Stack-like Contacting in Solid Oxide Cells: Electrochemical Characterization and Modeling

In this contribution, a Crofer 22 APU$^®$ interconnector with a $\textrm{(Mn, Co, Fe)}_{3}\textrm{O}_{4}$ spinel oxide (MCO) coating and a lanthanum-strontium-manganese-cobalt oxide (LSMC) contact layer at the air side was investigated. The electrochemical behavior was characterized by means of IV-characteristics, impedance spectroscopy and DRT analysis.

In particular, the contact losses at the air side were measured with targeted potential probes. With respect to the contact layer mounted in a dried state, the application of a stack-like clamping pressure of 1 MPa showed a significant decrease of the contact resistance. In order to extend an existing zero-dimensional performance model for an electrolyte-supported cell with a Ni/GDC fuel electrode and LSCF air electrode, a method was established to parameterize contact losses at the air electrode.