Final Report Summary - HI2H2 (Highly efficient, High temperature, Hydrogen Production by Water Electrolysis)
The HI2H2 project objective was to utilise the materials and technological developments of planar solid oxide fuel cell (SOFC) technology in order to develop a planar solid oxide electrochemical converter (SOEC) for hydrogen production by water electrolysis. The project aimed to demonstrate SOEC degradation inferior to 1 % per 1 000 hours on a short 25cm2 stack for a period of 2 000 hours.
The necessary electrode and metal supported cells were developed based on SOFC cells. Improved metal coatings, anode and cathode materials were also designed. The proposals were evaluated through a series of electrolysis tests with very promising results. The developed SOECs appeared to have optimum initial performance in comparison to other alternatives under similar operation conditions.
Moreover, two different protective layer options were selected for the interconnection of SOEC material compounds and were characterised under various conditions. The passivation and activation phenomenon that was observed during SOEC development was attributed to silicate depositing on the interface between the electrolyte and the H2 electrode. The identified silica quantities were probably caused by the glass seal of the cells.
The necessary electrode and metal supported cells were developed based on SOFC cells. Improved metal coatings, anode and cathode materials were also designed. The proposals were evaluated through a series of electrolysis tests with very promising results. The developed SOECs appeared to have optimum initial performance in comparison to other alternatives under similar operation conditions.
Moreover, two different protective layer options were selected for the interconnection of SOEC material compounds and were characterised under various conditions. The passivation and activation phenomenon that was observed during SOEC development was attributed to silicate depositing on the interface between the electrolyte and the H2 electrode. The identified silica quantities were probably caused by the glass seal of the cells.
