Eco-friendly anodic exfoliation of graphite via a dual-salt electrolyte for high-loading and fast-charging lithium-ion battery anodes

Sustainable mass production of high-quality graphene is essential for its use as a conductive additive in high-power energy storage systems, as conventional synthesis often causes structural damage and environmental toxicity. Here, we report an eco-friendly anodic electrochemical exfoliation strategy using a dual-salt aqueous electrolyte of NaCl and NaClO 4 . This synergistic approach exploits the small hydrated radius of chloride ions (Cl − ) for initial channel opening and the strong expansion effect of perchlorate ions (ClO 4 − ) for rapid delamination, preserving the carbon lattice integrity. By optimizing the NaCl/NaClO 4 molar ratio, we balanced defect density and carbon purity to maximize battery performance. The optimized process yielded high-quality few-layer graphene with carbon content exceeding 94 at%, low defect density (I D /I G = 0.13), and high powder electrical conductivity (1237.9 S/cm). Used as a two-dimensional (2D) conductive additive in thick, high-loading graphite anodes (∼4.5 mg/cm 2 ) at a reduced content of 0.55 wt%, the graphene enabled 82.7% capacity retention at an ultrahigh rate of 15C and 99.6% retention after 100 cycles at 0.5C via a robust 2D conductive network. These results confirm that the crystalline 2D network facilitates Li-ion transport and mechanical stability, highlighting the potential of this green route for next-generation high-power lithium-ion batteries.