Hydrogen peroxide promotes zinc deposition nucleation and boosts the reversibility of aqueous rechargeable zinc-ion batteries.

This article focuses on the use of hydrogen peroxide (H₂O₂) as an electrolyte additive to inhibit zinc dendrite growth in rechargeable aqueous zinc-ion batteries (ZIBs), thereby enhancing their cycle life and stability. The addition of H₂O₂ modifies the coordination environment of hydrated zinc ions, lowers the nucleation over-potential, and promotes uniform zinc deposition, which suppresses the irregular and sharp dendritic growth responsible for short circuits. Experimental results demonstrate that incorporating approximately 3% H₂O₂ into a 1 M ZnSO₄ electrolyte extends the battery cycle life from 80 hours to over 1,000 hours and improves Coulombic efficiency to about 98%, with dendrites forming as smooth, layered structures rather than irregular protrusions. This approach offers a cost-effective, eco-friendly strategy to regulate zinc deposition behavior and improve the performance of zinc-ion batteries without compromising electrolyte stability.