A positive electrode active material for a non-aqueous electrolyte secondary battery contains a lithium-nickel-manganese-containing composite oxide which is represented by composition formula Li.sub.xNi.sub.yMn.sub.zMe.sub.1-y-zO.sub.2 (where Me is a metal element other than Li, Ni, and Mn, x≤1.16, 0.3≤y≤0.7, and 0.3≤z≤0.7), has a layered structure belonging to space group R-3m, and has a diffraction peak at 2θ in the range of greater than or equal to 65° and less than or equal to 67° in an X-ray diffraction pattern when charging and discharging are performed until the charge voltage reaches 4.8 V.

The present invention provides a positive electrode active material precursor for a lithium secondary battery, in which the positive electrode active material precursor is represented by the following composition formula (I), a ratio (α/β) between a half width α of a peak that is present within a range of a diffraction angle 2θ=19.2±1° and a half width β of a peak that is present within a range of 2θ=38.5±1° is equal to or greater than 0.9 in powder X-ray diffraction measurement using a CuKα beam:
Ni.sub.xCo.sub.yMn.sub.zM.sub.w(OH).sub.2  (I)
[0.7≤x<1.0, 0<y≤0.20, 0≤z≤0.20, 0≤w≤0.1, and x+y+z+w=1 are satisfied, and M is one or more selected from the group consisting of Mg, Ca, Sr, Ba, Ti, Zr, V, Nb, Cr, Mo, W, Fe, Ru, Cu, Zn, B, Al, Ga, Si, Sn, P, and Bi].

An improved method of forming a transition metal layered oxide material for alkali-ion battery cathodes include combining an alkali-containing precursor and at least one transition metal precursor or other metal precursor at a low temperature of less than 100° C. to form a liquid eutectic alloy mixture. The mixture is then heated at a temperature between 300° C. to 500° C. to pre-calcinate the mixture, and subsequently the pre-calcinated mixture is subjected to a final calcination at a temperature of 500° C. to 1000° C. to obtain a crystalline oxide material. A P2-type or O3-type cathode may be formed with the layered oxide material, and a sodium-ion battery cell may include the so-formed P2-type or O3-type cathode.

The present invention relates to sheet silicate lamellae of a 2:1 sheet silicate with a high aspect ratio, to a method for producing these sheet silicate lamellae and to an aqueous dispersion which comprises the sheet silicate lamellae. The present invention further relates to the use of the sheet silicate lamellae of the invention for producing a composite material, and also to a corresponding composite material comprising or obtainable using the sheet silicate lamellae, more particularly for use as a diffusion barrier or as a flame retardant.

A lithium metal composite oxide powder having a layered structure and containing at least Li, Ni, and an element X, in which, in a cumulative frequency distribution curve of R ranging 0% to 100% as a whole, R(90) that is a value of R at a point where a cumulative frequency from a small side of the R reaches 90% is 1.7 or more and 3.7 or less. R is a value of O/(Ni+X) that is a ratio of an amount of a substance of oxygen, which is indicated by O, to a total amount of substances of nickel and the element X, which is indicated by Ni+X, in one particle of a lithium metal composite oxide that is contained in the lithium metal composite oxide powder. The amounts of the substances of nickel, the element X, and oxygen are obtained by energy-dispersive X-ray (EDX) spectroscopy in which an accelerating voltage is set to 1100 V regarding the one particle of the lithium metal composite oxide.

A lithium metal composite oxide powder having a layered structure, containing at least Li, Ni, an element X, and an element M, in which the element X is one or more elements selected from the group consisting of Co, Mn, Fe, Cu, Ti, Mg, Al, W, Mo, Nb, Zn, Sn, Zr, Ga, and V, the element M is one or more elements selected from the group consisting of B, Si, S, and P, M/(Ni+X) that is a content ratio of the element M to a total amount of Ni and the element X that are contained in the lithium metal composite oxide powder is 0.01 mol % or more and 5 mol % or less, Ni/(Ni+X) that is a content ratio of Ni to the total amount of Ni and the element X that are contained in the lithium metal composite oxide powder satisfies 0.40 or more in terms of a mole ratio, and a ratio of the element M eluted into N-methyl-2-pyrrolidone measured under specific measurement conditions is 0.09 or less.

A stabilized lithium metal oxide cathode material comprises microparticles of lithium metal oxide in which individual particles thereof a core of lithium metal oxide and a coating of a different lithium metal oxide surrounding the core. There is an interface layer between the cores and the coatings in which there are gradients of metal ions in the direction of coating to core. The materials are made by a three stage process involving coprecipitating precursor metal hydroxide core particles at a controlled pH; coprecipitating a different metal hydroxide coating on the particles without controlling the pH; and then calcining the resulting coated precursor particles with lithium hydroxide to form the stabilized lithium metal oxide material.

A nano-thin Bi.sub.xO.sub.ySe.sub.z low-temperature oxygen transporter membrane for oxygen transport, separation, and two-dimensional (2D) material manipulation comprising a material comprising a compound of Bi.sub.xO.sub.ySe.sub.z and R3m bismuth oxide (Bi.sub.2O.sub.3). A method of making a nano-thin Bi.sub.xO.sub.ySe.sub.z low-temperature oxygen transporter membrane for oxygen transport, separation, and two-dimensional (2D) material manipulation comprising providing an oxygen environment, providing Bi.sub.2Se.sub.3, processing the Bi.sub.2Se.sub.3 in the oxygen environment, incorporating oxygen, removing selenium, creating a structural change, and creating a compound of Bi.sub.xO.sub.ySe.sub.z and R3m bismuth oxide (Bi.sub.2O.sub.3), wherein the material transports oxygen at room temperature.

A quantum dot including a nanoparticle template including a first semiconductor nanocrystal including a Group II-VI compound, a quantum well including a second semiconductor nanocrystal disposed on the nanoparticle template, the second semiconductor nanocrystal including a Group IIIA metal excluding aluminum and a Group V element; and a shell comprising a third semiconductor nanocrystal disposed on the quantum well, the third semiconductor nanocrystal including a Group II-VI compound, wherein the quantum dot does not include cadmium, a band gap energy of the second semiconductor nanocrystal is less than a band gap energy of the first semiconductor nanocrystal, the band gap energy of the second semiconductor nanocrystal is less than a band gap energy of the third semiconductor nanocrystal, and the quantum dot includes an additional metal including an alkali metal, an alkaline earth metal, aluminum, iron, cobalt, nickel, copper, zinc, or a combination thereof.

Li-rich transition metal oxides material, useful as cathode for Li-ion batteries and having general formula Li.sub.1.2+xMn.sub.0.54Ni.sub.0.13Co.sub.0.13-x-yAl.sub.yO.sub.2; where: 0.01≤x≤0.1; 0.01≤y≤0.1; and 0.03≤x+y<0.13.