Boosting Performance of PANI@N-WHL-AC by a Modified Water-in-Salt-Electrolyte Strategy for Zinc-Ion Batteries

Aqueous zinc-ion batteries (ZIBs) show promise for safe, affordable energy storage, but their performance is often constrained by the need for improved cathode design and electrolyte optimization to enable effective ion transport at interfaces. Here, a sustainable water hyacinth leaf-derived N-doped activated carbon/polyaniline composite (PANI@N-WHL-AC) is developed as a cathode for ZIBs and tested in an 8 m Zn(ClO₄)₂ electrolyte, regulated with methanesulfonic acid. The optimized electrolyte enhances reaction kinetics, reduces parasitic reactions, and stabilizes Zn²⁺ plating/stripping. As a result, the Zn||PANI@N-WHL-AC cell achieves a high specific capacity of approximately 105.6 mAh g^-1 at 1.0 A g^-1, an energy density of about 101.5 Wh kg^-1, and a power density near 692.8 W kg^-1, with approximately 80% capacity retention over 2500 cycles. This work highlights electrolyte-managed dual-ion kinetics as a valuable approach to unlocking the full potential of conducting polymer/biomass-derived carbon composite cathodes in advanced aqueous ZIBs.