Evaluation and Upscaling of Impregnated La 0.20 Sr 0.25 Ca 0.45 TiO 3 Fuel Electrodes for Solid Oxide Electrolysis Cells

Abstract

Recent research into Rh and Ce 0.80 Gd 0.20 O 1.90 -impregnated La 0.20 Sr 0.25 Ca 0.45 TiO 3 fuel electrodes for solid oxide fuel cells has demonstrated the high-stability of these material sets to a variety of harsh operating conditions at small scales (1 cm 2 active area button cells), as well as commercial scales (100 cm 2 cells) in short stacks (5 cells) and full micro-combined heat and power systems (60 cells). In this work, the authors present a comprehensive evaluation of the ability of these novel titanate-based materials to function as fuel electrodes in solid oxide electrolysis cells (SOECs). Short-term and durability testing of button cell scale SOECs highlighted the limited stability of lanthanum strontium manganite-based air electrodes, under CO 2 and steam electrolysis conditions, with lanthanum strontium cobaltite ferrite-based air electrodes offering improved degradation characteristics. Upscaling of this optimized cell chemistry to a 16 cm 2 active area SOEC and testing under CO 2 , CO 2 /H 2 O and H 2 O electrolysis conditions demonstrated encouraging performance over a period of ∼600 h, with stable co-electrolysis performance at ∼−7.5 A at 1.47 V for the first 100 h.