Li ion conduction in LiLnSiO₄ (Ln = La, Nd, Sm, Eu, Gd and Dy) sinters

Electrochemical properties of hexagonal lithium lanthanoid silicates were investigated to confirm their lithium ion conduction at elevated temperatures. EMF of oxygen concentration cells using the specimen as an electrolyte obeyed Nernst's equation, indicating their unique ionic conduction. The charge carrier for the ionic conduction was confirmed quantitatively to be lithium ions by means of Tubandt's method. Partial substitution of alkaline earth metals and lithium for lanthanum in LiLaSiO₄ was found to be effective to enhance conductivity and to improve sintering property.