Solvothermal Guided V₂O₅ Microspherical Nanoparticles Constructing High-Performance Aqueous Zinc-Ion Batteries

Rechargeable aqueous zinc-ion batteries have attracted a lot of attention owing to their cost effectiveness and plentiful resources, but less research has been conducted on the aspect of high volumetric energy density, which is crucial to the space available for the batteries in practical applications. In this work, highly crystalline V₂O₅ microspheres were self-assembled from one-dimensional V₂O₅ nanorod structures by a template-free solvothermal method, which were used as cathode materials for zinc-ion batteries with high performance, enabling fast ion transport, outstanding cycle stability and excellent rate capability, as well as a significant increase in tap density. Specifically, the V₂O₅ microspheres achieve a reversible specific capacity of 414.7 mAh g^-1 at 0.1 A g^-1, and show a long-term cycling stability retaining 76.5% after 3000 cycles at 2 A g^-1. This work provides an efficient route for the synthesis of three-dimensional materials with stable structures, excellent electrochemical performance and high tap density.