期刊
MICROPOROUS AND MESOPOROUS MATERIALS
卷 275, 期 -, 页码 42-49出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/j.micromeso.2018.08.014
关键词
Lithium-ion battery; Silicon anode; Core-shell structure; CVD method
类别
资金
- National Natural Science Foundation of China [21371149, 21671168]
- Natural Science Foundation of Hebei Province [17964403D, B2016203498]
The theoretical capacity of the silicon electrode is very high, but the large volume change of Si during the charge and discharge processes leads to a fast capacity fading and thus a poor cycling stability. Here, in order to overcome this shortcoming, a new method for preparing silicon electrode materials was proposed. We employed a facile Chemical Vapor Deposition (CVD) process to produce uniform carbon layer to cover the silicon spheres, etched a space between the carbon layer and the silicon nucleus to accommodate the expansion of silicon during charging and discharging, and thus a well-designed chain-like Si@void@C electrode material was prepared. The thickness of the carbon shell was tuned simply by adjusting CVD deposition time. The stability of such silicon electrode was proved to be significantly enhanced. By a comparative study on Si@void@C, Si@C and the commercial pure Si without carbon coating, we have demonstrated that the thin but stable carbon shell and the rationally designed void space in the Si@void@C structure have greatly positive influences on the electrochemical performance. As a result, the chain-like Si@void@C-15 exhibits a reversible capacity of 983 mA h g(-1) after 200 cycles and a high capacity retention up to 94%, indicating an excellent cycling stability. Good rate performance is also demonstrated.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据