This disclosure provides systems, methods, and apparatus related to lithium-ion batteries. In one aspect, a method includes synthesizing an intermediate selected from a group of a nickel-manganese-cobalt nitrate, a nickel-manganese-cobalt acetate, a nickel-manganese-cobalt sulfate, a nickel-manganese-cobalt chloride, and a nickel-manganese-cobalt phosphate. The intermediate is mixed with a lithium salt selected from a group of LiOH, LiCl, LiNO.sub.3, LiSO.sub.4, LiF, LiBr, Li.sub.3PO.sub.4, Li.sub.2CO.sub.3, and combinations thereof to form a mixture. The mixture is annealed at a sequence of temperatures and times to form a plurality of single crystals of a lithium nickel-manganese-cobalt oxide, with no cooling of the mixture between operations of the sequence of temperatures and times.

The present disclosure provides a cobalt-free cathode material of a lithium ion battery, a method for preparing the cobalt-free cathode material, and the lithium ion battery. A general formula of the cobalt-free cathode material is Li.sub.xNi.sub.aMn.sub.bR.sub.cO.sub.2, wherein, 1≤x≤1.15, 0.5≤a≤0.95, 0.02≤b≤0.48, 0<c≤0.05, and R is aluminum or tungsten. Therefore, as the cobalt-free cathode material is free of metal cobalt, the cost of the cathode material can be lowered effectively. Aluminum or tungsten in the cobalt-free cathode material can stabilize a crystal structure of the cathode material better, such that the lithium ion battery has excellent rate capability and cycle performance, and furthermore, good cycling stability of the lithium ion battery can be still maintained under a high-temperature and high-pressure testing condition.

The present exemplary embodiments relate to a cathode active material, a manufacturing method thereof, and a lithium secondary battery including the same. A cathode active material according to an exemplary embodiment is a lithium metal oxide particle in the form of a secondary particle including a primary particle, a coating layer including a boron compound is positioned on at least a portion of a surface of the primary particle, and the boron compound includes an amorphous structure.

A lithium battery positive active material precursor, a preparation method therefor and the use thereof are provided. The precursor has a chemical formula of Ni.sub.xCo.sub.yM.sub.z(OH).sub.2, wherein M is at least one metal selected from the group consisting of Fe, Cr, Cu, Ti, Mg, W, Mo, Nb, Zn, Sn, Zr, Ga, Mn and Al, 0.3≤x≤1, 0<y≤0.5, 0<z≤0.3; and the precursor comprises aggregates of platy monocrystals and polyhedral monocrystal particles. In the XRD pattern of the precursor, I(001), I(100) and I(101) satisfy the following relationship: I(001)/I(100) is not less than about 1.5, and I(001)/I(101) is not less than about 1.2.

The present invention comprises, in lithium composite oxide particles, an overlithiated oxide having a layered crystal structure and represented by chemical formula 1 below, and comprises a lithium manganese oxide represented by chemical formula 2 below outside the lithium composite oxide particles, wherein the overlithiated oxide included in the particles and the lithium manganese oxide included outside the particles have different Li/IM values. [Chemical formula 1] rLi.sub.2MnO.sub.3.(1-r)Li.sub.aNi.sub.xCo.sub.yMn.sub.zM1.sub.1-(x+y+z)O.sub.2 (wherein, 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 any one selected from Na, K, Mg, Al, Fe, Cr, Y, Sn, Ti, B, P, Zr, Ru, Nb, W, Ba, Sr, La, Ga, Mg, Gd, Sin, Ca, Ce, Fe, Al, Ta, Mo, Se, Zn, Nb, Cu, in, S, B, and Bi) [Chemical formula 2] Li.sub.bMn.sub.pO.sub.q (wherein, in chemical formula 2, 0.1≤b/p≤2.5 and 0<q≤15).

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).

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 positive electrode for a rechargeable lithium battery includes a positive active material for a rechargeable lithium battery that includes a first positive active material including a secondary particle including at least two agglomerated primary particles, where at least a portion of the primary particles has a radial arrangement structure, and a second positive active material having a monolith structure, wherein the first and second positive active materials each include a nickel-based positive active material, and an X-ray diffraction (XRD) peak intensity ratio (I(003)/I(104)) of the positive electrode is greater than or equal to about 3. Further embodiments provide a method of manufacturing the positive electrode for rechargeable lithium battery, and a rechargeable lithium battery including the same.

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 method of making an atomic layer nanoribbon that includes forming a double atomic layer ribbon having a first monolayer and a second monolayer on a surface of the first monolayer, wherein the first monolayer and the second monolayer each contains a transition metal dichalcogenide material, oxidizing at least a portion of the first monolayer to provide an oxidized portion, and removing the oxidized portion to provide an atomic layer nanoribbon of the transition metal dichalcogenide material. Also provided are double atomic layer ribbons, double atomic layer nanoribbons, and single atomic layer nanoribbons prepared according to the method.