Diffusion and Gas Conversion Analysis of Solid Oxide Fuel Cells at Loads via AC Impedance
Impedance measurements were conducted under practical load conditions in solid oxide fuel cells of differing sizes. For a 2 cm2 button cell, impedance spectra data were separately measured for the anode, cathode, and total cell. Improved equivalent circuit models are proposed and applied to simulate...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2011-01-01
|
| Series: | International Journal of Electrochemistry |
| Online Access: | http://dx.doi.org/10.4061/2011/465452 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850224474293534720 |
|---|---|
| author | Robert U. Payne Ying Zhu Wenhua H. Zhu Mark S. Timper S. Elangovan Bruce J. Tatarchuk |
| author_facet | Robert U. Payne Ying Zhu Wenhua H. Zhu Mark S. Timper S. Elangovan Bruce J. Tatarchuk |
| author_sort | Robert U. Payne |
| collection | DOAJ |
| description | Impedance measurements were conducted under practical load conditions in solid oxide fuel cells of differing sizes. For a 2 cm2 button cell, impedance spectra data were separately measured for the anode, cathode, and total cell. Improved equivalent circuit models are proposed and applied to simulate each of measured impedance data. Circuit elements related to the chemical and physical processes have been added to the total-cell model to account for an extra relaxation process in the spectra not measured at either electrode. The processes to which elements are attributed have been deduced by varying cell temperature, load current, and hydrogen concentration. Spectra data were also obtained for a planar stack of five 61 cm2 cells and the individual cells therein, which were fitted to a simplified equivalent circuit model of the total button cell. Similar to the button cell, the planar cells and stack exhibit a pronounced low-frequency relaxation process, which has been attributed to concentration losses, that is, the combined effects of diffusion and gas conversion. The simplified total-cell model approximates well the dynamic behavior of the SOFC cells and the whole stack. |
| format | Article |
| id | doaj-art-4e9ef42a12394f7a92d6bc2486d2daed |
| institution | OA Journals |
| issn | 2090-3537 |
| language | English |
| publishDate | 2011-01-01 |
| publisher | Wiley |
| record_format | Article |
| series | International Journal of Electrochemistry |
| spelling | doaj-art-4e9ef42a12394f7a92d6bc2486d2daed2025-08-20T02:05:36ZengWileyInternational Journal of Electrochemistry2090-35372011-01-01201110.4061/2011/465452465452Diffusion and Gas Conversion Analysis of Solid Oxide Fuel Cells at Loads via AC ImpedanceRobert U. Payne0Ying Zhu1Wenhua H. Zhu2Mark S. Timper3S. Elangovan4Bruce J. Tatarchuk5Center for Microfibrous Materials, Department of Chemical Engineering, 212 Ross Hall, Auburn University, AL 36849, USACenter for Microfibrous Materials, Department of Chemical Engineering, 212 Ross Hall, Auburn University, AL 36849, USACenter for Microfibrous Materials, Department of Chemical Engineering, 212 Ross Hall, Auburn University, AL 36849, USACeramatec, Inc., 2425 South 900 West, Salt Lake City, UT 84119, USACeramatec, Inc., 2425 South 900 West, Salt Lake City, UT 84119, USACenter for Microfibrous Materials, Department of Chemical Engineering, 212 Ross Hall, Auburn University, AL 36849, USAImpedance measurements were conducted under practical load conditions in solid oxide fuel cells of differing sizes. For a 2 cm2 button cell, impedance spectra data were separately measured for the anode, cathode, and total cell. Improved equivalent circuit models are proposed and applied to simulate each of measured impedance data. Circuit elements related to the chemical and physical processes have been added to the total-cell model to account for an extra relaxation process in the spectra not measured at either electrode. The processes to which elements are attributed have been deduced by varying cell temperature, load current, and hydrogen concentration. Spectra data were also obtained for a planar stack of five 61 cm2 cells and the individual cells therein, which were fitted to a simplified equivalent circuit model of the total button cell. Similar to the button cell, the planar cells and stack exhibit a pronounced low-frequency relaxation process, which has been attributed to concentration losses, that is, the combined effects of diffusion and gas conversion. The simplified total-cell model approximates well the dynamic behavior of the SOFC cells and the whole stack.http://dx.doi.org/10.4061/2011/465452 |
| spellingShingle | Robert U. Payne Ying Zhu Wenhua H. Zhu Mark S. Timper S. Elangovan Bruce J. Tatarchuk Diffusion and Gas Conversion Analysis of Solid Oxide Fuel Cells at Loads via AC Impedance International Journal of Electrochemistry |
| title | Diffusion and Gas Conversion Analysis of Solid Oxide Fuel Cells at Loads via AC Impedance |
| title_full | Diffusion and Gas Conversion Analysis of Solid Oxide Fuel Cells at Loads via AC Impedance |
| title_fullStr | Diffusion and Gas Conversion Analysis of Solid Oxide Fuel Cells at Loads via AC Impedance |
| title_full_unstemmed | Diffusion and Gas Conversion Analysis of Solid Oxide Fuel Cells at Loads via AC Impedance |
| title_short | Diffusion and Gas Conversion Analysis of Solid Oxide Fuel Cells at Loads via AC Impedance |
| title_sort | diffusion and gas conversion analysis of solid oxide fuel cells at loads via ac impedance |
| url | http://dx.doi.org/10.4061/2011/465452 |
| work_keys_str_mv | AT robertupayne diffusionandgasconversionanalysisofsolidoxidefuelcellsatloadsviaacimpedance AT yingzhu diffusionandgasconversionanalysisofsolidoxidefuelcellsatloadsviaacimpedance AT wenhuahzhu diffusionandgasconversionanalysisofsolidoxidefuelcellsatloadsviaacimpedance AT markstimper diffusionandgasconversionanalysisofsolidoxidefuelcellsatloadsviaacimpedance AT selangovan diffusionandgasconversionanalysisofsolidoxidefuelcellsatloadsviaacimpedance AT brucejtatarchuk diffusionandgasconversionanalysisofsolidoxidefuelcellsatloadsviaacimpedance |