Nondestructive testing of PEM fuel cells

We report on electric and magnetic nondestructive testing (NDT) of proton exchange membrane (PEM) fuel cells. Fuel cells are electrochemical devices that convert hydrogen and oxygen gas into water, heat and useable electricity. Fuel cell membrane health can affect the cells overall performance and lifetime. We have explored several NDT techniques employing highly sensitive HTS and LTS SQUID and fluxgate magnetometers. Magnetic fields generated by electrochemical currents flowing in the fuel cell are studied in the spatial, time and frequency domain under various operating conditions. Frequency domain electric and magnetic signals are compared under extreme conditions and membrane failure.