Facile fabrication of Li5Cr7Ti6O25@Li0.33La0.56TiO3 composites as promising anode materials for high-performance Li-ion batteries

Li5Cr7Ti6O25 has been considerd as a hopeful anode material of Li-ion batteries due to the low cost. Nonetheless, the intrinsically low conductivity obviously reduces reversible capacity and cycle performance. In this work, we design Li5Cr7Ti6O25@Li0.33La0.56TiO3 (LCTO@LLTO) composites by simple ball-milling process followed by a post-calcination at air atmosphere, which realizes an excellent cycle performance. The Li0.33La0.56TiO3 (LLTO) coating does not alter the morphology and particle size of the Li5Cr7Ti6O25 (LCTO) material, but increses the lattice parameter. The right level LLTO modification can improve the transfer ability of ions and electrons with enhanced lithiation/delithiation dynamics, making a good cycling stability and rate capability of as-prepared LCTO anode. As a result, LCTO@LLTO(5 wt%) shows a high charge capacity of 149.8 mAh g-1 even at 1C in the 50th cycle, much higher than that LCTO with a capacity of 126.3 mAh g-1. The improved electrochemical performance of LCTO@LLTO composites can be attribute to the enhanced Li ion diffusion kinetics, electrochemical reversibility and ion conductivity by LLTO modification. Therefore, the LLTO modificationcan be regarded as an efficient way for construct the anode materials for high-perfprmance Li-ion batteries.