FES Funded ProjectsOutputs
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The Effect of Pore-Former Morphology on the Electrochemical Performance of Solid Oxide Fuel Cells under Combined Fuel Cell and Electrolysis ModesThis paper discusses a critical aspect of fabricating high temperature fuel cell/electrolysis cells - the amount and morphology of the pore former added to the electrodes prior to sintering that is used to create porosity to minimize both activation and concentration polarization. Fine spherical polymethyl methacrylate (PMMA) proved superior to angular somewhat coarser graphite. The fine pore structure decreased activation polarization by increasing the triple phase boundary length but still provided sufficient porosity for unrestricted gas flow. Most importantly, reversibility experiments (alternating between fuel cell and electrolysis modes) showed no degradation in performance for over 400 h.T06-P04 University of Alberta | Publication | 2018-04-24 | "Miguel A. Laguna-Bercero, A Laguna-Bercero, Miguel, Hanifi, A., "Lucile Manard ", Navjot K Sandhu, Neil E Anderson, Thomas Etsell, "Partha Sarkar " | High Performance Tubular Solid Oxide Fuel Cell based on Ba0.5Sr0.5Ce0.6Zr0.2Gd0.1Y0.1O3-d Proton Conductor ElectrolyteProton conducting electrolytes vs. oxygen ion conducting electrolytes have a major advantage in high temperature fuel cell/electrolysis cells - the fuel is not diluted as the cell is operated since water or CO2 is present at the air side rather than the fuel side. This novel composition was used to fabricate a tubular cell by a combination of slip casting and dip coating. Contrary to virtually all proton conductors, it appears chemically inert to both H2O vapour and CO2 as well as the other cell components. Correspondingly, it gave outstanding electrochemical performance producing a power output of 1 W/cm2 at 850C. This is among the highest output ever reported for a tubular cell with either a proton or oxygen ion conducting electrolyte. Electrochemical impedance spectroscopy was used in an effort to separate the various polarization losses.T06-P04, T02-C01 University of Alberta | Publication | 2018-04-24 | Taghi Amiri, "Kalpana Singh ", Hanifi, A., Thomas Etsell, Luo, J., "Venkataraman Thangadurai ", "Partha Sarkar " | Development of a Novel Proton Conducting Fuel Cell based on a Ni-YSZ SupportOne of the chief disadvantages of proton conducting fuel cells (and electrolytic cells) is a typical problem when ceramic materials are involved - poor mechanical properties. Robust oxygen ion conducting tubular cells have been fabricated with the Ni-yttria stabilized zirconia (YSZ) composite as the cell support (serves also as one of the electrodes). Not only does YSZ provide reasonable ionic conductivity and excellent chemical inertness but it is one of the best ceramic materials with respect to fracture toughness. This success has been capitalized on by using Ni-YSZ as the support for a tubular proton conducting cell. Reasonable power outputs from 600-700C were obtained. This could greatly increase the longevity and decrease fabrication costs of proton conducting cells. T06-P04 University of Alberta | Publication | 2018-04-24 | Hanifi, A., Navjot K Sandhu, Thomas Etsell, "Partha Sarkar " | Tetragonal Zirconia as Next Generation Support for Dry Reforming Solid Oxide Fuel CellThe usual structural support for ceramic fuel cells is nickel plus fully stabilized cubic zirconia containing 8 mol % Y2O3. This is the electrolyte composition as well. It has very good mechanical properties (at least relative to most ceramics). However, partially stabilized two-phase zirconia (tetragonal + cubic) containing 3 mol % Y2O3 has excellent mechanical properties due to monoclinic-to-tetragonal transformation toughening. Also, when mixed with nickel (the support also serves as one of the electrodes), it appears to slow down nickel agglomeration with an attendant loss of electronic conductivity. However, it has lower ionic conductivity that impacts the amount of triple phase interface (gas, electrode, electrolyte) available for electrochemical reaction. Preliminary results under syngas with the new support composition resulted in comparable, if not better, power outputT06-P04 University of Alberta | Activity | 2017-10-24 | | Microstructure and Long Term Stability of Ni-YSZ Anode Supported Fuel Cells: A ReviewA comprehensive review article focused on the importance that stability measurements be included in research papers as they are ultimately much more important than the initial electrolytic or fuel cell behaviour. Degradation issues is the main technical reason limiting widespread commercialization of SOEC/SOFCs.T06-P04 University of Alberta | Publication | 2021-05-12 | Sajad Vafaeenezhad, Hanifi, A., Miguel A Laguna-Bercero, Thomas Etsell, "Partha Sarkar " |
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