Glass foils as sealing elements in SOFC stacks

Two crystallizing glasses of the basis of an alkaline earth borosilicate glass were developed. The glasses are suitable for sealing stacks with CrFe5 and ferritic steel interconnectors. In the crystallized glasses different crystal phases are present, which determine substantially the properties particular the thermal expansion coefficient. By tape casting green foils were manufactured from these glasses. From green foil pieces the sealing parts were punched out. The shrinkage behavior of the green foils must be considered to avoid leakages in the sealing frame. With sealing elements from both glasses stacks with up to 60 single cells were sealed successfully.