Abstract: Provided is a cathode active material having a composition represented by the following Formula I: LiFe(P1-XO4) (I) wherein a molar fraction (1?x) of phosphorus (P) is in the range of 0.910 to 0.999, to allow operational efficiency of the cathode active material to be leveled to a lower operational efficiency of an anode active material and improve energy density of the cathode active material. Furthermore, a cathode active material, wherein a molar fraction (1?x) of phosphorus (P) is lower than 1, contains both Fe2+ and Fe3+, thus advantageously preventing structural deformation, improving ionic conductivity, exhibiting superior rate properties and inhibiting IR drop upon charge/discharge, thereby imparting high energy density to batteries.

Abstract: Provided is a lithium transition metal oxide having an ?-NaFeO2 layered crystal structure, as a cathode active material for lithium secondary battery, wherein the transition metal includes a blend of Ni and Mn, an average oxidation number of the transition metals except lithium is +3 or higher, and the lithium transition metal oxide satisfies Equations 1 and 2: 1.0<m(Ni)/m(Mn)??(1) m(Ni2+)/m(Mn4+)<1??(2) wherein m(Ni)/m(Mn) represents a molar ratio of nickel to manganese and m (Ni2+)/m (Mn4+) represents a molar ratio of Ni2+ to Mn4+. The cathode active material of the present invention has a uniform and stable layered structure through control of oxidation number of transition metals to a level higher than +3, in contrast to conventional cathode active materials, thus advantageously exerting improved overall electrochemical properties including electric capacity, in particular, superior high-rate charge/discharge characteristics.

Abstract: Disclosed is a cathode active material in which lithium cobalt oxide particles and manganese (Mn) or titanium (Ti)-containing lithium transition metal oxide particles co-exist and a method of preparing the same.

Abstract: Provided is a cathode mix for lithium secondary batteries, comprising a cathode active material having a composition represented by the following Formula I: LiFe(P1-XO4) (I) wherein a molar fraction (1?x) of phosphorus (P) is in the range of 0.910 to 0.999, to allow operational efficiency of the cathode active material to be leveled to a lower operational efficiency of an anode active material and improve energy density of the cathode active material. The cathode mix maximizes operational efficiency of batteries, minimizes electrode waste and thus reduces manufacturing costs of batteries. Furthermore, The cathode active material, wherein a molar fraction (1?x) of phosphorus (P) is lower than 1, according to the present invention contains both Fe2+ and Fe3+, thus advantageously causing no structural deformation, improving ionic conductivity, exhibiting superior rate properties, inhibiting IR drop upon charge/discharge, thereby imparting high energy density to batteries.

Abstract: Provided is a cathode material for a lithium secondary battery, comprising a heat-treated mixture of an oxide powder (a) represented by Formula I and an oxide powder (b) represented by Formula II, wherein a mixing ratio of the oxide powder (a):oxide powder (b) is in a range of 30:70 to 90:10, the oxide powder (a) is monolithic particles having a D50 of more than 10 ?m, and the oxide powder (b) is agglomerated particles having a D50 of less than 10 ?m, and heat treatment is carried out at a temperature of 400° C. or higher. LiCoO2??(I) LizMO2??(II) wherein 0.95<z<1.1; M=Ni1-x-yMnxCoy, 0<y<0.5, and a ratio of Mn to Ni (x/(1?x?y)) is in a range of 0.4 to 1.1.

Abstract: The present invention provides a LiCoO2-containing powder comprising LiCoO2 having a stoichiometric composition via heat treatment of a lithium cobalt oxide and a lithium buffer material to make equilibrium of a lithium chemical potential there between; a lithium buffer material which acts as a Li acceptor or a Li donor to remove or supplement Li-excess or Li-deficiency, coexisting with a stoichiometric lithium metal oxide; and a method for preparing a LiCoO2-containing powder. Further, provided is an electrode comprising the above-mentioned LiCoO2-containing powder as an active material, and a rechargeable battery comprising the same electrode.

Abstract: Disclosed is lithium iron phosphate having an olivine crystal structure wherein carbon (C) is coated on particle surfaces of the lithium iron phosphate, wherein, when a powder of the lithium iron phosphate is dispersed in water, water is removed from the resulting dispersion and the resulting lithium iron phosphate residue is quantitatively analyzed, a ratio of the carbon-released lithium iron phosphate with respect to the total weight of the carbon-coated lithium iron phosphate is 0.005% by weight or less. Advantageously, the olivine-type lithium iron phosphate is not readily separated through uniform thin film coating on the surface of the lithium iron phosphate and exhibits superior conductivity and density, since carbon is coated on particle surfaces of lithium iron phosphate in a state in which the amount of carbon released in water is considerably small.

Abstract: Provided is an electrode active material comprising a nickel-based lithium transition metal oxide (LiMO2) wherein the nickel-based lithium transition metal oxide contains nickel (Ni) and at least one transition metal selected from the group consisting of manganese (Mn) and cobalt (Co), wherein the content of nickel is 50% or higher, based on the total weight of transition metals, and has a layered crystal structure and an average primary diameter of 3 ?m or higher, wherein the amount of Ni2+ taking the lithium site in the layered crystal structure is 5.0 atom % or less.

Abstract: Provided is a method for preparing a lithium mixed transition metal oxide, comprising subjecting Li2CO3 and a mixed transition metal precursor to a solid-state reaction under an oxygen-deficient atmosphere with an oxygen concentration of 10 to 50% to thereby prepare a powdered lithium mixed transition metal oxide having a composition represented by Formula I of LixMyO2 wherein M, x and y are as defined in the specification. Therefore, since the high-Ni lithium mixed transition metal oxide having a given composition can be prepared by a simple solid-state reaction in air, using a raw material that is cheap and easy to handle, the present invention enables industrial-scale production of the lithium mixed transition metal oxide with significantly decreased production costs and high production efficiency.

Abstract: The present invention provides a LiCoO2-containing powder comprising LiCoO2 having a stoichiometric composition via heat treatment of a lithium cobalt oxide and a lithium buffer material to make equilibrium of a lithium chemical potential therebetween; a lithium buffer material which acts as a Li acceptor or a Li donor to remove or supplement Li-excess or Li-deficiency, coexisting with a stoichiometric lithium metal oxide; and a method for preparing a LiCoO2-containing powder. Further, provided is an electrode comprising the above-mentioned LiCoO2-containing powder as an active material, and a rechargeable battery comprising the same electrode. The present invention enables production of a LiCoO2 electrode active material which has improved high-temperature storage properties and high-voltage cycling properties, and is robust in composition fluctuation in the production process.

Abstract: A hollow silicon-based particle including silicon (Si) or silicon oxide (SiOx, 0<x<2) particle including a hollow core part therein, wherein a size of the hollow core part is from 5 nm to 45 ?m, and a novel preparation method thereof are provided. Hollow is formed in the silicon-based particle, and volume expansion to the inward/outward of the silicon-based particle may be induced. Thus, the volume expansion of the silicon-based particle to the outward may be decreased, and the capacity properties and the life characteristics of a lithium secondary battery may be improved. According to the novel preparation method of the hollow silicon-based particle of the present invention, mass production is possible, producing rate is faster when compared to a common chemical vapor deposition (CVD) method or a vapor-liquid-solid (VLS) method, and the preparation method of the present invention is favorable when considering processes and safety.

Abstract: Provided is an electrode active material comprising a nickel-based lithium transition metal oxide (LiMO2) wherein the nickel-based lithium transition metal oxide contains nickel (Ni) and at least one transition metal selected from the group consisting of manganese (Mn) and cobalt (Co), wherein the content of nickel is 50% or higher, based on the total weight of transition metals, and has a layered crystal structure and an average primary diameter of 3 ?m or higher, wherein the amount of Ni2+ taking the lithium site in the layered crystal structure is 5.0 atom % or less.

Abstract: Provided is a cathode for lithium secondary batteries comprising a combination of one or more compounds selected from Formula 1 and one or more compounds selected from Formula 2. The cathode provides a high-power lithium secondary battery composed of a non-aqueous electrolyte which exhibits long lifespan, long-period storage properties and superior stability at ambient temperature and high temperatures.

Abstract: Provided is an electrode active material comprising a nickel-based lithium transition metal oxide (LiMO2) wherein the nickel-based lithium transition metal oxide contains nickel (Ni) and at least one transition metal selected from the group consisting of manganese (Mn) and cobalt (Co), wherein the content of nickel is 50% or higher, based on the total weight of transition metals, and has a layered crystal structure and an average primary diameter of 3 ?m or higher, wherein the amount of Ni2+ taking the lithium site in the layered crystal structure is 5.0 atom % or less.

Abstract: Provided is a cathode active material containing a Ni-based lithium mixed transition metal oxide. More specifically, the cathode active material comprises the lithium mixed transition metal oxide having a composition represented by Formula I of LixMyO2 wherein M, x and y are as defined in the specification, which is prepared by a solid-state reaction of Li2CO3 with a mixed transition metal precursor under an oxygen-deficient atmosphere, and has a Li2CO3 content of less than 0.07% by weight of the cathode active material as determined by pH titration. The cathode active material in accordance with the present invention and substantially free of water-soluble bases such as lithium carbonates and lithium sulfates and therefore has excellent high-temperature and storage stabilities and a stable crystal structure.

Abstract: Provided is a lithium transition metal oxide having an ?-NaFeO2 layered crystal structure, as a cathode active material for lithium secondary battery, wherein the transition metal includes a blend of Ni and Mn, an average oxidation number of the transition metals except lithium is +3 or higher, and the lithium transition metal oxide satisfies Equations 1 and 2: 1.0<m(Ni)/m(Mn) ??(1) m(Ni2+)/m(Mn4+)<1 ??(2) wherein m(Ni)/m(Mn) represents a molar ratio of nickel to manganese and m (Ni2+)/m (Mn4+) represents a molar ratio of Ni2+ to Mn4+. The cathode active material of the present invention has a uniform and stable layered structure through control of oxidation number of transition metals to a level higher than +3, in contrast to conventional cathode active materials, thus advantageously exerting improved overall electrochemical properties including electric capacity, in particular, superior high-rate charge/discharge characteristics.

Abstract: Disclosed herein is a battery system including two or more kinds of cell lines having different charge and discharge characteristics, wherein each cell line includes one or more battery cells connected in series with each other. In the battery system according to the present invention, the battery cells of at least one cell line exhibit a high-rate charge characteristic, whereas the battery cells of at least another cell line exhibit a high-rate discharge characteristic. Consequently, the high-rate charge and discharge characteristics are improved, and the balance between the charge and discharge characteristics is maintained, whereby the battery system according to the present invention is used as a power source having a high power.

Abstract: Disclosed are precursor particles of a lithium composite transition metal oxide for lithium secondary batteries, wherein the precursor particles of a lithium composite transition metal oxide are composite transition metal hydroxide particles including at least two transition metals and having an average diameter of 1 ?m to 8 ?m, wherein the composite transition metal hydroxide particles exhibit monodisperse particle size distribution and have a coefficient of variation of 0.2 to 0.7, and a cathode active material including the same.