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The research on rechargeable aqueous Zinc(Zn)‐ion batteries has expanded exponentially. However, the performance of Zn anodes during cycling and their commercial application is restricted by severe corrosion and dendritic formation. In this study, a facile approach is presented to address these challenges by introducing minute quantities of Zr(NO3)4 into the 3 m ZnSO4 electrolyte. The Zr(NO3)4 additive facilitates the creation of a protective layer comprising spatial gradient oxidation alloy (GOA) particles. The insulating zirconium‐based materials provide the necessary potential gradient to induce the Zn plate under the covering film. As a proof of concept, the in situ GOA coating anode exhibits exceptional cycling stability for 8000 cycles and an ultralow hysteresis voltage of 41 mV at current density of 5 mA cm−2. Furthermore, Density Functional Theory analyses reveal that the GOA coating anode homogenizes the electric field surrounding the Zn anode surface providing abundant zincophilic sites for Zn nucleation compared to bare Zn plates. This ensures uniform Zn deposition, preventing dendritic growth. In addition, the in situ characterization and computation of Gibbs free energy (ΔGH*) reveal that the GOA coating anode may effectively suppress the hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

In aqueous/nonaqueous metal‐sulfur batteries, sulfur‐based redox couple exhibits significant challenges mainly due to its low electrochemical kinetics, potential shuttle effect, and large volume change. Although massive researches have been conducted to optimize or replace metal anode and cathode composite, major challenges caused by the dependency on sulfur‐based redox couple still remain. In this study, a novel redox couple of CuS/Cu2S, which provides the same theoretical capacity (based on conventional S/S2− redox couple) by changing the valence of ion charge carrier, is proposed. For achieving high reversibility, commercially viable laser‐induced graphene (LIG) is fabricated and used for the first time in aqueous metal‐sulfur batteries. By virtue of the synergism between novel redox couple and LIG, aqueous CuS/Cu2S battery delivers a highly reversible capacity of 1654.9 mAh g−1 in the initial cycle and retains 91.2% with 1509.5 mAh g−1 after 328 cycles. When being cycled at 2.8 A g−1, its reversible capacity still retains 92.1% after 410 cycles. This study provides a new choice by using a sulfur‐free redox couple from screening thermodynamic parameters and analyzes the functional mechanism of LIG by density functional theory, aiming to innovate the energy storage mechanism of aqueous metal‐sulfur batteries. [ABSTRACT FROM AUTHOR]