Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Effects of Flow Field and Diffusion Layer Properties on Water Accumulation in a PEM Fuel Cell

Published

Author(s)

Jon P. Owejan, T Trabold, D L. Jacobson, Muhammad D. Arif, S G. Kandlikar

Abstract

Water is the main product of the electrochemical reaction in a proton exchange membrane (PEM) fuel cell. Where the water is produced over the active area of the cell, and how it accumulates within the flow fields and gas diffusion layers, strongly affects the performance of the device and influences operational considerations such as freeze and durability. In this work, the neutron radiography method was used to obtain two-dimensional distributions of liquid water in operating 50 cm2 fuel cells. Variations were made of flow field channel and diffusion media properties, to assess the effects on the overall volume and spatial distribution of accumulated water. Flow field channels with hydrophobic coating retain more water, but the distribution of a greater number of smaller slugs in the channel area improves fuel cell performance at high current density. Channels with triangular geometry retain less water than rectangular channels of the same cross-sectional area, and the water is mostly trapped in the two corners adjacent to the diffusion media. Also, it was found that cells constructed using diffusion media with lower in-plane gas permeability tended to retain less water. In some cases, large differences in fuel cell performance were observed with very small changes in accumulated water volume, suggesting that flooding within the electrode layer or at the electrode-diffusion media interface is the primary cause of the significant mass transport voltage loss.
Citation
Journal of Power Sources

Keywords

fuel cell, hydrogen, neutron radiography, polymer electrolyte membrane, water management

Citation

Owejan, J. , Trabold, T. , Jacobson, D. , Arif, M. and Kandlikar, S. (2021), Effects of Flow Field and Diffusion Layer Properties on Water Accumulation in a PEM Fuel Cell, Journal of Power Sources (Accessed April 24, 2024)
Created October 12, 2021