Sol-gel Synthesis and Electrochemical Performance of Li4-xMgxTi5-xZrxO12 Anode Material for Lithium-ion Batteries

The anode materials Li4-xMgxTi5-xZrxO12 (x=0, 0.05, 0.1) were successfully synthesized by sol-gel method using Ti(OC4H9)4, CH3COOLi center dot 2H2O, MgCl2 center dot 6H2O and Zr(NO3)3 center dot 6H2O as raw materials. The crystalline structure, morphology and electrochemical properties of the as-prepared materials were characterized by XRD, SEM, cyclic voltammograms (CV), electrochemical impedance spectroscopy (EIS) and charge-discharge cycling tests. The results show that the lattice parameters of the Mg-Zr doped samples are slightly larger than that of the pure Li4Ti5O12, and Mg-Zr doping does not change the basic Li4Ti5O12 structure. The rate capability of Li4-xMgxTi5-xZrxO12 (x=0.05, 0.1) electrodes is significantly improved due to the expansile Li+ diffusion channel and reduced charge transfer resistance. In this study, Li3.95Mg0.05Ti4.95Zr0.05O12 represented a relatively good rate capability and cycling stability, after 400 cycles at 10 C, the discharge capacity retained as 134.74 mAh center dot g-1 with capacity retention close to 100%. The excellent rate capability and good cycling performance make Li3.95Mg0.05Ti4.95Zr0.05O12 a promising anode material in lithium-ion batteries.