Provided is a new 5 V-class spinel-type lithium-manganese-containing composite oxide capable of achieving both the expansion of a high potential capacity region and the suppression of gas generation. Proposed is the spinel-type lithium-manganese-containing composite oxide comprising Li, Mn, O and two or more other elements, and having an operating potential of 4.5 V or more at a metal Li reference potential, wherein a peak is present in a range of 14.0 to 16.5° at 2θ, in an X-ray diffraction pattern measured by a powder X-ray diffractometer (XRD) using CuKα1 ray.

Provided is a new 5 V class spinel-type lithium manganese-containing composite oxide which enables the expansion of a high potential capacity region and the suppression of gas generation. The 5 V class spinel-type lithium manganese-containing composite oxide has an operating potential of 4.5 V or more at a metal Li reference potential, and contains Li, Mn, O and two or more other elements. The spinel-type lithium manganese-containing composite oxide is characterized in that, in an electronic diffraction image from a transmission electron microscope (TEM), a diffraction spot observed in the Fd-3m structure as well as a diffraction spot not observed in the Fd-3m structure are confirmed.

There is provided a Co-based 5-V spinel-type lithium manganese-containing complex oxide not only having an operating potential of 4.5 V or higher but also being capable of extending its capacity region of a 5.5 to 5.5 V region and being capable of enhancing its energy density as well. There is proposed a spinel-type lithium cobalt manganese-containing complex oxide having a crystal structure classified as a space group Fd-3m and being represented by the general formula [Li.sub.x(Co.sub.yMn.sub.3−x−y)O.sub.4−δ] (wherein 0.90≦x≦1.15 and 0.75≦y≦1.25), wherein the oxide has a crystallite size measured by a Rietveld method using the fundamental method of 100 nm to 200 nm, an interatomic distance of Li—O of 1.80 Å to 2.00 Å, and a strain of 0.20 to 0.50.

The present disclosure relates to a cathode active material, and more particularly, to a cathode active material doped with a trivalent metal (Me) and a lithium secondary battery comprising the same. According to one aspect, there is provided the cathode active material doped with the trivalent metal (Me), represented by the formula Li.sub.xMn.sub.2Me.sub.yO.sub.4 (here, x is from 0.5 to 1.3, and y is from 0.01 to 0.1). According to the present disclosure, release of manganese ions of the cathode active material greatly reduces, and consequently, capacity and cycle life of the battery may be significantly improved.

The present invention provides a precursor of positive electrode active substance particles for non-aqueous electrolyte secondary batteries which have a high discharge voltage and a high discharge capacity, hardly suffer from side reactions with an electrolyte solution, and are excellent in cycle characteristics, positive electrode active substance particles for non-aqueous electrolyte secondary batteries, and processes for producing these particles, and a non-aqueous electrolyte secondary battery. The present invention relates to positive electrode active substance particles for non-aqueous electrolyte secondary batteries having a spinel structure with a composition represented by the following chemical formula (1), in which the positive electrode active substance particles satisfy the following characteristic (A) and/or characteristic (B) when indexed with Fd-3m in X-ray diffraction thereof: (A) when indexed with Fd-3m in X-ray diffraction of the positive electrode active substance particles, a ratio of I(311) to I(111) [I(311)/I(111)] is in the range of 35 to 43%, and/or (B) when indexed with Fd-3m in X-ray diffraction of the positive electrode active substance particles, a gradient of a straight line determined by a least square method in a graph prepared by plotting sin θ in an abscissa thereof and B cos θ in an ordinate thereof wherein B is a full-width at half maximum with respect to each peak position 2θ (10 to 90°) is in the range of 3.0×10.sup.−4 to 20.0×10.sup.−4; and
Li.sub.1+xMn.sub.2−y−zNi.sub.yM.sub.zO.sub.4  Chemical Formula (1)
wherein x, y, z fall within the range of −0.05.Math.x.Math.0.15, 0.4.Math.y.Math.0.6 and 0.Math.z.Math.0.20, respectively; and M is at least one element selected from the group consisting of Mg, Al, Si, Ca, Ti, Co, Zn, Sb, Ba, W and Bi.

Provided is a novel positive electrode active material capable of suppressing resistance and improving rate characteristics and cycle characteristics while enhancing lithium ionic conductivity, wherein the surface of particles composed of a spinel-type composite oxide containing Li, Mn, O, and two or more other elements is coated with a lithium ion conductive oxide such as LiNbO.sub.3. Proposed is a positive electrode active material for an all-solid-type lithium secondary battery, wherein the surface of present core particles composed of a spinel-type composite oxide containing Li, Mn, O, and two or more other elements is coated with an amorphous compound containing Li, A (A represents one or more elements selected from the group consisting of Ti, Zr, Ta, Nb, and Al), and O; and the molar ratio (Li/A) of Li relative to the A element in the surface, as obtained by XPS, is 1.0 to 3.5.

A process for preparing a stable Group VIII Period 4 element (iron, cobalt, or nickel) B site and chlorine O site modified lithium manganese-based AB.sub.2O.sub.4 spinel cathode material is provided. The general formula of the B and O site modified lithium manganese-based AB.sub.2O.sub.4 spinel is LixMn.sub.2-yM.sub.yO.sub.4-z(Cl.sub.z) where M is Fe, Co or Ni. In addition, a Group VIII Period 4 element (iron, cobalt, or nickel) B site and chlorine O site modified lithium manganese-based AB.sub.2O.sub.4 spinel cathode material is provided. Furthermore, a lithium or lithium ion rechargeable electrochemical cell is provided, incorporating the Group VIII Period 4 element (iron, cobalt, or nickel) B site and chlorine O site modified lithium manganese-based AB.sub.2O.sub.4 spinel cathode material in a positive electrode.

Provided is a new 5 V class spinel-type lithium manganese-containing composite oxide which enables the expansion of a high potential capacity region and the suppression of gas generation. The 5 V class spinel-type lithium manganese-containing composite oxide has an operating potential of 4.5 V or more at a metal Li reference potential, and contains Li, Mn, O and two or more other elements. The spinel-type lithium manganese-containing composite oxide is characterized in that, in an electronic diffraction image from a transmission electron microscope (TEM), a diffraction spot observed in the Fd-3m structure as well as a diffraction spot not observed in the Fd-3m structure are confirmed.

Provided is a novel positive electrode active material capable of suppressing resistance and improving rate characteristics and cycle characteristics while enhancing lithium ionic conductivity, wherein the surface of particles composed of a spinel-type composite oxide containing Li, Mn, O, and two or more other elements is coated with a lithium ion conductive oxide such as LiNbO.sub.3. Proposed is a positive electrode active material for an all-solid-type lithium secondary battery, wherein the surface of present core particles composed of a spinel-type composite oxide containing Li, Mn, O, and two or more other elements is coated with an amorphous compound containing Li, A (A represents one or more elements selected from the group consisting of Ti, Zr, Ta, Nb, and Al), and O; and the molar ratio (Li/A) of Li relative to the A element in the surface, as obtained by XPS, is 1.0 to 3.5.

A manufacturing method of a cathode active material for lithium secondary battery, including: preparing a first solution by mixing a metal oxide and a solvent; preparing a metal-mixed solution by adding an acidic solution to the first solution and then applying ultrasonic waves to the mixture; centrifuging the metal-mixed solution; preparing a second solution by mixing a supernatant of the centrifuged metal-mixed solution, a reductant, and a solvent and then applying ultrasonic waves to the mixture; obtaining powder by filtering and then drying the second solution; forming mesoporous spherical nanoparticles by mixing the powder, a metal, a lithium precursor, and a solvent, applying ultrasonic waves to the mixture and then drying the mixture; and performing a heat treatment to the spherical nanoparticles, and a cathode active material for a lithium secondary battery obtained by the manufacturing method. The cathode active material for lithium secondary battery is mesoporous spherical nanoparticles.