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DOE OSTI · 1840024

Engineering the Si Anode Interface via Particle Surface Modification: Embedded Organic Carbonates Lead to Enhanced Performance

Jiang, Sisi·Yang, Zhenzhen·Liu, Yuzi·Johnson, Noah·Bloom, Ira·Zhang, Lu·Zhang, Zhengcheng
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Abstract

Si nanoparticles (SiNPs) are recognized as a promising anode material for next-generation high-energy lithium-ion batteries. However, due to the more stringent requirements resulting from severe volume change, the solid-electrolyte interphase (SEI) on SiNPs plays a critical role in determining their cycling performance. Engineering the interface for higher stability has become an effective yet challenging approach to accommodate the deterioration of the silicon anode from the repeated lithiation/delithiation process. Herein, we report a novel approach of engineering a covalently bonded organic monolayer of ethylene carbonates onto the surface of the SiNPs that can help form a sturdy SEI. Finally, this molecule-level surface modification provides an effective approach to enable high-energy lithium-ion batteries with Si anodes.

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25 ENERGY STORAGESi nanoparticleshydrosilylation reactionsolidelectrolyte-interfacesurface organic carbonate group

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Jiang, Sisi, Yang, Zhenzhen, Liu, Yuzi, Johnson, Noah, Bloom, Ira, Zhang, Lu, Zhang, Zhengcheng. 2021-08-09. Engineering the Si Anode Interface via Particle Surface Modification: Embedded Organic Carbonates Lead to Enhanced Performance. https://doi.org/10.1021/acsaem.1c00374

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