Sk on Co., Ltd.

Sk Innovation Co., Ltd.

Jeong Bae Yoon

Ji Hoon Choi

Jik Soo Kim

Sang Bok Kim

Sang Min Park

Sang Hye Shin

Tae Kyoung Lee

Min Gu Kang

Myoung Lae Kim

Yong Hyun Cho

Sang Han Lee

Yu Na Shim

Seung Ok Lee

Hee Jun Kweon

A cathode active material for a lithium secondary battery is provided. The cathode active material includes lithium-transition metal composite oxide particles having a crystallite size of 120 nm or less in a () plane direction measured through X-ray diffraction (XRD) analysis, and a ratio of the crystallite size of the lithium-transition metal composite oxide particle in the () plane direction to a crystallite size thereof in a () plane direction isor more.

Cathode active material for lithium secondary battery and method of manufacturing the same

The cathode active material for a lithium secondary battery according to embodiments of the present invention includes a lithium-transition metal composite oxide particle including a plurality of primary particles, and the lithium-transition metal composite oxide particle includes a lithium-sulfur-containing portion formed between the primary particles. Thereby, it is possible to improve life-span properties and capacity properties by preventing the layer structure deformation of the primary particles and removing residual lithium.

Cathode active material for lithium secondary battery and lithium secondary battery including the same

A cathode active material for a lithium secondary battery has a structure of a lithium-nickel-based metal oxide. A crystal size in a (104) plane defined by Equation 1 is less than 200 nm. A thickness of a TM slab measured by a Rietveld method in a crystal structure of a space group R-3m by an X-ray diffraction (XRD) analysis is 2.15 Å or less. A thickness of a Li slab thickness measured by the Rietveld method in the crystal structure of the space group R-3m by the XRD analysis is 2.585 Å or more.

The cathode active material for a lithium secondary battery according to embodiments of the present invention includes lithium-transition metal composite oxide particles including a plurality of primary particles, and the lithium-transition metal composite oxide particles have a lithium-potassium-containing portion formed between the primary particles. Thereby, it is possible to improve life-span properties and capacity properties by preventing the layer structure deformation of the primary particles and removing residual lithium.

A cathode active material for a lithium secondary battery including a lithium-transition metal composite oxide particle is provided. A crystal grain size of the lithium-transition metal composite oxide particle measured by an XRD analysis is 250 nm or more, and an XRD peak intensity ratio of the lithium-transition metal composite oxide particle is 9.8% or less. A lithium secondary battery including the lithium-transition metal composite oxide particle and having improved life-span and rate capability is provided.

A cathode active material for a lithium secondary battery includes a lithium-transition metal composite oxide particle having a lattice strain (η) of 0.18 or less, which is calculated by applying Williamson-Hall method defined by Equation 1 to XRD peaks measured through XRD analysis, and having an XRD peak intensity ratio of 8.9% or less, which is defined by Equation 2. By controlling the lattice strain and XRD peak intensity ratio of the lithium-transition metal composite oxide particle, a lithium secondary battery with improved life-span characteristics as well as output characteristics is provided.

A method of manufacturing a cathode active material for a lithium secondary battery according to embodiments of the present invention includes performing a first heat treatment on a first mixture of a transition metal precursor and a lithium precursor at a first calcination temperature to obtain a preliminary lithium-transition metal composite oxide particle; and performing a second heat treatment on a second mixture obtained by adding the lithium precursor to the preliminary lithium-transition metal composite oxide particle at a second calcination temperature which is lower than the first calcination temperature to form a lithium-transition metal composite oxide particle.

A cathode active material for a lithium secondary battery includes a lithium-transition metal composite oxide particle having a lattice strain (&#x3b7;) of 0.18 or less, which is calculated by applying Williamson-Hall method defined by Equation 1 to XRD peaks measured through XRD analysis, and having an XRD peak intensity ratio of 8.9% or less, which is defined by Equation 2. By controlling the lattice strain and XRD peak intensity ratio of the lithium-transition metal composite oxide particle, a lithium secondary battery with improved life-span characteristics as well as output characteristics is provided.

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Daejeon, South Korea

Jeong Bae Yoon