Study of the Electrochemical Properties of Li4Ti5O12 Doped with Ba and Sr Anodes for Lithium-Ion Secondary Batteries

The spinel material Li4Ti5O12 has attracted considerable attention as an anode electrode material for many battery applications owing to its light weight and high energy density. However, the real capacity of Li4Ti5O12 powder as determined by the solid-state method is lower than the ideal capacity. In this study, we investigated the effect of the dopants in M-doped spinel BaxLi4.2xTi5O12 (x=0.005, 0.05, 0.1) powders prepared by the solid-state reaction method and used as the anode material in lithiumion batteries. The results confirmed the effect of the Ba and Sr dopants on the powder properties of the spinel Li4Ti5O12, which exhibited a pure spinel structure without any secondary phase in its XRD pattern. Moreover, the electrochemical properties of the spinel M-LTO materials were investigated using a half cell. The electrochemical data show that cells with anodes made of undoped Li4Ti5O12 and Ba- and Sr-doped Li4Ti5O12 have discharge capacities of 97, 130, and 112 mAh/g, respectively, at the first cycle. Moreover, the Ba- and Sr-doped spinel Li4Ti5O12 demonstrated good properties in the mid-voltage range at 1.55 V, showing stable cyclic voltammogram properties which surpassed those of the same material without Ba or Sr at 1 C after 100 cycles.