Mesoscopic Heat and Mass Transfer Process in Catalyst Layer of Proton Exchange Membrane Fuel Cells under Cold Environment

2025-01-7088

01/31/2025

Features
Event
SAE 2024 Vehicle Powertrain Diversification Technology Forum
Authors Abstract
Content
To explore the heat and mass transfer processes within the low-temperature catalyst layer, a coupled heat and mass transfer lattice Boltzmann model and electrochemical model were established, creating a pore-scale model for heat and mass transfer in the catalyst layer. The influence of the catalyst layer parameters was investigated. The results indicate that as time progresses, heat gradually accumulates at the top of the catalyst layer (CL) and is transmitted towards the bottom. Once oxygen enters the CL, it quickly fills the pores within the CL, resulting in a rapid decrease in oxygen concentration within the ionomer. As the platinum volume fraction increases, there is a significant rise in temperature across the entire calculation domain. With the increasing platinum volume fraction, the current density also increases rapidly due to the larger reaction area. When the carbon volume fraction is 0.15, more oxygen enters the ionomer to participate in reactions, and the large porosity enhances thermal convection, leading to the highest temperature at this point. As the ionomer content increases, the area of the high-temperature red zone within the CL also expands. However, with a carbon volume fraction of 0.25, the diffusion of oxygen in the pores is reduced, leading to most of the oxygen entering the ionomer, resulting in the highest current density among the three cases. Nonetheless, since thermal convection is stronger when the I/C weight ratios is relatively small, the overall temperature remains high. As the I/C weight ratios increases, oxygen diffusion weakens, and the overall current density shows an upward trend.
Meta TagsDetails
DOI
https://doi.org/10.4271/2025-01-7088
Pages
8
Citation
Xu, S., Chen, X., and Sheng, T., "Mesoscopic Heat and Mass Transfer Process in Catalyst Layer of Proton Exchange Membrane Fuel Cells under Cold Environment," SAE Technical Paper 2025-01-7088, 2025, https://doi.org/10.4271/2025-01-7088.
Additional Details
Publisher
Published
Jan 31
Product Code
2025-01-7088
Content Type
Technical Paper
Language
English