期刊
APPLIED PHYSICS LETTERS
卷 108, 期 21, 页码 -出版社
AMER INST PHYSICS
DOI: 10.1063/1.4952434
关键词
-
资金
- Bundesministerium fur Bildung and Forschung (BMBF)
Li2S is the final product of lithiation of sulfur cathodes in lithium-sulfur (Li-S) batteries. In this work, we study formation and diffusion of defects in Li2S. It is found that for a wide range of voltages (referenced to metal Li) between 0.17V and 2.01 V, positively charged interstitial Li (Li+) is the most favorable defect type with a fixed formation energy of 1.02 eV. The formation energy of negatively charged Li vacancy (V-Li(-)) is also constant, and it is only 0.13 eV higher than that of Li+. For a narrow range of voltages between 0.00V and 0.17 V, the formation energy of neutral S vacancy is the lowest and it decreases with decreasing the cell voltage. The energy barrier for Li+ diffusion (0.45 eV), which takes place via an exchange mechanism, is 0.18 eV higher than that for V-Li(-) (0.27 eV), which takes place via a single vacancy hopping. Considering formation energies and diffusion barriers, we find that ionic conductivity in Li2S is due to both Li+ and V-Li(-), but the latter mechanism being slightly more favorable. Published by AIP Publishing.
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