CATHODE ACTIVE MATERIAL FOR LITHIUM SECONDARY BATTERY, AND LITHIUM SECONDARY BATTERY COMPRISING SAME

• Main Authors: KIM, Tae Gyeong, CHOI, Su An, LIM, Sun Hye, LIM, Young Geun, AN, Ji Sun, JEON, Sang Hoon
• Format: Patent
• Language: English; French; Korean
• Published: 16.05.2019
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

The present invention relates to a cathode active material for a lithium secondary battery, and a lithium secondary battery comprising same. A cathode active material for a lithium secondary battery, according to one embodiment of the present invention, is a secondary particle in which lithium metal oxide primary particles are aggregated, and is represented by chemical formula 1 below, wherein the lithium metal oxide particles have a nickel-based layered structure, the average density of the secondary particle is 0.8 or greater to 1 or less, the Dmin particle size change after pressing at a pressure of 200 MPa is no more than 2.9 μm, and the average particle size of the primary particles may be 0.1 to 1 μm. [Chemical formula 1] Liα[ (ΝixCoy)1-βΑβ]O2. In chemical formula 1, 0.95≤α≤1.05, 0.015≤β≤0.040, 0.73≤x≤0.78, 0.22≤y≤0.27, and A is at least one selected from Al, Ti and Mg. La présente invention concerne un matériau actif de cathode pour batterie secondaire au lithium et une batterie secondaire au lithium comprenant celui-ci. Un matériau actif de cathode pour batterie secondaire au lithium, selon un mode de réalisation de la présente invention, est une particule secondaire dans laquelle sont agrégées des particules primaires d'oxyde métallique de lithium, et est représenté par la formule 1 ci-dessous, les particules d'oxyde métallique de lithium ayant une structure stratifiée à base de nickel, la densité moyenne de la particule secondaire étant supérieure ou égale à 0,8 et inférieure ou égale à 1, la variation de la taille de particules Dmin après compression à une pression de 200 MPa étant inférieure ou égale à 2,9 µm, et la taille particulaire moyenne des particules primaires pouvant être de 0,1 à 1 µm. [Formule 1] Liα[(ΝixCoy)1-βΑβ]O2 리튬 이차 전지용 양극 활물질, 및 이를 포함하는 리튬 이차 전지에 관한 것이다. 일 실시예에 따른 리튬 이차 전지용 양극 활물질은, 리튬 금속 산화물 1차 입자가 집합된 2차 입자이며, 하기 화학식 1로 표시되고, 상기 리튬 금속 산화물 입자는 니켈계 레이어드 구조이며, 상기 2차 입자의 평균 치밀도는 0.8 이상 및 1이하이고, 200 MPa 압력으로 프레스 후 Dmin 입경 변화가 2.9μm이내이고, 상기 1차 입자의 평균 입경은 0.1 내지 1μm일 수 있다. [화학식 1] Liα[ (ΝixCoy)1-βΑβ]O2 상기 화학식 1에서, 0.95 ≤ α ≤ 1.05, 0.015 ≤ β ≤ 0.040, 0.73 ≤ x ≤ 0.78, 및 0.22 ≤ y ≤ 0.27이고, A는 Al, Ti, 및 Mg 중 선택된 적어도 어느 하나이다.