Fuel cells - Solid oxide fuel cells membranes

The high-temperature membranes or membrane-electrode assemblies (MEAs) for solid oxide fuel cells consist of a thin electrolyte with a high ionic conductivity, a perovskite cathode, and a cermet anode. Different types of MEAs are currently under development: electrolyte-supported cells, anode-supported cells, or metal-supported cells. The most commonly used electrolyte material for cell manufacturing is doped zirconia. The ionic conductivity of membranes consist of doped zirconia and the factors that influence their stability are comprehensively described in this article. The short overview of alternative electrolytes and electrode materials and their interaction with electrolytes as well as the stability of electrochemically active interfaces is given. The area specific resistance (ASR) of the cell depends strongly on the polarization resistance of the electrodes and the art and the thickness of electrolyte used. The costs of single cell, as well as ASR, should be reduced to obtain high power density and efficiency and to reduce the specific costs (in ekWel-1). The cost-effective manufacturing processes for tubular and planar cells are described and both cell types are compared.