99/01300 Performance of planar single cell lanthanum gallate based solid oxide fuel cells

Solid oxide fuel cells (SOFCs) can be fueled with various gases, including carbon-containing compounds. High operating temperatures, exceeding 600 °C, and the presence of a porous, nickel-based SOFC anode, might lead to the formation of solid carbon particles from fuels such as carbon monoxide and other gases with hydrocarbon-based compounds. Carbon deposition on fuel electrode surfaces can cause irreversible damage to the cell, eventually destroying the electrode. Soot formation mechanisms are strictly related to electrochemical, kinetic, and thermodynamic conditions. In the current study, the effects of carbon deposition on the lifetime and performance of SOFCs were analyzed in-operando, both in single-cell and stack conditions. It was observed that anodic gas velocity has an impact on soot formation and deposition, thus it was also studied in depth. Single-anode-supported solid oxide fuel cells were fueled with gases delivered in such a way that the initial velocities in the anodic compartment ranged from 0.1 to 0.7 m/s. Both cell operation and post-mortem observations proved that the carbon deposition process accelerates at higher anodic gas velocity. Furthermore, single-cell results were verified in an SOFC stack operated in carbon-deposition regime by dry-coupling with a downdraft 150 kWth biomass gasifier.

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Increase in Availability of Solid Oxide Fuel Cells by Means of Parallel Connection of Cells

Journal of Fuel Cell Science and Technology ◽

10.1115/1.4006048 ◽

2012 ◽

Vol 9 (3) ◽

Cited By ~ 1

Author(s):

Hanno Stagge ◽

Lars Doerrer ◽

Ralf Benger ◽

Beck Hans-Peter

Keyword(s):

Fuel Cells ◽

Solid Oxide Fuel Cells ◽

Single Cell ◽

Single Cells ◽

Electric Energy ◽

Solid Oxide ◽

Oxide Fuel ◽

Parallel Connection ◽

In Series ◽

Storage Technologies

Fuel cells consist of single cells that are connected in series to form a stack. This increases output voltage and therefore decreases current-dependent power losses, but the electric current of the stack has to flow through each single cell. In case of an increase of resistance or a failure of just one single cell the whole stack is affected. The failure tolerance of a parallel connection is higher. The serial and parallel connection of single solid oxide fuel cells (SOFC) is compared under the aspects of failure probability, power drop and stress on the single cells. With both a highly linearized and a complex SOFC model simulations have been accomplished of the connection of two single cells in parallel and in serial configuration. Additionally different connection concepts of 16 single cells were examined. Finally, an outlook on different other source or storage technologies for electric energy like batteries and photovoltaic cells is given.

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Synthesis and characterization of strontium and magnesium substituted lanthanum gallate–nickel cermet anode for solid oxide fuel cells

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2006.11.011 ◽

2007 ◽

Vol 102 (2-3) ◽

pp. 125-131 ◽

Cited By ~ 12

Author(s):

Pradyot Datta ◽

Peter Majewski ◽

Fritz Aldinger

Keyword(s):

Fuel Cells ◽

Solid Oxide Fuel Cells ◽

Solid Oxide ◽

Lanthanum Gallate ◽

Synthesis And Characterization ◽

Oxide Fuel

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00/03381 High performance electrodes for reduced temperature solid oxide fuel cells with doped lanthanum gallate electrolyte I. NiSDC cermet an

Fuel and Energy Abstracts ◽

10.1016/s0140-6701(00)94454-0 ◽

2000 ◽

Vol 41 (6) ◽

pp. 380

Keyword(s):

Fuel Cells ◽

Solid Oxide Fuel Cells ◽

High Performance ◽

Solid Oxide ◽

Lanthanum Gallate ◽

Oxide Fuel ◽

Reduced Temperature

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Modification of Results From Computational-Fluid-Dynamics Simulations of Single-Cell Solid-Oxide Fuel Cells to Estimate Multicell Stack Performance

Journal of Fuel Cell Science and Technology ◽

10.1115/1.4002617 ◽

2010 ◽

Vol 8 (2) ◽

Cited By ~ 1

Author(s):

William J. Sembler ◽

Sunil Kumar

Keyword(s):

Fuel Cells ◽

Fuel Cell ◽

Solid Oxide Fuel Cells ◽

Single Cell ◽

Three Dimensional ◽

Solid Oxide ◽

Oxide Fuel ◽

Cfd Model ◽

Fuel Cell Performance ◽

Cfd Models

A typical single-cell fuel cell is capable of producing less than 1 V of direct current. Therefore, to produce the voltages required in most industrial applications, many individual fuel cells must typically be stacked together and connected electrically in series. Computational fluid dynamics (CFD) can be helpful to predict fuel-cell performance before a cell is actually built and tested. However, to perform a CFD simulation using a three-dimensional model of an entire fuel-cell stack can require a considerable amount of time and multiprocessor computing capability that may not be available to the designer. To eliminate the need to model an entire multicell assembly, a study was conducted to determine the incremental effect on fuel-cell performance of adding individual solid-oxide fuel cells (SOFCs) to a CFD model of a multicell stack. As part of this process, a series of simulations was conducted to establish a CFD-nodal density that would not only produce reasonably accurate results but could also be used to create and analyze the relatively large models of the multicell stacks. Full three-dimensional CFD models were then created of a single-cell SOFC and of SOFC stacks containing two, three, four, five, and six cells. Values of the voltages produced when operating with various current densities, together with temperature distributions, were generated for each of these CFD models. By comparing the results from each of the simulations, adjustment factors were developed to permit single-cell CFD results to be modified to estimate the performance of stacks containing multiple fuel cells. The use of these factors could enable fuel-cell designers to predict multicell stack performance using a CFD model of only a single cell.

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