IONIC-CONDUCTION OF LITHIUM FOR PEROVSKITE-TYPE COMPOUNDS, LIXLA(1-X)3NBO3 AND (LI0.25LA0.25)(1-X)SR0.5XNBO3/

Perovskite-type compounds, LixLa(1-x/3)NbO3 and (Li0.25La0.25)(1-x)Sr0 .5xNbO3 as lithium ionic conductors, were synthesized by a solid-state reaction. From powder X-ray diffraction, the solid solution ranges of the two compounds were determined to be 0 less than or equal to x les s than or equal to 0.25 and 0 less than or equal to x less than or equ al to 0.125, respectively. In the LixLa(1-x/3)NbO3 system, the ionic c onductivity of lithium at room temperature, sigma(25), exhibited a max imum value of 4.7 x 10(-5) S . cm(-1) at x = 0.10. However, because of the decrease in the lattice parameters with increasing Li concentrati on (x) over dot, sigma(25) Of the samples decreased with increasing x from 0.10 to 0.25. Also, in the (Li0.25La0.25)(1-x)Sr0.5xNbO3 system, the lattice parameter increased with the increase of Sr concentration and the sigma(25) achieved a maximum (7.3 x 10(-5) S . cm(-1) at 25 de grees C) at x = 0.125.