Niobium-Manganese Composite Oxides as Anode Materials for Lithium-Ion Batteries: Electrochemical Performance

Manganese-based oxides are regarded as highly promising anode materials for lithium-ion batteries due to their high theoretical specific capacity, abundant resources, and environmental friendliness. This study aims to enhance the structural stability of manganese-based anodes during cycling by introducing structurally stable niobium oxide doping into manganese oxides. Using manganese dioxide (MnO₂) and niobium pentoxide (Nb₂O₅) as raw materials, three sets of manganese-niobium composite oxide precursors with different molar ratios (namely Mn/Nb-10, Mn/Nb-20 and Mn/Nb-30) were prepared via high-energy ball milling and subsequently heat-treated at a uniform calcination temperature. Electrochemical testing revealed that among the three samples, the Mn/Nb-10 exhibited the most outstanding electrochemical performance: its reversible specific capacity remained at 1113.81 mAh·g^-1 after 300 cycles, and it maintained a discharge specific capacity of 337.04 mAh·g^-1 at the high current density of 1 A·g^-1 after 500 cycles. More significantly, the incorporation of niobium markedly suppressed volume expansion during lithium-ion deintercalation, effectively mitigating electrode structural pulverization and capacity decay. This nanocomposite exhibits high reversible specific capacity, good rate capability, and stable cycling performance. It holds broad application prospects in high-energy-density lithium-ion battery systems and is expected to become an ideal candidate for next-generation high-performance anode materials.