Preparation and Performance of Hollow Spherical Li₄Ti₅O₁₂ Doped by Mg²⁺

Abstract

The microstructure and performance of Li₄Ti₅O₁₂ doped by Mg prepared by hydrothermal method and solid phase method were investigated. Lithium dihydrate, magnesium acetate and tetrabutyl titanate were used as the main raw materials. This study reveals that Mg²⁺ has influences on the spherical structure, crystal development of Li₄Ti₅O₁₂ and the electrochemical performances. The hollow spherical structure is composed of nano-sheet structure and the nano-sheet structure can be affected by the Mg²⁺ content. For Li4-xMgxTi₅O₁₂, the sheet structure can be refined with the increment of Mg²⁺ content when x value is 0-0.1 and coarsen with the increment of Mg²⁺ content when x value is 0.1-0.2. The hollow spherical Li₄Ti₅O₁₂ powders prepared by hydrothermal method have better performance. The optimal Mgdoped amount of hydrothermal method is 0.1. At 0.1C, the first discharge capacity of Li3.9Mg0.1Ti₅O₁₂ prepared through hydrothermal method at 0.1C and 10 cycles is 182 and 178 mA h g⁻¹, respectively.

Keywords

hydrothermal method / hollow spherical Li₄Ti₅O₁₂ / nano-particles / Mg-doped / cycle Performance