Characterisation and optimisation of the cathode/electrolyte couple for SOFC LSCF/BIT07

• Published in: Journal of power sources Vol. 212; pp. 161 - 168
• Main Authors: Letilly, Marika, Joubert, Olivier, Le Gal La Salle, Annie
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.08.2012; Elsevier
• Subjects: Ageing; Applied sciences; BIT07; Direct energy conversion and energy accumulation; EIS; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel cells; LSCF; Materials; Optimisation; SOFC; BIT07; LSCF; Optimisation; Ageing; EIS; SOFC; Performance evaluation; Cobalt oxide; Grain size analysis; Iron oxide; Perovskite type compound; New product; Cathode; Electrode material; Solid oxide fuel cell; Optimization; Lanthanum oxide; Thickness; Ferrites; Time varying system; Electrolyte; Microstructure; Strontium oxide
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2012.03.042

BaIn0.3Ti0.7O2.85 (BIT07) is a new electrolyte material for solid oxide fuel cells (SOFC). Its use with the cathode material La0.58Sr0.4Co0.2Fe0.8O3−δ (LSCF) is advantageous due to their reaction (above 1000°C) that leads to the formation of perovskite compounds called BLSITCFx (BaxLa0.58(1−x)Sr0.4(1−x)In0.3xTi0.7xCo0.2(1−x)Fe0.8(1−x)O3−δ, with 0≤x≤1) at the cathode/electrolyte interface. In this study, the influence of the cathode microstructure on its performance has been investigated, by varying the cathode parameters. An area specific resistance (ASR) value of 0.07Ωcm2 at 700°C has been reached and more generally the cathodes exhibit good performance (below 0.2Ωcm2) for a large range of thermal treatments, cathode grain sizes and thicknesses. An ageing study realised at 700°C for 320h showed an ageing rate of 0.125%h−1. ► Mechanical and chemical characterisations of an LSCF/BIT07 assembly. ► Optimisation of the half cell performance by a design of experiments. ► Study of the half cell ageing behaviour