The recent progress of planar solid oxide fuel cell stack

Solid Oxide Fuel Cells (SOFCs) represent an attractive technology for the conversion of chemical to electrical energy because of their high efficiencies and low environmental impact. Additionally, they also have good fuel flexibility and long-term stability, which could direct utilize the hydrocarbon fuels and contribute to the more sparing utilisation of remaining fossil fuel reserves. Thus, they have been regarded as one of the most promising green power generation system in the near future. SOFC stacks are the key components of SOFC power generation system. Planar SOFC stack fabricated by assembling the planar single cells in series have the advantages of short current route and thereby of the low ohmic cell resistance, high power density and performance, simple structure, relatively easy fabrication process and low cost. However, it still has drawbacks of difficult sealing technique, low thermal cycle stability and high performance degradation. In this paper, the recent progress of the research and development on planar SOFC single cells and stacks are comprehensively reviewed, including the materials and structures of single cells, sealing strategy and types of sealants, design and materials of interconnects and the design and assembly of the stacks. The state of the art technologies and the current achievements of the companies and institutes which take the lead in SOFC field are introduced as well. Finally, some key issues need to be addressed for promoting the commercialization processes of planar SOFC stacks are put forward.