Variability and comparability of testing procedures for PEMFC stacks and modules regarding performance aspects

Reliable and reproducible testing protocols are needed for fuel cell stacks, modules and subsystems in order to reach comparable results for example in performance measurements. A testing protocol was developed which aims at the performance measurement of fuel cell stacks and modules. Measurements for the reproducibility and comparability were performed on a low temperature polymer electrolyte membrane fuel cell stack and on a fuel cell subsystem. The resulting voltages at the different load steps show a difference in adaption to load changes form the stack and the subsystem. In most cases the stack adapted faster with a more stable voltage. The repeatability of the testing protocols was tested which resulted in a higher degradation of the fuel cell subsystem compared to the stack. The measurements in comparison between two laboratories showed a clear decrease in voltages at the second laboratory. The measurement of the test protocol influences the fuel cell stack with an increase in voltage whereas the voltages decrease for the fuel cell subsystem.