(Invited) A Mesoscale Approach Toward Elucidating Microstructure-Transport-Performance Interaction in Li-S Battery Electrodes

Lithium-sulfur (Li-S) battery is a promising energy storage technology, which offers improved performance in terms of higher energy density and material sustainability owing to the abundance of sulfur (S) as the active material. However, one of the key challenges centers on insoluble discharge product formation in the cathode and concomitant internal shuttle effect [1-5]. The polysulfide (such as Li₂S) formation poses a deleterious consequence on the electrode microstructural change, thereby impacting the transport and electrochemical properties and ultimately resulting in capacity fade.

In this regard, the cathode architecture plays an important role in determining the Li-S battery performance. A desirable electrode microstructure should effectively deter the dissolution of polysulfide, and facilitate lithium ion transport. This warrants a fundamental understanding of the physicochemical interplay resulting from the underlying microstructure-transport-performance interaction.

In this work, a mesoscale computational model, shown schematically in Fig.1, will be presented in order to fundamentally investigate the morphology evolution due to Li₂S precipitation and the resulting influence on the electrode microstructural and performance attributes.

Acknowledgement:

Financial support from the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, grant DE-EE0006832 (Program manager: Dr. Tien Duong) is gratefully acknowledged.

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