Preparation Of Lithium-Intercalated Cobalt Vanadates
Sally Smith* and John Chemical (Mentor), Chemistry Department
We are interested in improving the lithium ion batteries used in portable devices by preparing a bimetallic oxide cathode material, which allows more efficient charge transfer than current cathode materials. We have prepared samples of cobalt vanadates through coprecipitation under basic conditions and ultrasound under acidic conditions. Two new compounds were produced: a cobalt hydroxy pyrovanadate and a layered polyoxyvanadate intercalated with cobalt ions. The samples were characterized through elemental analysis, infrared spectroscopy, and powder X-ray diffraction. We have also investigated the thermal decomposition patterns of the samples. We have explored several chemical routes (LiI, nBuLi, LiOH, various pH and thermal programs) for intercalating lithium ions into these materials. The resulting lithium-inclusion compounds were structurally compared with commercial and prepared lithium cobaltate. We are currently working to increase the lithium ion storage capacity of the cobalt vanadates.