Urea-mediated construction of hollow flower-like nitrogen-doped Nb2O5 microspheres for fast-charging lithium-ion batteries

Developing advanced anode materials that are highly safe and fast-charging is particularly important for next-generation lithium-ion batteries. Nb 2 O 5 stands out as a promising high-power anode contender owing to its high working potential and pronounced intercalation pseudocapacitance behavior. Nevertheless, the practical implementation has been fundamentally constrained by poor intrinsic conductivity and sluggish Li-ion diffusion kinetics. In this paper, we present the first successful synthesis of hollow flower-like N-doped Nb 2 O 5 microspheres via a template-free hydrothermal approach, using urea as both a morphology regulator and nitrogen source. The unique hierarchical hollow structure not only facilitates rapid electron/ion transport but also relieves volume change during charge/discharge. In addition, nitrogen doping effectively enhances electronic conductivity and lowers the Li + diffusion barrier. Benefiting from the integrated merits of nitrogen doping and the unique flower-like structure, the prepared hollow flower-like N-doped Nb 2 O 5 delivers exceptional rate performance (150 mAh g −1 at 20C) and outstanding cycling endurance (80.0 % retention after 2000 cycles). When paired with an LiNi 0.5 Co 0.3 Mn 0.2 O 2 cathode, the full cell achieves a high capacity of 107 mAh g −1 under 10C and maintains 72.6 % capacity retention after 500 cycles. This work opens a new avenue for engineering high-rate electrode materials, demonstrating great potential for fast-charging energy storage applications. A 3D hollow flower-like N-doped Nb 2 O 5 microspheres were first synthesized using urea as the morphology regulator and nitrogen source. The high rate capability and satisfactory cycle lifespan are received, positioning N-Nb 2 O 5 as a highly prospective anode material for high-power LIBs. • Hollow flower-like N-Nb 2 O 5 microspheres are successfully prepared by template-free hydrothermal approach. • The urea as the morphology regulator and nitrogen source. • The Hollow flower-like N-Nb 2 O 5 electrode exhibits outstanding rate and cyclic performances. • NCM532||N-Nb 2 O 5 full cell displays excellent electrochemical performances.