Panasonic Holdings Corporation

Toyota Jidosha Kabushiki Kaisha

Sanyo Electric Co., Ltd.

Panasonic Corporation

Sumitomo Metal Mining Company, Ltd.

Sho Tsuruta

Takashi Ko

Natsumi Goto

Fumiharu Niina

Shinya Suzuki

Ryo Hanazaki

Atsushi Fukui

Kazuhiro Hasegawa

Yuu Takanashi

Kohei Kintsu

Masahisa Fujimoto

Katsunori Yanagida

Keiichi Takahashi

Akira Tsujiko

Haruki Kaneda

Yuki Koshika

Motoharu Saito

Atsushi Kawamura

Disclosed is a non-aqueous electrolyte secondary battery positive electrode that includes a positive electrode core and a positive electrode mixture layer disposed on the positive electrode core. The positive electrode mixture layer contains a positive electrode active material and carbon nanotubes. The positive electrode active material contains a lithium transition metal composite oxide (I) that either comprises secondary particles that are aggregates of primary particles having an average particle size of 1 μm or greater, or is substantially composed of single particles, the lithium transition metal composite oxide (I) having a volume-based median diameter of 0.6 μm to 6 μm, and a lithium transition metal composite oxide (II) that comprises secondary particles that are aggregates of primary particles having an average particle size of less than 1 μm, the lithium transition metal composite oxide (II) having a volume-based median diameter of 3 μm to 25 μm.

Non-aqueous electrolyte secondary battery positive electrode and non-aqueous electrolyte secondary battery

This positive electrode active material for nonaqueous electrolyte secondary batteries is a positive electrode active material that comprises a lithium transition metal composite oxide containing at least 80 mol % Ni with reference to the total number of moles of metal elements excluding Li, and that has B present on the particle surface of at least this composite oxide. Assuming that a particle having a particle diameter larger than the 70% volume-based particle diameter (D70) is denoted as a first particle and a particle having a particle diameter smaller than the 30% volume-based particle diameter (D30) is denoted as a second particle, the mole fraction of B, with reference to the total number of moles of metal elements excluding Li, in the first particle is larger than the mole fraction of B, with reference to the total number of moles of metal elements excluding Li, in the second particle.

Positive electrode active material for nonaqueous electrolyte secondary batteries, and nonaqueous electrolyte secondary battery

The positive electrode active material for a lithium ion secondary battery contains a lithium-nickel-manganese composite oxide, in which metal elements constituting the lithium-nickel-manganese composite oxide include lithium, nickel, manganese, cobalt, titanium, niobium, and optionally zirconium, an amount of substance ratio of the elements is represented as Li:Ni:Mn:Co:Zr:Ti:Nb=a:b:c:d:e:f:g (provided that, 0.97≤a≤1.10, 0.80≤b≤0.88, 0.04≤c≤0.12, 0.04≤d≤0.10, 0≤e≤0.004, 0.003<f≤0.030, 0.001<g≤0.006, and b+c+d+e+f+g=1), in the amount of substance ratio, (f+g)≤0.030 and f>g are satisfied.

Positive electrode active material for lithium ion secondary battery and lithium ion secondary battery

A positive electrode active material for nonaqueous electrolyte secondary batteries contains a lithium transition metal composite oxide that contains not less than 80% by mole of Ni relative to the total number of moles of metal elements other than Li; and Ti is present at least in the surfaces of particles of the composite oxide. With respect to this positive electrode active material, if particles having a volume-based particle diameter more than the 70% particle diameter (D70) are taken as first particles and particles having a volume-based particle diameter less than the 30% particle diameter (D30) are taken as second particles, the molar fraction (A2) of Ti relative to the total number of moles of metal elements in the surfaces of the second particles is higher than the molar fraction (A1) of Ti relative to the total number of moles of metal elements in the surfaces of the first particles.

A positive electrode material consists of composite particles. Each of the composite particles includes a base material particle, a film, and a carbon nanotube. The film covers at least a part of a surface of the base material particle. The base material particle includes a positive electrode active material. The film includes a boron oxide. The carbon nanotube includes a first portion and a second portion. The first portion is buried in the film. The second portion is exposed on a surface of the film.

Positive electrode material, non-aqueous electrolyte secondary battery, and method of producing positive electrode material

A positive electrode active material for a non-aqueous electrolyte secondary battery according to a configuration includes a lithium-transition metal composite oxide containing nickel (Ni) in an amount of greater than or equal to 80 mol %, in which boron (B) is present at least on a particle surface of the lithium-transition metal composite oxide. In the lithium-transition metal composite oxide, when particles having a larger particle size than a volume-based 70% particle size (D70) are first particles and particles having a smaller particle size than a volume-based 30% particle size (D30) are second particles, a coverage ratio of B on surfaces of the second particle is larger than a coverage ratio of B on surfaces of the first particle by 5% or greater.

Positive electrode active material for non-aqueous electrolyte secondary battery, and non-aqueous electrolyte secondary battery

A positive electrode active material for a non-aqueous electrolyte secondary battery according to a configuration includes a lithium-transition metal composite oxide containing nickel (Ni) in an amount of greater than or equal to 80 mol %, in which boron (B) is present at least on a particle surface of the lithium-transition metal composite oxide. In the lithium-transition metal composite oxide, when particles having a larger particle size than a volume-based 70% particle size (D70) are first particles and particles having a smaller particle size than a volume-based 30% particle size (D30) are second particles, a coverage ratio of B on surfaces of the first particles is larger than a coverage ratio of B on surfaces of the second particles by 5% or greater.

An advantage is to provide a non-aqueous electrolyte secondary battery with improved heat resistance. A positive electrode active material contains a lithium-transition metal composite oxide containing 80 mol % or more of Ni and 0.1 mol % to 1.5 mol % of B on the basis of the total number of moles of metal elements excluding Li, and B and at least one element (M1) selected from Groups 4 to 6 are present on at least the surfaces of particles of the composite oxide. When particles having a volume-based particle size larger than 70% particle size (D70) are first particles, and particles having a volume-based particle size smaller than 30% particle size (D30) are second particles, the molar fraction of M1 on the basis of the total number of moles of metallic elements excluding Li on the surfaces of the second particles is greater than that of the first particles.

A high-capacity nonaqueous electrolyte secondary battery having good load characteristics is provided. The nonaqueous electrolyte secondary battery includes a positive electrode containing a positive electrode active material, a negative electrode, and a nonaqueous electrolyte. The positive electrode contains the active material composed of a lithium transition metal oxide and a positive electrode additive composed of an oxide that contains Li and at least two elements other than Li and oxygen and has an antifluorite structure. The nonaqueous electrolyte secondary battery obtained is charged until the potential of the positive electrode is 4.0 V or higher and 4.65 V or lower (vs. Li/Li).

Nonaqueous-electrolyte secondary battery and method for manufacturing nonaqueous-electrolyte secondary battery

Provided is a nonaqueous electrolyte secondary battery in which the structural change of a positive electrode active material is suppressed at high voltage and which can achieve high capacity and long life. The nonaqueous electrolyte secondary battery includes a positive electrode containing a positive electrode active material storing and releasing lithium ions, a negative electrode containing a negative electrode active material storing and releasing lithium ions, and a nonaqueous electrolyte. The positive electrode active material is a cobalt composite oxide which has a layered rock salt structure and which includes a lithium layer containing magnesium, magnesium is present in the lithium layer after charge is performed at a potential of 4.53 V or more versus lithium, and 4.5 mole percent to 10 mole percent of a magnesium-containing compound is present on the negative electrode with respect to magnesium in the positive electrode.

Nonaqueous electrolyte secondary battery

A nonaqueous electrolyte secondary battery which can suppress the change in structure of a positive electrode active material at a high voltage is provided. The nonaqueous electrolyte secondary battery has a positive electrode including a positive electrode active material which absorbs and releases lithium ions; a negative electrode including a negative electrode active material which absorbs and releases lithium ions; and a nonaqueous electrolyte. The positive electrode active material has a surface to which a rare earth compound is adhered and includes a lithium cobalt composite oxide containing at least one type selected from the group consisting of Ni, Mn, Ca, Cu, Zn, Sr, Ge, Sn, Si, P, Nb, Mo, S, and W, and charge is performed so that the potential of the positive electrode is 4.53 V or more with reference to lithium.

A method of manufacturing a non-aqueous electrolyte secondary battery by subjecting a sodium-magnesium-containing oxide represented by the general formula NaMgMO, where 0.65&#x2266;c&#x2266;0.75, 0&#x3c;b&#x2266;0.3, 0&#x2266;a&#x2266;03, and M is at least one of manganese and cobalt, to ion-exchange of sodium for lithium by using a molten salt, an aqueous solution, or an organic solvent, to prepare a positive electrode active material.

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Hyogo, Japan

Sho Tsuruta