Thin power storage device and production method thereof

Patent metadata

Field	Value
Publication number	US-10079374-B2
Application number	US-201514829096-A
Country	US
Kind code	B2
Filing date	Aug 18, 2015
Priority date	Aug 18, 2014
Publication date	Sep 18, 2018
Grant date	Sep 18, 2018

Abstract

A power storage device includes a positive electrode part including a first metallic foil layer and a positive electrode active material layer partially laminated on one surface of the first metallic foil layer, a negative electrode part including a second metallic foil layer and a negative electrode active material layer partially laminated on one surface of the second metallic foil layer, and a separator arranged between the positive electrode part and the negative electrode part. The positive electrode active material layer is arranged between the first metallic foil layer and the separator, and the negative electrode active material layer is arranged between the second metallic foil layer and the separator. The peripheral regions of the one surfaces of the first and second metallic foil layers in which the positive and negative electrode active material layers are not formed are joined via a peripheral sealing layer containing a thermoplastic resin.

First claim

The invention claimed is:

1. A thin power storage device comprising:
a positive electrode part including a first metallic foil layer and a positive electrode active material layer laminated on a partial region of a first surface of the first metallic foil layer;
a negative electrode part including a second metallic foil layer and a negative electrode active material layer laminated on a partial region of a first surface of the second metallic foil layer; and
a separator arranged between the positive electrode part and the negative electrode part, wherein
the positive electrode active material layer is arranged between the first metallic foil layer and the separator, and the negative electrode active material layer is arranged between the second metallic foil layer and the separator;
a peripheral region of the first surface of the first metallic foil layer of the positive electrode part in which the positive electrode active material layer is not formed and a peripheral region of the first surface of the second metallic foil layer of the negative electrode part in which the negative electrode active material layer is not formed are joined via a peripheral sealing layer containing a thermoplastic resin;
a first insulation resin film is an outermost layer of the thin power storage device and is laminated on a second surface of the first metallic foil layer, which is opposite to the first surface of the first metallic foil layer, such that a portion of the second surface of the first metallic foil layer is exposed to define a first metal exposed portion;
a second insulation resin film is an outermost layer of the thin power storage device and is laminated on a second surface of the second metallic foil layer, which is opposite to the first surface of the second metallic foil layer, such that a portion of the second surface of the second metallic foil layer is exposed to define a second metal exposed portion; and
the thin power storage device has no tab nor lead wire.

2. The thin power storage device as recited in claim 1 , wherein the first insulation resin film and the second insulation resin film are each formed by a heat-resistant resin stretched film.

3. The thin power storage device as recited in claim 1 ,
wherein the positive electrode active material layer is laminated on the first surface of the first metallic foil layer via a first binder layer, and the negative electrode active material layer is laminated on the first surface of the second metallic foil layer via a second binder layer, and
wherein the first binder layer and the second binder layer are each made of at least one binder material selected from the group consisting of polyvinylidene fluoride, styrene-butadiene rubber, carboxymethyl cellulose sodium salt, and polyacrylonitrile.

4. The thin power storage device as recited in claim 1 , wherein the peripheral sealing layer is formed by a thermoplastic resin unstretched film.

5. The thin power storage device as recited in claim 1 ,
wherein an electrolyte is encapsulated between the separator and the positive electrode active material layer, and
wherein an electrolyte is encapsulated between the separator and the negative electrode active material layer.

6. The thin power storage device as recited in claim 1 ,
wherein the first metallic foil layer is formed by an aluminum foil, and
wherein the second metallic foil layer is formed by an aluminum foil, a copper foil, a stainless steel foil, a nickel foil or a titanium foil.

7. The thin power storage device as recited in claim 1 ,
wherein a first chemical conversion film is formed at least on the first surface of the first metallic foil layer to which the positive electrode active material layer is laminated, and
wherein a second chemical conversion film is formed at least on the first surface of the second metallic foil layer to which the negative electrode active material layer is laminated.

Assignees

• Showa Denko Packaging Co Ltd
• Showa Denko Kk

Inventors

• Minamitani Koji
• Minamibori Yuji
• Nagata Kensuke
• Saito Shunsuke

Classifications

• H01M10/0587

  of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators · CPC title

• H01M10/0585

  of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators · CPC title

• H01M10/0525

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

• H01M10/0436

  Small-sized flat cells or batteries for portable equipment · CPC title

• H01M10/0431

  Cells with wound or folded electrodes (H01M10/045 takes precedence) · CPC title