Abstract: To provide a cathode active material for a lithium ion secondary battery excellent in the cycle characteristics and rate characteristics even when charging is conducted at a high voltage. A cathode active material for a lithium ion secondary battery, which comprises particles (III) having a covering layer comprising a metal oxide (I) containing at least one metal element selected from the group consisting of elements in Groups 3 and 13 of the periodic table and lanthanoid elements, and a compound (II) containing Li and P, on the surface of a lithium-containing composite oxide comprising lithium and a transition metal element, wherein the atomic ratio of said P to said metal element (P/metal element) contained within 5 nm of the surface layer of the particles (III) is from 0.03 to 0.45.

Abstract: To provide a cathode active material for a lithium ion secondary battery excellent in the cycle characteristics and rate characteristics even when charging is conducted at a high voltage. A cathode active material for a lithium ion secondary battery, which comprises particles (III) having a covering layer comprising a metal oxide (I) containing at least one metal element selected from the group consisting of elements in Groups 3 and 13 of the periodic table and lanthanoid elements, and a compound (II) containing Li and P, on the surface of a lithium-containing composite oxide comprising lithium and a transition metal element, wherein the atomic ratio of said P to said metal element (P/metal element) contained within 5 nm of the surface layer of the particles (III) is from 0.03 to 0.45.

Abstract: To provide a cathode active material for a lithium ion secondary battery excellent in the cycle characteristics and rate characteristics even when charging is conducted at a high voltage. A cathode active material for a lithium ion secondary battery, which comprises particles (III) having a covering layer comprising a metal oxide (I) containing at least one metal element selected from the group consisting of elements in Groups 3 and 13 of the periodic table and lanthanoid elements, and a compound (II) containing Li and P, on the surface of a lithium-containing composite oxide comprising lithium and a transition metal element, wherein the atomic ratio of said P to said metal element (P/metal element) contained within 5 nm of the surface layer of the particles (III) is from 0.03 to 0.45.

Abstract: To provide a cathode active material for a lithium ion secondary battery excellent in the cycle characteristics and rate characteristics even when charging is conducted at a high voltage. A cathode active material for a lithium ion secondary battery, which comprises particles (III) having a covering layer comprising a metal oxide (I) containing at least one metal element selected from the group consisting of Al, Y, Ga, In, La, Pr, Nd, Gd, Dy, Er and Yb, and a compound (II) containing Li and at least one non-metal element selected from the group consisting of S and B, on the surface of a lithium-containing composite oxide, wherein the atomic ratio (the non-metal element/the metal element) contained within 5 nm of the surface layer of the particles (III) is within a specific range.

Abstract: To provide a cathode active material having excellent cycle characteristics and a small decrease in the discharge voltage, and a process for its production. A process for producing a cathode active material, which comprises a step of mixing at least one sulfate (A) selected from the group consisting of a sulfate of Ni, a sulfate of Co and a sulfate of Mn with at least one carbonate (B) selected from the group consisting of sodium carbonate and potassium carbonate in an aqueous solution state to obtain a coprecipitated compound, a step of mixing the coprecipitated compound with an aqueous phosphate solution, a step of volatilizing a water content from the mixture of the coprecipitated compound and the aqueous phosphate solution to obtain a precursor compound, and a step of mixing the precursor compound with lithium carbonate and firing the mixture at from 500 to 1000° C.

Abstract: To provide a process for producing a cathode active material for a lithium ion secondary battery which can improve the initial charge and discharge efficiency (initial efficiency) and the cycle retention of a lithium ion secondary battery. A process for producing a cathode active material for a lithium ion secondary battery, which comprises a step (I) of bringing a lithium-containing composite oxide (I) containing Li element and a transition metal element into contact with a washing liquid and then separating it from the washing liquid to obtain a lithium-containing composite oxide (II), a step (II) of bringing the lithium-containing composite oxide (II) into contact with a composition (1) consisting of an aqueous solution containing an anion (A) preferably containing F and a composition (2) consisting of an aqueous solution containing a cation (M) preferably containing Al or Zr, and a step (III) of heating the lithium-containing composite oxide (II) after the step (II), in this order.

Abstract: To provide a cathode active material for a lithium ion secondary battery, and its production process. A lithium-containing composite oxide containing a transition metal element and a composition (1) are contacted to obtain particles (I) having a compound containing a metal element (M) attached, which are mixed with a compound which generates HF by heating, and the mixture is heated to obtain particles (III) having a covering layer (II) containing the metal element (M) and fluorine element formed on the surface of the lithium-containing composite oxide. Composition (1): a composition having a compound containing no Li element and containing at least one metal element (M) selected from Mg, Ca, Sr, Ba, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Pb, Cu, Zn, Al, In, Sn, Sb, Bi, La, Ce, Pr, Nd, Gd, Dy, Er and Yb dissolved or dispersed in a solvent.

Abstract: To provide a process for producing a cathode active material for a lithium ion secondary battery which can improve the initial charge and discharge efficiency (initial efficiency) and the cycle retention of a lithium ion secondary battery. A process for producing a cathode active material for a lithium ion secondary battery, which comprises a step (I) of bringing a lithium-containing composite oxide (I) containing Li element and a transition metal element into contact with a washing liquid and then separating it from the washing liquid to obtain a lithium-containing composite oxide (II), a step (II) of bringing the lithium-containing composite oxide (II) into contact with a composition (1) consisting of an aqueous solution containing an anion (A) preferably containing F and a composition (2) consisting of an aqueous solution containing a cation (M) preferably containing Al or Zr, and a step (III) of heating the lithium-containing composite oxide (II) after the step (II), in this order.

Abstract: To provide a process for producing a cathode active material for a lithium ion secondary battery, a cathode for a lithium ion secondary battery, and a lithium ion secondary battery. A production process which comprises contacting a lithium-containing composite oxide containing Li element and a transition metal element with a composition (1) {an aqueous solution containing cation M having at least one metal element (m)} and a composition (2) {an aqueous solution containing anion N having at least one element (n) selected from the group consisting of S, P, F and B, forming a hardly soluble salt when reacted with the cation M}, wherein the total amount A (mL/100 g) of the composition (1) and the composition (2) contacted per 100 g of the lithium-containing composite oxide is in a ratio of 0.1<A/B<5 based on the oil absorption B (mL/100 g) of the lithium-containing composite oxide.

Abstract: To provide a cathode active material having excellent cycle characteristics and a small decrease in the discharge voltage, and a process for its production. A process for producing a cathode active material, which comprises a step of mixing at least one sulfate (A) selected from the group consisting of a sulfate of Ni, a sulfate of Co and a sulfate of Mn with at least one carbonate (B) selected from the group consisting of sodium carbonate and potassium carbonate in an aqueous solution state to obtain a coprecipitated compound, a step of mixing the coprecipitated compound with an aqueous phosphate solution, a step of volatilizing a water content from the mixture of the coprecipitated compound and the aqueous phosphate solution to obtain a precursor compound, and a step of mixing the precursor compound with lithium carbonate and firing the mixture at from 500 to 1000° C.

Abstract: To provide a cathode active material for a lithium ion secondary battery excellent in the cycle characteristics, even when charging is carried out under a high voltage. A cathode active material for a lithium ion secondary battery, characterized in that Al and at least one member selected from the group consisting of Y, Gd and Er are present on the surface of particles (1) made of a lithium-containing composite oxide containing Li and at least one transition metal element selected from the group consisting of Ni, Co and Mn.

Abstract: To provide a cathode active material for a lithium ion secondary battery excellent in the cycle characteristics and rate characteristics even when charging is conducted at a high voltage. A cathode active material for a lithium ion secondary battery, which comprises particles (III) having a covering layer comprising a metal oxide (I) containing at least one metal element selected from the group consisting of elements in Groups 3 and 13 of the periodic table and lanthanoid elements, and a compound (II) containing Li and P, on the surface of a lithium-containing composite oxide comprising lithium and a transition metal element, wherein the atomic ratio of said P to said metal element (P/metal element) contained within 5 nm of the surface layer of the particles (III) is from 0.03 to 0.45.

Abstract: To provide a cathode active material for a lithium ion secondary battery excellent in the cycle characteristics and rate characteristics even when charging is conducted at a high voltage. A cathode active material for a lithium ion secondary battery, which comprises particles (III) having a covering layer comprising a metal oxide (I) containing at least one metal element selected from the group consisting of Al, Y, Ga, In, La, Pr, Nd, Gd, Dy, Er and Yb, and a compound (II) containing Li and at least one non-metal element selected from the group consisting of S and B, on the surface of a lithium-containing composite oxide, wherein the atomic ratio (the non-metal element/the metal element) contained within 5 nm of the surface layer of the particles (III) is within a specific range.

Abstract: To produce active material particles for a lithium ion secondary battery, which have favorable surface smoothness, with which the cycle characteristics can be improved while an increase in the internal resistance of an active material layer is suppressed, and with which decomposition of the electrolyte can be suppressed even at a high voltage. Active material particles (X) for a lithium ion secondary battery are contacted with a composition containing a compound (a) having a metal element (M) selected from the group consisting of Li, Mg, Ca, Sr, Ba, Pb, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, Zn, Al, In, Sn, Sb, Bi, La, Ce, Pr, Nd, Gd, Dy, Er and Yb and a composition containing a fluoropolymer (b) having repeating units represented by —[CF2—CR1, R2]— (wherein each of R1 and R2 is H, F or —CF3), followed by heating.

Abstract: To provide a process for producing a cathode active material for a lithium ion secondary battery, a cathode for a lithium ion secondary battery, and a lithium ion secondary battery. A production process which comprises contacting a lithium-containing composite oxide containing Li element and a transition metal element with a composition (1) {an aqueous solution containing cation M having at least one metal element (m)} and a composition (2) {an aqueous solution containing anion N having at least one element (n) selected from the group consisting of S, P, F and B, forming a hardly soluble salt when reacted with the cation M}, wherein the total amount A (mL/100 g) of the composition (1) and the composition (2) contacted per 100 g of the lithium-containing composite oxide is in a ratio of 0.1<A/B<5 based on the oil absorption B (mL/100 g) of the lithium-containing composite oxide.

Abstract: To provide a cathode active material for a lithium ion secondary battery, and its production process. A lithium-containing composite oxide containing a transition metal element and a composition (1) are contacted to obtain particles (I) having a compound containing a metal element (M) attached, which are mixed with a compound which generates HF by heating, and the mixture is heated to obtain particles (III) having a covering layer (II) containing the metal element (M) and fluorine element formed on the surface of the lithium-containing composite oxide. Composition (1): a composition having a compound containing no Li element and containing at least one metal element (M) selected from Mg, Ca, Sr, Ba, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Pb, Cu, Zn, Al, In, Sn, Sb, Bi, La, Ce, Pr, Nd, Gd, Dy, Er and Yb dissolved or dispersed in a solvent.

Abstract: The present invention provides a method for producing a cathode active material for a lithium ion secondary battery excellent in the discharge capacity and the cycle characteristics and having high durability, and methods for producing a lithium ion secondary battery and a cathode for a lithium ion secondary battery. A lithium-containing composite oxide comprising Li element and at least one transition metal element selected from the group consisting of Ni, Co and Mn (provided that the molar amount of the Li element is more than 1.2 times the total molar amount of said transition metal element) and a composition (1) {a composition having a compound (1) containing no Li element and comprising Mn element as an essential component, dissolved or dispersed in a solvent} are contacted, followed by heating to produce a cathode active material for a lithium ion secondary battery.

Abstract: The present invention provides a cathode active material for a lithium ion secondary battery excellent in the cycle characteristics and rate characteristics even when charged at a high voltage, a cathode, a lithium ion secondary battery and a method for producing a cathode active material for a lithium ion secondary battery. The cathode active material comprises particles (II) having an oxide (I) of at least one metal element selected from Zr, Ti and Al locally distributed at the surface of a lithium-containing composite oxide comprising Li element and at least one transition metal element selected from the group consisting of Ni, Co and Mn (provided that the molar amount of the Li element is more than 1.2 times the total molar amount of said transition metal element).

Abstract: To provide a photocurable composition from which a cured product excellent in mold release characteristics and mechanical strength can be obtained, and a method for producing a molded product excellent in durability, with a fine pattern having a reverse pattern of a mold precisely transferred on its surface. A photocurable composition 20 comprising from 15 to 60 mass % of a compound (A) which is an aromatic compound having at least two rings or an alicyclic compound having at least two rings and which has two (meth)acryloyloxy groups, from 5 to 40 mass % of a compound (B) having a fluorine atom and having at least one carbon-carbon unsaturated double bond (excluding the compound (A)), from 10 to 55 mass % of a compound (C) having one (meth)acryloyloxy group (excluding the compound (B)) and from 1 to 12 mass % of a photopolymerization initiator (D) (provided that (A)+(B)+(C)+(D)=100 mass %) is used.

Abstract: To provide a photocurable composition from which a cured product excellent in mold release characteristics and mechanical strength can be obtained, and a method for producing a molded product excellent in durability, with a fine pattern having a reverse pattern of a mold precisely transferred on its surface. A photocurable composition 20 comprising from 15 to 60 mass % of a compound (A) which is an aromatic compound having at least two rings or an alicyclic compound having at least two rings and which has two (meth)acryloyloxy groups, from 5 to 40 mass % of a compound (B) having a fluorine atom and having at least one carbon-carbon unsaturated double bond (excluding the compound (A)), from 10 to 55 mass % of a compound (C) having one (meth)acryloyloxy group (excluding the compound (B)) and from 1 to 12 mass % of a photopolymerization initiator (D) (provided that (A)+(B)+(C)+(D)=100 mass %) is used.