Synthesis and Electrochemical Properties of Lithium Titanate Anode Materials Powders by Solid State Reaction of Li and Spherical TiO<sub>2</sub> Powders

Abstract

Li4Ti5O12 powders were synthesized by solid state reaction of Li2CO3 and spherical composite powders of carbon and TiO2 (denoted as C/TiO2). C/TiO2 powders were synthesized by spray pyrolysis of using lactic acid aqueous solution. The particle characteristics of Li4Ti5O12 powders were determined by SEM, XRD and DTA-TG. DTA-TG showed that the carbon content was around 8 wt% in Li4Ti5O12 powders. XRD revealed that the spinel structure (Fd3m) was obtained by heating at 750 °C under N2 atmosphere. The first rechargeable capacity of Li4Ti5O12 anode was about 160 mAh/g at 1 C. That of Li4Ti5O12 anode decreased to 90 mAh/g at 20 C. The rechargeable capacity of Li4Ti5O12 anode decreased with increasing the rechargeable rate, but 81% of initial discharge capacity of Li4Ti5O12 anode was retained after 200 cycles at 1C