Quantification analysis of membrane buckling into gas diffusion layer holes and its consequences for fuel cell membrane durability

Fuel cell membrane deformation and durability can be affected by holes at the surface of the gas diffusion layers (GDLs). To improve quality control for fuel cell manufacturing, it is important to understand the severity level of the holes, so that subsequent mitigation measures can be taken. In this work, the impact of GDL holes on membrane deformation is investigated using X-ray computed tomography as the primary investigative tool combined with a computationally inexpensive finite element model that utilizes spring foundation to simulate the compressive load of the GDL. Based on consistent experimental and simulation results, the critical threshold GDL hole diameter that is capable of inducing membrane buckling related failure is 100 ± 10 μm under the flow channel, below which the influence of GDL holes on membrane deformation is insignificant. However, GDL holes of any size can cause membrane buckling under the land due to locally elevated through-plane compression. As a mitigation strategy, membrane buckling can be suppressed by reducing the membrane thickness. Thinner membranes can effectively reduce water uptake during relative humidity cycles, thus reducing membrane deformation induced by cyclic expansion and shrinkage. • Combined visualization and modeling analysis of membrane buckling deformation. • Under channels: a threshold hole dimension is required to trigger membrane buckling. • Under lands: any gas diffusion layer hole dimensions trigger membrane buckling. • A strong impact of in-plane friction on buckling onset and progression is revealed. • Thinner membranes shown to effectively reduce buckling and stress concentration.