Abstract #1333, 224th ECS Meeting, © 2013 The Electrochemical Society
Effect of Cationic Contaminants on Polymer
Electrolyte Fuel Cell Performance
Cathode Out
Anode in
a,b
Jing Qi , Xiaofeng Wang , Mehmet Ozan Ozdemir ,
Md Aman Uddina,b, Leonard Bonvilleb,
Ugur Pasaogullari*,a,b, and Trent Molterb,c
Test Station
Fuel Cell
Cathode in
Air
a
Department of Mechanical Engineering, bCenter for
Clean Energy Engineering, and cDepartment of Material
Science & Engineering,
University of Connecticut, 44 Weaver Rd. U-5233, Storrs,
CT 06269
Back Pressure
Regulator
Nebulizer
Air
Pump
Cation Solution
0.8
Contaminant injection start
DI Water
0.7
0.6
Voltage (V)
Back to DI water
0.5
0.4
0.3
Ba(ClO4)2
Ca(ClO4)2
Al(ClO4)3
KClO4
0.2
0.1
0
0
10 20 30 40 50 60 70 80 90 100 110 120 130
Time (h)
600
500
400
300
Cell Voltage (V)
200
Voltage (Before Durability Test)
Voltage (After Durability Test)
Power (Before Durability Test)
Power (After Durability Test)
0
100
0
200 400 600 800 1000 21200 1400
Current Density (mA/cm )
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
600
Ca(ClO4)2
500
400
300
200
Voltage (Before Durability Test)
Voltage (After Durability Test)
Power (Before Durability Test)
Power (After Durability Test)
0
200
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
100
0
400 600 800 1000 1200 1400
Current Density (mA/cm2)
700
Al(ClO4)3
600
500
400
300
Voltage (Before Durability Test)
Voltage (After Durability Test)
Power (Before Durability Test)
Power (After Durability Test)
0
Cell Voltage (V)
700
Ba(ClO4)2
Power Density (mW/cm2)
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
200
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
200
100
0
400 600 800 1000 1200 1400
Current Density (mA/cm2)
700
KClO4
600
500
400
300
Voltage (Before Durability Test)
Voltage (After Durability Test)
Power (Before Durability Test)
Power (After Durability Test)
200
Power Density (mW/cm2)
Cell Voltage (V)
Figure 2. Cell voltage and resistance during constant
current hold (1 A/cm2).
0
200
100
0
400 600 800 1000 1200 1400
Current Density (mA/cm2)
Figure 3. PEFC performance
contaminant injection.
* Corresponding author. E-mail:[email protected]
1400
1300
1200
1100
1000
900
800
700
600
500
400
300
200
100
0
Back to DI Water
Resistance (mΩ.cm2)
Figure 1. Schematic diagram of experimental setup.
Acknowledgements
The authors gratefully acknowledge financial support
from NSF (CBET-0748063), DOE-EERE through
University of Hawaii-Hawaii Natural Energy Institute
(DE-EE0000467).
Vent
Anode Water Trap
Cell Voltage (V)
The objective of this work is to investigate the effect of
cationic contaminants on polymer electrolyte fuel cell
(PEFC) performance. Four foreign cations (Ba2+, Ca2+,
Al3+, K+) were chosen as the contaminants in this study
due to their prevalence and chemical structure (e.g.
valence). Figure 1 shows the schematic diagram of
experimental setup for the in-situ injection of cationic
contaminants. After baseline test with DI water from the
nebulizer, contaminants are injected into the cathode of
the PEFC as perchlorate (ClO4-) salt solutions with dry air
from the nebulizer. Recovery tests are done by switching
back to DI water from the nebulizer. The current density
and operating conditions are kept constant throughout the
tests.
Figure 2 shows the cell voltage of the contaminated
cells during the current hold test (1 A/cm2). The cells with
Ba(ClO4)2 and Ca(ClO4)2 injection exhibit a little cell
voltage change during current hold. Compared with the
above two cells, the cells with Al(ClO4)3 and KClO4
injection show a lower cell performance with lower
voltage and higher resistance. After recovery tests by
switching back to DI water from the nebulizer, the cells
which were contaminated with Ba(ClO4)2 and Ca(ClO4)2
have a tendency to recover portion of the lost
performance; however, the cells with Al(ClO4)3 and
KClO4 injection don’t recover even though the run time
for contaminant injection is shorter than that of the above
two cells.
To monitor the PEFC performance, the polarization
curves before and after the contamination test are shown
in Figure 3. As shown in Figure 3, comparing with the
cells with Ba(ClO4)2 and Ca(ClO4)2 injection, the cells
with Al(ClO4)3 and KClO4 injection show a larger power
density and cell voltage reduction after contaminant test.
Data collected from experiments as well as post-test
characterization present evidence that cationic
contaminations can cause multiple modes of performance
loss, including loss of effective proton conductivity, mass
transport loss as well as loss of electrochemically active
surface area.
Anode Out
Power Density (mW/cm2)
b,c
Back Pressure
Regulator
Power Density (mW/cm2)
a,b
Vent
Cathode Water Trap
Hydrogen
before
and
after