Preparation and electrochemical properties of Li₄Ti₅O₁₂ as an electrode material

Li₄Ti₅O₁₂(M₁) was obtained by solid reaction process with LiNO₃ and TiO₂ as reactants. XRD analysis indicates that the main phase of the produced powder is Li₄Ti₅O₁₂ compound oxide with spinel structure. The initial discharge capacity of M₁ at 35 mA·g^-1 reaches 170 mAh·g^-1, which is comparable to the theoretical capacity, and the first coulombic efficiency is 92%. M₁ performs well when it charges and discharges with high current density, and the discharge capacities reach 151, 140 and 115 mAh·g^-1 at 175, 350 and 875 mA·g^-1, respectively. The discharge capacities of M₁, comparing with that of ME prepared by conventional solid-state sintering of LiOH and TiO₂, increase by 5%, 10% and 26% at 175, 350 and 875 mA·g^-1, respectively. Cyclic voltammogram suggests that the electrode of M₁ has low polarization, good reversibility and high electrochemical activity. The charge transfer resistances of M₁ measured through AC impedance are 16 and 2012 after lithium insertion and extraction, respectively.