Optimization of ESC performance for co-electrolysis operation

Production of synthetic hydrocarbon fuels from co-electrolysis of steam/CO2 mixtures using renewable energy has been already presented as a promising solution to diminish environmental problems. The possibility to recycle CO2 into chemicals and value-added fuels helps to reduce the accumulation of atmospheric CO2 and realize the carbon neutral cycling of fuels. While the co-electrolysis is more complicated than steam electrolysis, the electrochemical performance of electrolyte supported cell with LSMM'/ScSZ and Ni/GDC electrodes was investigated over a wide range of operating conditions (SOEC as well as SOFC), varying the ratio of H2O:H2 and CO2:CO, the operating temperature (750-850°C) and current. The modified standard SOFC cell with optimized fuel and air electrodes was successfully tested for ∼2400 hours at 803°C under co-electrolysis conditions (H2/H2O/CO2/CO mixture as fuel, j = -400 mA/cm2). The calculated linear power degradation rate over all durability test (∼2400 h) is about 0.4%/1,000 h.