Boosting Electrochemical Performance of Ti ₂ Nb ₁₀ O ₂₉ Anodes via Cl ⁻ Doping for High‐Power Lithium‐Ion Batteries

With the growing global demand for energy, lithium‐ion batteries (LIBs) have gained significant attention as efficient energy storage systems. Among various anode materials, Ti 2 Nb 10 O 29 (TNO) offers promising electrochemical properties but suffers from limited rate capability and cycling stability. In this work, a series of Cl − ‐doped TNO samples (Cl x % ‐TNO, x = 4, 8, 12, 16, 20) are synthesized using a one‐step solid‐phase method. Cl − doping promotes the uniform growth and dispersion of primary TNO particles, expands the unit cell volume and interplanar spacing, and creates wider channels for lithium‐ion transport. Due to its higher electronegativity, Cl − optimizes charge distribution, improves electronic conductivity, and induces oxygen vacancies, providing more active reaction sites. The conductivity of Cl 12% ‐TNO reaches 1.67 × 10 −7 S cm −1 , which is two orders of magnitude higher than that of undoped TNO. Galvanostatic intermittent titration technique (GITT) tests reveal that Cl 12% ‐TNO maintains a higher lithium‐ion diffusion coefficient throughout cycling. Electrochemical evaluation shows that Cl 12% ‐TNO delivers an initial charge‐specific capacity of 303.4 mAh g −1 , retain 182.49 mAh g −1 at 30 C, and maintains 146.64 mAh g −1 after 300 cycles at 10 C, with a retention rate of 82.91%. This study demonstrates the effectiveness of Cl − doping in enhancing TNO performance for LIB applications.