Research Of Novel Glass Ceramic Composite Seals For Solid Oxide Fuel Cell

Intermediate temperature planer Solid Oxide Fuel Cell （IT-SOFC） quickly catches theresearchers’ eyes around the world due to its high power density and easy fabrication.However, one of the biggest challenges for the development of IT-SOFC is the sealingproblem. In this paper, new Al₂O₃based seals and glass based seals were fabricated basedon the advantages of Al₂O₃-Al composite seals and glass seals prepared in earlier researchand were tested and analyzed thereafter.For Al₂O₃based composite seals, the changes of leakage rates were not various whena small amount of glass powder was added into the seals, but significant changes wereobserved when doped more glass powder, which was because that the melted and softenedglass would block the pores to prevent gas leakage at high temperature. However, with theincrease of thermal cycles and the added glass powder, the crystallization would aggravateand then the seals would crack quickly.The leakage rates of the glass based seals which were added30%Al₂O₃（named asHGS1） were extremely low and even after25thermal cycles the leakage rates were stillbelow0.01sccm.cm^-1within the SECA standard. The new phases and closed pores causedby the reaction of glass and Al₂O₃had produced no various influences on the leakage rates.Good compatibility between seals and the adjacent components provided well interfacecontact and when the seal was applied for single cell testing, undetectable degradation ofthe voltage clearly demonstrated the applicable performance of HGS1seal in solid oxidefuel cell.Compared with these two seals, the overall performance of HGS1seals were betterthan Al₂O₃based composite seals indicating large commercial potential.