Development of Modelling and Testing for Analysis of Degradation in Solid Oxide Fuel Cells

The ability to predict the lifetime performance of an SOFC can give guidelines for where improvements and alterations can be made in terms of production, operating parameters and cell design.  Multiple attempts have been made to implement models which can respond to all the varying parameters to give their characteristic performances over longer operational lifetimes than is feasible to physically test.

This study focuses on continuous degradation mechanisms and the impact they have on the components of a single repeating unit level, i.e. the anode, cathode, electrolyte, metal interconnect and sealants. Currently the model being developed deals specifically with anode and electrolyte degradation. Depending on operating conditions, SOFC cells suffer from Ni particle agglomeration, coarsening, and volatilisation which lead to increased overpotential in the anode. A loss in the ionic conductivity in the electrolyte is also observed.

Using models derived for these degradation mechanisms combined with percolation models, Matlab ® coding has been developed to outline the loss of performance in a single repeating unit for a given set of operating parameters. These equations will be tested against real life data to establish their validity and, where necessary, adjusted for accuracy.  Further progress will allow for accelerated testing of components and cells to determine the long term performance of a given material alteration or design change.