High Specific Capacity Amorphous Vanadium-Nickel Composite Lithium-Ion Battery Anode.

Amorphous V2O5-TeO2-based glass materials are good candidates for next-generation lithium-ion battery anodes. In this work, excessive loss of specific capacity in the first cycle and a low capacity retention rate have been addressed by introducing NiO/NiSe into the V2O5-TeO2 glass system. V5+ decreased in content from 84.4% to 37.7% and 33.7%, while V4+ and V3+ elevated from 15.6% to 56.5% and 60.0%, as well as from 0% to 5.8% and 6.3%, respectively. Thus, the initial specific capacity increased from 699.8 to 1048.5 mAh/g and the electrochemical impedance decreased from 648 to 242 Ω. The conductivity increased by 12.5%. Density functional theory simulations show no state density at the Fermi level before and after lithium adsorption, indicating that the system is a semiconductor with a transition barrier of 0.667 eV. This work helps to provide a new strategy for the ordered and disordered transformation and lithium storage properties.