Date of Award
2026
Document Type
Campus Access Dissertation
Degree Name
Doctor of Philosophy in Mechanical Engineering-Engineering Mechanics (PhD)
Administrative Home Department
Department of Mechanical and Aerospace Engineering
Advisor 1
Jeffrey S. Allen
Committee Member 1
Youngchul Ra
Committee Member 2
Kazuya Tajiri
Committee Member 3
Marc Secanell
Abstract
A comprehensive computational model is proposed that resolves the microstructural heterogeneity inside PEMFC catalyst layers and predicts the interplay between local transport processes and overall cell performance. Three connected networks representing the ionomer, pore, and carbon phases are constructed from macroscopic catalyst layer properties. Each network consists of cylindrical elements representing transport resistance with volumeless nodes where local potentials are stored. Microstructural heterogeneity is introduced through spatially varying factors influencing local transport resistance while macroscopic structural properties are conserved. A key contribution is the ionomer phase is described by a poroelastic swelling model adapted for thin confined films, which determines how each elementof the ionomer network absorbs water and swells under local humidity and temperature conditions. Swelling reshapes the neighboring pore space and redistributes transport resistances across the electrode. Governing transport equations are applied to the coupled networks, providing local water balance, oxygen concentration, proton current, temperature distribution, and liquid saturation at each point in the catalyst layer. The network reveals these local quantities are intricately connected, how their spatial variation arises from the underlying microstructure, and how these nonlinearities ultimately govern the measurable performance of the fuel cell. The pore-network formulation is computationally efficient, enabling parametric studies and full polarization curve generation within practical turnaround times. The modeling approach is adaptable to catalyst layers of different chemistry and morphology without case-specific fitting. The proposed tool is intended to serve as a premanufacturing guideline for electrode design and a post-manufacturing testing tool for evaluating catalyst layer performance.
Recommended Citation
Alam, Shahriar, "Microstructure-Resolved Network Model For PEMFC Electrodes", Campus Access Dissertation, Michigan Technological University, 2026.