The charge/discharge mechanism and electrochemical performance of CuV2O6 as a new anode material for Li-ion batteries

Abstract

The charge/discharge mechanism of CuV₂O₆ as the anode for Li-ion batteries is studied for the first time, suggesting a phase transition in discharging, which initially involves the formation of LiV₂O₅ and Cu₃V₂O₈, the subsequent transition from Cu₃V₂O₈ to Li_xV₂O₅ and CuO, the insertion of lithium ions into LiV₂O₅, and later the reduction of CuO into Cu. The phase transition of Cu₃V₂O₈ is accompanied by an amorphization process, which is maintained in the subsequent discharging and charging processes. The CuV₂O₆/natural graphite electrode with a sodium alginate binder is prepared, which shows superior electrochemical performance. At a specific current of 110 mA g⁻¹, it delivers initial discharge and charge capacities of 725 and 453 mA h g⁻¹, respectively, maintaining 537 and 533 mA h g⁻¹ after 200 cycles.