SOLID-STATE CATHODE MATERIALS FOR LITHIUM BATTERIES - EFFECT OF SYNTHESIS TEMPERATURE ON THE PHYSICAL AND ELECTROCHEMICAL PROPERTIES OF SILVER VANADIUM-OXIDE

Silver vanadium oxide (SVO, AgV2O5.5) was synthesized for use as a cat hode material in lithium/SVO batteries. The material was prepared via a solid-state thermal reaction of silver nitrate and vanadium pentoxid e in the presence of air. The surface morphology of the final product was found to be dependent on the temperature of synthesis of the mater ial, as evidenced by SEM analysis of the samples. SVO synthesized at 3 20 and 375-degrees-C displayed irregularly shaped particles, while mat erial prepared at 450-degrees-C was needlelike. SVO synthesized at 540 -degrees-C appeared to be a mixture of large crystalline plates and ir regular particles. All of the samples were analyzed by DSC, chemical a nalysis, X-ray powder diffraction, resistivity measurements, and const ant-resistance discharge of Li/SVO test cells. The experimental capaci ties of the lower temperature materials (320, 375-degrees-C) were simi lar to that found for SVO prepared at 450-degrees-C. A significant dec rease in delivered capacity was noted when the SVO prepared at 540-deg rees-C was used as a cathode material.