A positive-electrode active material precursor for lithium-ion secondary battery includes: a metal complex hydroxide particle, that includes nickel (Ni), manganese (Mn), zirconium (Zr), and an additive element M (M). When a linear analysis is performed by EDX on a cross section of the metal complex hydroxide particle along a direction of diameter from a center, a ratio of a maximum zirconium concentration to an average zirconium concentration is 2 or less.

A method of preparing a positive electrode active material precursor for a secondary battery includes preparing a positive electrode active material precursor by a co-precipitation reaction while adding a transition metal-containing solution containing transition metal cations, a basic solution, and an ammonium solution to a batch-type reactor, wherein a molar ratio of ammonium ions contained in the ammonium solution to the transition metal cations contained in the transition metal-containing solution added to the batch-type reactor is 0.5 or less, and a pH in the batch-type reactor is maintained at 11.2 or less.

When a non-aqueous electrolyte secondary battery in which a positive electrode active material comprising a layered lithium-composite oxide is used for a positive electrode is subjected to charge/discharge under a prescribed condition, in a graph showing the relationship between voltage “V” with discharge during 5.sup.th cycle and value dQ/dV from differentiation of battery capacity “Q” with discharge during 5.sup.th cycle by voltage “V”, peak intensity ratio “r” represented by the equation: r=|Ic|/(|Ia|+|Ib|+|Ic|) satisfies 0<r≤0.25, in which |Ia| is absolute value dQ/dV for a peak top within a range of more than 3.9V to 4.4V or less, |Ib| is absolute value dQ/dV for a peak top within a range of more than 3.5V to 3.9V or less, and |Ic| is absolute value dQ/dV for a peak top within a range of 2.0V or more to 3.5V or less.

The present invention relates to a method of preparing a positive electrode active material precursor for a lithium secondary battery in which particle size uniformity and productivity may be improved by using three reactors, a method of preparing a positive electrode active material for a lithium secondary battery by using the above-prepared positive electrode active material precursor for a lithium secondary battery, and a positive electrode for a lithium secondary battery and a lithium secondary battery which include the above-prepared positive electrode active material for a lithium secondary battery.

A method for forming a Group IV transition metal containing film comprises a) exposing a substrate to a vapor of a Group IV transition metal containing film forming composition; b) exposing the substrate to a co-reactant; and c) repeating the steps of a) and b) until a desired thickness of the Group IV transition metal containing film is deposited on the substrate using a vapor deposition process,

A positive electrode material for a secondary battery and a method of making the same is disclosed herein. In some embodiments, a positive electrode active material includes a lithium composite transition metal oxide including nickel (Ni), cobalt (Co), and manganese (Mn), wherein the lithium composite transition metal oxide includes 60 mol % or more of the nickel (Ni) among metals excluding lithium, and a coating layer is formed on surfaces of particles of the lithium composite transition metal oxide, wherein the coating layer includes a lithium-polymer compound which is formed by a reaction of a lithium by-product with a polymer.

A positive electrode active material and a preparation method thereof, a positive electrode plate, a lithium-ion secondary battery, and a battery module, battery pack, and apparatus containing such lithium-ion secondary battery are provided. The positive electrode active material includes matrix particles and a coating layer covering an exterior surface of the matrix particle, where the matrix particle includes a lithium nickel cobalt manganese oxide, and the coating layer includes an oxide of element M.sup.1; the matrix particle is doped with element M.sup.2 and element M.sup.3, element M.sup.2 in the matrix particle is uniformly distributed, and element M.sup.3 in the matrix particle has a decreasing concentration from the exterior surface to a core of the matrix particle; and element M.sup.1 and element M.sup.3 are each independently selected from one or more of Mg, Al, Ca, Ba, Ti, Zr, Zn, and B, and element M.sup.2 includes one or more of Si, Ti, Cr, Mo, V, Ge, Se, Zr, Nb, Ru, Rh, Pd, Sb, Te, Ce, and W.

The present application discloses a positive electrode active material including a lithium nickel cobalt manganese oxide, the molar content of nickel in the lithium nickel cobalt manganese oxide accounts for 60%-90% of the total molar content of nickel, cobalt and manganese, and the lithium nickel cobalt manganese oxide has a layered crystal structure of a space group R3m; a transition metal layer of the lithium nickel cobalt manganese oxide includes a doping element, and the local mass concentration of the doping element in particles of the positive electrode active material has a relative deviation of 20% or less; and in a differential scanning calorimetry spectrum of the positive electrode active material in a 78% delithiation state, an initial exothermic temperature of a main exothermic peak is 200° C. or more, and an integral area of the main exothermic peak is 100 J/g or less.

A positive electrode active material for a lithium ion secondary battery, in which a lithium-nickel-manganese composite oxide has a hexagonal layered structure, a mole number ratio of metal elements is represented as Li:Ni:Mn:M:Ti=a:(1−x−y−z):x:y:z, provided that 0.97≤a≤1.25, 0.05≤x≤0.15, 0≤y≤0.15, and 0.01≤z≤0.05, a ratio of a total amount of peak intensities of most intense lines of a titanium compound to a (003) diffraction peak intensity in XRD measurement is 0.2 or less, and a volume resistivity as determined by powder compact resistivity measurement compressed to 4.0 g/cm.sup.3 is 1.0×10.sup.2 Ω.Math.cm or more and 1.0×10.sup.4 Ω.Math.cm or less.

A positive electrode active material for a lithium ion secondary battery, in which a lithium-nickel-manganese composite oxide has a hexagonal layered structure, a mole number ratio of metal elements is represented as Li:Ni:Mn:M:Ti=a:(1-x-y-z):x:y:z, provided that 0.97≤a≤1.25, 0.05≤x≤0.15, 0≤y≤0.15, and 0.01≤z≤0.05, a ratio of a total amount of peak intensities of most intense lines of a titanium compound to a (003) diffraction peak intensity in XRD measurement is 0.2 or less, a crystallite diameter at (003) plane is 160 nm to 300 nm, and an amount of lithium to be eluted in water when the positive electrode active material is immersed in water is 0.07% by mass or less.