Properties of Li_4Ti_5O_(12) synthesized by two-step calcination

Li2CO3 and TiO2 raw materials were pretreated by ultrasonic, then Li4Ti5O12 materials was prepared by two step calcination process. The effects of the synthesizing conditions on the crystalline structure, morphology and electrochemical properties were studied by XRD, SEM and cell charge/discharge performance test, and the best process was obtained. The results shows that the material synthesized at low calcined temperature of 600 ℃ shows a high crystallization and purity, the material synthesized at high calcined temperature of 800 ℃ shows a well-distributed structure. The best process for the preparation of Li4Ti5O12 is low calcined temperature of 600 ℃ for 8h sequentially high calcined temperature of 800 ℃ for 10 h, and the first discharge specific capacitance of the material at 0.1C is 170.6 mA-h/g, and after 20 cycles at 0.2C, the specific capacitance decreases from 152 mA-h/g to 150 mA-h/g with a retention rate of 98.7%.