Effect of synthesis conditions on electrochemical, electrophysical and structural characteristics of lithium cobalt oxide
The processes of thermodestruction of lithium and cobalt oxides and their mixtures have been studied. The studies using the IR-spectroscopy as well thermogravimetric analysis showed, that during the initial stage of heating the mixtures of lithium and cobalt acetates the double salts form, and only then their thermodestruction proceeds. Using the methods of complexonometric and iodometric titration the change of oxidative – reductive state of cobalt during the thermodestruction process has been studied, it has been found, that the increase in synthesis temperature leads to the decrease in the oxidation degree of cobalt. The phase composition as well electrochemical properties of materials obtained have been studied using the methods of X-ray phase analysis, scanning electron microscope and chronopotentiometry. It was shown, that the formation of complex cobalt oxides starts at enough low temperatures (350°C). But electrochemical capacity of these products is not high due to a low degree of crystallinity. Products obtained at 750°C possess the highest electrochemical capacity.