Performance of solid oxide fuel cells approaching the two-dimensional limit
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138 (United States)
We model electrochemical kinetics and physical conduction mechanisms for carrier transport in electrolyte membranes to determine the limits of dimensionality reduction (down to 1 nm) on maximum power output of solid oxide fuel cells with symmetric Pt electrodes. Using Y-doped ZrO{sub 2}, we find a minimum thickness of ∼6 nm to realize near ideal chemical potential in such fuel cells, which is limited by electronic breakdown when approaching the dielectric breakdown strength. For larger electrolyte thicknesses, the greatest source of electronic leakage influencing power loss is from Ohmic transport of minority carriers and emission of trapped carriers. For porous metallic electrodes, an ideal microstructure with the particle size comparable to particle spacing dimensions is found to accurately model experimental results. The role of electronic trap states in the electrolyte band gap on power density characteristics is highlighted.
- OSTI ID:
- 22273458
- Journal Information:
- Journal of Applied Physics, Vol. 115, Issue 17; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Abrupt current increase due to space-charge-limited conduction in thin nitride--oxide stacked dielectric system
Boosting solid oxide fuel cell performance via electrolyte thickness reduction and cathode infiltration
Related Subjects
SUPERCONDUCTIVITY AND SUPERFLUIDITY
36 MATERIALS SCIENCE
CHARGE CARRIERS
COMPARATIVE EVALUATIONS
DIELECTRIC MATERIALS
DOPED MATERIALS
ELECTRIC CONDUCTIVITY
ELECTROCHEMISTRY
ELECTRODES
ELECTROLYTES
MEMBRANES
MICROSTRUCTURE
PARTICLE SIZE
PERFORMANCE
POROUS MATERIALS
POTENTIALS
POWER DENSITY
POWER LOSSES
SOLID OXIDE FUEL CELLS
THICKNESS
TRAPPING
ZIRCONIUM OXIDES