Ag-doped Li2ZnTi3O8 as a high rate anode material for rechargeable lithium-ion batteries

作者：Tang Haoqing^*; Tang Zhiyuan; Du Chenqiang; Qie Fuchang; Zhu Jiangtao

来源：Electrochimica Acta, 2014, 120: 187-192.

DOI：10.1016/j.electacta.2013.12.090

• Lithium zinc titanate
• Ag-doped
• anode materials
• lithium-ion batteries

Ag-doped Li2ZnTi3O8 in the form of Li2ZnAgxTi3-xO8 (X = 0.05, 0.1, 0.15 and 0.2) and un-doped Li2ZnTi3O8 are successfully synthesized by high-energy ball-milling assisted solid-state reaction method. The structures, morphologies and electrochemical properties of the as-prepared materials are tested by different physical and electrochemical methods. The results of characterization show that a part of Ag ions replace Ti ions and the remaining Ag particles adhere to the surface of Li2ZnTi3O8 grains. In addition, doping Ag does not change the basic spinel structure of Li2ZnTi3O8. Galvanostatic charge/discharge tests denote that the Li2ZnAg0.15Ti2.85O8 composite has the highest initial discharge capacity of 214.0 mAh g(-1) at 0.1 A g(-1), and shows good high rate performance at current densities of 1.0 A g(-1) and 2.0 A g(-1) in all as-prepared samples. It is shown by CV that the Li2ZnAg0.15Ti2.85O8 composite has the lowest polarization. Electrochemical impedance spectroscopy reveals that the Li2ZnAg0.15Ti2.85O8 sample exhibits higher electronic conductivity and faster lithium ion diffusivity compared with pure Li2ZnTi3O8. The significant improvements at high rate performance demonstrate that Ag-doped Li2ZnTi3O8 (x = 0.15) is a promising high rate anode material for rechargeable lithium-ion batteries.

• 出版日期2014-2-20
• 单位天津大学