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DOE OSTI · 1757963

Apparent Increasing Lithium Diffusion Coefficient with Applied Current in Graphite

Dees, Dennis W.·Rodrigues, Marco-Tulio F.·Kalaga, Kaushik·Trask, Stephen E.·Shkrob, Ilya A.·Abraham, Daniel P.·Jansen, Andrew N.
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Abstract

In this study, we assert that the apparent lithium diffusion coefficient in graphite active particles in the negative electrodes of lithium-ion cells increases appreciably with the intercalation rate. This assertion is based on an electrochemical model analysis of a wide range of electrochemical micro-reference electrode full cell studies on a coated natural graphite and other literature results. Although the mechanism for this increase is a subject of further investigation, the results of our study suggest that the lithium transport in the graphite does not limit the maximum attainable charging rate in typical lithium-ion cells for electric vehicles.

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25 ENERGY STORAGEgraphite electrode active materiallithium diffusion ratelithium-ion battery

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Dees, Dennis W., Rodrigues, Marco-Tulio F., Kalaga, Kaushik, Trask, Stephen E., Shkrob, Ilya A., Abraham, Daniel P., Jansen, Andrew N.. 2020-08-28. Apparent Increasing Lithium Diffusion Coefficient with Applied Current in Graphite. https://doi.org/10.1149/1945-7111%2Fabaf9f

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