Journal of Applied Electrochemistry

, Volume 41, Issue 9, pp 1021–1032

Nonlinear frequency response analysis for the diagnosis of carbon monoxide poisoning in PEM fuel cell anodes

Authors

  • Thomas Kadyk
    • Max Planck Institute for Dynamics of Complex Technical Systems
    • Otto-von-Guericke University Magdeburg
    • Max Planck Institute for Dynamics of Complex Technical Systems
  • Kai Sundmacher
    • Max Planck Institute for Dynamics of Complex Technical Systems
    • Otto-von-Guericke University Magdeburg
Original Paper

DOI: 10.1007/s10800-011-0298-8

Cite this article as:
Kadyk, T., Hanke-Rauschenbach, R. & Sundmacher, K. J Appl Electrochem (2011) 41: 1021. doi:10.1007/s10800-011-0298-8

Abstract

Anodic CO poisoning of a PEMFC was analysed by nonlinear frequency response analysis (NFRA) in a differential H2/H2 cell. This special experimental setup excluded potential masking effects, emphasised the main mechanism of CO poisoning and made a simplified modelling approach possible. The main features of CO poisoning were investigated by means of steady state polarisation, EIS and NFRA. The main characteristics of CO poisoning in the NFRA spectra can be used as a “fingerprint” for diagnostic purposes.

Keywords

Polymer electrolyte membrane fuel cellNonlinear frequency response analysisHigher order frequency response functionCarbon monoxide

List of symbols

\( a_{{{\text{H}}_{{\text{2}}} {\text{O}}}}\)

Activity of water, [0 … 1]

A

Amplitude, A m−2

bc/h

Tafel slope of CO or hydrogen electrooxidation, V

bfc/fh

Ratio of desorption to adsorption rate constant for CO or hydrogen, [0 … 1]

CDL,A/C

Anodic or cathodic double layer capacity, F \({\text m}^{-2}_{\text {act}}\)

dM

Thickness of the membrane, m

F

Faraday constant, 96485.3 A s mol−1

kec/eh

Rate constant of CO or hydrogen electrooxidation, mol \({\text m}^{-2}_{\text {act}}\) s−1

kfc/fh

Rate constant of CO or hydrogen adsorption, mol \({\text m}^{-2}_{\text {act}}\) s−1

i

Current density, A m−2

p

Number of affected sites for Temkin adsorption

pA

Pressure at the anode, Pa

rCO/Hads/des/ox

Rates of CO or hydrogen adsorption, desorption or oxidation, mol \({\text m}^{-2}_{\text {act}}\) s−1

RM

Membrane resistance, \(\Upomega\, \hbox{m}^{-2}_{geom}\)

Ucell

Cell voltage, V

xCO/H

Mole fraction of CO or hydrogen, [0… 1]

Greek

\( \delta(\Updelta G_{\text{CO}}) \)

Variation of adsorption free energy between \(\Uptheta_{\text{CO}}=0\) and \(\Uptheta_{\text{CO}}=1, \hbox{J mol}^{-1}\)

\( \delta(\Updelta E_H) \)

Change in activation energy for hydrogen dissociative adsorption near CO occupied site, J mol−1

\( \epsilon \)

Roughness factor, \({\text m}^{2}_{\text {act}}\,{\text m}^{-2}_{\text {geom}}\)

ηA/C

Anode or cathode overpotential, V

\( \Uptheta_{\text{CO/H}} \)

Coverage of catalyst with CO or hydrogen, [0 … 1]

\( \Uptheta_{\text{Pt}} \)

Free active Pt catalyst sites, [0 … 1]

κ

Conductivity of the membrane, S m−1

ρ

Molar area density of active sites, mol \({\text m}^{-2}_{\text {act}}\)

Subscripts

0

Reference conditions

A

Anode

act

Active area

C

Cathode

CO

Carbon monoxide

eh

Electrooxidation of hydrogen

ec

Electrooxidation of carbon monoxide

fh

Adsorption of hydrogen

fc

Adsorption of carbon monoxide

geom

Geometric area

H

Hydrogen

H2O

Water

Pt

Platinum

Superscripts

ads

Adsorption

des

Desorption

ox

Oxidation

red

Reduction

Copyright information

© Springer Science+Business Media B.V. 2011