JP2003249198A

JP2003249198A - Battery cell

Info

Publication number: JP2003249198A
Application number: JP2002046115A
Authority: JP
Inventors: Isato Higuchi; 勇人樋口; Toshiya Takaishi; 季也高石
Original assignee: Hitachi Maxell Ltd
Current assignee: Maxell Holdings Ltd
Priority date: 2002-02-22
Filing date: 2002-02-22
Publication date: 2003-09-05

Abstract

<P>PROBLEM TO BE SOLVED: To provide a volume-efficient battery cell having shape flexibility, being easy to contact conductively with a cell mounting device without volume loss over terminal portions. <P>SOLUTION: A battery cell case 2 is formed by employing a pair of packaging materials 3, 4 each having at least one metal layer 3a, 4a, on one side thereof, and joining the periphery parts of the opposite sides thereof via heat- fusible resins 3b, 4b. The metal layers 3a, 4a are insulated from each other in the heat-fused part M of the packaging materials 3 and 4. Then the metal layer 4a of the packaging material 4 is electrically coupled to a positive electrode 6 so that the potential of the layer 4a is equal to that of the positive electrode, and the metal layer 3a of the packaging material 3 is electrically coupled to a negative electrode 7 so that the potential of the layer 3a is equal to that of the electrode 7. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

【０００１】[0001]

【発明の属する技術分野】本発明は、金属層を有する一
対の外装材によって電池ケースが構成された電池に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery in which a battery case is composed of a pair of exterior materials having a metal layer.

【０００２】[0002]

【従来の技術、および発明が解決しようとする課題】携
帯電話や携帯情報端末あるいはノートブックパソコン等
の携帯用ないし小型の電子機器に搭載される電池におい
ては、当該機器への電気的接続すなわち導通接触が容易
であることが望ましい。2. Description of the Related Art In a battery mounted in a portable or small electronic device such as a mobile phone, a personal digital assistant, or a notebook personal computer, electrical connection or conduction to the device is required. Easy contact is desirable.

【０００３】この点につき、従来のコイン型電池あるい
はボタン型電池では、例えば特開平１１−６７２８２号
公報に示されているように、電池ケースを構成している
金属缶を一方の電極端子として使用し、その開口部を封
止するために金属缶の開口部に環状ガスケット（絶縁
体）を介して装着された金属製の封口板を他方の電極端
子として使用していることから、機器への電気的接続は
比較的容易である。また、筒型（または角型）リウチム
イオン電池等では、電池ケースに金属缶が使用されるた
め、これを一方の電極端子として使用している。With respect to this point, in the conventional coin-type battery or button-type battery, for example, as disclosed in Japanese Patent Application Laid-Open No. 11-67282, a metal can forming a battery case is used as one electrode terminal. In order to seal the opening, a metal sealing plate attached to the opening of the metal can via an annular gasket (insulator) is used as the other electrode terminal. Electrical connection is relatively easy. Further, in a tubular (or rectangular) lithium ion battery or the like, a metal can is used for the battery case, and therefore this is used as one electrode terminal.

【０００４】しかしながら、これらの金属缶電池は、電
池ケースを構成する金属缶が成型品（いわゆる型もの）
であるため、サイズや薄さ等を自由に変更できない、つ
まり形状の自由度あるいはデザインの自由度（以下、形
状自由度という）に乏しいという難点がある。言うまで
もなく、小型電子機器には様々なデザインのものがあ
り、その電池装着部の形状にも種々のバリエーションが
あることや、特に近年における小型化・薄型化の要請の
高まりを考えると、これらに柔軟に対応しうるような形
状自由度を有していることが望ましい。ところが、先に
述べたような金属缶電池にあっては、電池ケースが型も
のであるため、少量多品種の用途にはコスト的に不向き
であり、上記のような形状自由度の要求に応え難い。However, in these metal can batteries, the metal cans forming the battery case are molded products (so-called molds).
Therefore, there is a drawback that the size, thinness, etc. cannot be freely changed, that is, the degree of freedom in shape or the degree of freedom in design (hereinafter referred to as the degree of freedom in shape) is poor. Needless to say, there are various designs of small electronic devices, and there are various variations in the shape of the battery mounting part, and considering the increasing demand for miniaturization and thinning in recent years, these are It is desirable to have a degree of freedom in shape that allows flexible handling. However, in the metal can battery as described above, since the battery case is of a mold type, it is not suitable for a small quantity and a wide variety of applications in terms of cost. hard.

【０００５】一方、最近では、電池ケースを構成する外
装材として、ラミネートフィルム、すなわち金属層（ア
ルミニウム箔等の金属箔もしくは金属薄板）の外面側に
保護層としての樹脂層を設け、かつ内面側に熱融着可能
な樹脂層を設けたフィルムを使用することも行われてい
る（以下、このようなラミネートフィルムを使用した電
池を「ラミネートフィルム電池」という）。これによれ
ば、熱融着を利用してラミネートフィルムの所定部分ど
うしを貼り合わせて封止することによって電池ケースを
形成できるため、機器の形状に合わせた電池を比較的容
易に製造できる。On the other hand, recently, a resin film as a protective layer is provided on the outer surface side of a laminate film, that is, a metal layer (a metal foil such as an aluminum foil or a thin metal plate) as an exterior material constituting a battery case, and the inner surface side thereof is provided. A film provided with a heat-sealable resin layer is also used (hereinafter, a battery using such a laminated film is referred to as a "laminated film battery"). According to this, since the battery case can be formed by bonding and sealing the predetermined portions of the laminate film by utilizing heat fusion, a battery adapted to the shape of the device can be relatively easily manufactured.

【０００６】しかしながら、ラミネートフィルム電池に
おいては、外装材であるラミネートフィルムの外面全体
に保護絶縁層としての樹脂層が存在する。言い換えれ
ば、ラミネートフィルム中の金属層の外面側全部が外面
樹脂フィルムによって覆われた状態となっている。その
ため、金属缶電池では可能であった外装材への導通接触
による電気の取り出しができず、電池内の電極端子群を
そのまま外部に取り出す構造が採用されているが、この
ような構造では、配線の取り回し等で体積が多く必要に
なる。この体積の増加は、小型電子機器や、電池占有体
積を極力小さくしなければならない小型電子機器等にと
って大きなロスとなる。However, in the laminated film battery, a resin layer as a protective insulating layer exists on the entire outer surface of the laminated film which is the exterior material. In other words, the outer surface side of the metal layer in the laminate film is entirely covered with the outer surface resin film. Therefore, it is not possible to take out electricity by conducting contact with the outer packaging material, which was possible with a metal can battery, and a structure is adopted in which the electrode terminal group inside the battery is taken out as it is. A large volume is required due to the handling of. This increase in volume causes a large loss for small electronic devices, small electronic devices for which the occupied volume of the battery must be minimized, and the like.

【０００７】なお、特開２０００−３５３４９６号公報
では、外装材にラミネートフィルムを用いた電池におい
て、電池容器内面に一方の電極（正極または負極）との
接触部を有し、この接触部におけるラミネートフィルム
中の金属層から電池容器内面までの樹脂層が電気伝導性
を有する構造とすることが提案されている。これは、ラ
ミネートフィルム電池を高周波回路と共に用いた場合に
高周波回路の動作が不安定となることを防止するためで
あるが、このような構造とすれば、ラミネートフィルム
電池においても、外装材を構成している金属層の電位を
一方の電極（正極または負極）の電位と等電位とするこ
とができる。しかし、この場合においても、電池容器外
面には樹脂層（ラミネートフィルムを構成している表層
樹脂層）が存在し、この樹脂層によって金属層の外表面
全体が被覆されているから、先に述べた一般的なラミネ
ートフィルム電池の場合と同様、そのままでは外装材へ
の導通接触による電気の取り出しはできない。また、ラ
ミネートフィルム中の金属層全体が正極または負極の一
方と同一電位となるに過ぎないから、何らかの方法で金
属層を一方の電極端子として利用できるようにしたとし
ても、他方の電極については電池内から電極端子（電極
リード）を外部に取り出さざるを得ない。したがって、
この種の端子の引き回しによる体積ロスは避けられな
い。In Japanese Patent Laid-Open No. 2000-353496, a battery using a laminate film as an exterior material has a contact portion with one electrode (positive electrode or negative electrode) on the inner surface of the battery container, and the laminate at this contact portion is provided. It has been proposed that the resin layer from the metal layer in the film to the inner surface of the battery container has electrical conductivity. This is to prevent the operation of the high frequency circuit from becoming unstable when the laminate film battery is used together with the high frequency circuit. With such a structure, the outer packaging material can be configured even in the laminate film battery. The potential of the metal layer being formed can be made equal to the potential of one electrode (positive electrode or negative electrode). However, even in this case, a resin layer (surface resin layer forming a laminate film) is present on the outer surface of the battery container, and the resin layer covers the entire outer surface of the metal layer. As in the case of a general laminated film battery, electricity cannot be taken out as it is by conducting contact with the exterior material. Further, since the entire metal layer in the laminate film has only the same potential as one of the positive electrode and the negative electrode, even if the metal layer is made available as one of the electrode terminals by some method, the other electrode is a battery. There is no choice but to take out the electrode terminals (electrode leads) from the inside. Therefore,
Volume loss due to this type of terminal routing is unavoidable.

【０００８】本発明は、上記のような問題を解消するも
ので、形状自由度が高く、しかも搭載機器との導通接触
が容易で、端子部による容積ロスを生じない体積効率の
高い電池を提供することを目的とする。換言すれば、本
発明は、ラミネートフィルム電池のもつメリット（形状
自由度）と、コイン型電池あるいはボタン型電池のもつ
メリット（搭載機器との導通接触の容易性、高体積効
率）の双方を併せ持った電池を提供するものである。The present invention solves the above problems and provides a battery having a high degree of freedom in shape, easy conductive contact with mounted equipment, and high volume efficiency without causing volume loss due to terminals. The purpose is to do. In other words, the present invention has both the advantages of the laminated film battery (the degree of freedom of shape) and the advantages of the coin type battery or the button type battery (ease of conductive contact with the mounted device and high volume efficiency). To provide a battery.

【０００９】[0009]

【課題を解決するための手段】本発明は、電池ケース内
に、正極および負極を含む発電要素を収容してなる電池
において、次のように構成したことを特徴とする。The present invention is characterized in that a battery having a power generation element including a positive electrode and a negative electrode housed in a battery case is configured as follows.

【００１０】すなわち、電池ケースを一対の外装材で構
成する。その場合に、一対の外装材として、それぞれ、
一方の面（発電要素を収容していない外面）に一部また
は全部の金属面が露出した少なくとも一層の金属層を有
する外装材を使用し、これらの外装材のそれぞれ他方の
面における周辺部どうしを、熱融着樹脂を介して接合す
ることにより、両外装材間に前記発電要素を収容するセ
ル室を形成した構成とする。そして、両外装材のうちの
一方の外装材における金属層が正極電位と等電位となる
ように当該金属層を正極に電気的に接続するとともに、
他方の外装材における金属層が負極電位と等電位となる
ように当該金属層を負極に電気的に接続し、かつ両外装
材の熱融着接合部において一方の外装材の金属層と他方
の外装材の金属層とを電気的に絶縁した構成とする。That is, the battery case is composed of a pair of exterior materials. In that case, as a pair of exterior materials,
An exterior material having at least one metal layer in which a part or all of the metal surface is exposed is used on one surface (an outer surface not accommodating the power generation element), and the peripheral portions on the other surface of each of the exterior materials are used. Is bonded via a heat-sealing resin to form a cell chamber that accommodates the power generation element between both exterior materials. Then, the metal layer in one of the two exterior materials is electrically connected to the positive electrode so that the metal layer has the same potential as the positive electrode potential,
The metal layer of the other packaging material is electrically connected to the negative electrode so that the metal layer has the same potential as the negative electrode potential, and the metal layer of the one packaging material and the other of the other packaging material in the heat-sealing joint portion of the two packaging materials. The metal layer of the exterior material is electrically insulated.

【００１１】[0011]

【作用】上記の構成によれば、一対の外装材を熱融着樹
脂を介して接合する、つまり熱融着接合することによっ
て電池ケースが形成されるので、ラミネートフィルム電
池の場合のように機器の形状に合わせた電池形状とする
ことが比較的容易である。すなわち、上記構成により形
状自由度の高い電池を実現できる。According to the above construction, since the battery case is formed by joining the pair of outer packaging materials via the heat-sealing resin, that is, the heat-sealing is performed, the device can be formed as in the case of the laminated film battery. It is relatively easy to make a battery shape that matches the shape of. That is, a battery having a high degree of freedom in shape can be realized with the above configuration.

【００１２】しかも、本発明の電池においては、一対の
外装材における熱融着接合部側とは反対側の面、つまり
一方の外装材における金属層の表面（金属面）および他
方の外装材における金属層の表面（金属面）が、それぞ
れ、電池ケースにおける一方の外面側およびその反対面
側に位置する他方の外面側となって、両金属面の一部ま
たは全部がそれぞれ外部に露出した状態となる。そし
て、この状態で、両金属層が熱融着接合部で互いに絶縁
されたうえで、一方の金属層および他方の金属層が、そ
れぞれ、正極および負極と等電位となる。したがって、
これらの金属層の外部露出部分（金属面の一部または全
部）を正極端子および負極端子として使用することがで
き、これらの金属層の外部露出部分、すなわち前記電池
ケースにおける一方の外面および他方の外面に、もしく
はこれらの所定部分に、機器側の所定部分を直接接触さ
せるだけで、電池からの電気エネルギーの取り出しが可
能となる。また、前記電池ケースの外面を形成している
一方および他方の金属層がそれぞれ正極端子および負極
端子となるので、電池内の電極端子群を外部に引き出す
必要がない。したがって、電極リードの引き回しによる
体積ロスを大幅に減少させることができ、その分だけ体
積効率の良い電池が得られる。Moreover, in the battery of the present invention, the surfaces of the pair of exterior materials opposite to the heat-sealing joint side, that is, the surface (metal surface) of the metal layer in one exterior material and the other exterior material A state in which the surface (metal surface) of the metal layer is one outer surface side of the battery case and the other outer surface side located on the opposite surface side of the battery case, respectively, and a part or all of both metal surfaces are exposed to the outside. Becomes Then, in this state, both metal layers are insulated from each other at the heat-sealing joint, and one metal layer and the other metal layer become equipotential with the positive electrode and the negative electrode, respectively. Therefore,
The externally exposed portions (a part or all of the metal surface) of these metal layers can be used as the positive electrode terminal and the negative electrode terminal, and the externally exposed portions of these metal layers, that is, one outer surface and the other in the battery case can be used. The electrical energy can be taken out from the battery only by directly contacting a predetermined portion on the device side with the outer surface or these predetermined portions. Further, since the one and the other metal layers forming the outer surface of the battery case serve as the positive electrode terminal and the negative electrode terminal, respectively, it is not necessary to draw out the electrode terminal group in the battery to the outside. Therefore, the volume loss due to the routing of the electrode leads can be significantly reduced, and a battery with good volume efficiency can be obtained accordingly.

【００１３】[0013]

【発明の実施の形態】本発明は、集電体を用いる電池お
よび集電体を用いない電池のいずれにも適用することが
できる。集電体を用いる場合は、正極集電体の片面もし
くは両面に正極活物質層を形成して正極とし、負極集電
体の片面もしくは両面に負極活物質層を形成して負極と
する。その場合、正極集電体および負極集電の材質は、
特に限定されるものではないが、例えば、正極集電体に
ついてはアルミニウム、アルミニウム合金等を使用する
ことができ、負極集電体についてはニッケル、銅、鉄、
ステンレス鋼、またはこれらを組み合わてなる合金等を
使用することができる。BEST MODE FOR CARRYING OUT THE INVENTION The present invention can be applied to both a battery using a current collector and a battery not using a current collector. When a current collector is used, a positive electrode active material layer is formed on one or both sides of a positive electrode current collector to form a positive electrode, and a negative electrode active material layer is formed on one or both sides of a negative electrode current collector to form a negative electrode. In that case, the materials of the positive electrode current collector and the negative electrode current collector are
Although not particularly limited, for example, aluminum, an aluminum alloy or the like can be used for the positive electrode current collector, and nickel, copper, iron, or the like for the negative electrode current collector.
It is possible to use stainless steel, an alloy obtained by combining these, or the like.

【００１４】本発明における電池ケースは一対の外装材
によって構成されるが、この場合の一方の外装材におけ
る金属層と、他方の外装材における金属層は、いずれか
一方が正極と等電位とされ、他方が負極と等電位とされ
るから、両者は互いに異種の金属で構成されているのが
好ましい。すなわち、両金属層には、それぞれの極に適
した互いに異種の金属を使用するのが好ましい。その場
合、集電体とこれと等電位となる金属層は、材質が異な
っていてもよいが、いわゆる局部電池の形成を回避する
という意味で同じ材質が望ましい。The battery case according to the present invention is composed of a pair of exterior materials. In this case, one of the metal layers in the one exterior material and the metal layer in the other exterior material has the same potential as the positive electrode. Since the other has the same potential as the negative electrode, it is preferable that both are made of different metals. That is, it is preferable to use different metals suitable for each pole in both metal layers. In that case, the current collector and the metal layer having the same electric potential as that of the current collector may be made of different materials, but the same material is desirable in the sense of avoiding formation of a so-called local battery.

【００１５】熱融着樹脂としては、ポリプロピレン、ポ
リエチレン等のポリオレフィン樹脂、ポリエステル系樹
脂、ポリビニリデン系樹脂、ポリアミド系樹脂、フッ素
系樹脂、エチレンビニルアセテート樹脂、アイオノマー
樹脂等を使用することができる。Polyolefin resin such as polypropylene and polyethylene, polyester resin, polyvinylidene resin, polyamide resin, fluorine resin, ethylene vinyl acetate resin, ionomer resin and the like can be used as the heat-sealing resin.

【００１６】本発明における電池ケースは、一対の外装
材が熱融着樹脂を介して接合されることにより形成され
るが、このようにして形成された電池ケースでは、熱融
着樹脂により接合された部分（熱融着接合部）が、前記
の両金属層を互いに電気的に絶縁する機能を果たす、す
なわち絶縁層となる。ただし、熱融着接合部を形成して
いる熱融着樹脂層の厚さが薄い場合には絶縁不良となる
ことも考えられる。そこで、熱融着接合部の絶縁層とし
ての機能をより確実なものとして上記ような絶縁不良が
生じるのを防止するために、当該熱融着接合部に、前記
熱融着樹脂より高い融点を有する絶縁体、または前記熱
融着樹脂の熱融着温度においても形状を保持しうる絶縁
体を介装してもよい。The battery case according to the present invention is formed by joining a pair of exterior materials via a heat-sealing resin. In the battery case thus formed, the heat-sealing resin is used for joining. The portion (heat-bonding joint) serves to electrically insulate the two metal layers from each other, that is, serves as an insulating layer. However, if the thickness of the heat-sealing resin layer forming the heat-sealing joint portion is thin, it may be considered that insulation failure may occur. Therefore, in order to prevent the occurrence of the above-mentioned insulation failure by making the function of the heat-fusion-bonded portion as an insulating layer more reliable, the heat-fusion-bonded portion has a melting point higher than that of the heat-fusion resin. You may interpose the insulator which it has, or the insulator which can hold | maintain a shape also in the heat-fusion temperature of the said heat-fusion resin.

【００１７】本発明で用いる一対の外装材は、それぞ
れ、一方の面に一部または全部の金属面が露出した少な
くとも一層の金属層を有する。この場合の一方の面は、
電池ケースを作製したときにその外面となるものであ
る。金属層の外面側の表面は少なくとも一部が外部に露
出した状態となっていればよく、必ずしも全部が外部に
露出している必要はない。金属層の一方の面が少なくと
も外部に露出した状態となっていれば、その露出した部
分を電極端子として利用できるからである。したがっ
て、金属層の外面に、一部に樹脂の存在しない部分を有
する樹脂層を設けて、当該樹脂の存在しない部分を金属
面露出部分とし、この金属面露出部分を電極端子として
利用するようにしてもよい（後述する本発明第４実施例
参照）。また、金属層の全面が露出した電池を、窓部を
有する一対のラミネートフィルムで上下からラミネート
してもよい。このような構造にすれば、金属板との接触
によるショートが回避できる。Each of the pair of exterior materials used in the present invention has at least one metal layer in which a part or all of the metal surface is exposed on one surface. One side of this case is
This is the outer surface when the battery case is manufactured. It suffices that at least a part of the outer surface of the metal layer is exposed to the outside, and the entire surface is not necessarily exposed to the outside. This is because, if at least one surface of the metal layer is exposed to the outside, the exposed portion can be used as an electrode terminal. Therefore, on the outer surface of the metal layer, a resin layer having a part where the resin does not exist is provided, and the part where the resin does not exist is the metal surface exposed part, and this metal surface exposed part is used as an electrode terminal. (See the fourth embodiment of the present invention described later). Further, the battery in which the entire surface of the metal layer is exposed may be laminated from above and below with a pair of laminating films having a window portion. With such a structure, a short circuit due to contact with the metal plate can be avoided.

【００１８】各外装材においてその反対側となる面、つ
まり電池ケースにおいて内面となる各外装材における他
方の面は、金属面であってもなくてもよい。金属層が一
層の場合は当該他方の面は当然に金属面となるが、本発
明はこのようなものに限られない。すなわち、本発明で
は、電池ケースを構成する外装材として、例えば、金属
層からなる単層体、金属層の片面に樹脂層を設けた積層
体、金属層と金属層との間に樹脂層を設けた積層体、金
属層の片面もしくは両面の一部に樹脂層を設けて当該金
属層の片面もしくは両面の一部が露出するように前記樹
脂層の一部を除去した積層体などを使用することができ
る。The surface on the opposite side of each exterior material, that is, the other surface of each exterior material, which is the inner surface of the battery case, may or may not be a metal surface. When the number of metal layers is one, the other surface is naturally a metal surface, but the present invention is not limited to this. That is, in the present invention, as the exterior material constituting the battery case, for example, a single-layer body made of a metal layer, a laminate having a resin layer on one surface of the metal layer, a resin layer between the metal layer and the metal layer. A laminated body provided, a laminated body in which a resin layer is provided on a part of one side or both sides of a metal layer, and a part of the resin layer is removed so that a part of one side or both sides of the metal layer is exposed is used. be able to.

【００１９】更に具体的には、各外装材として、例え
ば、金属層の片面に熱融着樹脂層を設けてなる積層体を
用いることができる。この場合は、正極集電体および負
極集電体に、正極用のリード端子および負極用のリード
端子の各一端をそれぞれ接続したうえで、正極用のリー
ド端子の他端側は、前記熱融着接合部を通って電池ケー
スの外側に導出して一方の外装材における金属層に接続
し、負極用のリード端子の他端側は、正極用のリード端
子と非接触状態を保ちつつ前記熱融着接合部を通って電
池ケースの外側に導出して他方の外装材における金属層
に接続した構成とすることができる（後述する実施例１
参照）。なお、このようにして得られた電池を、窓部を
有する一対のラミネートフィルムで上下からラミネート
してもよいことは言うまでもない。More specifically, as each of the exterior materials, for example, a laminate having a heat-sealing resin layer on one surface of a metal layer can be used. In this case, one end of each of the lead terminal for the positive electrode and the lead terminal for the negative electrode is connected to the positive electrode current collector and the negative electrode current collector, respectively, and the other end side of the lead terminal for the positive electrode is It is led out to the outside of the battery case through the adhesive joint and connected to the metal layer in one of the outer casings, and the other end of the lead terminal for the negative electrode is kept in a non-contact state with the lead terminal for the positive electrode. It can be configured to be led out to the outside of the battery case through the fusion-bonded portion and connected to the metal layer in the other exterior material (Example 1 described later).
reference). Needless to say, the battery thus obtained may be laminated from above and below with a pair of laminating films having a window portion.

【００２０】また、セル室側（電池ケース内面側）にお
いて金属層の一部または全部を露出させた状態とし、そ
の一方の金属層の露出部に正極集電体を電気的に接続す
るとともに、他方の金属層の露出部に負極集電体を電気
的に接続した構成とすることもできる（後述する実施例
２参照）。この場合、電池ケース内面側の金属層露出部
に集電体を密着させれば両者が電気的に接続されるよう
になるが、金属層露出部に集電体を溶接すれば、両者の
電気的接続をさらに確実なものとすることができる。In addition, a part or all of the metal layer is exposed on the cell chamber side (battery case inner surface side), and the positive electrode current collector is electrically connected to the exposed portion of one of the metal layers. A negative electrode current collector may be electrically connected to the exposed portion of the other metal layer (see Example 2 described later). In this case, if the current collector is brought into close contact with the exposed metal layer on the inner surface of the battery case, the two will be electrically connected. Connection can be made more reliable.

【００２１】本発明は、一次電池、水性電解液二次電
池、非水電解液二次電池、ポリマー電解質二次電池のい
ずれに適用できるものであるが、リチウムイオン二次電
池、ポリマー電解質二次電池が特に好まれる。The present invention can be applied to any of a primary battery, an aqueous electrolyte secondary battery, a non-aqueous electrolyte secondary battery, and a polymer electrolyte secondary battery. The lithium ion secondary battery, the polymer electrolyte secondary battery Batteries are particularly preferred.

【００２２】[0022]

【実施例】（第１実施例）図１および図２は本発明をリ
ウチムイオン二次電池（以下、単に電池という）に適用
した一例を示すもので、図１はその平面図、図２は図１
のＡ−Ａ線で切断してその内部構造を一部省略した状態
で示す断面図である。(First Embodiment) FIGS. 1 and 2 show an example in which the present invention is applied to a lithium ion secondary battery (hereinafter, simply referred to as a battery). FIG. 1 is a plan view thereof and FIG. 1
FIG. 4 is a cross-sectional view showing a state in which the internal structure is partially omitted by cutting along the line AA in FIG.

【００２３】この電池１は、平面視（図１の状態）で長
方形の電池ケース２を有する。電池ケース２は、図１お
よび図２に示すように、凹部３１を有する第１外装材３
と、この第１外装材３の凹部３１の開口端を密封する平
板状の第２外装材４とからなる。The battery 1 has a rectangular battery case 2 in plan view (state of FIG. 1). As shown in FIGS. 1 and 2, the battery case 2 includes a first exterior material 3 having a recess 31.
And a flat plate-shaped second exterior material 4 for sealing the open end of the recess 31 of the first exterior material 3.

【００２４】第１外装材３には、厚み６０μｍの鉄板
（金属層、以下Ｆｅ板という）３ａの片面に厚み３０μ
ｍの無延伸ポリプロピレン（熱融着樹脂）フィルム３ｂ
を積層してなる一枚のフィルム状積層体が用いられてい
る。第１外装材３は、前記積層体を押し金型を用いて凹
部３１を有する皿状の形状に加工することにより作製さ
れており、これの開口端の周縁部には、その全周にわた
って平坦なフランジ部３２が形成されている。The first exterior material 3 has an iron plate (metal layer, hereinafter referred to as Fe plate) 3a having a thickness of 60 μm and a thickness of 30 μ on one side.
m non-stretched polypropylene (heat fusion resin) film 3b
A single film-like laminated body formed by laminating is used. The first exterior material 3 is produced by processing the laminated body into a dish shape having a recess 31 using a pressing die, and the peripheral edge portion of the opening end of the first exterior material 3 is flat over the entire circumference. The flange portion 32 is formed.

【００２５】第２外装材４には、厚み４０μｍのアルミ
ニウム板（金属層、以下Ａｌ板という）４ａの片面に厚
み３０μｍの無延伸ポリプロピレンフィルム４ｂを積層
してなる一枚のフィルム状積層体が用いられている。第
２外装材４は、前記積層体を所定形状に切断あるいは打
ち抜くことにより作製されている。この第２外装材４
は、その周縁の形状およびサイズが、第１外装材３にお
けるフランジ部３２の外周縁の形状およびサイズと同一
とされている。The second exterior material 4 is a film-like laminated body obtained by laminating an unstretched polypropylene film 4b having a thickness of 30 μm on one surface of an aluminum plate (metal layer, hereinafter referred to as an Al plate) 40 a having a thickness of 40 μm. It is used. The second exterior material 4 is produced by cutting or punching the laminate into a predetermined shape. This second exterior material 4
Has the same shape and size as the outer circumference of the flange portion 32 of the first exterior material 3.

【００２６】第２外装材４は、第１外装材３のフランジ
部３２の無延伸ポリプロピレンフィルム３ｂ側の面に、
これに対向する第２外装材４の周縁部の無延伸ポリプロ
ピレンフィルム４ｂ側の面が、後述するように無延伸ポ
リプロピレンフィルム等（図示せず）を介して熱融着接
合されていることにより、第１外装材３と一体化されて
いる。そして、この接合一体化された第２外装材４で第
１外装材３の凹部３１の開口端が密封されることによ
り、当該凹部３１内（電池ケース２内、つまりセル室）
が気密および液蜜の状態に保たれるとともに、当該熱融
着接合部Ｍに存在するポリプロピレン層（熱融着樹脂
層）によって、第１外装材３を構成しているＦｅ板３ａ
と第２外装材４を構成しているＡｌ板４ｂとが電気的に
絶縁されるようになっている。The second exterior material 4 is formed on the surface of the flange portion 32 of the first exterior material 3 on the side of the non-stretched polypropylene film 3b.
By facing the non-stretched polypropylene film 4b side surface of the peripheral portion of the second exterior material 4 facing this by heat fusion bonding via a non-stretched polypropylene film or the like (not shown) as described later, It is integrated with the first exterior material 3. Then, the opening end of the recess 31 of the first exterior material 3 is sealed by the second exterior material 4 that is joined and integrated, so that the interior of the recess 31 (in the battery case 2, that is, the cell chamber) is sealed.
Is kept airtight and liquid, and the polypropylene layer (heat-sealing resin layer) existing in the heat-sealing joint portion M constitutes the first sheathing material 3 Fe plate 3a.
The Al plate 4b forming the second exterior material 4 is electrically insulated.

【００２７】第１外装材３の凹部３１内、すなわち電池
ケース２内には、発電体５および後述する電解液（図示
せず）などが収容されている。発電体５は、アルミニウ
ム箔からなる正極集電体（以下、Ａｌ箔集電体ともい
う）６ａの片面もしくは両面（図示例は両面）にＬｉＣ
ｏＯ₂ 系の活物質６ｂを塗工したシート状の正極６と、
銅箔からなる負極集電体（以下、Ｃｕ箔集電体ともい
う）７ａの片面もしくは両面（図示例は両面）にカーボ
ン系の活物質７ｂを塗工したシート状の負極７とを、こ
れらの間にポリエチレン微多孔膜からなるセパレータ
（例えば、８〜３０μｍ厚）８を介して折り畳むことに
よって形成されている。Inside the concave portion 31 of the first exterior material 3, that is, inside the battery case 2, a power generator 5 and an electrolyte solution (not shown) described later are housed. The power generator 5 has a LiC on one side or both sides (both sides in the illustrated example) of a positive electrode current collector (hereinafter also referred to as Al foil current collector) 6a made of aluminum foil.
a sheet-like positive electrode 6 coated with an oO ₂ -based active material 6b,
A sheet-shaped negative electrode 7 in which a carbon-based active material 7b is coated on one side or both sides (both sides in the illustrated example) of a negative electrode current collector (hereinafter also referred to as Cu foil current collector) 7a made of copper foil, It is formed by interposing a separator (for example, having a thickness of 8 to 30 μm) 8 made of a polyethylene microporous film between the two.

【００２８】シート状の正極６を構成しているＡｌ箔集
電体６ａ上には、アルミニウム製のリード端子（以下、
Ａｌリード端子ともいう）９の一端が超音波溶接されて
おり、当該リード端子９には、Ａｌ箔集電体６ａ上に配
置されたリード端子部分が完全に被覆されるように、ポ
リイミド樹脂テープ（図示せず）が貼付されている。同
様に、シート状の負極７を構成しているＣｕ箔集電体７
ａ上には、ニッケル製のリード端子（以下、Ｎｉリード
端子ともいう）１０の一端が超音波溶接されており、当
該リード端子１０には、Ｃｕ箔集電体７ａ上に配置され
たリード端子部分が完全に被覆されるように、ポリイミ
ド樹脂テープ（図示せず）が貼付されている。そして、
正極側のＡｌ箔集電体６ａに接続されたＡｌリード端子
９は、電池ケース２の一辺側（図１における上辺側）の
熱融着接合部Ｍを通って外部に導出されたうえで、第２
外装材４のＡｌ板４ａに溶接され、負極側のＣｕ箔集電
体７ａに接続されたＮｉリード端子１０は、電池ケース
２の他の一片側（図１における下辺側）の熱融着接合部
Ｍを通って外部に導出されたうえで、第１外装材４のＦ
ｅ板３ａに溶接されている。このようにして、この実施
例における電池１では、第１外装材３の外面を形成して
いるＦｅ板３ａが負極７と等電位となる一方、これとは
反対側の第２外装材４の外面を形成しているＡｌ板４ａ
が正極６と等電位となるように構成されている。On the Al foil current collector 6a constituting the sheet-shaped positive electrode 6, a lead terminal made of aluminum (hereinafter,
One end of (Al lead terminal) 9 is ultrasonically welded, and the lead terminal 9 is a polyimide resin tape so that the lead terminal portion arranged on the Al foil current collector 6a is completely covered. (Not shown) is attached. Similarly, the Cu foil current collector 7 constituting the sheet-shaped negative electrode 7
One end of a nickel lead terminal (hereinafter, also referred to as a Ni lead terminal) 10 is ultrasonically welded on a, and the lead terminal 10 is a lead terminal arranged on the Cu foil current collector 7a. A polyimide resin tape (not shown) is attached so that the portion is completely covered. And
The Al lead terminal 9 connected to the positive electrode side Al foil current collector 6a is led out to the outside through the heat-sealing joint portion M on one side (upper side in FIG. 1) of the battery case 2, Second
The Ni lead terminal 10 welded to the Al plate 4a of the exterior material 4 and connected to the Cu foil current collector 7a on the negative electrode side is heat-bonded to the other one side (lower side in FIG. 1) of the battery case 2. After being led out to the outside through the portion M, the F of the first exterior material 4
It is welded to the e-plate 3a. Thus, in the battery 1 in this example, the Fe plate 3a forming the outer surface of the first outer package 3 has the same potential as the negative electrode 7, while the second outer package 4 on the opposite side of the Fe plate 3a has the same potential. Al plate 4a forming the outer surface
Are configured to have the same potential as the positive electrode 6.

【００２９】この第１実施例電池は、次のようにして作
製した。まず正極集電体となる厚み１３μｍのＡｌ箔集
電体の片面に６０μｍ厚のＬｉＣｏＯ₂ 系塗膜を塗工し
て、カレンダーロール・スリット切断によりシート状の
正極を作製するとともに、負極集電体となる８μｍ厚の
Ｃｕ箔集電体の片面に６５μｍ厚のカーボン系塗膜を塗
工して、カレンダーロール・スリット切断によりシート
状の負極を作製した。この発電体の寸法は、横５１mm×
縦８５mm×厚さ2.４mmである。The first embodiment battery was manufactured as follows. First, a 13 μm-thick Al foil current collector serving as a positive electrode current collector is coated with a 60 μm-thick LiCoO ₂ -based coating film on one side, and a sheet-shaped positive electrode is produced by calender roll / slit cutting. A 65 μm-thick carbon-based coating film was applied to one surface of a Cu foil current collector having a thickness of 8 μm, which was a body, and a sheet-shaped negative electrode was produced by calender roll slit cutting. The size of this power generator is 51 mm wide ×
The length is 85 mm and the thickness is 2.4 mm.

【００３０】次に、上記の正極を構成するＡｌ箔集電体
上に厚み５０μｍのＡｌリード端子を超音波溶接し、Ａ
ｌ箔集電体上に配置されたＡｌリード端子が完全に被覆
されるようにポリイミド樹脂テープを貼付した。同様
に、上記の負極を構成するＣｕ箔集電体上に厚み５０μ
ｍのＮｉリード端子を超音波溶接し、Ｃｕ箔集電体上に
配置されたＮｉリード端子が完全に被覆されるようにポ
リイミド樹脂テープを貼付した。そのうえで、シート状
の正極および負極を、これらの間に１５μｍ厚のポリエ
チレン微多孔膜からなるセパレータを介して折り畳んで
発電体を作製した。Next, an Al lead terminal having a thickness of 50 μm is ultrasonically welded onto the Al foil current collector which constitutes the above positive electrode, and A
A polyimide resin tape was attached so that the Al lead terminals arranged on the 1 foil current collector were completely covered. Similarly, a thickness of 50 μm is formed on the Cu foil current collector that constitutes the negative electrode.
The Ni lead terminal of m was ultrasonically welded, and a polyimide resin tape was attached so that the Ni lead terminal arranged on the Cu foil current collector was completely covered. Then, the sheet-shaped positive electrode and negative electrode were folded with a separator made of a polyethylene microporous film having a thickness of 15 μm interposed therebetween to produce a power generator.

【００３１】第１外装材として、厚み６０μｍ厚のＦｅ
板の片面に、厚み３０μｍの無延伸ポリプロピレンフィ
ルムが形成されているフィルム状積層体を用い、当該無
延伸ポリプロピレンフィルムが形成されている面が電池
内部になるように、押し金型を用いて、縦５５mm×横９
０mm×深さ3.３mmの凹部を有するように成型した。そし
て、その熱融着接合部となるべき周縁部（フランジ部）
の無延伸ポリプロピレンフィルム面上に厚み５０μｍ、
幅５mmの無延伸ポリプロピレンフィルムを配置した。さ
らに、この第１外装材における凹部内に上述の発電体
を、Ａｌリード端子とＮｉリード端子がそれぞれ異なる
熱融着接合部となるべき周縁部（熱融着部）辺より外部
に露出するようにして、挿入した。Fe having a thickness of 60 μm was used as the first exterior material.
A film-like laminate in which a non-stretched polypropylene film having a thickness of 30 μm is formed on one surface of the plate, and a pressing die is used so that the surface on which the non-stretched polypropylene film is formed is inside the battery, Length 55 mm x width 9
It was molded so as to have a recess of 0 mm x 3.3 mm in depth. Then, the peripheral edge portion (flange portion) to be the heat-sealed joint portion.
50 μm thick on the unstretched polypropylene film surface of
An unstretched polypropylene film with a width of 5 mm was placed. Further, the above-mentioned power generation body is exposed to the outside in the concave portion of the first exterior material from the peripheral edge portion (heat fusion bonding portion) side where the Al lead terminal and the Ni lead terminal should be different heat fusion bonding portions. I inserted it.

【００３２】他方、第２外装材として、厚み４０μｍの
Ａｌ板の片面に厚み３０μｍの無延伸ポリプロピレンフ
ィルムが形成されているフィルム状積層体を用い、その
熱融着接合部となるべき周縁部に、厚み５０μｍ、幅５
mmの無延伸ポリプロピレンフィルムと、厚み５０μｍ、
幅５mmの架橋型ポリプロピレンフィルムの２層が形成さ
れているフィルムを配置した。そのうえで、前記発電体
が挿入された第１外装材の凹部を閉蓋するように、第１
外装材の凹部開口端側の面に第２外装材を重ねた。On the other hand, as the second exterior material, a film-like laminate in which an unstretched polypropylene film having a thickness of 30 μm is formed on one surface of an Al plate having a thickness of 40 μm is used, and a peripheral edge portion to be a heat-sealed joint is used. , Thickness 50μm, width 5
mm unstretched polypropylene film, thickness 50 μm,
A film having two layers of a cross-linked polypropylene film having a width of 5 mm was arranged. On top of that, the first exterior member in which the power generator is inserted is closed so as to close the recess.
The second exterior material was overlaid on the surface of the exterior material on the opening end side of the recess.

【００３３】次に、このようにして第１外装材および第
２外装材を重ね合わせた状態において、その熱融着接合
部となるべき周縁部の１辺のみを電解液注入用の注液口
として残して、３mm幅のヒートブロックにより当該周縁
部を１８０℃３秒条件で加圧融着した。電解液には、エ
チレンカーボネート（ＥＣ）とジエチルカーボネート
（ＤＥＣ）とを体積比で１：３に混合（ＥＣ：ＤＥＣ＝
１：３）した溶媒に電解質としてＬｉＰＦ₆ を1.２ｍｏ
ｌの濃度で溶解したものを使用し、これを上記注液口と
して残した未熱融着辺より大気圧下での注液法にて注入
（注入量は3.５cc）した。その後、１０Ｔｏｒｒ（１３
３０Ｐａ）以下に減圧した状態で未熱融着辺を上記と同
じ条件にて熱融着して密閉した。Next, in the state where the first exterior material and the second exterior material are overlapped with each other in this manner, only one side of the peripheral edge portion to be the heat fusion-bonded portion is injected into the electrolyte injection port. Then, the peripheral portion was pressure-bonded by a heat block having a width of 3 mm under the condition of 180 ° C. for 3 seconds. In the electrolytic solution, ethylene carbonate (EC) and diethyl carbonate (DEC) were mixed at a volume ratio of 1: 3 (EC: DEC =
1: 3) LiPF ₆ as an electrolyte in a solvent of 1.2mo
What was melt | dissolved at the density | concentration of 1 was used, and this was inject | poured by the injection method under atmospheric pressure from the non-heat-bonding side left as said injection port (injection amount is 3.5cc). Then 10 Torr (13
Under a reduced pressure of 30 Pa) or less, the non-heat-bonded side was heat-bonded and hermetically sealed under the same conditions as above.

【００３４】さらに、外部に露出させたリード端子をそ
れぞれ、Ａｌリード端子は第２外装材４のＡｌ板方向
に、Ｎｉリード端子は第１外装材３のＦｅ板方向に折り
曲げて、Ａｌリード端子は第２外装材のＡｌ板と、Ｎｉ
リード端子は第１外装材のＦｅ板と、それぞれ熱融着部
において超音波溶接を用いて接続して電池を作製した。Further, the lead terminals exposed to the outside are respectively bent by bending the Al lead terminal toward the Al plate of the second exterior material 4 and the Ni lead terminal toward the Fe plate of the first exterior material 3 to form the Al lead terminal. Is the Al plate of the second exterior material and Ni
The lead terminal was connected to the Fe plate of the first exterior material using ultrasonic welding at each heat-sealed portion to manufacture a battery.

【００３５】このような電池構造によれば、第１外装材
３のフランジ部３２と第２外装材４の周縁部とを無延伸
ポリプロピレンフィルムを介して熱融着接合することに
よって電池ケース２を形成することができるので、ラミ
ネートフィルム電池の場合のように機器の形状に合わせ
た電池形状とすることが比較的容易である。したがっ
て、形状自由度の高い電池を提供できる。According to such a battery structure, the flange 32 of the first outer casing 3 and the peripheral portion of the second outer casing 4 are heat-sealed to each other through the non-stretched polypropylene film to form the battery case 2. Since it can be formed, it is relatively easy to form a battery shape that matches the shape of the device as in the case of a laminated film battery. Therefore, a battery with a high degree of freedom in shape can be provided.

【００３６】また、電池ケース２の一方の外面およびこ
れと反対側の他方の外面をそれぞれ形成している第１外
装材３のＦｅ板３ａおよび第２外装材４のＡｌ板４ａ
が、熱融着接合部Ｍにおいて互いに電気的に絶縁された
状態で、それぞれ負極７および正極６と等電位とされて
いるから、前者のＦｅ板３ａを負極端子として、また後
者のＡｌ板４ａを正極端子として利用することができ
る。すなわち、これらに機器側の所定部分を直接接触さ
せるだけで、電池１からの電気エネルギーの取り出しが
可能となる。また、電池ケース２の両外面を形成してい
る第１外装材３のＦｅ板３ａおよび第２外装材４のＡｌ
板４ａがそれぞれ負極端子および正極端子となるので、
ラミネートフィルム電池では必要であった電池内電極端
子群の外部への引き出し部分が不要となる。したがっ
て、そのような引き出し部分が存在することによる体積
ロスを大幅に減少させることができ、その分だけ体積効
率が向上することになる。Further, the Fe plate 3a of the first exterior material 3 and the Al plate 4a of the second exterior material 4 which respectively form one outer surface of the battery case 2 and the other outer surface on the opposite side thereof.
, Which are electrically insulated from each other in the heat-sealing joint M and have the same potential as the negative electrode 7 and the positive electrode 6, respectively. Therefore, the former Fe plate 3a serves as the negative electrode terminal and the latter Al plate 4a. Can be used as a positive electrode terminal. That is, electric energy can be taken out from the battery 1 only by directly contacting these with a predetermined portion on the device side. In addition, the Fe plate 3a of the first exterior material 3 and the Al of the second exterior material 4 forming both outer surfaces of the battery case 2
Since the plate 4a serves as a negative electrode terminal and a positive electrode terminal, respectively,
The laminated film battery does not require a portion for drawing out the battery internal electrode terminal group to the outside, which is necessary. Therefore, the volume loss due to the existence of such a drawn-out portion can be greatly reduced, and the volumetric efficiency is improved accordingly.

【００３７】（第２実施例）上記の第１実施例に係る電
池では、第１外装材３および第２外装材４として、所定
の金属板の片面に無延伸ポリプロピレン（熱融着樹脂）
フィルムを積層してなるフィルム状積層体をそれぞれ使
用したが、この第２実施例に係る電池では、一対の外装
材として、それぞれ所定の金属板からなる単層体が使用
されている。(Second Embodiment) In the battery according to the first embodiment, as the first outer packaging material 3 and the second outer packaging material 4, unstretched polypropylene (heat sealing resin) is provided on one surface of a predetermined metal plate.
The film-like laminates obtained by laminating the films were used, but in the battery according to the second embodiment, the single-layered body made of a predetermined metal plate is used as the pair of exterior materials.

【００３８】図３は、第２実施例に係る電池１の断面構
造を示したものである。電池ケース２を構成する第１外
装材３および第２外装材４の外観形状等の基本的な構造
は第１実施例の場合とほぼ同じである。すなわち、第１
外装材（平面視で長方形）３が皿状に形成されて凹部３
１およびフランジ部３２を有する点、平板状の第２外装
材４が第１外装材３における凹部３１の開口端側に接合
されてこれを密封している点等は、第１実施例の場合と
同じである。異なるのは、一対の外装材３・４と発電体
５の構造、および各外装材３・４を構成している金属層
と発電体５における正極６・負極７との電気的接続構
造、リード端子９・１０の有無等である。FIG. 3 shows a sectional structure of the battery 1 according to the second embodiment. The basic structures such as the external shapes of the first exterior material 3 and the second exterior material 4 which form the battery case 2 are almost the same as those in the first embodiment. That is, the first
The exterior material (rectangular in plan view) 3 is formed in a dish shape to form the recess 3
1 and the flange portion 32, the flat plate-shaped second exterior material 4 is joined to the opening end side of the concave portion 31 in the first exterior material 3 and seals the same, and the like in the case of the first embodiment. Is the same as. The differences are the structure of the pair of exterior materials 3 and 4 and the power generation body 5, the electrical connection structure between the metal layer forming each exterior material 3 and 4 and the positive electrode 6 and the negative electrode 7 in the power generation body 5, and the leads. The presence / absence of the terminals 9 and 10.

【００３９】図３に示した電池１においては、第１外装
材３は厚み１００μｍの銅板（以下、Ｃｕ板という）３
ａからなり、第２外装材４は厚み８０μｍのアルミニウ
ム板（以下、Ａｌ板という）４ａからなる。第２外装材
４の周縁部は、第１外装材３のフランジ部３２の表面
に、後述する無延伸ポリプロピレンフィルム３ｂ・４ｂ
を介して熱融着接合されていることにより、第１外装材
３と一体化されている。そして、この接合一体化された
第２外装材４で第１外装材３の凹部３１の開口端側が密
封されることにより、当該凹部３１内（電池ケース２
内）が気密および液蜜の状態に保たれるとともに、当該
熱融着接合部Ｍに存在するポリプロピレン層（熱融着樹
脂層）によって、第１外装材３のＣｕ板３ａと第２外装
材４のＡｌ板４ｂとが電気的に絶縁されるようになって
いる。In the battery 1 shown in FIG. 3, the first exterior material 3 is a copper plate (hereinafter referred to as a Cu plate) 3 having a thickness of 100 μm.
The second exterior material 4 is made of an aluminum plate (hereinafter referred to as Al plate) 4a having a thickness of 80 μm. The peripheral portion of the second exterior material 4 is formed on the surface of the flange portion 32 of the first exterior material 3 by a non-stretched polypropylene film 3b, 4b described later.
It is integrated with the first exterior material 3 by being heat fusion bonded via. Then, by sealing the opening end side of the recess 31 of the first exterior material 3 with the second exterior material 4 that has been joined and integrated, the inside of the recess 31 (the battery case 2
The inside) is kept airtight and liquid, and the polypropylene layer (heat-sealing resin layer) present in the heat-sealing joint M causes the Cu plate 3a of the first sheath 3 and the second sheathing material No. 4 Al plate 4b is electrically insulated.

【００４０】第１外装材３の凹部３１内、つまり電池ケ
ース２内には、第１実施例の場合と同じく発電体５およ
び後述する電解液（図示せず）などが収容されている
が、この場合の発電体５の構造は第１実施例におけるも
のとは異なっている。すなわちこの第２実施例電池にお
ける発電体５は、アルミニウム箔からなる正極集電体
（Ａｌ箔集電体）６ａの両面（片面でもよい、図示例は
両面）にＬｉＣｏＯ₂ 系の活物質６ｂを塗工したシート
状の正極６と、銅箔からなる負極集電体（Ｃｕ箔集電
体）７ａの両面（片面でもよい、図示例は両面）にカー
ボン系の活物質７ｂを塗工したシート状の負極７とを、
ポリエチレン微多孔膜からなるセパレータ８を間にして
渦巻き状に捲回したのち、全体を第１外装材３の凹部３
１内に収容できるように当該凹部３１の断面形状に合わ
せて断面長円形状に押しつぶし変形して形成してある。In the recess 31 of the first exterior material 3, that is, in the battery case 2, the power generator 5 and an electrolytic solution (not shown) described later are accommodated as in the case of the first embodiment. The structure of the power generator 5 in this case is different from that in the first embodiment. That is, in the power generator 5 of the second embodiment battery, the LiCoO ₂ based active material 6b is provided on both sides (may be one side, both sides in the illustrated example) of the positive electrode current collector (Al foil current collector) 6a made of aluminum foil. A sheet in which a carbon-based active material 7b is coated on both sides (may be one side, both sides in the illustrated example) of a coated sheet-shaped positive electrode 6 and a negative electrode current collector (Cu foil current collector) 7a made of copper foil. The negative electrode 7
After being wound in a spiral shape with a separator 8 made of a polyethylene microporous film in between, the whole is made into the concave portion 3 of the first exterior material 3.
It is formed by being crushed and deformed into an oval cross-section in accordance with the cross-sectional shape of the concave portion 31 so that it can be accommodated in 1.

【００４１】そして、図示のように、発電体５が電池ケ
ース２内に収容された状態において、正極集電体である
Ａｌ箔集電体６が第２外装材４のＡｌ板４ａの内面に接
触し、負極集電体であるＣｕ箔集電体７ａが第１外装材
３のＣｕ板３ａの内面に接触した構成とされている。こ
のようにして、この実施例における電池では、第１外装
材３および第２外装材３の各金属層３ａ・４ａの内面
に、それぞれ、対応する電極の集電体７ａ・６ａが接触
していることにより、第１外装材３のＣｕ板３ａが負極
７と等電位となる一方、第２外装材４のＡｌ板４ａが正
極６と等電位となるように構成されている。したがっ
て、この電池には、第１実施例電池で用いたようなリー
ド端子９・１０（図１および図２参照）は設けられてお
らず、そのぶん構造が簡素化されている。Then, as shown in the figure, in a state where the power generator 5 is housed in the battery case 2, the Al foil current collector 6 which is the positive electrode current collector is provided on the inner surface of the Al plate 4a of the second exterior material 4. The Cu foil current collector 7a that is in contact with the negative electrode current collector is in contact with the inner surface of the Cu plate 3a of the first exterior material 3. Thus, in the battery of this embodiment, the current collectors 7a and 6a of the corresponding electrodes are in contact with the inner surfaces of the metal layers 3a and 4a of the first and second outer packaging materials 3 and 3, respectively. Accordingly, the Cu plate 3a of the first exterior material 3 has the same potential as the negative electrode 7, while the Al plate 4a of the second exterior material 4 has the same potential as the positive electrode 6. Therefore, this battery is not provided with the lead terminals 9 and 10 (see FIGS. 1 and 2) used in the battery of the first embodiment, and the structure is simplified accordingly.

【００４２】なお、上記のような巻回構造の発電体５を
電池ケース２内に収容するに当たり、正極側のＡｌ集電
体６ａが第２外装材４の内面に接触し且つ負極側のＣｕ
箔集電体７ａが第１外装材３の内面に接触した状態とす
るには、例えば、一方の電極と他方の電極の巻回方向に
おける終端部側の位置をずらすか、あるいは一方の電極
の終端部側を所定サイズ分だけ除去するといった方法が
考えられる。When accommodating the power generator 5 having the winding structure as described above in the battery case 2, the Al current collector 6a on the positive electrode side is in contact with the inner surface of the second exterior material 4 and Cu on the negative electrode side is formed.
To bring the foil current collector 7a into contact with the inner surface of the first exterior material 3, for example, the positions of one electrode and the other electrode on the terminal end side in the winding direction may be shifted, or A method of removing the end portion side by a predetermined size can be considered.

【００４３】この電池は、次のようにして作製した。ま
ず、６０μｍのＬｉＣｏＯ₂ 系塗膜を１５μｍ厚のＡｌ
箔集電体上の一部両面（片面でもよい）に塗工して、カ
レンダーロール・スリット切断によりシート状の正極を
作製するとともに、６５μｍのカーボン系塗膜を１０μ
ｍ厚のＣｕ箔集電体上の一部両面（片面でもよい）に塗
工し、カレンダーロール・スリット切断によりシート状
負極を作製した。そして、これらのシート状の正極およ
び負極を、その間に１５μｍ厚のポリエチレン微多孔膜
からなるセパレータを介して捲回・圧縮して縦１３mm×
横１４mm×厚さ5.１mmの発電体を作製した。その際、片
面にＡｌ箔集電体、他面にＣｕ箔集電体が露出するよう
にした。This battery was manufactured as follows. First, a 60 μm LiCoO ₂ -based coating is applied to a 15 μm thick Al film.
A sheet-shaped positive electrode is produced by coating a part of both sides (may be one side) on the foil current collector, and by calender roll / slit cutting, a 65 μm carbon-based coating film is applied to 10 μm.
A sheet-shaped negative electrode was produced by coating a part of both surfaces (may be one surface) of a m-thick Cu foil current collector and calender roll / slit cutting. Then, these sheet-shaped positive and negative electrodes are wound and compressed with a separator made of a polyethylene microporous film having a thickness of 15 μm interposed therebetween, and the length is 13 mm ×
A power generator having a width of 14 mm and a thickness of 5.1 mm was produced. At that time, the Al foil current collector was exposed on one surface and the Cu foil current collector was exposed on the other surface.

【００４４】第１外装材として、厚み１００μｍのＣｕ
板を、押し金型を用いて縦１８mm×横１８mm×深さ5.３
mmの、凹部およびフランジ部を有する皿状に成型したも
の使用し、その熱融着接合部となるべき周縁部、つまり
フランジ部の表面に厚み５０μｍ、幅５mmの無延伸ポリ
プロピレンフィルムを配置した。次に、この第１外装材
の凹部の内面（Ｃｕ板と導通接触が可能な面）に負極集
電体としてのＣｕ箔集電体が接するように発電体を配置
した。As the first exterior material, Cu having a thickness of 100 μm is used.
18mm x 18mm x depth 5.3 using a pressing die
An unstretched polypropylene film having a thickness of 50 μm and a width of 5 mm was arranged on the peripheral edge portion to be the heat-sealing joint, that is, on the surface of the flange portion. Next, the power generator was arranged such that the Cu foil current collector serving as the negative electrode current collector was in contact with the inner surface (the surface capable of conducting contact with the Cu plate) of the recess of the first exterior material.

【００４５】一方、第２外装材には厚み８０μｍのＡｌ
板を使用し、その熱融着接合部となるべき周縁部に、厚
み５０μｍ、幅５mmの無延伸ポリプロピレンフィルムを
配置した。そして、このＡｌ板からなる第２外装材を、
上記発電体が挿入された第１外装材（Ｃｕ板）における
凹部が第２外装材によって閉蓋されるように、当該凹部
の開口面側に重ねた。この際、第２外装材のＡｌ板と発
電体の正極のＡｌ箔集電体とが接触するようにした。On the other hand, the second exterior material is made of Al having a thickness of 80 μm.
A plate was used, and an unstretched polypropylene film having a thickness of 50 μm and a width of 5 mm was arranged on the peripheral edge portion to be the heat-sealed joint. Then, the second exterior material made of this Al plate is
The first exterior material (Cu plate) in which the power generator was inserted was placed on the opening surface side of the recess so that the recess was closed by the second exterior material. At this time, the Al plate of the second exterior material was brought into contact with the Al foil current collector of the positive electrode of the power generator.

【００４６】次に、このようにして第１外装材および第
２外装材を重ね合わせた状態において、その熱融着接合
部となるべき周縁部の１辺のみを電解液注入用の注液口
として残して、３mm幅のヒートブロックを用いて当該周
縁部を１８０℃、３秒の条件で加圧融着した。電解液に
は、第１実施例の場合と同様、エチレンカーボネート
（ＥＣ）とジエチルカーボネート（ＤＥＣ）とを体積比
で１：３に混合（ＥＣ：ＤＥＣ＝１：３）した溶媒に電
解質としてＬｉＰＦ₆ を1.２ｍｏｌの濃度で溶解したも
のを使用し、これを上記注液口として残した未熱融着辺
より減圧−加圧注液法にて注入した（注入量は0.４c
c）。その後、未熱融着辺を上記と同じ条件にて熱融着
して、第１外装材の凹部が第２外装材によって密閉され
た電池を作製した。Next, in the state where the first exterior material and the second exterior material are overlapped with each other in this manner, only one side of the peripheral edge portion to be the heat fusion-bonded portion is injected into the electrolyte injection port. Using the heat block having a width of 3 mm, the peripheral portion was pressure-bonded at 180 ° C. for 3 seconds. As in the case of the first embodiment, the electrolytic solution was prepared by mixing ethylene carbonate (EC) and diethyl carbonate (DEC) in a volume ratio of 1: 3 (EC: DEC = 1: 3) in a solvent, and LiPF as an electrolyte. ₆ dissolved at a concentration of 1.2 mol was used, and this was injected from the unheated fusion side left as the above injection port by the pressure reduction-pressure injection method (the injection amount was 0.4c.
c). After that, the non-heat-bonded side was heat-bonded under the same conditions as above, to fabricate a battery in which the concave portion of the first exterior material was sealed by the second exterior material.

【００４７】このような電池によれば、第１実施例と同
様に形状自由度および体積効率の向上が図れる。加え
て、第１実施例電池よりも構造が簡素になる。According to such a battery, the degree of freedom in shape and the volumetric efficiency can be improved as in the first embodiment. In addition, the structure is simpler than that of the first embodiment battery.

【００４８】（第３実施例）図４は本発明の第３実施例
を示すもので、この実施例の電池では第１外装材３のフ
ランジ部３２に第２外装材４の周縁部を熱融着接合する
に当たって、当該フランジ部３２および周縁部の両対向
面にそれぞれ配置された無延伸ポリプロピレンフィルム
３ｂ・４ｂ間にさらに絶縁体１５が配置され、そのうえ
で両外装材３・４が熱融着接合されていることにより、
両外装材３・４間の熱融着接合部Ｍに所定厚みの絶縁体
１５が介装された構造となっている。(Third Embodiment) FIG. 4 shows a third embodiment of the present invention. In the battery of this embodiment, the flange portion 32 of the first outer package 3 is heated to the peripheral portion of the second outer package 4. In fusion bonding, an insulator 15 is further disposed between the non-stretched polypropylene films 3b and 4b respectively disposed on both opposing surfaces of the flange portion 32 and the peripheral edge portion, and then both exterior materials 3 and 4 are heat-sealed. By being joined,
An insulating material 15 having a predetermined thickness is interposed in the heat-sealing joint portion M between the two exterior materials 3 and 4.

【００４９】この場合の絶縁体１５には、上記の無延伸
ポリプロピレンフィルム３ｂ・４ｂよりも融点の高いも
の、換言すれば熱融着接合温度においても形状を保持し
うるもの（例えば、セラミック、ガラス等の無機物質、
あるいはポリアミド、ポリイミド、エポキシ樹脂、ポリ
四フッ化エステル、シリコン樹脂、フェノール樹脂等の
比較的高融点の樹脂）が使用される。また、絶縁体１５
の平面視形状は、第１外装材１のフランジ部３２のそれ
に対応させて長方形の枠状であるが、その幅は、無延伸
ポリプロピレンフィルム３ｂ・４ｂによる熱融着接合を
妨げないように熱融着接合部Ｍの幅つまりフランジ部３
２の幅よりも所定寸法だけ狭い。In this case, the insulator 15 has a higher melting point than the above-mentioned unstretched polypropylene films 3b and 4b, in other words, one that can retain its shape even at the heat fusion bonding temperature (for example, ceramic, glass). Inorganic substances such as
Alternatively, a resin having a relatively high melting point such as polyamide, polyimide, epoxy resin, polytetrafluoroester, silicone resin or phenol resin is used. In addition, the insulator 15
Has a rectangular frame shape corresponding to that of the flange portion 32 of the first exterior material 1, but its width is set so as not to interfere with heat fusion bonding by the non-stretched polypropylene films 3b and 4b. The width of the fusion-bonded portion M, that is, the flange portion 3
It is narrower than the width of 2 by a predetermined size.

【００５０】このような絶縁体１５を図示のように熱融
着接合部Ｍに介装することによって、第１外装材３と第
２外装材４との間に少なくとも絶縁体１５の厚み分だけ
の間隔は確保されるから、熱融着接合後において両外装
材３・４間の電気的な絶縁状態を一層確実に保持するこ
とができる。なお、絶縁体１５に多孔性のものを使用す
れば、熱融着接合時に流動化したポリプロピレンの一部
が絶縁体１５の孔内に入り込むので、熱融着接合部Ｍに
存在するポリプロピレンと絶縁体１５との結合をさらに
高めることができる。By interposing such an insulator 15 in the heat-sealing joint M as shown in the drawing, at least the thickness of the insulator 15 is provided between the first exterior material 3 and the second exterior material 4. Since the space is secured, it is possible to more reliably maintain the electrically insulated state between the outer packaging materials 3 and 4 after the thermal fusion bonding. If a porous insulator 15 is used, a part of the polypropylene fluidized at the time of heat fusion bonding will enter into the holes of the heat insulator 15, so that it will be insulated from the polypropylene present at the heat fusion bonding portion M. The bond with the body 15 can be further enhanced.

【００５１】以上の点を除けば、図４に例示した電池の
構成も図３の第２実施例電池の構成と同じである。した
がって、第２実施例電池の各部と対応する部分について
は、図３と同様の符号を付してその説明を省略する。Except for the above points, the structure of the battery illustrated in FIG. 4 is the same as the structure of the second embodiment battery of FIG. Therefore, the parts corresponding to the respective parts of the second embodiment battery are designated by the same reference numerals as those in FIG. 3, and the description thereof will be omitted.

【００５２】（第４実施例）図５および図６は本発明の
第４実施例を示すもので、この実施例の電池１は、一部
に樹脂の存在しない部分（以下、窓部という）２５ａを
有する樹脂フィルム（樹脂層）２５により、先に述べた
第２実施例電池（図３参照）や第３実施例電池（図４参
照）の外面側を被覆したような構造としたものである。
すなわち、第１外装材３の金属層３ａと第２外装材４の
金属層４ａとを熱融着樹脂３ｂ・４ｂを介して接合し
て、発電体５等を収容する電池ケース２を形成し、両金
属層３ａ・４ａの外面を、前記窓部２５ａを有する樹脂
フィルム２５で被覆した構成である。(Fourth Embodiment) FIGS. 5 and 6 show a fourth embodiment of the present invention. In the battery 1 of this embodiment, a portion where no resin exists (hereinafter referred to as a window portion). The resin film (resin layer) 25 having 25a has a structure such that the outer surface side of the second embodiment battery (see FIG. 3) or the third embodiment battery (see FIG. 4) described above is covered. is there.
That is, the metal layer 3a of the first exterior material 3 and the metal layer 4a of the second exterior material 4 are joined via the heat-sealing resins 3b and 4b to form the battery case 2 that houses the power generator 5 and the like. The outer surfaces of both metal layers 3a and 4a are covered with the resin film 25 having the window portion 25a.

【００５３】このような電池１では、樹脂フィルム２５
の窓部２５ａにおいて両金属層３ａ・４ａの外面の一部
（図示例では両外面のそれぞれ中央部）３ａ’・４ａ’
が外部に露出した状態となるから、この部分（金属面一
部露出部分）３ａ’・４ａ’を電極端子として使用する
ことができる。樹脂フィルム２５は、金属層３ａ・４ａ
が傷付かないようにその外面を保護するとともに、外部
導電体との不用意な或いは不必要な接触による無駄な放
電等を抑制し、さらには電池ケース２の強度を全体とし
て高める機能を果たす。In such a battery 1, the resin film 25
Part of the outer surface of both metal layers 3a and 4a (in the illustrated example, the central portions of both outer surfaces) 3a 'and 4a' in the window portion 25a of
Is exposed to the outside, this portion (metal surface partially exposed portion) 3a 'and 4a' can be used as electrode terminals. The resin film 25 is made of metal layers 3a and 4a.
Protects the outer surface of the battery case from scratches, suppresses wasteful discharge due to careless or unnecessary contact with the external conductor, and further enhances the strength of the battery case 2 as a whole.

【００５４】樹脂フィルム２５は、電池ケース２の形成
後に両金属層３ａ・４ａの外面を覆うように設けられた
ものでもよいし、素材段階で各金属層３ａ・４ａの片面
にあらかじめ貼り付けられていたものであってもよい。
ただし、いずれの場合も電池ケース２を作製したとき
に、金属層３ａ・４ａの外面の一部が外部に露出するよ
うに、所要の位置に窓部２５ａが設けられている必要が
ある。なお、窓部２５ａの位置、つまり金属面一部露出
部分３ａ’・４ａ’の位置は、機器側の設計に合わせて
適宜変更できることは勿論である。The resin film 25 may be provided so as to cover the outer surfaces of both the metal layers 3a and 4a after the battery case 2 is formed, or may be attached to one surface of each of the metal layers 3a and 4a in advance at the material stage. It may be the one that was used.
However, in any case, when the battery case 2 is manufactured, the window 25a needs to be provided at a required position so that a part of the outer surfaces of the metal layers 3a and 4a are exposed to the outside. The position of the window portion 25a, that is, the position of the metal surface partially exposed portions 3a 'and 4a' can, of course, be appropriately changed according to the design of the device side.

【００５５】[0055]

【発明の効果】以上のように、本発明によれば、電池か
らの端子飛び出しが無く、電池ケースの外面に直接接触
させるだけで機器との電気的導通が図れるので、電池か
らのリード線の引き回しのロスを大幅に減少させた体積
効率の良い電池を提供することができる。しかも、ラミ
ネートフィルム電池における場合と同じく熱融着による
シール方法で電池ケースを作製できるので、機器の形状
に合わせた電池形状とすることが比較的容易である。し
たがって、形状自由度の高い電池を実現できる。加え
て、本発明はサイズの比較的大きな電池にも適用できる
という利点を有するが、このような利点はボタン型電池
やコイン型電池にはなかったものである。As described above, according to the present invention, there is no protrusion of terminals from the battery, and electrical connection with the device can be achieved by making direct contact with the outer surface of the battery case. It is possible to provide a battery with high volume efficiency in which routing loss is greatly reduced. Moreover, since the battery case can be manufactured by the sealing method by heat fusion as in the case of the laminated film battery, it is relatively easy to form the battery shape according to the shape of the device. Therefore, a battery having a high degree of freedom in shape can be realized. In addition, although the present invention has an advantage that it can be applied to a battery having a relatively large size, such an advantage is not found in a button type battery or a coin type battery.

[Brief description of drawings]

【図１】本発明の第１実施例に係る電池を、その一部を
切り欠いた状態で示す平面図である。FIG. 1 is a plan view showing a battery according to a first embodiment of the present invention with a part thereof cut away.

【図２】図１のＡ−Ａ線で切断した一部省略断面図であ
る。FIG. 2 is a partially omitted cross-sectional view taken along the line AA of FIG.

【図３】本発明の第２実施例に係る電池の一部省略断面
図である。FIG. 3 is a partially omitted sectional view of a battery according to a second embodiment of the present invention.

【図４】本発明の第３実施例に係る電池の一部省略断面
図である。FIG. 4 is a partially omitted sectional view of a battery according to a third embodiment of the present invention.

【図５】本発明の第４実施例に係る電池の平面図であ
る。FIG. 5 is a plan view of a battery according to a fourth embodiment of the present invention.

【図６】図５のＢ−Ｂ線で切断して一部簡略化した断面
図である。FIG. 6 is a partially simplified sectional view taken along line BB in FIG.

[Explanation of symbols]

１電池２電池ケース３・４一対の外装材（３・・・第１外装材，４・・
・第２外装材）３ａ・４ａ金属層３ａ’・４ａ’ 金属面一部露出部分３ｂ・４ｂ熱融着樹脂（無延伸ポリプロピレンフィル
ム）５発電体６正極６ａ正極集電体６ｂ正極活物質７負極７ａ負極集電体７ｂ負極活物質９・１０リード端子１５絶縁体２５樹脂フィルム２５ａ樹脂フィルムの窓部３２フランジ部Ｍ熱融着接合部DESCRIPTION OF SYMBOLS 1 Battery 2 Battery case 3 and 4 A pair of exterior materials (3 ... 1st exterior material, 4 ...
-Second exterior material) 3a, 4a Metal layer 3a ', 4a' Partly exposed surface of metal surface 3b, 4b Thermal fusion resin (unstretched polypropylene film) 5 Power generator 6 Positive electrode 6a Positive electrode current collector 6b Positive electrode active material 7 Negative electrode 7a Negative electrode current collector 7b Negative electrode active material 9/10 Lead terminal 15 Insulator 25 Resin film 25a Resin film window 32 Flange M Thermal fusion bond

───────────────────────────────────────────────────── フロントページの続きＦターム(参考） 5H011 AA03 AA04 BB04 CC02 CC06 CC10 EE04 FF03 FF04 GG09 5H022 AA09 CC03 CC08 CC16 EE01 ─────────────────────────────────────────────────── ─── Continued front page F-term (reference) 5H011 AA03 AA04 BB04 CC02 CC06 CC10 EE04 FF03 FF04 GG09 5H022 AA09 CC03 CC08 CC16 EE01

Claims

[Claims]

1. A battery in which a power generating element including a positive electrode and a negative electrode is housed in a battery case, wherein the battery case is composed of a pair of exterior materials, and each exterior material is one of It has at least one metal layer in which a part or all of the metal surface is exposed on the surface, and the peripheral portions of the other surface of both exterior materials are joined together via a heat-sealing resin, so that both A cell chamber accommodating the power generating element is formed between the exterior materials, and the metal layer in one of the exterior materials is electrically connected to the positive electrode so that the metal layer has the same potential as the positive electrode potential. At the same time, the metal layer of the other exterior material is electrically connected to the negative electrode so that the potential of the metal layer of the other exterior material is equal to the negative electrode potential. Is electrically isolated from the metal layer of the material Battery characterized by Rukoto.

2. The positive electrode has a positive electrode active material layer formed on one surface or both surfaces of a positive electrode current collector, and the negative electrode has a negative electrode active material layer formed on one surface or both surfaces of a negative electrode current collector. Batteries.

3. The battery according to claim 1, wherein the metal layer in one of the exterior materials and the metal layer in the other exterior material are made of different metals.

4. An insulator having a melting point higher than that of the heat-sealing resin, or an insulator capable of retaining its shape even at the heat-sealing temperature of the heat-sealing resin, at the heat-sealing joint portion of both outer packaging materials. The battery according to any one of claims 1 to 3, further comprising:

5. The one and / or the other exterior material is a single-layer body made of a metal layer, a laminate having a resin layer on one surface of the metal layer, or a resin layer between the metal layer and the metal layer. The battery according to any one of claims 1 to 4, which is constituted by any one of the provided laminated bodies.

6. Each of the outer packaging materials is composed of a laminated body in which a heat-sealing resin layer is provided on one surface of a metal layer, and the positive electrode current collector and the negative electrode current collector have a lead terminal for a positive electrode and a negative electrode. One end of each of the lead terminals for the positive electrode is connected to each other, and the other end of the lead terminal for the positive electrode is led to the outside of the battery case through the thermal fusion bonding part and connected to the metal layer of one of the exterior materials. At the same time, the other end of the lead terminal for the negative electrode is led to the outside of the battery case through the heat-sealing joint while keeping the non-contact state with the lead terminal for the positive electrode, and is connected to the metal layer of the other exterior material. The battery according to any one of claims 1 to 5, which is connected.

7. The pair of exterior materials are such that a part or all of the metal layer is exposed on the cell chamber side, and the positive electrode current collector is electrically connected to the exposed portion of one of the metal layers. The battery according to claim 1, wherein the negative electrode current collector is electrically connected to the exposed portion of the other metal layer.

8. The pair of exterior materials are such that a part or all of the metal layer is exposed on the cell chamber side, and the positive electrode current collector is adhered or welded to the exposed portion of one of the metal layers. The battery according to any one of claims 1 to 5, wherein the negative electrode current collector is adhered or welded to the exposed portion of the other metal layer.