Solid oxide fuel cells are fuel cells that operate in a temperature region between 650 °C and 1000 °C by using an oxygen ion conductor as the electrolyte. The ionic transported species are oxygen ions that allow the use of both hydrogen and carbon monoxide as well as directly applied methane as fuels while the oxidant is oxygen provided by air. The state-of-the art SOFC consists of an yttria-stabilized zirconia (YSZ) as the electrolyte, a ceramic metallic composite, a Ni-YSZ cermet as the fuel electrode and a ceramic composite of strontium doped lanthanum manganite and YSZ as the air electrode. The SOFC is, therefore, an all-solid state system for which different designs may apply.
Both tubular and planar concepts of SOFC cells and stacks have been developed since the 1960s. The best developed SOFC system is the tubular cell design from Westinghouse (now Siemens Westinghouse Power Corporation), operating at temperatures around 1000 °C. Planar cell designs which allow operating temperatures between 650 °C and 850 °C by using an anode supported electrolyte are under development. The two different concepts, the tubular and the planar design are described in detail and the impact of the supporting component upon important aspects as operating conditions, power density, sealing and contacting are addressed.
SOFC systems have mainly been considered for stationary generation of electricity in combined cycles and co-generation plants operating on natural gas or oil. New applications are opened in the area of remote power supply in residential but also automotive applications. Principles of systems considered for each application are described in the last section.
Keywords:
solid oxide fuel cell;
hydrogen;
carbon monoxide;
methane;
hydrocarbon fuel;
yttria-stabilized zirconia (YSZ);
cell designs: tubular;
planar;
anode supported;
co-generation systems;
automotive applications
[1]
M. Mogensen,et al.
Performance/structure correlation for composite SOFC cathodes
,
1996
.
[2]
P. Holtappels,et al.
Fabrication and performance of advanced multi-layer SOFC cathodes
,
2002
.
[3]
Raymond J. Gorte,et al.
Direct Oxidation of Liquid Fuels in a Solid Oxide Fuel Cell
,
2001
.
[4]
Mogens Bjerg Mogensen,et al.
Reaction of CO/CO2 gas mixtures on Ni–YSZ cermet electrodes
,
1999
.
[5]
N. Minh.
Ceramic Fuel Cells
,
1993
.
[6]
K. Wippermann,et al.
Catalysis of the electrochemical processes on solid oxide fuel cell cathodes
,
1996
.
[7]
Ernst Riensche,et al.
Optimization of a 200 kW SOFC cogeneration power plant. Part I: Variation of process parameters
,
1998
.
[8]
Miho Honda,et al.
Intermediate Temperature Solid Oxide Fuel Cells Using a New LaGaO3 Based Oxide Ion Conductor I. Doped as a New Cathode Material
,
1998
.
[9]
Martin Schmidt.
The Hexis Project
,
1998
.
[10]
A. Naoumidis,et al.
Chemical Compatibility between Strontium‐Doped Lanthanum Manganite and Yttria‐Stabilized Zirconia
,
1995
.
[11]
Mogens Bjerg Mogensen,et al.
Impedance of Solid Oxide Fuel Cell LSM/YSZ Composite Cathodes
,
2001
.
[12]
M. Mogensen,et al.
Composite Electrodes in Solid Oxide Fuel Cells and Similar Solid State Devices
,
2000
.
[13]
Mogens Bjerg Mogensen,et al.
Gas Diffusion Impedance in Characterization of Solid Oxide Fuel Cell Anodes
,
1999
.
[14]
Simulated Dynamics of Underpotential Deposition of Cu with Sulfate on Au(111)
,
1997,
cond-mat/9709320.