Spinel Li4Ti5−xZrxO12 (0 ⩽ x ⩽ 0.25) materials as high-performance anode materials for lithium-ion batteries

Spinel Li4Ti5−xZrxO12 (0 ⩽ x ⩽ 0.25) materials were prepared by a solid-state reaction method using Li2CO3, ZrO2 and TiO2 as raw material, and the structure and electrochemical performance of the material were investigated by TG–DTA, XRD, SEM, CV, EIS and charge–discharge tests. The Zr-doped Li4Ti5O12 materials show much improved rate capability and specific capacity compared with pristine Li4Ti5O12. Especially, the pristine Li4Ti5O12 offers about 111 mA h g−1, but Li4Ti4.9Zr0.1O12 delivers a remarkable capacity of 172 mA h g−1 at 2 C charge–discharge rate. Li4Ti4.9Zr0.1O12 sample delivers a capacity of 155 mA h g−1 even after 150 cycles at 5 C charge–discharge rates, implying the possibility for high power applications, such as HEV and PHEV. The rate capability of the anode material made from the modified powder is significantly improved when discharged at high current rates due to the reduced charge transfer resistance and fast lithium insertion/extraction kinetics.

► The reduced charge transfer resistance improves the rate capacity of Zr-doped Li4Ti5O12.
► Zr doping results in a fast lithium insertion/extraction kinetics.
► Li4Ti4.9Zr0.1O12 exhibits a good fast charge–discharge performance.