Effect of Anode Side Purge Gas on the Degradation of Solid Oxide Electrolysis Cells

Abstract

Solid oxide electrolysis cells (SOECs) has drawn great interest in recent years due to its high power to fuel efficiency. The technology is believed to be able to play an important role in the power-to-x (P2X) and carbon capture and utilization (CCU) applications due to its capability of CO2 electrolysis and H2O + CO2 co-electrolysis. The syngas produced from SOEC can be further catalytic converted into different higher value synthetic fuels, which is essential for the green transition of those hard-to-be-electrified sectors such as aviation and heavy transportation. Large-scale implementation of such a technology requires SOEC to be cost competitive with the current existing electrolysis technologies. High performance and long-term durability are keys to further bring down the SOEC fuel production costs. Understanding the degradation mechanisms and identifying limits for a “safe-operation-window” for which the degree of degradation is limited will help to further advance the SOEC technology to the market. In this work, the influence of operation parameters such as temperature, gas composition and reactant utilization on the SOECs’ degradation were examined with commercial solid oxide cells from Elcogen. The degradation mechanisms investigated by electrochemical impedance and post-test microstructure analysis will be presented and discussed.This work has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 838014 (C2FUEL).