Measurement of protonic resistance of catalyst layers as a tool for degradation monitoring

Thomas Gaumont (1) , G. Maranzana (1) , Olivier Lottin (1) , Jérôme Dillet (1) , Sophie Didierjean (1) , J Pauchet (2) , L Guétaz (2)

1 LEMTA - Laboratoire d'Energétique et Mécanique Théorique et Appliquée
2 CEA - Commissariat à l'énergie atomique et aux énergies alternatives

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 H 2 /N 2 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 trough plane and in plane heterogeneities. Then, results of the degradation of a MEA submitted to four different accelerated stress tests are presented. They consist of (i) a constant current operation, (ii) 1.2V 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 microstrucure during AST.

Mots clés: Electrochemical Impedance Spectroscopy; catalyst layer ionic resistance; protonic resistance; PEMFC electrode degradation; ionomer degradation; carbon corrosion

Domaines: Génie des procédés; Milieux fluides et réactifs; Autre; Polymères; Génie chimique; Catalyse

Thomas Gaumont, G. Maranzana, Olivier Lottin, Jérôme Dillet, Sophie Didierjean, et al.. Measurement of protonic resistance of catalyst layers as a tool for degradation monitoring. International Journal of Hydrogen Energy, 2017, 42 (3), pp.1800-1812. ⟨10.1016/j.ijhydene.2016.10.035⟩. ⟨hal-01744069⟩