Quantitative characterization of the ionic mobility and concentration in Li-battery cathodes via low frequency electrochemical strain microscopy†,Nanoscale

当前位置： X-MOL 学术 › Nanoscale › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Quantitative characterization of the ionic mobility and concentration in Li-battery cathodes via low frequency electrochemical strain microscopy†
Nanoscale ( IF 5.8 ) Pub Date : 2017-12-15 00:00:00 , DOI: 10.1039/c7nr08001h
D. O. Alikin _{1,

2,

3,

4,

5} , K. N. Romanyuk _{1,

2,

3,

4,

5} , B. N. Slautin _{1,

2,

3,

4} , D. Rosato _{6,

7,

8} , V. Ya. Shur _{1,

2,

3,

4} , A. L. Kholkin _{1,

2,

3,

4,

5}

Affiliation

Electrochemical strain microscopy (ESM) can provide useful information on the ionic processes in materials at the local scale. This is especially important for ever growing applications of Li-batteries whose performance is limited by the intrinsic and extrinsic degradation. However, the ESM method used so far has been only qualitative due to multiple contributions to the apparent ESM signal. In this work, we provide a viable approach for the local probing of ionic concentration and diffusion coefficients based on the frequency dependence of the ESM signal. A theoretical basis considering the dynamic behavior of ion migration and relaxation and change of ion concentration profiles under the action of the electric field of the ESM tip is developed. We argue that several parasitic contributions to the ESM signal discussed in the literature can be thus eliminated. The analysis of ESM images using the proposed approach allows a quantitative mapping of the ionic diffusion coefficients and concentration in ionic conductors. The results are validated on Li-battery cathodes (LiMn₂O₄) extracted from commercial Li-batteries and can provide novel possibilities for their development and further insight into the mechanisms of their degradation.

中文翻译：

通过低频电化学应变显微镜对锂电池阴极中离子迁移率和浓度的定量表征†

电化学应变显微镜（ESM）可以提供有关局部规模材料中离子过程的有用信息。这对于锂电池的不断增长的应用尤其重要，因为锂电池的性能受到内在和外在降解的限制。但是，由于对表观ESM信号的多种贡献，到目前为止使用的ESM方法仅是定性的。在这项工作中，我们基于ESM信号的频率依赖性为离子浓度和扩散系数的局部探测提供了一种可行的方法。建立了在ESM尖端电场作用下考虑离子迁移和弛豫以及离子浓度分布变化的动态行为的理论基础。我们认为可以消除文献中讨论的对ESM信号的几种寄生影响。使用提出的方法对ESM图像进行分析可以定量映射离子扩散系数和离子导体中的浓度。结果在锂电池正极（LiMn₂ O₄）提取自商用锂电池，可以为其发展提供新的可能性，并进一步了解其降解机理。

更新日期：2017-12-15

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11