JP2012190680A - Flat battery, and sealing can - Google Patents

Flat battery, and sealing can Download PDF

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Publication number
JP2012190680A
JP2012190680A JP2011053915A JP2011053915A JP2012190680A JP 2012190680 A JP2012190680 A JP 2012190680A JP 2011053915 A JP2011053915 A JP 2011053915A JP 2011053915 A JP2011053915 A JP 2011053915A JP 2012190680 A JP2012190680 A JP 2012190680A
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gasket
sealing
positive electrode
flat battery
electrode
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JP5650567B2 (en
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Koji Yamaguchi
浩司 山口
Toshihiko Ishihara
俊彦 石原
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Hitachi Maxell Energy Ltd
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Hitachi Maxell Energy Ltd
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

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  • Sealing Battery Cases Or Jackets (AREA)
  • Secondary Cells (AREA)

Abstract

PROBLEM TO BE SOLVED: To prevent a sealing can from being deformed by concentration of compressive force while surely sealing the sealing can to an outer can by efficiently applying pressure to a gasket when fitting the sealing can to the outer can.SOLUTION: A flat battery includes the sealing can having a side face part equipped with a top face part and a step part expanded stepwise, an outer can having a diameter larger than that of the sealing can, a bottom part, and a side wall part, a gasket molded so as to sandwich the side face part of the sealing can, and an electrode body equipped with a positive electrode, a negative electrode, and a separator. The electrode body is disposed in a space hermetically sealed by caulking the side wall part of the outer can to the side face part of the sealing can with the gasket sandwiched, the thickness of the gasket on the inside of the side face part of the sealing can in the lower part of the step part is formed thicker than the thickness in the direction toward the electrode body from the inside face of the side face part of the sealing can in the bottom part of the outer can, and the gasket is formed so as to be separated from the top face part of the sealing can.

Description

本発明は扁平形電池の封止構造に関するものである。   The present invention relates to a flat battery sealing structure.

従来、有底筒状の外装缶と、該外装缶の開口を覆うように配置され且つ外周側で外装缶と接続される封口缶と、を備えた扁平形電池は知られている。このような扁平形電池では、例えば特許文献１、２に開示されるように、電池内部の気密性を保ち且つ外装缶と封口缶との電気的な絶縁を確保するために、外装缶と封口缶との接続部分に樹脂製のガスケットを配置している。   Conventionally, a flat battery including a bottomed cylindrical outer can and a sealing can that is disposed so as to cover the opening of the outer can and connected to the outer can on the outer peripheral side is known. In such a flat battery, for example, as disclosed in Patent Documents 1 and 2, in order to maintain airtightness inside the battery and to ensure electrical insulation between the outer can and the sealing can, A resin gasket is arranged at the connection with the can.

また、前記特許文献１、２には、前記ガスケットを封口缶の周壁部にモールド成形する構成が開示されている。特に、特許文献１には、有底筒状の封口缶の周壁部に、開口端部から階段状に折れ曲がる段部付近まで延びるようにガスケットをモールド形成する構成が開示されている。   Patent Documents 1 and 2 disclose a configuration in which the gasket is molded on the peripheral wall portion of the sealing can. In particular, Patent Document 1 discloses a configuration in which a gasket is molded on the peripheral wall portion of a bottomed cylindrical sealing can so as to extend from the opening end portion to the vicinity of a step portion that bends in a stepped manner.

特開平４−３４８３７号公報JP-A-4-34837 特開昭６１−２３３９６５号公報JP-A 61-233965

扁平形電池の場合、一般的に、外装缶と封口缶との接続は、該封口缶の周壁部に形成された段部に外装缶の開口端部を嵌合させることにより行われる。特許文献１及び特許文献２に開示されている構成のように、封口缶の周壁部の周りに樹脂製のガスケットをモールド成形した場合、封口缶の周壁部の端部に外装缶の開口端部を嵌合させる際に、該封口缶にモールド成形されたガスケットには圧縮力が加わる。
発明者の解析によるとガスケットに対する圧縮力が大きく働く箇所は、封口缶の開口端部と外装缶の底端部との間と、封口缶の段部付近と外装缶の開口端部の間である。主に、この２か所のガスケットに加わる圧縮力により、嵌合した封口缶と外装缶が密封され、漏液が防止されることになる。 In the case of a flat battery, the connection between the outer can and the sealing can is generally performed by fitting the open end of the outer can to the step formed on the peripheral wall of the sealing can. As in the configurations disclosed in Patent Document 1 and Patent Document 2, when a resin gasket is molded around the peripheral wall portion of the sealing can, the opening end portion of the outer can at the end portion of the peripheral wall portion of the sealing can , A compression force is applied to the gasket molded in the sealed can.
According to the inventor's analysis, the places where the compressive force on the gasket works greatly are between the opening end of the sealed can and the bottom end of the outer can, between the vicinity of the stepped portion of the sealing can and the opening end of the outer can. is there. Mainly, the fitted sealing can and the outer can are sealed by the compressive force applied to these two gaskets, and liquid leakage is prevented.

ガスケットの形状についても、上記の解析結果に基づいた最適な形状が求められる。封口缶と外装缶を嵌合させるにあたって、ガスケットに効率よく圧力を加えるとともに、圧縮力の集中による封口缶の変形を防止する必要がある。また、ガスケットは、封口缶の周壁部から電極等の電池要素の存在する電池内部に面する位置に形成するため、その大きさを最適化することにより、電池内部の空間を確保することが必要である。   As for the shape of the gasket, an optimum shape based on the above analysis result is required. When fitting the sealing can and the outer can, it is necessary to efficiently apply pressure to the gasket and to prevent deformation of the sealing can due to concentration of compressive force. In addition, since the gasket is formed from the peripheral wall of the sealing can at the position facing the inside of the battery where the battery elements such as electrodes are present, it is necessary to secure the space inside the battery by optimizing the size. It is.

本発明は、ガスケットの形状を最適化することにより、封口缶と外装缶の封止構造における信頼性を向上させることを目的とする。   An object of this invention is to improve the reliability in the sealing structure of a sealing can and an exterior can by optimizing the shape of a gasket.

上記の課題を解決するために本発明は以下の構成とする。
上面部と、段状に広がる段部を備えた側面部とを有する封口缶と、前記封口缶よりも外径が大きく、底部と側壁部とを有する外装缶と、前記封口缶の側面部を挟み込むようにモールド形成されるガスケットと、正極、負極及びセパレータを備える電極体と、を備えた扁平形電池であって、前記電極体は、前記封口缶の側面部に対し前記外装缶の側壁部を前記ガスケットを挟んでかしめることにより密閉される空間に配置され、前記段部の下方における前記ガスケットの前記封口缶の側面部内側の厚みは、前記外装缶の底部における前記封口缶の側面部内側の面から前記電極体方向への厚みよりも大きく形成され、前記ガスケットは前記封口缶の上面部から分離されて形成される構成とする。 In order to solve the above problems, the present invention has the following configuration.
A sealing can having an upper surface portion and a side portion provided with a stepped portion that spreads stepwise, an outer can larger in outer diameter than the sealing can, having a bottom portion and a side wall portion, and a side portion of the sealing can A flat battery comprising a gasket molded so as to be sandwiched and an electrode body including a positive electrode, a negative electrode, and a separator, wherein the electrode body is a side wall portion of the outer can with respect to a side surface portion of the sealed can Is disposed in a space that is sealed by caulking the gasket, and the thickness inside the side surface of the sealing can of the gasket below the stepped portion is the side surface of the sealing can at the bottom of the outer can The gasket is formed to be larger than the thickness in the direction of the electrode body from the inner surface, and the gasket is formed separately from the upper surface portion of the sealing can.

本発明の扁平形電池及び封口缶により、封口缶と外装缶の封止構造における信頼性を向上させることができる。   With the flat battery and the sealing can of the present invention, the reliability in the sealing structure of the sealing can and the outer can can be improved.

本発明の第1の実施形態における扁平形電池の概略図Schematic of the flat battery in the first embodiment of the present invention 本発明の第1の実施形態における扁平形電池の封止構造を示す図The figure which shows the sealing structure of the flat battery in the 1st Embodiment of this invention 本発明の第1の実施形態における封口缶とガスケットの拡大図Enlarged view of the sealing can and gasket in the first embodiment of the present invention 本発明の第1の実施形態におけるガスケットの形成方法を示す図The figure which shows the formation method of the gasket in the 1st Embodiment of this invention 本発明の第２の実施形態における扁平形電池の封止構造を示す図The figure which shows the sealing structure of the flat battery in the 2nd Embodiment of this invention. 本発明の第２の実施形態における封口缶とガスケットの拡大図The enlarged view of the sealing can and gasket in the 2nd Embodiment of this invention 本発明の第３の実施形態における封口缶とガスケットの拡大図The enlarged view of the sealing can and gasket in the 3rd Embodiment of this invention

以下、図面を参照し、本発明の実施の形態を詳しく説明する。図中の同一または相当部分については同一の符号を付してその説明は繰り返さない。   Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals and description thereof will not be repeated.

（実施形態１）
図１から図４は本発明の第１の実施形態を示す。
（全体構成）
図１は、本発明の第１の実施形態である扁平形電池１の概略構成を示す断面図である。この扁平形電池１は、有底円筒状の外装缶としての負極缶１０と、該負極缶１０の開口を覆う封口缶としての正極缶２０と、負極缶１０の外周側と正極缶２０の外周側との間に配置されるガスケット３０と、負極缶１０及び正極缶２０の間に形成される空間内に収納される電極体４０とを備えている。したがって、扁平形電池１は、負極缶１０と正極缶２０とを合わせることによって、全体が扁平なコイン状となる。扁平形電池１の負極缶１０及び正極缶２０の間に形成される空間内には、電極体４０以外に、非水電解液（図示省略）も封入されている。 (Embodiment 1)
1 to 4 show a first embodiment of the present invention.
(overall structure)
FIG. 1 is a cross-sectional view showing a schematic configuration of a flat battery 1 according to the first embodiment of the present invention. The flat battery 1 includes a negative electrode can 10 as a bottomed cylindrical outer can, a positive electrode can 20 as a sealing can covering the opening of the negative electrode can 10, an outer peripheral side of the negative electrode can 10, and an outer periphery of the positive electrode can 20. A gasket 30 disposed between the electrode can 40 and an electrode body 40 accommodated in a space formed between the negative electrode can 10 and the positive electrode can 20. Therefore, the flat battery 1 is formed into a flat coin shape by combining the negative electrode can 10 and the positive electrode can 20 together. In the space formed between the negative electrode can 10 and the positive electrode can 20 of the flat battery 1, in addition to the electrode body 40, a non-aqueous electrolyte (not shown) is also enclosed.

負極缶１０は、ステンレスなどの金属材料からなり、プレス成形によって有底円筒状に形成されている。負極缶１０は、円形状の底部１１と、その外周に該底部１１と連続して形成される円筒状の周壁部１２（側壁部）とを備えている。この周壁部１２は、縦断面視（図１に図示した状態）で、底部１１の外周端からほぼ垂直に延びるように設けられている。負極缶１０は、後述するように、正極缶２０との間にガスケット３０を挟んだ状態で、周壁部１２の開口端側が内側に折り曲げられて、該正極缶２０に対してかしめられている。なお、負極缶１０には、プレス成形によって折り曲げられた部分（例えば、底部１１と周壁部１２との間の部分など）に、それぞれ、曲面を有するＲ部分が形成されている。   The negative electrode can 10 is made of a metal material such as stainless steel and is formed into a bottomed cylindrical shape by press molding. The negative electrode can 10 includes a circular bottom portion 11 and a cylindrical peripheral wall portion 12 (side wall portion) formed continuously with the bottom portion 11 on the outer periphery thereof. The peripheral wall portion 12 is provided so as to extend substantially vertically from the outer peripheral end of the bottom portion 11 in a longitudinal sectional view (the state illustrated in FIG. 1). As will be described later, the negative electrode can 10 is crimped to the positive electrode can 20 by bending the opening end side of the peripheral wall portion 12 inward with a gasket 30 sandwiched between the negative electrode can 20 and the positive electrode can 20. The negative electrode can 10 is formed with R portions each having a curved surface in a portion bent by press molding (for example, a portion between the bottom portion 11 and the peripheral wall portion 12).

正極缶２０も、負極缶１０と同様、ステンレスなどの金属材料からなり、プレス成形によって有底円筒状に形成されている。正極缶２０は、負極缶１０の周壁部１２よりも外形が小さい円筒状の周壁部２２（側面部）と、その一方の開口を塞ぐ円形状の平面部２１と、を有している。この周壁部２２も、負極缶１０と同様、縦断面視で、平面部２１（上面部）に対してほぼ垂直に延びるように設けられている。周壁部２２には、平面部２１側の基端部２２ａに比べて径が段状に大きくなる拡径部２２ｂが形成されている。すなわち、周壁部２２には、基端部２２ａと拡径部２２ｂとの間に段部２２ｃが形成されている。図１に示すように、この段部２２ｃに対して、負極缶１０の周壁部１２の開口端側が折り曲げられてかしめられている。すなわち、負極缶１０は、その周壁部１２の開口端側が正極缶２０の段部２２ｃに嵌合されている。なお、この正極缶２０も、プレス成形によって折り曲げられている部分（例えば、平面部２１と周壁部２２との間の部分や、段部２２ｃなど）には、それぞれ、曲面を有するＲ部分が形成されている。   Similarly to the negative electrode can 10, the positive electrode can 20 is also made of a metal material such as stainless steel, and is formed into a bottomed cylindrical shape by press molding. The positive electrode can 20 has a cylindrical peripheral wall portion 22 (side surface portion) whose outer shape is smaller than that of the peripheral wall portion 12 of the negative electrode can 10, and a circular flat portion 21 that closes one of the openings. Similar to the negative electrode can 10, the peripheral wall portion 22 is also provided so as to extend substantially perpendicular to the flat surface portion 21 (upper surface portion) in a longitudinal sectional view. The peripheral wall portion 22 is formed with an enlarged diameter portion 22b whose diameter is increased stepwise compared to the base end portion 22a on the flat surface portion 21 side. That is, the peripheral wall portion 22 is formed with a step portion 22c between the base end portion 22a and the enlarged diameter portion 22b. As shown in FIG. 1, the open end side of the peripheral wall portion 12 of the negative electrode can 10 is bent and caulked with respect to the step portion 22c. That is, the negative electrode can 10 has the opening end side of the peripheral wall portion 12 fitted to the step portion 22 c of the positive electrode can 20. In addition, the positive electrode can 20 is also formed with an R portion having a curved surface in a portion bent by press molding (for example, a portion between the flat portion 21 and the peripheral wall portion 22 or a step portion 22c). Has been.

ガスケット３０は、ポリプロピレン（ＰＰ）からなる。ガスケット３０は、負極缶１０の周壁部１２と正極缶２０の周壁部２２との間に挟みこまれるように、該正極缶２０の周壁部２２にモールド成形されている。ガスケット３０の詳しい構成については後述する。なお、ガスケット３０の材料としては、ＰＰに限らず、ポリフェニレンサルファイド（ＰＰＳ）にオレフィン系エラストマーを含有した樹脂組成物や、ポリテトラフルオロエチレン（ＰＦＡ）、ポリアミド系樹脂などを用いてもよい。   The gasket 30 is made of polypropylene (PP). The gasket 30 is molded on the peripheral wall portion 22 of the positive electrode can 20 so as to be sandwiched between the peripheral wall portion 12 of the negative electrode can 10 and the peripheral wall portion 22 of the positive electrode can 20. The detailed configuration of the gasket 30 will be described later. The material of the gasket 30 is not limited to PP, and a resin composition containing an olefin elastomer in polyphenylene sulfide (PPS), polytetrafluoroethylene (PFA), a polyamide resin, or the like may be used.

本発明の実施の形態１の電極体４０は、円板状の正極４１と略円板状の負極４６と正極４１と負極４６の間に配置されるセパレータ４４を有する単層型の電極構造である。
正極４１は、コバルト酸リチウム等の正極活物質を含有する正極活物質層を、アルミニウム等の金属箔製の正極集電体に塗布したものである。正極４１は正極缶２０に接触して配置される。 The electrode body 40 according to the first embodiment of the present invention has a single-layer electrode structure having a disk-shaped positive electrode 41, a substantially disk-shaped negative electrode 46, and a separator 44 disposed between the positive electrode 41 and the negative electrode 46. is there.
The positive electrode 41 is obtained by applying a positive electrode active material layer containing a positive electrode active material such as lithium cobaltate to a positive electrode current collector made of metal foil such as aluminum. The positive electrode 41 is disposed in contact with the positive electrode can 20.

負極４６は、黒鉛等の負極活物質を含有する負極活物質層を、銅等の金属箔製の負極集電体に塗布したものである。負極４６は負極缶１０に接触して配置される。
セパレータ４４は、円形状の部材であり、正極４１と負極４６を分離するとともに、負極４６を覆うように配置されることで、負極４６が正極缶２０に触れることによる短絡を防止している。セパレータ４４は、絶縁性に優れたポリエチレン製の微多孔性薄膜によって構成されている。このように、セパレータ４４を微多孔性薄膜によって構成することで、リチウムイオンが該セパレータ４４を透過することができる。 The negative electrode 46 is obtained by applying a negative electrode active material layer containing a negative electrode active material such as graphite to a negative electrode current collector made of metal foil such as copper. The negative electrode 46 is disposed in contact with the negative electrode can 10.
The separator 44 is a circular member, and separates the positive electrode 41 and the negative electrode 46 and is disposed so as to cover the negative electrode 46, thereby preventing a short circuit due to the negative electrode 46 touching the positive electrode can 20. The separator 44 is constituted by a microporous thin film made of polyethylene having excellent insulating properties. Thus, by forming the separator 44 with a microporous thin film, lithium ions can pass through the separator 44.

（ガスケットの構成）
図１から図３に示すように、ガスケット３０は、正極缶２０の周壁部２２を包み込むように概略円筒状に形成されている。詳しくは、ガスケット３０は、周壁部２２の正極缶内方側、及び、該周壁部２２における段部２２ｃ及び拡径部２２ｂのそれぞれの正極缶外方側を覆うように、正極缶２０にモールド成形されている。すなわち、ガスケット３０は、周壁部２２の正極缶内方を覆うガスケット内側部３１と、該周壁部２２の外方を覆うガスケット外側部３２と、該周壁部２２の開口端部の先端を覆うガスケット先端部３３とを有している。 (Gasket configuration)
As shown in FIGS. 1 to 3, the gasket 30 is formed in a substantially cylindrical shape so as to wrap around the peripheral wall portion 22 of the positive electrode can 20. Specifically, the gasket 30 is molded on the positive electrode can 20 so as to cover the inner side of the peripheral wall portion 22 and the outer side of the stepped portion 22c and the enlarged diameter portion 22b of the peripheral wall portion 22. Molded. That is, the gasket 30 includes a gasket inner portion 31 that covers the inside of the positive electrode can of the peripheral wall portion 22, a gasket outer portion 32 that covers the outer portion of the peripheral wall portion 22, and a gasket that covers the tip of the open end of the peripheral wall portion 22. And a distal end portion 33.

図２は、図１の扁平形電池１における封止部分の拡大図である。正極缶２０にモールド成形されたガスケット３０を介して、負極缶が正極缶にかしめられており、ガスケット３０には圧縮力が加えられる。この圧縮力はガスケット３０に一様に働くものではなく、その形状により、圧縮力が主に大きく働く箇所が２か所ある。封口缶の開口端部と外装缶の底端部（底のＲ部）との間（点線部ａ）と、封口缶の段部２２ｃ付近と外装缶の開口端部の間（点線部ｂ）である。圧縮力が大きく、正極缶２０及び負極缶１０のこれらの箇所に面する部分の圧力（面圧）は大きくなり、扁平形電池１を密閉している。   FIG. 2 is an enlarged view of a sealing portion in the flat battery 1 of FIG. The negative electrode can is caulked to the positive electrode can through the gasket 30 molded in the positive electrode can 20, and a compressive force is applied to the gasket 30. This compressive force does not work uniformly on the gasket 30, and there are two places where the compressive force mainly works greatly depending on its shape. Between the opening end of the sealing can and the bottom end (R portion of the bottom) of the outer can (dotted line part a), between the vicinity of the step 22c of the sealing can and the opening end of the outer can (dotted line part b) It is. The compressive force is large, and the pressure (surface pressure) at the portions of the positive electrode can 20 and the negative electrode can 10 facing these portions is increased, and the flat battery 1 is sealed.

図３に示すように、ガスケット内側部３１は、正極缶２０の段部２２ｃの下面から該正極缶２０の周壁部２２の開口端側に亘って略円筒状に形成されている。ガスケット内側部３１は、周壁部２２の段部２２ｃの正極缶内方に位置するガスケット上部３１ａと、該周壁部２２の拡径部２２ｂの正極缶内方に位置するガスケット下部３１ｂと、を有している。また、ガスケット内側部３１は、正極缶２０の周壁部２２の開口端側へ向かうほど、内径が大きくなるように、すなわち内面が周壁部２２に近づくように、全体としてテーパ状に形成されている。ガスケット内側部３１の厚みは周壁部２２の段部２２ｃの下方の厚み（Ｂに相当）が、ガスケット先端部３３における正極缶の周壁部２２の内側部分の厚み（Ａに相当）よりも大きい。これは下記の理由による。   As shown in FIG. 3, the gasket inner portion 31 is formed in a substantially cylindrical shape from the lower surface of the step portion 22 c of the positive electrode can 20 to the opening end side of the peripheral wall portion 22 of the positive electrode can 20. The gasket inner portion 31 includes a gasket upper portion 31a located inside the positive electrode can of the step portion 22c of the peripheral wall portion 22, and a gasket lower portion 31b located inside the positive electrode can of the enlarged diameter portion 22b of the peripheral wall portion 22. is doing. Further, the gasket inner portion 31 is formed in a tapered shape as a whole so that the inner diameter becomes larger toward the opening end side of the peripheral wall portion 22 of the positive electrode can 20, that is, the inner surface approaches the peripheral wall portion 22. . As for the thickness of the gasket inner portion 31, the thickness (corresponding to B) below the step portion 22 c of the peripheral wall portion 22 is larger than the thickness (corresponding to A) of the inner portion of the peripheral wall portion 22 of the positive electrode can at the gasket tip portion 33. This is due to the following reasons.

正極缶２０の段部２２ｃには、負極缶側からガスケット３０を介してかしめることによる大きな力が作用する。段部２２ｃは正極缶をプレス成形により階段状して成形されるが、この部分に大きな力が集中すると、形成された段部２２ｃが変形してしまうおそれがある。そこで、段部２２ｃの下面に位置するガスケット３０は出来る限り厚みを大きくすることにより、負極缶１０から作用する力に対抗することができる。   A large force is applied to the step portion 22 c of the positive electrode can 20 by caulking through the gasket 30 from the negative electrode can side. The step portion 22c is formed by stepping the positive electrode can by press molding. However, if a large force is concentrated on this portion, the formed step portion 22c may be deformed. Therefore, the gasket 30 positioned on the lower surface of the stepped portion 22c can counter the force acting from the negative electrode can 10 by increasing the thickness as much as possible.

しかし、段部２２ｃの下方に位置するガスケットの厚みを均一に大きくすると、十分な封止強度をえるためにはより大きな圧力が必要となる。すなわち、負極缶１０の底部１１に面するガスケット先端部３３の面積が大きくなると、封止時の圧力を大きくしなければ十分な強度を得ることはできない。解析によると、ガスケット先端部３３では特に図２の点線部ａで示す部分に圧縮力が集中し、正極缶２０の周壁部２２の内側（電極体側）には圧縮力が集中しない。電池缶自体の密閉度を高めるためには、構造上、点線部ａの部分に圧縮力を集中させるのがよく、より確実に密閉することが可能となる。正極缶２０に対し負極缶１０をかしめることにより負極缶の底部１１からガスケット先端部３３の全体に力が加わる。圧縮力を効率よく点線部ａに集中させるためには、ガスケット先端部３３において、できる限り周壁部２２から内側の領域（図３中のＡに相当する部分）を小さくし、力の分散を避けるようにする。   However, if the thickness of the gasket located below the step portion 22c is uniformly increased, a larger pressure is required to obtain sufficient sealing strength. That is, if the area of the gasket tip 33 facing the bottom 11 of the negative electrode can 10 is increased, sufficient strength cannot be obtained unless the pressure at the time of sealing is increased. According to the analysis, the compressive force concentrates particularly on the gasket tip 33 at the portion indicated by the dotted line a in FIG. 2, and the compressive force does not concentrate on the inner side (electrode body side) of the peripheral wall portion 22 of the positive electrode can 20. In order to increase the sealing degree of the battery can itself, it is better to concentrate the compressive force on the portion indicated by the dotted line a in terms of the structure, and the sealing can be performed more reliably. By caulking the negative electrode can 10 against the positive electrode can 20, a force is applied from the bottom 11 of the negative electrode can to the entire gasket tip 33. In order to efficiently concentrate the compressive force on the dotted line portion a, the gasket tip 33 is made as small as possible from the peripheral wall 22 to the inner region (portion corresponding to A in FIG. 3) to avoid force dispersion. Like that.

上記の理由により、ガスケット内側部３１の上部（段部２２ｃの下面）の厚みを大きくし、ガスケット内側部３１の下部（負極缶１０の底部の上面）の厚みを小さくすることとなり、ガスケット内側部３１は図３のようにＢ＞Ａの厚みとし、テーパ状に形成されることになる。   For the above reasons, the thickness of the upper portion of the gasket inner portion 31 (the lower surface of the step portion 22c) is increased, and the thickness of the lower portion of the gasket inner portion 31 (the upper surface of the bottom portion of the negative electrode can 10) is decreased. 31 has a thickness of B> A as shown in FIG. 3, and is formed in a tapered shape.

また、本実施の形態においてガスケット内側部３１は段部２２ｃの下面から負極缶１０の底部１１にかけて形成される。ガスケット上部３１ａの端部と正極缶２０の平面部との間には基端部２２ａが存在し、ガスケット上部３１ａと正極缶２０の平面部とは直接は接触せず分離されている。ガスケット内側部３１は、周壁部２２の基端部２２ａの表面からガスケット表面が連続したテーパ状となるように形成される。   Further, in the present embodiment, the gasket inner portion 31 is formed from the lower surface of the step portion 22 c to the bottom portion 11 of the negative electrode can 10. A base end portion 22a exists between the end portion of the gasket upper portion 31a and the flat portion of the positive electrode can 20, and the gasket upper portion 31a and the flat portion of the positive electrode can 20 are separated without being in direct contact with each other. The gasket inner portion 31 is formed so that the gasket surface is tapered from the surface of the base end portion 22a of the peripheral wall portion 22.

これにより、正極缶２０の周壁部２２の段部２２ｃに対して負極缶１０の周壁部１２をかしめた際に、ガスケット下部３１ｂが圧縮されてガスケット上部３１ａに力が加わった場合でも、該ガスケット上部３１ａが正極缶２０の平面部と接触していない。そのため、ガスケット下部からの力を、ガスケット上部３１ａを段部２２ｃに沿ってのわずかに変形させることによって逃がすことができる。即ち、ガスケット上部３１ａと正極缶２０の平面部を分離することで、ガスケット上部３１ａと正極缶２０の平面部と干渉によるガスケット上部３１ａの剥離を防止することができる。   Accordingly, even when the gasket lower portion 31b is compressed and a force is applied to the gasket upper portion 31a when the peripheral wall portion 12 of the negative electrode can 10 is caulked against the step portion 22c of the peripheral wall portion 22 of the positive electrode can 20, the gasket is applied. The upper part 31 a is not in contact with the flat part of the positive electrode can 20. Therefore, the force from the gasket lower portion can be released by slightly deforming the gasket upper portion 31a along the step portion 22c. That is, by separating the gasket upper portion 31 a and the flat portion of the positive electrode can 20, it is possible to prevent the gasket upper portion 31 a from being peeled off due to interference between the gasket upper portion 31 a and the positive electrode can 20.

上記のような構成とすることで、正極缶２０の強度を維持しながら、適切な圧力で十分な密閉構造とすることができる。また、ガスケット内側部３１の不要な部分を削除することができ、電池缶内の空間を確保することができる。これにより、電極等の電池要素が占める空間の大きさを大きくすることができ電池容量を増加することができる。   By setting it as the above structures, it can be set as sufficient sealed structure with a suitable pressure, maintaining the intensity | strength of the positive electrode can 20. FIG. Moreover, the unnecessary part of the gasket inner side part 31 can be deleted, and the space in a battery can can be ensured. Thereby, the magnitude | size of the space which battery elements, such as an electrode, occupy can be enlarged, and battery capacity can be increased.

（扁平形電池の製造方法）
次に、上述のような構成を有する扁平形電池１の製造方法を説明する。
まず、プレス成形によって、負極缶１０及び正極缶２０をそれぞれ形成する。
一方、セパレータ４４によって分離された板状の正極４１と、板状の負極４６とを厚み方向に積層して、電極体４０を構成する。 (Manufacturing method of flat battery)
Next, a method for manufacturing the flat battery 1 having the above-described configuration will be described.
First, the negative electrode can 10 and the positive electrode can 20 are each formed by press molding.
On the other hand, the plate-like positive electrode 41 separated by the separator 44 and the plate-like negative electrode 46 are laminated in the thickness direction to constitute the electrode body 40.

正極缶２０にガスケット３０をモールド成形する様子を、図４を用いて説明する。
図４に示すように、固定成形型６１と、可動成形型６２と、リング状の断面を有するピストン可動成形型６３とを正極缶２０の外側に配置し、ピン６４を該正極缶２０の内側に配置する。これにより、これらの成形型６１，６２，６３及びピン６４によって、正極缶２０の周壁部２２の周りにガスケット３０を形成するための空間が形成される。この空間内に外部から樹脂を注入して硬化させる。 The manner in which the gasket 30 is molded on the positive electrode can 20 will be described with reference to FIG.
As shown in FIG. 4, a fixed mold 61, a movable mold 62, and a piston movable mold 63 having a ring-shaped cross section are arranged outside the positive electrode can 20, and pins 64 are arranged inside the positive electrode can 20. To place. As a result, a space for forming the gasket 30 is formed around the peripheral wall portion 22 of the positive electrode can 20 by the molds 61, 62, 63 and the pins 64. A resin is injected into the space from the outside and cured.

樹脂が硬化してガスケット３０が成形された後、まず、可動成形型６２を取り外す。そして、ピストン可動成形型６３をピン６４の軸方向（図８中の白抜き矢印方向）に移動させることにより、ガスケット３０がモールド成形された正極缶２０を該ピン６４及び固定成形型６１から脱離させることができる。   After the resin is cured and the gasket 30 is molded, first, the movable mold 62 is removed. Then, by moving the piston movable mold 63 in the axial direction of the pin 64 (in the direction of the white arrow in FIG. 8), the positive electrode can 20 in which the gasket 30 is molded is removed from the pin 64 and the fixed mold 61. Can be separated.

ここで、固定成形型６１は、ガスケット外側部３２の外周面を成形する部分が、正極缶２０の周壁部２２の段部２２ｃに向かって徐々に内径が大きくなるようなテーパ状に形成されている。これにより、上述のようにピストン可動成形型６３によってガスケット先端部３３を押した場合に、固定成形型６１から正極缶２０を容易に脱離させることができる。   Here, the fixed mold 61 is formed in a taper shape such that the portion that forms the outer peripheral surface of the gasket outer portion 32 gradually increases in inner diameter toward the step portion 22 c of the peripheral wall portion 22 of the positive electrode can 20. Yes. Thus, when the gasket tip 33 is pushed by the piston movable mold 63 as described above, the positive electrode can 20 can be easily detached from the fixed mold 61.

また、ピン６４は、正極缶２０の基端部２２ａの内周に接しており、開口部２２ｃに向かって徐々に内系が大きくなるように形成されている。これにより、ガスケット内側部３１は、周壁部２２の基端部２２ａの表面からガスケット表面が連続したテーパ状となるように形成される。また、ピン６４から正極缶２０をスムーズに脱離させることができる。
上述のようにしてガスケット３０がモールド成形された正極缶２０を、平面部２１が下側になるように配置し、該平面部２１に、電極体４０を接触させる。その後、該正極缶２０の内側に、非水電解液を注入する。そして、正極缶２０の開口を覆うように負極缶１０を被せる。その後、負極缶１０の周壁部１２の開口端部を、正極缶２０の周壁部２２の段部２２ｃで内方に折り曲げてかしめる。これにより、上述の構成の扁平形電池１が得られる。ここで、非水電解液は、例えば、エチレンカーボネートとメチルエチルカーボネートとを混合した溶媒に、ＬｉＰＦ６を溶解させることにより得られる。 Further, the pin 64 is in contact with the inner periphery of the base end portion 22a of the positive electrode can 20, and is formed so that the inner system gradually increases toward the opening portion 22c. Thereby, the gasket inner side part 31 is formed so that the gasket surface may become the taper shape from which the surface of the base end part 22a of the surrounding wall part 22 continued. Further, the positive electrode can 20 can be smoothly detached from the pin 64.
The positive electrode can 20 in which the gasket 30 is molded as described above is disposed so that the flat surface portion 21 is on the lower side, and the electrode body 40 is brought into contact with the flat surface portion 21. Thereafter, a non-aqueous electrolyte is injected into the positive electrode can 20. And the negative electrode can 10 is covered so that the opening of the positive electrode can 20 may be covered. Thereafter, the opening end portion of the peripheral wall portion 12 of the negative electrode can 10 is bent and crimped inward by the step portion 22 c of the peripheral wall portion 22 of the positive electrode can 20. Thereby, the flat battery 1 of the above-mentioned structure is obtained. Here, the nonaqueous electrolytic solution can be obtained, for example, by dissolving LiPF6 in a solvent obtained by mixing ethylene carbonate and methyl ethyl carbonate.

（実施形態２）
図５〜図６により本発明の第２の実施形態を説明する。
図５に示す扁平形電池２は正極缶２０、負極缶１０、電極体４０及びガスケット３０により構成される。電極体４０は、第１の実施形態とは異なり袋状のセパレータ４４内に収容された略円板状の正極４１と、略円板状の負極４６と、を厚み方向に交互に複数、積層してなる構造である。正極缶２０及び負極缶１０の構成は第１の実施形態と同様である。
電極体４０は、全体として略円柱状の形状を有している。また、電極体４０は、両端面が負極になるように、複数の正極４１及び負極４６が積層されている。 (Embodiment 2)
A second embodiment of the present invention will be described with reference to FIGS.
The flat battery 2 shown in FIG. 5 includes a positive electrode can 20, a negative electrode can 10, an electrode body 40, and a gasket 30. Unlike the first embodiment, the electrode body 40 is formed by laminating a plurality of substantially disc-shaped positive electrodes 41 and substantially disc-shaped negative electrodes 46 accommodated in a bag-shaped separator 44 in the thickness direction. This structure is The configurations of the positive electrode can 20 and the negative electrode can 10 are the same as those in the first embodiment.
The electrode body 40 has a substantially cylindrical shape as a whole. In addition, the electrode body 40 has a plurality of positive electrodes 41 and negative electrodes 46 stacked so that both end faces are negative electrodes.

正極４１は、コバルト酸リチウム等の正極活物質を含有する正極活物質層４２を、アルミニウム等の金属箔製の正極集電体４３の両面に配置したものである。   The positive electrode 41 is obtained by arranging positive electrode active material layers 42 containing a positive electrode active material such as lithium cobaltate on both surfaces of a positive electrode current collector 43 made of a metal foil such as aluminum.

負極４６は、黒鉛等の負極活物質を含有する負極活物質層４７を、銅等の金属箔製の負極集電体４８の両面にそれぞれ配置したものである。略円柱状の電極体４０の軸方向両端に位置する負極は、それぞれ、負極集電体４８，４８が電極体４０の軸方向端部に位置するように、負極集電体４８の一面側にのみ負極活物質層４７を有している。すなわち、略円柱状の電極体４０は、その両端に負極集電体４８，４８が露出している。この電極体４０の一方の負極集電体４８は、該電極体４０が負極缶１０と正極缶２０との間に配置された状態で、該負極缶１０の底部１１に当接する。電極体４０の他方の負極集電体４８は、絶縁シート４９を介して正極缶２０の平面部２１上に位置づけられる。   The negative electrode 46 is formed by disposing negative electrode active material layers 47 containing a negative electrode active material such as graphite on both surfaces of a negative electrode current collector 48 made of a metal foil such as copper. The negative electrodes located at both ends in the axial direction of the substantially cylindrical electrode body 40 are arranged on one surface side of the negative electrode current collector 48 so that the negative electrode current collectors 48 are located at the axial ends of the electrode body 40, respectively. Only the negative electrode active material layer 47 is provided. That is, the negative electrode current collectors 48 are exposed at both ends of the substantially cylindrical electrode body 40. One negative electrode current collector 48 of the electrode body 40 contacts the bottom 11 of the negative electrode can 10 in a state where the electrode body 40 is disposed between the negative electrode can 10 and the positive electrode can 20. The other negative electrode current collector 48 of the electrode body 40 is positioned on the flat surface portion 21 of the positive electrode can 20 via the insulating sheet 49.

セパレータ４４は、平面視で円形状に形成された袋状の部材であり、略円板状の正極４１を収納可能な大きさに形成されている。セパレータ４４は、絶縁性に優れたポリエチレン製の微多孔性薄膜によって構成されている。このように、セパレータ４４を微多孔性薄膜によって構成することで、リチウムイオンが該セパレータ４４を透過することができる。セパレータ４４は、一枚の長方形状の微多孔性薄膜のシート材によって正極４１を包み込んで、該シート材の重なっている部分を熱溶着等によって接着することにより形成される。   The separator 44 is a bag-shaped member formed in a circular shape in plan view, and is formed in a size that can accommodate the substantially disc-shaped positive electrode 41. The separator 44 is constituted by a microporous thin film made of polyethylene having excellent insulating properties. Thus, by forming the separator 44 with a microporous thin film, lithium ions can pass through the separator 44. The separator 44 is formed by wrapping the positive electrode 41 with a single sheet of a rectangular microporous thin film and bonding the overlapping portions of the sheet material by thermal welding or the like.

正極４１の正極集電体４３には、平面視で該正極集電体４３の外方に向かって延びる導電性の正極リード５１が一体形成されている。この正極リード５１の正極集電体４３側も、セパレータ４４によって覆われている。   The positive electrode current collector 43 of the positive electrode 41 is integrally formed with a conductive positive electrode lead 51 extending outward from the positive electrode current collector 43 in a plan view. The positive electrode current collector 43 side of the positive electrode lead 51 is also covered with the separator 44.

負極４６の負極集電体４８には、平面視で該負極集電体４８の外方に向かって延びる導電性の負極リード５２が一体形成されている。   The negative electrode current collector 48 of the negative electrode 46 is integrally formed with a conductive negative electrode lead 52 extending outward from the negative electrode current collector 48 in plan view.

図５に示すように、正極４１及び負極４６は、各正極４１の正極リード５１が一方の側に位置し、且つ、各負極４６の負極リード５２が該正極リード５１とは反対側に位置するように、積層される。   As shown in FIG. 5, in the positive electrode 41 and the negative electrode 46, the positive electrode lead 51 of each positive electrode 41 is located on one side, and the negative electrode lead 52 of each negative electrode 46 is located on the opposite side to the positive electrode lead 51. So that they are laminated.

上述のように複数の正極４１及び負極４６を厚み方向に積層した状態で、複数の正極リード５１は、先端側を厚み方向に重ね合わされて、超音波溶接等によって正極缶２０の平面部２１に接続される。これにより、複数の正極リード５１を介して複数の正極４１と正極缶２０の平面部２１とが電気的に接続される。一方、複数の負極リード５２も、先端側を厚み方向に重ね合わされて超音波溶接等によって互いに接続される。これにより、複数の負極リード５２を介して複数の負極４６が互いに電気的に接続される。   As described above, in the state where the plurality of positive electrodes 41 and the negative electrodes 46 are laminated in the thickness direction, the plurality of positive electrode leads 51 are overlapped in the thickness direction on the tip side, and are applied to the flat portion 21 of the positive electrode can 20 by ultrasonic welding or the like. Connected. As a result, the plurality of positive electrodes 41 and the flat portion 21 of the positive electrode can 20 are electrically connected via the plurality of positive electrode leads 51. On the other hand, the plurality of negative electrode leads 52 are also connected to each other by ultrasonic welding or the like with the distal end side overlapped in the thickness direction. Thereby, the plurality of negative electrodes 46 are electrically connected to each other via the plurality of negative electrode leads 52.

上述のような構成の電極体４０では、負極リード５２と正極缶２０との接触が生じる可能性がある。そのため、本実施形態では、図５及び図６に示すように、負極缶１０の周壁部１２よりも内方に位置付けられる正極缶２０の周壁部２２の内面にガスケット３０が設けられている。このガスケット３０によって、電極体４０と負極缶１０との短絡、及び、電極体４０と正極缶２０との短絡がそれぞれ防止される。   In the electrode body 40 configured as described above, the negative electrode lead 52 and the positive electrode can 20 may come into contact with each other. Therefore, in this embodiment, as shown in FIGS. 5 and 6, the gasket 30 is provided on the inner surface of the peripheral wall portion 22 of the positive electrode can 20 positioned inward of the peripheral wall portion 12 of the negative electrode can 10. The gasket 30 prevents a short circuit between the electrode body 40 and the negative electrode can 10 and a short circuit between the electrode body 40 and the positive electrode can 20.

図６は正極缶２０及びガスケット３０の形状を示す。ガスケット上部３１ａは、正極缶２０の平面部側の端部が、平面部２１と周壁部２２との間のＲ部２３の付近に達するような厚みに形成されている。ガスケット上部３１ａの端部と正極缶２０の平面部との間には空間が存在し、ガスケット上部３１ａと正極缶２０の平面部とは直接は接触せず分離されている。   FIG. 6 shows the shapes of the positive electrode can 20 and the gasket 30. The gasket upper portion 31 a is formed to have a thickness such that the end portion on the flat portion side of the positive electrode can 20 reaches the vicinity of the R portion 23 between the flat portion 21 and the peripheral wall portion 22. There is a space between the end portion of the gasket upper portion 31a and the flat portion of the positive electrode can 20, and the gasket upper portion 31a and the flat portion of the positive electrode can 20 are separated without being in direct contact with each other.

これにより、正極缶２０の周壁部２２の段部２２ｃに対して負極缶１０の周壁部１２をかしめた際に、ガスケット下部３１ｂが圧縮されてガスケット上部３１ａに力が加わった場合でも、該ガスケット上部３１ａが正極缶２０の平面部と接触していないため、ガスケット下部からの力をガスケット上部３１ａのわずかな変形によって逃がすことができる。即ち、ガスケット上部３１ａと正極缶２０の平面部との間にわずかな空間を設けることで、ガスケット上部３１ａと正極缶２０の平面部と干渉によるガスケット上部３１ａの剥離を防止することができる。   Accordingly, even when the gasket lower portion 31b is compressed and a force is applied to the gasket upper portion 31a when the peripheral wall portion 12 of the negative electrode can 10 is caulked against the step portion 22c of the peripheral wall portion 22 of the positive electrode can 20, the gasket is applied. Since the upper portion 31a is not in contact with the flat portion of the positive electrode can 20, the force from the lower portion of the gasket can be released by a slight deformation of the upper portion of the gasket 31a. That is, by providing a slight space between the gasket upper portion 31 a and the flat portion of the positive electrode can 20, it is possible to prevent peeling of the gasket upper portion 31 a due to interference between the gasket upper portion 31 a and the flat portion of the positive electrode can 20.

図６に示すように、ガスケット下部３１ｂは、その内面が、ガスケット上部３１ａの内面よりも正極缶２０の径方向外方に位置するように形成されている。すなわち、ガスケット下部３１ｂのガスケット上部側には、該ガスケット下部３１ｂの内面の径よりもガスケット上部３１ａの内面の径が大きくなるように内面段差部３１ｃ（段差部）が形成されている。この内面段差部３１ｃは、ガスケット上部３１ａからガスケット下部３１ｂに向かって徐々に内径が大きくなるテーパ状に形成されている。また、内面段差部３１ｃは、正極缶２０の周壁部２２の段部２２ｃと拡径部２２ｂの開口端との間に位置するように形成されている。これにより、図６に示すように、ガスケット下部３１ｂにおいて、段部２２ｃの正極缶内方側に位置する部分の厚み（図６中のＢ）よりも、拡径部２２ｂの正極缶内方側に位置する部分の厚み（図６中のＡ）の方が小さくなっている。   As shown in FIG. 6, the gasket lower portion 31 b is formed so that the inner surface thereof is positioned radially outward of the positive electrode can 20 from the inner surface of the gasket upper portion 31 a. That is, an inner surface step portion 31c (step portion) is formed on the gasket upper portion side of the gasket lower portion 31b so that the diameter of the inner surface of the gasket upper portion 31a is larger than the diameter of the inner surface of the gasket lower portion 31b. The inner surface step portion 31c is formed in a taper shape whose inner diameter gradually increases from the gasket upper portion 31a toward the gasket lower portion 31b. Further, the inner surface step portion 31 c is formed so as to be positioned between the step portion 22 c of the peripheral wall portion 22 of the positive electrode can 20 and the opening end of the enlarged diameter portion 22 b. Thereby, as shown in FIG. 6, in the gasket lower part 31b, the positive electrode can inner side of the enlarged diameter part 22b is larger than the thickness (B in FIG. 6) of the portion located on the inner side of the positive electrode can of the step part 22c. The thickness of the portion located at (A in FIG. 6) is smaller.

このような構成にすることで、扁平形電池２を製造する際、正極缶１０の周壁部１２の開口端部を正極缶２０の段部２２ｃにかしめたときに、そのかしめによって生じる圧縮力をガスケット下部３１ｂで吸収することができる。すなわち、負極缶１０を正極缶２０にかしめた際に、該正極缶２０の段部２２ｃに圧縮力が作用すると、該段部２２ｃを介してガスケット下部３１ｂにも圧縮力が作用する。このとき、該ガスケット下部３１ｂでは、段部２２ｃの正極缶内方側に位置する部分（この実施形態では内面段差部３１ｃ）よりも肉厚が小さい部分、すなわち拡径部２２ｂの正極缶内方側に位置する部分が変形する。これにより、負極缶１０と正極缶２０との嵌合の際にガスケット下部３１ｂに作用する力を、該ガスケット下部３１ｂで吸収できる。   With this configuration, when the flat battery 2 is manufactured, when the open end of the peripheral wall portion 12 of the positive electrode can 10 is caulked to the step portion 22c of the positive electrode can 20, the compressive force generated by the caulking is generated. It can be absorbed by the gasket lower part 31b. That is, when the negative electrode can 10 is caulked to the positive electrode can 20, if a compressive force is applied to the step portion 22c of the positive electrode can 20, the compressive force is also applied to the gasket lower portion 31b via the step portion 22c. At this time, in the gasket lower portion 31b, a portion having a smaller thickness than a portion (in this embodiment, the inner surface step portion 31c) located on the inner side of the step portion 22c, that is, the inside of the positive electrode can of the enlarged diameter portion 22b. The part located on the side is deformed. Thereby, the force which acts on the gasket lower part 31b when the negative electrode can 10 and the positive electrode can 20 are fitted can be absorbed by the gasket lower part 31b.

また、拡径部２２ｂの正極缶内方側に位置する部分の厚み（図６中のＡ）を小さくすることで、圧縮力を負極缶１０の底のＲ部（底端部）付近に集中させることができ、扁平形電池２を効率よく確実に密封することができる。   Further, the compressive force is concentrated in the vicinity of the R portion (bottom end) of the bottom of the negative electrode can 10 by reducing the thickness (A in FIG. 6) of the portion located on the inner side of the positive electrode can of the enlarged diameter portion 22b. The flat battery 2 can be sealed efficiently and reliably.

（実施形態３）
図７は本発明の第３の実施の形態における正極缶２０とガスケット３０を示す。本実施の形態における扁平形電池は、正極缶２０、負極缶１０及びガスケット３０の形状は実施の形態１と同様である。また、電極体は実施の形態２における積層構造の電極体と同様であるため詳細の説明は省略する。 (Embodiment 3)
FIG. 7 shows a positive electrode can 20 and a gasket 30 according to the third embodiment of the present invention. In the flat battery in the present embodiment, the shapes of the positive electrode can 20, the negative electrode can 10, and the gasket 30 are the same as those in the first embodiment. Further, since the electrode body is the same as the electrode body having the laminated structure in the second embodiment, detailed description thereof is omitted.

本実施の形態においては、電極には複数の電極を交互に積層した積層構造の電極体を使用するため、電池の上部にも負極が存在し、負極と正極缶との接触が生じる可能性がある。本実施形態では、図７に示すように、正極缶２０の周壁部２２の内面の段部２２ｃの下面から拡径部２２ｂにかけてガスケット３０が設けられている。このガスケット３０に加えて、周壁部２２の基端部２２ａの内面には絶縁コート７１が配置される。絶縁コート７１は、例えばブチル系ゴムをトルエン又はキシレンに溶かしたものを塗布し乾燥させることにより形成される。これにより、電極体４０（負極リード５２）と正極缶２０との短絡が防止される。   In the present embodiment, since an electrode body having a laminated structure in which a plurality of electrodes are alternately stacked is used as the electrode, there is a possibility that a negative electrode also exists on the upper part of the battery, and contact between the negative electrode and the positive electrode can occurs. is there. In the present embodiment, as shown in FIG. 7, a gasket 30 is provided from the lower surface of the step portion 22 c on the inner surface of the peripheral wall portion 22 of the positive electrode can 20 to the enlarged diameter portion 22 b. In addition to the gasket 30, an insulating coat 71 is disposed on the inner surface of the base end portion 22 a of the peripheral wall portion 22. The insulating coat 71 is formed, for example, by applying a butyl rubber dissolved in toluene or xylene and drying it. Thereby, the short circuit with the electrode body 40 (negative electrode lead 52) and the positive electrode can 20 is prevented.

本発明の各実施形態では、負極缶１０を外装缶としていて、正極缶２０を封口缶としているが、逆に負極缶が封口缶で、正極缶が外装缶であってもよい。   In each embodiment of the present invention, the negative electrode can 10 is an outer can and the positive electrode can 20 is a sealed can. Conversely, the negative electrode can may be a sealed can and the positive electrode can may be an outer can.

また、本発明の各実施形態では、負極缶１０及び正極缶２０を、それぞれ有底円筒状に形成して、扁平形電池１をコイン状に形成したが、この限りではなく、扁平形電池を、多角柱状など、円柱状以外の形状に形成してもよい。   Further, in each embodiment of the present invention, the negative electrode can 10 and the positive electrode can 20 are each formed in a bottomed cylindrical shape, and the flat battery 1 is formed in a coin shape. Alternatively, it may be formed in a shape other than the columnar shape such as a polygonal columnar shape.

また、本発明の各実施形態では、封口缶としての正極缶にステンレスを用いているが、この限りではなく、板状のアルミニウムと板状のステンレスとを重ねて結合してなるクラッド材を用いてもよい。しかも、正極缶は、周壁部が負極缶の周壁部に覆われるため、該正極缶の内面側に位置するアルミニウムが露出して腐食するのを防止できる。   Further, in each embodiment of the present invention, stainless steel is used for the positive electrode can as a sealing can. However, the present invention is not limited to this, and a clad material formed by stacking and bonding plate-like aluminum and plate-like stainless steel is used. May be. Moreover, since the peripheral wall portion of the positive electrode can is covered with the peripheral wall portion of the negative electrode can, the aluminum located on the inner surface side of the positive electrode can can be prevented from being exposed and corroded.

１ 扁平形電池
２ 扁平形電池
１０ 負極缶（外装缶）
１１ 底部
１２ 周壁部（側壁部）
２０ 正極缶（封口缶）
２１ 平面部（上面部）
２２ 周壁部（側面部）
２２ａ 基端部
２２ｂ 拡径部
２２ｃ 段部
２３ Ｒ部
３０ ガスケット
３１ ガスケット内側部
３１ａ ガスケット上部
３１ｂ ガスケット下部
３１ｃ 内面段差部（段差部）
３２ ガスケット外側部
３３ ガスケット先端部
４０ 電極体
４１ 正極
４６ 負極 DESCRIPTION OF SYMBOLS 1 Flat battery 2 Flat battery 10 Negative electrode can (exterior can)
11 bottom 12 peripheral wall (side wall)
20 Positive electrode can (sealed can)
21 Flat surface (upper surface)
22 Perimeter wall (side)
22a Base end portion 22b Expanded diameter portion 22c Step portion 23 R portion 30 Gasket 31 Gasket inner portion 31a Gasket upper portion 31b Gasket lower portion 31c Inner surface step portion (step portion)
32 Gasket outer portion 33 Gasket tip portion 40 Electrode body 41 Positive electrode 46 Negative electrode

Claims (12)

上面部と、段状に広がる段部を備えた側面部とを有する封口缶と、
前記封口缶よりも外径が大きく、底部と側壁部とを有する外装缶と、
前記封口缶の側面部を挟み込むようにモールド形成されるガスケットと、
正極、負極及びセパレータを備える電極体と、を備えた扁平形電池であって、
前記電極体は、前記封口缶の側面部に対し前記外装缶の側壁部を前記ガスケットを挟んでかしめることにより密閉される空間に配置され、
前記段部の下方における前記ガスケットの前記封口缶の側面部内側の厚みは、前記外装缶の底部における前記封口缶の側面部内側の面から前記電極体方向への厚みよりも大きく形成され、前記ガスケットは前記封口缶の上面部から分離されて形成されることを特徴とする扁平形電池。 A sealing can having an upper surface portion and a side surface portion including a stepped portion that spreads out in a stepped manner;
An outer can having a larger outer diameter than the sealed can, and having a bottom and a side wall; and
A gasket that is molded so as to sandwich the side surface of the sealing can;
A flat battery including a positive electrode, a negative electrode, and an electrode body including a separator,
The electrode body is disposed in a space that is sealed by caulking the side wall portion of the outer can with the gasket sandwiched between the side surface portion of the sealing can,
The thickness of the inner side surface of the sealing can of the gasket below the stepped portion is formed to be larger than the thickness in the electrode body direction from the inner surface of the side surface of the sealing can at the bottom of the outer can. The flat battery is characterized in that the gasket is formed separately from the upper surface of the sealing can. 前記側面部において前記上面部から前記段部に至るまでの領域である側面部上部の内側にはガスケットが形成されておらず、前記段部から前記底部に至るまでの領域である側面部下部の内側には前記ガスケットが形成されており、前記側面部上部の内側の表面と、前記側面部下部に形成されたガスケットの表面は連続した面を形成することを特徴とする請求項１に記載の扁平形電池。 No gasket is formed on the inner side of the upper part of the side part, which is an area from the upper surface part to the step part in the side part, and a lower part of the side part which is an area from the step part to the bottom part. The said gasket is formed inside, The surface of the inner side of the said side part upper part and the surface of the gasket formed in the said side part lower part form a continuous surface, The Claim 1 characterized by the above-mentioned. Flat battery. 前記側面部上部の内側の表面と、前記側面部下部に形成されたガスケットの表面はテーパ状の面を形成することを特徴とする請求項２に記載の扁平形電池。 The flat battery according to claim 2, wherein the inner surface of the upper portion of the side surface portion and the surface of the gasket formed at the lower portion of the side surface portion form a tapered surface. 前記電極体は、１組の正極、負極及びセパレータから構成される単層構造であり、前記正極は前記上面部に接しており、前記セパレータは、前記底部に接する負極を覆うように配置されることを特徴とする請求項１に記載の扁平形電池。 The electrode body has a single-layer structure including a pair of a positive electrode, a negative electrode, and a separator, the positive electrode is in contact with the upper surface portion, and the separator is disposed so as to cover the negative electrode in contact with the bottom portion. The flat battery according to claim 1. 前記側面部上部には内側に絶縁コートが形成されることを特徴とする請求項２に記載の扁平形電池。 The flat battery according to claim 2, wherein an insulating coat is formed on an inner side of the upper part of the side part. 前記側面部において前記上面部から前記段部に至るまでの領域である側面部上部の内側の一部と前記段部から前記底部に至るまでの領域である側面部下部の内側には前記ガスケットが形成されており、前記上面部と前記ガスケットの前記上面側の端部との間は空間により分離されることを特徴とする請求項１に記載の扁平形電池。 In the side surface portion, the gasket is provided on a part of the inside of the upper portion of the side surface portion that is a region from the upper surface portion to the step portion and on the inner side of the lower portion of the side surface portion that is a region from the step portion to the bottom portion. The flat battery according to claim 1, wherein the flat battery is formed and is separated by a space between the upper surface portion and an end portion of the gasket on the upper surface side. 前記電極体は、複数の組の正極、負極及びセパレータから構成される積層構造であり、複数の正極及び複数の負極から引き出されたリードはそれぞれ正極缶及び負極缶に接続されることを特徴とする請求項５または６に記載の扁平形電池。 The electrode body has a laminated structure including a plurality of sets of positive electrodes, negative electrodes, and separators, and leads drawn from the plurality of positive electrodes and the plurality of negative electrodes are respectively connected to the positive electrode can and the negative electrode can. The flat battery according to claim 5 or 6. 上面部と、段状に広がる段部を備えた側面部とを有する封口缶と、
前記封口缶よりも外径が大きく、底部と側壁部とを有する外装缶と、
前記封口缶の側面部を挟み込むようにモールド形成されるガスケットと、
正極、負極及びセパレータを備える電極体と、を備えた扁平形電池であって、
前記電極体は、前記封口缶の側面部に対し前記外装缶の側壁部を前記ガスケットを挟んでかしめることにより密閉される空間に配置され、
前記側面部において前記上面部から前記段部に至るまでの領域である側面部上部の内側にはガスケットが形成されておらず、前記段部から前記底部に至るまでの領域である側面部下部の内側には前記ガスケットが形成されており、前記側面部上部の内側の表面と、前記側面部下部に形成されたガスケットの表面は連続したテーパ状の面を形成することを特徴とする扁平形電池。 A sealing can having an upper surface portion and a side surface portion including a stepped portion that spreads out in a stepped manner;
An outer can having a larger outer diameter than the sealed can, and having a bottom and a side wall; and
A gasket that is molded so as to sandwich the side surface of the sealing can;
A flat battery including a positive electrode, a negative electrode, and an electrode body including a separator,
The electrode body is disposed in a space that is sealed by caulking the side wall portion of the outer can with the gasket sandwiched between the side surface portion of the sealing can,
No gasket is formed on the inner side of the upper part of the side part, which is an area from the upper surface part to the step part in the side part, and a lower part of the side part which is an area from the step part to the bottom part. A flat battery characterized in that the gasket is formed on the inner side, and the inner surface of the upper portion of the side surface portion and the surface of the gasket formed at the lower portion of the side surface portion form a continuous tapered surface. . 前記電極体は、１組の正極、負極及びセパレータから構成される単層構造であり、前記正極は前記上面部に接しており、前記セパレータは、前記底部に接する負極を覆うように配置されることを特徴とする請求項８に記載の扁平形電池。 The electrode body has a single-layer structure including a pair of a positive electrode, a negative electrode, and a separator, the positive electrode is in contact with the upper surface portion, and the separator is disposed so as to cover the negative electrode in contact with the bottom portion. The flat battery according to claim 8. 前記側面部上部には内側に絶縁コートが形成されることを特徴とする請求項９に記載の扁平形電池。 The flat battery according to claim 9, wherein an insulating coat is formed on an inner side of the upper part of the side part. 上面部と、段状に広がる段部を備えた側面部とを有する封口缶と、
前記封口缶の側面部を挟み込むようにモールド形成されるガスケットと、を備える扁平形電池の封口缶であって、
前記段部の下方における前記ガスケットの前記封口缶の側面部内側の厚みは、前記外装缶の底部における前記封口缶の側面部内側の面から前記電極体方向への厚みよりも大きく形成され、前記ガスケットは前記封口缶の上面部から分離されて形成されることを特徴とする扁平形電池の封口缶。 A sealing can having an upper surface portion and a side surface portion including a stepped portion that spreads out in a stepped manner;
A flat battery sealing can comprising a gasket formed so as to sandwich a side surface portion of the sealing can,
The thickness of the inner side surface of the sealing can of the gasket below the stepped portion is formed to be larger than the thickness in the electrode body direction from the inner surface of the side surface of the sealing can at the bottom of the outer can. The flat battery sealing can is characterized in that the gasket is formed separately from the upper surface of the sealing can. 上面部と、段状に広がる段部を備えた側面部とを有する封口缶と、
前記封口缶の側面部を挟み込むようにモールド形成されるガスケットと、を備える扁平形電池の封口缶であって、
前記側面部において前記上面部から前記段部に至るまでの領域である側面部上部の内側にはガスケットが形成されておらず、前記段部から前記底部に至るまでの領域である側面部下部の内側には前記ガスケットが形成されており、前記側面部上部の内側の表面と、前記側面部下部に形成されたガスケットの表面は連続したテーパ状の面を形成することを特徴とする扁平形電池の封口缶。 A sealing can having an upper surface portion and a side surface portion including a stepped portion that spreads out in a stepped manner;
A flat battery sealing can comprising a gasket formed so as to sandwich a side surface portion of the sealing can,
No gasket is formed on the inner side of the upper part of the side part, which is an area from the upper surface part to the step part in the side part, and a lower part of the side part which is an area from the step part to the bottom part. A flat battery characterized in that the gasket is formed on the inner side, and the inner surface of the upper portion of the side surface portion and the surface of the gasket formed at the lower portion of the side surface portion form a continuous tapered surface. Sealing can.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111564590A (en) * 2020-05-12 2020-08-21 路华置富电子(深圳)有限公司 Battery with explosion-proof structure
US11075420B2 (en) 2016-12-27 2021-07-27 Maxell Holdings, Ltd. Coin-type battery and manufacturing method thereof

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6248661U (en) * 1985-09-13 1987-03-25
JPH0434837A (en) * 1990-05-30 1992-02-05 Matsushita Electric Ind Co Ltd Enclosed battery
JPH04341756A (en) * 1991-05-16 1992-11-27 Matsushita Electric Ind Co Ltd Manufacture of closed battery
JPH09129198A (en) * 1995-10-31 1997-05-16 Matsushita Electric Ind Co Ltd Flat organic electrolyte battery
JP2002056827A (en) * 2000-08-09 2002-02-22 Seiko Instruments Inc Nonaqueous electrolyte secondary battery
JP2011187341A (en) * 2010-03-09 2011-09-22 Hitachi Maxell Energy Ltd Flat battery
WO2012124187A1 (en) * 2011-03-14 2012-09-20 日立マクセルエナジー株式会社 Flat battery

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6248661U (en) * 1985-09-13 1987-03-25
JPH0434837A (en) * 1990-05-30 1992-02-05 Matsushita Electric Ind Co Ltd Enclosed battery
JPH04341756A (en) * 1991-05-16 1992-11-27 Matsushita Electric Ind Co Ltd Manufacture of closed battery
JPH09129198A (en) * 1995-10-31 1997-05-16 Matsushita Electric Ind Co Ltd Flat organic electrolyte battery
JP2002056827A (en) * 2000-08-09 2002-02-22 Seiko Instruments Inc Nonaqueous electrolyte secondary battery
JP2011187341A (en) * 2010-03-09 2011-09-22 Hitachi Maxell Energy Ltd Flat battery
WO2012124187A1 (en) * 2011-03-14 2012-09-20 日立マクセルエナジー株式会社 Flat battery

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11075420B2 (en) 2016-12-27 2021-07-27 Maxell Holdings, Ltd. Coin-type battery and manufacturing method thereof
CN111564590A (en) * 2020-05-12 2020-08-21 路华置富电子(深圳)有限公司 Battery with explosion-proof structure
CN111564590B (en) * 2020-05-12 2022-11-18 路华置富电子(深圳)有限公司 Battery with explosion-proof structure

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