Double carbon decorated lithium titanate as anode material with high rate performance for lithium-ion batteries

Spinel lithium titanate (Li₄Ti₅O₁₂) has the advantages of structural stability, however it suffers the disadvantages of low lithium-ion diffusion coefficient as well as low conductivity. In order to solve issues, we reported a simple method to prepare carbon-coated Li₄Ti₅O₁₂/CNTs (C@Li₄Ti₅O₁₂/CNTs) using stearic acid as surfactant and carbon source to prepare carbon coated nanosized particles. The obtained Li₄Ti₅O₁₂ particles of 100 nm in size are coated with the carbon layers pyrolyzed from stearic acid and dispersed in CNTs matrix homogeneously. These results show that the synthesized C@Li₄Ti₅O₁₂/CNTs material used as anode materials for lithium ion batteries, presenting a better high-rate performance (147 mA h g⁻¹ at 20 C). The key factors affecting the high-rate properties of the C@Li₄Ti₅O₁₂/CNTs composite may be related to the synergistic effects of the CNTs matrix and the carbon- coating layers with conductivity enhancement. Additionally, the amorphous carbon coating is an effective route to ameliorate the rate capability of Li₄Ti₅O₁₂/CNTs.