Anomalous Zn2+ Storage Behavior in Dual‐Ion‐In‐Sequence Reconstructed Vanadium Oxides

Abstract

AbstractVanadium oxides with fast and stable Zn2+ storage are of great significance to the development of high‐performance aqueous zinc ion batteries (ZIBs), and yet they commonly suffer from structural instability and sluggish diffusion kinetics. Herein, a new “dual‐ion‐in‐sequence” intercalation strategy based on quenching is proposed to address these issues. Interestingly, it is found that the Zn2+ storage mechanism evolves from the common solid‐state ion diffusion kinetic into an intercalation pseudocapacitance as a result of the enlarged interlayer spacing of V2O5. Together with the expanded interlayer spacing arising from the “dual‐ion‐in‐sequence” intercalation, oxygen defects are simultaneously generated at the sub‐surface of the reconstructed Li@MnVO materials. Benefitting from the improved ionic diffusivity, intercalation pseudocapacitance, and fast charge transferability, full cell based on Li@MnVO cathode shows impressive rate capability and excellent cycling stability of 5000 cycles with a high energy density of 253 Wh kg‐1 at 10 A g‐1. More importantly, the capacity can maintain at 125 mAh g‐1 at 4 A g‐1 even under a raised mass loading of 10 mg cm‐2. The proposed “dual‐ion‐in‐sequence” intercalation strategy of manipulating V2O5 structure at atomic scales is a viable pathway for the high‐performance layered metal oxides, not only for ZIBs but also for other energy storage systems.