Lg Chem, Ltd

Won Sig Jung

Sang Soon Choi

Hyun Ah Park

Seung Beom Cho

Hwan Young Choi

Tae Young Rhee

Jung Ho Lim

Kang Hyeon Lee

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.

Positive electrode active material, and positive electrode and lithium secondary battery including same

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-sintered mixture; a step for extracting the pre-sintered mixture from the first crucible and pulverizing or classifying the same; and a step for adding the pulverized or classified pre-sintered 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-sintered mixture formed after the first heat treatment is reduced to a volume that is 20-50% of a volume of the reaction mixture added into the first crucible.

Method for preparing positive electrode active material

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.

Method for separating transition metal from waste positive electrode material

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.

Method of washing positive electrode active material, and positive electrode active material prepared thereby

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.

Positive electrode having lithium transition metal oxide containing nickel, cobalt and manganese for secondary battery and secondary battery including the same

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&#xb0; C. to 800&#xb0; 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&#xb0; C. to 1,000&#xb0; 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.

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.

Method for preparing positive electrode active material precursor for lithium secondary battery

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.

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Daejeon, South Korea

Won Sig Jung