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arXiv · 1606.06363

In situ AFM Observations of Li-Oxygen Electrochemical Reactions

Hariharan Katharajan·Kumar Virwani·A. David Erpelding·Jeannette M. Garcia
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Abstract

The morphologies of crystalline lithium peroxide (Li2O2) discharge products in Li-O2 batteries have been shown to exhibit a dependency on subtle variations within the battery cell-operating environment including exposure to ambient air, moisture, or additives. As a result, imaging battery discharge products in real time under carefully controlled environmental conditions is a challenging obstacle for complete mechanistic understanding of Li2O2 growth and deposition during discharge in metal-air batteries. Here, we report the design of a completely enclosed cell for high-resolution in situ AFM imaging of Li-O2 battery discharge products. The air-and moisture-free electrochemical cell environment enabled the observation of different product morphologies during AFM imaging when LiTFSI in oxygen-saturated tetraethylene glycol dimethyl ether (tetraglyme) solvent was employed. This in situ AFM cell development brings complimentary information to various proposed mechanisms for lithium oxygen reaction.

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Hariharan Katharajan, Kumar Virwani, A. David Erpelding, Jeannette M. Garcia. 2016-06-20. In situ AFM Observations of Li-Oxygen Electrochemical Reactions. https://arxiv.org/abs/1606.06363

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