Abstract: According to one embodiment, a positive electrode active material for a non-aqueous electrolyte secondary battery contains a lithium/transition metal composite oxide that contains 80 mol % or more, relative to the total mol number of metal elements other than Li, of Ni and at least one kind of metal element selected from among Co, Mn, Al, W, Mg, Mo, Nb, Ti, Si and Zr. When a filtrate of a suspension, said suspension being prepared by adding 250 mg of the positive electrode active material to 10 mL of a 17.5 mass % aqueous solution of hydrochloric acid, dissolving by heating at 90° C. for 2 hours and then diluting to 50 mL, is analyzed by inductively coupled plasma mass spectrometry, the elution amount of S in the filtrate is 0.002 mmol or greater.

Abstract: A positive electrode active material for nonaqueous electrolyte secondary batteries according to one embodiment of the present invention contains: a first lithium transition metal composite oxide that is represented by general formula LixNi1-y-zCoyMzO2 (wherein 0.8?x?1.2, 0?y?0.2, 0<z?0.5, and M represents at least one metal element excluding Li, Ni and Co); and a second lithium transition metal composite oxide that has at least one diffraction peak which has a peak top at a diffraction angle (2?) of from 21.40° to 21.65° in radiation X-ray diffraction (with a light energy of 16 keV).

Abstract: The positive electrode mixture layer of this nonaqueous electrolyte secondary battery positive electrode, which is one exemplary embodiment, contains a first lithium-transition-metal composite oxide represented by general formula LixNi1?y?zCoyMzO2 (in the formula. 0.8?x?1.2, 0?y?0.2, 0<z?0.5, and M is at least one metal element excluding Li, Ni, and Co), a second lithium-transition-metal composite oxide represented by general formula LiaNi2?a?bMebO2 (in the formula, 0<a?0.5, 0?b?0.5, and Me is at least one metal element excluding Li and Ni), and a carbon nanotube.

Abstract: This non-aqueous electrolyte secondary battery, which is one example of an embodiment, comprises: a positive electrode that has a positive electrode mixture layer; a negative electrode; a separator that is interposed between the positive electrode and the negative electrode; and a non-aqueous electrolyte. The positive electrode mixture layer contains a first lithium-and-transition-metal composite oxide represented by general formula LixNi1?y?zCoyMzO2 (in the formula, 0.8?x?1.2, 0?y?0.2, 0<z?0.5, and M is at least one metal element excluding Li, Ni, and Co), and a second lithium-and-transition-metal composite oxide represented by general formula LiaNi2?a?bMebO2 (in the formula, 0<a?0.5, 0?b?0.5, and Me is at least one metal element excluding Li and Ni). The separator has: a base material; and a surface layer that includes inorganic particles and a binder, and is formed on the surface of the base material facing toward the positive electrode.

Abstract: This non-aqueous electrolyte secondary battery, which is one example of an embodiment, comprises: a positive electrode that has a positive electrode mixture layer; a negative electrode; and a non-aqueous electrolyte. The positive electrode mixture layer contains a first lithium-and-transition-metal composite oxide represented by general formula LixNi1-y-zCoyMzO2 (in the formula, 0.8?x?1.2, 0?y?0.2, 0<z?0.5, and M is at least one metal element excluding Li, Ni, and Co), and a second lithium-and-transition-metal composite oxide represented by general formula LiaNi2-a-bMebO2 (in the formula, 0<a?0.5, 0?b?0.5, and Me is at least one metal element excluding Li and Ni). The non-aqueous electrolyte contains a sulfonyl imide salt.

Abstract: A positive electrode active material for a non-aqueous electrolyte secondary battery according to one exemplary embodiment comprises: a first lithium transition metal composite oxide represented by general formula LiaNibM11-bO2 (in the formula, 1.5?a?2.5, 0.95?b?1.00, and M1 is at least one metal element excluding Li and Ni); and a second lithium transition metal composite oxide represented by general formula LicNi2-c-dM2dO2 (in the formula, 0<c?0.5, 0?d?0.5, and M2 is at least one metal element excluding Li and Ni).

Abstract: A positive electrode active material according to the present invention contains first and second lithium-transition metal complex oxides at respective predetermined proportions. The first lithium-transition metal complex oxide includes a core containing at least Li, Ni, and M1 (M1 is at least one element selected from the group consisting of Mn, W, Mg, Mo, Nb, Ti, Si, and Al), and a surface modification layer that is present at least on the surface of the core. The surface modification layer includes M2 (M2 is at least one element selected from the group consisting of Sr, Ca, W, Mg, Nb, and Al). The second lithium-transition metal complex oxide includes at least a compound represented by general formula LiaNibM31-bO2 (in the formula. 1.5?a?2.5 and 0.95?b?1 are satisfied, and M3 is at least one element selected from the group consisting of Cu, Sr, Ca, Nb, Si, and Al).

Abstract: This positive electrode active material for nonaqueous electrolyte secondary batteries contains a lithium transition metal composite oxide which contains 80% by mole or more of Ni relative to the total number of moles of the metal elements excluding Li, and at least one of Mn and Al, wherein: the total amount of Mn and Al is 5% by mole or more relative to the total number of moles of the metal elements excluding Li; and with respect to a filtrate of a suspension, which has been prepared by adding 250 mg of the positive electrode active material to 10 mL of a 17.5 mass% aqueous solution of hydrochloric acid, dissolving the positive electrode active material therein by 2-hour heating at 90° C., and subsequently diluting the solution to 50 mL, the elution amount of S in the filtrate as determined by inductively coupled plasma mass spectrometry is 0.002 mmol or more.

Abstract: According to one embodiment, a positive electrode active material for a non-aqueous electrolyte secondary battery contains a lithium/transition metal composite oxide that contains 80 mol % or more, relative to the total mol number of metal elements other than Li, of Ni and at least one kind of metal element selected from among Co, Mn, Al, W, Mg, Mo, Nb, Ti, Si and Zr. When a filtrate of a suspension, said suspension being prepared by adding 250 mg of the positive electrode active material to 10 mL of a 17.5 mass % aqueous solution of hydrochloric acid, dissolving by heating at 90° C. for 2 hours and then diluting to 50 mL, is analyzed by inductively coupled plasma mass spectrometry, the elution amount of S in the filtrate is 0.002 mmol or greater.

Abstract: A nonaqueous electrolyte secondary battery includes: a positive electrode containing a positive electrode active material; a negative electrode containing a negative electrode active material; and a nonaqueous electrolyte. The positive electrode active material includes a complex oxide containing lithium and metal M excluding lithium, where a plurality of primary particles of the complex oxide are aggregated to form a secondary particle. The metal M includes at least nickel and aluminum and/or manganese, where an atomic ratio of nickel to the metal M (Ni/M) is 0.8 or more and less than 1.0. The primary particles have an average particle size of 0.20 ?m or more and 0.35 ?m or less.