High Lithium Storage Performance of Co Ion-Doped Li4Ti5O12 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.