Carbon coating of Li 4 Ti 5 O 12 -TiO 2 anode by using cetyl trimethyl ammonium bromide as dispersant and phenolic resin as carbon precursor

A new carbon coating method for improving the performance of anode material of lithium ion battery is proposed in this paper. In this method, cetyl trimethyl ammonium bromide (CTAB) is used as dispersant and phenolic resin formed in situ on Li 4 Ti 5 O 12 -TiO 2 is used as carbon precursor; thus, uniform coated sample with low carbon content is achieved. Three samples with different carbon contents are prepared, and their carbon content, morphology, structure, and electrochemical performance are investigated by thermogravimetry, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, electrochemical impedance spectroscopy, and charge-discharge test. It is found that the sample with a carbon content of as low as 2.5 wt.% exhibits superior electrochemical performance. It delivers an initial capacity of 162.4 mAh g −1 with capacity retention of 95 % after 200 cycles at 1 C rate. When cycled at a higher rate of 5 C, the sample delivers a capacity of 148 mAh g −1 with no apparent capacity decaying after 90 cycles. The superior performance of the developed anode can be attributed to the uniform carbon coating.