The present invention comprises: an overlithiated layered oxide represented by chemical formula 1 below; and an ion-conductive coating layer on the overlithiated layered oxide represented by chemical formula 1: [chemical formula 1] .sub.rLi.sub.2MnO.sub.3.Math.(1-r)Li.sub.aNi.sub.xCo.sub.yMn.sub.zM1.sub.1−(x+y+z)O.sub.2 (in chemical formula 1, 0<r≤0.6, 0<a≤1, 0≤x≤1, 0≤y<1, 0≤z<1, and 0<x+y+z<1, and M1 is at least one selected from among Na, K, Mg, Al, Fe, Cr, Y, Sn, Ti, B, P, Zr, Ru, Nb, W, Ba, Sr, La, Ga, Mg, Gd, Sm, Ca, Ce, Fe, Al, Ta, Mo, Sc, V, Zn, Cu, In, S, B, Ge, Si, and Bi).

Single-phase manganese oxide particles having a wurtzite crystal structure. The particles can be obtained by thermally decomposing a compound containing manganese. In this procedure, a reducing agent consisting of at least one of a polyol-based material and an ethylene glycol stearate-based material is added as an additive to the reaction system. It is heated at a first temperature (200° C. or lower) under a reduced pressure atmosphere, then the temperature is raised, and the product is heated at a temperature higher than the first temperature under an inert gas atmosphere.

A graphite anode material, an anode, a lithium ion battery and preparation methods thereof. The graphite anode material includes a natural graphite core, a carbon coating layer, and a graphitizing filler. The natural graphite core has pores. The graphitizing filler is filled in the pores inside the natural graphite core. The graphitizing filler further forms the carbon coating layer. The preparation method includes: mixing natural graphite with a filler, and then pulverizing to obtain a graphite powder body; and graphitizing the graphite powder body in a protective atmosphere to obtain a graphite anode material. The preparation method reduces material turnover and residual loss, and achieves simple process and high production efficiency. The anode and lithium ion battery prepared have high first efficiency and excellent cycling performance.

A composite cathode active material, a method of preparing the composite cathode active material, and a lithium secondary battery including a cathode including the composite cathode active material are provided. The composite cathode active material includes: a nickel-based active material including about 60 mol % or more of nickel; and a coating layer on a surface of the nickel-based active material, the coating layer including a lanthanide composite. The composite cathode active material includes or is in the form of single crystal particles having an average particle diameter in a range of about 2 μm to about 8 μm.

A method of producing a magnetic powder includes: performing heat treatment on first particles that contain triiron tetraoxide to prepare second particles that contain ε-iron oxide.

A positive electrode active material for a lithium ion battery comprises a lithium transition metal-based oxide powder, the powder comprising single crystal monolithic particles comprising Ni and Co and having a general formula Li.sub.1+a (Ni.sub.z Mn.sub.y Co.sub.x Zr.sub.q A.sub.k).sub.1−a O.sub.2, wherein A is a dopant, −0.025≤a<0.005, 0.60≤z≤0.95, y≤0.20, 0.05≤x≤0.20, k≤0.20, 0≤q≤0.10, and x+y+z+k+q=1. The particles have a cobalt concentration gradient wherein the particle surface has a higher Co content than the particle center.

An advantage is to provide a non-aqueous electrolyte secondary battery with improved heat resistance. A positive electrode active material contains a lithium-transition metal composite oxide containing 80 mol % or more of Ni and 0.1 mol % to 1.5 mol % of B on the basis of the total number of moles of metal elements excluding Li, and B and at least one element (M1) selected from Groups 4 to 6 are present on at least the surfaces of particles of the composite oxide. When particles having a volume-based particle size larger than 70% particle size (D70) are first particles, and particles having a volume-based particle size smaller than 30% particle size (D30) are second particles, the molar fraction of M1 on the basis of the total number of moles of metallic elements excluding Li on the surfaces of the second particles is greater than that of the first particles.

A process for producing a surface-modified particulate lithium nickel metal oxide material is provided. The process comprises the addition of a controlled quantity of a coating liquid to lithium nickel metal oxide particles followed by a calcination step.

A positive electrode active material for a non-aqueous electrolyte secondary battery, according to an example of this embodiment, includes a lithium transition metal composite oxide which has a layered structure and contains at least Ni, Al, and Ca. The lithium transition metal composite oxide has a Ni content of 85-95 mol %, an Al content of at most 8 mol %, and a Ca content of at most 2 mol % with respect to the total amount of metal elements other than Li. In addition, the proportion of metal elements other than Li present in a Li layer is 0.6-2.0 mol % with respect to the total amount of metal elements other than Li contained in the composite oxide.

A cathode active material for a lithium secondary battery includes a core portion comprising a lithium metal oxide particle, and a coating layer at least partially covering a surface of the core portion and including a lithium boron composite oxide. The lithium boron composite oxide is included in an amount from 100 ppm to 1,500 ppm based on a total weight of the cathode active material. A lithium secondary battery having improved structural stability and electrical property is provided using the cathode active material.