Comparative study of Li2ZnTi3O8 anode material with good high rate capacities prepared by solid state, molten salt and sol–gel methods

Abstract

Cubic spinel Li2ZnTi3O8 is a promising lithium ion battery electrode anode material with high specific lithium-intercalation capacity and low discharge voltage platform. Herein, Li2ZnTi3O8 anode materials are synthesized through solid state reaction, molten salt route, and sol–gel method, respectively. Sol–gel formed Li2ZnTi3O8 exhibits good crystallinity from XRD and agglomeration is alleviated with uniform particle size and more stack holes from SEM images compared with other methods. Cyclic voltammograms (CV) results show that the sol–gel formed Li2ZnTi3O8 electrode has the lowest polarization, indicating better kinetic process. Electrochemical impedance spectroscopy (EIS) reveals that the sol–gel formed Li2ZnTi3O8 sample exhibits highest electronic conductivity and faster lithium ion diffusivity in all three samples. The sol–gel formed Li2ZnTi3O8 electrode has excellent long-term cycling performance and high discharge capacities of 71.2, 90.9, and 150.0mAhg−1 after 1000 charge–discharge cycles with low capacity fadings of only 0.058%, 0.051%, and 0.028% per cycle, at 3000, 2000, and 1000mAg−1, respectively. These results show that sol–gel formed Li2ZnTi3O8 is a promising anode electrode material for high performance lithium ion batteries.