(Invited) Studies on Fabrication Process Cost Reduction for LT-/IT-SOFCs

Abstract

Solid oxide fuel cells (SOFCs) have attracted many attentions as a next-generation energy conversion device because of their high efficiency and the ability to use a variety of fuels. However, conventional manufacturing processes cause high manufacturing cost and therefore impedes commercialization of SOFCs. SOFC components are mainly produced by non-vacuum powder based process to improve productivity. To achieve desired material properties high-temperature post-heat treatment process usually above 1400oC is required for a long time for ceramic electrolyte and electrode fabrication. This long and high temperature sintering process significantly increases production costs and becomes a hurdle for widespread usage. Therefore, in order to reduce the manufacturing cost of the SOFCs, it is essential to improve the fabrication process especially the high temperature sintering process. Accordingly, to lower the high sintering temperature, a bilayer sintering process using a sintering aid was designed, and it successfully lower the sintering temperature while maintaining the material properties. The fabricated YSZ electrolyte by the developed low temperature sintering process showed a relatively high performance. In addition, through the applying an innovative flash light sintering process, the rapid sintering process of powder based ceramic electrolyte and electrode are successfully demonstrated for the first time. Therefore, a long process time of several tens of hours in thermal sintering process can be significantly reduced within tens of seconds through the development of flash light sintering process.