| 摘要 |
A positive electrode active material is provided to ensure high capacity, excellent cycle characteristics, and improved storage and high-temperature stabilities, and to be manufactured in a low production cost and with a high production efficiency. A positive electrode active material includes a lithium mixed transition metal oxide having a composition represented by the formula 1 of LixMyO2, wherein a Li2CO3 content determined by pH titration is 0.07% or less. The lithium mixed transition metal oxide is prepared by a solid phase reaction of a mixed transition metal precursor and Li2CO3 under an oxygen-deficient atmosphere. In the formula 1, M = M'_(1-k)A_k, wherein M' is Ni_(1-a-b)(Ni_1/2Mn_1/2)_aCo_b(wherein, 0.65<=a+b<=0.85 and 0<=b<=0.6), A is a dopant, 0<=k<0.05, and x+y≒2(wherein, 0.95<=x<=1.05). |
