Crystallographic Engineering Enables Fast Low-Temperature Ion Transport of TiNb2O7 for Cold-Region Lithium-Ion Batteries

• Sb element is introduced into TiNb2O7 successfully, enabling crystallographic engineering that narrows the bandgap and broadens Li+ transport channels. • The TNO-Sb/Nb electrode exhibits superior low-temperature performance, delivering a high reversible capacity of 140.4 mAh g−1 at 20 C and maintaining 102.6 mAh g−1 at −30 °C. • The synergy of Sb/Nb doping enhances structural stability, as confirmed by synchrotron X-ray 3D nano-CT and in situ XRD, mitigating volume expansion during cycling. • This work provides a strategic design for fast-charging, cold-region lithium-ion batteries, achieving 89.8% capacity retention after 700 cycles at 10 C.