| 锂离子电池负极材料Li4-xKxTi5O12结构和电化学性能 |
| Structural and Electrochemical Characteristics of Li4-xKxTi5O12 as Anode Material for Lithium-Ion Batteries |
|
| 摘要: 采用固相反应的方法制备了尖晶石型Li4Ti5O12和K掺杂Li4-xKxTi5O12(x=0.02，0.04，0.06)。通过XRD、SEM、BET等对制备材料进行了分析。结果表明，K掺杂没有影响立方尖晶石型Li4Ti5O12的合成，同时也没有改变Li4Ti5O12的电化学反应过程。K掺杂Li4-xKxTi5O12具有比Li4Ti5O12小的颗粒粒径和比Li4Ti5O12大的比表面积、孔容积。适量的K掺杂能够明显改善Li4Ti5O12的电化学性能，尤其是倍率性能，但是过多的K掺杂却不利于材料电化学性能的提高。研究表明，Li3.96K0.04Ti5O12体现了相对较好的倍率性能和循环稳定性。0.5C下，首次放电比容量为161 mAh·g-1，3.0和5.0C下，容量保持分别为138和121 mAh·g-1。3.0C下，200次循环后容量保持为137 mAh·g-1。 |
| 关键词: 锂离子电池 负极材料 尖晶石型钛酸锂 掺杂 |
| 基金项目: |
| Abstract: The spinel Li4Ti5O12 and K-doped Li4-xKxTi5O12(x=0.02, 0.04, 0.06) were prepared by a solid state reaction. X-ray powder diffraction (XRD), scanning electronic microscopy (SEM) and Brunau-Emmertt-Teller (BET) were employed to characterize the synthesized materials. The results indicated that K-doping did not affect the synthesis of the cubic spinel Li4Ti5O12. Furthermore, the K-doping did not change the electrochemical reaction process of Li4Ti5O12. The K-doped Li4-xKxTi5O12(x=0.02, 0.04, 0.06) had smaller particle size, larger specific surface area and hole cubage than the pristine Li4Ti5O12 without K doping. An appropriate amount of K doping was favorable to the electrochemical performances, and in particular the rate capability of Li4Ti5O12. However, a high amount of Zr-doping was adverse. The research suggested that Li3.96K0.04Ti5O12 exhibited a relatively good rate capability and cycling stability. At the charge-discharge rate of 0.5C, 3.0C and 5.0C, its discharge capacities were 161, 138 and 121 mAh·g-1, respectively. After 200 cycles at 3.0C, its discharge capacity remained at 137 mAh·g-1. |
| Keywords: lithium-ion battery anode material spinel lithium titanate doping |
| |
| 摘要点击次数: 1762 |
| 全文下载次数: 1806 |
| 李 星,瞿美臻,于作龙.锂离子电池负极材料Li4-xKxTi5O12结构和电化学性能[J].无机化学学报,2010,26(2):233-239. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
| Support information: |
|
|
|
|
|
|
