Work

Pore-Water Morphological Transitions in Polymer Electrolyte of a Fuel Cell

Year: 2009

Type: article

Abstract: We show a criticality of three water morphological transitions on pore-water transport and proton conductivity in Nafion of a polymer electrolyte membrane fuel cell, addressing its pore-size distribution and the Schröder paradox.The first transition leads to the onset of proton conductivity; the second allows for the onset of the capillary percolation channels and proton conductivity jump at a low water content im,H 2 O = 5.Using this as immobile saturation, the predicted water distribution and cell performance are in reasonable agreement with the available experiments.The third ͑the paradox, postulating further capillary advancing͒ bounds the maximum water content on the cathode side of Nafion, which is also supported by the proposed adsorption isobar ͑thermodynamic equilibrium limit͒.These transitions appear in the available pore-size experiments which show capillary percolation channel sizes.In addition, the optimal Nafion pore-water content is between the second and third transitions.

Source: Journal of The Electrochemical Society

DOI: 10.1149/1.3186027

Authors: G. S. Hwang, M. Kaviany, J. H. Nam, M. H. Kim, S. Y. Son

Institutions: University of Michigan, Kookmin University, Pohang University of Science and Technology, University of Cincinnati

Language: English

Topic: Fuel Cells and Related Materials

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: bronze

Funder: University of Michigan