Niobium–Tungsten Oxides for Ultralow‐Temperature Lithium‐Ion Batteries Operation at −60 °C

Abstract Lithium‐ion batteries (LIBs) experience a notable drop in capacity and cycling stability in extremely cold environments. This decline is largely due to the low intercalation potential and the sluggish kinetics of the graphite anode. Here, micron‐sized niobium–tungsten oxide with a crystallographic shear structure is proposed as a next‐generation anode material for low‐temperature rechargeable batteries, and its lithium storage mechanism at sub‐zero temperatures is investigated. It is demonstrated that niobium–tungsten oxide exhibits the free‐path low‐hindrance migration with diffusion energy barrier of 0.284 and 0.291 eV, as well as 3D diffusion channels. This structural advantage of niobium–tungsten oxide possesses high reversibility and superior lithium‐ion diffusion coefficients at low temperatures, revealed by in situ X‐ray diffraction at −40 °C and in situ Raman spectroscopy combined with simulation calculations. Remarkably, niobium–tungsten oxide remains rechargeable at −70 °C. The full cell based on niobium–tungsten oxide anode and LiCoO 2 cathode retains 64.5% of its room temperature capacity and a high cycling capacity retention of 97.9% after 70 cycles at −60 °C. This work provides a new avenue toward the design of high‐performance anodes and rechargeable LIBs energy storage devices at ultra‐low temperatures.