Hydrated hybrid vanadium oxide nanowires as the superior cathode for aqueous Zn battery

Zinc batteries are at the forefront of aqueous energy storage due to their intrinsic safety and low cost. Various vanadium oxides stand out among the few cathode candidates. Herein, we demonstrate a new heterogeneous vanadium oxide nanowire with V₂O₅·nH₂O shell and V₃O₇·H₂O core, named h-VOW, as a promising cathode candidate for Zn batteries. Thanks to the synergies of multivalent states of vanadium elements associated with inherent high conductivity, in an aqueous electrolyte, h-VOW/Zn battery delivers high discharge capacity (455 mAh g⁻¹ at 0.1 A g⁻¹), energy density (340 Wh kg⁻¹) and power density (9105 W kg⁻¹). Moreover, the gel electrolyte imparts satisfied deformability and weather resistance to the flexible quasi-solid-state battery, allowing it to withstand extremely harsh conditions without catastrophic failure.