity after 500 cycles at 1C. This work demonstrates that rational surface fluorination can upgrade conventional conductive carbon into multifunctional kinetic regulators for fast‐charging Gr anodes.