Provided are a positive active material for a lithium secondary battery, a method of preparing the positive active material, a positive electrode for a lithium secondary battery including the positive active material, and a lithium secondary battery including a positive electrode including the positive active material, in which the positive active material may include a nickel-based lithium metal oxide secondary particle including a plurality of large primary particles, the nickel-based lithium metal oxide secondary particle may have a hollow structure having a pore inside, a size of each of the large primary particles may be in a range of about 2 micrometers (μm) to about 6 μm, and a size of the nickel-based lithium metal oxide secondary particle may be in a range of about 10 μm to about 18 μm.

A radio wave absorber includes a base member, and a radio wave absorption film formed on the base member. The radio wave absorption film includes at least MTC-substituted ε-Fe.sub.2O.sub.3 and black titanium oxide. The MTC-substituted ε-Fe.sub.2O.sub.3 is a crystal belonging to the same space group as an ε-Fe.sub.2O.sub.3 crystal and expressed by ε-M.sub.xTi.sub.yCo.sub.yFe.sub.2−2y−xO.sub.3 where M is at least one element selected from the group consisting of Ga, In, Al, and Rh, 0<x<1, and 0<y<1.

A paramagnetic garnet-type transparent ceramic is a sintered body of complex oxide represented by the following formula (1), comprising SiO.sub.2 as a sintering aid in an amount of more than 0% by weight to 0.1% by weight or less, and has a linear transmittance of 83.5% or more at the wavelength of 1,064 nm for an optical path length of 25 mm:
(Tb.sub.1-x-yY.sub.xSc.sub.y).sub.3(Al.sub.1-zSc.sub.z).sub.5O.sub.12  (1)
wherein 0.05≤x<0.45, 0<y<0.1, 0.5<1−x−y<0.95, and 0.004<z<0.2.

According to this method, a fatty acid of CnH.sub.2nO.sub.2 (n=5 to 14) is mixed with a plurality of metal sources selected from Zn, In, Sn, Sb, and Al, thereby fatty acid metal salts are obtained, subsequently the fatty acid metal salts are heated at 130° C. to 250° C., and a metal soap that is a precursor is obtained. This precursor is heated at 200° C. to 350° C., and metal oxide primary particles are dispersed in the precursor melt. To this dispersion liquid, a washing solvent having a δP value higher by 5 to 12 than the δP value of the Hansen solubility parameter of the final dispersing solvent is added, thereby the metal oxide primary particles are washed and agglomerated, metal oxide secondary particles are obtained, and then washing is repeated.

A lithium-ion conducting composite material includes a Li binary salt, a Li-ion conductor with a chemical composition of Li.sub.2−3x+y−zFe.sub.xO.sub.y(OH).sub.1−yCl.sub.1−z, and at least two of: a first inorganic compound with a chemical composition of (Fe.sub.1−xM1.sub.x)O.sub.1−y(OH).sub.yCl.sub.1−x; a second inorganic compound with a chemical composition of M2OX; and a defected doped inorganic compound with a chemical composition of (M3OX)′. The value of n is 1 or 2, x is greater than 0 and less than or equal to 0.25, and y is greater than or equal to 0 and less than or equal to 0.25. Also, M1 is at least one of Mg and Ca, M2 and M3 are each at least one of Fe, Al, Sc, La, and Y, and X is at least one of F, Cl, Br, and I.

Provided are a cathode active material having a suitable particle size and high uniformity, and a nickel composite hydroxide as a precursor of the cathode active material. When obtaining nickel composite hydroxide by a crystallization reaction, nucleation is performed by controlling a nucleation aqueous solution that includes a metal compound, which includes nickel, and an ammonium ion donor so that the pH value at a standard solution temperature of 25° C. becomes 12.0 to 14.0, after which, particles are grown by controlling a particle growth aqueous solution that includes the formed nuclei so that the pH value at a standard solution temperature of 25° C. becomes 10.5 to 12.0, and so that the pH value is lower than the pH value during nucleation. The crystallization reaction is performed in a non-oxidizing atmosphere at least in a range after the processing time exceeds at least 40% of the total time of the particle growth process from the start of the particle growth process where the oxygen concentration is 1 volume % or less, and with controlling an agitation power requirement per unit volume into a range of 0.5 kW/m.sup.3 to 4 kW/m.sup.3 at least during the nucleation process.

The present invention relates to a ceramic, to a process for preparing the ceramic and to the use of the ceramic as a dielectric in a capacitor.

The present disclosure relates to a positive electrode active material, a method of manufacturing the same, and a lithium secondary battery including a positive electrode including the same. The positive electrode active material includes: a lithium transition metal oxide particle in which a portion of Li is substituted with Na, and which includes Ni and Co atoms; and a phosphorus-containing coating layer disposed on the surface of the lithium transition metal oxide particle, wherein the lithium transition metal oxide particle includes a concentration gradient region in which the concentration of Co atoms decreases from the surface toward the center of the particle.

This application discloses a positive electrode active material and a preparation method thereof, a positive electrode plate, a lithium-ion secondary battery, and a battery module, battery pack, and apparatus containing such lithium-ion secondary battery. The positive electrode active material includes bulk particles and an element M.sup.1-containing oxide coating layer applied on an exterior surface of each of the bulk particles. The bulk particle includes a nickel-containing lithium composite oxide. Bulk phases of the bulk particles are uniformly doped with element M.sup.2. A surface layer of the bulk particle is an exterior doped layer doped with element M.sup.3. Element M.sup.1 and element M.sup.3 are each independently selected from one or more of Mg, Al, Ca, Ce, Ti, Zr, Zn, Y, and B, and element M.sup.2 includes one or more of Si, Ti, Cr, Mo, V, Ge, Se, Zr, Nb, Ru, Rh, Pd, Sb, Te, Ce, and W.

Provided is a titanium oxide particle dispersion liquid with an inhibited photocatalytic activity and a low level of coloration. Titanium oxide particles in this dispersion liquid contain:

(1) a tin component; and

(2) a manganese component and/or a cobalt component,

wherein only the tin component is solid-dissolved in the titanium oxide particles, and the manganese component and/or the cobalt component are each contained by an amount of 5 to 5,000 in terms of a molar ratio to titanium (Ti/Mn and/or Ti/Co).