Journal of Power Sources, Vol.202, 374-379, 2012
Low-temperature synthesis of nano-micron Li4Ti5O12 by an aqueous mixing technique and its excellent electrochemical performance
We demonstrate an aqueous mixing technique to synthesize nano-micron Li4Ti5O12 by spray drying followed by solid-state calcination. The as-prepared materials are characterized by XRD, TG-DTA, SEM, TEM and electrochemical measurements. Well-crystallized Li4Ti5O12 with no impurity can be obtained at a relatively low calcined temperature (650 degrees C) owing to the effect of nanoscale and uniform particles. Because of the rough and porous nano-micron spherical particles, the obtained Li4Ti5O12 shows excellent rate capability and cycle ability. The initial discharge capacities are 174.8,170.5, 167.5, 165.3, 158.2, 152.1, 130.9 and 111.9 mAh g(-1) at the 0.1, 0.5, 1, 2. 5, 10, 15 and 20 C rates, respectively. After 100 cycles, the as-prepared Li4Ti5O12 retains 99.6%. 96.9%, 98.8%, 89.3%, 90.4% and 89.0% of its initial discharge capacities at the 1, 2, 5, 10, 15 and 20 C rates, respectively. (C) 2011 Elsevier B.V. All rights reserved.