An elaborate insight of lithiation behavior of V2O5 anode

Vanadium pentoxide (V2O5) has been a promising insert-type cathode material and/or a potential high energy anode material for rechargeable lithium ion batteries (LIBs). However, the lithiation behavior of V2O5 anode has been a long-standing challenge. In this study, we design nanoflake-assembled three-dimensional hollow porous V2O5 microspheres via a one-step template-free solvothermal-based method to enhance its structural stability as well as electrochemical activity. Commendably, this original product evaluated as anode electrodes for LIBs exhibits outstanding cycling stability and rate capability. It delivers a high reversible capacity of 527 mAh g-1 after 100 cycles at 0.1 A g-1, and a stable capacity of 318 mAh g-1 at 3.0 A g-1 in the potential range of 0.01 V and 3.0 V (vs. Li/Li+). Furthermore, electrode kinetics and performance evolution was studied by use of electrochemical impedance spectroscopy (EIS). Following these efforts, a definite and tenable lithiation mechanism of V2O5 anode is presented based on redox behaviors, X-ray powder diffraction (XRD) results, and other convincing proofs, providing valuable revelation for the understanding of conversion reaction and reaction mechanism toward other vanadium oxide anode materials in lithium/sodium ions storage. Meanwhile, the research perspective and strategy presented herein can be extended to other active materials in LIBs and/or sodium ion batteries.