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

• Main Authors: Hong, Mingzi, Kim, Young-Ki, Hong, Soonkie, Chae, Youngjoo, Lee, Soonrewl, Choi, Ickkyu, Park, Jungjoon
• Format: Patent
• Language: English
• Published: 29.11.2022
• Subjects: BASIC ELECTRIC ELEMENTS; CABLES; CONDUCTORS; ELECTRICITY; INSULATORS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING ORDIELECTRIC PROPERTIES

A positive active material for a rechargeable lithium battery includes a first compound represented by Chemical Formula 1, and a second compound represented by Chemical Formula 2 and having a smaller particle diameter than the first compound, wherein at least one of the first compound and the second compound includes a core and a surface layer surrounding the core:Lia1Nix1Coy1M11-x1-y1O2,  Chemical Formula 1Lia2Nix2Coy2M21-x2-y2O2,  Chemical Formula 2wherein M1 and M2 are each independently at least one selected from Mn, Al, Cr, Fe, V, Mg, Ti, Zr, Nb, Mo, W, Cu, Zn, Ga, In, Sn, La, and Ce. The atomic concentration (at %) of nickel (Ni) with respect to the total amount of non-lithium metals is higher in the surface layer than in the core, and an amount of cation mixing is less than or equal to about 3%.