Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7709255 | International Journal of Hydrogen Energy | 2017 | 12 Pages |
Abstract
In this study, the impacts of relative humidity on liquid water accumulation and mass transport resistance at high current densities were investigated for polymer electrolyte membrane (PEM) fuel cell cathode gas diffusion layers (GDLs). Through-plane liquid water saturation distributions were measured in situ using synchrotron X-ray radiography while simultaneously performing limiting current-based characterizations of oxygen transport resistance. In experiments with inlet cathode reactant relative humidity ranging from 0% to 100%, high local saturations (>0.6) were consistently observed in the GDL region adjacent to the flow field lands when the fuel cell reached limiting current. High land-region saturation is a possible indication of lower local temperatures. In the carbon fiber substrate portion of the GDL (i.e. excluding the MPL), the liquid water volume in the regions adjacent to the flow field channels was consistently small relative to the water volume adjacent to the land regions. We observed a trend of increasing liquid water saturation of the GDL adjacent to the channels with increasing levels of cathode inlet relative humidity, along with corresponding small increases in total oxygen transport resistance.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Daniel Muirhead, Rupak Banerjee, Jongmin Lee, Michael G. George, Nan Ge, Hang Liu, Stéphane Chevalier, James Hinebaugh, Kookil Han, Aimy Bazylak,