期刊
ENERGY STORAGE MATERIALS
卷 26, 期 -, 页码 32-39出版社
ELSEVIER
DOI: 10.1016/j.ensm.2019.12.026
关键词
Na-ion batteries; Co-intercalation mechanism; Graphite; Diglyme; Irreversible capacity
资金
- National Natural Science Foundation of China [21972049]
- Guangdong Program [2015TQ01N870, 2017B030306013]
- Science and Technology Planning Project of Guangdong Province [2017B090901020]
While sodium ion (Na+) itself cannot intercalate into graphitic structure to form binary graphite-intercalation-compounds (GICs) as its alkaline brothers (lithium, potassium etc.) do, the intercalation of its solvated form [Na(solvent)(x)](+) can readily happen, leading to reversible formation of ternary GICs at stage 1, as long as used solvent molecules are stable against reduction, such as ethers. However, a mystery still remains: what causes the initial irreversible capacity loss given that co-intercalation requires an interphase-free surface? In this work, we answered this fundamental question by elaborately examining the solvation structures, desolvation process and the corresponding electrochemical reduction stability of ether-based solvated Na+. Based on the understanding, a simple and effective approach was proposed to significantly increase the initial coulombic efficiency of sodium-ether co-intercalation. Such precise control over solvation-sheath and interfacial structures provides molecular-level guidance to the designing of new electrolyte systems and graphite-intercalation chemistries.
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