In this review, an overview of cracks and interfacial voids formed in membrane electrode assemblies in polymer electrolyte fuel cells is presented. State-of-the-art of findings on formation processes of the cracks and the voids are described together with recent advances on development of characterization and diagnostic tools. The drawbacks and potentials of the cracks and the interfacial voids in the MEAs are also discussed. The cracks and the voids possibly deteriorate cell performance due to less electrical contact in the MEAs. On the other hand, the cracks can enhance the liquid and the gas transport in the MEAs that is better for PEFCs. Finally, future perspectives and remaining challenges concerned with the cracks and the interfacial voids are addressed.
2015 by The Japan Society of Mechanical Engineers and The Heat Transfer Society of Japan