Development of Portable SOFC System Using Microtubular Cells

Abstract

The effect of operating temperature on durability was investigated for direct butane utilization in anode-supported microtubular solid oxide fuel cells (SOFCs). At 710 oC, the performance of the Ni-Gd-doped ceria (Ni-GDC) anode deteriorated rapidly for less than 2 h at a relatively low steam/carbon (S/C) ratio of 0.044 in butane, because a large amount of carbon was deposited on the anode by butane cracking. On the other hand, the electric power could be generated continuously for more than 24 h at 610 oC and S/C = 0.044 in butane for the cell using the Ni-GDC anode. Lowering the operating temperature realized high durability against carbon deposition on the Ni-GDC anode under the direct butane utilization. We manufactured and demonstrated a prototype portable SOFC system using a microtubular cell-stack. It can be heated up to 400 oC within 2 minutes by burning an LPG burner, and drive a USB device for 24 h continuously using a LPG cartridge (250 g; 3.2 kWh). This development has shown the potential of the microtubular SOFC system as portable power sources in disaster and emergency situations, for outdoor use, and for small-scale electric vehicles.