Possibility of carbon coating with Li4Ti5O12 at low temperature for high rate of lithium ion batteries

Li4Ti5O12/carbon (LTO/C) nanoparticles were synthesised by solution combustion method, and malic acid were used as carbon sources. The mixture of LTO pristine and carbon source was calcination sintered at low temperature (350 degrees C). This temperature was relatively low temperature in comparison with previous sintering temperature (500-700 degrees C). The physical characteristics of LTO/C nanoparticles were investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and inductively coupled plasma spectroscopy. Their electrochemical performance was evaluated by electrochemical impedance spectroscopy, cyclic voltammograms, constant current charge-discharge and rate charge-discharge. As the results of the measurement, LTO/C-0.8 had discharge specific capacity of 71.1 mAh g(-1) at high rate of 40C. The cycle performance of LTO/C-0.8 was excellent as 168.5 mAh g(-1) (at similar to 160 mA g(-1)) and 104.5 mAh g(-1) (at similar to 3200 mA g(-1)) after 50 cycles, and it keeps 98.9 and 96.0% of capacity at the second cycle.