LITHIUM MANGANATE POWDER FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY, METHOD FOR PRODUCING SAME, AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

The present invention provides lithium manganate which has a high output and is excellent in high-temperature stability. The present invention relates to lithium manganate particles which are produced by mixing a lithium compound, a manganese compound, a Y compound and an A compound with each other and then calcining the resulting mixture, and have a composition represented by the following chemical formula 1 and an average secondary particle diameter (D) of 1 to 15 µm, (Chemical Formula) LiMnYO+ zA in which Y is at least one element selected from the group consisting of Al and Mg; A is a sintering aid element having a melting point of not higher than 850°C; x and y satisfy 0.03 ≤ x s 0.15 and 0 ≤ y ≤ 0.20, respectively; z is in the range of 0 to 2.5 mol% based on Mn, wherein the lithium manganate particles have a sulfur content of not more than 100 ppm.