Electrochemical and transport properties of Te-doped Li4Ti5O12 as anode material for lithium-ion half/full batteries

Te-doped Li4Ti5O12 (LTO) was prepared by a ball milling-assisted solid-state method in air. The as-prepared powders were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and electrochemical impedance spectroscopy. Li4Ti4.95Te0.05O12 powder sintered at 850 °C presented improved ionic and electronic conductivities of 2.20×10-7 S·cm-1 and 2.40×10-9 S·cm-1 at room temperature, respectively, an order of magnitude higher than those of intrinsic LTO. Electrochemical analysis showed that the discharge specific capacities of Li4Ti4.95Te0.05O12 in Li half cells at 1 C and 5 C were 162.49 mAh·g-1 and 143.5 mAh·g-1, respectively, with capacity retention rates of 98.8% and 98.2% after 100 cycles. The Li4Ti4.95Te0.05O12/LiNi0.5Mn0.3Co0.2O2 full cells also showed a good specific capacity of 101.8 mAh·g-1 at 1 C and delivered good temperature adaptability. This study provides an effective strategy for the preparation of high-performance LTO anodes for lithium-ion batteries.