Limitations in the use of solid state electrochemical cells for high-temperature equilibrium measurements

The major factors which limit the successful application of solid-state electrochemical cells in high-temperature equilibrium measurements are summarized. Such factors include electronic conduction in the solid electrolyte, difficulties in maintaining a fixed chemical potential at the electrode-electrolyte interface, and general experimental uncertainties. Particular attention is directed towards cells using ZrO₂-based and ThO₂-based solid electrolytes. Whenever possible, examples from the literature are used to illustrate particular points.