Next generation of reversible proton conducting ceramic cells and stacks for efficient energy applications at ≥1 kW scale

Expected Outcome:The growing global energy demand coupled with the concerns about environmental pollution necessitates an increased share of renewable energy sources, implementation of C-free fuels and electrification of energy intensive industry. This calls for developing an efficient reversible proton conducting ceramics (PCC) technology capable of producing hydrogen and operate with hydrogenated fuels to reduce operational downtime and benefit from sector coupling. A flexible solution can be implemented with the use of proton conducting ceramic cells, which can selectively extract hydrogen from various gas streams through proton transport in the dense electrolyte at intermediate temperatures ranging from 450 to 750 °C. For instance, electrochemical proton conducting ceramics (PCC) are investigated for reversible steam electrolysis and hydrogen fed fuel cells, ammonia fed fuel cell, ammonia cracking to hydrogen, CO2 conversion to chemicals, dehydrogenation of hydrocarbons. Extensive research at the single cell level for these applications is showing that PCCs can produce, extract, purify, electrochemically compress, and use hydrogenated molecules as feedstock for power and/or chemicals production. While PCC cells are investigated in many applications, limited studies have been conducted on assessing the techno-economic potential of this technology for reversible operation.There are several challenges to overcome to reach higher technological scales. The research work is primarily directed at cell level, which precludes the possibility for optimising thermal management. Reversible operation contributes to accelerated degradation in fuel cell mode, requiring more research on materials and cell assemblies, and their thermomechanical stability. In addition, there are challenges in developing reversible electrodes, which are equally active in both fuel cell and electrolysis modes. Improved electro-catalytic performance and faradaic efficiency have been observed when op