CATHODE ACTIVE MATERIAL FOR SECONDARY BATTERY

摘要

PURPOSE: A positive active material for a secondary battery is provided to improve the lifetime of a secondary battery and to enable the use for a device required for long term use due to excellent cycle characteristics. CONSTITUTION: A positive active material for a secondary battery comprises lithium in a transition metal layer as a compound of one or two selected from chemical formula 1: Li(Li3x±yM1-yPx)O2+z. In chemical formula, M is one or more elements selected from a first period and a second period as an element stable to a 6 coordinate structure; 0y is satisfied.