A High-Performance Aqueous Zinc-Thiocyanogen-Iodine Battery with High Capacity and Dual Platforms

Aqueous zinc-iodine batteries (AZIBs) have emerged as promising energy storage devices owing to their advantages of low cost, inherent safety and environmental friendliness. However, most AZIBs primarily operate through a single I0/I- redox reaction, which results in constrained operating voltage and capacity. Recently, the four-electron conversion mechanism of I⁺/I⁰/I^- has been activated to solve these issues, yet this process encounters challenges such as intricate cross side reactions. Herein, high-capacity and dual-platform Zn-(SCN)₂-I₂ batteries (ZSIBs) have been prepared by introducing a water-insalt (WIS) electrolyte system with I- and SCN- . The introduction of V2CTx MXene effectively inhibited the side-reaction and shuttle effects present in ZSIBs, demonstrated a discharge specific capacity of 806.4 Ah cm^-2 (290 mAh g-1), the device can retain 97.84% in 500 charge/discharge cycles. Additionally, the combination of oxygen-enriched carbon(ACC) and V2CTx MXene enabling a high discharge specific capacity of 2995.8 Ah cm-2 and energy density of 3.60 mWh cm-2, thereby shedding new light on the design and development of aqueous Zn-ion batteries.