skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Post-test evaluation of a solid oxide electrolysis stack.

Abstract

No abstract prepared.

Authors:
; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
NE
OSTI Identifier:
981308
Report Number(s):
ANL/CMT/CP-59082
TRN: US201012%%1292
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Conference
Resource Relation:
Conference: Annual Meeting of the American Nuclear Society; Jun. 24, 2007 - Jun. 28, 2007; Boston, MA
Country of Publication:
United States
Language:
ENGLISH
Subject:
22 GENERAL STUDIES OF NUCLEAR REACTORS; ELECTROLYSIS; EVALUATION; OXIDES

Citation Formats

Carter, J. D., Call, A., Ferrandon, M., Kropf, A. J., Maroni, V., Mawdsley, J., Myers, D., Yildiz, B., and Chemical Engineering. Post-test evaluation of a solid oxide electrolysis stack.. United States: N. p., 2007. Web.
Carter, J. D., Call, A., Ferrandon, M., Kropf, A. J., Maroni, V., Mawdsley, J., Myers, D., Yildiz, B., & Chemical Engineering. Post-test evaluation of a solid oxide electrolysis stack.. United States.
Carter, J. D., Call, A., Ferrandon, M., Kropf, A. J., Maroni, V., Mawdsley, J., Myers, D., Yildiz, B., and Chemical Engineering. Mon . "Post-test evaluation of a solid oxide electrolysis stack.". United States. doi:.
@article{osti_981308,
title = {Post-test evaluation of a solid oxide electrolysis stack.},
author = {Carter, J. D. and Call, A. and Ferrandon, M. and Kropf, A. J. and Maroni, V. and Mawdsley, J. and Myers, D. and Yildiz, B. and Chemical Engineering},
abstractNote = {No abstract prepared.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share:
  • The conclusions of this paper are: (1) stack degradation analysis - significant sources of degradation have been identified, (a) oxygen electrode delamination off the electrolyte and (b) chromium contamination of the oxygen electrode and bond layer; (2) electrode materials development - improved electrode materials have been demonstrated, Pr{sub 2}NiO{sub 4} oxygen electrodes show state-of-the-art performance without optimization of fabrication parameters.
  • The oxygen electrodes from two solid oxide electrolysis stacks that performed high-temperature steam electrolysis (HTSE) and produced hydrogen for 1000 and 2000 h, respectively, were examined using X-ray fluorescence, X-ray absorption near edge structure (XANES), four-point resistivity, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction and Raman micro-spectroscopy to determine possible causes for the degradation in stack performance over the test periods. These techniques yielded information such as elemental distribution, oxidation state, phases present, electrode delamination, and porosity within the electrode layers. From these studies, we found two phenomena that were likely the cause of increasingly poor oxygen electrode performancemore » over time. The first source of degradation was chromium substitution into the oxygen electrode bond layer, which serves to bond the cell to the flow field and interconnect. This is caused by migration of a chromium species from the bipolar plate. The effect of this is a significant increase in the electrical resistance of the bond layer material. The other source of degradation identified was oxygen electrode delamination. The cause of electrode delamination, which is locally catastrophic to the operation of the cell, is unclear; however, we will discuss two possible mechanisms that might cause this phenomenon.« less
  • An experimental study is under way to assess the performance of solid-oxide cells operating in the steam electrolysis mode for hydrogen production over a temperature range of 800 to 900ºC. Results presented in this paper were obtained from a ten-cell planar electrolysis stack, with an active area of 64 cm2 per cell. The electrolysis cells are electrolytesupported, with scandia-stabilized zirconia electrolytes (~140 µm thick), nickel-cermet steam/hydrogen electrodes, and manganite air-side electrodes. The metallic interconnect plates are fabricated from ferritic stainless steel. The experiments were performed over a range of steam inlet mole fractions (0.1 - 0.6), gas flow rates (1000more » - 4000 sccm), and current densities (0 to 0.38 A/cm2). Steam consumption rates associated with electrolysis were measured directly using inlet and outlet dewpoint instrumentation. Cell operating potentials and cell current were varied using a programmable power supply. Hydrogen production rates up to 100 Normal liters per hour were demonstrated. Values of area-specific resistance and stack internal temperatures are presented as a function of current density. Stack performance is shown to be dependent on inlet steam flow rate.« less
  • This paper presents results of recent experiments conducted at the INL studying coelectrolysis of steam and carbon dioxide in a 10-cell high-temperature solid-oxide electrolysis stack. Coelectrolysis is complicated by the fact that the reverse shift reaction occurs concurrently with the electrolytic reduction reactions. All reactions must be properly accounted for when evaluating results. Electrochemical performance of the stack was evaluated over a range of temperatures, compositions, and flow rates. The apparatus used for these tests is heavily instrumented, with precision mass-flow controllers, on-line dewpoint and CO2 sensors, and numerous pressure and temperature measurement stations. It also includes a gas chromatographmore » for analyzing outlet gas compositions. Comparisons of measured compositions to predictions obtained from a chemical equilibrium co-electrolysis model are presented, along with corresponding polarization curves. Results indicate excellent agreement between predicted and measured outlet compositions. Coelectrolysis significantly increases the yield of syngas over the reverse water gas shift reaction equilibrium composition. The process appears to be a promising technique for large-scale syngas production.« less
  • A new test stand has been developed at the Idaho National Laboratory for multi-kW testing of solid oxide electrolysis stacks. This test stand will initially be operated at the 4 KW scale. The 4 kW tests will include two 60-cell stacks operating in parallel in a single hot zone. The stacks are internally manifolded with an inverted-U flow pattern and an active area of 100 cm2 per cell. Process gases to and from the two stacks are distributed from common inlet/outlet tubing using a custom base manifold unit that also serves as the bottom current collector plate. The solid oxidemore » cells incorporate a negative-electrode-supported multi-layer design with nickel-zirconia cermet negative electrodes, thin-film yttria-stabilized zirconia electrolytes, and multi-layer lanthanum ferrite-based positive electrodes. Treated metallic interconnects with integral flow channels separate the cells and electrode gases. Sealing is accomplished with compliant mica-glass seals. A spring-loaded test fixture is used for mechanical stack compression. Due to the power level and the large number of cells in the hot zone, process gas flow rates are high and heat recuperation is required to preheat the cold inlet gases upstream of the furnace. Heat recuperation is achieved by means of two inconel tube-in-tube counter-flow heat exchangers. A current density of 0.3 A/cm2 will be used for these tests, resulting in a hydrogen production rate of 25 NL/min. Inlet steam flow rates will be set to achieve a steam utilization value of 50%. The 4 kW test will be performed for a minimum duration of 1000 hours in order to document the long-term durability of the stacks. Details of the test apparatus and initial results will be provided.« less