JP2005243338A

JP2005243338A - Battery with terminal

Info

Publication number: JP2005243338A
Application number: JP2004049673A
Authority: JP
Inventors: Susumu Yamanaka; 晋山中; Shinji Fujii; 慎二藤井; Toshihiko Ikehata; 敏彦池畠
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2004-02-25
Filing date: 2004-02-25
Publication date: 2005-09-08
Anticipated expiration: 2024-02-25
Also published as: JP4839574B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery coated with resin for protection against a severe environment and restraining the deterioration of discharge characteristics caused by the resin coating, related to the coin type battery put to service under the severe temperature/humidity environment of high/low temperatures and high humidity, or a severe installation environment where vibration or the like is added, and with a cathode/anode terminals firmly fixed to the surface of a battery container of a flat shape. <P>SOLUTION: An anode and a cathode using light metals as active materials are housed in a flat battery container structured of a battery case of a bottomed cylinder shape, a sealing plate and a gasket to constitute the battery. Cathode and anode plates are fitted to the sealing plate and the battery case of which at least the latter is resin-coated, and is further provided with a bottomed metal holding member at its inner bottom face for holding the cathode, so that the resin regulates the deformation of the bottom face of the battery case and a cathode ring biases the cathode toward the direction of the anode. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明は、扁平形状の電池容器に正負極の端子を取り付けた端子付き電池に関し、特に高低温の環境下、多湿の環境下での使用を前提として温度、水分等の影響を軽減するために樹脂材料にて電池ケースを被覆、固定した端子付き電池に関する。 The present invention relates to a battery with a terminal in which positive and negative terminals are attached to a flat battery container, in order to reduce the influence of temperature, moisture, etc., especially on the assumption of use in a high and low temperature environment and a humid environment. The present invention relates to a battery with a terminal in which a battery case is covered and fixed with a resin material.

コイン形、ボタン形、扁平形と称される電池容器に非水電解液を含む発電要素を収容した扁平形状の非水電解液電池（以下、コイン形電池とする）は小型薄型であるため、その特徴を生かして腕時計やキーレスエントリーなど小型化が要求される場合や、ＯＡ機器やＦＡ機器等のメモリバックアップなど長期間の使用が要求される場合に広く用いられている。最近では、コイン形電池が有する信頼性から使用用途は多岐に亘っており、過酷な環境での使用形態であっても信頼性を維持した電池が求められている。 A flat non-aqueous electrolyte battery (hereinafter referred to as a coin-type battery) in which a power generation element containing a non-aqueous electrolyte is housed in a battery container called a coin shape, a button shape, or a flat shape is small and thin. It is widely used when downsizing such as a wristwatch or keyless entry is required taking advantage of the characteristics, or when long-term use is required such as memory backup of OA equipment or FA equipment. Recently, the usage of the coin-type battery is diverse due to the reliability of the coin-type battery, and there is a demand for a battery that maintains the reliability even in a usage form in a harsh environment.

例えば、自動車のタイヤ空気圧を検出し、車両側へ検出値を送信する測定装置では、寒冷地の低温環境、制動時のブレーキ発熱による高温環境といった過酷な温度環境に曝され、さらに雨天、積雪による多湿環境にも曝されることになる。この測定装置が曝される平均的な環境は装置内部であっても温度６０℃以上、湿度７０％以上となり、特に高い速度からの急制動時には短期間ではあるが１００℃を越える高温環境となってしまう。また、前記測定装置はタイヤの内部に装着されており、少なくともタイヤ寿命に至るまでは電池交換が困難であること、タイヤ空気圧の低下は重大な事故を引き起こす要因に成りうることから、機器の作動維持に必要な放電容量を有するとともに、過酷な温度、湿度環境に耐えうる高い信頼性が要求される。 For example, a measuring device that detects the tire pressure of an automobile and transmits the detected value to the vehicle is exposed to a severe temperature environment such as a low temperature environment in a cold region or a high temperature environment due to brake heat generation during braking, and further due to rain or snow. You will also be exposed to humid environments. The average environment to which this measuring device is exposed is a temperature of 60 ° C. or higher and a humidity of 70% or higher even inside the device, and it becomes a high temperature environment exceeding 100 ° C. for a short period of time, especially during sudden braking from high speed. End up. In addition, since the measuring device is mounted inside the tire, it is difficult to replace the battery at least until the end of the tire life, and a decrease in tire air pressure can cause a serious accident. In addition to having a discharge capacity necessary for maintenance, high reliability that can withstand severe temperature and humidity environments is required.

このような要求に対して測定装置はタイヤ空気圧を検出するための制御部位、車両側に検出結果を送出するための送信部位、これらの動作用電源となる電池等の主要部分を装置ケース内に配置し、さらに前記主要部分を樹脂被覆することで過酷な温度、湿度環境への耐性を付与している。例えば特許文献１の測定装置は、制御基板、電池、アンテナを装置ケース内に配置し、ケース内をシリコン樹脂にて充填することで前記の各要素をモールドする構成を開示しており、高温、高湿の環境から主要部分を保護している。さらに樹脂充填の後にケース上端部を上蓋にて閉塞し、超音波溶着を施すことで密封固定しており、ケース内部への水分透過を抑制している。さらに測定装置に供せられる電池は、装置内部で樹脂被覆されることから電池容器に端子を溶接、固定しており、この端子が制御基板に電気的接続を担っている。また上記の環境に対応するために耐高温性を有する電解液を選択すると共に、封止及び絶縁機能を持つガスケットにも耐高温高湿性を付与している。
特開平８−１７８７８４号公報 In response to such demands, the measuring device has a control part for detecting tire air pressure, a transmission part for sending detection results to the vehicle side, and main parts such as a battery serving as an operating power source in the apparatus case. By disposing and further coating the main part with resin, resistance to severe temperature and humidity environments is imparted. For example, the measurement apparatus of Patent Document 1 discloses a configuration in which a control board, a battery, and an antenna are arranged in an apparatus case, and the above elements are molded by filling the case with silicon resin. Protects major parts from high humidity environment. Further, after the resin is filled, the upper end of the case is closed with an upper lid and sealed by ultrasonic welding to suppress moisture permeation into the case. Furthermore, since the battery used for the measuring apparatus is resin-coated inside the apparatus, a terminal is welded and fixed to the battery container, and this terminal is responsible for electrical connection to the control board. In order to cope with the above environment, an electrolyte solution having high temperature resistance is selected, and a gasket having a sealing and insulating function is also provided with high temperature high humidity resistance.
JP-A-8-178784

一般的なコイン形一次電池は、電池容器が発電要素を圧縮することによって両者の接触を確保しており、さらに前記圧縮が発電要素の内部緊迫を維持することで放電末期に至るまで安定な放電特性を発揮している。負極に軽金属、例えばリチウムを用いたコイン形電池では、放電に伴って負極のリチウムが消費されることで負極寸法が減少していく。負極で消費されたリチウムは正極に移動し、負極寸法の減少分と同等の寸法にて正極の膨張を生じる。放電反応が進行にしても発電要素の見かけ上の寸法は殆ど変化を生じておらず、内部緊迫が維持されることから安定な放電特性を示す。然し乍、高温環境下の使用では正極へのリチウムの移動が阻害され、正極の膨張が小さい場合もある。この場合には発電要素の寸法減少を招くことから内部緊迫が低下し、放電特性の低下が懸念されるだけでなく
、内部緊迫の低下に起因する放電特性の悪化により信頼性も大きく損ねることになる。特にタイヤ空気圧の測定装置では、設計上の寿命時期を迎える前に装置の機能低下を生ずることから装置自体の信頼性さえも低下させてしまう。 In general coin-type primary batteries, the battery container compresses the power generation element to ensure contact between the two, and further, the compression maintains the internal tension of the power generation element, so that stable discharge is achieved until the end of discharge. Demonstrate the characteristics. In a coin-type battery using a light metal, such as lithium, for the negative electrode, the negative electrode dimension is reduced by the consumption of lithium in the negative electrode accompanying discharge. Lithium consumed in the negative electrode moves to the positive electrode and causes the positive electrode to expand at a size equivalent to the decrease in the negative electrode size. Even if the discharge reaction proceeds, the apparent dimension of the power generation element hardly changes and the internal tension is maintained, so that stable discharge characteristics are exhibited. However, when used in a high temperature environment, the movement of lithium to the positive electrode is hindered, and the positive electrode may have a small expansion. In this case, the size of the power generation element is reduced, so internal tension is reduced, and not only is there a concern about the deterioration of the discharge characteristics, but also the reliability is greatly impaired due to the deterioration of the discharge characteristics due to the decrease in internal tension. Become. In particular, the tire pressure measuring device deteriorates the function of the device before the end of its design lifetime, and thus even reduces the reliability of the device itself.

上記のような放電に伴う内部緊迫の低下を抑制する構成として、正極ケースの底面をケース内面に向けて膨出させ、膨出部分が発電要素を付勢する構成が種々提案されている。この構成であれば、膨出部分の付勢力が内部緊迫の維持しており、放電特性の悪化は低減される。上述の如く当該測定装置に供せられるコイン形電池は、正負極の端子を装着した後に樹脂被覆する構成を採用しており、電池容器は樹脂によって変形を規制されている。この規制は容器外方向への変形だけでなく、電池容器と樹脂が接着されることから容器内方向への変形も阻止している。このため、樹脂被覆された電池容器は発電要素の厚み変動に追随した変形を呈することができず、発電要素の厚みが減少した場合には内部緊迫を維持できなくなる。このため、高温環境下での使用を前提とした電池では、内部緊迫の低下に起因する放電特性の悪化が懸念され、安定な放電特性を維持できない確立が高くなることから、信頼性を要求する用途への適用は好適ではない。してみれば、高温環境からの電池保護を目的として樹脂被覆を採用した電池は、放電特性の悪化を招きやすいという問題点を有している。 As a configuration for suppressing the decrease in internal tension accompanying the discharge as described above, various configurations have been proposed in which the bottom surface of the positive electrode case bulges toward the inner surface of the case, and the bulged portion urges the power generation element. If it is this structure, the urging | biasing force of the bulging part is maintaining internal tension, and the deterioration of a discharge characteristic is reduced. As described above, the coin-type battery used in the measuring device employs a structure in which a positive electrode and a negative electrode terminal are mounted and then resin-coated, and the battery container is restricted from being deformed by the resin. This restriction prevents not only the deformation in the outer direction of the container but also the deformation in the inner direction of the battery because the battery container and the resin are bonded. For this reason, the resin-coated battery container cannot exhibit deformation following the variation in the thickness of the power generation element, and internal tension cannot be maintained when the thickness of the power generation element decreases. For this reason, in batteries premised on use in a high temperature environment, there is a concern about deterioration of discharge characteristics due to a decrease in internal tension, and there is a high probability that stable discharge characteristics cannot be maintained, so reliability is required. It is not suitable for application. Accordingly, a battery that employs a resin coating for the purpose of protecting the battery from a high temperature environment has a problem that the discharge characteristics are likely to deteriorate.

本発明は上記問題点を解決するものであり、高低温、高湿度等の過酷な温度、湿度環境、あるいは振動等が付加される過酷な設置環境に供せられ、正負極端子が扁平形状の電池容器に表面に固着されたコイン形電池において、前記の環境からの保護を目的として樹脂被覆すると共に、樹脂被覆に起因する放電特性の悪化を抑制したコイン形電池を提供することを目的とする。 The present invention solves the above problems, and is used in a severe temperature, humidity environment such as high and low temperatures and high humidity, or a severe installation environment to which vibration is added, and the positive and negative terminals are flat. An object of the present invention is to provide a coin-type battery which is fixed on the surface of a battery container with a resin coating for the purpose of protection from the above-described environment and which suppresses deterioration of discharge characteristics due to the resin coating. .

上記目的を達成するために本発明のコイン形電池は、軽金属を活物質とする負極、正極を有底円筒形状の電池ケース及び封口板、並びにガスケットから構成される扁平形状の電池容器に収容してなり、前記封口板、電池ケースに正負極の端子板を取り付けた後、少なくとも電池ケースを樹脂被覆した構成を有しており、さらに電池ケースの内底面に正極を保持する有底、且つ金属製の保持部材を配したものである。そして、電池を被覆する樹脂が電池ケース底面の変形を規制すること、正極リングが前記正極を負極方向へ付勢することを特徴とするものである。 In order to achieve the above object, the coin-type battery of the present invention is accommodated in a flat battery container comprising a negative electrode made of light metal as an active material, a positive electrode, a bottomed cylindrical battery case and a sealing plate, and a gasket. After the positive and negative terminal plates are attached to the sealing plate and the battery case, at least the battery case is coated with resin, and the bottom and metal that holds the positive electrode on the inner bottom surface of the battery case A holding member made of metal is arranged. The resin covering the battery regulates deformation of the battery case bottom surface, and the positive electrode ring biases the positive electrode in the negative electrode direction.

上記構成によれば、金属製の保持部材が正極を負極方向へ付勢することで発電要素の厚みが減少した場合でも内部緊迫を維持している。そして正負極の接触、及び発電要素と電池容器との接触は何れも良好な状態を保ち、内部緊迫の低下に起因する放電特性の悪化が抑制される。 According to the above configuration, internal tension is maintained even when the thickness of the power generation element is reduced by the metal holding member urging the positive electrode in the negative electrode direction. The contact between the positive and negative electrodes and the contact between the power generation element and the battery container are all kept in a good state, and the deterioration of the discharge characteristics due to the decrease in internal tension is suppressed.

また、電池ケースがエポキシ樹脂等にて固定され、ケース自体の変形を規制されることから保持部材は電池ケースに対して常に面接触しており、さらに面接触の状態は発電要素の厚み変動に関係なくほぼ同等に保持される。このため、発電要素の厚みが伴う電池ケース−保持部材間における接触抵抗の上昇を生ずることはなく、接触抵抗の増加に伴う内部抵抗の上昇をも招くことはない。これに対して保持部材のみを挿入する構成では、電池容器の内圧が上昇した場合に電池ケースの変形を来たし、保持部材と電池ケースが点接触状態となってしまうことから、接触抵抗の上昇を生じてしまう。よって、本発明は電池ケースと保持部材との接触状態を良好に維持するために電池ケースの変形を規制するものであり、単に保持部材を挿入した構成とは異なる技術思想を有することは明らかである。 In addition, since the battery case is fixed with epoxy resin or the like, and the deformation of the case itself is restricted, the holding member is always in surface contact with the battery case, and the state of surface contact is due to the thickness variation of the power generation element Regardless of whether it is held almost equal. For this reason, the contact resistance between the battery case and the holding member with the thickness of the power generation element does not increase, and the internal resistance with the increase in contact resistance does not increase. On the other hand, in the configuration in which only the holding member is inserted, the battery case is deformed when the internal pressure of the battery container increases, and the holding member and the battery case are in a point contact state. It will occur. Therefore, the present invention regulates the deformation of the battery case in order to maintain a good contact state between the battery case and the holding member, and clearly has a technical idea different from the configuration in which the holding member is simply inserted. is there.

以上のことから、本発明の構成は発電要素の厚み変動に起因する放電特性の悪化を抑制しており、高温環境等の過酷な温度環境下でも安定した放電特性を維持できるものである
。 From the above, the configuration of the present invention suppresses the deterioration of the discharge characteristics due to the thickness variation of the power generation element, and can maintain the stable discharge characteristics even under a severe temperature environment such as a high temperature environment.

尚、本発明に係るコイン形は少なくとも電池ケースを樹脂被覆することでケース変形を抑えるものであるが、電池の使用環境に応じて電池全体を樹脂被覆することで前記環境による電池への影響を抑えられ、電池の信頼性を一層高めるものである。コイン形電池の封止に供せられる樹脂材料には、絶縁性を有することに加えて種々の因子を考慮して選択される。特に電池を含む機器の使用が想定される温度条件に合わせた選択が必要となり、高湿度が想定される条件では水分の透過性も重要な選択因子となる。さらに電池ケース底面における変形を規制することから樹脂材料の硬度も選択因子となり、併せて機器へ電池を装着した後に樹脂被覆を実施する構成では、樹脂材料の流動性、被覆時の樹脂温度等も考慮する必要がある。従って、樹脂材料に求められる要件を判断するとエポキシ樹脂の選定が好適と判断される。 Incidentally, the coin shape according to the present invention suppresses deformation of the case by at least covering the battery case with a resin, but the influence of the environment on the battery by covering the entire battery with a resin according to the usage environment of the battery. It is suppressed and the reliability of the battery is further enhanced. The resin material used for sealing the coin-type battery is selected in consideration of various factors in addition to having insulating properties. In particular, it is necessary to make a selection in accordance with a temperature condition in which a device including a battery is assumed to be used. Under conditions where high humidity is assumed, moisture permeability is an important selection factor. Furthermore, since the deformation at the bottom of the battery case is regulated, the hardness of the resin material is also a selection factor. In addition, in the configuration in which the resin coating is performed after the battery is mounted on the device, the fluidity of the resin material, the resin temperature at the time of coating, etc. It is necessary to consider. Therefore, judging the requirements required for the resin material, it is judged that the selection of the epoxy resin is preferable.

さらに本発明の封口板は、電池ケースと逆向きの有底円筒形の開口部にフランジ部を有し、フランジ部の先端部分に円筒方向への延出部とその折り返し部を形成してなり、前記電池ケースの開口端部を内方に折り返してカシメ封口するものである。この構成によれば、電池内圧の上昇が生じたい場合でもカシメ封口が施された部位に内圧上昇に起因する封口板の変形が遡及せず、耐漏液性を大幅に向上させることができる。このため、高温等の過酷な温度環境に曝される電池であっても漏液の発生を確実に抑制し、電池の信頼性を高めるものであり、本発明に係る保持部材、電池ケースの構成による効果を一層高めるものである。 Furthermore, the sealing plate of the present invention has a flange portion at the bottomed cylindrical opening opposite to the battery case, and has a cylindrical extension portion and a folded portion formed at the tip portion of the flange portion. The open end of the battery case is folded inward to seal it. According to this configuration, even when it is desired to increase the battery internal pressure, the deformation of the sealing plate due to the increase in the internal pressure does not retroactively occur at the site where the caulking seal is applied, and the leakage resistance can be greatly improved. For this reason, even if the battery is exposed to a severe temperature environment such as a high temperature, the occurrence of liquid leakage is reliably suppressed and the reliability of the battery is improved. The effect by is further enhanced.

以上の通り本発明は、過酷な温湿度環境、あるいは設置環境に供せられる端子付きのコイン形電池において、発電要素の厚み変動、及び内圧上昇に起因する放電特性の悪化を抑制し、電池の信頼性を高める効果を奏するものである。 As described above, the present invention suppresses deterioration of discharge characteristics due to fluctuations in the thickness of the power generation element and increase in internal pressure in a coin-type battery with a terminal that is used in a severe temperature and humidity environment or an installation environment. It has the effect of improving reliability.

以下、添付図面を参照して本発明の実施形態について説明し、本発明の理解に供する。図１の断面図は、本実施形態に係る端子付きコイン形電池の構造を示している。電池ケース１、封口板２を含む電池容器には、正極６と負極４がセパレータ５を介して対向配置されており、電解液が充填されている。電池ケース１の開口部は、ガスケット３を介して封口板２を配しており、カシメ封口を施すことでコイン形状の外観を呈する電池に構成されている。 Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention. The cross-sectional view of FIG. 1 shows the structure of a coin-type battery with a terminal according to this embodiment. In the battery container including the battery case 1 and the sealing plate 2, the positive electrode 6 and the negative electrode 4 are disposed to face each other with the separator 5 interposed therebetween, and are filled with an electrolytic solution. The opening part of the battery case 1 is provided with a sealing plate 2 via a gasket 3, and is configured as a battery exhibiting a coin-shaped appearance by applying a caulking seal.

保持部材７はカップ状に形成されており、本実施形態では後述するように底面の中央部が電池ケース側に膨出した形状としている。この保持部材７は底面及び立ち上がり部分にて正極６の底面及び周面を保持しており、底面との間で電気的接続を確保している。さらに保持部材７はカシメ封口時に膨出部位を押圧することで正極６を負極４の方向へ付勢するものである。また、カシメ封口時に保持部材７の底面は電池ケース１に押圧され、両者の電気的接続を確実にしている。 The holding member 7 is formed in a cup shape, and in the present embodiment, the center portion of the bottom surface is bulged toward the battery case side as will be described later. The holding member 7 holds the bottom surface and the peripheral surface of the positive electrode 6 at the bottom surface and the rising portion, and ensures electrical connection with the bottom surface. Furthermore, the holding member 7 urges the positive electrode 6 in the direction of the negative electrode 4 by pressing the bulging portion when the caulking is sealed. Further, the bottom surface of the holding member 7 is pressed against the battery case 1 at the time of caulking and sealing to ensure the electrical connection between them.

さらに電池ケース１、及び封口板２の表面には各々正極端子１０１、負極端子２０１が固着されている。これら端子は何れも溶接により固着されており、コイン形状に電池を作成した後に溶接を施したものであり、さらに端子装着後にコイン形電池はエポキシ樹脂３００にて樹脂被覆される。この樹脂被覆により電池ケース１の底面における変形が規制されており、前記底面が電池容器の内圧上昇や発電要素の厚み変動による変形を抑止している。 Further, a positive electrode terminal 101 and a negative electrode terminal 201 are fixed to the surfaces of the battery case 1 and the sealing plate 2, respectively. All of these terminals are fixed by welding, and the battery is made in a coin shape and then welded. Further, the coin-type battery is coated with an epoxy resin 300 after the terminals are mounted. Due to this resin coating, deformation at the bottom surface of the battery case 1 is restricted, and the bottom surface suppresses deformation due to an increase in the internal pressure of the battery container and fluctuations in the thickness of the power generation element.

本実施形態における封口板２は電池ケース１と逆向きの有底円筒形の開口部にフランジ
部９を有しており、さらにフランジ部９の先端部分に円筒方向への延出部１０とその折り返し部１１を形成している。一方、電池ケース１は底部周囲に少なくとも延出部１０の内径より小さい外径で段差部１２を形成している。そして、ガスケット３が段差部１２から延出された外周底部１５の内底面上及び折り返し部１１の先端上からフランジ部９上に圧縮されるようにカシメ加工を施している。電池内圧の上昇が生じた場合、電池ケース１の変形は段差部１２によって変形圧力を分散し、封口板２の変形はフランジ部９を挟む両縁にて変形圧力を分散する。これら変形圧力の分散は、封口部分の変形を抑制し、高温度雰囲気下など過酷な使用条件下においても優れた耐漏液性を得ることができる。 The sealing plate 2 in the present embodiment has a flange portion 9 in a bottomed cylindrical opening opposite to the battery case 1, and further, a cylindrical extension portion 10 at the tip portion of the flange portion 9 and the flange portion 9. A folded portion 11 is formed. On the other hand, the battery case 1 has a stepped portion 12 having an outer diameter smaller than the inner diameter of the extending portion 10 around the bottom portion. The gasket 3 is crimped so as to be compressed onto the flange portion 9 from the inner bottom surface of the outer peripheral bottom portion 15 extending from the stepped portion 12 and from the top end of the folded portion 11. When the battery internal pressure rises, the deformation of the battery case 1 disperses the deformation pressure by the step portion 12, and the deformation of the sealing plate 2 disperses the deformation pressure at both edges sandwiching the flange portion 9. Dispersion of these deformation pressures suppresses deformation of the sealing portion, and excellent leakage resistance can be obtained even under severe use conditions such as in a high temperature atmosphere.

本発明は保持部材７にて正極６を負極４の方向に付勢する構成を採用している。このため保持部材７は予め底部の中心、もしくは周縁部が膨出した形状に加工されている。図１に示す本実施形態では、カップ状の保持部材７において底面の中央部が周縁部に対して膨出した形状としており、この形状による生ずるバネ性にて正極７を負極４の方向に付勢するものである。図１はミクロ的な視点に基づき保持部材の形状を俯瞰しており、電池ケース１と保持部材７の中央部が接した状態としている。しかし、実際のコイン形電池では電池構成時の加圧力により保持部材７の底面全体が電池ケース１に接する状態となり、接触抵抗の上昇を招くことはない。また、上記のカップ状の保持部材７に代えて断面が略Ｌ字状の保持部材を用い、この保持部材の底面を周縁部に対して膨出した形状とすることで保持部材にバネ性を付与することが可能であり、本発明による効果が得られるものである。本発明に係る保持部材７は、電池容器の内部空間の高さ、すなわち容器内の厚みに対して５〜４０％の値で膨出した形状とするのが好ましい。図１における保持部材７は上述のように中央部が周縁部に対して膨出した形状（以下、凸形状という）を採用しており、図１に示す通り膨出部のバネ性により正極を負極方向に付勢している。さらに前記の凸形状に代えて周縁部が中央部に対して膨出した形状（以下、凹形状という）としても良い。この凹形状を採用した保持部材では、主に保持部材の周縁部が電池ケースへ接することになり、保持部材の中央部におけるバネ性により正極を付勢することになる。 The present invention employs a configuration in which the holding member 7 biases the positive electrode 6 in the direction of the negative electrode 4. For this reason, the holding member 7 is processed in advance into a shape in which the center of the bottom portion or the peripheral portion swells. In the present embodiment shown in FIG. 1, the cup-shaped holding member 7 has a shape in which the central portion of the bottom surface bulges with respect to the peripheral portion, and the positive electrode 7 is attached in the direction of the negative electrode 4 due to the spring property generated by this shape. It is a force. FIG. 1 is a bird's-eye view of the shape of the holding member based on a microscopic viewpoint, in which the battery case 1 and the central portion of the holding member 7 are in contact with each other. However, in an actual coin-type battery, the entire bottom surface of the holding member 7 is in contact with the battery case 1 due to the applied pressure during battery construction, and the contact resistance is not increased. Further, instead of the cup-shaped holding member 7 described above, a holding member having a substantially L-shaped cross section is used, and the holding member is made to have a spring property by making the bottom surface of the holding member bulge with respect to the peripheral portion. The effect of the present invention can be obtained. The holding member 7 according to the present invention preferably has a shape bulging at a value of 5 to 40% with respect to the height of the internal space of the battery container, that is, the thickness inside the container. The holding member 7 in FIG. 1 adopts a shape in which the central portion bulges with respect to the peripheral portion as described above (hereinafter referred to as a convex shape), and as shown in FIG. Energized in the negative direction. Furthermore, it is good also as a shape (henceforth a concave shape) which the peripheral part bulged with respect to the center part instead of the said convex shape. In the holding member adopting this concave shape, the peripheral edge portion of the holding member mainly comes into contact with the battery case, and the positive electrode is biased by the spring property at the central portion of the holding member.

保持部材は膨出部の形状を考慮する必要がある。本実施形態の保持部材の形状は周縁部の包含する平面に対する膨出部の頂部高さで規定しており、好ましくは前述した容器内の厚みに対する比率（以下、膨出比率）が５〜４０％となるように保持部材の形状を決定している。 The holding member needs to consider the shape of the bulging portion. The shape of the holding member of the present embodiment is defined by the height of the top of the bulging portion relative to the plane encompassed by the peripheral portion, and preferably the ratio to the thickness in the container described above (hereinafter referred to as the bulging ratio) is 5 to 40. The shape of the holding member is determined to be%.

この時、電池容器の厚みより好ましい膨出比率の範囲は異なるが、一般的な電池容器の厚みであれば上記の範囲とすることで本発明による効果が確実に奏されるものである。膨出比率が５％未満であると保持部材による正極への付勢が不十分になる虞がある。この内部緊迫の不足は放電特性を悪化させる主因となり得ることから膨出比率を５％以上に設定するのが好適である。一方、膨出比率が４０％を越えると保持部材の弾性力が高まり、正極への押圧力が過大となる。このため、正極の変形を招く虞があるだけでなく、さらに保持部材の変形も不十分となり、電池ケースと保持部材との接触面積が減少した状態となり、接触抵抗の上昇も招いてしまう。さらに保持部材の弾性力によって封口板に容器外方への応力が付加されることから、カシメ強度の低下を生じせしめ、耐漏液性を大きく悪化させるものである。 At this time, the range of the preferred bulging ratio is different from the thickness of the battery container, but if the thickness is a general battery container, the effect according to the present invention is surely achieved by setting the above range. If the bulging ratio is less than 5%, the urging of the positive electrode by the holding member may be insufficient. Since the lack of internal tension can be a main cause of deterioration of the discharge characteristics, it is preferable to set the bulging ratio to 5% or more. On the other hand, when the bulging ratio exceeds 40%, the elastic force of the holding member increases, and the pressing force to the positive electrode becomes excessive. For this reason, there is a risk that the positive electrode may be deformed, and further, the holding member is not sufficiently deformed, the contact area between the battery case and the holding member is reduced, and the contact resistance is also increased. Furthermore, since the outward stress of the container is applied to the sealing plate by the elastic force of the holding member, the caulking strength is lowered and the liquid leakage resistance is greatly deteriorated.

以上の通り本実施形態におけるコイン形電池は、保持部材にて正極を負極方向に付勢することで内部緊迫を維持しており、安定した放電特性を持つものである。 As described above, the coin-type battery according to the present embodiment maintains the internal tension by urging the positive electrode in the negative electrode direction with the holding member, and has stable discharge characteristics.

以下、本発明の実施例について説明する。尚、本実施例では、正極にフッ化黒鉛を、負極にリチウム金属、そして電解液に有機電解液を用いると共に上述した本発明の実施形態に係るコイン形電池を作製し、評価を実施した。 Examples of the present invention will be described below. In the present example, graphite fluoride was used for the positive electrode, lithium metal was used for the negative electrode, and an organic electrolytic solution was used for the electrolytic solution, and a coin-type battery according to the above-described embodiment of the present invention was manufactured and evaluated.

（電池の作製）
本実施例では電池ケース１及び封口板２として厚み０．５ｍｍのステンレス鋼板（ＳＵＳ４３０）を用い、各々の形状にプレス加工にて作製した。さらに両者を絶縁保持するガスケット３はポリフェニレンサルフィド樹脂を射出成型にて作製している。これら電池ケース１、封口板２は予めガスケット３に接する部位に封止剤を塗布、乾燥することで電池作製後における耐漏液性を向上させている。また、保持部材７は電池容器と同様にステンレス鋼板（ＳＵＳ４３０）を採用し、プレス加工によりカップ状と成型した。この時、保持部材７は図１に示す通り底面の中央部を電池ケース側に膨出させた構成としており、本実施形態における凸形状としている。膨出比率を５％になるように成型している。作製された保持部材７は後述する過程で作製した正極６を保持すると共に、カシメ封口時に膨出部位を押圧することで正極６を負極４の方向へ付勢するものである。 (Production of battery)
In this example, a stainless steel plate (SUS430) having a thickness of 0.5 mm was used as the battery case 1 and the sealing plate 2, and each shape was produced by press working. Further, the gasket 3 for insulating and holding both is made of polyphenylene sulfide resin by injection molding. In the battery case 1 and the sealing plate 2, the leakage resistance after the battery is manufactured is improved by previously applying a sealing agent to a portion in contact with the gasket 3 and drying. The holding member 7 was made of a stainless steel plate (SUS430) in the same manner as the battery container, and was molded into a cup shape by press working. At this time, as shown in FIG. 1, the holding member 7 has a configuration in which the central portion of the bottom surface is bulged toward the battery case, and has a convex shape in the present embodiment. Molded so that the bulging ratio is 5%. The produced holding member 7 holds the positive electrode 6 produced in the process to be described later, and urges the positive electrode 6 in the direction of the negative electrode 4 by pressing the bulging portion when the caulking is sealed.

一方、発電要素である正極６は二酸化マンガン、導電剤及び結着剤の混合粉末を加圧成型しペレット状にしてある。より詳細には二酸化マンガン、導電剤であるカーボン及び結着剤であるフッ素樹脂粉末を混合し、ペレット状に加圧成型した後、２００℃にて１２時間乾燥している。セパレータ５は、ポリブチレンテレフタレートの不織布を正極より大なる径に打ち抜くことで作製される。負極４は金属リチウムであり、フープ状の金属リチウムを円形に打ち抜いた後、図１に示す形状を有する封口板２の中央内面に圧着される。電池ケース１に発電要素を各々配した後、カシメ封口することによりコイン形電池を作製した。得られた電池は直径２４．５ｍｍ、厚さ５．０ｍｍであり、ＢＲ２４５０（ＪＩＳ規格）に相当するものであり、本発明に係る電池Ａとする。また、本実施例では膨出比率が５％に設定された凹形状の保持部材７を作製し、他の構成を電池Ａと同様にした電池ａも作製した。 On the other hand, the positive electrode 6 which is a power generation element is formed into a pellet by press-molding a mixed powder of manganese dioxide, a conductive agent and a binder. More specifically, manganese dioxide, carbon as a conductive agent, and fluororesin powder as a binder are mixed, pressed into a pellet, and then dried at 200 ° C. for 12 hours. The separator 5 is produced by punching a non-woven fabric of polybutylene terephthalate to a diameter larger than that of the positive electrode. The negative electrode 4 is metallic lithium. After punching out the hoop-shaped metallic lithium into a circular shape, the negative electrode 4 is pressed against the center inner surface of the sealing plate 2 having the shape shown in FIG. After each of the power generation elements was arranged in the battery case 1, a coin-type battery was produced by caulking and sealing. The obtained battery has a diameter of 24.5 mm and a thickness of 5.0 mm, corresponds to BR2450 (JIS standard), and is designated as battery A according to the present invention. In this example, a concave holding member 7 having a bulging ratio set to 5% was manufactured, and a battery a having the same configuration as that of the battery A was also manufactured.

さらに本実施例は保持部材７の形状が異なる複数の電池を作製した。保持部材７として、膨出比率が３〜５０％に設定された凸形状、及び凹形状のものを作製している。そして、これら保持部材を用いて他の構成は電池Ａ、電池ａと同様にした電池Ｂ〜電池Ｅ、並びに電池ｂ〜電池ｅを作製した。また、膨出部位が未形成の保持部材を用いた電池も作製した。これを比較電池１とする。さらに保持部材を使用せず、電池ケース１の底面を容器内面側に膨出させた構成を有し、封口板及び発電要素の構成は電池Ａと同様にした比較電池２も作製した。これら作製した電池における保持部材の膨出比率は表１に示す通りである。 Further, in this example, a plurality of batteries having different holding member 7 shapes were produced. As the holding member 7, a convex shape and a concave shape whose bulge ratio is set to 3 to 50% are manufactured. Then, using these holding members, batteries B to battery E, and batteries b to battery e were manufactured in the same manner as battery A and battery a. In addition, a battery using a holding member in which the bulging site was not formed was also produced. This is referred to as comparative battery 1. Furthermore, a comparative battery 2 having a configuration in which the bottom surface of the battery case 1 was expanded toward the inner surface of the container without using a holding member, and the configuration of the sealing plate and the power generation element was the same as that of the battery A was also produced. Table 1 shows the bulging ratio of the holding members in these batteries.

（電池の評価）
電池の評価は上記の如く作製した各々の電池について高温環境下での放電容量を測定することで実施した。さらに前記評価において作製した電池をエポキシ樹脂で被覆した状態、及び未被覆の状態で放電容量の測定を実施した。放電容量の測定は、６０℃の環境下に樹脂被覆された供試電池、未被覆の供試電池を曝した状態において、放電電流１３ｍＡ、放電時間１０ｍｓの放電条件と放電電流０．０１ｍＡ、放電時間６０ｓの放電条件を繰り返した。電池の放電電圧が２．０Ｖに達した時点で放電を終了した。終了時点に至るまでの容量は表１に示す通りである。尚、本実施例における電池は設計上の放電容量を５５０ｍＡｈとしている。 (Battery evaluation)
The battery was evaluated by measuring the discharge capacity in a high temperature environment for each battery produced as described above. Further, the discharge capacity was measured in a state where the battery produced in the evaluation was coated with an epoxy resin and an uncoated state. The discharge capacity was measured with a discharge current of 13 mA, a discharge time of 10 ms, a discharge current of 0.01 mA, and a discharge current in a state where a test battery coated with resin and an uncoated test battery were exposed to an environment of 60 ° C. The discharge condition for 60 seconds was repeated. The discharge was terminated when the discharge voltage of the battery reached 2.0V. The capacity up to the end point is as shown in Table 1. The battery in this example has a designed discharge capacity of 550 mAh.

実施結果を表１に示す。樹脂が未被覆の場合、放電容量は比較電池１を除いて約５５０ｍＡｈであり、安定した放電特性が得られている。比較電池１は内部緊迫の不足による内部抵抗の上昇を生じており、４８０ｍＡｈ近辺まで放電した際に１３ｍＡ放電を行うと２．０Ｖを下回った。 The results are shown in Table 1. When the resin is uncoated, the discharge capacity is about 550 mAh except for the comparative battery 1, and stable discharge characteristics are obtained. The comparative battery 1 had an increase in internal resistance due to lack of internal tension, and when discharged to around 480 mAh, it was less than 2.0 V when 13 mA discharge was performed.

樹脂被覆した場合、電池Ａ、並びに電池Ｃ〜Ｅでは約５５０ｍＡｈの放電容量を得ることができた。しかし、比較電池１は４２０ｍＡｈ、そして比較電池２は４３５ｍＡｈの放電容量しか得られず、設計上の放電容量を得られなかった。これらの原因は何れも未被覆状態の比較電池１と同様に内部緊迫の減少に起因するものである。比較電池１は樹脂被覆無しと同様の事由であり、保持部材による内部緊迫が得られないために放電容量の低下を招いたものである。比較電池２では、樹脂が未被覆の状態では設計通りの放電容量が得られたが樹脂被覆の状態では容量が得られなかった。この原因は電池ケースが樹脂により固定され、発電要素の厚み減少に応じた電池ケースの変形が得られず、且つ保持部材による内部緊迫の維持もできないためである。一方、電池Ｂ、電池ｂは５１３〜５２０ｍＡｈであった。これは他の電池に比べて保持部材の膨出量が小さいとから、放電末期において正極への付勢が不十分となり、発電要素の厚み減少を補うための変形量が確保できなかったものである。しかし、比較電池１，２に比べて放電容量も改善されており、且つ放電末期に至るまでの期間においては正極への付勢が十分に確保され、他の電池と同等の放電特性を有することから、放電末期に至るまでの使用を前提としない機器では本発明の効果が発揮されるものである。 When the resin was coated, the battery A and the batteries C to E were able to obtain a discharge capacity of about 550 mAh. However, the comparative battery 1 could only obtain a discharge capacity of 420 mAh, and the comparative battery 2 could only obtain a discharge capacity of 435 mAh, and the designed discharge capacity could not be obtained. These causes are caused by a decrease in internal tension as in the uncoated comparative battery 1. The comparative battery 1 has the same reason as the case without the resin coating, and the internal tension by the holding member cannot be obtained, so that the discharge capacity is reduced. In the comparative battery 2, a discharge capacity as designed was obtained when the resin was not coated, but no capacity was obtained when the resin was coated. This is because the battery case is fixed with resin, the deformation of the battery case according to the thickness reduction of the power generation element cannot be obtained, and the internal tension cannot be maintained by the holding member. On the other hand, the battery B and the battery b were 513 to 520 mAh. This is because the bulging amount of the holding member is small compared to other batteries, so the bias to the positive electrode is insufficient at the end of discharge, and the deformation amount to compensate for the decrease in thickness of the power generation element could not be secured. is there. However, the discharge capacity is improved as compared with the comparative batteries 1 and 2, and the positive electrode is sufficiently energized in the period up to the end of discharge, and has the same discharge characteristics as other batteries. Therefore, the effect of the present invention is exhibited in a device that does not assume use until the end of discharge.

上記の如く本発明に係る構成を採用した電池では、高温環境下での使用でも安定した放電特性をもつことは明らかである。しかし、保持部材の膨出量が大きくなる電池Ｅ、電池ｅでは、電池の組み立てに際して保持部材からの弾性力によりカシメ封口の不良を生じた電池が発生した。この不良はカシメ封口を行う際に保持部材からの弾性力が過大となり、封口板を上方へ押し上げたことに起因するものであり、コイン電池の生産性を重要視する場合には４０％以下の設定が好ましい。以上のことから、本発明における特に好ましい範囲は膨出比率５〜４０％であり、この範囲にある保持部材を用いることでカシメ不良に起因する生産性の低下を抑制すると同時に、内部緊迫が低下する放電条件でも放電末期に至るまで特に安定した放電特性を有する信頼性の高いコイン形電池を実現できるものである。尚、本実施例においてエポキシ樹脂による被覆を行ったが、この被覆に代えて、堅固な板状の樹脂に電池ケースの底面を接着する構成であっても本発明と同様の効果を示すものである。 As described above, it is obvious that the battery adopting the configuration according to the present invention has stable discharge characteristics even when used in a high temperature environment. However, in the battery E and the battery e in which the bulging amount of the holding member is large, a battery in which the caulking seal is defective due to the elastic force from the holding member during battery assembly occurred. This defect is caused by excessive elastic force from the holding member when the caulking sealing is performed, and the sealing plate is pushed upward. When the productivity of the coin battery is regarded as important, it is 40% or less. Setting is preferred. From the above, the particularly preferred range in the present invention is a bulging ratio of 5 to 40%, and by using the holding member in this range, it is possible to suppress the decrease in productivity due to the caulking failure and at the same time the internal strain is reduced. It is possible to realize a highly reliable coin-type battery having particularly stable discharge characteristics until the end of discharge even under the discharge conditions. In this example, the coating with the epoxy resin was performed, but instead of this coating, the same effect as the present invention can be obtained even when the bottom surface of the battery case is adhered to a rigid plate-shaped resin. is there.

本発明は、高温環境等の内部緊迫が低下する使用条件であっても安定した放電特性を有しており、過酷な環境で使用される機器の電源としての活用が好適である。 The present invention has stable discharge characteristics even under use conditions where internal tension such as a high temperature environment is reduced, and is suitable for use as a power source for equipment used in harsh environments.

本発明の実施形態おけるコイン形電池の断面構造を示す模式図The schematic diagram which shows the cross-section of the coin-type battery in embodiment of this invention

符号の説明Explanation of symbols

１電池ケース
２封口板
３ガスケット
４負極
５セパレータ
６正極
７保持部材
９フランジ部
１０延出部
１１折り返し部 DESCRIPTION OF SYMBOLS 1 Battery case 2 Sealing plate 3 Gasket 4 Negative electrode 5 Separator 6 Positive electrode 7 Holding member 9 Flange part 10 Extension part 11 Folding part

Claims

軽金属を活物質とする負極、正極を有底円筒形状の電池ケース及び封口板、並びにガスケットから構成される扁平形状の電池容器に収容してなり、前記封口板、電池ケースに正負極の端子板を取り付け、少なくとも電池ケースを樹脂被覆した端子付き電池であって、前記電池ケースは前記正極を保持する有底、且つ金属製の保持部材を内底面に配しており、前記樹脂が電池ケース底面の変形を規制すると共に、前記正極リングが前記正極を負極方向へ付勢することを特徴とする端子付き電池。 A negative electrode using a light metal as an active material, and a positive electrode are accommodated in a flat battery container including a bottomed cylindrical battery case and a sealing plate, and a gasket, and the positive and negative terminal plates are connected to the sealing plate and the battery case. A battery with a terminal in which at least the battery case is coated with a resin, the battery case having a bottom for holding the positive electrode and a metal holding member on the inner bottom surface, and the resin is on the bottom surface of the battery case And the positive electrode ring biases the positive electrode in the negative electrode direction.

封口板は、電池ケースと逆向きの有底円筒形の開口部にフランジ部を有し、フランジ部の先端部分に円筒方向への延出部とその折り返し部とを形成してなり、前記電池ケースの開口端部を内方に折り返してカシメ封口する請求項１記載の端子付き電池。 The sealing plate has a flange portion in a bottomed cylindrical opening opposite to the battery case, and has a cylindrical extension portion and a folded portion at a tip portion of the flange portion, and the battery The battery with a terminal according to claim 1, wherein the opening end of the case is folded inward to be caulked and sealed.