A comprehensive understanding of the solid–electrolyte interphase (SEI) composition is crucial to developing high-energy batteries based on lithium metal anodes. A particularly contentious issue concerns the presence of LiH in the SEI. Here we report on the use of synchrotron-based X-ray diffraction and pair distribution function analysis to identify and differentiate two elusive components, LiH and LiF, in the SEI of lithium metal anodes. LiH is identified as a component of the SEI in high abundance, and the possibility of its misidentification as LiF in the literature is discussed. LiF in the SEI is found to have different structural features from LiF in the bulk phase, including a larger lattice parameter and a smaller grain size (<3 nm). These characteristics favour Li+ transport and explain why an ionic insulator, like LiF, has been found to be a favoured component for the SEI. Finally, pair distribution function analysis reveals key amorphous components in the SEI.
|Number of pages||6|
|Publication status||Published - 2021 May|
Bibliographical noteFunding Information:
The work done at Brookhaven National Laboratory was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Vehicle Technology Office of the US Department of Energy (DOE) through the Advanced Battery Materials Research (BMR) Program, including Battery500 Consortium under contract no. DE-SC0012704. The work done at Pacific Northwest National Laboratory was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies of the US DOE through the Advanced Battery Materials Research (BMR) Program (Battery500 Consortium) under contract no. DE-AC02-05CH11231. The work at the Army Research Laboratory was performed under JCESR, an Energy Research Hub funded by Basic Energy Sciences, US DOE. This research used beamline 28-ID-2 of the National Synchrotron Light Source II, a US DOE Office of Science user facility operated for the DOE Office of Science by Brookhaven National Laboratory under contract no. DE-SC0012704.
© 2021, The Author(s), under exclusive licence to Springer Nature Limited.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics
- Biomedical Engineering
- Materials Science(all)
- Condensed Matter Physics
- Electrical and Electronic Engineering