Characterization of spherical-shaped Li₄Ti₅O₁₂ prepared by spray drying

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• 作者：Feixiang Wu ; Zhixing Wang ; Xinhai Li ; Huajun Guo ; Peng Yue ; Xunhui Xiong ; Zhenjiang He ; Qian Zhang
• 关键词：Lithium ion batteries ; Lithium titanate ; Nano-micron materials ; Anode material ; Spray drying
• 刊名：Electrochimica Acta
• 出版年：2012
• 出版时间：1 September, 2012
• 年：2012
• 卷：78
• 期：Complete
• 页码：331-339
• 全文大小：2177 K

文摘

This work introduces a novel solution system not slurry to synthesize nano-micron sized Li₄Ti₅O₁₂ by spray drying followed by solid-state calcination at several temperatures between 650 and 800 ¡ãC. Well-crystallized Li₄Ti₅O₁₂ with no impurity can be obtained at temperatures of 650, 700, 750 and 800  ¡ãC owing to the effect of nanoscale and uniform precursor powders. However, the spherical shape of the precursor powders is maintained after post-treatment at temperatures of 650 and 700 ¡ãC. Because of the rough and porous nano-micron sized spherical particles, the Li₄Ti₅O₁₂ obtained at relatively low calcined temperatures of 650 and 700 ¡ãC show better rate capabilities than them of the Li₄Ti₅O₁₂ obtained at higher temperatures of 750 and 800 ¡ãC. At the relatively low calcined temperature of 650 ¡ãC, the Li₄Ti₅O₁₂ shows the best electrochemical performance. The initial discharge capacities are 174.8, 170.5, 167.5, 165.3, 158.2, 152.1, 130.9 and 111.9 mAh g^?1 at the 0.1C, 0.5C, 1C, 2C, 5C, 10C, 15C and 20C rates, respectively. After 100 cycles, the as-prepared Li₄Ti₅O₁₂ retains 99.6 % , 96.9 % , 98.8 % , 89.3 % , 90.4 % and 89.0 % of its initial discharge capacities at the 1C, 2C, 5C, 10C, 15C and 20C rates, respectively.