Improved high-rate performance of Li4Ti5O12/carbon nanotube nanocomposite anode for lithium-ion batteries

• CNT modification reduces resistance and polarization of Li4Ti5O12.
• CNT modification results in fast lithium insertion/extraction kinetics.
• Li4Ti5O12–CNTs (4 wt.%) exhibit a good fast charge–discharge performance.

Li4Ti5O12 nanosheet and Li4Ti5O12 nanosheet/CNT nanocomposite were prepared in ethyl alcohol medium by a low-cost hydrothermal method. The CNTs are incorporated into the Li4Ti5O12 nanosheet homogenously, and then provide a highly conductive network for electron transportation. Li4Ti5O12 nanosheet/CNT composite with 4 wt.% CNTs exhibits excellent rate capability and superior cycle life between 1 and 2.5 V. Li4Ti5O12 nanosheet/CNTs (4 wt.%) shows superior rate performance with discharge capacities of 137.5 mAh g− 1 at 2 C charge–discharge rate after 90 cycles and 128.3 mAh g− 1 at 3 C charge–discharge rate after 120 cycles. The significantly improved rate capability of the Li4Ti5O12 nanosheet/CNT electrodes can be mainly ascribed to the reduced resistance and polarization and improved lithium diffusion coefficient. The same strategy adopted in this work could be helpful to develop advanced electrochemical energy storage systems with long cycle life and high rate performance.