A method of producing a positive electrode active material for a nonaqueous electrolyte secondary battery, the method includes preparing nickel-containing composite oxide particles having a ratio .sup.1D.sub.90/.sup.1D.sub.10 of a 90% particle size .sup.1D.sub.90 to a 10% particle size .sup.1D.sub.10 in volume-based cumulative particle size distribution of 3 or less; obtaining a raw material mixture containing the composite oxide particles and a lithium compound and having a ratio of a total number of moles of lithium to a total number of moles of metal elements contained in the composite oxide in a range of 1 to 1.3; subjecting the raw material mixture to a heat treatment to obtain a heat-treated material; subjecting the heat-treated material to a dry-dispersion treatment to obtain a first dispersion; and bringing the first dispersion into contact with a liquid medium to obtain a second dispersion.

A method of producing a positive electrode active material for a nonaqueous electrolyte secondary battery, the method includes preparing nickel-containing composite oxide particles having a ratio .sup.1D.sub.90/.sup.1D.sub.10 of a 90% particle size .sup.1D.sub.90 to a 10% particle size .sup.1D.sub.10 in volume-based cumulative particle size distribution is 3 or less; mixing the composite oxide particles and a lithium compound to obtain a first mixture; subjecting the first mixture to a first heat treatment at a first temperature and a second heat treatment at a second temperature higher than the first temperature to obtain a first heat-treated product; and subjecting the first heat-treated material to a dispersion treatment.

A method of preparing a positive electrode active material precursor for a secondary battery includes continuously adding a nickel (Ni), cobalt (Co), and manganese (Mn) transition metal cation-containing solution, an alkaline solution, and an ammonium ion-containing solution to a reactor, and forming a positive electrode active material precursor, in which nickel (Ni) and cobalt (Co) are in non-oxidized hydroxide forms and manganese (Mn) is in an oxidized form, by co-precipitation while a gas is not added or an oxygen-containing gas is continuously added to the reactor. A positive electrode active material precursor for a secondary battery is also provided which includes nickel (Ni), cobalt (Co), and manganese (Mn), wherein the nickel (Ni) and the cobalt (Co) are in non-oxidized hydroxide forms, and the manganese (Mn) is in an oxidized form.

Provided are an apparatus for preparing a cathode active material precursor for lithium secondary batteries including a cylindrical outer chamber, an inner cylinder that has the same central axis as the outer chamber and is mounted to rotatably move along the central axis, an electric motor to transfer power to rotate the inner cylinder, a reactant inlet disposed on the outer chamber, to add reactants to a space between the outer chamber and the inner cylinder, and an outlet disposed in the outer chamber, to obtain reaction products after reaction in the space between the outer chamber and the inner cylinder, and a method for preparing a cathode active material precursor for lithium secondary batteries using the apparatus.

A lithium deficient cathode active material for lithium-ion batteries is described. More particularly, the lithium deficient cathode active material can have multiphase structures, including both a layered or hexagonal structure (e.g., having an R-3m space group) and a spinel structure (e.g., having a .sub.Fd-m space group). Batteries including the cathode active material and methods of preparing the cathode active material are also described.

Provided are a nickel-based active material precursor for a lithium secondary battery including a porous core and a shell on the porous core, the shell having a radial arrangement structure with a higher density than that of the porous core, wherein the nickel-based active material precursor have a size of 9 μm to 14 μm, and the porous core has a volume of about 5% by volume to about 20% by volume based on the total volume of the nickel-based active material precursor; a method of preparing the nickel-based active material precursor; a nickel-based active material produced from the nickel-based active material; and a lithium secondary battery including a cathode containing the nickel-based active material.

A method of making highly an active mixed transition metal oxide material has been developed. The method may include sulfiding the metal oxide material to generate metal sulfides which are used as catalyst in a conversion process such as hydroprocessing. The hydroprocessing may include hydrodenitrification, hydrodesulfurization, hydrodemetallation, hydrodesilication, hydrodearomatization, hydroisomerization, hydrotreating, hydrofining, and hydrocracking.

Cathode material from exhausted lithium ion batteries are dissolved in a solution for extracting the useful elements Co (cobalt), Ni (nickel), Al (Aluminum) and Mn (manganese) to produce active cathode materials for new batteries. The solution includes compounds of desirable materials such as cobalt, nickel, aluminum and manganese dissolved as compounds from the exhausted cathode material of spent cells. Depending on a desired proportion, or ratio, of the desired materials, raw materials are added to the solution to achieve the desired ratio of the commingled compounds for the recycled cathode material for new cells. The desired materials precipitate out of solution without extensive heating or separation of the desired materials into individual compounds or elements. The resulting active cathode material has the predetermined ratio for use in new cells, and avoids high heat typically required to separate the useful elements because the desired materials remain commingled in solution.

A cathode active material for a lithium secondary battery according to an embodiment of the present invention includes a lithium-transition metal composite oxide particle having a single particle shape, and a first coating layer formed on a surface of the lithium-transition metal composite oxide particle. The first coating layer includes a Sr—Zr—O compound. Life-span and capacity properties are improved by a combination of the lithium-transition metal composite oxide particle having the single particle shape and the first coating layer formed thereon.

The method includes: a dry mixing process of mixing a tungsten compound with a lithium nickel manganese cobalt-containing composite oxide that is a base material to obtain a mixture; a water spray mixing process of spraying water to the mixture while the mixture is stirred, to mix the mixture; a heat treatment process of subjecting the mixture obtained after the water spray mixing process to a heat treatment at a temperature of 500° C. or lower; and a drying process of drying the mixture obtained after the heat treatment process at a temperature of 500° C. or lower to obtain a W- and Li-containing compound-coated lithium nickel manganese cobalt-containing composite oxide in which fine particles and coating films of a W- and Li-containing compound exist on a surface of the primary particles, and in at least drying process, the drying is performed using a vacuum dry mixing apparatus in a vacuum atmosphere.