A method of forming an active material for a positive electrode of a lithium-ion battery includes quenching a powder of the active material in water. The active material may include layered lithium rich nickel manganese oxide.

A positive electrode material includes a first lithium manganese iron phosphate material in an aggregate form, a second and third lithium manganese iron phosphate materials in an aggregate and/or single-crystal-like form, and a fourth and fifth lithium manganese iron phosphate materials in a single-crystal-like form. A particle quantity ratio of the first to fifth lithium manganese iron phosphate materials is (0.8 to 1.2):(0.8 to 1.2):(1.6 to 2.4):(6.4 to 9.6):(6.4 to 9.6), and particle size D.sub.50 relationships satisfy: D.sub.50.sup.5<D.sub.50.sup.4<D.sub.50.sup.3<D.sub.50.sup.2<D.sub.50.sup.1, D.sub.50.sup.2=aD.sub.50.sup.1, D.sub.50.sup.3=bD.sub.50.sup.1, D.sub.50.sup.4=cD.sub.50.sup.1, D.sub.50.sup.5=dD.sub.50.sup.1, and 5 μm≤D.sub.50.sup.1≤15 μm, where 0.35≤a≤0.5, 0.2≤b≤0.27, 0.17≤c≤0.18, and 0.15≤d≤0.16.

Provided is a method of producing fine particulate barium calcium titanate in which calcium forms a homogeneous solid solution. The present invention relates to a method of producing a perovskite compound represented by the following formula (1):

Ba.sub.(1-x)A.sub.xTiO.sub.3  (1)

wherein A represents Ca or Sr, and x is a number satisfying 0.00<x≤0.30,

the method including: a first step of acid washing barium titanate to provide barium titanate having a ratio of barium element to titanium element of lower than 1.00; a second step of mixing the barium titanate obtained in the first step and a calcium salt or a strontium salt and drying the mixture to provide a dry mixture; and a third step of heating the dry mixture obtained in the second step.

Provided are a nickel-based active material for a lithium secondary battery, a method of preparing the nickel-based active material, and a lithium secondary battery including a positive electrode including the nickel-based active material. The nickel-based active material includes at least one secondary particle that includes at least two primary particle structures, the primary particle structures each including a porous inner portion and an outer portion having a radially arranged structure, and the secondary particle including at least two radial centers.

A process for gas-phase synthesis of titanium dioxide aerosol gels with controlled monomer size and crystalline phase using a diffusion flame aerosol reactor operated in a buoyancy-opposed configuration is disclosed. The process includes introducing a precursor stream into a diffusion flame aerosol reactor, introducing a fuel stream into the reactor, combusting the precursor stream and the fuel stream in a flame to form at least one nanoparticle, and operating the reactor in a down-fired buoyancy-opposed configuration to produce the aerosol gel.

Core particles produced in situ or introduced as preformed core particles are coated with a layer of carbon. Non-carbon as well as some carbon-based core materials can be utilized. The resulting carbon coated particles can find applications in rubber products, for instance as reinforcement for tire components.

The present disclosure discloses a W-containing high-nickel ternary cathode material, including both spherical secondary particles and single-crystal particles. There is basically no W inside the single-crystal particles, and the spherical secondary particles are doped with W. A preparation method of the W-containing high-nickel ternary cathode material includes: mixing a nickel salt, a cobalt salt, and a manganese salt according to a specified molar ratio, and adding an ammonia solution and a sodium hydroxide solution for co-precipitation to prepare a precursor A; mixing a nickel salt, a cobalt salt, a manganese salt, and a tungsten salt, and adding an ammonia solution and a sodium hydroxide solution for co-precipitation to prepare a W-containing precursor B; and mixing the precursor A, the precursor B, a lithium source, and a doping element M-containing compound, and subjecting a resulting mixture to high-temperature sintering in an oxygen atmosphere to obtain the high-nickel ternary cathode material including both spherical secondary particles and single-crystal particles. While increasing the capacity, the spherical secondary particles in the product of the present disclosure can ensure that a crystal structure will not undergo obvious phase transition when lithium ions are deintercalated during a cycling process, which helps to improve the cycling performance.

The present invention relates to a positive electrode active material comprising an overlithiated layered oxide (OLO) and, more specifically, to a positive electrode active material comprising: an OLO represented by chemical formula 1 below; and an amorphous free oxide coating layer of an amorphous free oxide on the surface of the OLO represented by chemical formula 1. [Chemical formula 1] Li.sub.2MnO.sub.3.(1-r)Li.sub.aNi.sub.xCo.sub.yMn.sub.zM1.sub.1-(x+y+z)O.sub.2 (wherein, in chemical formula 1, 0<r≤0.6, 0<a≤1, 0≤x≤1, 0≤y<1, 0≤z<1, and 0<x+y+z≤1, and M1 is at least any one selected from Na, K, Mg, Al, Fe, Cr, Y, Sn, Ti, B, P, Zr, Ru, Nb, W, Ba, Sr, La, Ga, Mg, Gd, Sm, Ca, Ce, Fe, Al, Ta, Mo, Sc, V, Zn, Cu, In, S, B, Ge, Si, and Bi).

A method of producing a positive electrode material for a secondary battery includes preparing a lithium composite transition metal oxide containing nickel, cobalt, and manganese, forming a coating layer on a surface of the lithium composite transition metal oxide, and post-treating the lithium composite transition metal oxide having the coating layer formed thereon, wherein the post-treating is performed by exposing the lithium composite transition metal oxide having the coating layer formed thereon to moisture at a relative humidity of 10% to 50% at 25° C., and then heat treating the lithium composite transition metal oxide to remove residual moisture.

A positive electrode active material includes a lithium transition metal oxide, which is in the form of a secondary particle formed by aggregation of primary particles and is represented by Formula 1, wherein the lithium transition metal oxide has a crystalline size of 160 nm or less and an average particle diameter of the primary particle of 0.6 μm or more. A preparation method thereof is also provided.