LITHIUM-MANGANESE COMPOSITE OXIDE, SECONDARY BATTERY, AND ELECTRIC DEVICE

摘要

The amount of lithium ions that can be received and released in and from a positive electrode active material is increased, and high capacity and high energy density of a secondary battery are achieved. Provided is a lithium-manganese composite oxide represented by LixMnyMzOw, where M is a metal element other than Li and Mn, or Si or P, and y, z, and w satisfy 0 ≤ x/(y + z) < 2, y > 0, z > 0, 0.26 ≤ (y + z)/w < 0.5, and 0.2 < z/y < 1.2. The lithium manganese composite oxide has high structural stability and high capacity.