One-step synthesis of Cl-doped Li₄Ti₅O₁₂ during electrode fabrication process with improved specific capacity

One-step synthesis of Cl-doped Li₄Ti₅O₁₂ has been achieved by solution method at a low temperature (40 °C) during the electrode fabrication process of Li-ion batteries. The Cl-doped Li₄Ti₅O₁₂ has a higher specific capacity than the pristine Li₄Ti₅O₁₂. According to the SEM and XRD results, the doping of Cl does not destroy the intrinsic structure of Li₄Ti₅O₁₂. The specific capacity of Cl-doped Li₄Ti₅O₁₂ at 0.2 C, 0.5 C, 1 C, and 2 C rates in the range of 1–3 V is 179.0, 160.2, 149.4, and 132.3 mAh g⁻¹, respectively. Compared with the pristine Li₄Ti₅O₁₂ material, the specific capacities are increased by 16.2%, 13.5%, 18.1%, and 16.7%, respectively. The CV results show that the Cl-doped Li₄Ti₅O₁₂ material has a higher lithium ion transport rate compared with the pristine Li₄Ti₅O₁₂. EIS measurements show that Cl doping can effectively decrease charge transfer impedance and facilitate Li⁺ ion diffusion. Overall, the Cl-doped Li₄Ti₅O₁₂ anode material prepared by a solution method has higher ionic conductivity and better electrochemical performance compared with the pristine Li₄Ti₅O₁₂ anode material.