Ultra-Stable Aqueous Zinc Anodes: Enabling High-Performance Zinc-Ion Batteries via a ZnSiF₆-Derived Protective...

Zinc-ion batteries (ZIBs) hold immense promise as next-generation energy storage solutions, however, the practical application of zinc anodes is hindered by dendrite formation and parasitic side reactions. Engineering a stable solid- eletrolyte interphase (SEI) is crucial for addressing these issues. This study proposes a novel strategy to enhance Zn anode performance by incorporating a ZnSiF₆ additive into a standard ZnSO₄ (ZSO) electrolyte. The ZnSiF₆ additive facilitates the formation of a stable, fluorine-rich SEI on the Zn anode surface. Characterization reveals a hierarchical SEI structure, primarily composed of porous alkali zinc sulfate (ZHS) with embedded ZnF₂. This unique architecture promotes rapid zinc ion desolvation and efficient transport, enhances corrosion resistance, and mitigates hydrogen evolution. Consequently, ZnSiF₆-modified cells exhibit exceptional cycling stability, exceeding 3000 hours at 0.5 mA cm^-2 and 560 hours at 10 mA cm^-2, significantly outperforming ZSO-based cells. The modified cells also achieve high areal capacities (10 mAh cm^-2), indicating superior zinc utilization. This work provides key insights for designing stable electrode/electrolyte interfaces, contributing to the development of high-performance aqueous ZIBs.