Uniform Nano-Sn/C Composite Anodes for Lithium Ion Batteries
详细信息 查看全文
- 作者：Yunhua Xu ; Qing Liu ; Yujie Zhu ; Yihang Liu ; Alex Langrock ; Michael R. Zachariah ; Chunsheng Wang
- 刊名：Nano Letters
- 出版年：2013
- 出版时间：February 13, 2013
- 年：2013
- 卷：13
- 期：2
- 页码：470-474
- 全文大小：291K
- 年卷期：v.13,no.2(February 13, 2013)
- ISSN：1530-6992
文摘
Nano-Sn/C composites are ideal anode materials for high energy and power density Li-ion batteries. However, because of the low melting point of Sn and the tendency of grain growth, especially during high temperature carbonization, it has been a significant challenge to create well-dispersed ultrasmall Sn nanoparticles within a carbon matrix. In this paper, we demonstrate an aerosol spray pyrolysis technique, as a facile and scalable method, to synthesize a nano-Sn/C composite with uniformly dispersed 10 nm nano-Sn within a spherical carbon matrix. The discharge capacity of nano-Sn/C composite sphere anodes maintains the initial capacity of 710 mAh/g after 130 cycles at 0.25 C. The nano-Sn/C composite sphere anodes can provide 600 mAh/g even at a high rate of 20 C. To the best of our knowledge, such high rate performance for Sn anodes has not been reported previously. The exceptional performance of the nano-Sn/C composite is attributed to the unique nano-Sn/C structure: (1) carbon matrix offers mechanical support to accommodate the stress associated with the large volume change of nano-Sn, thus alleviating pulverization; (2) the carbon matrix prevents Sn nanoparticle agglomeration upon prolonged cycling; and (3) carbon network provides continuous path for Li ions and electrons inside the nano-Sn/C composite spheres.