Zn0.52V2O5−a⋅1.8 H2O Cathode Stabilized by In Situ Phase Transformation for Aqueous Zinc‐Ion Batteries with Ultra‐Long Cyclability

作者：Wenhao Liang, Dewei Rao, Tao Chen, Rongfeng Tang, Jun Li, Huile Jin · 发表于：Angewandte Chemie International Edition · 年份：2022 · DOI：10.1002/anie.202207779 · 被引用次数：130 · 研究领域：Advanced battery technologies research、Supercapacitor Materials and Fabrication、Perovskite Materials and Applications

Abstract Developing cathode materials integrating good rate performance and sufficient cycle life is the key to commercialization of aqueous zinc‐ion batteries. The hyperstable Zn0.52V2O5−a⋅1.8 H2O (ZVOH) cathode with excellent rate performance has been successfully developed via an in situ self‐transformation from zinc‐rich Zn3V3O8 (ZVO) in this study. Different from the common synthetic method of additional Zn2+ pre‐insertion, ZVOH is obtained from the insertion of structural H2O and the removal of excess Zn2+ in ZVO, ensuring the lattice structure of ZVOH remains relatively intact during the phase transition and rendering good structural stabilities. The ZVOH delivers a reversible capacity of 286.2 mAh g−1 at 0.2 A g−1 and of 161.5 mAh g−1 at 20 A g−1 over 18 000 cycles with a retention of 95.4 %, demonstrating excellent rate performance and cyclic stability. We also provide new insights on the structural self‐optimization of Znx(CF3SO3)y(OH)2x−y⋅n H2O byproducts and the effect on the mobility of Zn2+ by theoretical calculations and experimental evidence.