Charge-Discharge Mechanisms of Ammonium Vanadium Bronze NH4V4O10 Nanobelts as Cathode for Lithium-ion Battery

Ammonium vanadium bronze NH₄V₄O₁₀ nanobelts show potential interesting properties for an application as the cathode in lithium-ion batteries with an original discharge capacity of 171.8 mAh/g. Charge-discharge mechanisms of the material was investigated by using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) analysis. Results show that the discharge process passes through three different steps of lithium ion intercalation into the material, whereas the charge process can be completed via two steps of lithium ion de- intercalation out the material. And that the causes of discharge/charge capacity attenuation can be ascribed to the increase of the charge transfer resistance, and further resulted in decrease in cycle life of the cell.