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DOE OSTI · 1469920

Silicon Composite Electrodes with Dynamic Ionic Bonding

Kang, Sen·Yang, Ke·White, Scott R.·Sottos, Nancy R.
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Abstract

Silicon (Si) composite electrodes are created with increased cycle lifetimes and reliability through dynamic ionic bonding between active Si nanoparticles and a polymer binder. Amine groups are covalently attached to Si nanoparticles via surface functionalization. Si composite electrodes are fabricated by combining the Si nanoparticles with a poly(acrylic acid) (PAA) binder. The formation of ionic bonds between amine groups on Si particles and carboxylic acid groups on the PAA binder is characterized by X-ray photoelectron spectroscopy and Raman spectroscopy. Si composite anodes with ionic bonding demonstrate long term cycling stability with capacity retention of 80% at 400 cycles at a current density of 2.1 A g –1 and good rate capability. Furthermore, the dynamic ionic bonds effectively mitigate the deterioration of electrical interfaces in the composite anodes as suggested by stable impedance over 300 cycles.

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25 ENERGY STORAGELi‐ion batteriesSi composite anodesionic bondingrestoration of electrical interfaces

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Kang, Sen, Yang, Ke, White, Scott R., Sottos, Nancy R.. 2017-05-12. Silicon Composite Electrodes with Dynamic Ionic Bonding. https://doi.org/10.1002/aenm.201700045

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