Freeze-drying synthesis of metal element (Zr, Cr, Co)–doped Li₄Ti₅O₁₂ anode material for enhanced electrochemical energy storage in lithium-ion batteries

Lithium titanate (Li₄Ti₅O₁₂, LTO) anode materials doped with Zr, Cr, and Co were prepared by a simple solution freeze-drying (SFD) strategy. Doping with Zr, Cr, and Co metal ions can reduce the charge transfer resistance and enhance the diffusion rate and conductivity of lithium ions. Among the prepared samples, LTO-0.1Zr shows the best electrochemical performance with the reversible capacities of 286.8, 258.5, 235.4, 196.2, 151.5, and 119.6 mAh g⁻¹ at 0.5, 1, 2, 5, 10, and 20 C, respectively. After 500 cycles at 10 C, a high retention rate of 94.6% for LTO-0.1Zr capacity can still be achieved. As a result, this study provides a simple and effective way to improve the electrochemical performance of LTO as anode material for high rate lithium-ion batteries.