Electrode and catalyst durability requirements in automotive PEM applications: Technology status of a recent MEA design and next generation challenges

You are here: Homepage > Search

Electrode and catalyst durability requirements in automotive PEM applications: Technology status of a recent MEA design and next generation challenges

Haas, H.R. / Davis, M.T.

Key durability requirements for automotive PEM (proton exchange membrane) catalyst layers include voltage cycling, air-air starts and freeze starts. Multiple system and cell design approaches may cascade additional stressors for the catalysts and electrodes. Occurrences of low cathode potentials, non-uniform fuel distribution and high anode potentials must be expected and accounted for by MEA (membrane electrode assembly) design. The experimental results shown in the first section of this paper functionally demonstrate PEM automotive MEA technology capability. Drive cycle durability results of 2000 hours, 7000 cycles in an air-air start stress test as well as 500 freeze starts were demonstrated with one MEA design, with manageable performance loss. Similar MEA designs enable vehicle operation of approximately 100000 km. Technical results in the second section present some of the material-based challenges on the path towards cost reduction. The investigated Pt/Co alloy catalysts - desired for their high performance - show excessive degradation in automotive drive cycle tests. Pt/Co alloy stability found only in a small voltage window between 0.6 V - 0.9 V confirms that current alloys lack stability for use in a realistic system approach. Pt based catalysts with cathode loadings of 0.4 mg/cm2 and less show high degradation in air-air start stress tests. Reduced Pt loadings were found to be more susceptible to expected failure modes of carbon corrosion and Pt area loss. These results present a significant challenge for next generation automotive designs where cost reduction will be a key driver.

Access

Access via TIB

Check availability in my library

Order at Subito €

Export, share and cite

Document information

Title :

Electrode and catalyst durability requirements in automotive PEM applications: Technology status of a recent MEA design and next generation challenges

Contributors:

Haas, H.R. (author) / Davis, M.T. (author)

Published in:

ECS Meeting, Meeting of the Electrochemical Society, 216, Symposium B8, PEMFC, International Symposium on Proton Exchange Membrane Fuel Cells, 9 ; 1623-1631

ECS Transactions ; 25 , 1,2

Publication date :

2009

Size :

9 Seiten, 7 Bilder, 1 Tabelle, 9 Quellen

ISBN :

978-1-56677-738-4

DOI :