Morphology studies on high-temperature polymer electrolyte membrane fuel cell electrodes

Mack F, Klages M, Scholta J, Jörissen L, Morawietz T, Hiesgen R, Kramer D, Zeis R (2014)

Publication Type: Journal article

Publication year: 2014

Journal

Journal of Power Sources Elsevier

Book Volume: 255

Pages Range: 431-438

DOI: 10.1016/j.jpowsour.2014.01.032

Abstract

The electrode morphology influences the properties and performance of polymer electrolyte membrane fuel cells (PEMFC). Here we report our studies of two different electrodes for high-temperature PEMFC prepared by spraying and coating and their impact on the fuel cell performance. Differences in 3D microstructure and adhesion between catalyst layer and gas diffusion layer (GDL) of the electrodes were studied with X-ray microtomography. Scanning electrode microscope investigations show hairline cracks between agglomerates on the surface of the sprayed electrode, whereas the coated electrode shows a network of shrinkage cracks in the catalyst layer. The distribution of the electrode binder polytetrafluoroethylene (PTFE) is related to the locally resolved conductivity, which was determined by scanning the electrode surfaces with a conductive atomic force microscopy (AFM) tip. The macrostructures of the sprayed and coated electrodes are different but contain similar pore structures. The coated electrode has a higher PTFE concentration on the top region, which tends to form a nonconductive and less wettable "skin" on the electrode surface and delays the start-up of the fuel cell. In contrast to low-temperature PEMFC, the electrode morphology has only a minor impact on the steady-state cell performance of high-temperature PEMFC. © 2014 Elsevier B.V. All rights reserved.

Authors with CRIS profile

Roswitha Zeis

Involved external institutions

Helmholtz Institut Ulm DE Germany (DE) Zentrum für Sonnenenergie- und Wasserstoff-Forschung (ZSW) DE Germany (DE) Hochschule Esslingen University of Applied Sciences DE Germany (DE)

How to cite

APA:

Mack, F., Klages, M., Scholta, J., Jörissen, L., Morawietz, T., Hiesgen, R.,... Zeis, R. (2014). Morphology studies on high-temperature polymer electrolyte membrane fuel cell electrodes. Journal of Power Sources, 255, 431-438. https://doi.org/10.1016/j.jpowsour.2014.01.032

MLA:

Mack, Florian, et al. "Morphology studies on high-temperature polymer electrolyte membrane fuel cell electrodes." Journal of Power Sources 255 (2014): 431-438.

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