TY - JOUR
T1 - Impedance characterization of high temperature proton exchange membrane fuel cell stack under the influence of carbon monoxide and methanol vapor
AU - Jeppesen, Christian
AU - Polverino, Pierpaolo
AU - Andreasen, Søren Juhl
AU - Araya, Samuel Simon
AU - Sahlin, Simon Lennart
AU - Pianese, Cesare
AU - Kær, Søren Knudsen
PY - 2017/8
Y1 - 2017/8
N2 - This work presents a comprehensive mapping of electrochemical impedance measurements under the influence of CO and methanol vapor contamination of the anode gas in a high temperature proton exchange membrane fuel cell, at varying load current. Electrical equivalent circuit model parameters based on experimental evaluation of electrochemical impedance spectroscopy measurements were used to quantify the changes caused by different contamination levels. The changes are generally in good agreement with what is found in the literature. It is shown that an increased level of CO contamination resulted in an increase in the high frequency and intermediate frequency impedances. When adding CO and methanol to the anode gas, the low frequency part of the impedance spectrum is especially affected at high load currents, which is clearly seen as a result of the high load current resolution used in this work. The negative effects of methanol vapor are found to be more pronounced on the series resistance. When CO and methanol vapor are both present in anode gas, the entire frequency spectrum and thereby all the equivalent circuit model parameters are affected. It is also shown that the trends of contamination effects are similar for all the test cases, namely, CO alone, methanol alone and a mix of the two, suggesting that effects of methanol may include oxidation into CO on the catalyst layer.
AB - This work presents a comprehensive mapping of electrochemical impedance measurements under the influence of CO and methanol vapor contamination of the anode gas in a high temperature proton exchange membrane fuel cell, at varying load current. Electrical equivalent circuit model parameters based on experimental evaluation of electrochemical impedance spectroscopy measurements were used to quantify the changes caused by different contamination levels. The changes are generally in good agreement with what is found in the literature. It is shown that an increased level of CO contamination resulted in an increase in the high frequency and intermediate frequency impedances. When adding CO and methanol to the anode gas, the low frequency part of the impedance spectrum is especially affected at high load currents, which is clearly seen as a result of the high load current resolution used in this work. The negative effects of methanol vapor are found to be more pronounced on the series resistance. When CO and methanol vapor are both present in anode gas, the entire frequency spectrum and thereby all the equivalent circuit model parameters are affected. It is also shown that the trends of contamination effects are similar for all the test cases, namely, CO alone, methanol alone and a mix of the two, suggesting that effects of methanol may include oxidation into CO on the catalyst layer.
KW - Fuel cell
KW - PBI
KW - Electrochemical impedance spectroscopy
KW - CO
KW - Methanol vapor
KW - Equivalent electrical circuit
UR - http://www.scopus.com/inward/record.url?scp=85026390121&partnerID=8YFLogxK
U2 - 10.1016/j.ijhydene.2017.07.094
DO - 10.1016/j.ijhydene.2017.07.094
M3 - Journal article
AN - SCOPUS:85026390121
SN - 0360-3199
VL - 42
SP - 21901
EP - 21912
JO - International Journal of Hydrogen Energy
JF - International Journal of Hydrogen Energy
IS - 34
ER -