Fabrication of multi-layered structures for proton conducting ceramic cells

Protonic ceramic fuel cells offer a high potential to produce electrical energy in a very efficient way. The performance of such a device among others is highly dependent on the electrolyte material and its thickness. Therefore, multilayer structures are used to reduce the electrolyte thickness down to 10-20 mu m, supported by a much thicker porous anode. In this work sequential tape-casting is used to fabricate half-cells consisting of a BZCY electrolyte and a BZCY/NiO support which also serves as the anode layer. The starting powders are characterised as well as the thermal behaviour of the half-cells during heat treatment. Sintering experiments show that a temperature of T >= 1450 degrees C is needed to achieve the desired microstructure. After that a scale-up approach to a size of the half-cells of about 25 cm(2) is shown. The influence of the processing temperature on the microstructure is shown by detailed XRD and SEM studies. The formation of a BaY2NiO5 transient liquid phase during the heat treatment of the cells is clearly demonstrated. Finally, the proton conductivity of the tape-cast cells shows competitive values of sigma = 0.003 S cm(-1) at 600 degrees C with the advantage of an industrially proven and up-scalable manufacturing technique.

Automated summary

Protonic ceramic fuel cells show high potential for efficient energy production, with multilayer structures used to optimize electrolyte thickness and performance. The study demonstrates the fabrication process of cells using sequential tape-casting, with detailed characterization of starting powders and thermal behavior during heat treatment. The research also reveals the formation of a BaY2NiO5 transient liquid phase during cell heat treatment, showcasing competitive proton conductivity values at 600 degrees C.