SYNTHESIS AND CHARACTERIZATION OF A NEW TRIMETALLIC CATHODE MATERIAL FOR LITHIUM BATTERIES

A new cathode material (CuxAgyV2Oz) was investigated as a candidate fo r lithium batteries. Silver and copper-containing starting materials w ere examined in this study, using silver oxide, copper oxide, silver m etal and copper metal, in addition to silver and copper nitrate. The A g:Cu:V metal ion ratios were systematically varied to study. the effec t of this parameter on the electrochemical properties of the material. For CuxAgyV2Oz the metal ion ratios were in the range: 0.1 less than or equal to x less than or equal to 0.6 and 0.2 less than or equal to y less than or equal to 0.8, with 5.2 less than or equal to z less tha n or equal to 5.9 for oxygen. The samples were characterized by differ ential scanning calorimetry, scanning electron microscopy, X-ray powde r diffraction, and constant resistance discharge of test cells, The ex perimental capacity of Cu0.5Ag0.5V2O5.75, (initial open-circuit voltag e = +3.8 V versus Li/Li+) discharged to +1.5 V versus Li/Li+ was 332 m Ah/g, resulting in the formation of Li3.4Cu0.5Ag0.5V2O5.75. (C) 1997 E lsevier Science S.A.