Niobate Li+‐storage anode materials with shear ReO3 crystal structures have attracted intensive attention due to their inherent safety and large capacities. However, they generally suffer from limited rate performance, cyclic stability, and temperature adaptability, which are rooted in their insufficient interlayer spacings. Here, sodium niobate (NaNb13O33) micron‐sized particles are developed as a new anode material owning the largest interlayer spacing among the known shear ReO3‐type niobates. The large interlayer spacing of NaNb13O33 enables very fast Li+ diffusivity, remarkably contributing to its superior rate performance with a 2500 to 125 mA g−1 capacity percentage of 63.2%. Moreover, its large interlayer spacing increases the volume‐accommodation capability during lithiation, allowing small unit‐cell‐volume variations (maximum 6.02%), which leads to its outstanding cyclic stability with 87.9% capacity retention after as long as 5000 cycles at 2500 mA g−1. Its cyclic stability is the best in the research field of niobate micron‐sized particles, and comparable to that of “zero‐strain” Li4Ti5O12. At a low temperature of −10 °C, it also exhibits high rate performance with a 1250 to 125 mA g−1 capacity percentage of 65.6%, and even better cyclic stability with 105.4% capacity retention after 5000 cycles at 1250 mA g−1. These comprehensively good electrochemical results pave the way for the practical application of NaNb13O33 in high‐performance Li+ storage.

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Niobates are very promising anode materials for Li+-storage rooted in their good safety and high capacities. However, the exploration of niobate anode materials is still insufficient. In this work, we explore ~1 wt% carbon-coated CuNb13O33 microparticles (C-CuNb13O33) with a stable shear ReO3 structure as a new anode material to store Li+. C-CuNb13O33 delivers a safe operation potential (~1.54 V), high reversible capacity of 244 mAh g–1, and high initial-cycle Coulombic efficiency of 90.4% at 0.1C. Its fast Li+ transport is systematically confirmed through galvanostatic intermittent titration technique and cyclic voltammetry, which reveal an ultra-high average Li+ diffusion coefficient (~5 × 10–11 cm2 s−1), significantly contributing to its excellent rate capability with capacity retention of 69.4%/59.9% at 10C/20C relative to 0.5C. An in-situ XRD test is performed to analyze crystal-structural evolutions of C-CuNb13O33 during lithiation/delithiation, demonstrating its intercalation-type Li+-storage mechanism with small unit-cell-volume variations, which results in its capacity retention of 86.2%/92.3% at 10C/20C after 3000 cycles. These comprehensively good electrochemical properties indicate that C-CuNb13O33 is a practical anode material for high-performance energy-storage applications.

A general modification for the solid-state reaction preparation of energy-storage materials is explored through using sintering aids with redox activity.