There is provided a method for collecting and reusing an active material from positive electrode scrap. The method of reusing a positive electrode active material of the present disclosure includes (a-1) immersing a positive electrode scrap comprising an active material layer on a current collector into a basic solution to separate the active material layer from the current collector, (a-2) thermally treating the active material layer in air for thermal decomposition of a binder and a conductive material in the active material layer, and collecting an active material in the active material layer, (b) washing the active material collected from the step (a-2) with a lithium compound solution which is basic in an aqueous solution and drying, and (c) annealing the active material washed from the step (b) with a lithium precursor to obtain a reusable active material.

The present exemplary embodiments relate to a positive electrode active material and a lithium secondary battery including the same. The positive active material for a lithium secondary battery according to an exemplary embodiment includes lithium metal oxide particles including lithium, nickel, cobalt, manganese and doping elements, and includes a first domain and a second domain inside the lithium metal oxide particles.

The present invention provides that powder is mainly constituted from secondary particles of hydroxyapatite. The secondary particles are obtained by drying a slurry containing primary particles of hydroxyapatite and aggregates thereof and granulating the primary particles and the aggregates. A bulk density of the powder is 0.65 g/mL or more and a specific surface area of the secondary particles is 70 m.sup.2/g or more. The powder of the present invention has high strength and is capable of exhibiting superior adsorption capability when it is used for an adsorbent an adsorption apparatus has.

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.

The present exemplary embodiments relate to a cathode active material, a manufacturing method thereof, and a lithium secondary battery including the same. A cathode active material according to an exemplary embodiment is a lithium metal oxide particle in the form of a secondary particle including a primary particle, a coating layer including a boron compound is positioned on at least a portion of a surface of the primary particle, and the boron compound includes an amorphous structure.

An advantage is to provide a non-aqueous electrolyte secondary battery with improved heat resistance. A positive electrode active material contains a lithium-transition metal composite oxide containing 80 mol % or more of Ni and 0.1 mol % to 1.5 mol % of B on the basis of the total number of moles of metal elements excluding Li, and B and at least one element (M1) selected from Groups 4 to 6 are present on at least the surfaces of particles of the composite oxide. When particles having a volume-based particle size larger than 70% particle size (D70) are first particles, and particles having a volume-based particle size smaller than 30% particle size (D30) are second particles, the molar fraction of M1 on the basis of the total number of moles of metallic elements excluding Li on the surfaces of the second particles is greater than that of the first particles.

The present invention belongs to the field of battery materials, and relates to a process for preparing a particulate lithium manganese nickel spinel compound, and materials produced by the process. The process of the invention uses Mn-containing precursors, Ni-containing precursors, Li-containing precursors and optionally M-containing precursor which form substantially no NOx ases during calcination. The particulate lithium manganese nickel spinel compound product of the process may find use in a lithium ion battery.

A positive electrode active material for a secondary battery includes a first positive electrode active material and a second positive electrode active material, wherein an average particle diameter (D.sub.50) of the first positive electrode active material is twice or more than an average particle diameter (D.sub.50) of the second positive electrode active material, and the second positive electrode active material has a crystallite size of 200 nm or more.

Regeneration of degraded cathode particles in lithium-ion batteries is achieved using a combination of hydrothermal treatment of cycled electrode particles followed by short thermal annealing. The methods provide for direct regeneration of Li-ion cathode materials including LiCoO.sub.2, LiMn.sub.2O.sub.4, LiFePO.sub.4, and Li.sub.xNi.sub.y Mn.sub.z Co.sub.1−y−zO.sub.2, in an economical and environmentally-friendly process.

Provided is a medical calcium carbonate composition that highly satisfies 1) tissue affinity, 2) in vivo resorbability, 3) reactivity, and 4) mechanical strength required for medical materials to be implanted in vivo, a medical calcium phosphate composition, a medical carbonate apatite composition, a medical calcium hydroxide porous structure, a medical calcium sulfate setting granules, and a bone defect regeneration kit related to the medical calcium carbonate composition, and methods for producing these. The medical composition calcium carbonate that highly satisfies the above described elements, and related medical compositions can be produced by controlling the polymorph or structure of calcium carbonate.