Single cell and stack structure for solid oxide fuel cell stacks

摘要

A single cell and stack structure for SOFC stacks is disclosed. The single cell (4) consists of a fuel electrode, an electrolyte and an air electrode, with opposite two or four sides of said single cell is shaped while being bent downwardly, thus forming an electrode support type structure or a self-support (electrolyte support) type structure each having a reversed U-shaped cross-section. In the SOFC stack structure, electrode support type or self-support type single cells (4) are gastightly stacked on a separating plate (9) while being held on a plurality of sealing grooves (12) sealed with sealant. In the SOFC stack, the fuel gas and the oxidizing gas are free from being mixed together due to an improved gas sealing structure. The SOFC stack is thus free from a stress due to a difference in coefficient of thermal expansion between the single cells and the separating plate at a raised or lowered temperature. When the SOFC stack is assembled, the bent support portions of the single cells are precisely seated in the sealing grooves of the separating plate. The single cells are thus stably held within the SOFC stack while lengthening the expected life span of the stack, improving the durability and the operational reliability of the stack, and allowing a user to more easily repair the stack when necessary.