Abstract
Niobates are promising all-climate Li(+)-storage anode material due to their fast charge transport, large specific capacities, and resistance to electrolyte reaction. However, their moderate unit-cell-volume expansion (generally 5%-10%) during Li(+) storage causes unsatisfactory long-term cyclability. Here, "zero-strain" NiNb(2)O(6) fibers are explored as a new anode material with comprehensively good electrochemical properties. During Li(+) storage, the expansion of electrochemical inactive NiO(6) octahedra almost fully offsets the shrinkage of active NbO(6) octahedra through reversible O movement. Such superior volume-accommodation capability of the NiO(6) layers guarantees the "zero-strain" behavior of NiNb(2)O(6) in a broad temperature range (0.53%//0.51%//0.74% at 25// - 10//60 °C), leading to the excellent cyclability of the NiNb(2)O(6) fibers (92.8%//99.2% // 91.1% capacity retention after 1000//2000//1000 cycles at 10C and 25// - 10//60 °C). This NiNb(2)O(6) material further exhibits a large reversible capacity (300//184//318 mAh g(-1) at 0.1C and 25// - 10//60 °C) and outstanding rate performance (10 to 0.5C capacity percentage of 64.3%//50.0%//65.4% at 25// - 10//60 °C). Therefore, the NiNb(2)O(6) fibers are especially suitable for large-capacity, fast-charging, long-life, and all-climate lithium-ion batteries.