Revealing solid electrolyte interphase formation through interface-sensitive Operando X-ray absorption spectroscopy

DOI: 10.1038/s41467-022-33691-1

Authors: Jack E. N. Swallow (University of Oxford; Diamond Light Source; The Faraday Institution) , Michael W. Fraser (University of Oxford; The Faraday Institution) , Nis-Julian H. Kneusels (University of Cambridge) , Jodie F. Charlton (University of Oxford; Diamond Light Source) , Christopher G. Sole (Diamond Light Source; The Faraday Institution) , Conor M. E. Phelan (University of Oxford) , Erik Bjorklund (University of Oxford; The Faraday Institution) , Peter Bencok (Diamond Light Source) , Carlos Escudero (ALBA Synchrotron Light Source) , Virginia Perez-Dieste (ALBA Synchrotron Light Source) , Clare P. Grey (University of Cambridge) , Rebecca J. Nicholls (University of Oxford) , Robert S Weatherup (University of Cambridge; Diamond Light Source; The Faraday Institution)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nature Communications , VOL 13

State: Published (Approved)
Published: October 2022
Diamond Proposal Number(s): 25647 , 29213 , 30816

Abstract: The solid electrolyte interphase (SEI) that forms on Li-ion battery anodes is critical to their long-term performance, however observing SEI formation processes at the buried electrode-electrolyte interface is a significant challenge. Here we show that operando soft X-ray absorption spectroscopy in total electron yield mode can resolve the chemical evolution of the SEI during electrochemical formation in a Li-ion cell, with nm-scale interface sensitivity. O, F, and Si K-edge spectra, acquired as a function of potential, reveal when key reactions occur on high-capacity amorphous Si anodes cycled with and without fluoroethylene carbonate (FEC). The sequential formation of inorganic (LiF) and organic (-(C=O)O-) components is thereby revealed, and results in layering of the SEI. The addition of FEC leads to SEI formation at higher potentials which is implicated in the rapid healing of SEI defects and the improved cycling performance observed. Operando TEY-XAS offers new insights into the formation mechanisms of electrode-electrolyte interphases and their stability for a wide variety of electrode materials and electrolyte formulations.

Diamond Keywords: Batteries; Lithium-ion

Subject Areas: Materials, Energy, Chemistry


Instruments: B07-B-Versatile Soft X-ray beamline: High Throughput , I10-Beamline for Advanced Dichroism

Other Facilities: BL 24 (CIRCE) at ALBA

Added On: 17/10/2022 11:44

Documents:
s41467-022-33691-1.pdf

Discipline Tags:

Energy Storage Energy Physical Chemistry Energy Materials Chemistry Materials Science

Technical Tags:

Spectroscopy X-ray Absorption Spectroscopy (XAS)