Disclosed herein are compositions comprising zirconium and cerium having a surprisingly small particle sizes. The compositions disclosed herein contain zirconium, cerium, optionally yttrium, and optionally one or more rare earths other than cerium and yttrium The compositions exhibit a particle size characterized by a Dso value of about 20 μm to about 45 μm and a D.sub.99 value of about 55 μm to about 1 00 μm. Further disclosed are processes of producing these compositions using oxalic acid in the process. The compositions can be used as a catalyst and/or part of a catalytic system for automobile exhaust gas.

The present document describes an oral care composition comprising a cuttlefish bone powder, comprising particles having more than 95% (w/w) calcium carbonate content, a specific surface area of at least 5 m.sup.2/g, a mechanical hardness about 4.75 to 6.87 GPa, and at least 20% of said particles of the powder have a particle size of from about 50 microns to about 70 microns and a mean of about 60 microns, and a suitable carrier, and uses of the composition for oral hygiene.

Provided are a zirconia sol having a transmittance of 45% or more at a wavelength of 400 nm, having a transmittance of 75% or more at a wavelength of 550 nm, and containing zirconia particles in an amount of 20 wt % or more, and a method for manufacturing the zirconia sol.

A negative electrode material for a lithium-ion secondary battery includes composite particles, each of the composite particles having a structure in which plural flat graphite particles are stacked, wherein the composite particles have a particle size distribution D90/D10 of from 2.0 to 5.0, or wherein the plural flat graphite particles have a particle size distribution D90/D10 of from 2.0 to 4.4.

A positive electrode active material precursor has a hydroxide represented by Formula 1, wherein the positive electrode active material precursor is a secondary particle, in which a plurality of primary particles are aggregated, and includes crystallines in which major axes of the primary particles are arranged in a direction from a center of the secondary particle toward a surface thereof and a (001) plane of the primary particle is arranged parallel to the major axis of the primary particle. A method of preparing the positive electrode active material precursor, and a positive electrode active material prepared by using the positive electrode active material precursor are also provided.

A method for preparing ternary positive material in a lithium battery includes mixing nickel salt, cobalt salt, and manganese salt to form a mixed solution. A precipitant and a complexing agent are added into the mixed solution, thereby adjusting a pH value to a range of 10.5 to 12 and obtaining a precursor A. The precursor A and lithium salt are ground by a ball mill to obtain a precursor B, precursor B then being sintered in an air or oxygen atmosphere. The sintering includes heating at a first heating speed of 5 to 15° C./min to a first temperature of 400 to 800° C. and being held at such temperature for 1 to 6 h, and heating at a second heating speed of 1 to 10° C./min to a second temperature of 900 to 980° C. and being held there for 8 to 10 h.

A method of preparing a bimodal positive electrode active material precursor and a positive electrode active material prepared from the same are disclosed herein. In some embodiments, the method includes inputting a first reaction source material including a first aqueous transition metal solution into a reactor, precipitating at pH 12 or more to induce nucleation of a first positive electrode active material precursor particle, and at less than pH 12 to induce growth of the same, inputting a second reaction source material including a second aqueous transition metal solution into the reactor containing the first positive electrode active material precursor particle, precipitating at pH 12 or more to induce the nucleation of a second positive electrode active material precursor particle, and at less than pH 12 to induce simultaneous growth of the first and second positive electrode active material precursor particles, thereby preparing a bimodal positive electrode active material precursor.

A method for preparing a positive electrode active material and a positive electrode active material prepared by the method are provided. The method includes preparing a lithium composite transition metal oxide represented by Formula 1, and washing the lithium composite transition metal oxide with a cleaning liquid containing cleaning water and a surfactant. The cleaning liquid contains cleaning water in an amount of no less than 50 parts by weight and less than 400 parts by weight based on 100 parts by weight of the lithium composite transition metal oxide.

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) thermally treating a positive electrode scrap comprising an active material layer comprising nickel, cobalt and manganese on a current collector in air for thermal decomposition of a binder and a conductive material in the active material layer, to separate the current collector from the active material layer, and collecting an active material in the active material layer, (b) washing the active material collected form the step (a) 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 an addition of a lithium precursor to obtain a reusable active material.

Provided are a cathode active material for a lithium secondary battery, a method of preparing the same, and a lithium secondary battery containing a cathode including the cathode active material, in which the cathode active material includes nickel-based lithium metal oxide containing single-crystal particles, and a particle size of the single-crystal particles is about 1 μm to about 8 μm, and a particle size distribution of the single-crystal particles expressed by (D90-D10)/D50 is 1.4 or less.