JP4228376B2

JP4228376B2 - battery

Info

Publication number: JP4228376B2
Application number: JP22826399A
Authority: JP
Inventors: 達治中込; 徳雄稲益; 盛勝新井; 敏之温田
Original assignee: GS Yuasa Corp
Current assignee: GS Yuasa Corp
Priority date: 1999-08-12
Filing date: 1999-08-12
Publication date: 2009-02-25
Anticipated expiration: 2019-08-12
Also published as: JP2001052663A

Description

【０００１】
【発明の属する技術分野】
本発明は、金属樹脂複合材で外装された電池に関し、特に金属樹脂複合材で外装されたリチウム二次電池に関する。
【０００２】
【従来の技術】
近年、エレクトロニクス分野の発展に伴い電子機器の小型化がめざましい。特に携帯電話やＰＨＳ等の携帯機器類や小型パーソナルコンピュータの需要拡大は著しく、これらの機器類の軽薄短小化に伴い電源となる電池においても高機能化に加えて小型化・薄形化が求められている。しかし、これらの機器に従来使用されてきた電池は金属電槽缶を用いた円筒形及び角形が中心であった。
【０００３】
そこで、薄形化、軽量化という点において、金属樹脂複合材のような軟包装材を用いた電池の技術が過去に提案されている（特開昭５５−３５４６９号公報等）。また、発電要素として軽量である金属リチウム電池、リチウムイオン電池が注目されてきており、これを軟包装材で包装するタイプの電池についてもすでに提案されている（特開昭６２−５５８６５号公報等）。
【０００４】
【発明が解決しようとする課題】
しかしながら、従来の軟包装材を外装に用いたリチウム二次電池では、製造時に発電要素からの電流の取り出し口である端子と電極タブ部とを一緒にシール封止してしまうと、金属樹脂複合材内面の樹脂がシール時に加える熱により破壊され、端子と金属樹脂複合材とが短絡するといった問題があった。
【０００５】
また、端子部周縁は機械的強度が弱く、電池の使用時に、振動等によって端子と電極タブ部との接合部がはずれるといった問題があった。短絡を防止するために、プラスチック等の熱可塑性でない絶縁物を配置する方法もあるが、この場合には密着が充分でなく、振動等によって端子と電極タブ部との接合部がはずれるといった問題に対しては有効ではなかった。
【０００６】
また、従来の同タイプの電池においては、組み込み機器内において、発電要素以外のシール部分や端子部分がデッドスペースとなり、機器の小型化を阻害する要因となっていた。
【０００７】
本発明は、上記課題に鑑みなされたものであって、シール時の短絡不良の発生を低減し、接合部の耐振性を向上させ、機器組み込み時の体積効率を改善することを目的とする。
【０００８】
【課題を解決するための手段】
前記課題を解決する本出願第１の発明は、外装体に金属樹脂複合材を用いた電池であって、少なくとも一部が樹脂融着により封止され、正極および／または負極の端子が該融着部を貫通し、且つ、正極および／または負極の電極には少なくとも一箇所の電極タブ部を有し、該タブ部と端子とが少なくとも一箇所の接合箇所を有する電池において、前記端子と前記電極タブ部とが一緒に封止されないように前記接合箇所が電池系内の前記融着部から電極タブ部側に位置ずれして配され、前記接合箇所を含みかつ前記融着部とは異なる端子部分と、電極タブ部と、を熱可塑性樹脂シートで加圧して前記外装体と前記端子部分と前記電極タブ部とを密着固定する、ことを特徴とする電池である。
【０００９】
したがって、本出願第１の発明の電池によれば、端子と電極タブ部との接合部の耐振性を向上させることができる。
【００１０】
また、本出願第２の発明は、前記外装体の少なくとも一方に絞り加工を施している電池であり、本出願第３の発明は、前記外装体は、絞り加工を施していない金属樹脂複合材と絞り加工を施している金属樹脂複合材から成り、電池厚さをＴとしたとき、前記端子融着部厚さの中心位置及び前記絶縁材料で密着固定した部分の厚さの中心位置は、絞り加工を施していない電池外面から、絞り深さ方向に向かって１／４Ｔ以下の領域にあることを特徴とする電池である。
【００１１】
したがって、本出願第２および第３の発明の電池によれば、機器組み込み時の体積効率を改善することができる。
【００１２】
また、本出願第４の発明は、前記端子融着部は電極タブ部を含まず、前記端子融着部と電極タブの間に存在する端子部分の距離が０．１ｍｍ〜１０ｍｍである電池である。
【００１３】
したがって、本出願第４の発明の電池によれば、金属樹脂複合材と端子との短絡を防止し、良品率を向上させることができる。
【００１４】
【発明の実施の形態】
図１、２は本発明の実施の１形態を示す電池の平面図及び断面図である。金属樹脂複合材の外装体１は、外面がポリエチレンテレフタレート（ＰＥＴ）フィルム、内面がポリプロピレン（ＰＰ）フィルム、あるいは無水マレイン酸により変成されたＰＰフィルム、芯材がアルミニウム箔で構成された金属樹脂複合材を用いている。金属樹脂複合材の材質については、これに限定されるものではない。１’は、外装体のうち樹脂融着により封止された部分である。
【００１５】
２は負極端子であり、ニッケルを用いている。負極端子には銅やその合金を用いても良い。３は正極端子であり、アルミニウムを用いている。正極端子にはアルミニウム合金も使用可能である。端子の材質についてはこれらに限定されるものではない。また、負極端子２および正極端子３のうち破線で示した部分は、それぞれの端子の融着部と電極タブ部の間に存在する部分であり、端子融着部から電極タブ部までの距離は０．１ｍｍ〜１０ｍｍが望ましい。その理由は０．１ｍｍ以下では端子融着部と電極タブ部との距離の制御が難しく、短絡が起こり易くなり、１０ｍｍ以上では電池の重量及び体積が増してしまいエネルギー密度の低下をきたすためである。
【００１６】
負極板は、負極集電体４と負極合材層５からなり、銅箔からなる負極集電体４は、端子と接着するための負極タブ部４’を有している。負極合材層５は、リチウムイオンを吸蔵放出可能な炭素材料を用いている。
【００１７】
正極板は、正極集電体６と正極合材層７からなり、アルミ箔からなる正極集電体６は、端子と接着するためのタブ部６’を有している。正極合材層７は、リチウムイオンを吸蔵放出可能なリチウム含有酸化物を用いている。８は非水電解質を含むセパレータである。
【００１８】
外装体と発電要素を合わせた厚みをＴとする。９は圧力のみかけて封止されていない部分であり、該部分の厚さの中心位置は、絞り加工を施していない電池外面から、絞り深さ方向に向かって１／４Ｔ以下の領域にあることが望ましい。外装体１のうち樹脂融着により封止された部分１’の厚さの中心位置についても同様である。このような設計をする事により、これらの部分の上方に空間を設ける事ができるので、この空間に保護回路やリード線を配置することができる。また、この空間を利用して、組み込まれる機器の基板を配置する設計とすることもできる。
【００１９】
１０は電池系内において化学的、電気化学的に安定な熱可塑性樹脂シートである。具体的には、６ナイロン、６・６ナイロン、ポリ塩化ビニル、ポリエチレンやポリプロピレンなどポリオレフィン樹脂等熱可塑性樹脂、無水マレイン酸などにより変性されたポリエチレンやポリプロピレンなど酸変性ポリオレフィン樹脂やアイオノマー、ＥＶＡ、ＥＡＡのような金属接着性樹脂を用いる事ができるがこれらに限定されるものではない。
【００２０】
【実施例】
（本発明）
正極は、ＬｉＣｏＯ₂（活物質）、アセチレンブラック（導電材）およびＰＶＤＦ（バインダー）で構成される正極合材がアルミニウム箔（集電体）上に担持されている。負極は、繊維状黒鉛（活物質）、アセチレンブラック（導電材）およびＰＶＤＦ（バインダー）で構成される負極合材が銅箔（集電体）上に担持されている。この正極、負極は共にエチレンカーボネート（ＥＣ）、γ−ブチロラクトン（γ−ＢＬ）およびポリエチレンオキサイド（ＰＥＯ）系のモノマーを混合し、ＬｉＢＦ₄塩を溶解した溶液に含浸し、電子線照射によって溶液をゲル化した。
【００２１】
上記の正極と負極の間に、エチレンカーボネート（ＥＣ）、γ−ブチロラクトン（γ−ＢＬ）およびポリエチレンオキサイド（ＰＥＯ）系のモノマーを混合し、ＬｉＢＦ₄塩を溶解した溶液を厚さ２０μｍのポリプロピレンの不織布に含浸し、電離性放射線照射によってゲル化したものを電解質層兼セパレータとして用い、正極、セパレータおよび負極を積層し、電極体を作製した。但し、セパレータはポリマーゲルセパレータのみでなく、不織布あるいは微多孔性のセパレータに電解液を含浸したものを用いてもよい。
【００２２】
上記電極体を外面が厚さ約２０μｍのＰＥＴフィルム、内面が厚さ約３０μｍのＰＰフィルム、芯材が厚さ約５０μｍのアルミニウム箔で構成された金属樹脂複合材２枚を使って四辺を高周波シールによって封止した。この時、電池の端子のある辺については、端子と電極タブ部が一緒に封止されないように、端子溶着部と電極タブ部の間に隙間を０．５ｍｍ程度開け、その部分を覆うように熱可塑性樹脂シートを配し、電極タブ部は加圧して電極タブ部と端子との密着性を高め、端子の部分のみを高周波シールして図１、２に示す様な電池を作製した。熱可塑性樹脂シートには、無水マレイン酸変性ポリプロピレンを用いた。
【００２３】
（比較例１）
本発明と同様に電極体を作製し、上記と同じ材質の２枚の金属樹脂複合材で四辺を高周波シールで封止した。この時、端子溶着部が電極タブ部に０．５ｍｍ程度接触する様に高周波シールをした。また、封止する部分と重なっていない電極タブ部を覆う様に熱可塑性樹脂シートを置いて加圧し、電極タブと端子との密着性を高め、電池を作製した。
【００２４】
（比較例２）
本発明と同様に電極体を作製し、上記と同じ材質の２枚の金属樹脂複合材の四辺を高周波シールで封止した。この時、端子溶着部と電極タブ部との間の隙間を０．５ｍｍ程度開け、電極タブ部には熱可塑性樹脂シートを置かずに電池を作製した。
【００２５】
以下の２種類の方法で電池特性を測定し、比較検討を行った。第一の試験は、端子−金属樹脂複合材間の短絡を測定し（試験Ａ）、製造時のショートの発生率を比較検討した。第二の試験は、試験Ａで短絡の無かったものについて電池の端子部をぶら下げた状態で持ち上げ、そのまま加振機に端子部のみを固定し、１０Ｇをかけ、その後のインピーダンスを測定し（試験Ｂ）、電池の耐振性を比較検討した。この試験は、機器に装着される場合、端子部をもってで機器に固定される場合を想定したものである。結果を表１に示す。
【００２６】
【表】

【００２７】
表に示す通り、試験Ａにおいて、端子溶着部に電極タブ部を含まないものは、電極タブ部を含んでいるものに比べて端子−金属樹脂複合材間の短絡が大幅に減少し、良品率が飛躍的に向上した。また、試験Ｂにおいて加振試験後にインピーダンスが試験前に比べて２倍以上になった電池を解体してみると、端子と電極タブの接合部が破断していた。この結果より、熱可塑性樹脂シートを配置して圧力のみかけてシールしない部分を設けることにより、機械的な強度、耐振性ともに向上することがわかる。
【００２８】
【発明の効果】
以上説明したように、本発明によれば、シール封入時に電極タブを固定し、且つ金属樹脂複合材と端子との短絡を防止し、生産時の良品率を上昇させ、接合部の耐振性を向上させる事ができる。また、電極タブ部がある空間に保護回路やリード線を置くことができ、また、組み込んだ機器の基板を置くことが出来るのでエネルギー密度的にも有利な構造であり、工業的価値は極めて大である。
【図面の簡単な説明】
【図１】本発明のリチウム二次電池の一例を示す正面図である。
【図２】図１Ａ−Ａ部の一部断面図である。
【符号の説明】
１外装体
１’ 樹脂融着により封止された部分
２負極端子
３正極端子
４’ 負極タブ部
６’ 正極タブ部
１０熱可塑性樹脂シート[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a battery packaged with a metal resin composite material, and more particularly to a lithium secondary battery packaged with a metal resin composite material.
[0002]
[Prior art]
In recent years, with the development of the electronics field, downsizing of electronic devices is remarkable. In particular, the demand for mobile devices such as mobile phones and PHS and small personal computers is growing rapidly. As these devices become lighter, thinner, and smaller, batteries that serve as power sources need to be smaller and thinner in addition to higher functionality. It has been. However, the batteries conventionally used in these devices have been mainly cylindrical and rectangular using metal battery case cans.
[0003]
Therefore, in the past, a technique of a battery using a soft packaging material such as a metal resin composite material has been proposed in terms of reduction in thickness and weight (Japanese Patent Laid-Open No. 55-35469). In addition, lightweight metal lithium batteries and lithium ion batteries have attracted attention as power generation elements, and batteries of the type in which they are packaged with a flexible packaging material have already been proposed (Japanese Patent Laid-Open No. 62-55865). ).
[0004]
[Problems to be solved by the invention]
However, in the lithium secondary battery using the conventional soft packaging material for the exterior, if the terminal and the electrode tab part, which are the current extraction ports from the power generation element, are sealed together at the time of manufacture, the metal resin composite There was a problem that the resin on the inner surface of the material was destroyed by heat applied at the time of sealing, and the terminal and the metal resin composite material were short-circuited.
[0005]
Further, the peripheral edge of the terminal portion has a weak mechanical strength, and there is a problem that the joint between the terminal and the electrode tab portion is detached due to vibration or the like when the battery is used. In order to prevent short-circuiting, there is a method of disposing a non-thermoplastic insulator such as plastic, but in this case, the adhesion is not sufficient, and the problem is that the joint between the terminal and the electrode tab part is disconnected due to vibration or the like. It was not effective against it.
[0006]
Further, in the conventional battery of the same type, a seal portion and a terminal portion other than the power generation element in the embedded device become a dead space, which is a factor that hinders downsizing of the device.
[0007]
This invention is made | formed in view of the said subject, Comprising: It aims at reducing generation | occurrence | production of the short circuit defect at the time of sealing, improving the vibration resistance of a junction part, and improving the volume efficiency at the time of apparatus incorporation.
[0008]
[Means for Solving the Problems]
A first invention of the present application for solving the above-mentioned problems is a battery using a metal resin composite material for an exterior body, at least a part of which is sealed by resin fusion, and a positive electrode and / or a negative electrode terminal are fused. the wear part penetrates, and includes an electrode tab portion of the at least one place on the electrodes of the positive and / or negative electrode in a battery and the tab portion and the terminal has a joint of at least one place, the said terminal In order to prevent the electrode tab portion from being sealed together, the joint portion is arranged so as to be displaced from the fusion portion in the battery system toward the electrode tab portion side, includes the joint portion, and is different from the fusion portion. The battery is characterized in that the terminal portion and the electrode tab portion are pressed with a thermoplastic resin sheet to tightly fix the exterior body, the terminal portion, and the electrode tab portion .
[0009]
Therefore, according to the battery of the first invention of the present application, the vibration resistance of the joint portion between the terminal and the electrode tab portion can be improved.
[0010]
Further, the second invention of the present application is a battery in which at least one of the exterior bodies is subjected to a drawing process, and the third invention of the present application is a metal resin composite material in which the exterior body is not subjected to a drawing process. And when the battery thickness is T, the center position of the terminal fused portion thickness and the center position of the thickness of the portion closely fixed by the insulating material are: The battery is characterized by being in a region of 1 / 4T or less from the outer surface of the battery not subjected to drawing processing toward the drawing depth direction.
[0011]
Therefore, according to the batteries of the second and third inventions of the present application, the volumetric efficiency when the device is incorporated can be improved.
[0012]
The fourth invention of the present application is a battery in which the terminal fusion part does not include an electrode tab part, and a distance between the terminal part existing between the terminal fusion part and the electrode tab is 0.1 mm to 10 mm. is there.
[0013]
Therefore, according to the battery of the fourth invention of the present application, a short circuit between the metal resin composite material and the terminal can be prevented, and the yield rate can be improved.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2 are a plan view and a cross-sectional view of a battery showing an embodiment of the present invention. The metal resin composite exterior body 1 is composed of a polyethylene terephthalate (PET) film on the outer surface, a polypropylene (PP) film on the inner surface, a PP film modified with maleic anhydride, and a metal resin composite in which the core material is made of aluminum foil. The material is used. The material of the metal resin composite material is not limited to this. 1 ′ is a portion of the exterior body that is sealed by resin fusion.
[0015]
Reference numeral 2 denotes a negative electrode terminal, which uses nickel. Copper or an alloy thereof may be used for the negative electrode terminal. 3 is a positive electrode terminal, which uses aluminum. An aluminum alloy can also be used for the positive electrode terminal. The material of the terminal is not limited to these. Moreover, the part shown with the broken line among the negative electrode terminal 2 and the positive electrode terminal 3 is a part which exists between the fusion | melting part and electrode tab part of each terminal, and the distance from a terminal fusion part to an electrode tab part is 0.1 mm to 10 mm is desirable. The reason is that if the distance is 0.1 mm or less, it is difficult to control the distance between the terminal fused portion and the electrode tab portion, and a short circuit easily occurs. If the distance is 10 mm or more, the weight and volume of the battery increase and the energy density decreases. is there.
[0016]
The negative electrode plate is composed of a negative electrode current collector 4 and a negative electrode mixture layer 5, and the negative electrode current collector 4 made of copper foil has a negative electrode tab portion 4 ′ for bonding to a terminal. The negative electrode mixture layer 5 uses a carbon material capable of occluding and releasing lithium ions.
[0017]
The positive electrode plate is composed of a positive electrode current collector 6 and a positive electrode mixture layer 7, and the positive electrode current collector 6 made of aluminum foil has a tab portion 6 ′ for bonding to a terminal. The positive electrode mixture layer 7 uses a lithium-containing oxide capable of occluding and releasing lithium ions. 8 is a separator containing a non-aqueous electrolyte.
[0018]
The total thickness of the outer package and the power generation element is T. Reference numeral 9 denotes a portion which is not sealed only by pressure, and the central position of the thickness of the portion is in a region of 1 / 4T or less from the outer surface of the battery not subjected to drawing processing in the drawing depth direction. It is desirable. The same applies to the central position of the thickness of the portion 1 ′ sealed by resin fusion in the outer package 1. With such a design, a space can be provided above these portions, so that a protection circuit and lead wires can be arranged in this space. Moreover, it can also be set as the design which arrange | positions the board | substrate of the apparatus integrated using this space.
[0019]
Reference numeral 10 denotes a thermoplastic resin sheet that is chemically and electrochemically stable in the battery system. Specifically, 6 nylon, 6/6 nylon, polyvinyl chloride, thermoplastic resins such as polyolefin resins such as polyethylene and polypropylene, acid-modified polyolefin resins such as polyethylene and polypropylene modified with maleic anhydride, ionomers, EVA, EAA However, the present invention is not limited to these.
[0020]
【Example】
(Invention)
In the positive electrode, a positive electrode mixture composed of LiCoO ₂ (active material), acetylene black (conductive material) and PVDF (binder) is supported on an aluminum foil (current collector). In the negative electrode, a negative electrode mixture composed of fibrous graphite (active material), acetylene black (conductive material) and PVDF (binder) is supported on a copper foil (current collector). Both the positive electrode and the negative electrode are mixed with ethylene carbonate (EC), γ-butyrolactone (γ-BL) and polyethylene oxide (PEO) monomers, impregnated in a solution in which LiBF ₄ salt is dissolved, and the solution is irradiated by electron beam irradiation. Gelled.
[0021]
Between the positive electrode and the negative electrode, ethylene carbonate (EC), γ-butyrolactone (γ-BL), and polyethylene oxide (PEO) monomer were mixed, and a solution of LiBF ₄ salt was dissolved in polypropylene having a thickness of 20 μm. An electrode body was prepared by laminating a positive electrode, a separator, and a negative electrode by using a non-woven fabric impregnated and gelled by irradiation with ionizing radiation as an electrolyte layer / separator. However, the separator may be not only a polymer gel separator but also a nonwoven fabric or a microporous separator impregnated with an electrolyte.
[0022]
The electrode body is made of high-frequency four sides using two metal resin composites composed of a PET film with an outer surface of about 20 μm thickness, a PP film with an inner surface of about 30 μm thickness, and an aluminum foil with a core material of about 50 μm thickness. Sealed with a seal. At this time, with respect to the side where the terminal of the battery is located, a gap of about 0.5 mm is provided between the terminal welded portion and the electrode tab portion so as to cover the portion so that the terminal and the electrode tab portion are not sealed together. A thermoplastic resin sheet was provided, the electrode tab portion was pressurized to improve the adhesion between the electrode tab portion and the terminal, and only the terminal portion was high-frequency sealed to produce a battery as shown in FIGS. Maleic anhydride-modified polypropylene was used for the thermoplastic resin sheet.
[0023]
(Comparative Example 1)
An electrode body was prepared in the same manner as in the present invention, and four sides were sealed with a high frequency seal with two metal resin composites of the same material as described above. At this time, high frequency sealing was performed so that the terminal welded portion was in contact with the electrode tab portion by about 0.5 mm. In addition, a thermoplastic resin sheet was placed and pressed so as to cover the electrode tab portion that did not overlap with the portion to be sealed, thereby improving the adhesion between the electrode tab and the terminal, thereby producing a battery.
[0024]
(Comparative Example 2)
An electrode body was produced in the same manner as in the present invention, and the four sides of the two metal resin composites of the same material as above were sealed with a high frequency seal. At this time, a gap was formed between the terminal welded portion and the electrode tab portion by about 0.5 mm, and a battery was produced without placing a thermoplastic resin sheet on the electrode tab portion.
[0025]
The battery characteristics were measured by the following two methods, and a comparative study was performed. In the first test, a short circuit between the terminal and the metal resin composite material was measured (Test A), and the occurrence rate of the short circuit during the production was compared. In the second test, the terminal of the battery was lifted in a state where there was no short circuit in Test A, and only the terminal was fixed to the shaker, 10G was applied, and the subsequent impedance was measured (test B) The vibration resistance of the batteries was compared and examined. This test assumes the case where it is fixed to the device with a terminal part when it is attached to the device. The results are shown in Table 1.
[0026]
【table】

[0027]
As shown in the table, in test A, the terminal welded portion that does not include the electrode tab portion has a significantly reduced short-circuit between the terminal and the metal-resin composite as compared to the electrode tab portion that includes the electrode tab portion. Has improved dramatically. Moreover, when the battery in which the impedance became twice or more after the vibration test in Test B compared to before the test was disassembled, the joint between the terminal and the electrode tab was broken. From this result, it can be seen that both the mechanical strength and vibration resistance are improved by disposing a thermoplastic resin sheet and providing a portion that is not sealed only by pressure.
[0028]
【The invention's effect】
As described above, according to the present invention, the electrode tab is fixed at the time of sealing, the short circuit between the metal resin composite material and the terminal is prevented, the yield rate at the time of production is increased, and the vibration resistance of the joint portion is increased. Can be improved. In addition, the protective circuit and lead wires can be placed in the space where the electrode tabs are located, and since the board of the built-in equipment can be placed, the structure is advantageous in terms of energy density, and the industrial value is extremely large. It is.
[Brief description of the drawings]
FIG. 1 is a front view showing an example of a lithium secondary battery of the present invention.
FIG. 2 is a partial cross-sectional view of FIG. 1A-A portion.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Exterior body 1 'Part sealed by resin fusion | fusion 2 Negative electrode terminal 3 Positive electrode terminal 4' Negative electrode tab part 6 'Positive electrode tab part 10 Thermoplastic resin sheet

Claims

A battery using a metal-resin composite material for an exterior body, wherein at least a part is sealed by resin fusion, a positive electrode and / or a negative electrode terminal penetrates the fusion part, and a positive electrode and / or a negative electrode the electrode has an electrode tab portion of the at least one location, in a battery and the tab portion and the terminal has a joint of at least one place,
The joint portion is arranged so as to be displaced from the fusion part in the battery system to the electrode tab part side so that the terminal and the electrode tab part are not sealed together,
A terminal portion including the joining portion and different from the fused portion, and an electrode tab portion are pressed with a thermoplastic resin sheet to tightly fix the exterior body, the terminal portion, and the electrode tab portion;
A battery characterized by that.

The battery according to claim 1, wherein at least one of the exterior bodies is drawn.

The exterior body is composed of a metal resin composite material that has not been drawn and a metal resin composite material that has been drawn, and when the battery thickness is T, the center position of the terminal fused portion thickness and the The center position of the thickness of the part closely fixed with the insulating material is in a region of ¼ T or less from the outer surface of the battery not subjected to the drawing process toward the drawing depth direction. battery.

The battery according to any one of claims 1 to 3, wherein the terminal fusion part does not include an electrode tab part, and a distance between a terminal part existing between the terminal fusion part and the electrode tab is 0.1 mm to 10 mm. .