Investigations of Fundamental Li-O2 Electrochemistry by In Situ Liquid Cell Transmission Electron Microscopy

原位液体电池透射电子显微镜研究基础 Li-O2 电化学

• 批准号: 18H05939
• 负责人: 韓 久慧
• 金额: $ 1.91万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Research Activity Start-up
• 财政年份: 2018
• 资助国家: 日本
• 起止时间: 2018-08-24 至 2020-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-18H05939/
• 关键词: 液体セル透過電子顕微鏡; リチウム空気電池; その場観察; 透過電子顕微鏡; Li-O2電気化学; 液体セル

Using in situ liquid cell transmission electron microscopy, we have successfully investigated the reaction dynamics of Li-O2 battery in real-time and real-space. The nanoscale reactions at the electrode-electrolyte interfaces, associated with the formation and decomposition of solid Li2O2 phase, were directly visualized. We found that discharge and charge rate can significantly affect the fundamental mechanisms of Li-O2 reactions. At low rates, the Li-O2 reaction proceeds via a solution mechanism with the formation of Li2O2 layers as thick as ~500 nm. While under high overpotential conditions, a very thin Li2O2 layer forms through a surface mechanism with fast passivation of the electrode surfaces. These findings have advanced our understandings of the fundamental Li-O2 electrochemistry.

利用原位液体电池透射电子显微镜，我们成功地研究了实时和真实空间的Li-O2电池的反应动力学。电极-电解质界面处与固体 Li2O2 相的形成和分解相关的纳米级反应被直接可视化。我们发现放电和充电速率可以显着影响Li-O2反应的基本机制。在低速率下，Li-O2 反应通过溶液机制进行，形成厚度约为 500 nm 的 Li2O2 层。在高过电势条件下，通过表面机制形成非常薄的 Li2O2 层，电极表面快速钝化。这些发现增进了我们对基本 Li-O2 电化学的理解。