Comparative analysis of cathode morphologies in structural batteries using X-ray absorption near edge spectroscopy (XANES) and electrochemical methods
Journal article, 2025
Structural batteries utilise the bifunctionality of carbon fibres to act as a load-bearing structure, but also as a conductive current collector for a battery electrode. Lithium-ion transport during the cycling of structural battery cathodes coated with different morphologies is investigated using Iron X-Ray Absorption Near Edge Spectroscopy (Fe XANES) and correlated to electrochemical performance. Two contrasting morphologies were produced using slurry coating and electrophoretic deposition (EPD) of lithium-iron phosphate (LFP) onto continuous carbon fibres. The ability to study the different structural battery cathode morphologies operando allows for a comparative analysis of their impact on cycling performance. The EPD-coated fibres exhibited a more homogeneous, thinner coating around the fibre compared to the thick, one-sided coating produced using slurry coating. Despite a lower initial capacity and 30 % lithium re-intercalation loss in the first cycle, EPD-coated fibres exhibited more stable capacity retention over time compared to slurry-coated counterparts. Electrochemical Impedance Spectroscopy (EIS) revealed initially high ionic resistance for the EPD-coated fibres, but a larger increase in resistance in the slurry coated electrodes over multiple cycles. This study demonstrated an innovative and novel method of analysing in greater detail, the cycling ability of the coated cathode material on carbon fibres using synchrotron radiation.
Author
Thomas Barthelay
University of Bath, Department of Mechanical Engineering
University of Oxford
Rob Gray
University of Bath, Department of Mechanical Engineering
Howard Richards
University of Bath, Department of Mechanical Engineering
Paloma Rodriguez Santana
University of Bath, Department of Mechanical Engineering
Sylvia Britto
STFC Rutherford Appleton Laboratory
Kalotina Geraki
Diamond Light Source
Zhenyuan Xia
Chalmers, Industrial and Materials Science, Materials and manufacture
Johanna Xu
Chalmers, Industrial and Materials Science, Material and Computational Mechanics
Leif Asp
Chalmers, Industrial and Materials Science, Material and Computational Mechanics
Chris R. Bowen
University of Bath, Department of Mechanical Engineering
Frank Marken
University of Bath, Department of Chemistry
Alexander J.G. Lunt
University of Bath, Department of Mechanical Engineering
Andrew T. Rhead
University of Bath, Department of Mechanical Engineering
Journal of Power Sources
0378-7753 (ISSN)
Vol. 630 236050Subject Categories (SSIF 2025)
Materials Chemistry
Other Chemical Engineering
DOI
10.1016/j.jpowsour.2024.236050