Anode-Supported Micro-SOFC Stacks Operated under Single-Chamber Conditions

Abstract

A micro solid oxide fuel cell (SOFC) stack with two series-wound single fuel cells was fabricated and operated successfully under single-chamber conditions. In this stack, the single cells were based on Ni/yttria-stabilized zirconia (YSZ) anode-supported YSZ membrane and were arranged with an anode-facing-cathode configuration in diluted methane and oxygen mixture gas between 600 and 750�C. The performances of the stack were affected by the flow rate, gas composition, and furnace temperature. The effects of the narrow path between two cells on the electrodes and cells were discussed in detail, according to the open-circuit voltages (OCVs) and impedance spectra of each cell. At 700�C, the maximum OCV of the whole stack was larger than 2.0 V at C H4 O2 =1.75 and 2, while the maximum power output of stack was about 371 mW at C H4 O2 =1 with a mass specific power of 552 mWg. The performance indicates that such microstacks have potential for portable applications. � 2007 The Electrochemical Society