中国物理B ›› 2019, Vol. 28 ›› Issue (6): 68201-068201.doi: 10.1088/1674-1056/28/6/068201
• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇 下一篇
Hao Lu(陆浩), Junyang Wang(汪君洋), Bonan Liu(刘柏男), Geng Chu(褚赓), Ge Zhou(周格), Fei Luo(罗飞), Jieyun Zheng(郑杰允), Xiqian Yu(禹习谦), Hong Li(李泓)
Hao Lu(陆浩)1,2, Junyang Wang(汪君洋)1,2, Bonan Liu(刘柏男)3, Geng Chu(褚赓)4, Ge Zhou(周格)1,2, Fei Luo(罗飞)5, Jieyun Zheng(郑杰允)1,2, Xiqian Yu(禹习谦)1,2, Hong Li(李泓)1,2
摘要:
Silicon monoxide (SiO) has been considered as one of the most promising anode materials for next generation high-energy-density Li-ion batteries (LiBs) thanks to its high theoretical capacity. However, the poor intrinsic electronic conductivity and large volume change during lithium intercalation/de-intercalation restrict its practical applications. Fabrication of SiO/C composites is an effective way to overcome these problems. Herein, a series of micro-sized SiO@C/graphite (SiO@C/G) composite anode materials, with designed capacity of 600 mAh·g-1, are successfully prepared through a pitch pyrolysis reaction method. The electrochemical performance of SiO@C/G composite anodes with different carbon coating contents of 5 wt%, 10 wt%, 15 wt%, and 35 wt% is investigated. The results show that the SiO@C/G composite with 15-wt% carbon coating content exhibits the best cycle performance, with a high capacity retention of 90.7% at 25 ℃ and 90.1% at 45 ℃ after 100 cycles in full cells with LiNi0.5Co0.2Mn0.3O2 as cathodes. The scanning electron microscope (SEM) and electrochemistry impedance spectroscopy (EIS) results suggest that a moderate carbon coating layer can promote the formation of stable SEI film, which is favorable for maintaining good interfacial conductivity and thus enhancing the cycling stability of SiO electrode.
中图分类号: (Lithium-ion batteries)