A 3D model for the free-breathing direct methanol fuel cell: Methanol crossover aspects and validations with current distribution measurements

A three-dimensional model has been developed for the free-breathing direct methanol fuel cell (DMFC) assuming steady-state isothermal and single-phase conditions. Especially the MeOH crossover phenomenon is investigated and the model validations are done using previous cathodic current distribution measurements. A free convection of air is modelled in the cathode channels and diffusion and convection of liquid (anode) and gaseous species (cathode) in the porous transport layers. The MeOH flow in the membrane is described with diffusion and protonic drag. The parameter ψ in the model describes the MeOH oxidation rate at the cathode and it is fitted according to the measured current distributions. The model describes the behaviour of the free-breathing DMFC, when different operating parameters such as cell temperature, MeOH concentration and flow rate are varied in a wide range. The model also predicts the existence of the experimentally observed electrolytic domains, i.e. local regions of negative current densities. Altogether, the developed model is in reasonable agreement with both the measured current distributions and polarization curves. The spatial information gained of mass transfer phenomena inside the DMFC is valuable for the optimization of the DMFC operating parameters.

[1]  R. J. Behm,et al.  The potential of model studies for the understanding of catalyst poisoning and temperature effects in polymer electrolyte fuel cell reactions , 2006 .

[2]  Chao-Yang Wang,et al.  Fundamental models for fuel cell engineering. , 2004, Chemical reviews.

[3]  Klaus Wippermann,et al.  DMFC: Galvanic or electrolytic cell? , 2006 .

[4]  T. Kallio,et al.  Relationship Between Methanol Permeability and Structure of Different Radiation‐Grafted Membranes , 2004 .

[5]  Mahlon Wilson,et al.  A printed circuit board approach to measuring current distribution in a fuel cell , 1998 .

[6]  Brant A. Peppley,et al.  A Review of Mathematical Models for Hydrogen and Direct Methanol Polymer Electrolyte Membrane Fuel Cells , 2004 .

[7]  Hongtan Liu,et al.  A three-dimensional mathematical model for liquid-fed direct methanol fuel cells , 2006 .

[8]  Nick Burke,et al.  Simultaneous Measurements of Species and Current Distributions in a PEFC under Low-Humidity Operation , 2005 .

[9]  Peter Lund,et al.  Determination of mass diffusion overpotential distribution with flow pulse method from current distribution measurements in a PEMFC , 2002 .

[10]  A. Weber,et al.  Modeling transport in polymer-electrolyte fuel cells. , 2004, Chemical reviews.

[11]  Erich Gülzow,et al.  Study of membrane electrode assemblies for direct methanol fuel cells , 2002 .

[12]  Kai Sundmacher,et al.  Analysis of the nonlinear dynamics of a direct methanol fuel cell , 2001 .

[13]  Eugene S. Smotkin,et al.  Methanol crossover in direct methanol fuel cells: a link between power and energy density , 2002 .

[14]  Electron transport in direct methanol fuel cells , 2007 .

[15]  Adélio Mendes,et al.  Proton exchange membranes for direct methanol fuel cells: Properties critical study concerning methanol crossover and proton conductivity , 2006 .

[16]  W. Lehnert,et al.  Current distribution mapping in polymer electrolyte fuel cells—A finite element analysis of measurement uncertainty imposed by lateral currents , 2006 .

[17]  Shimshon Gottesfeld,et al.  Methanol transport through Nafion membranes : Electro-osmotic drag effects on potential step measurements , 2000 .

[18]  A. Wokaun,et al.  An Approach to Measuring Locally Resolved Currents in Polymer Electrolyte Fuel Cells , 2004 .

[19]  Bing Wu,et al.  Current density distribution in PEFC , 2005 .

[20]  P. Lund,et al.  Mass transport in the cathode of a free-breathing polymer electrolyte membrane fuel cell , 2003 .

[21]  Erik Kjeang,et al.  A Parametric Study of Methanol Crossover in a Flowing Electrolyte Direct Methanol Fuel Cell , 2006 .

[22]  K. Kontturi,et al.  New ETFE-based membrane for direct methanol fuel cell , 2005 .

[23]  Hyunchul Ju,et al.  Experimental Validation of a PEM Fuel Cell Model by Current Distribution Data , 2004 .

[24]  T. Zhao,et al.  Abrupt Decline in the Open-Circuit Voltage of Direct Methanol Fuel Cells at Critical Oxygen Feed Rate , 2005 .

[25]  K. Kontturi,et al.  Current distribution measurements with a free-breathing direct methanol fuel cell using PVDF-g-PSSA and Nafion® 117 membranes , 2007 .

[26]  Angelika Heinzel,et al.  A review of the state-of-the-art of the methanol crossover in direct methanol fuel cells , 1999 .

[27]  Il Moon,et al.  Three-dimensional, two-phase, CFD model for the design of a direct methanol fuel cell , 2006 .

[28]  Siti Kartom Kamarudin,et al.  Overview on the challenges and developments of micro-direct methanol fuel cells (DMFC) , 2007 .

[29]  Chao-Yang Wang,et al.  Mathematical Modeling of Liquid-Feed Direct Methanol Fuel Cells , 2003 .

[30]  P. Lund,et al.  Measurement of current distribution in a free-breathing PEMFC , 2002 .

[31]  E. Smotkin,et al.  Array membrane electrode assemblies for high throughput screening of direct methanol fuel cell anode catalysts , 2002 .

[32]  Joakim Nordlund,et al.  A Model for the Porous Direct Methanol Fuel Cells Anode , 2002 .

[33]  Sarwan S. Sandhu,et al.  Prediction of methanol and water fluxes through a direct methanol fuel cell polymer electrolyte membrane , 2005 .

[34]  Carl L. Yaws,et al.  Handbook of Transport Property Data: Viscosity, Thermal Conductivity, and Diffusion Coefficients of Liquids and Gases , 1995 .

[35]  Chao-Yang Wang,et al.  In situ water distribution measurements in a polymer electrolyte fuel cell , 2003 .

[36]  K. Jeng,et al.  Modeling and simulation of a direct methanol fuel cell anode , 2002 .

[37]  K. Kontturi,et al.  Characterization of the novel ETFE-based membrane , 2006 .

[38]  Matti Noponen,et al.  Current distribution measurements in a PEFC with net flow geometry , 2004 .

[39]  A. Kulikovsky,et al.  The voltage–current curve of a direct methanol fuel cell: “exact” and fitting equations , 2002 .

[40]  Hongtan Liu,et al.  Effects of the electrical resistances of the GDL in a PEM fuel cell , 2006 .

[41]  Robert F. Savinell,et al.  Real‐Time Mass Spectrometric Study of the Methanol Crossover in a Direct Methanol Fuel Cell , 1996 .

[42]  C. Wieser,et al.  A new technique for two-dimensional current distribution measurements in electrochemical cells , 2000 .

[43]  Detlef Stolten,et al.  Recent developments of the measurement of the methanol permeation in a direct methanol fuel cell , 2002 .

[44]  J. Besenhard,et al.  Determination of methanol diffusion and electroosmotic drag coefficients in proton-exchange-membranes for DMFC , 2006 .

[45]  James M. Fenton,et al.  Characterization of Gas Diffusion Layers for PEMFC , 2004 .

[46]  Tsung-Kuang Yeh,et al.  A mathematical model for simulating methanol permeation and the mixed potential effect in a direct methanol fuel cell , 2006 .

[47]  Electrochemical Reactions in a DMFC under Open-Circuit Conditions , 2005 .

[48]  Keith Scott,et al.  Performance and modelling of a direct methanol solid polymer electrolyte fuel cell , 1997 .

[49]  Peter Lund,et al.  Effect of ambient conditions on performance and current distribution of a polymer electrolyte membrane fuel cell , 2003 .

[50]  D. Wilkinson,et al.  In-situ methods for the determination of current distributions in PEM fuel cells , 1998 .

[51]  A. Wiȩckowski,et al.  Stability of carbon monoxide adsorbed on nanoparticle Pt and Pt/Ru electrodes in sulfuric acid media , 2006 .

[52]  B. Seoane,et al.  Thermo-osmosis of mixtures of water and methanol through a Nafion membrane , 2006 .

[53]  J. Divisek,et al.  Process engineering of the direct methanol fuel cell , 2000 .

[54]  B. Seoane,et al.  Permeation of electrolyte water-methanol solutions through a Nafion membrane. , 2003, Journal of colloid and interface science.

[55]  A. Faghri,et al.  A transient, multi-phase and multi-component model of a new passive DMFC , 2006 .

[56]  Rong Chen,et al.  Mathematical modeling of a passive-feed DMFC with heat transfer effect , 2005 .