Method for manufacturing lithium ion secondary battery

Patent metadata

Field	Value
Publication number	US-9583755-B2
Application number	US-201314029877-A
Country	US
Kind code	B2
Filing date	Sep 18, 2013
Priority date	Sep 19, 2012
Publication date	Feb 28, 2017
Grant date	Feb 28, 2017

Abstract

A method for manufacturing a lithium ion secondary battery having electrodes in which a mix layer including a first binder and one of a positive electrode active material and a negative electrode active material is formed via a second binder on a collector. The method includes: performing pattern coating of the second binder on the surface of the collector and regularly forming binder-coated sections and uncoated sections; and feeding a powder of mix particles on the binder-coated sections and the uncoated sections so as to form the mix layer on the collector.

First claim

What is claimed is:

1. A method for manufacturing a lithium ion secondary battery having electrodes in which a mix layer including a first binder and one of a positive electrode active material and a negative electrode active material is formed via a second binder on a collector, the method comprising:
performing pattern coating of a binder coating liquid including the second binder on a surface of the collector to regularly form binder-coated sections and uncoated sections no the collector; and
feeding a dry powder of mix particles including the positive electrode active material or the negative electrode active material and the first binder on the binder-coated sections and the uncoated sections so as to form the mix layer on the collector,
wherein:
the pattern coating is performed by intaglio gravure coating,
an intaglio gravure roll incised with a plurality of groove-shaped depressions having intersections where the grooves intersect with each other is used for the intaglio gravure coating,
the binder coating liquid supplied to the groove-shaped depressions shrinks to the intersections, and
the shrunk binder coating liquid is coated on the collector in a dot shape.

2. The manufacturing method according to claim 1 , wherein a length of the coated section in a direction parallel to a conveying direction of the collector is larger than a length in a direction perpendicular to the conveying direction.

3. The manufacturing method according to claim 1 , wherein a glass transition temperature of the second binder used for the binder coating liquid is within a range −50° C. to 30° C.

4. The manufacturing method according to claim 1 , wherein an exposed surface area ratio of the collector in the pattern coating is within a range of 10% to 85%, the exposed surface area ratio being a ratio of an exposed surface area of the collector to a total area of the collector.

5. A method for manufacturing a lithium ion secondary battery having electrodes in which a mix layer including a first binder and one of a positive electrode active material and a negative electrode active material is formed via a second binder on a collector, the method comprising:
performing pattern coating of a binder coating liquid including the second binder on a surface of the collector to regularly form binder-coated sections and uncoated sections on the collector; and
feeding a dry powder of mix particles including the positive electrode active material or the negative electrode active material and the first binder on the binder-coated sections and the uncoated sections so as to form the mix layer on the collector,
wherein:
the pattern coating is performed by intaglio gravure coating,
an intaglio gravure roll incised with a plurality of groove-shaped depressions having intersections where the grooves intersect with each other is used for the intaglio gravure coating,
the binder coating liquid supplied to the groove-shaped depressions shrinks to the intersections,
the shrunk binder coating liquid is coated on the collector in a dot shape,
the groove-shaped depressions have a shape such that grooves with a groove width of 10 μm to 40 μm, a groove pitch of 23 μm to 40 μm, and a groove depth of 5 μm to 20 μm are formed in a grid-shape pattern, and
the collector and the binder coating liquid are selected such that a contact angle formed between a tangent of a liquid drop to a surface of the collector and the surface of the collector when the binder coating liquid is dropped on the collector is equal to or greater than 50 degrees.

Assignees

• Uchida Yozo
• Suzuki Kazuhiro
• Sekine Hiroyuki
• Matsumura Taku
• Arai Kunihito
• Toyota Motor Co Ltd
• Zeon Corp

Inventors

• Uchida Yozo
• Suzuki Kazuhiro
• Sekine Hiroyuki
• Matsumura Taku
• Arai Kunihito

Classifications

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• Y02P70/54

  Cross-Sectional Technologies · mapped topic

• H01M4/0435

  Rolling or calendering · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/621

  Binders · CPC title