Preparation of V<sub>2</sub>O<sub>5</sub> Composite Cathode Material Based on In Situ Intercalated Polyaniline and Its High-Performance Aqueous Zinc-Ion Battery Applications.

Abstract

With the rapid growth of renewable energy, the need for efficient and stable energy storage systems has become increasingly urgent. Aqueous zinc-ion batteries (AZIBs) can offer high safety, abundant zinc supply, and promising electrochemical properties. However, their performance is limited by poor electronic conductivity, slow Zn²⁺ diffusion, and structural degradation of conventional cathode materials. To address these issues, an in situ polyaniline (PANI) intercalation strategy for vanadium oxide cathodes is introduced in this paper. The conductive PANI chains play three key roles: (1) expand and stabilize interlayer spacing, (2) enhance electronic conductivity, and (3) provide mechanical support to prevent structural collapse and zinc-dendrite formation. A flower-like PANI-V₂O₅ hybrid is synthesized via synchronous oxidative polymerization, forming a hierarchical architecture without inert intercalants. The resulting electrode achieves a high specific capacity of 450 mAh·g^-1 at 0.1 A·g^-1 and retains 96.7% of its capacity after 300 cycles at 1 A·g^-1, with excellent rate performance. These findings demonstrate that PANI intercalation enhances ion transport, electronic conductivity, and structural integrity, offering a promising design approach for next-generation AZIBs cathodes.