LITHIUM COBALTATE SYSTEM POSITIVE ELECTRODE ACTIVE MATERIAL FOR LITHIUM ION SECONDARY BATTERY, ITS MANUFACTURE, AND LITHIUM ION SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a lithium secondary battery having a high energy density lithium cobaltate system positive material and showing a superior stabilized discharge capacity and cycle characteristic. SOLUTION: In a lithium cobaltate system positive electrode active material for a lithium ion secondary battery, this lithium cabaltate is left standing at a room temperature, so that a measured moisture amount (A) is to be 150 ppm or less by means of the moisture vaporization method at 120 deg.C by the Karl Fischer titration method, and/or this cobalt acid lithium is left standing for twelve hours at 30 deg.C with a relative humidity of 60%, and then measured moisture amount (B) is to be 200 ppm or less by means of the moisture vaporization method at 120 deg.C by the Karl Fischer titration method.