Uniform hexagonal-shaped cobalt oxide (Co3O4) nanodisks were prepared in large scale via facile aqueous solution based hydrothermal process at 110 degrees C. The detailed structural characterizations confirmed that the synthesized products are hexagonal cobalt oxide nanodisks, possessing very well-crystalline cubic spinel structure. A coin cell of type -2032 was assembled using the synthesized Co3O4 nanodisks and its charge-discharge profile was analyzed between the voltages 0.01 and to 2.5 V vs. Li/Li+ reference electrode. The electrochemical cell composed of Li/Co3O4 delivered an initial lithium insertion capacity of 2039 mAh/g. Although the cell exhibited high irreversible capacity during the first four cycles, the columbic efficiency has been improved upon cycling. (C) 2011 Elsevier Ltd. All rights reserved.