| 摘要 |
PROBLEM TO BE SOLVED: To provide a positive electrode active material having a low deterioration level by the charge/discharge cycle and easy to be composited by specifying the initial discharge capacity of a lithium-manganese compound oxide with a layered structure and the discharge capacity reduction factor at a 30-th cycle. SOLUTION: This positive electrode active material of a battery is a lithium- manganese composite oxide with a layered structure expressed by formula I, where L indicates one or two or more kinds of elements selected from among metal elements and non-metal and single-metal elements of IIIB, IVB, VB, VIB groups in the periodic table, and (x), (y) and (z) indicate the ranges expressed in equations II, III, IV, V. The initial discharge capacity is set to 100 mAh/g or above, and the discharge capacity reduction factor at a 30-th cycle in charges/discharges at 3.5-4.5 V is set to 13% or below. A material with a homogeneous composition is easy to be composited, there is no using limit for the raw material, a substitution product is easy to composite, and superior performance with a low deterioration level by charge/discharge cycles is obtained. |
