Model Based Comparative Analysis of GDC and YSZ Based Solid Oxide Fuel Cells

Abstract

Although solid oxide fuel cells (SOFC) offer high fuel-to-electric energy conversion efficiencies, their relatively low power-to-weight ratios make it difficult to integrate them with aircraft propulsion systems. This paper explores the feasibility of designing high throughput SOFCs for hybridization with gas turbines in aircraft powerplants. This paper explores and compares two SOFC technologies for achieving high specific power (kW/kg) with different membrane electrode assembly architectures, one with thin-film yttria-stabilized zirconia (YSZ) electrolytes and the second with high-power density gadolinia doped-ceria (GDC) electrolytes. The studies explore the operation of the respective SOFC stacks with synthetic CH4 as a carbon-neutral aviation fuel. Down-the-channel SOFC models are calibrated to experimental measurements of YSZ- and GDC-electrolyte cells at Elcogen and at the University of Maryland respectively. The model results provide a basis for determining the flow inlet conditions that enable each cell type to achieve high specific powers. The results also indicate the requirement of high airflows and upstream fuel preprocessing to sustain the high specific powers with sustainable cell operating conditions.