DOI QR코드

DOI QR Code

Influence of the cathode catalyst layer thickness on the behaviour of an air breathing PEM fuel cell

  • Received : 2013.01.16
  • Accepted : 2014.07.30
  • Published : 2014.06.25

Abstract

Fuel cells of proton exchange membrane type (PEMFC) working with hydrogen in the anode and ambient air in the cathode ('air breathing') have been prepared and characterized. The cells have been studied with variable thickness of the cathode catalyst layer ($L_{CL}$), maintaining constant the platinum and ionomer loads. Polarization curves and electrochemical active area measurements have been carried out. The polarization curves are analyzed in terms of a model for a flooded passive air breathing cathode. The analysis shows that $L_{CL}$ affects to electrochemical kinetics and mass transport processes inside the electrode, as reflected by two parameters of the polarization curves: the Tafel slope and the internal resistance. The observed decrease in Tafel slope with decreasing $L_{CL}$ shows improvements in the oxygen reduction kinetics which we attribute to changes in the catalyst layer structure. A decrease in the internal resistance with $L_{CL}$ is attributed to lower protonic resistance of thinner catalyst layers, although the observed decrease is lower than expected probably because the electronic conduction starts to be hindered by more hydrophilic character and thicker ionomer film.

Keywords

Acknowledgement

Supported by : Ministry of Science and Innovation of Spain

References

  1. Bard, A.J. and Faulkner, L.R. (1980), Electrochemical Methods, Fundamentals and Applications, John Wiley & Sons, New York.
  2. Chang, H., Kim, J.R., Cho, J.H., Kim, H.K. and Choi, K.H. (2002), "Materials and processes for small fuel cells", Solid State Ionics 148, 601-606. https://doi.org/10.1016/S0167-2738(02)00125-X
  3. Chaparro, A.M., Ferreira-Aparicio, P., Folgado, M.A., Martin, A.J. and Daza, L. (2011), "Catalyst layers for proton exchange membrane fuel cells prepared by electrospray deposition on nafion membrane", J. Power Sources, 196, 4200-4208. https://doi.org/10.1016/j.jpowsour.2010.09.096
  4. Chaparro, A.M., Gallardo, B., Folgado, M.A., Martin, A.J. and Daza, L. (2009), "PEMFC electrode preparation by electrospray: Optimization of catalyst load and ionomer content", Catal. Today, 178, 237-241.
  5. Chaparro, A.M., Martin, A.J., Folgado, M.A., Gallardo, B. and Daza, L. (2009), "Comparative analysis of the electroactive area of Pt/C PEMFC electrodes in liquid and solid polymer contact by underpotential hydrogen adsorption/desorption", Int. J. Hydrogen Energy, 34, 4838-4846. https://doi.org/10.1016/j.ijhydene.2009.03.053
  6. Cruz-Manzo, S., Rama, P. and Chen, R. (2010), "The low current electrochemical mechanisms of the fuel cell cathode catalyst layer through an impedance study", J. Electrochem. Soc., 157(3), B400-B408. https://doi.org/10.1149/1.3280267
  7. Cutlip, M.B. (1975), "An approximate model for mass transfer with reaction in porous gas diffusion electrodes", Electrochim. Acta, 20, 767-773. https://doi.org/10.1016/0013-4686(75)85013-4
  8. Eikerling, M. (2006), "Water management in cathode catalyst layers of PEM fuel cells. a structure-based model", J. Electrochem. Soc., 153(3), E58-E70. https://doi.org/10.1149/1.2160435
  9. Fernandez-Moreno, J., Guelbenzu, G., Martin, A.J., Folgado, M.A., Ferreira-Aparicio, P. and Chaparro, A.M. (2013), "A portable system powered with hydrogen and one single air-breathing PEM fuel cell", App. Energy, 109, 60-66. https://doi.org/10.1016/j.apenergy.2013.03.076
  10. Giddey, S., Badwal, S.P.S., Ciacchi, F.T., Fini, D., Sexton, B.A., Glenn, F. and Leech, P.W. (2010), "Investigations on fabrication and lifetime performance of self - air breathing direct hydrogen micro fuel cells", Int J. Hydrogen Energy, 35, 2506-2516. https://doi.org/10.1016/j.ijhydene.2009.12.158
  11. Heinzel, A., Hebling, C., Muller, M., Zedda, M. and Muller, C. (2002), "Fuel cells for low power applications", J. Power Sources, 105, 250-255. https://doi.org/10.1016/S0378-7753(01)00948-X
  12. Hoare, J.P. (1967), Advances in Electrochemistry and Electrochemical Engineering, Vol. 6, Interscience, New York.
  13. Jiang, J. and Kucernak, A. (2012), "Mass transport and kinetics of electrochemical oxygen reduction at nanostructured platinum electrode and solid polymer electrolyte membrane interface", J. Sol. State Electrochem., 16, 2571-2579. https://doi.org/10.1007/s10008-012-1676-9
  14. Kinoshita, K. (1992), Electrochemical Oxygen Technology, John Wiley & Sons, New York.
  15. Kulikovsky, A.A. (2012), "A physical model for catalyst layer impedance", J. Electroanal. Chem., 669, 28-34. https://doi.org/10.1016/j.jelechem.2012.01.018
  16. Kusoglu, A, Kwong, A., Clark, K.T., Gunterman, H.P. and Weber, A.Z. (2012), "Water uptake of fuel-cell catalyst layers", J. Electrochem. Soc., 159(9), F530-F535. https://doi.org/10.1149/2.031209jes
  17. Lee, M., Uchida, M., Tryk, D.A., Uchida, H. and Watanabe, M. (2011), "The effectiveness of platinum/carbon electrocatalysts: Dependence on catalyst layer thickness and Pt alloy catalytic effects", Electrochim. Acta, 56, 4783-4790. https://doi.org/10.1016/j.electacta.2011.03.072
  18. de Levie, R. (1967), Advances in Electrochemistry and Electrochemical Engineering, Vol. 6, Interscience, New York
  19. Liu, L. and Eikerling, M. (2008), "Model of cathode catalyst layers for polymer electrolyte fuel cells: the role of porous structure and water accumulation", Electrochim. Acta, 53, 4435-4446. https://doi.org/10.1016/j.electacta.2008.01.033
  20. Malek, K., Mashio, T. and Eikerling, M. (2011), "Microstructure of catalyst layers in PEM fuel cells redefined: a computational approach", Electrocatal., 2, 141-157. https://doi.org/10.1007/s12678-011-0047-0
  21. Meyers, J.P. and Maynard, H.L. (2002), "Design considerations for miniaturized PEM fuel cells", J. Power Sources, 109, 76-88. https://doi.org/10.1016/S0378-7753(02)00066-6
  22. Neyerlin, k.C., Gu, W., Jorne, J. and Gasteiger, H.A. (2006), "Determination of Catalyst Unique Parameters for the Oxygen Reduction Reaction in a PEMFC", J. Electrochem. Soc., 153, A1955-A1963. https://doi.org/10.1149/1.2266294
  23. Parthasarathy, A., Srinivasan, S., Appleby, A.J. and Martin, C.R. (1992), "Pressure dependence of the oxygen reduction reaction at the platinum Microelectrode/Nafion interface: electrode kinetics and mass transport", J. Electrochem. Soc., 139(10), 2856-2862. https://doi.org/10.1149/1.2068992
  24. Stonehart, P. and Ross, P.N. (1976), "The use of porous electrodes to obtain kinetic rate constants for rapid reactions and adsorption isotherms of poisons", Electrochim. Acta, 21, 441-445. https://doi.org/10.1016/0013-4686(76)85123-7
  25. Vogel, W., Lundquist, J. and Bradford, A. (1972), "Reduction of oxygen on teflon-backed platinum black electrodes", Electrochim. Acta, 17, 1735-1744. https://doi.org/10.1016/0013-4686(72)85063-1
  26. Weiland, M., Wagner, S., Hahn, R. and Reichl, H. (2013), "Design and evaluation of a passive self-breathing micro fuel cell for autonomous portable applications", Int. J. Hydrogen Energy, 38, 440-446. https://doi.org/10.1016/j.ijhydene.2012.09.117