Abstract: A positive electrode active material for lithium secondary batteries which is able to doped/undoped with lithium ions and contains at least Ni, in which a ratio P/Q (atom %/mass %) of a concentration P (atom %) of sulfur atoms being present in a surface of the positive electrode active material to a concentration Q (mass %) of sulfuric acid radicals being present in the whole positive electrode active material is more than 0.8 and less than 5.0, and the Q (mass %) is 0.01 or more and 2.0 or less.

Abstract: The present invention provides a positive electrode active material for lithium secondary batteries including: secondary particles obtained by aggregating primary particles capable of being doped and de-doped with lithium ions, in which the secondary particles have pores, and pore distribution obtained by a mercury intrusion method satisfies requirements (1) and (2) below: (1) pores that are present in any one or both of the secondary particles or spaces between the secondary particles have a pore peak within a range of a pore radius of equal to or greater than 10 nm and equal to or less than 200 nm; and (2) a total surface area of pores that have pore radii of equal to or greater than 100 nm and equal to or less than 10 ?m among the pores that are present in any one or both of the secondary particles or spaces between the secondary particles is less than 1.1 m2/g.

Abstract: The object of the present invention is to provide a positive electrode active material usable for a lithium ion battery capable of high charge/discharge cycle performance and high discharge capacity. The positive electrode active material for a lithium secondary battery has a layered structure and comprises at least nickel, cobalt and manganese. Further, the positive electrode active material satisfies requirements (1) to (3) below: (1) a primary particle size of 0.1 ?m to 1 ?m, and a 50% cumulative particle size D50 of 1 ?m to 10 ?m, (2) a ratio (D90/D10) of volume-based 90% cumulative particle size D50 to volume-based 10% cumulative particle size D10 of 2 to 6, and (3) a lithium carbonate content in a residual alkali on particle surfaces of 0.1% by mass to 0.8% by mass as measured by neutralization titration.

Abstract: A positive electrode active material for a lithium secondary battery contains an active material powder including secondary particles that are aggregates of primary particles into and from which lithium ions are doped and dedoped, includes the secondary particles having voids therein, and satisfies the following Requirements (1) and (2) in pore distribution of the positive electrode active material for a lithium secondary battery measured by a mercury porosimetry method. (1) A positive electrode active material for a lithium secondary battery has a pore peak in a range in which a pore radius is 10 nm or more and 200 nm or less. (2) A positive electrode active material for a lithium secondary battery has three or more inflection points of a cumulative pore volume in a range in which the pore radius is 10 nm or more and 3000 nm or less.

Abstract: A positive electrode active material, which has a crystallite size ?/crystallite size ? ratio (?/?) of 1 to 1.75 or less, wherein the crystallite size ? is within a peak region of 2?=18.7±1° and the crystallite size ? is within a peak region of 2?=44.6±1°, each determined by a powder X-ray diffraction measurement using Cu-K? ray, and has a composition represented by formula (I) below: Li[Lix(NiaCobMncMd)1-x]O2??(I) wherein 0?x?0.2, 0.3<a<0.7, 0<b<0.4, 0<c<0.4, 0?d<0.1, a+b+c+d=1, and M is at least one metal selected from the group consisting of Fe, Cr, Ti, Mg, Al and Zr.

Abstract: The present invention provides a positive electrode active material for lithium secondary batteries including: secondary particles obtained by aggregating primary particles capable of being doped and de-doped with lithium ions, in which the secondary particles have pores, and pore distribution obtained by a mercury intrusion method satisfies requirements (1) and (2) below: (1) pores that are present in any one or both of the secondary particles or spaces between the secondary particles have a pore peak within a range of a pore radius of equal to or greater than 10 nm and equal to or less than 200 nm; and (2) a total surface area of pores that have pore radii of equal to or greater than 100 nm and equal to or less than 10 ?m among the pores that are present in any one or both of the secondary particles or spaces between the secondary particles is less than 1.1 m2/g.

Abstract: The present invention provides a lithium secondary battery positive electrode, wherein an electrode mixture layer that includes a positive electrode active material for a lithium secondary battery including secondary particles obtained by aggregating primary particles capable of being doped or de-doped with lithium ions being aggregated, a conductive material, and a binding agent and a current collector are laminated, and requirements (1) and (2) below are satisfied: (1) 180-degree peeling strength between the current collector and the electrode mixture layer is equal to or greater than 140 N/m; and (2) a BET specific surface area of the electrode mixture layer is equal to or greater than 4.0 m2/g and equal to or less than 8.5 m2/g.

Abstract: A positive electrode active material for lithium secondary batteries which is able to doped/undoped with lithium ions and contains at least Ni, in which a ratio P/Q (atom %/mass %) of a concentration P (atom %) of sulfur atoms being present in a surface of the positive electrode active material to a concentration Q (mass %) of sulfuric acid radicals being present in the whole positive electrode active material is more than 0.8 and less than 5.0, and the Q (mass %) is 0.01 or more and 2.0 or less.

Abstract: A positive electrode active material, which has a crystallite size ?/crystallite size ? ratio (?/?) of 1 to 1.75 or less, wherein the crystallite size ? is within a peak region of 2?=18.7±1° and the crystallite size ? is within a peak region of 2?=44.6±1°, each determined by a powder X-ray diffraction measurement using Cu-K? ray, and has a composition represented by formula (I) below: Li[Lix(NiaCobMncMd)1-x]O2??(I) wherein 0?x?0.2, 0.3<a<0.7, 0<b<0.4, 0<c<0.4, 0?d<0.1, a+b+c+d=1, and M is at least one metal selected from the group consisting of Fe, Cr, Ti, Mg, Al and Zr.

Abstract: The object of the present invention is to provide a positive electrode active material usable for a lithium ion battery capable of high charge/discharge cycle performance and high discharge capacity. The positive electrode active material for a lithium secondary battery has a layered structure and comprises at least nickel, cobalt and manganese. Further, the positive electrode active material satisfies requirements (1) to (3) below: (1) a primary particle size of 0.1 ?m to 1 ?m, and a 50% cumulative particle size D50 of 1 ?m to 10 ?m, (2) a ratio (D90/D10) of volume-based 90% cumulative particle size D50 to volume-based 10% cumulative particle size D10 of 2 to 6, and (3) a lithium carbonate content in a residual alkali on particle surfaces of 0.1% by mass to 0.8% by mass as measured by neutralization titration.