锂钛复合氧化物锂离子电池负极材料的研究

采用 3种化学方法合成锂钛复合氧化物 .应用X -射线衍射分析对其结构进行表征以及电化学性能测试 ,结果表明 :由Li2 CO3、TiO2 高温合成的锂钛复合氧化物为尖晶石结构的Li4Ti5 O12 .Li4Ti5 O12 电极在 1 .5V左右有一放电平台 ,充放电可逆性良好 ,即充电电压平台与此接近 ,且电极的比容量较大 ,循环性能良好 .以 0 .30mA·cm- 2 充放电时 ,首次放电容量可达 30 0mAh·g- 1,可逆比容量为 1 0 0mAh·g- 1,经多次充放电循环后 ,其结构仍保持稳定性 .试验电池测试表明 ,Li4Ti5 O12 可选作Li4Ti5 O12 /LiCoO2 锂离子电池的负极材料 .

The Study on Lithiated Titanium Composite Oxides as Negative Electrode for Lithium-Ion Battery

Lithiated titanium composite oxides Li 4Ti 5O 12 were prepared from Li 2CO 3 and TiO 2. The XRD results of this composite oxides indicated that the compound had a spinel structure. The electrochemical behavior of lithiated titanium composite oxides was examined. The results showed that this material had an excellent cyclic capability and reversibility for lithium insertion, and had high specific capacity: the initial discharge capacity was 300 mAh·g -1 , and the reversible capacity was 100 mAh·g -1 . The discharge plateau (about 1.5 V) and the charge plateau (about 1.6 V) were very close on the voltage curves. X_ray diffraction results showed that the base structure of Li 4Ti 5O 12 did not change during the insertion process of lithium into the material. This material was stable for lithium insertion and extraction. The charge and the discharge results of tentative lithium_ion battery Li 4Ti 5O 12 ｜l mol·L -1 LiClO 4_PC｜LiCoO 2 indicated that Li 4Ti 5O 12 was a candidate material of negative electrode for lithium_ion batteries.