(Invited) NMR Studies of SEI Coatings on Silicon

Wednesday, 4 October 2017: 08:00
National Harbor 1 (Gaylord National Resort and Convention Center)
Y. Jin, N. J. Kneusels, L. Marbella, G. Kim, E. Castillo-Martínez, P. C. M. M. Magusin, and C. P. Grey (Department of Chemistry, University of Cambridge)
The use of a wide variety of NMR spectroscopy techniques to characterise the SEI that is formed on silicon on cycling will be described. We have synthesized 13C enriched forms of additives such as FEC, which have allowed detailed structural studies to be performed. The results have been compared to the species identified in prior work on products formed on reducing FEC with lithium naphthalenide.1 Dynamic nuclear polarization approaches allow two dimensional experiments to be performed in reasonable timeframes helping to assign the different species observed in the 13C and 1H NMR spectroscopy. Studies of coated silicon samples will be presented.

  1. Michan, A. L.; Parimalam, B. S.; Leskes, M.; Kerber, R. N.; Yoon, T.; Grey, C. P.; Lucht, B. L. “Fluoroethylene Carbonate and Vinylene Carbonate Reduction: Understanding Lithium-Ion Battery Electrolyte Additives and Solid Electrolyte Interphase Formation” Chem. Mater., 2016, 28, 8149.