Volume 50

Effect on the binder morphology on stochastic reconstruction of gas diffusion layer in PEMFC Kai Lu, Rui Lin

Abstract

The gas diffusion layer is one of the most important components of the proton exchange membrane fuel cell (PEMFC). Microstructure reconstruction is an efficient research strategy. The influence of the morphological presence of resin binder when applying a stochastic method to reconstruct the three-dimensional gas diffusion layer was studied. Finite element method (FEM) simulation was conducted to explore the mechanical response under compression load for both reconstruction models with the binder morphologically present or absent. The differences in pore structure of the two reconstructed models before and after compression were meticulously analyzed. The morphological appending of the binder made the overall equivalent modulus larger, but the deformation and stress concentration became severe. When subjected to a compression ratio of 20%, the porosity changed to 74.4% and 74.7% for structures with and without the presence of binder morphology, respectively. Binder morphological addition altered the pore space greatly, making it a more uniform pore size distribution and a smoother porosity variation. In the through-plane (TP) direction, the morphological presence of the binder decreased the tortuosity, while in the in-plane (IP) direction, the tortuosity increased.

Keywords PEMFC, gas diffusion layer, binder morphology, mechanical behavior, pore structure