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The amorphous cathode materials Li 2 O–V 2 O 5 –MoO 3 and Li 2 O–V 2 O 5 –MoO 3 –Fe 2 O 3 were produced via melt quenching. By analyzing the structure, elemental valence, and electrochemical characteristics of Li 2 O–V 2 O 5 –MoO 3 at different ratios, the effects of MoO 3 addition on vanadium-based amorphous cathode materials were explored. 20Li 2 O–60V 2 O 5 –20MoO 3 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 MoO 3 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 Li 2 O–V 2 O 5 –MoO 3 –Fe 2 O 3 is increased by adding Fe 2 O 3 to provide [FeO4], which strengthens the link between each structural unit. Vanadium oxidation reductions are promoted, and iron oxidation reductions replace the role of molybdenum in the charge/discharge. The discharge product transforms from LiVMoO 5 to Li 2 FeV 3 O 8 with increased de-embedding Li efficiency. The 20Li 2 O–60V 2 O 5 –10MoO 3 –10Fe 2 O 3 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 20Li 2 O–60V 2 O 5 –10MoO 3 –10Fe 2 O 3 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 MoO 3 and Fe 2 O 3 into vanadium-based amorphous to create a novel cathode material. This work offers a fresh perspective on investigating innovative lithium-ion battery cathode materials. [ABSTRACT FROM AUTHOR]

• Novel molybdenum-based cathode materials Li 2 O -MoO 3 -V 2 O 5 -P 2 O 5. • [MoO6], [PO4] and [VO4] co-form a stabilized amorphous structure. • Suppressing Mo5+/Mo4+ conversion improves cycling stability. Li 2 O-MoO 3 -P 2 O 5 and Li 2 O-MoO 3 -V 2 O 5 -P 2 O 5 amorphous cathode oxides were prepared using a simple melt quenching technique. The discharge-specific capacity of the 2Li 2 O-5MoO 3 -V 2 O 5 -2P 2 O 5 after 100 cycles was 141.43 mAh/g, with a capacity retention rate of 77.27 %, while the discharge-specific capacity of the 2Li 2 O-6MoO 3 -2P 2 O 5 after 100 cycles was 100.52 mAh/g, with a capacity retention rate of 55.78 %, in the voltage range of 1.5–4.2 V and at a current density of 10 mA/g. According to the findings, vanadium pentoxide may help molybdenum-based amorphous cathodes perform better electrochemically. In particular, the Mo5+/Mo4+ transition is inhibited, and the Mo6+/Mo5+ transition is promoted by the presence of the V5+/V4+ transition in the charge/discharge cycle of the Li 2 O-MoO 3 -V 2 O 5 -P 2 O 5 amorphous material, shortening the structural self-regulation process in the electrochemical cycle and significantly increasing cycle stability. The study provided a new idea for investigating novel cathode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

• Glass with a high vanadium content improved the migration efficiency of Li+. • Adding Fe 2 O 3 stabilized the structure and increased the contents of V3+ and V4+. • The cathode has the outstanding specific capacity and high-current response. Among new lithium-ion battery cathode materials, amorphous materials show unique advantages and vanadium-based materials are potential electrode materials. In our study, the vanadium-based Li 2 O-V 2 O 5 -B 2 O 3 glassy state electrode materials with high vanadium contents were prepared in air by the melt-quenching method. The structures and electrochemical performances of glass materials were investigated by various characterization methods. The Li 2 O-V 2 O 5 -B 2 O glass were mainly connected with VO 4 and BO 3 structural units to form a disordered network structure. The first discharge capacity of 20Li 2 O-60 V 2 O 5 -20B 2 O 3 glass cathode material reached 168.6 mAh/g at a current density of 100 mA/g. The conversion of V3+/V4+ and V4+/V5+ mainly occurred in the charge and discharge cycles. When 10% of B 2 O 3 was replaced by Fe 2 O 3 , the compactness and stability of the material were improved. Furthermore, with the addition of Fe 2 O 3 , the concentrations of low-valence V4+, V3+ and Fe2+ ions increased, thus contributing to the electrochemical performance. The specific capacity of 20Li 2 O-60V 2 O 5 -10B 2 O 3 -10Fe 2 O 3 cathode material increased significantly and the first discharge capacity was as high as 306.2 mA h/g at a current density of 100 mA/g. However, the specific capacity respectively decreased to 239 mA h/g in the second cycle and 120.3 mA h/g after 100 cycles. The study on vanadium-based glass cathode materials provided a new idea for the investigation of novel cathode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]