Investigating the water and thermal distributions within the anomalous PEMFC based on a 1D two-phase multi-physics model

Abstract

At present, a small number of studies aim at the influence of degraded components on the distribution characteristics in water-cooled proton exchange membrane fuel cells (PEMFCs). This study develops a one-dimensional (1D) two-phase multi-physics model for a water-cooled PEMFC and investigates the parameter distributions along the through-plane direction. The model is accomplished by self-written codes and validated by the experimental data. Two dimensionless indices (TUI, WUI) are defined to present the distribution uniformity in membrane electrode assembly (MEA). The current intensity and gaseous relative humidity (RH) are the primary factors affecting MEA temperature and membrane water. However, with the anode RH increasing from 0.2 to 1.0, the WUI value decreases from 0.123 to 0.104 despite the water content increasing from 8.9 to 14.4. The results through comparison indicate that, in case 2, severe degradation in porosity, hydrophobicity, and thickness of component materials leads to a high liquid saturation of 0.82 on CCL, which increases the hence of water flooding. In return, the water flooding further reduces voltage performance by 0.1 V compared with the normal cell, even accelerating the component degradation.