PEM fuel cell systems are operated on the hydrogen side with "anode recirculation" or in "dead end" mode. In both operating modes, areas with an insufficient hydrogen supply can easily form on the anode side, initially unnoticed. At these points, a strong increase in the local electrochemical potential causes, among other things, strong degradation of the catalyst layers and thus premature failure of the fuel cell system.
In order to counteract or alleviate this problem, ZBT is developing dynamic reference electrodes (DHE) with a very low height in cooperation with the Hahn-Schickard-Gesellschaft (HSG-VS), that can be integrated into the membrane electrode assembly (MEA). And a compact multi-sensor unit is being developed that can determine pressure, temperature, flow rate and the partial pressures of N2 and O2 on the anode side.
The combination of these two devices will make it possible to clearly identify critical operating conditions and their causes at an early stage. Both the MEAs equipped with the reference electrodes and the sensor units are designed in such a way that they can be integrated into common fuel cell systems.
The aim is to significantly increase the service life and efficiency of the fuel cell systems compared to the current state of the art by means of system control based on these measured values, e.g. by "purging" (flushing) the anode side as required.
Project title: SAFEREF Development of reference electrodes suitable for mass production coupled with microgas measurement technology to ensure the safe operation of PEM fuel cell systems.
Project timeframe: 1 Apr 2020 – 30 Sep2022
Contacts:
- Hahn-Schickard-Gesellschaft für angewandte Forschung e.V. (HSG-VS)
Department: Thermal Sensors
Dr. Sophie Billat, Sophie.Billat(at)hahn-schickard.de - Zentrum für BrennstoffzellenTechnik (ZBT) GmbH
Department: Electrochemical Components
Dr. Burghard Lutter, b.lutter(at)zbt.de
Funded via the AiF member association IUTA