0
Research Paper

A Model of a High-Temperature Direct Methanol Fuel Cell

[+] Author and Article Information
K. Scott

e-mail: k. scott@newcastle.ac.uk

M. Mamlouk

School of Chemical Engineering
and Advanced Materials,
University of Newcastle Upon Tyne,
Merz Court,
Newcastle-Upon-Tyne NE1 7RU, UK

Contributed by the Advanced Energy Systems Division of ASME for publication in the Journal of Fuel Cell Science and Technology. Manuscript received March 7, 2011; final manuscript received October 5, 2012; published online August 20, 2013. Assoc. Editor: Jacob Brouwer.

J. Fuel Cell Sci. Technol 10(5), 051003 (Aug 20, 2013) (12 pages) Paper No: FC-11-1037; doi: 10.1115/1.4024833 History: Received March 07, 2011; Revised October 05, 2012

A steady-state, isothermal, one-dimensional model of a direct methanol proton exchange membrane fuel cell (PEMFC), with a polybenzimidazole (PBI) membrane, was developed. The electrode kinetics were represented by the Butler–Volmer equation, mass transport was described by the multicomponent Stefan–Maxwell equations and Darcy's law, and the ionic and electronic resistances described by Ohm's law. The model incorporated the effects of temperature and pressure on the open circuit potential, the exchange current density, and diffusion coefficients, together with the effect of water transport across the membrane on the conductivity of the PBI membrane. The influence of methanol crossover on the cathode polarization is included in the model. The polarization curves predicted by the model were validated against experimental data for a direct methanol fuel cell (DMFC) operating in the temperature range of 125–175 °C. There was good agreement between experimental and model data for the effect of temperature and oxygen/air pressure on cell performance. The fuel cell performance was relatively poor, at only 16 mW cm−2 peak power density using low concentrations of methanol in the vapor phase.

Copyright © 2013 by ASME
Your Session has timed out. Please sign back in to continue.

References

Wainright, J. S., Wang, J. T., and Savinell, R. F., 1996, “Direct Methanol Fuel Cells Using Acid Doped Polybenzimidazole as a Polymer Electrolyte,” Intersociety Energy Conversion Engineering Conference, 2, pp. 1107–1111.
Lobato, J., Cañizares, P., Rodrigo, M. A., Linares, J. J., and López-Vizcaíno, R., 2008, “Performance of a Vapor-Fed Polybenzimidazole (PBI)-Based Direct Methanol Fuel Cell,” Energy Fuels, 22(5), pp. 3335–3345 [CrossRef].
Kadirgan, F., and Savadogo, O., 2004, “Methanol Crossover Through Modified Nafion Proton Exchange Membrane,” Russ. J. Electrochem., 40(11), pp. 1141–1145. [CrossRef]
Liu, Z., Wainright, J. S., and Savinell, R. F., 2004, “High-Temperature Polymer Electrolytes for PEM Fuel Cells: Study of the Oxygen Reduction Reaction (ORR) at a Pt-Polymer Wlectrolyte Interface,” Chem. Eng. Sci., 59(22–23), pp. 4833–4838. [CrossRef]
Gubler, L., Denis, K., Jorg, B., Omer, U., Thomas, J. S., and Gunther, G. S., 2007, “Celtec-V,” J. Electrochem. Soc., 154(9), pp. B981–B987. [CrossRef]
He, C., Kunz, H. R., and Fenton, J. M., 1997, “Evaluation of Platinum-Based Catalysts for Methanol Electro-Oxidation in Phosphoric Acid Electrolyte,” J. Electrochem. Soc., 144(3), pp. 970–979. [CrossRef]
Pu, H., Liu, Q., and Liu, G., 2004, “Methanol Permeation and Proton Conductivity of Acid-Doped Poly(N-ethylbenzimidazole) and Poly(N-methylbenzimidazole),” J. Membrane Sci., 241(2), pp. 169–175. [CrossRef]
Nordlund, J., and Lindbergh, G., 2004, “Temperature-Dependent Kinetics of the Anode in the DMFC,” J. Electrochem. Soc., 151(9), pp. A1357–A1362. [CrossRef]
Baxter, S. F., Battaglia, V. S., and White, R. E., 1999, “Methanol Fuel Cell Model: Anode,” J. Electrochem. Soc., 146(2), pp. 437–447. [CrossRef]
Ge, J., and Liu, H., 2006, “A Three-Dimensional Mathematical Model for Liquid-Fed Direct Methanol Fuel Cells,” J. Power Sources, 160(1), pp. 413–421. [CrossRef]
Liu, W., and Wang, C. Y., 2007, “Three-Dimensional Simulations of Liquid Feed Direct Methanol Fuel Cells,” J. Electrochem. Soc., 154, pp. B352–B361. [CrossRef]
Chen, C. H. and Yeh, T. K., 2006, “A Mathematical Model for Simulating Methanol Permeation and the Mixed Potential Effect in a Direct Methanol Fuel Cell,” J. Power Sources, 160(2), pp. 1131–1141. [CrossRef]
Murgia, G., Pisani, L., Shukla, A. K., and Scott, K., 2003, “A Numerical Model of a Liquid-Feed Solid Polymer Electrolyte DMFC and Its Experimental Validation,” J. Electrochem. Soc., 150(9), pp. A1231–A1245. [CrossRef]
Mamlouk, M., Scott, K., and Hidayati, N., 2011, “High Temperature Direct Methanol Fuel Cell Based on Phosphoric Acid PBI Membrane-Article #061009,” ASME J. Fuel Cell Sci. Technol., 8(6), pp. 1–8 [CrossRef].
Mamlouk, M., 2008, “Investigation of High Temperature Polymer Electrolyte Membrane Fuel Cells,” School of Chemical Engineering and Advance Materials, Newcastle University, Newcastle Upon Tyne, UK.
Yaws, C. L., 2003, Yaws' Handbook of Thermodynamic and Physical Properties of Chemical Compounds, Knovel, http://www.knovel.com/web/portal/browse/display?_EXT_KNOVEL_DISPLAY_bookid=667&VerticalID=0.
Liu, Z., Wainright, J. S., Litt, M. H., and Savinell, R. F., 2006, “Study of the Oxygen Reduction Reaction (ORR) at Pt Interfaced With Phosphoric Acid Doped Polybenzimidazole at Elevated Temperature and Low Relative Humidity,” Electrochim. Acta, 51(19), pp. 3914–3923. [CrossRef]
Scott, K., Pilditch, S., and Mamlouk, M., 2007, “Modelling and Experimental Validation of a High Temperature Polymer Electrolyte Fuel Cell,” J. Appl. Electrochem., 37, pp. 1245–1259. [CrossRef]
Scott, K., and Mamlouk, M., 2009, “A Cell Voltage Equation for an Intermediate Temperature Proton Exchange Membrane Fuel Cell,” Int. J. Hydrogen Energy, 34(22), pp. 9195–9202. [CrossRef]
Scott, K. and Mamlouk, M., 2011, “A Study of Oxygen Reduction on Carbon-Supported Platinum Fuel Cell Electrocatalysts in Polybenzimidazole/Phosphoric Acid,” Proc. IMechE Part A: J. Power and Energy225(2), pp. 161–174. [CrossRef]
Watanabe, M., Genjima, Y., and Turumi, K., 1997, “Direct Methanol Oxidation on Platinum Electrodes With Ruthenium Adatoms in Hot Phosphoric Acid,” J. Electrochem. Soc., 144(2), pp. 423–427. [CrossRef]
Wainright, J. S., Wang, J. T., Weng, D., Savinell, R. F., and Litt, M., 1995, “Acid-Doped Polybenzimidazoles—A New Polymer Electrolyte.” J. Electrochem. Soc., 142(7), pp. L121–L123. [CrossRef]
Jones, D. J. and Roziere, J., 2001, “Recent Advances in the Functionalisation of Polybenzimidazole and Polyetherketone for Fuel Cell Applications,” J. Membrane Sci., 185(1), pp. 41–58. [CrossRef]
Mamlouk, M., and Scott, K., 2011, “A Study of Oxygen Reduction on Carbon-Supported Platinum Fuel Cell Electrocatalysts in Polybenzimidazole/Phosphoric Acid,” Proc. IMechE A J. Power Energy, 225(2), pp. 161–174. [CrossRef]
Wasmus, S., Wang, J. T., and Savinell, R. F., 1995, “Real-Time Mass Spectrometric Investigation of the Methanol Oxidation in a Direct Methanol Fuel Cell,” J. Electrochem. Soc., 142(11), pp. 3825–3833. [CrossRef]
Ma, Y. L., Wainright, J. S., Litt, M. H., and Savinell, R. F., 2004, “Conductivity of PBI Membranes for High-Temperature Polymer Electrolyte Fuel Cells,” J. Electrochem. Soc., 151(1), pp. A8–A16. [CrossRef]
Hoare, J., 1962, “Rest Potentials in the Platinum-Oxygen-Acid System,” J. Electrochem. Soc., 109(9), pp. 858–865. [CrossRef]
Thacker, R. and Hoare, J., 1971, “Sorption of Oxygen From Solution by Noble Metals,” Electroanal. Chem. Interfac. Electrochem., 30(1), pp. 1–14. [CrossRef]
Wainright, J. S., Wang, J. T., and Savinell, R. F., 1996, “Direct Methanol Fuel Cells Using Acid Doped Polybenzimidazole as a Polymer Electrolyte,” Intersociety Energy Conversion Engineering Conference, Washington, DC.
Wang, J. T., Lin, W. F., Weber, M., Wasmus, S., and Savinell, R. F., 1998, “Trimethoxymethane as an Alternative Fuel for a Direct Oxidation PBI Polymer Electrolyte Fuel Cell,” Electrochim. Acta, 43(24), pp. 3821–3828. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Schematic diagrams of the anode and cathode 1D model cross section regions. Anode: AF—flow channel, AD—diffusion layer, AM—microporous layer, AR—catalyst layer. Membrane: M—membrane. Cathode: CF—flow channel, CD—diffusion layer, CM—microporous layer, CR—catalyst layer.

Grahic Jump Location
Fig. 2

Thin film model in a DMFC

Grahic Jump Location
Fig. 3

Anode current density versus potential. Temperature 150 °C and 1 M methanol vapor.

Grahic Jump Location
Fig. 4

Cathode current versus potential for conditions for air and oxygen. γ=0.5. □—air, temperature 150 °C, •—oxygen, temperature 150 °C.

Grahic Jump Location
Fig. 5

(a) Comparison between model and experiment for anode polarization, at different temperatures. 1 g m−2, 60% PtRu/C 20% Ru, width 12 μm, pressure 1 bar (atmospheric pressure), and 1 M methanol feed. Continuous line, experimental 125 °C ; line with single dashes, experimental 150 °C ; line with double dashes, experimental 175 °C ; model 125 °C—; model 150 °C—♦; model 175 °C—○. (b) Comparison between model and experiment for anode polarization, at different temperatures. Plotted for loading 1 mg cm−2, 60% PtRu/C 20% Ru, width 12 μm, pressure 1 bar (atmospheric pressure), and 2 M methanol feed. Continuous line, experimental 125 °C ; line with single dashes, experimental 150 °C ; line with double dashes, experimental 175 °C ; model 125 °C—; model 150 °C—♦; model 175 °C—○.

Grahic Jump Location
Fig. 6

(a) Comparison between model and experiment for cathode polarization, at different temperatures. Loading 0.5 mg cm−2, 60% PtRu/C 20% Ru, width 12 μm, pressure 1 bar (atmospheric pressure), air feed. Continuous line, experimental 125 °C ; line with single dashes, experimental 150 °C ; line with double dashes, experimental 175 °C ; model 125 °C—; model 150 °C—♦; model 175 °C—○. (b) Comparison between model and experiment for cathode polarization, at different temperatures. Loading 0.5 mg cm−2, 60% PtRu/C 20% Ru, width 12 μm, pressure 1 bar (atmospheric pressure), oxygen feed. Continuous line, experimental 125 °C ; line with single dashes, experimental 150 °C ; line with double dashes, experimental 175 °C ; model 125 °C—; model 150 °C—♦; model 175 °C—○.

Grahic Jump Location
Fig. 7

Comparison between model and experiment fuel cell polarization at different temperatures. Air cathode and 1 M methanol. Continuous line, experimental 125 °C ; line with single dashes, experimental 150 °C ; line with double dashes, experimental 175 °C ; continuous thick line, experimental power 125 °C ; thick line, with single dashes, experimental power density 150 °C ; thick line with double dashes, experimental power 175 °C ; model 125 °C—; model 150 °C—♦; model 175 °C—○; model power cell 125 °C—○; model power cell 150 °C—□; model power cell 175 °C—▴

Grahic Jump Location
Fig. 8

Comparison between model and experiment for fuel cell polarization. Oxygen cathode and 1 M methanol. Continuous line, experimental 125 °C, ; line with single dashes, experimental 150 °C, ; line with double dashes, experimental 175 °C, ; continous thick line, experimental power 125 °C, ; thick line with single dashes, experimental power density 150 °C, ; thick line with double dashes, experimental power 175 °C, ; model 125 °C—; model 150 °C—♦; model 175 °C—○; model power cell 125 °C—○; model power cell 150 °C—□; model power cell 175 °C—▴

Grahic Jump Location
Fig. 9

(a) Modulus of electronic current density in the anode catalyst layer. •—150 mV, ○—310 mV, ▴—450 mV. (b) Modulus of ionic current density in the anode catalyst layer. •—150 mV, □—310 mV, ▴—450 mV.

Grahic Jump Location
Fig. 10

(a) Methanol concentration at the thin film/PtRu surface (the site of the reaction) in the anode. Potentials: ▴—150 mV, •—450 mV. (b) Methanol concentration at the thin film/PtRu surface (the site of the reaction) at the anode. The thin film thickness was increased by an order of magnitude. ▴—150 mV, •—450 mV.

Grahic Jump Location
Fig. 11

Oxygen concentration on the thin film/Pt surface (the site of the reaction), cathode, model results. ▴—400 mV, •—100 mV. The cathode catalyst x coordinates range from 20 μm (membrane) to 35 μm.

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In