The present invention relates to a positive electrode active material for a lithium secondary battery, and a lithium secondary battery including the same, and the positive electrode active material includes lithium cobalt oxide particles. The lithium cobalt oxide particles include lithium cobalt oxide having a Li/Co molar ratio of less than 1 in the particles. Good rate property and life property may be obtained without worrying on the deterioration of initial capacity property.

To provide a process for producing a cathode active material capable of obtaining a lithium ion secondary battery which has a high discharge capacity and a high initial efficiency, a cathode active material, a positive electrode for a lithium ion secondary battery, and a lithium ion secondary battery. A process for producing a cathode active material, which comprises a mixing step of mixing a lithium compound, an alkali metal compound other than Li, and a transition metal-containing compound containing at least Ni and Mn to obtain a mixture, a step of firing the mixture at a temperature of from 900 to 1,100° C. to obtain a first lithium-containing composite oxide containing the alkali metal other than Li, and a step of removing the alkali metal other than Li from the first lithium-containing composite oxide to obtain a second lithium-containing composite oxide represented by the following formula:
aLi(Li.sub.1/3Mn.sub.2/3)O.sub.2.Math.(1−a)LiMO.sub.2
wherein 0<a<1, and M is an element containing at least Ni and Mn.

A solid electrolyte material according to an aspect of the present disclosure is represented by the following Compositional Formula (1):
Li.sub.6-3zY.sub.zX.sub.6
where, 0<z<2 is satisfied; and X represents Cl or Br.

A mixed conductor represented by Formula 1:
A.sub.1±xM.sub.2±yO.sub.4−δ  Formula 1
wherein, in Formula 1, A is a monovalent cation, and M is at least one of a monovalent cation, a divalent cation, a trivalent cation, a tetravalent cation, a pentavalent cation, or a hexavalent cation, 0≤x≤1, 0≤y≤2, and 0≤δ≤1, with the proviso that when M includes vanadium, 0<δ≤1, and wherein the mixed conductor has an inverse spinel crystal structure.

This disclosure provides systems, methods, and apparatus related to inorganic halide perovskite nanowires. In one aspect, a first solution comprising cesium oleate or rubidium oleate in a first organic solvent is provided. A second solution comprising a lead halide and a surfactant in a second organic solvent is provided. The halide is selected from a group consisting of chlorine, bromine, and iodine. The first solution and the second solution are mixed. A reaction between the cesium oleate or the rubidium oleate and the lead halide forms a plurality of nanowires comprising an inorganic lead halide perovskite.

An electrode for a secondary battery comprises a current collector; and an active material-containing layer has active materials which comprise titanium-containing composite oxide having an orthorhombic crystal structure and represented by a general formula Li.sub.2+aM1.sub.2−bTi.sub.6−cM2.sub.dO.sub.14+δ; wherein the active material-containing layer has intensity ratio Ia/Ib in an X-ray diffraction pattern of the active material-containing layer, the Ia and the Ib are obtained by powder X-ray diffraction method using Cu-Kα ray, the intensity ratio is within a range of 0.5≤Ia/Ib≤2, the Ia is the strongest intensity of a diffraction peak among diffraction peaks appearing within a range of 42°≤2θ≤44°, and the Ib is the strongest intensity of a diffraction peak among diffraction peaks appearing within a range of 44°<2θ≤48°. (M1 is at least one selected from the group consisting of Sr, Ba, Ca, Mg, Na, Cs, Rb and K, M2 is at least one selected from the group consisting of Zr, Sn, V, Nb, Ta, Mo, W, Y, Fe, Co, Cr, Mn, Ni and Al a is within a range of 0≤a≤6 b is within a range of 0≤b<2 c is within a range of 0≤c<6 d is within a range of 0≤d<6 δ is within a range of −0.5≤δ≤0.5.)

A compound of formula Li.sub.4+xMnM.sup.1.sub.aM.sup.2.sub.bO.sub.c wherein: M.sup.1 is selected from the group consisting in Ni, Mn, Co, Fe and a mixture thereof; M.sup.2 is selected from the group consisting in Si, Ti, Mo, B, Al and a mixture thereof;
with: −1.2≦x≦3; 0<a≦2.5; 0≦b≦1.5; 4.3≦c≦10; and c=4+a+n.Math.b+x/2
wherein n=2 when M.sup.2 is selected from the group consisting in Si, Ti, Mo or a mixture thereof; and n=1.5 when M.sup.2 is selected from the group consisting in B, Al or a mixture thereof; and n=0 if b=0.

This disclosure will describe a novel finding and make the claim for the first time on a group of old compounds and formulated new compounds. These compounds have superconducting property at high temperatures, i.e., 151K or higher. Several compounds were prepared, though not well-purified, at around middle of 1900s. Their chemical, structural, electric and magnetic properties were studied and reported but their superconducting property has not been known and has never been exploited because the idea of type-II superconductivity was not proposed at that time. Consequently, we claim this finding as an invention even though our invention is based on the studies of the compounds' electric and magnetic properties along with their crystallographic features from the previous publications. The experiments to further verify their high temperature superconductivity require the utilization of sophisticated facilities on synthesizing highly pure compounds and the deregulation from government security authorities on purchasing the starting materials.

A sintered ferrite magnet comprising (a) a ferrite phase having a hexagonal M-type magnetoplumbite structure comprising Ca, an element R which is at least one of rare earth elements and indispensably includes La, an element A which is Ba and/or Sr, Fe, and Co as indispensable elements, the composition of metal elements of Ca, R, A, Fe and Co being represented by the general formula of Ca.sub.1-x-yR.sub.xA.sub.yFe.sub.2n-zCo.sub.z, wherein the atomic ratios (1-x-y), x, y and z of these elements and the molar ratio n meet the relations of 0.3≦(1-x-y)≦0.65, 0.2≦x≦0.65, 0≦y≦0.2, 0.03≦z≦0.65, and 4≦n≦7, and (b) a grain boundary phase indispensably containing Si, the amount of Si being more than 1% by mass and 1.8% or less by mass (calculated as SiO.sub.2) based on the entire sintered ferrite magnet, and its production method.

According to one embodiment, there is provided an active substance. The active substance includes secondary particles and a carbon material phase formed on at least a part of a surface of each of the secondary particles. Each of the secondary particles is constructed by aggregated primary particles of an active material. The primary particles of the active material includes a niobium composite oxide represented by Li.sub.xM.sub.(1−y)Nb.sub.yNb.sub.2O.sub.(7+δ), wherein M is at least one selected from the group consisting of Ti and Zr, and x, y, and δ respectively satisfy 0≦x≦6, 0≦y≦1, and −1≦δ≦1. The secondary particles have a compression fracture strength of 10 MPa or more.