Li2O-V2O5-MoO3-Fe2O3 amorphous cathode material for lithium-ion batteries based on coordinated multi-electron effect and stable network structure

The amorphous cathode materials Li2O-V2O5-MoO3 and Li2O-V2O5-MoO3-Fe2O3 were produced via melt quenching. By analyzing the structure, elemental valence, and electrochemical characteristics of Li2O-V2O5-MoO3 at different ratios, the effects of MoO3 addition on vanadium-based amorphous cathode ma-terials were explored. 20Li2O-60V2O5-20MoO3 has a high initial capacity (268.0 mAh/g for the first reversible discharge at a current density of 50 mA/g), which is based on the properties that MoO3 supplies additional oxidation reductions and has [MoO6] structural units to widen the diffusion channels for lithium ions in the network structure. Unfortunately, the network of the structural elements [MoO6] and [VO4] is unstable, which causes the material to have poor cycle stability and exhibit an unsatisfactory current response. The network structure stability of Li2O-V2O5-MoO3-Fe2O3 is increased by adding Fe2O3 to provide [FeO4], which strengthens the link between each structural unit. Vanadium oxidation reductions are promoted, and iron oxidation re-ductions replace the role of molybdenum in the charge/discharge. The discharge product transforms from LiVMoO5 to Li2FeV3O8 with increased de-embedding Li efficiency. The 20Li2O-60V2O5-10MoO3-10Fe2O3 achieves an initial reversible specific capacity of 255.2 mAh/g at 50 mA/g, 139.7 mAh/g additional specific capacity after 100 cycles, and 110.5 mAh/g specific capacity at a high current density of 400 mA/g. The test findings show that 20Li2O-60V2O5-10MoO3-10Fe2O3 efficiently increases high-current responsiveness and cycle stability while retaining a high capacity. In this study, we propose a compositional design strategy, which is based on the coordinated multi-electronic effect of multiple transition metal elements and the design of a stable disordered network structure, to incorporate MoO3 and Fe2O3 into vanadium-based amorphous to create a novel cathode material. This work offers a fresh perspective on investigating innovative lithium-ion battery cathode materials.