Abstract: Provided is a positive electrode active material which includes an inner region that is a region from the center of the positive electrode active material particle to R/2, and an outer region that is a region from R/2 to the surface of the positive electrode active material particle, wherein R is a distance from the center of the positive electrode active material particle to the surface thereof. The positive electrode active material further includes 25% to 80% of crystallites C with respect to a total number of crystallites in the outer region. The crystallites C have a high crystallite long-axis orientation degree of 0.5 to 1 and a low crystallite c-axis orientation degree less than 0.5. Thus, the positive electrode active material has high capacity characteristics and a small amount of gas generated.

Abstract: Provided is a positive electrode active material including a plurality of crystallites A, wherein the plurality of crystallites A has a crystallite long-axis orientation degree DoA represented by Equation 1 below is 0.5 to 1, and a crystallite c-axis orientation degree represented by a cross product value of a c-axis rotation vector Rc of a crystal lattice of a crystallite obtained by electron backscatter diffraction (EBSD) analysis and a position unit vector P? of the crystallite is 0.5 to 1. A proportion of the plurality of crystallites A is 25% to 80% with respect to a total number of crystallites in a cross-section of a positive electrode active material. Further provided is a positive electrode and a lithium secondary battery including the positive electrode active material.

Abstract: Provided is a positive electrode active material which includes an inner region that is a region from the center of the positive electrode active material particle to R/2; and an outer region that is a region from R/2 to the surface of the positive electrode active material particle, wherein R is a distance from the center of the positive electrode active material particle to the surface thereof. The positive electrode active material further includes 30% to 80% of crystallites A with respect to a total number of crystallites in the outer region of the positive electrode active material, the crystallites A having high crystallite long-axis orientation degree and crystallite c-axis orientation degree. Thus, the positive electrode active material can achieve excellent capacity characteristics and service life characteristics.

Abstract: A positive electrode for a secondary battery includes a positive electrode active material layer, which includes a positive electrode active material including a lithium transition metal oxide which contains nickel, cobalt, and manganese and has an atomic ratio of nickel in total transition metals of 80 atm % or more, and a metal oxide including a metallic element having a binding potential with lithium of 0.5 V to 4 V. A secondary battery including the positive electrode is also provided.

Abstract: A positive electrode active material, a method of preparing the same, a positive electrode and a lithium secondary battery including the same are disclosed herein. In some embodiments, a positive electrode active material including a lithium transition metal oxide which contains 60 mol % or more of nickel based on a total number of moles of transition metals excluding lithium in the lithium transition metal oxide, is in a form of a secondary particle which is an aggregate of primary particles, wherein the lithium transition metal oxide satisfies Equation 1: 2 ? 0 < x y wherein x is a minimum area of a rectangle including all pores having an area greater than 0.002 ?m2 among closed pores distributed in the secondary particle, and y is a total sum of areas of the pores having an area greater than 0.002 ?m2 among the closed pores distributed in the secondary particle.

Abstract: A positive electrode active material has crystalline C having a crystalline major-axis orientation degree DoA of 0.5 to 1 and a crystalline c-axis orientation degree of less than 0.5, wherein among total crystallines in a cross section of a positive electrode active material particle, a ratio of the crystalline C is in a range of 25% to 70%. A positive electrode and a lithium secondary battery which include the same are also provided.

Abstract: A method of preparing a positive electrode active material which includes a first step of preparing a cake including a lithium transition metal oxide having a lithium borate compound formed on a surface thereof by mixing a positive electrode active material precursor having a specific composition, a lithium-containing raw material, and a boron-containing raw material and sintering the mixture, and a second step of grinding the cake and washing the ground cake to prepare a lithium transition metal oxide having the lithium borate compound removed therefrom. The method reduces the problems of breaking lithium transition metal oxide during the post processing steps by reduction in cake strength and change in the strength over time, thereby providing a positive electrode active material having improved quality.

Abstract: A positive electrode active material, a positive electrode including the positive electrode active material, and a lithium secondary battery including the same are disclosed herein. In some embodiments, the positive electrode active material includes a lithium transition metal oxide containing nickel in an amount of 60 mol% or greater based on a total number of moles of transition metals in the lithium transition metal oxide, and in the form of a secondary particle which is an aggregate of primary particles. The positive active material satisfies Equation (1) : -0.021x + 4.0 ? y ? -0.021x + 5.5, wherein x is a crystal grain size (nm) of the positive electrode active material, and y is a crystal grain aspect ratio of the positive electrode active material.

Abstract: A method for separating a transition metal from a waste positive electrode material includes step 1 of preparing a waste positive electrode material represented by Formula 1, step 2 of heat treating the waste positive electrode material in an inert gas atmosphere or an oxygen atmosphere to phase separate the waste positive electrode material into a lithium oxide and a metal oxide, step 3 of cooling an obtained product of step 2 to room temperature in an inert atmosphere, and step 4 of mixing a cooled product cooled to room temperature in step 3 with distilled water, and then filtering the mixture to leach a transition metal.

Abstract: A method for producing a positive electrode active material includes washing a lithium transition metal oxide with a washing solution, and solid-phase mixing the washed lithium transition metal oxide and a metal phosphate compound having a melting point of 500° C. or lower, followed by performing heat treatment to form a coating layer on the surface of the lithium transition metal oxide.

Abstract: A method of preparing a positive electrode active material which includes forming a pre-sintered mixture by adding a reaction mixture including a lithium raw material and a nickel-manganese-cobalt precursor to a first crucible and performing a primary heat treatment at a temperature of 500° C. to 800° C., and, after discharging the pre-sintered mixture from the first crucible, adding the pre-sintered mixture to a second crucible and performing a secondary heat treatment at a temperature of 700° C. to 1,000° C. to form a lithium nickel manganese cobalt-based positive electrode active material, wherein a volume of the pre-sintered mixture formed after the primary heat treatment is 20% to 50% of a volume of the reaction mixture added to the first crucible.

Abstract: The present invention provides a method of preparing a positive electrode active material precursor for a lithium secondary battery, a method of preparing a positive electrode active material for a lithium secondary battery in which the positive electrode active material precursor prepared by using the above method is used, and a positive electrode for a lithium secondary battery and a lithium secondary battery which include the positive electrode active material.

Abstract: A method of washing a positive electrode active material includes (1) preparing a lithium composite transition metal oxide which contains Ni, Co and Mn, and has the Ni content of 60 mol % or more; (2) putting the lithium composite transition metal oxide into water; and (3) adding a weak acid to water to which the lithium composite transition metal oxide is added to adjust the pH to 7 to 10, wherein the acid is a weak acid.

Abstract: A positive electrode for a secondary battery includes a positive electrode active material layer, which includes a positive electrode active material including a lithium transition metal oxide which contains nickel, cobalt, and manganese and has an atomic ratio of nickel in total transition metals of 80 atm % or more, and a metal oxide including a metallic element having a binding potential with lithium of 0.5 V to 4 V. A secondary battery including the positive electrode is also provided.

Abstract: A method of preparing a positive electrode active material which includes forming a pre-sintered mixture by adding a reaction mixture including a lithium raw material and a nickel-manganese-cobalt precursor to a first crucible and performing a primary heat treatment at a temperature of 500° C. to 800° C., and, after discharging the pre-sintered mixture from the first crucible, adding the pre-sintered mixture to a second crucible and performing a secondary heat treatment at a temperature of 700° C. to 1,000° C. to form a lithium nickel manganese cobalt-based positive electrode active material, wherein a volume of the pre-sintered mixture formed after the primary heat treatment is 20% to 50% of a volume of the reaction mixture added to the first crucible.

Abstract: A method of preparing a positive electrode active material that includes introducing a reaction mixture including a lithium source material and a nickel-manganese-cobalt precursor into a continuous firing furnace and subjecting the same to primary heat treatment, thereby preparing a fired mixture; subjecting the fired mixture to pulverization or size classification; and introducing the fired mixture having been pulverized or size-classified into a rotary kiln and subjecting the same to secondary heat treatment, thereby forming a lithium nickel manganese cobalt-based positive electrode active material.

Abstract: A method of preparing a positive electrode active material precursor for a lithium secondary battery by using a batch-type reactor, which includes the steps of 1) forming positive electrode active material precursor particles while continuously adding a transition metal-containing solution including a transition metal cation, an aqueous alkaline solution, and an ammonium ion-containing solution to a batch-type reactor, 2) sedimenting the positive electrode active material precursor particles formed; 3) discharging a supernatant formed after the sedimentation of the positive electrode active material precursor particles to an outside; 4) adjusting a pH to 10 to 12 by adding the ammonium ion-containing solution; and 5) growing the positive electrode active material precursor particles while continuously again adding the transition metal-containing solution to the batch-type reactor, and a method of preparing a positive electrode active material using the same.

Abstract: A method for preparing a positive electrode active material includes: a step for adding a reaction mixture containing a lithium-raw material and a nickel-manganese-cobalt precursor into a first crucible and performing a first heat treatment at a temperature of 500-800° C. to form a pre-calcinated mixture; a step for extracting the pre-calcinated mixture from the first crucible and pulverizing or classifying the same; and a step for adding the pulverized or classified pre-calcinated mixture into a second crucible and performing a second heat treatment at a temperature of 700-1000° C. under an atmosphere in which an oxygen partial pressure is 20% or less to form a lithium nickel-manganese-cobalt-based positive electrode active material, wherein a volume of the pre-calcinated mixture formed after the first heat treatment is 20-50% with respect to a volume of the reaction mixture added into the first crucible.

Abstract: The present invention provides a method of preparing a positive electrode active material precursor for a lithium secondary battery, a method of preparing a positive electrode active material for a lithium secondary battery in which the positive electrode active material precursor prepared by using the above method is used, and a positive electrode for a lithium secondary battery and a lithium secondary battery which include the positive electrode active material.

Abstract: A method of preparing a positive electrode active material precursor for a lithium secondary battery by using a batch-type reactor, which includes the steps of 1) forming positive electrode active material precursor particles while continuously adding a transition metal-containing solution including a transition metal cation, an aqueous alkaline solution, and an ammonium ion-containing solution to a batch-type reactor, 2) sedimenting the positive electrode active material precursor particles formed; 3) discharging a supernatant formed after the sedimentation of the positive electrode active material precursor particles to an outside; 4) adjusting a pH to 10 to 12 by adding the ammonium ion-containing solution; and 5) growing the positive electrode active material precursor particles while continuously again adding the transition metal-containing solution to the batch-type reactor, and a method of preparing a positive electrode active material using the same.