中国物理B ›› 2020, Vol. 29 ›› Issue (6): 68202-068202.doi: 10.1088/1674-1056/ab943c
• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇 下一篇
Understanding the Li diffusion mechanism and positive effect of current collector volume expansion in anode free batteries
Yan Zhuang(庄严), Zheyi Zou(邹喆乂), Bo Lu(吕浡), Yajie Li(李亚捷), Da Wang(王达), Maxim Avdeev, Siqi Shi(施思齐)
- 1 State Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of Advanced Ferrometallurgy, School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China;
2 Materials Genome Institute, Shanghai University, Shanghai 200444, China;
3 Shanghai Institute of Applied Mathematics and Mechanics, School of Mechanics and Engineering Science, Shanghai University, Shanghai 200444, China;
4 Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai University, Shanghai 200444, China;
5 Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC NSW 2232, Australia;
6 School of Chemistry, The University of Sydney, Sydney 2006, Australia
Understanding the Li diffusion mechanism and positive effect of current collector volume expansion in anode free batteries
Yan Zhuang(庄严)1, Zheyi Zou(邹喆乂)1, Bo Lu(吕浡)3,4, Yajie Li(李亚捷)1, Da Wang(王达)1, Maxim Avdeev5,6, Siqi Shi(施思齐)1,2
- 1 State Key Laboratory of Advanced Special Steel, Shanghai Key Laboratory of Advanced Ferrometallurgy, School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China;
2 Materials Genome Institute, Shanghai University, Shanghai 200444, China;
3 Shanghai Institute of Applied Mathematics and Mechanics, School of Mechanics and Engineering Science, Shanghai University, Shanghai 200444, China;
4 Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai University, Shanghai 200444, China;
5 Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC NSW 2232, Australia;
6 School of Chemistry, The University of Sydney, Sydney 2006, Australia
摘要：
In anode free batteries (AFBs), the current collector acts as anode simultaneously and has large volume expansion which is generally considered as a negative effect decreasing the structural stability of a battery. Moreover, despite many studies on the fast lithium diffusion in the current collector materials of AFB such as copper and aluminum, the involved Li diffusion mechanism in these materials remains poorly understood. Through first-principles calculation and stress-assisted diffusion equations, here we study the Li diffusion mechanism in several current collectors and related alloys and clarify the effect of volume expansion on Li diffusion respectively. It is suggested that due to the lower Li migration barriers in aluminum and tin, they should be more suitable to be used as AFB anodes, compared to copper, silver, and lead. The Li diffusion facilitation in copper with a certain number of vacancies is proposed to explain why the use of copper with a thickness ≤ 100 nm as the protective coating on the anode improves the lifetime of the batteries. We show that the volume expansion has a positive effect on Li diffusion via mechanical-electrochemical coupling. Namely, the volume expansion caused by Li diffusion will further induce stress which in turn affects the diffusion. These findings not only provide in-depth insight into the operating principle of AFBs, but also open a new route toward design of improved anode through utilizing the positive effect of mechanical-electrochemical coupling.
中图分类号: (Lithium-ion batteries)
- 82.47.Aa