Raman spectroscopy for polymer electrolyte membrane fuel cell characterization

Abstract: This contribution shows how Raman spectroscopy can be used to characterize processes inside polymer electrolyte membrane (PEM) fuel cells. Two experimental setups have been designed for this purpose. In the first, a Raman microscope was constructed that allows hydrogen, oxygen, nitrogen, gaseous and liquid water to be detected. This device was used to detect changes in gas composition and water distribution induced by an artificial pinhole within the membrane electrolyte assembly (MEA). In the second setup, a multiple-fiber Raman spectrometer was developed to refine in situ fuel cell investigation. This setup allows gas composition, liquid water and water vapor to be recorded simultaneously and also reveals how these substances change locally during fuel cell operation.