Ni‐Regulated Partial Reconstruction of Hydrated Vanadium Oxide for Fast and Durable Aqueous Zinc‐Ion Batteries

Reconciling rapid Zn 2+ transport with structural durability remains challenging for layered vanadium‐oxide cathodes. In this work, a one‐step high‐temperature mixing hydrothermal strategy couples the glucose‐induced reductive reconstruction of V 2 O 5 with synchronous Ni 2+ incorporation, producing a Ni‐regulated H 2 V 3 O 8 ‐derived hydrated vanadium oxide (NiVOH) within 1 h at 240°C. Density functional theory screening of five guest cations identifies Ni 2+ as providing the lowest Zn 2+ migration barrier and enhanced electronic states near the Fermi level, consistent with comparative electrochemical measurements. Structural analyses reveal coexisting H 2 V 3 O 8 and Ni‐containing hydrated domains, accompanied by increased structural water and oxygen‐vacancy‐related defects. This domain‐balanced architecture preserves accessible hydrated galleries while restraining cycling‐induced deformation. NiVOH consequently delivers 433.4 mAh g −1 after 50 cycles at 0.1 A g −1 and sustains 282.6 mAh g −1 after 6000 cycles at 10 A g −1 . In situ x‐ray diffraction and real‐time fiber‐optic strain monitoring further reveal reversible lattice breathing and substantially reduced electrode‐level strain fluctuations. This work establishes rapid coupled reconstruction and guest‐ion regulation as an effective route for balancing ion accessibility and mechanical stability in layered aqueous battery cathodes.