Abstract: A positive electrode active material includes positive electrode active material particles including a composite oxide with a hexagonal crystal structure. The composite oxide includes Li, Co, and at least one element M1 selected from the group consisting of Ni, Fe, Pb, Mg, Al, K, Na, Ca, Si, Ti, Sn, V, Ge, Ga, B, As, Zr, Mn and Cr, and the at least one element M1 is provided on a surface of the positive electrode active material particles. An atomic ratio of a total amount of the at least one element M1 to an amount of Co on the surface of the positive electrode active material particles is from 0.6 to 1.3.

Abstract: A secondary battery includes a positive electrode including a positive electrode active material, a negative electrode, and an electrolytic solution. The positive electrode active material includes a lithium composite oxide of a layered rock-salt type. The lithium composite oxide includes lithium, cobalt, aluminum, magnesium, an additional element, and oxygen as constituent elements. The additional element includes at least one of fluorine, phosphorous, or sulfur. According to an analysis of the positive electrode active material by inductively coupled plasma optical emission spectrometry, a content of aluminum is greater than a content of magnesium.

Abstract: A positive electrode active material includes powder of composite particles including a lithium transition metal composite oxide having a lamellar rock-salt structure and a spinel phase. The spinel phase includes an oxide including lithium and at least a first element X1 selected from the group consisting of magnesium, aluminum, titanium, manganese, yttrium, zirconium, molybdenum, and tungsten, and the lithium transition metal composite oxide includes nickel or cobalt and the first element X1.

Abstract: Provided is a nonaqueous electrolyte secondary battery including a positive electrode, a negative electrode, and an electrolyte. The positive electrode includes positive active material particles having a layered rock salt type crystal structure. A filling ratio of the positive active material particles in the positive electrode is 85% or more. The positive active material particles include broken particles in which a longest diameter is within a range from 15 ?m to 30 ?m. A crack with a length ? times or more and ? times or less the longest diameter of the broken particles is present. The crack has an intersection, and an abundance ratio x of broken particle is 20% or less.

Abstract: A positive electrode active material includes positive electrode active material particles including a composite oxide with a hexagonal crystal structure. The composite oxide includes Li, Co, and at least one element M1 selected from the group consisting of Ni, Fe, Pb, Mg, Al, K, Na, Ca, Si, Ti, Sn, V, Ge, Ga, B, As, Zr, Mn and Cr, and the at least one element M1 is provided on a surface of the positive electrode active material particles. An atomic ratio of a total amount of the at least one element M1 to an amount of Co on the surface of the positive electrode active material particles is from 0.6 to 1.3.

Abstract: A positive electrode active material includes powder of composite particles including a lithium transition metal composite oxide having a lamellar rock-salt structure and a spinel phase. The spinel phase includes an oxide including lithium and at least a first element X1 selected from the group consisting of magnesium, aluminum, titanium, manganese, yttrium, zirconium, molybdenum, and tungsten, and the lithium transition metal composite oxide includes nickel or cobalt and the first element X1.

Abstract: A positive electrode active material includes secondary particles obtained by aggregation of a plurality of primary particles. The primary particles include, core particles including a lithium composite oxide, and a layer that is provided on surfaces of the core particles and includes a lithium composite oxide. The lithium composite oxide included in the core particles and the lithium composite oxide included in the layer have the same composition or almost the same composition, and crystallinity of the lithium composite oxide included in the layer is lower than crystallinity of the lithium composite oxide included in the core particles.

Abstract: A positive electrode active material includes: a composite particle that includes a particle containing a lithium transition metal composite oxide of Li and Co and a layer that is provided on a surface of the particle and includes an oxide of Li, Ni and Mn. Ni and Mn have a concentration distribution centered on the center from a surface of the composite particle, in a depth range in which a ratio d (%) satisfies 0.04%?d?0.20%, a mole fraction rn of Ni and a mole fraction rm of Mn are within ranges of 0.05?rn and 0.05?rm, respectively, and a ratio rn2/rn1 and a ratio rm2/rm1 are within ranges of 0.85?rn2/rn1?1.0 and 0.85?rm2/rm1?1.0, respectively.

Abstract: A positive electrode active material includes: a particle including a lithium composite oxide; a first layer that is provided on a surface of the particle and includes a lithium composite oxide; and a second layer that is provided on a surface of the first layer. The lithium composite oxide included in the particle and the lithium composite oxide included in the first layer have the same composition or almost the same composition, the second layer includes an oxide or a fluoride, and the lithium composite oxide included in the first layer has lower crystallinity than the lithium composite oxide included in the particle.

Abstract: A secondary battery includes a positive electrode including a positive electrode active material which includes a center portion including a lithium composite oxide including cobalt and an element M, and a covering portion that is provided on at least a portion of a surface of the center portion and contains lithium, nickel, and manganese elements. A concentration thereof has a gradient in a direction from a surface toward a center of the positive electrode active material. A first molar fraction satisfies 0.03<R<0.13 at a first position within the covering portion where the proportion D satisfies D=0.05. A second molar fraction satisfies 0.01<R<0.13 at a second position within the center portion where the proportion D satisfies D=0.3. A ratio F of the second molar fraction to the first molar fraction satisfies 0.7?F?1.

Abstract: A positive electrode active material includes particles composed of a compound oxide; and coating layers composed of a compound oxide formed on at least parts of the surfaces of the particles. The particles have a layered structure and include a first compound oxide mainly composed of lithium and nickel. The coating layers include a second compound oxide mainly composed of lithium and titanium. The ratio by weight of the first compound oxide to the second compound oxide is between 96:4 and 65:35. The positive electrode active material has a mean particle diameter of 5 to 20 ?m.

Abstract: A secondary battery includes a positive electrode including a positive electrode active material which includes a center portion including a lithium composite oxide including cobalt and an element M, and a covering portion that is provided on at least a portion of a surface of the center portion and contains lithium, nickel, and manganese elements. A concentration thereof has a gradient in a direction from a surface toward a center of the positive electrode active material. A first molar fraction satisfies 0.03<R<0.13 at a first position within the covering portion where the proportion D satisfies D=0.05. A second molar fraction satisfies 0.01<R<0.13 at a second position within the center portion where the proportion D satisfies D=0.3. A ratio F of the second molar fraction to the first molar fraction satisfies 0.7?F?1.

Abstract: A battery capable of improving the energy density and improving the battery characteristics such as cycle characteristics and high temperature storage characteristics. A cathode and an anode are oppositely arranged with a separator in between. The open circuit voltage in full charge is in the range from 4.25 V to 6.00 V. The separator has a base material layer and a surface layer. The surface layer opposed to the cathode is formed from at least one from the group consisting of polyvinylidene fluoride, polytetrafluoroethylene, polypropylene, and aramid.

Abstract: A lithium ion secondary battery includes a positive electrode, a negative electrode, and an electrolytic solution. The positive electrode contains a lithium composite oxide. The negative electrode contains a material including at least one of silicon Si and tin Sn as a constituent element. The lithium composite oxide includes lithium Li having a composition ratio a, a first element having a composition ratio b, and a second element having a composition ratio c as a constituent element. The first element including two kinds or more selected from among manganese Mn, nickel Ni, and cobalt Co, and including at least manganese. The second element including at least one kind selected from among aluminum Al, titanium Ti, magnesium Mg, and boron B. The composition ratios a to c satisfy the relationships of 1.1<a<1.3, 0.7<b+c<1.1, 0<c<0.1, and a>b+c.

Abstract: A cathode active material having a large capacity and improved charge/discharge cycle characteristics is disclosed. A battery has a cathode (2) having a cathode active material, an anode (3) and a non-aqueous electrolyte, and uses a cathode active material composed of a mixture of a first lithium-transition metal composite oxide containing Ni and Co and comprising a layer structure and a second lithium-transition metal composite oxide containing Ni and Mn and comprising a layer structure.

Abstract: A secondary battery includes: a cathode including an active material; an anode; and an electrolytic solution, and the active material includes a plurality of active material particles as primary particles and a carbon material. The active material particles contain a polyanion-based compound. The carbon material contains a first carbon material present on surfaces of the active material particles, and a second carbon material present between the active material particles provided with the first carbon material. A ratio B/A between a total carbon amount A and a surface carbon amount B of the active material satisfies 7<B/A<11.5. A ratio D/C between a specific surface area C of the active material, and an oil feed amount D of N-methyl-2-pyrrolidone satisfies 1.5<D/C?2.

Abstract: A battery is composed of a positive electrode in which a positive electrode active material layer including a positive electrode active material is formed on a positive electrode collector, a negative electrode in which a negative electrode active material layer including a negative electrode active material is formed on a negative electrode collector, a separator provided between the positive electrode and the negative electrode, and an electrolyte impregnated in the separator. The battery further includes at least one of a heteropoly acid and a heteropoly acid compound as an additive at least in one of the positive electrode, the negative electrode, the separator, and the electrolyte.

Abstract: A lithium secondary battery includes a positive electrode, a negative electrode, and an electrolyte solution. The positive electrode contains a positive electrode active material including element M2 incorporated in a crystal structure in a surface layer area of a complex oxide, the oxide including the element M1 and being represented by the following formula (1), M2 being different from M1. The element M2 is at least one kind selected from the group consisting of magnesium Mg, calcium Ca, titanium Ti, zirconium Zr, sulfur S, fluorine F, iron Fe, copper Cu, boron B, aluminum Al, phosphorus P, carbon C, manganese Mn, nickel Ni, and cobalt Co. Li1+a(MnbCocNi1?b?c)1?aM1dO2?e??(1) M1 is at least one kind of aluminum, magnesium, zirconium, titanium, barium Ba, boron, silicon Si, and iron, a satisfies 0<a<0.25, b satisfies 0.5?b<0.7, c satisfies 0?c<1?b, d satisfies 0.01?d?0.2, and e satisfies 0?e?1.

Abstract: A positive electrode active material includes: a particle including a lithium composite oxide; a first layer that is provided on a surface of the particle and includes a lithium composite oxide; and a second layer that is provided on a surface of the first layer. The lithium composite oxide included in the particle and the lithium composite oxide included in the first layer have the same composition or almost the same composition, the second layer includes an oxide or a fluoride, and the lithium composite oxide included in the first layer has lower crystallinity than the lithium composite oxide included in the particle.

Abstract: A positive electrode active material includes: secondary particles obtained by aggregation of a plurality of primary particles. The primary particles include, core particles including a lithium composite oxide, and a layer that is provided on surfaces of the core particles and includes a lithium composite oxide. The lithium composite oxide included in the core particles and the lithium composite oxide included in the layer have the same composition or almost the same composition, and crystallinity of the lithium composite oxide included in the layer is lower than crystallinity of the lithium composite oxide included in the core particles.