18
Lanthanum-Gallate-Based
Composite Cathodes for Anode-Supported, Intermediate Temperature (600-800ēC)
Solid Oxide Fuel Cells--Materials
and Systems Research, Inc., 5395 West 700 South,
Dr.
Tad J. Armstrong, Principal Investigator, tarmstro@msrihome.com
Dr.
Dinesh K. Shetty, Business Official, dshetty@msrihome.com
DOE
Grant No. DE-FG02-3ER83871
Amount:
$499,268
Increasing
the power density of solid oxide fuel cells (SOFC) can substantially
reduce the costs of SOFC technology by decreasing the stack size, which in turn
decreases the amount of materials necessary, reduces the size of the balance of
plant, and decreases the size and amount of requisite stack hardware and
insulation. Likewise, lowering the
operating temperature of SOFC lowers costs due
to higher operating efficiency and the use of inexpensive metallic
materials, less thermal insulation, and simplified heat management.
This project will develop an anode-supported,
thin-film YSZ electrolyte SOFC with composite cathodes comprised of the ionic
conductor Lanthanum-Gallate (LSGM) and an electrocatalyst.
Because LSGM exhibits high oxide ion conductivity (higher than YSZ), it
can substantially lower the overpotential at the cathode and thus increase the
power density of the SOFC. In
addition, the thin-film YSZ electrolyte (~5 microns) and the LSGM-based
composite cathode would enable the SOFC to operate at lower temperatures
(600-650°C).
In Phase I, anode-supported SOFC
with thin-film YSZ electrolytes and composite cathodes (comprised of the ionic
conductor LSGM and electrocatalysts LSM, LSC, and LSCF) were developed,
fabricated, and tested. Exceptionally
low cathode overpotentials, which resulted in significant increases in SOFC
performance, were demonstrated with the use of LSGM-based composite cathodes.
Phase II will identify other electrocatalysts for use with LSGM, dope the
LSGM to further improve
ionic conductivity, and synthesize nanosize powders in order to engineer the
desired cathode microstructure.