PEM fuel cells (IMAGE) University of Seville Caption yz− weighted average of current density (a), temperature (b), and water content (d) across the membrane. Averaged water saturation (c) is reported in between GDLs and membrane. Subplot (e) describes the oxygen concentration average in the GDLc/channel/rib interface. Shaded areas represent half-rib zones. Operating temperature is T0 = 343 K and reactants relative humidity is 90%. Credit Universidad de Sevilla Usage Restrictions No restrictions. License Public Domain Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.