Gas-dynamic and electro-chemical optimization of catalyst layers in high temperature polymeric electrolyte membrane fuel cells

Abstract We investigate the impact of catalyst (Pt) particle distribution on gas dynamics, electro-chemistry and consequently the performance of high temperature polymeric electrolyte membrane (HTPEM) fuel cells. We demonstrate that optimal distribution of catalyst can be used as an effective mitigation strategy for phosphoric acid loss and crossover of reagents through the membrane. First, we recognize that one of the reasons for performance degradation of HTPEM fuel cells originates from the gas dynamic action at the interface between the catalyst layer and membrane. Hence, we show that this can be greatly alleviated by choosing a proper catalyst particle distribution within the catalyst layer (CL). A simplified three-dimensional macroscopic model of the membrane electrode assembly (MEA) with catalyst layer made of three or five sublayers with different catalyst loadings, have been developed to analyze the effect of the proposed mitigation strategy on gas dynamics within the catalyst layer and the overall cell performance. This simplified macroscopic model predicts significant stress reduction (up to 4 times) using a feasible mitigation strategy, at the cost of only 9% efficiency reduction at high current densities.

[1]  Pablo Cañizares,et al.  Study of the influence of the amount of PBI–H3PO4 in the catalytic layer of a high temperature PEMFC , 2010 .

[2]  Robert M. Darling,et al.  Kinetic Model of Platinum Dissolution in PEMFCs , 2003 .

[3]  J.A.S. Bett,et al.  Potentiodynamic analysis of surface oxides on carbon blacks , 1973 .

[4]  J. C. Amphlett,et al.  Incorporation of voltage degradation into a generalised steady state electrochemical model for a PEM fuel cell , 2002 .

[5]  Y. Oono,et al.  Long-term cell degradation mechanism in high-temperature proton exchange membrane fuel cells , 2012 .

[6]  P. Cañizares,et al.  Study of flow channel geometry using current distribution measurement in a high temperature polymer , 2011 .

[7]  Werner Lehnert,et al.  Degradation of Solid Oxide Fuel Cell Anodes Due to Sintering of Metal Particles Correlated Percolation Model , 1997 .

[8]  Dane Morgan,et al.  Application of Pt Nanoparticle Dissolution and Oxidation Modeling to Understanding Degradation in PEM Fuel Cells , 2012 .

[9]  Keith Scott,et al.  A dynamic non-isothermal model of a laboratory intermediate temperature fuel cell using PBI doped ph , 2010 .

[10]  D. Stolten,et al.  Performance Analysis of HT-PEFC Stacks , 2012 .

[11]  Carmen M. Rangel,et al.  Characterization of MEA degradation for an open air cathode PEM fuel cell , 2012 .

[12]  B. Rambabu,et al.  Platinum/tin oxide/carbon cathode catalyst for high temperature PEM fuel cell , 2010 .

[13]  Lattice Boltzmann scheme for mixture modeling : analysis of the continuum diffusion regimes recovering , .

[14]  Werner Lehnert,et al.  Membrane electrode assemblies for high-temperature polymer electrolyte fuel cells based on poly(2,5-benzimidazole) membranes with phosphoric acid impregnation via the catalyst layers , 2009 .

[15]  Brian C. Benicewicz,et al.  Chapter 19 High-temperature polybenzimidazole-based membranes , 2009 .

[16]  Brian C. Benicewicz,et al.  Durability Studies of PBI‐based High Temperature PEMFCs , 2008 .

[17]  Michael Fowler,et al.  Degradation analysis and modeling of reinforced catalyst coated membranes operated under OCV conditions , 2008 .

[18]  Robert F. Savinell,et al.  High temperature proton exchange membranes based on polybenzimidazoles for fuel cells , 2009 .

[19]  A. Franco,et al.  Microstructure-based modeling of aging mechanisms in catalyst layers of polymer electrolyte fuel cells. , 2011, The journal of physical chemistry. B.

[20]  Edward F. Holby,et al.  Instability of Supported Platinum Nanoparticles in Low-Temperature Fuel Cells , 2007 .

[21]  Søren Knudsen Kær,et al.  Experimental characterization and modeling of commercial polybenzimidazole-based MEA performance , 2006 .

[22]  Hubert A. Gasteiger,et al.  Two Fuel Cell Cars In Every Garage , 2005 .

[23]  S. Radice,et al.  End groups in fluoropolymers , 1999 .

[24]  M. Gerard,et al.  Multiscale Model of Carbon Corrosion in a PEFC: Coupling with Electrocatalysis and Impact on Performance Degradation , 2008 .

[25]  Rodney L. Borup,et al.  Durability of PEFCs at High Humidity Conditions , 2005 .

[26]  Norman Munroe,et al.  Three dimensional modeling of high temperature PEM fuel cells , 2006 .

[27]  Shohji Tsushima,et al.  Degradation Mechanism of PEMFC under Open Circuit Operation , 2006 .

[28]  A. Weber.  Gas-Crossover and Membrane-Pinhole Effects in Polymer-Electrolyte Fuel Cells , 2008 .

[29]  P. Gómez‐Romero,et al.  Enhanced conductivity in polyanion-containing polybenzimidazoles. Improved materials for proton-exchange membranes and PEM fuel cells , 2003 .

[30]  E. U. Ubong,et al.  Three-Dimensional Modeling and Experimental Study of a High Temperature PBI-Based PEM Fuel Cell , 2009 .

[31]  N. Giordano,et al.  Electrochemical corrosion behavior of carbon black in phosphoric acid , 1988 .

[32]  R. Zengerle,et al.  Multiscale tomography of nanoporous carbon-supported noble metal catalyst layers , 2013 .

[33]  Günther G. Scherer,et al.  Study of radiation-grafted FEP-G-polystyrene membranes as polymer electrolytes in fuel cells , 1995 .

[34]  Hiroyuki Uchida,et al.  Decomposition mechanism of perfluorosulfonic acid electrolyte in polymer electrolyte fuel cells , 2006 .

[35]  L. J. Bregoli,et al.  A Reverse-Current Decay Mechanism for Fuel Cells , 2005 .

[36]  Robert M. Darling,et al.  Mathematical Model of Platinum Movement in PEM Fuel Cells , 2005 .

[37]  N. M. Zagudaeva,et al.  Degradation of high temperature MEA with PBI-H3PO4 membrane in a life test , 2009 .

[38]  T. Schmidt.  Durability and Degradation in High-Temperature Polymer Electrolyte Fuel Cells , 2006 .

[39]  P. Stonehart,et al.  Carbon substrates for phosphoric acid fuel cell cathodes , 1984 .

[40]  Robert M. Darling,et al.  Model of Carbon Corrosion in PEM Fuel Cells , 2006 .

[41]  Yanghua Tang,et al.  Polybenzimidazole-membrane-based PEM fuel cell in the temperature range of 120–200 °C , 2007 .

[42]  Thomas J. Schmidt,et al.  Properties of high-temperature PEFC Celtec®-P 1000 MEAs in start/stop operation mode , 2008 .

[43]  Pietro Asinari,et al.  Pore-scale modeling of fluid flow through gas diffusion and catalyst layers for high temperature proton exchange membrane (HT-PEM) fuel cells , 2014, Comput. Math. Appl..

[44]  Hubert A. Gasteiger,et al.  Handbook of fuel cells : fundamentals technology and applications , 2003 .

[45]  Shuang Ma,et al.  19F NMR studies of Nafion™ ionomer adsorption on PEMFC catalysts and supporting carbons , 2007 .

[46]  Jesse S. Wainright,et al.  Conductivity of PBI Membranes for High-Temperature Polymer Electrolyte Fuel Cells , 2004 .

[47]  S. Chung,et al.  NMR Studies of Mass Transport in High-Acid-Content Fuel Cell Membranes Based on Phosphoric Acid and Polybenzimidazole , 2007 .

[48]  J. Boon.  The Lattice Boltzmann Equation for Fluid Dynamics and Beyond , 2003 .