High-temperature electrolysis (SOEC)

One of the most promising technologies for the production and utilisation of hydrogen is the solid oxide cell (SOC). The ceramic high-temperature solid oxide cell (SOC) can be operated in electrolysis mode (solid oxide electrolyzer cell, SOEC), in fuel cell mode (solid oxide fuel cell, SOFC) and in reversible mode (rSOC). Requirements resulting from the increasing importance of renewable energies are favouring the integration of bi-functional reactors, which operate alternately in electrolysis and fuel cell mode and can therefore avoid thermal cycles or interruptions in operation when they are switched between modes. The advantages of bi-functional systems are higher utilisation and lower investment costs compared to conventional systems. In addition, fuel cell operation is characterised by a large variability of hydrogen-containing fuels and a comparatively high robustness against impurities in the fuel gas. Based on the existing SOC technology, reliable and efficient bi-functional SOC cells and cell stacks are to be investigated and further developed with regard to performance and ageing in reversible operation.

Forschungszentrum Jülich has more than 30 years of experience in the development of SOCs, covering the entire spectrum from raw materials to complete systems. Interdisciplinary teams have been working together for years on the research and development of new materials, processes, test methods, stacks and systems.

One of the biggest challenges for the success of the SOC is a robust joining material to integrate the ceramic cell into the stack. The ZEA-1 specialises in the development of glass-ceramic joining materials tailored to the individual joining partners (ceramic/steel). The existing infrastructure enables innovative compositions to be melted and characterised in close relation to the application.

In addition, the development of high-performance, cost-effective stack designs suitable for series production is a substantial contribution of the ZEA-1.