Effect of cross-flow on PEFC liquid-water distribution: An in-situ high-resolution neutron radiography study

Effect of cross-flow on PEFC liquid-water distribution: An in-situ high-resolution neutron radiography study

TitleEffect of cross-flow on PEFC liquid-water distribution: An in-situ high-resolution neutron radiography study
Publication TypeJournal Article
Year of Publication2015
AuthorsSantamaria, Anthony D., Maxwell K. Becton, Nathanial J. Cooper, Adam Z. Weber, and Jae Wan Park
JournalJournal of Power Sources
Volume293
Pagination162 - 169
Date Published10/2015
ISSN03787753
Abstract

Liquid-water management in polymer-electrolyte fuel cells (PEFCs) remains an area of ongoing research. To enhance water removal, certain flow-fields induce cross-flow, or flow through the gas-diffusion layer (GDL) via channel-to-channel pressure differences. While beneficial to water removal, cross-flow comes at the cost of higher pumping pressures and may lead to membrane dehydration and other deleterious issues. This paper examines the impact of cross-flow on component saturation levels as determined through in-plane high-resolution neutron radiography. Various humidities and operating conditions are examined, and the results demonstrate that cell saturation levels correlate strongly with the level of cross-flow rate, and lower GDL saturation levels are found to correlate with an increase in permeability at higher flow rates. Effective water removal is found to occur at channel-to-channel pressure gradients greater than the measured breakthrough pressure of the GDL, evidence that similar liquid-water transport mechanisms exist for under-land area transport as in transverse GDL flow.

DOI10.1016/j.jpowsour.2015.05.016