Synthesis of Lithium Titanium Oxide (Li₄Ti<i>₅</i>O₁₂) through Sol-Gel Method and the Effect of Graphene Addition in Lithium-Ion Battery Anodes

Abstract

Li4Ti5O12 (lithium titanium oxide) or LTO is extensively utilized as active material in Li-ion battery anode mainly due to its zero strain properties and excellent lithium-ion intercalation/deintercalation reversibility with negligible volumetric change. However, LTO is still faced with low electronic conductivity problem, thus the addition of another material such as graphene is necessary to overcome. In this study, LTO was synthesized using sol-gel method with addition of Li varied from 35, 40 and 55 wt% which was controlled by addition of Li2CO3. XRD analysis was performed to investigate the crystal structure and phase characteristic of synthesized powder. The results revealed that LTO with addition of 55 wt% Li exhibited the highest purity of Li4Ti5O12 phase of 97.7%. It was then added with 5 wt% of graphene. Two-coin cells of Li-ion batteries were made from LTO powders without and with graphene addition as active materials for anode and their electrochemical performances were analyzed. LTO without and with graphene show conductivity of 3.40710-5 and 2.48810-5 S/cm, while obtained specific capacity was about 140 mAH and 85 mAh, respectively. This would require further optimization for current experimental condition particularly on graphene addition.