Self-assembled synthesis of nanoflower-like Li4Ti5O12 for ultrahigh rate lithium-ion batteries

Nanoflower-like spinel lithium titanate is synthesized through combining sol/gel and hydrothermal process. The role of hydrothermally treating amorphous TiO2 beads under the additive of LiOH precursor can derive nanocrystalline spinel lithium titanate with nanoflower-like shape. Afterward, calcination helps the formation of nanoflower-like spinet lithium titanate. The crystalline structure and morphological observation of the as-synthesized nanoflower-like Li4Ti5O12 are characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The nanoflower-like structure can be revealed through the N-2 adsorption/desorption isotherm. It is demonstrated that the electrochemical performance is significantly improved by the architecture control. The nanoflower-like spinel lithium titanate shows outstanding cycling behavior of 148, 143, 141, 138, 133, 126, 118 mA h g(-1) at 0.5, 1, 3, 5, 10, 20, 30 C, respectively. The reversible capacity at 30 C even remains over 80% of that at 0.5 C. The superior C-rate performance is associated with the nanoflower-like structure, facilitating lithium transportation ability during cycling. It is believed that the novel self-assembled synthesis for nanoflower-like lithium titantate can exhibit an excellent cycling performance and can be a good candidate for the next-generation anode material of ultrahigh rate Li-ion batteries for the application of electric vehicles. (C) 2012 Elsevier B.V. All rights reserved.