A Modeling Study of Porous Electrode Property Effects on Solid Oxide Fuel Cell Performance

2009 ◽  
Author(s):  
X. Xie ◽  
X. Xue
Keyword(s):  
Mathematical Model ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Reaction Zone ◽  
Polarization Curve ◽  
Porous Electrode ◽  
Solid Oxide ◽  
Design Parameters ◽  
Oxide Fuel ◽  
Active Reaction

A two-dimensional isothermal mathematical model is developed for an anode-supported planar solid oxide fuel cell (SOFC). The model takes into account the complex coupling effects of multi-physics processes including mass transfer, charge (ion/electron) transport, and electrochemical reaction. The SOFC multi-physics processes are numerically linked to SOFC global performance such as polarization curve. The model is validated using polarization curve as a metric with the experimental data from open literature. Since triple phase boundary reaction zone may vary from the vicinity of the electrolyte all the way to the entire electrode depending on selected materials and fabrication process, the effects of anode active reaction zone with different volumes are investigated comprehensively for a generic button cell using the developed mathematical model. The tradeoff design between active reaction zone volumes and other design parameters such as porosity and tortuosity of electrodes are also examined. Results show that porous composite electrode properties have very complex effects on SOFC performance. The results may provide a valuable guidance for high performance SOFC design and fabrication.

Application of an Anode Model to Investigate Physical Parameters in an Internal Reforming Solid-Oxide Fuel Cell

2005 ◽  
Vol 2 (2) ◽  
pp. 136-140 ◽  
Author(s):  
Eric S. Greene ◽  
Maria G. Medeiros ◽  
Wilson K. S. Chiu
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Structural Parameters ◽  
Porous Electrode ◽  
Cell Voltage ◽  
Solid Oxide ◽  
Physical Parameters ◽  
Oxide Fuel ◽  
Internal Reforming ◽  
Porous Anode

A one-dimensional model of chemical and mass transport phenomena in the porous anode of a solid-oxide fuel cell, in which there is internal reforming of methane, is presented. Macroscopically averaged porous electrode theory is used to model the mass transfer that occurs in the anode. Linear kinetics at a constant temperature are used to model the reforming and shift reactions. Correlations based on the Damkohler number are created to relate anode structural parameters and thickness to a nondimensional electrochemical conversion rate and cell voltage. It is shown how these can be applied in order to assist the design of an anode.

Lattice Boltzmann Simulation on Solid Oxide Fuel Cell Performance

2012 ◽  
Vol 472-475 ◽  
pp. 260-273
Author(s):  
Wang Jun Feng ◽  
Gong Wei Wu ◽  
You Sheng Xu
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Lattice Boltzmann ◽  
Catalyst Activity ◽  
Porous Electrode ◽  
Solid Oxide ◽  
Cell Performance ◽  
Lattice Boltzmann Model ◽  
Oxide Fuel ◽  
Internal Reforming

Based on models of a porous electrode, a more accurate lattice Boltzmann model for simulating the performance of a solid oxide fuel cell (SOFC) is proposed. Results show good agreement between simulated and measured data. The accuracy of concentration over potential prediction is crucial for low reactant concentrations. The addition of a small amount of air to the fuel yields fully stable performance without measurable carbon deposits detected on the catalyst layer or the fuel cell. Cell performance increases with the temperature. As a first test of the model, a benchmark problem regarding the performance of an internal reforming solid oxide fuel cell (IR-SOFC) is investigated. When the catalyst activity decreases, the rate of methane conversion decreases near the reactor

A Mathematical Model of a Solid Oxide Fuel Cell

1995 ◽  
Vol 142 (11) ◽  
pp. 3792-3800 ◽  
Author(s):  
Norman F. Bessette ◽  
William J. Wepfer ◽  
Jack Winnick
Keyword(s):  
Mathematical Model ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Solid Oxide ◽  
Oxide Fuel

Thick Film Processing Challenges in the Realisation of a Co-Fired Solid Oxide Fuel Cell Roll

2014 ◽  
Vol 87 ◽  
pp. 98-104 ◽  
Author(s):  
Mark Cassidy ◽  
Paul Connor ◽  
Marielle Etches ◽  
Yann Kalecheff ◽  
Marina MacHado ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Thick Film ◽  
Porous Electrode ◽  
Open Circuit ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Potential Applications ◽  
Key Aspects ◽  
Tape Cast

The Solid Oxide Fuel Cell Roll (SOFCRoll) is a novel design based on a double spiral. Combining structural advantages of tubular geometries with processing advantages of thick film methods, it utilises a single cofiring process. The initial concept used separate tape cast layers which were laminated before rolling. To optimise layer thickness to function, thinner screen printed layers were combined into the tape cast structure in 2nd generation cells. This presented several processing challenges, such as achieving dense electrolyte layers, maintaining porous electrode and current collecting layers and incorporation of integral gas channels. Performance has been promising with open circuit voltages close to 1V and cell power of over 400mW at 800°C, however cracking is still evident. Therefore further iterations are in development where thinner layers are sequentially cast, aiming to improve interfacial bonding and better match plasticity and burn out to reduce cracking. This paper reviews key aspects of understanding and development of the SOFRoll , the challenges that have been tackled and what challenges remain, along with future directions for development and potential applications for this device.

scholarly journals Mathematical model for the analysis of structure and optimal operational parameters of a solid oxide fuel cell generator

2014 ◽  
Vol 269 ◽  
pp. 632-644 ◽  
Author(s):  
Alberto Coralli ◽  
Hugo Villela de Miranda ◽  
Carlos Felipe Espiúca Monteiro ◽  
José Francisco Resende da Silva ◽  
Paulo Emílio Valadão de Miranda
Keyword(s):  
Mathematical Model ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Operational Parameters

Performance of an Integrated Microtubular Fuel Reformer and Solid Oxide Fuel Cell System

2010 ◽  
Vol 7 (3) ◽  
Author(s):  
John R. Izzo ◽  
Aldo A. Peracchio ◽  
Wilson K. S. Chiu
Keyword(s):  
Heat Transfer ◽  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Solid Oxide ◽  
Packed Bed Reactor ◽  
Limiting Current ◽  
Design Parameters ◽  
Heat Of Reaction ◽  
Oxide Fuel ◽  
Flow Rates

A numerical model is developed to study the performance of an integrated tubular fuel reformer and solid oxide fuel cell (SOFC) system. The model is used to study how the physical dimensions of the reformer, gas composition and the species flow rates of a methane feed stream undergoing autothermal reforming (ATR) affect the performance of an SOFC. The temperature in the reformer changes significantly due to the heat of reaction, and the reaction rates are very sensitive to the temperature and species concentrations. Therefore, it is necessary to couple the heat and mass transfer to accurately model the species conversion of the reformate stream. The reactions in the SOFC contribute much less to the temperature distribution than in the reformer and therefore the heat transfer in the SOFC is not necessary to model. A packed bed reactor is used to describe the reformer, where the chemical mechanism and kinetics are taken from the literature for nickel catalyst on a gamma alumina support. Heat transfer in the reformer’s gas and solid catalyst phases are coupled while the gas phase in the SOFC is at a uniform temperature. The SOFC gas species are modeled using a plug flow reactor. The models are in good agreement with experimental data. It is observed that the reformer temperature decreases with an increase in the reformer inlet water-to-fuel ratio and there is a slight decrease in the voltage of the SOFC from higher water content but an increase in limiting current density from a higher hydrogen production. The numerical results show that the flow rates and reformer length are critical design parameters because if not properly designed they can lead to incomplete conversion of the methane fuel to hydrogen in the reformer, which has the greatest impact on the SOFC performance in the integrated ATR reformer and SOFC system.

Prediction of Solid Oxide Fuel Cell Power System Performance Through Multi-Level Modeling

1995 ◽  
Vol 117 (4) ◽  
pp. 307-317 ◽  
Author(s):  
N. F. Bessette ◽  
W. J. Wepfer
Keyword(s):  
Fuel Cell ◽  
Solid Oxide Fuel Cell ◽  
Single Cell ◽  
Cell Model ◽  
Cell System ◽  
Solid Oxide ◽  
Design Parameters ◽  
Oxide Fuel ◽  
A Cell ◽  
Multi Level

This paper presents an integrated multi-level model of a solid oxide fuel cell system, which accounts for the effects of concentration, activation, and ohmic polarizations on single-cell performance, as well as the cell-to-cell interactions in a cell stack module. Furthermore, this model extends the work of Lu and Mahoney (1988) and Harvey and Richter (1994) by including the performance of a cell stack operating with a fuel reformer, heat exchangers, and a steam generator over a range of design parameters. This paper also demonstrates the procedure by which a single-cell model is scaled to a system model.

Sign in / Sign up

Export Citation Format

Share Document