Heteroatom-free cyclic ether enables synergistic optimization of solvation and hydrogen-bonding in aqueous zinc...

Aqueous zinc batteries (AZBs) offer inherent safety and cost advantages but still face severe Zn anode instability arising from dendrite growth and parasitic reactions. Conventional heteroatom-containing additives can alleviate these issues; however, they often raise environmental concerns and complicate interfacial chemistry. In this work, we introduce a heteroatom-free cyclic ether, 2-methoxy-1,3-dioxolane (MDOL), as a multifunctional electrolyte additive capable of simultaneously regulating Zn²⁺ solvation and reconstructing the hydrogen-bonding network. MDOL coordinates with Zn²⁺ to form loose solvation clusters, enhances de-solvation kinetics, and suppresses hydrogen evolution reaction and corrosion through favorable water-MDOL interactions. In addition, MDOL undergoes spontaneous in situ polymerization on the Zn surface, generating a robust organic interphase that promotes uniform Zn deposition. As a result, the MDOL-containing electrolyte enables Zn-Cu half cells to achieve an ultrahigh Coulombic efficiency of 99.85 % at 10 mA cm^-2 and 10 mAh cm^-2, along with an extended cycling life exceeding 3600 cycles at 5 mA cm^-2. Zn-NH₄V₄O₁₀ full cells (10 mg cm^-2 cathode, 10 μm Zn, 5 A g^-1) and 0.3 Ah Zn-NaV₃O₈ pouch cells (21 mg cm^-2 cathode, 100 μm Zn, 0.5 A g^-1) also demonstrate excellent long-term stability. This work provides a green molecular design strategy for developing sustainable and high-performance AZBs.