In Situ Measurements of Membrane-Electrode-Assemblies (MEA) with Different Electrode Compositions

摘要

In order to investigate electrodes for fuel cells, it is advantageous to characterise ME As in operation. Besides in situ characterisation methods like V-i-curve measurement and electrochemical impedance spectroscopy, half cell tests as well as cyclic voltametry are useful tools to get more information about MEAs. Usually, these tests are conducted with different samples in separate test units, which means a higher complexity for the sample preparation and thus, a higher failure range. The development of a special cell holder allows to apply all the above mentioned characterisation methods for the same test sample consecutively without interrupting, disconnecting and reassembling the cell. The cell holder divides the cell into two separate measuring fields. Both parts are supplied with the reaction gases. One part is operated under load with hydrogen and air, the other one is under open circuit voltage with hydrogen and oxygen as reactants. The parts are only connected by the electrolyte membrane.