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Title: Investigating fuel-cell transport limitations using hydrogen limiting current

Abstract

Reducing mass-transport losses in polymer-electrolyte fuel cells (PEFCs) is essential to increase their power density and reduce overall stack cost. At the same time, cost also motivates the reduction in expensive precious-metal catalysts, which results in higher local transport losses in the catalyst layers. Here, we use a hydrogen-pump limiting-current setup to explore the gas-phase transport losses through PEFC catalyst layers and various gas-diffusion and microporous layers. It is shown that the effective diffusivity in the gas-diffusion layers is a strong function of liquid saturation. Additionally, it is shown how the catalyst layer unexpectedly contributes significantly to the overall measured transport resistance. This is especially true for low catalyst loadings. It is also shown how the various losses can be separated into different mechanisms including diffusional processes and mass-dependent and independent ones, where the data suggests that a large part of the transport resistance in catalyst layers cannot be attributed to a gas-phase diffusional process. The technique is promising for deconvoluting transport losses in PEFCs.

Authors:
 [1];  [1];  [1];  [1]; ORCiD logo [1]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Technologies Area
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Fuel Cell Technologies Office (EE-3F)
OSTI Identifier:
1379846
Alternate Identifier(s):
OSTI ID: 1396501
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
International Journal of Hydrogen Energy
Additional Journal Information:
Journal Volume: 42; Journal Issue: 19; Journal ID: ISSN 0360-3199
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
08 HYDROGEN; 30 DIRECT ENERGY CONVERSION; limiting current; resistance; catalyst layer; effective diffusivity; gas-diffusion layer; low loading

Citation Formats

Spingler, Franz B., Phillips, Adam, Schuler, Tobias, Tucker, Michael C., and Weber, Adam Z.. Investigating fuel-cell transport limitations using hydrogen limiting current. United States: N. p., 2017. Web. doi:10.1016/j.ijhydene.2017.01.036.
Spingler, Franz B., Phillips, Adam, Schuler, Tobias, Tucker, Michael C., & Weber, Adam Z.. Investigating fuel-cell transport limitations using hydrogen limiting current. United States. doi:10.1016/j.ijhydene.2017.01.036.
Spingler, Franz B., Phillips, Adam, Schuler, Tobias, Tucker, Michael C., and Weber, Adam Z.. Thu . "Investigating fuel-cell transport limitations using hydrogen limiting current". United States. doi:10.1016/j.ijhydene.2017.01.036. https://www.osti.gov/servlets/purl/1379846.
@article{osti_1379846,
title = {Investigating fuel-cell transport limitations using hydrogen limiting current},
author = {Spingler, Franz B. and Phillips, Adam and Schuler, Tobias and Tucker, Michael C. and Weber, Adam Z.},
abstractNote = {Reducing mass-transport losses in polymer-electrolyte fuel cells (PEFCs) is essential to increase their power density and reduce overall stack cost. At the same time, cost also motivates the reduction in expensive precious-metal catalysts, which results in higher local transport losses in the catalyst layers. Here, we use a hydrogen-pump limiting-current setup to explore the gas-phase transport losses through PEFC catalyst layers and various gas-diffusion and microporous layers. It is shown that the effective diffusivity in the gas-diffusion layers is a strong function of liquid saturation. Additionally, it is shown how the catalyst layer unexpectedly contributes significantly to the overall measured transport resistance. This is especially true for low catalyst loadings. It is also shown how the various losses can be separated into different mechanisms including diffusional processes and mass-dependent and independent ones, where the data suggests that a large part of the transport resistance in catalyst layers cannot be attributed to a gas-phase diffusional process. The technique is promising for deconvoluting transport losses in PEFCs.},
doi = {10.1016/j.ijhydene.2017.01.036},
journal = {International Journal of Hydrogen Energy},
number = 19,
volume = 42,
place = {United States},
year = {Thu Mar 09 00:00:00 EST 2017},
month = {Thu Mar 09 00:00:00 EST 2017}
}

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