Investigation of Internal Reforming Reaction at Low Temperature Using Micro Tubular Solid Oxide Fuel Cell

Abstract

Internal reforming reaction at low temperature in micro tubular solid oxide fuel cell (SOFC) was investigated by electrochemical impedance spectroscopy and numerical simulation using FLUENT. A micro tubular cell was composed of NiO/(ZrO₂)_0.9(Y₂O₃)_0.1 anode-substrate, La_0.8Sr_0.2Ga_0.8Mg_0.2O_2.8 electrolyte, and La_0.6Sr_0.4Co_0.2Fe_0.8O₃ cathode. It was suggested that cell performance became lower in supplied 50% reforming gas composition at 873 K because of variation of current density and hydrogen partial pressure distribution along the cell axis direction. The reason was that steam reforming reaction rate was slow along the cell axis direction and shift reaction occurred mainly without CO electrochemical oxidation owing to heat radiation of the cell at lower temperature.