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Title: Effects of cell-to-cell fuel mal-distribution on fuel cell performance and a means to reduce mal-distribution using MEMS micro-valves

Abstract

Achieving uniform flow among the cells of a fuel cell stack plays a significant role in being able to operate at maximum capability and efficiency. This paper presents experimental data showing the importance of cell-to-cell fuel flow balancing on fuel cell performance, and a fuel cell energy management (FCEM) technique that has demonstrated the ability to improve stack performance. In a specially instrumented four-cell polymer electrolyte fuel cell that allows external control of the air, fuel, and water-cooling flows to each cell, fuel to a single cell was reduced. V–I curves collected under these unbalanced conditions are compared to curves collected when the fuel flow to each cell was balanced. Reducing the fuel flow to a single cell by 11% decreased the V–I curve cutoff load by 10%—demonstrating the degree of negative effect that unbalanced fuel flows can have on stack performance. Typical fuel cell stacks have no dynamic means to keep flows in the stack balanced between the cells, but through the use of custom-built, piezoelectric micro-valves, a simple flow control strategy, and this custom four-cell laboratory stack, the positive effects of FCEM flow balancing at three different fuel flow rates was demonstrated.

Authors:
; ; ;  [1];  [1];  [1]
  1. (Univ. of Pittsburgh, Pittsburgh, PA)
Publication Date:
Research Org.:
National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV
Sponsoring Org.:
USDOE - Office of Fossil Energy (FE)
OSTI Identifier:
912836
Report Number(s):
DOE/NETL-IR-2007-066
Journal ID: ISSN 0378-7753; TRN: US200802%%404
DOE Contract Number:
None cited
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Power Sources; Journal Volume: 164; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
30 DIRECT ENERGY CONVERSION; EFFICIENCY; ENERGY MANAGEMENT; FLOW RATE; FUEL CELLS; PERFORMANCE; PROTON EXCHANGE MEMBRANE FUEL CELLS; PEMFC; MEMS; Micro-valve; Fuel cell energy management; Flow imbalance

Citation Formats

Hensel, J.P., Gemmen, R.S., Thornton, J.D., Vipperman, J.S., Clark, W.W., and Bucci, B.A. Effects of cell-to-cell fuel mal-distribution on fuel cell performance and a means to reduce mal-distribution using MEMS micro-valves. United States: N. p., 2007. Web. doi:10.1016/j.jpowsour.2006.09.049.
Hensel, J.P., Gemmen, R.S., Thornton, J.D., Vipperman, J.S., Clark, W.W., & Bucci, B.A. Effects of cell-to-cell fuel mal-distribution on fuel cell performance and a means to reduce mal-distribution using MEMS micro-valves. United States. doi:10.1016/j.jpowsour.2006.09.049.
Hensel, J.P., Gemmen, R.S., Thornton, J.D., Vipperman, J.S., Clark, W.W., and Bucci, B.A. Wed . "Effects of cell-to-cell fuel mal-distribution on fuel cell performance and a means to reduce mal-distribution using MEMS micro-valves". United States. doi:10.1016/j.jpowsour.2006.09.049.
@article{osti_912836,
title = {Effects of cell-to-cell fuel mal-distribution on fuel cell performance and a means to reduce mal-distribution using MEMS micro-valves},
author = {Hensel, J.P. and Gemmen, R.S. and Thornton, J.D. and Vipperman, J.S. and Clark, W.W. and Bucci, B.A.},
abstractNote = {Achieving uniform flow among the cells of a fuel cell stack plays a significant role in being able to operate at maximum capability and efficiency. This paper presents experimental data showing the importance of cell-to-cell fuel flow balancing on fuel cell performance, and a fuel cell energy management (FCEM) technique that has demonstrated the ability to improve stack performance. In a specially instrumented four-cell polymer electrolyte fuel cell that allows external control of the air, fuel, and water-cooling flows to each cell, fuel to a single cell was reduced. V–I curves collected under these unbalanced conditions are compared to curves collected when the fuel flow to each cell was balanced. Reducing the fuel flow to a single cell by 11% decreased the V–I curve cutoff load by 10%—demonstrating the degree of negative effect that unbalanced fuel flows can have on stack performance. Typical fuel cell stacks have no dynamic means to keep flows in the stack balanced between the cells, but through the use of custom-built, piezoelectric micro-valves, a simple flow control strategy, and this custom four-cell laboratory stack, the positive effects of FCEM flow balancing at three different fuel flow rates was demonstrated.},
doi = {10.1016/j.jpowsour.2006.09.049},
journal = {Journal of Power Sources},
number = 1,
volume = 164,
place = {United States},
year = {Wed Jan 10 00:00:00 EST 2007},
month = {Wed Jan 10 00:00:00 EST 2007}
}
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