Dual Pre-Insertion Strategy to Achieve High-Performance Vanadium Oxide toward Advanced Cylindrical Zinc Ion Batteries

The low electrical conductivity of vanadium-based oxides and their structural instability have been major challenges as cathodes for zinc ion batteries (ZIBs). Pre-insertion strategies are one means of effectively improving the structural stability of cathode materials. Furthermore, it is important to develop a safe and simple method to produce vanadium-based cathode material in large quantities for commercialized ZIBs. Thus, this work prepared a Zn2+ and H2O intercalated V2O5 (ZnVO·1.2H2O) as cathode by one-step stirring. Zn2+ and H2O intercalation expanded the layer spacing and promoted the diffusion kinetics of the ZnVO·1.2H2O electrode material. As a result, ZnVO·1.2H2O nanowire electrode materials exhibit a higher specific capacity and cycle performance. Even at a current density of 4 A g–1, almost 100% of the initial capacity is still retained after 3000 cycles. In addition, benefiting from this large-scale preparation technology, this work applied the electrode materials to cylindrical ZIBs. The 21 700 cylindrical ZIB with a high mass load can reach a maximum discharge capacity of 75.03 mAh at a current of 0.4 A. This work not only provides an experimental basis for the preparation of high-capacity, homogeneous electrode materials but also provides a potential reference for the development of cylindrical ZIBs.