An in‐depth study of the solid electrolyte interphase compositional evolution in sodium‐Ion batteries: unravelling the effects of a Na metal counter electrode on the SEI
Author(s)
Type
Journal Article
Abstract
A comprehensive understanding of the solid electrolyte interphase (SEI) is crucial for ensuring long-term battery stability. This is particularly pertinent in sodium-ion batteries (NIBs), where the SEI remains poorly understood, and investigations are typically undertaken in half-cell configurations with sodium metal as the counter electrode. Na metal is known to be highly reactive with common carbonate-based electrolytes; nevertheless, its effects on SEI formation at the working electrode are largely unexplored. This work investigates the evolution of the SEI in NIBs during cycling, with an emphasis on the consequences of using a sodium metal counter electrode. Advanced analytical techniques, including hard X-ray photoelectron spectroscopy (HAXPES) and time-of-flight secondary ion mass spectrometry (ToF-SIMS), are used to obtain depth-resolved insights into the chemical composition and structural changes of the SEI on hard carbon anodes during cycling. The findings demonstrate that the cell configuration has a significant impact on SEI evolution and, by extension, battery performance. These findings suggest that full-cell studies are necessary to better simulate practical operating conditions, challenging traditional half-cell experiments.
Date Issued
2025-08-28
Date Acceptance
2025-06-01
Citation
Advanced Science, 2025, 12 (32)
ISSN
2198-3844
Publisher
Wiley
Journal / Book Title
Advanced Science
Volume
12
Issue
32
Copyright Statement
© 2025 The Author(s). Advanced Science published by Wiley-VCH GmbH This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
License URL
Identifier
10.1002/advs.202504717
Publication Status
Published
Article Number
e04717
Date Publish Online
2025-06-23