Structure investigations of SOFC anode cermets - Part II: Electrochemical and mass transport properties

An approximate description of the SOFC cermet structure was performed on the basis of a combined optical and porosimetric structure analysis of the SOFC cermet anode and the results are described using the example of the SOFC substrate anode (anode with increased layer thickness). The electrode assembly consists of two layers. The electrochemically active layer of 70-90 mu m corresponding the penetration depth of the electric field is located near the ZrO(2) electrolyte. This layer thickness is also a function of porosity and pore radius distribution. The remaining electrode up to a layer thickness of about 2 mm basically acts only as a current and mass distributor. The corresponding diffusion overvoltage as a function of the structural properties was calculated.