Numerical investigation of effect of mechanical compression on the transport properties of fuel cell microporous layer using a pore-scale model
Date
2024
Authors
Zhang, Heng
Hu, Hao
Sarker, Mrittunjoy
Shao, Xuanyu
Zhan, Zhigang
Sui, Pang-Chieh
Chuang, Po-Ya Abel
Journal Title
Journal ISSN
Volume Title
Publisher
International Journal of Hydrogen Energy
Abstract
The microporous layer (MPL) plays an important role in water and thermal management of proton exchange membrane fuel cells (PEMFCs). An in-depth investigation of the mechanical compression effect on transport properties in the MPL can help optimize cell performance. In this work, the microstructure of the MPL is numerically reconstructed and the finite element method is applied to simulate mechanical behavior. Besides, the distribution of stress-strain, porosity, and pore size in the MPL under ten different levels of mechanical compression strains are studied. Lastly, the pore-scale model is employed to investigate the effective transport properties of the MPL as a function of compression strain. The analysis reveals that as the MPL strain increases from 0% to 40%, there is a 29% decrease in porosity, a 50% reduction in average pore diameter, a 60% decrease in effective gas diffusivity, a 100% increase in tortuosity, and an 80% increase in electrical and thermal conductivity. With the escalation of mechanical compression, both the magnitude and uniformity of stress-strain-displacement concurrently rise. Mechanical compression strains below 20% exhibit a lesser impact on transport properties. Beyond this threshold, exceeding the 20% compression strain point, mechanical stress assumes a critical role in influencing MPL transport properties.
Description
Keywords
PEMFC, MPL, stress and strain, mechanical compression, transport properties, pore scale model, Institute for Integrated Energy Systems (IESVic)
Citation
Zhang, H., Hu, H., Sarker, M., Shao, X., Zhan, Z., Sui, P-C., & Chuang, P-Y A. (2024). Numerical investigation of effect of mechanical compression on the transport properties of fuel cell microporous layer using a pore-scale model. International Journal of Hydrogen Energy, 62, 591-600. https://doi.org/10.1016/j.ijhydene.2024.03.102