Survey of Types of Solid Electrolytes
This chapter provides different types of solid electrolytes. Solid electrolytes are a class of materials exhibiting high ionic conductivity like electrolyte solutions, though they are in the solid state. In general, the fluoride ion is thought to be more mobile in the solid state than the oxide ion because it is monovalent and its radius is smaller. Solid proton conductors are of great importance in relation to the development of fuel cells, sensors, and electrochromic devices. Members of the low- or moderate-temperature-type group are some solid state acids and the family of β-aluminas ion exchanged with protons. The high-temperature group consists of oxides belonging to the perovskite family. Some vinyl fluoride-based polymers with side chains of perfluorosulfonic acid are important ion-exchange membrane materials used in practice for electrolysis of NaCl and in certain fuel cells.