Solid Ionic Conductors: Principles and Applications

Solid ionic conductors, also called solid electrolytes, transport electric current by means of ions. The best known examples of these usually crystalline compounds include doped ZrO 2 , as well as AgI, β‐Al 2 O 3 , and CaF 2 . Ionic conduction in solid electrolytes reaches its maximum value if a partial lattice of a solid compound undergoes transition at elevated temperature to a quasimolten state. The ionic conductivity in such solid compounds is then as high as in molten salts. Solid electrolytes have found many scientific and technological applications; thus, they can be used to study thermodynamic and kinetic problems, and to build fuel cells, batteries, sensors, and chemotronic components.