A positive electrode active material for a non-aqueous electrolyte secondary battery according to an embodiment of the present disclosure is represented by a general formula of Li.sub.xNi.sub.yM.sub.1-yO.sub.2 (where M includes at least one metal element selected from Co and Mn, 0.1≤x≤1.2, 0.3<y<1), has a volumetric average particle size (D50) of 7 μm or more and 30 μm or less, and has an average surface roughness of 4%, or less.

The present invention provides a composite oxide that can achieve a high low-temperature output characteristic, a method for manufacturing the same, and a positive electrode active material in which the generation of soluble lithium is suppressed and a problem of gelation is not caused during the paste preparation. A positive electrode active material for non-aqueous electrolyte secondary batteries, including a lithium-metal composite oxide powder including a secondary particle configured by aggregating primary particles containing lithium, nickel, manganese, and cobalt, or a lithium-metal composite oxide powder including both the primary particles and the secondary particle. The secondary particle has a porous structure inside as a main inside structure, the slurry pH is 11.5 or less, the soluble lithium content rate is 0.5 [% by mass] or less, the specific surface area is 3.0 to 4.0 [m.sup.2/g], and the porosity is more than 50 to 80 [%].

Provided is a shortened fibrous carbon nanohorn aggregate (CNB) obtained by shortening a CNB having a length of 1 μm or more and a diameter in the short direction in the range of 30 to 100 nm, by oxidizing, stirring in an acid solution, subjecting to an ultrasonic treatment in a liquid, followed by cutting. The shortened CNB has an end surface on which no tip of the plurality of single-walled carbon nanohorns is disposed toward the longitudinal direction at least one end in the longitudinal direction, and has an excellent dispersibility by shortening the length to less than 1 μm.

Disclosed herein are systems and methods from processing flue gas desulfurization (FGD) gypsum feedstock and ash feedstocks, either separately or together. FGD gypsum conversion comprises reacting FGD gypsum (calcium sulfate) feedstock or phosphogypsum, in either batch or continuous mode, with ammonium carbonate reagent to produce commercial products comprising ammonium sulfate and calcium carbonate. A process to separate the impurities and convert the calcium carbonate to a pure precipitated calcium carbonate is disclosed. These impurities include a concentrate of valuable Rare Earth Elements, and radioactive thorium and uranium. A process to convert calcium sulfite to calcium sulfate using oxygen and a catalyst is also disclosed. Ash conversion comprises a leach process followed by a sequential precipitation process to selectively precipitate products at predetermined pHs resulting in metal hydroxides which may be converted to oxides or carbonates. The processes may be controlled by use of one or more processors.

A polishing composition that can not only achieve high polishing speed, but also can improve the surface smoothness (surface quality) of a polished substrate and reduce defects is provided. That is, provided is a polishing composition comprising silica particles and a water soluble polymer, wherein the contained silica particles satisfy the following requirements (a) to (c): (a) the primary particle diameter based on the specific surface area is 5 to 300 nm; (b) the coefficient of variation in the particle diameter is 10% or less; and (c) the Sears number Y is 10.0 to 12.0.

A positive active material for a rechargeable lithium battery includes a lithium nickel-based composite oxide including a secondary particle in which a plurality of plate-shaped primary particles are agglomerated; and a lithium manganese composite oxide having at least two crystal lattice structures, wherein the secondary particle has a regular array structure in which (003) planes of the primary particles are oriented in a vertical direction with respect to the surface of the secondary particle.

New methods of producing aluminum fluoride from cryolite are disclosed. A method may include a step of reacting cryolite bath materials with aluminum sulfate, thereby producing a reactant product, the reactant product comprising aluminum fluoride. The method may further include a step of removing impurities from the reactant product, thereby creating a purified product comprising the aluminum fluoride. The removed impurities may comprise at least one of sodium (Na), magnesium (Mg), and calcium (Ca). In one embodiment, due to the removing step, the purified product contains not greater than 0.2 wt. % of calcium.

A positive active material precursor for a rechargeable lithium battery, a method for preparing a positive active material using the same, and a positive active material for a rechargeable lithium battery are provided. The positive active material precursor for a rechargeable lithium battery has a form of a core-shell particle including a core and a shell around the core, where the core includes a nickel-manganese-based composite hydroxide containing nickel and manganese, the shell includes a nickel-manganese-based composite hydroxide containing nickel, manganese, and a pillar element, and the pillar element includes at least one selected from Al, Mo, Ti, W, and Zr.

A positive-electrode active material for nonaqueous-electrolyte secondary batteries which comprises a given lithium-transition metal composite oxide haying a lamellar structure and a compound A containing Ca and/or Sr, the compound A being present on the surface of or at the boundaries of primary particles of the lithium-transition metal composite oxide. The lamellar structure includes an Li layer where Li reversibly goes in and out, and the proportion of non-lithium metallic element(s) present in the Li layer is 0.7-3.0 mol % with respect to the total amount of the non-lithium metallic elements contained in the lithium-transition metal composite oxide. In analysis by X-ray diffraction, the positive-electrode active material gives an X-ray diffraction pattern in which the ratio of the half-band width in of a diffraction peak for the (003) plane to the half-band width n of a diffraction peak for the (104) plane, m/n, is 0.7.5≤m/n≤1.0.

Disclosed is a hydrophilic carbon nanohorn aggregate comprising a carbon nanohorn aggregate having an oxygen-containing functional group introduced at a tip of a carbon nanohorn, and a cyclodextrin which is capping the tip of the carbon nanohorn and being stabilized.