Aqueous zinc-ion batteries (ZIBs) have emerged as promising candidates for large-scale energy storage systems. Vanadium-based cathodes stand out among cathode materials due to their high capacity, simple energy-storage mechanism, and good compatibility with high mass loading. 

However, the strong reactivity of water molecules in the electrolyte leads to severe vanadium dissolution at the cathode, hydrogen evolution, and zinc (Zn) corrosion at the anode, which hinders the long-lasting cycling performance of ZIBs, especially at low current density.

In a study published in Angewandte Chemie International Edition, a research team led by Prof. YANG Weishen and Prof. ZHU Kaiyue from the Dalian Institute of Chemical Physics of the Chinese Academy of Science constructed a robust hydrogen (H)-bond network within the electrolyte, which minimizes the reactivity of both H and oxygen (O) atoms in water, suppressing the deterioration on the bilateral electrode.

Researchers employed ethylene glycol as a cosolvent and sulfate ion (SO₄^2-) as structure-making anions to build the robust H-bond network. Ethylene glycol provided a dual-site H-bond anchoring effect on active water molecules for its abundant H-bond acceptors and donors, impeding the incursion of H and O atoms towards both electrodes. This dual-site anchoring was further strengthened by the ion-specific, structure-making capability of SO₄^2-, reducing vanadium dissolution at the cathode.

Moreover, ethylene glycol-induced modulation of Zn²⁺ solvation structures accelerated Zn²⁺ desolvation kinetics at the cathode and enhanced the (de)intercalation reversibility of both Zn²⁺ and H⁺. 

Benefitting from these synergistic effects, ZIBs using the ethylene glycol-containing electrolyte achieved long-lasting cycling stability, with 87% capacity retention after 500 cycles at 0.5 A g^-1. Besides, the optimized electrolyte enabled a 90 cm² pouch cell to deliver a high capacity of 2 Ah at 4 A, while maintaining 80% capacity retention after 70 cycles, highlighting the strong potential for practical scalability.