Positive active material for rechargeable lithium battery, method for preparing same and rechargeable lithium battery including same

摘要

A positive active material including a compound represented by Li1+xM1−kMekO2. A surface part of a particle of the positive active material has a mole ratio [Me/M] (A) of element represented by Me to element represented by M in Li1+xM1−kMekO2 of 0.05≦A≦0.60; the entire particle has a mole ratio [Me/M] (B) of element represented by Me to element represented by M in Li1+xM1−kMekO2 of 0.003≦B≦0.012; and element represented by Me has a concentration difference of between two positions of less than or equal to about 0.02 wt % in an inner part of the particle.;In Li1+xM1−kMekO2, −0.2≦x≦0.2, 0

主权项

1. A positive active material for a rechargeable lithium battery, comprising:
a compound represented by the following Chemical Formula 1, wherein a surface part of a particle of the positive active material has a mole ratio [Me/M] (A) of an element represented by Me to an element represented by M in the following Chemical Formula 1 of 0.05≦A≦0.60; wherein the surface part and an inner part are partitioned by an interface at which the surface part and the inner part contact one another; wherein the surface part is designated as the portion of the particle from the surface of the particle to the interface, and the inner part is designated as the portion of the particle inside of the interface; wherein the interface is positioned at a depth of about 3 nm to about 5 nm from the surface of the particle to the center of the particle; wherein the entire particle has a mole ratio [Me/M] (B) of the element represented, by Me to the element represented by M in the following Chemical Formula 1 of 0.003≦B≦0.012; and wherein the element represented by Me has a concentration difference of between two positions of less than or equal to about 0.02 wt % in the inner part of the particle,
Li1+xM1−kMekO2  [Chemical Formula 1] wherein, −0.2≦x≦0.2, 0