A sodium-containing oxide positive electrode material and a preparation method therefor and use thereof are disclosed. Also disclosed are a positive electrode plate and uses thereof.

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 2, in an X-ray diffraction pattern measured by a powder X-ray diffractometer (XRD) using CuK1 ray.

The present invention relates to a method of preparing a positive electrode active material for a lithium secondary battery and the positive electrode active material for the lithium secondary battery prepared thereby, and more specifically, to a method of preparing a positive electrode active material for a lithium secondary battery, the method comprising doping or coating the positive electrode active material for the lithium secondary battery with a predetermined metal oxide, and the positive electrode active material for the lithium secondary battery which is prepared thereby and has a reduced amount of residual lithium.

An objective of the present invention is to provide a positive electrode active material that can inhibit the capacity changes associated with temperature variations, and an alkaline battery that contains this positive electrode active material. Aluminum and ytterbium are at least partially solid-dissolved in nickel hydroxide in the nickel composite hydroxide present in the positive electrode active material of the present invention.

Provided are a method of preparing a positive electrode active material for a secondary battery, in which the positive electrode active material is uniformly doped with various doping elements without worrying about surface damage of the active material and characteristics degradation by including mixing a metal precursor for a positive electrode active material and a raw material including a doping element, in which an average particle diameter ratio is in a range of 5:1 to 2,000:1, using acoustic resonance to prepare a precursor doped with the doping element, and mixing the doped precursor with a lithium raw material and performing a heat treatment, and a positive electrode active material which has improved structure stability by being prepared by the above method and may improve battery characteristics, for example, capacity reduction may be minimized and cycle characteristics may be improved when used in the battery.

In a perovskite-type composite oxide powder according to the present invention, the geometric standard deviation value of the maximum Feret diameter of the perovskite-type composite oxide powder calculated by performing image analysis on an SEM image acquired with a scanning electron microscope is equal to or greater than 1.01 and less than 1.60, and when it is assumed that the perovskite-type composite oxide powder is spherical, the ratio (B/A) of an area value B directly calculated by the image analysis to an area value A calculated from the maximum Feret diameter is equal to or greater than 0.7 and less than 1.0. In this way, the perovskite-type composite oxide powder is used as the air electrode material of an SOFC, and thus high conductivity as compared with a conventional air electrode material is obtained.

Disclosed is a catalyst having a perovskite structure in the form of ABO.sub.3, in which the number of ion moles at the A site has an excess ratio compared to the number of ion moles at the B site. The present invention exhibits an oxygen catalytic activity improved by about 3 times in an oxygen evolution reaction and by about 40% in an oxygen reduction reaction, compared to those of an existing LaNiO.sub.3 perovskite catalyst. Further, since the metallic conductivity is not significantly changed compared to the existing LaNiO.sub.3 perovskite oxide, there is an advantage in that a carbon support need not be used when the present invention is used as a catalyst in a battery positive electrode.

A positive electrode active material includes secondary particles. The secondary particles include a plurality of primary particles. The primary particles include a lithium-containing composite metal oxide. Inside the secondary particles, an electron conducting oxide is disposed at at least a part of a grain boundary between the primary particles. The electron conducting oxide has a perovskite structure.

The present invention provides a positive electrode active material for a secondary battery, the positive electrode active material including a lithium composite metal oxide particle represented by Formula 1 below, and a secondary battery including the same.

Li.sub.aNi.sub.1?x?yCo.sub.xM1.sub.yM2.sub.zM3.sub.wO.sub.2[Formula 1]

In Formula 1,

M1 is a metal element whose surface energy (?E.sub.surf) calculated by Equation 1 below is ?0.5 eV or higher, M2 is a metal element whose surface energy (?E.sub.surf) calculated by Equation 1 below is ?1.5 eV or higher and less than ?0.5 eV, M3 is a metal element whose surface energy (?E.sub.surf) calculated by Equation 1 below is less than ?1.5 eV, and 1.0?a?1.5, 0<x?0.5, 0<z?0.05, 0.002?w?0.1, 0<x+y?0.7.

[00001]$\begin{array}{cc}\begin{array}{c}?.Math..Math.E_{\mathrm{surf}}=.Math.E_{\mathrm{surf}.Math..Math.2}-E_{\mathrm{surf}.Math..Math.1}\\ =.Math.\left(E_{\mathrm{slab}.Math..Math.2}-E_{\mathrm{bulk}}\right)-\left(E_{\mathrm{slab}.Math..Math.1}-E_{\mathrm{bulk}}\right)\end{array}& \left[\mathrm{Equation}.Math..Math.1\right]\end{array}$

In Equation 1 above, E.sub.surf2 represents an extent to which a metal element is oriented toward the outermost surface of the lithium composite metal oxide particle, E.sub.surf1 represents an extent to which the metal element is oriented toward a central portion of the lithium co

An alkaline electrochemical cell component includes a bulk portion and a surface portion including a conductive, electrochemically and chemically stable material having one or more compounds of formula (I): La(Ni.sub.1-xCu.sub.x)O.sub.3 (I), where 0<=x<=1, the electrochemical cell having a pH>7.