High Lithium Storage Performance of Co Ion-Doped Li(4)Ti(5)O(12) Induced by Fast Charge Transport

In this study, Co(3)O(4)-doped Li(4)Ti(5)O(12) (LTO) composite was designed and synthesized by the hydrothermal reduction method and metal doping modification method. The microstructure and electrochemical performance of the Co(3)O(4)-doped Li(4)Ti(5)O(12) composite were characterized by XRD, SEM, TEM, electrochemical impedance spectroscopy, and galvanostatic tests. The results showed that Li(4)Ti(5)O(12) particles attached to lamellar Co(3)O(4) constituted a heterostructure and Co ion doped into Li(4)Ti(5)O(12) lattice. This Co ion-doped microstructure improved the charge transportability of Li(4)Ti(5)O(12) and inhibited the gas evolution behavior of Li(4)Ti(5)O(12), which enhanced the lithium storage performance. After 20 cycles, the discharge specific capacity reached stability, and the capacity retention maintained 99% after 1,000 cycles at 0.1 A/g (compared to the capacity at the 20th cycle). It had an excellent rate performance and long cycle stability, in which the capacity reached 174.6 mA h/g, 2.2 times higher than that of Li(4)Ti(5)O(12) at 5 A/g.