Steady-state and EIS investigations of hydrogen electrodes and membranes in polymer electrolyte fuel cells: II. Experimental
2006 (English)In: Journal of the Electrochemical Society, ISSN 0013-4651, Vol. 153, no 4, A759-A764 p.Article in journal (Refereed) Published
Influence of water on membrane and anode performance was studied with steady-state and electrochemical impedance spectroscopy (EIS) measurements using a symmetrical cell with hydrogen on both sides. Both full-cell and half-cell measurements were performed. To obtain half-cell data a new reference electrode approach was demonstrated based on porous references in a four-electrode setup. A varying membrane resistance with current density was obtained using current interrupt and EIS measurements. The EIS measurements showed two semicircles at 10(4) Hz and 0.01-0.1 Hz, respectively. The first corresponds to hydrogen adsorption and the second to the water dependence of the electrode performance and membrane resistance. The low-frequency semicircle appears in a frequency range depending on the membrane thickness. The loop corresponding to the discharge of the double-layer capacitance through the Volmer reaction appears at frequencies too high to be experimentally measurable. The experimental data were in good agreement with the model developed in Part I of this paper. The model was also successfully fitted to experimental full cell data at different current densities and membrane thicknesses. The experiments confirmed that the low-frequency semicircle is attributed to the water dependence of both anode and membrane performance.
Place, publisher, year, edition, pages
2006. Vol. 153, no 4, A759-A764 p.
Current density, Electric currents, Electrodes, Frequencies, Fuel cells, Hydrogen, Polyelectrolytes, Porosity, Water
IdentifiersURN: urn:nbn:se:kth:diva-10084DOI: 10.1149/1.2172561ISI: 000235723600018ScopusID: 2-s2.0-33644790292OAI: oai:DiVA.org:kth-10084DiVA: diva2:207514
QC 201011042009-03-122009-03-112010-11-04Bibliographically approved