LOW-TEMPERATURE, ANODE-SUPPORTED HIGH POWER DENSITY SOLID OXIDE FUEL CELLS WITH NANOSTRUCTURED ELECTRODES

Technical Report · Tue Mar 26 04:00:00 EST 2002

DOI:https://doi.org/10.2172/833840· OSTI ID:833840

Virkar, Anil V

Anode-supported cells comprising Ni + yttria-stabilized zirconia (YSZ) anode, thin ({approx}10 {micro}m) YSZ electrolyte, and composite cathodes containing a mixture of La{sub 0.8}Sr{sub 0.2}MnO{sub (3-{delta})} (LSM) and La{sub 0.9}Sr{sub 0.1}Ga{sub 0.8}Mg{sub 0.2}O{sub (3-{lambda})} (LSGM) were fabricated. The relative proportions of LSGM and LSM were varied between 30 wt.% LSGM + 70 wt.% LSM and 70 wt.% LSGM + 30 wt.% LSM, while the firing temperature was varied between 1000 and 1200 C. The cathode interlayer composition had a profound effect on cathode performance at 800 C with overpotentials ranging between 60 and 425 mV at 1.0 A/cm{sup 2} and exhibiting a minimum for 50 wt.% LSGM + 50 wt.% LSM. The cathodic overpotential decreased with increasing firing temperature of the composite interlayer in the range 1000 {le} T {le} 1150 C, and then increased dramatically for the interlayer fired at 1200 C. The cell with the optimized cathode interlayer of 50 wt.% LSM + 50 wt.% LSGM fired at 1150 C exhibited an area specific cell resistance of 0.18 {Omega}cm{sup 2} and a maximum power density of 1.4 W/cm{sup 2} at 800 C. Chemical analysis revealed that LSGM reacts with YSZ above 1000 C to form the pyrochlore phase, La{sub 2}Zr{sub 2}O{sub 7}. The formation of the pyrochlore phase at the interface between the LSGM/LSM composite cathode and the YSZ electrolyte limits the firing time and temperature of the cathode interlayer.

• Research Organization: University of Utah (US)
• Sponsoring Organization: (US)
• DOE Contract Number: AC26-99FT40713
• OSTI ID: 833840
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
CATHODES
CHEMICAL ANALYSIS
ELECTRODES
ELECTROLYTES
MIXTURES
PERFORMANCE
POWER DENSITY
PYROCHLORE
SOLID OXIDE FUEL CELLS