Acoustic Emission Analysis of Polymer Electrolyte Membrane Fuel Cells

The performance of a polymer electrolyte membrane fuel cell (PEMFC) is characterized using acoustic emission (AE) based analysis. Polarization scans indicate that an increase in cell temperature from 45°C to 60°C results in a drop in maximum current density due to cell dehydration. Parametric analysis of acoustic activity generated from the PEMFC during polarization establishes a relationship between the cell operating conditions and the corresponding AE generated. Optimal and dehydrated cell conditions result in stable and reduced numbers of generated acoustic events, respectively, which are related to the flow of water and its physical state in the flow-fields. Furthermore, the AE parameters utilized for hydration analysis are amplitude and counts, which correspond to intensity and proportion of AE generated beyond a threshold, respectively; these are influenced by current density, reactant humidity, and cell temperature.