Correlation of Changes in Electrochemical and Structural Parameters due to Voltage Cycling Induced Degradation in PEM Fuel Cells. Issue 6 (1st January 2018)

• Record Type: Journal Article
• Authors: Kneer, Alexander; Jankovic, Jasna; Susac, Darija; Putz, Andreas; Wagner, Nadja; Sabharwal, Mayank; Secanell, Marc
• Is Part Of: Journal of the Electrochemical Society. Volume 165:Issue 6(2018)
• Page Start: F3241
• Page End: F3250
• Publication Date: 2018-01-01
• Subjects: Catalyst degradation -- Oxygen transport resistance -- Transmission electron microscopy; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0271806jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : Membrane electrode assemblies were degraded by voltage cycling in hydrogen/air atmosphere. The impact of degradation on fuel cell performance was measured by various electrochemical characterization techniques. Loss of electrochemically active surface area was correlated to kinetic voltage losses at low current density as well as losses at high current density due to oxygen transport limitations. It was found that the oxygen transport resistance scales proportionally to the inverse of normalized platinum surface area. The change in the catalyst layer structural properties due to voltage cycling was visualized by electron microscopy. A new method of calculating changes in platinum loading of degraded samples by transmission electron microscopy is presented and shows redistribution of platinum in the catalyst layer due to platinum dissolution.