Enhanced electrochemical performance of core-shell Li4Ti5O12/PTh as advanced anode for rechargeable lithium-ion batteries

A nanocomposite of Li4Ti5O12 particles coated with polythiophene (PTh) was fabricated as advanced anode for rechargeable lithium-ion batteries. The conducting PTh layer was successfully coated on the surface of Li4Ti5O12 through the in-situ oxidative polymerization method. Benefiting from the core-shell structure, specific capacities as high as 171.5, 168.2 and 151.1 mA h g−1 at 0.2, 1 and 10 C are obtained in the Li4Ti5O12/PTh composite. The electrochemical results also show that the Li4Ti5O12/PTh exhibits remarkably improved cycling performance as compared with the Li4Ti5O12 anode. Moreover, the charge-transfer resistance of Li4Ti5O12/PTh electrode is much lower than that of the bare Li4Ti5O12, revealing that the PTh coating can significantly increase the electron conductivity between the Li4Ti5O12 particles. The excellent electrochemical performance of the as-fabricated Li4Ti5O12/PTh composite can be ascribed to the PTh layer which can suppress the dissolution of active material into the LiPF6 electrolyte and enhance the electron conductivity of Li4Ti5O12 nanocrystals. Thus, the Li4Ti5O12/PTh composite is an advanced anode for use in high performance lithium-ion batteries application.