Hydrated Layered Vanadium Oxide as a Highly Reversible Cathode for Rechargeable Aqueous Zinc Batteries

• Published in: Advanced functional materials 2019-03, Vol.29 (10), p.n/a
• Main Authors: Zhang, Ning, Jia, Ming, Dong, Yang, Wang, Yuanyuan, Xu, Jianzhong, Liu, Yongchang, Jiao, Lifang, Cheng, Fangyi
• Format: Article
• Language: English
• Subjects: aqueous zinc batteries; cathode; Cathodes; Electrode materials; Energy storage; flexible devices; Flux density; hydrated vanadium oxide; Lithium; Materials science; Photoelectrons; Rechargeable batteries; Storage batteries; Storage systems; Substrates; Transmission electron microscopy; Vanadium oxides; X-ray diffraction; Zinc
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.201807331

Rechargeable aqueous zinc batteries have gained considerable attention for large‐scale energy storage systems because of their low cost and high safety, but they suffer from limitations in cycling stability and energy density with advanced cathode materials. Here, a high‐performance V5O12·6H2O (VOH) nanobelt cathode uniformly located on a stainless‐steel substrate via a facile electrodeposition technique is reported. We show that the hydrated layered VOH cathode enables highly reversible and ultrafast Zn2+ cation (de)intercalation processes, as confirmed by various electrochemical, X‐ray diffraction, X‐ray photoelectron spectroscopy, and transmission electron microscopy analyses. It is demonstrated that the binder‐free VOH cathode can deliver a discharge capacity of 354.8 mAh g−1 at 0.5 A g−1 with a high initial Coulombic efficiency of 99.5%, a high energy density of 194 Wh kg−1 at 2100 W kg−1, and a long cycle life with a capacity retention of 94% over 1000 cycles. In addition, a flexible quasi‐solid‐state Zn–VOH battery is constructed, achieving a reversible capacity of ≈300 mAh g−1 with a capacity retention of 96% after 50 cycles and displaying excellent electrochemical behaviors under different bending states. This work sheds light on the development of rechargeable aqueous zinc batteries for stationary grid storage applications or flexible energy storage devices. V5O12·6H2O nanobelts self‐supported on a stainless‐steel substrate are prepared by electrodeposition and applied as a binder‐free cathode for rechargeable aqueous zinc batteries. The V5O12·6H2O cathode with a large layered structure (≈1.18 nm) enables highly reversible Zn2+ (de)intercalation, and displays a high energy density (194 Wh kg‐1 at 2100 W kg‐1) and a long cycling life (94% retention after 1000 cycles).