Hitachi Metals, Ltd.

Hitachi, Ltd.

Proterial, Ltd.

Shin-kobe Electric Machinery Co., Ltd.

Genei Nakajima

Hisato Tokoro

Akira Gunji

Tatsuya Toyama

Shuichi Takano

Shin Takahashi

Toyotaka Yuasa

Masahiro Kasai

Akihiko Noie

Akio Takeuchi

The present invention is to provide a cathode active material used for a lithium ion secondary battery which has a large charge-discharge capacity, and excels in charge-discharge cycle properties, output properties and productivity, and, a lithium ion secondary battery using the same. The cathode active material used for a lithium ion secondary battery comprises a lithium transition metal composite oxide represented by the following Formula (1); LiNiCoMnMO, where, in the formula (1), M is at least one metal element other than Li, Ni, Co, and Mn; and a, b, c, d, e, and α satisfy the following conditions: −0.04≤a≤0.04, 0.80≤b<1.00, 0≤c≤0.04, 0<d<0.20, b+c+d+e=1, −0.2<α<0.2, and c and d in the Formula (1) satisfy c/d≤0.75.

Cathode active material used for lithium ion secondary battery and lithium ion secondary battery

A method for manufacturing a cathode active material for a lithium ion secondary battery comprises mixing lithium carbonate and a compound containing a metal element other than Li, and a firing step. The firing step includes at last two stages of controlling firing to different temperatures. The at least two stages include controlling a firing temperature to a lower temperature and controlling a firing temperature to a higher temperature. The firing is controlled is such that the former stage has a lower oxygen concentration in an atmosphere than the latter stage. The firing apparatus comprises at least two firing furnaces of controlling firing temperatures to different temperatures. The at least two firing furnaces include controlling a firing temperature to a lower temperature and controlling firing temperature to a higher temperature. The latter firing furnace has a gas outlet being in communication with the former firing furnace.

Method and firing apparatus for manufacturing cathode active material for lithium ion secondary battery

Provided is a cathode active material for a lithium ion secondary battery in which the secondary particles constituting the powder have a high breaking strength and a good coatability, and a method for manufacturing same. The cathode active material for a lithium ion secondary battery includes a primary particle of a lithium composite compound; and secondary particles formed by an aggregation of primary particles, wherein a ratio between an average particle size of the primary particles and an average particle size of the secondary particles is 0.006 or more and 0.25 or less, an amount of lithium carbonate is 0.4% by mass or less, and a breaking strength of the secondary particles is 30 MPa or more.

Cathode active material for lithium ion secondary battery, method for manufacturing cathode active material for lithium ion secondary battery, and lithium ion secondary

The present invention is to provide a cathode active material used for a lithium ion secondary battery which has a large charge-discharge capacity, and excels in charge-discharge cycle properties, output properties and productivity, and, a lithium ion secondary battery using the same. The cathode active material used for a lithium ion secondary battery comprises a lithium-transition metal composite oxide having an &#x3b1;-NaFeOtype crystal structure and represented by the following formula (1); LiNiCoMO, where, in the formula (1), M is at least one metal element other than Li, Ni and Co; and a, b, c, d and a are respectively numbers satisfying &#x2212;0.04&#x2264;a&#x2264;0.04, 0.80&#x2264;b&#x2264;1.0, 0&#x2264;c&#x2264;0.06, b+c+d=1, and &#x2212;0.2&#x3c;&#x3b1;&#x3c;0.2, and an a-axis lattice constant of the crystal structure is 2.878&#xd7;10m or more.

The object of the invention is to provide positive electrode material in which a discharge rate characteristic and battery capacity are hardly deteriorated in the environment of low temperature of &#x2212;30&#xb0; C., its manufacturing method and a lithium secondary battery using the positive electrode material. The invention is characterized by the positive electrode material in which plural primary particles are flocculated and a secondary particle is formed, and the touch length of the primary particles is equivalent to 10 to 70% of the length of the whole periphery on the section of the touched primary particles.

Positive electrode material, its manufacturing method and lithium secondary battery

A ceramics sintered compact is provided in which a relative dielectric constant and an electromechanical coupling coefficient are improved in superior balance and which shows a relatively high piezoelectric coefficient. A ceramics sintered compact having a perovskite structure is provided in which a (002)/(200) ratio by X-ray diffraction after polarization is applied is 1.0 or greater.

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Kumagaya, Japan

Genei Nakajima