Optimization of Processing and Structural Parameters of Lanthanum Strontium Manganate-based Cathodes

Lanthanum strontium manganate (LSM)-based cathodes, (La_0.8Sr_0.2)_0.9MnO_3-δ with A-site deficiency, were prepared by the conventional solid-state reaction. The effects of several factors, including defect structure, mass ratio of LSM and YSZ, pore structure characteristics and charge collection methods of the lanthanum strontium manganate-yttria-stabilized zirconia (LSM-YSZ) composite electrode, on performance of the anode-supported solid oxide fuel cells (SOFCs), were studied. It was found that the LSM with 10% A-site deficiency has higher performance than the stoichiometric LSM. The cathode slurry with polyvinyl butyral (PVB) as the binder has better pore structure. The optimal weight ratio of LSM to YSZ is 6:4, with optimized porosity of 28%. The cathode performance could be effectively improved by coating an LSM current collection layer on the LSM-YSZ layer, while the optimized porosity of the LSM current collection layer is 42%. Under the optimal conditions, a peak power density of 780 mW·cm^-2 was achieved at 800 ℃.