Efficient planar SOFC technology for a portable power generator
Portable power generators for camping and industrial applications require start-up times around 30 minutes and need to achieve a life time of 3,000 h including 300 cycles. Preferably they operate on available fuels and have a compact and lightweight system design. Eneramic®, a portable solid oxide fuel cell (SOFC) system in the 100 Watt class has been developed. A planar SOFC stack based on electrolyte supported cells and ferritic interconnects is used for the eneramic® system. The long-term stability of SOFC stacks was tested over more than 3,000 hours with power degradation below 1.0 %/1,000 h. However, hotbox testing of 40-cell stacks and stack operation in the system environment revealed slightly higher degradation rates between 2.1 and 2.3 %/1,000 hours. SOFC stacks exposed to thermal cycles showed no power losses. The results show that the compact planar SOFC stack is capable to survive the expected system life time.