Synthesis, characterisation and electrochemical evaluation of lithium titanate anode for lithium ion cells

Abstract

Lithium titanate, Li4Ti5O12 (LTO), a promising anode material for high power lithium ion (Li-ion) cells, was synthesised by sol-gel method using hydrated titania and lithium carbonate as precursors. The synthesised material was characterised by Fourier-transform infrared spectroscopy and X-ray diffraction methods. The morphology of the material was studied by scanning electron microscopy. The electrochemical evaluation of LTO electrode in Li-ion cells was carried out by assembling LTO electrode versus Li metal as counter electrode in half cell. The cell was subjected to initial charge-discharge cycles at C/10 rate and then tested at different rates viz. C/5, C/2, 1C, 2C, 5C, 10C and 20C. The specific capacity at these rates was 170, 167, 165, 164, 161, 160, 160 and 155 mAh/g, respectively. The columbic efficiency of the cell was close to 100% at these rates. Herein, we demonstrate that a pristine LTO formed by simple sol-gel method can retain more than 90% of the capacity at high current rate of 20C.