Evaluation and upscaling of impregnated La_0.20Sr_0.25Ca_0.45TiO₃ fuel electrodes for solid oxide electrolysis cells

Recent research into Rh and Ce_0.80Gd_0.20O_1.90-impregnated La_0.20Sr_0.25Ca_0.45TiO₃ 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 cm² active area button cells), as well as commercial scales (100 cm² 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 CO₂ 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 cm² active area SOEC and testing under CO₂, CO₂/H₂O and H₂O 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.