Numerical modeling of the mechanical behavior of proton exchange membrane fuel cell performance: Design of experiment study and optimization

The fundamental magnitude which can be associated with the performance of a fuel cell is the contact pressure. The contact pressure sustained by the GDL will directly impact the electrical performance of the fuel cell, in particular the contact resistance. This contact resistance can be modeled in two different ways: analytically from the mechanical model and electrically from a mechanical - electrical coupling model. We opted for the analytical resolution. The contact resistance was calculated analytically, based on the mechanical model. Note that the contact resistance is influenced by several mechanical parameters such as the clamping pressure, the porosity of the GDL and the dimensions of two components GDL and BPP. This porosity decreases during compression in order to make waterproofing. In our study, to model the porosity of the GDL, two approaches were presented: pore network approach (used in the case of low porosity) and continuous approach (used in the case of high porosity). It is necessary to quantify and verify the influence of three factors: the porosity of the GDL, the bending radius of the bipolar plate and the thickness of the GDL on the contact pressures. To do this, we conducted two experimental plans on the stack: one corresponding to low porosity and the other one to high porosity. The optimal parameters having been identified, we found a good correlation between the numerical results and the experimental results found in the bibliography. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.