elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Cr2O3 scale growth rates on metallic interconnectors derived from 40,000 h solid oxide fuel cell stack operation

Linder, Markus and Hocker, Thomas and Holzer, Lorenz and Friedrich, K. Andreas and Iwanschitz, Boris and Mai, Andreas and Schuler, J. Andreas (2013) Cr2O3 scale growth rates on metallic interconnectors derived from 40,000 h solid oxide fuel cell stack operation. Journal of Power Sources (243), pp. 508-518. Elsevier. DOI: 10.1016/j.jpowsour.2013.05.200 ISSN 0378-7753

[img] PDF - Registered users only
2MB

Abstract

The ohmic resistance caused by Cr2O3 scale formation on metallic interconnects (MICs) can significantly contribute to the overall degradation of SOFC stacks. For this reason oxide scale growth on Cr5Fe1Y2O3 (CFY) and Fe22Cr0.5Mn (Crofer) was investigated by scanning electron microscopy (SEM) from post-test samples that were either exposed to air at 850 C (furnace) or operated in Hexis planar SOFC-stacks under dual atmospheres (anode and cathode conditions) at temperatures around 900 C. The study includes unique test results from a stack operated for 40,000 h. To analyze inhomogeneity in scale thicknesses a dedicated statistical image analysis method has been applied. SEM images were used to compare the structural phenomena related to MIC oxidation at different sample locations. The observed differences between different sample locations may relate to locally different conditions (temperature, pO2, H2O/O2-ratio). Cr2O3 scale growth on the anode side is found to be approximately twice as fast in comparison to the scale growth on cathode side. Finally, based on our time lapse analyses with extensive sampling it can be concluded that reliable predictions of scale growth requires statistical analyses over a period that covers at least a quarter (10,000 h) of the required SOFC stack lifetime (40,000 h).

Item URL in elib:https://elib.dlr.de/84876/
Document Type:Article
Title:Cr2O3 scale growth rates on metallic interconnectors derived from 40,000 h solid oxide fuel cell stack operation
Authors:
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Linder, Markus Hexis AGUNSPECIFIED
Hocker, ThomasHexis AGUNSPECIFIED
Holzer, LorenzHexis AGUNSPECIFIED
Friedrich, K. Andreasandreas.friedrich (at) dlr.deUNSPECIFIED
Iwanschitz, Boris Hexis AGUNSPECIFIED
Mai, AndreasHexis AGUNSPECIFIED
Schuler, J. AndreasHexis AGUNSPECIFIED
Date:June 2013
Journal or Publication Title:Journal of Power Sources
Refereed publication:Yes
Open Access:No
Gold Open Access:No
In SCOPUS:Yes
In ISI Web of Science:Yes
DOI :10.1016/j.jpowsour.2013.05.200
Page Range:pp. 508-518
Publisher:Elsevier
ISSN:0378-7753
Status:Published
Keywords:SOFC Interconnect Scale growth rate law Chromium oxide Degradation prediction Dual atmospheres
HGF - Research field:Energy
HGF - Program:Efficient Energy Conversion and Use (old)
HGF - Program Themes:Fuel Cells (old)
DLR - Research area:Energy
DLR - Program:E EV - Energy process technology
DLR - Research theme (Project):E - Elektrochemische Prozesse (old)
Location: Stuttgart
Institutes and Institutions:Institute of Engineering Thermodynamics > Electrochemical Energy Technology
Deposited By: Friedrich, Prof.Dr. Kaspar Andreas
Deposited On:30 Oct 2013 11:50
Last Modified:30 Oct 2013 11:50

Repository Staff Only: item control page

Browse
Search
Help & Contact
Information
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.