Samsung Sdi Co., Inc.

Sang-Woo Cho

Chang-Wook Kim

Ji-Hyun Kim

Yong-Chan You

Sang-In Park

A positive active material for a rechargeable lithium battery includes a core including an overlithiated oxide represented by Chemical Formula 1, a first coating layer on the core and including a compound having a spinel structure, and a second coating layer on the first coating layer and including a compound represented by Chemical Formula 2. The compound having a spinel structure shows a peak between about 2.6 V and about 2.7 V in a graph of differential capacity dQ/dV vs. voltage, where the voltage is between about 4.7 V and about 2.5 V. In Chemical Formula 1, 0&#x3c;x&#x3c;1, 0&#x3c;a&#x3c;1, 0&#x3c;b&#x3c;1, 0&#x3c;c&#x3c;1, and a+b+c=1. In Chemical Formula 2, 0&#x2266;d&#x3c;1 and 0&#x3c;e&#x2266;1.xLiMnO.(1&#x2212;x)LiNiCoMnO,&#x2003;&#x2003;Chemical Formula 1LiTiO.&#x2003;&#x2003;Chemical Formula 2

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

Provided are a positive active material that has a decreased amount of Li-containing impurities that remain on a lithium transition metal composite oxide surface to decrease an amount of gas generation and has improved lifespan properties, a method of preparing the same, a positive electrode for a lithium secondary battery including the positive active material, and a lithium secondary battery including the same.

Positive active material, preparing method thereof, positive electrode for lithium secondary battery including the same, and lithium secondary battery employing the same

Provided are a method of preparing a cathode active material, a composite cathode active material, and a cathode and a lithium battery containing the composite cathode active material. The method includes mixing a transition metal source and a reducing agent to prepare a cathode active material precursor; and mixing and calcining the cathode active material precursor to prepare a lithium transition metal oxide, wherein a supplied amount of the reducing agent is about 0.003 mole/hr or less with respect to 1 mole/hr of a supplied amount of the transition metal source.

Method of preparing composite cathode active material, composite cathode active material, and cathode and lithium battery containing the composite cathode active material

Growing community of inventors

Yongin-si, South Korea

Sang-Woo Cho