Growth of V ₂O ₅ nanorods from ball-milled powders and their performance in cathodes and anodes of lithium-ion batteries

The two-stage procedure of ball milling and annealing in air represents a prospective method of preparing nanorods of V ₂O ₅ with electrochemical properties suitable for the application in lithium-ion batteries. Commercially purchased V ₂O ₅ powder is milled in a ball mill as the first step of the synthesis. The as-milled precursor is subsequently annealed in air to produce the morphology of nanorods via solid-state recrystallization. We have recently investigated intermediate stages of the formation of nanorods, and this paper summarizes the synthesis method including the description of the current understanding of the growth mechanism. The obtained V ₂O ₅ nanorods have been assessed as an electrode material for both anodes and cathodes of lithium-ion batteries. When used in cathodes, the nanorods demonstrate a better retention of capacity upon cycling than that of the commercially available powder of V ₂O ₅. When used in anodes, the performances of nanorods and the reference V ₂O ₅ powder are similar to a large extent, which is related to a different operating mechanism of V ₂O ₅ in anodes. The experimentally observed capacity of V ₂O ₅ nanorods in an anode has stabilized at the level of about 450 mAh/g after few cycles.