Electrochemical properties of nano-sized Li4Ti5O12 powders synthesized by a sol-gel process and characterized by X-ray absorption spectroscopy

• Published in: Journal of power sources Vol. 146; no. 1-2; pp. 204 - 208
• Main Authors: VENKATESWARLU, M, CHEN, C. H, DO, J. S, LIN, C. W, CHOU, T. C, HWANG, B. J
• Format: Conference Proceeding Journal Article
• Language: English
• Published: Lausanne Elsevier Sequoia 26.08.2005
• Subjects: Applied sciences; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology; Lithium battery; Electrochemical properties; X ray absorption spectrometry; Sol gel process; Nano-sized; Secondary cell; XAS; XRD; Lithium Titanium Oxides; Performance; Cycle performance; Li4Ti5O12
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2005.03.016

Nano-sized spinet Li4Ti5O12 powders were synthesized by a sol-gel process. The cubic spinel structure without impurity phase of the synthesized Li4Ti5O12 powders was confirmed by X-ray diffraction. The average grain size of the synthesized powders was found to be around 39 nm. In situ X-ray absorption spectroscopy (XAS) has been performed on the Li4Ti5O12 electrode to investigate its change in the oxidation state and the local environment of the electrode during charging and discharging processes. The X-ray absorption near edge spectroscopy (XANES) analysis showed that the absorption edge energy shifts towards lower and higher energy, respectively, during discharge and charge ; processes, indicating the reversibility of the electrode is quite good. It was worthy to note that the discharging capacity and the charging capacity obtained for the nano-sized Li4Ti5O12 electrode in the potential range of 0.01-1.75 V are 255 and 242 mAh g, respectively. However, the specific charge capacity obtained in the potential range of 1.0-2.0 V is 126 mAh g-1. The spinel Li4Ti5012 electrode maintains the cubic spinet structure for repeated cycling resulting in good cyclability and the capacity retention.