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Title: Measurement of Polarization Resistance of LSM + YSZ Electrodes on YSZ using AC and DC Methods
Most of the measurements of electrode polarization resistance are conducted using electrochemical impedance spectroscopy (EIS). The electrochemical devices, however, are typically used in a DC mode. The objective of the present work was to measure electrode polarization resistance using both EIS and DC techniques. A solid cylinder of 8YSZ of diameter ~1.17 cm and length ~5.00 cm was made by powder pressing followed by sintering. LSM + YSZ electrodes were applied on the two end surfaces of the cylinder upon which gold mesh was placed. Four Pt electrodes/probes were painted along the circumference. During DC measurements, DC voltage was applied across the end electrodes and potentials were measured at all four probes. The current was also measured. From these measurements electrode polarizations were estimated separately for the two electrodes as a function of current. EIS was conducted across the two end electrodes as well as across electrode-1 and probe-2, and across probe-2 and electrode-2. This allowed the determination of the polarization resistances of the two electrodes separately. Point by point additions of the electrode-1/probe-2 and probe-2/electrode-2 spectra matched the electrode-1/electrode-2 spectra. There was good agreement between the DC and the EIS measurements.  more » « less
Award ID(s):
1742696
PAR ID:
10100062
Author(s) / Creator(s):
Date Published:
Journal Name:
Fuel cells
ISSN:
1554-3951
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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