Electrochemical Performance of Planar Solid Oxide Fuel Cell (SOFC) Stacks: From Repeat Unit to Module

The electrochemical performance of a solid oxide fuel cell (SOFC) manufactured stack module (MSM) subjected to thermal cycling sintering is generally lower than that of a unit cell tested directly. By characterizing a 10-cell stack assembled from a 5-cell testing stack and a 5-cell manufactured short stack module, the main factors that affect the electrochemical performance were determined to be the contact uniformity and depth between the interconnect and cell cathode covering the total surface. The cathode contact is improved by designing the external pressure on the stack during the manufacturing process; thus, the output power of a 30-cell MSM from a typical type of anode made from yttria-stabilized zirconia (YSZ) and lanthanum strontium manganite (LSM), Ni-YSZ/YSZ/LSM, for which the cell reached approximately 750 W power at the working temperature of 800 degrees C. Futhermore, the 30-cell MSM shows no degradation during the experiment. The electrochemical performance (herein referring to output power density and operating stability) approaches that of the corresponding unit cell being tested directly