An aligned film having first and second faces opposed to each other, the aligned film having (a) a plurality of layers aligned non-parallel to the first and second faces between the faces of the aligned film, each layer having a crystal lattice represented by: M.sub.n+1X.sub.n (wherein M is at least one metal of Group 3, 4, 5, 6, or 7; X is a carbon atom, a nitrogen atom, or a combination thereof; and n is 1, 2, or 3), each X is positioned within an octahedral array of M, and at least one of two opposing surfaces of each said layer have at least one modifier or terminal T selected from a hydroxy group, a fluorine atom, an oxygen atom, and a hydrogen atom; and (b) magnetic nanoparticles carried on a layer surface and/or between two adjacent layers of the plurality of layers.

The present disclosure generally relates to compositions comprising substrate-free crystalline 2D bismuthene, and the method of making and using the substrate-free crystalline 2D bismuthene.

The present application discloses positive electrode active material, preparation method thereof, positive electrode plate, lithium-ion secondary battery and battery module, pack, and apparatus. The positive electrode active material includes a nickel-containing lithium composite oxide satisfying a chemical formula Li.sub.1+a[Ni.sub.xCo.sub.yMn.sub.zM.sub.b]O.sub.2, in the formula, M is a doping element at transition metal site, 0.5≤x<1, 0≤y<0.3, 0≤z<0.3, −0.1≤a<0.2, 0<b<0.3, x+y+z+b=1, wherein the positive electrode active material has a layered crystal structure and belongs to space group R3m; under the condition that the positive electrode active material is in 78% delithiation state, at least part of the doping elements M have a chemical valence of +3 or more, and surface oxygen of the positive electrode active material has an average valence state of V.sub.O satisfying −2.0≤V.sub.O≤−1.5.

A lithium metal composite oxide composed of secondary particles that are aggregates of primary particles, and single particles that exist independently from the secondary particles, wherein the lithium metal composite oxide is represented by a compositional formula (1), and satisfies requirements (A), (B) and (C).

The present invention relates to an electrode active material for a sodium secondary battery, including: a composite metal oxide, in which the composite metal oxide is represented by Formula (1), and in a case where a peak intensity of a (200) plane of nickel oxide which is observed in the vicinity of 43° of a powder X-ray diffraction spectrum is set as I, and a peak intensity of a (104) plane of the composite metal oxide represented by Formula (1) which is observed in the vicinity of 41° to 42.5° is set as I.sub.0, I/I.sub.0 obtained by dividing I by I.sub.0 is 0.2 or less.

Provided are an atomic layer sheet that contains boron and oxygen as framework elements, is networked by nonequilibrium couplings having boron-boron bonds, and has a molar ratio of oxygen to boron (oxygen/boron) of less than 1.5, a laminated sheet containing a plurality of such atomic layer sheets and metal ions between ones of the sheets, and a thermotropic liquid crystal and a lyotropic liquid crystal containing these. In addition, there is provided a method for manufacturing an atomic layer sheet and/or a laminated sheet containing boron and oxygen, the method including: adding MBH.sub.4, where M represents an alkali metal ion, into a solvent containing an organic solvent in an inert gas atmosphere to prepare a solution; and exposing the solution to an atmosphere containing oxygen.

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.

Provided are a metal element-doped positive electrode active material for a high voltage and a preparation method thereof. The positive electrode active material may include a lithium cobalt oxide having a layered crystal structure; and a metal element (M) incorporated into the lithium cobalt oxide in an amount of 0.2 parts by weight to 1 part by weight with respect to 100 parts by weight of the lithium cobalt oxide, wherein the metal element (M) does not form a chemical bond with the elements of the lithium cobalt oxide, and wherein the layered crystal structure in maintained at a positive electrode potential of more than 4.5 V (based on Li potential) when fully charged.

Methods for synthesizing single crystalline Ni-rich cathode materials are disclosed. The Ni-rich cathode material may have a formula LiNi.sub.XMn.sub.yM.sub.zCo.sub.1-x-y-zO.sub.2, where M represents one or more dopant metals, x≥0.6, 0.01≤y<0.2, 0≤z≤0.05, and x+y+z≤1.0. The methods are cost-effective, and include methods for solid-state, molten-salt, and flash-sintering syntheses.

Provided is a method for producing a positive electrode active material for nonaqueous electrolyte secondary batteries, the method including: a mixing step of obtaining a W-containing mixture of Li metal composite oxide particles represented by the formula: Li.sub.zNi.sub.1-x-yCO.sub.xM.sub.yO.sub.2 and composed of primary particles and secondary particles formed by aggregation of the primary particles, 2 mass % or more of water with respect to the oxide particles, and a W compound or a W compound and a Li compound, the W-containing mixture having a molar ratio of the total amount of Li contained in water and the solid W compound or the W compound and the Li compound of 3 to 5 with respect to the amount of W contained therein; and a heat treatment step of heating the W-containing mixture to form lithium tungstate on the surface of the primary particles of the Li metal composite oxide particles.