Measurement of protonic resistance of catalyst layers as a tool for degradation monitoring. (19th January 2017)

• Record Type: Journal Article
• Authors: Gaumont, T.; Maranzana, G.; Lottin, O.; Dillet, J.; Didierjean, S.; Pauchet, J.; Guétaz, L.
• Is Part Of: International journal of hydrogen energy. Volume 42:Number 3(2017)
• Page Start: 1800
• Page End: 1812
• Publication Date: 2017-01-19
• Subjects: Electrochemical impedance spectroscopy -- Catalyst layer ionic resistance -- Protonic resistance -- PEMFC electrode degradation -- Ionomer degradation -- Carbon corrosion; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2016.10.035
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: The ionic resistance of a PEM fuel cell catalyst layer, as well as the double layer capacity and the high frequency resistance are estimated from the impedance spectra of H2 /N2 operated cell, thanks to a volumetric electrode model. The impedance spectra are calculated in the case of a homogeneous distribution of resistivity and capacity, and considering both through plane and in plane heterogeneities. Then, results of the degradation of a MEA subjected to four different accelerated stress tests are presented. They consist of (i) a constant current operation, (ii) 1.2 V potential hold with nitrogen and hydrogen (iii) open circuit voltage (OCV) hold with air and hydrogen, and (iv) a start-up protocol where heterogeneous degradations are observed using a linear segmented fuel cell. This technique can provide useful information about the evolution of catalyst layer microstructure during AST. Highlights: An impedance method for measuring the protonic resistance of a PEMFC catalyst layers. Impedance parameters monitoring during accelerated stress tests. Catalyst layer ionomer preserved from severe degradation. Electrode degradation due to carbon reversible and irreversible oxidation.