Unlocking Long Life Aqueous Zinc‐Sulfur Rechargeable Battery Derived from Zinc Waste Powering 30 LEDs

Abstract Aqueous Zinc‐sulfur (Zn‐S) rechargeable batteries are emerging as promising next‐generation energy storage devices due to safety, capacity, cost and efficiency. However, Zn corrosion, polarization, low conductivity and volume expansion of sulfur cathode are the bottlenecks for battery stability and capacity. Herein, we report a dual strategy involving sulfanilamide (SA) as additive to stabilize Zn, paired with hollow Ni x Fe y O 4 to confine sulfur, mitigating volume expansion and enhancing conductivity along with iodine as redox mediator to improve the Zn 2+ kinetics. The designed battery demonstrated an excellent specific capacity of 1260 mAh g −1 at 0.1 C with 81% capacity retention after 1000 cycles at 1 C. The SA mitigates the hydrogen evolution reaction (HER) by 3.5 times and 2.8‐fold reduction in corrosion rate of Zn anode, which is, supported by Raman, and 1 H NMR spectroscopy and furthercomplimented by computational studies. The symmetric Zn||Zn cell with SA was stable for more than 770 h, demonstrating an ultra‐high stability of Zn anode. Formation of ZnS was monitered by electrochemical in‐situ Raman spectroscopy. The designed Zn‐S homemade pouch cell powered a panel of 30 red LED for 93 h and furthered powered fan, demonstrating exceptional sustainability.