Sphere-like TiO2/Si anode material with superior performance for lithium ion batteries

The practical application of a titanium dioxide (TiO2) anode is restricted by the poor intrinsic ionic diffusion property and low theoretical capacity. Herein, sphere-like TiO2/Si nanoparticles were synthesized via a facile sol-gel method. Owing to the nano-spherical structure and the introduction of Si, the as-prepared TiO2/Si composite exhibits enhanced reversible capacity. Nanostructure of both TiO2 and Si materials provides short Li+ transmission pathways and high diffusion dynamics. The optimum ratio effectively alleviates the volume change of Si nanoparticles. The optimal mass ratio of TiO2/Si is 1:0.15, in which the composite electrode delivers excellent cycling life and rate performance, specifically, reversible capacity of 720.9 mAh g−1 at a current density of 100 mA g−1 and excellent long-term cycling stability with a capacity retention of 86.5% over 400 cycles.