Development of novel electrolyte and anode materials for intermediate temperature solid oxide fuel cell

Abstract

Solid oxide fuel cells (SOFC) are energy conversion devices by transforming the chemical energy of fuel into more usable electrical energy at high temperatures. Their higher efficiency and fuel flexibility make them a promising candidate for energy production in various fields. However, the new materials should be developed in order to decrease the material cost and lower the operating temperatures of SOFC systems. SOFC system consists of three main components, an anode, electrolyte and cathode. This study mainly focuses on manufacturing novel electrolyte and anode materials for SOFC. The potential electrolyte material, 20 % Gadolinium doped Ceria (GDC) has higher ionic conductivity compared to conventional electrolyte material 8 % Yttria stabilized Zirconia (YSZ), but GDC has relatively higher electrical conductivity which is undesirable for an electrolyte material. Doping GDC with other metals can improve its properties as an electrolyte or an anode. In this study, Titanium, Vanadium and Manganese is doped to GDC and also Vanadium is doped to Ceria only. According to Four Probe measurements and EIS (Electrochemical Impedance Spectroscopy), 1 % Vanadium doped Ceria has higher ionic and lower electrical conductivity values so that it can be used as an electrolyte for an intermediate temperature SOFC. Additional study was on impregnation of Vanadium and Manganese metals on the anode side of the commercial Nickel-YSZ (Ni-YSZ) anode, YSZ electrolyte, and Lantanum Strontium Manganese (LSM) cathode fuel cells. Power density of the fuel cell increased 25 % after Vanadium impregnation, and the power density increased 145 % increased after Manganese impregnation. Manganese impregnation on the anode side has a significant impact on the performance of a SOFC.