JP2004213951A

JP2004213951A - Lead-acid battery

Info

Publication number: JP2004213951A
Application number: JP2002379877A
Authority: JP
Inventors: Toshio Matsushima; 敏雄松島; Tomonobu Tsujikawa; 知伸辻川
Original assignee: NTT Power and Building Facilities Inc
Current assignee: NTT Power and Building Facilities Inc
Priority date: 2002-12-27
Filing date: 2002-12-27
Publication date: 2004-07-29

Abstract

<P>PROBLEM TO BE SOLVED: To secure high reliability without causing battery jar breakage or the like even if a lead-acid battery is used over a long time. <P>SOLUTION: A bone part 1 is disposed inside a collector. The collector is manufactured by using a lead-calcium (0.05%)-tin (1.0%)-aluminum (0.02%) alloy, and by a book-mold casting method. It is confirmed that the elongation of the collector generated in using the sealed lead-acid battery over a long time is absorbed, and 70% of its capacity is kept. That is to say, the service life thereof is improved by 20% as compared with a sealed lead-acid battery using a collector of a conventional technique. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、複数枚の正極板と負極板とをセパレータを介して組み立てた極板群が硫酸と共に電槽に収納された鉛蓄電池に関する。
【０００２】
【従来の技術】
シール鉛蓄電池は、複数枚の正極板と負極板とをセパレータを介して組み立てた極板群が硫酸と共に電槽に収納されることで構成される。正・負極板は、障子の桟部のような格子状の開口部を有する集電体に、電池反応に関わる活物質が塗り込まれて形成されている。集電体の役割は、反応に関与する活物質の保持と充放電に伴う電流の通路の確保とにある。
【０００３】
図７（ａ）は、従来技術による鉛蓄電池の集電体の構造例を示す平面図であり、同図（ｂ）は、その断面図である。図７（ａ）において、集電体全体の補強を兼ねて、骨部１が集電体の外周部を構成し、その内部に縦方向に延びる縦桟部２、横方向に延びる横桟部３とが配置されている。骨部１と縦桟部２、横桟部３との太さは、図７（ｂ）に示すように、前者の方が大きくなっている。電極は、この様な集電体に活物質を塗布することで構成されている。
【０００４】
一方、正極においては、通常、予備電源として使用されると、常時、充電反応下に置かれるため、集電体は、電気化学的な酸化を受ける。このため、集電体表面が酸化し、長期間使用した場合には、活物質の保持が困難になり、電池としての機能が不可能となる。このため、集電体に使用される合金の検討が行われ、シール鉛蓄電池では、集電体に、鉛とカルシウムとスズの鉛合金が使用されている（例えば、非特許文献１参照）。
【０００５】
【特許文献１】
ＧＳＮｅｗｓｔｅｃｈｎｉｃａｌＲｅｐｏｒｔ，１９９８年６月第５７巻第１号、ｐ．１６
【０００６】
【発明が解決しようとする課題】
しかしながら、上述した従来技術による鉛蓄電池では、カルシウムとスズを含有する鉛合金を用いて鋳造法で集電体を作製しているため、合金内に「粒」が形成され、各「粒」間には界面が形成される。集電体は、電池の使用中、充電状態にあるので、酸化を受けるが、この酸化によって上記「粒」の界面で酸化（腐食）が進行しやすい。このため、粒界に酸化による生成物である硫酸鉛が生成し、集電体合金全体に伸びが生じ、活物質の保持が困難になり、放電時間の短縮や最悪、放電不可能という事態に陥る。集電体の外周部方向への伸びは、１０％にも達することがあり、このため、極板群を収容する電槽が伸びた正極板によって圧迫されて破損し、電解液が漏れたり、さらに、漏れた電解液による周囲の腐食・火災等の２次災害の恐れがあった。
【０００７】
この発明は上述した事情に鑑みてなされたもので、長期間にわたって使用しても電槽破壊等を発生することなく、高い信頼性を確保することができる鉛蓄電池を提供することを目的とする。
【０００８】
【課題を解決するための手段】
上述した問題点を解決するために、請求項１記載の発明では、正極板と負極板を、骨部と桟部とによって交互に組み合わせた集電体の全面に電極活物質が塗布されて極板が形成された鉛蓄電池であって、前記骨部を前記集電体の内側に配置したことを特徴とする。
【０００９】
また、請求項２記載の発明では、請求項１記載の鉛蓄電池において、前記骨部は、前記集電体の内側に方形状に形成されていることを特徴とする。
【００１０】
また、請求項３記載の発明では、請求項１記載の鉛蓄電池において、前記骨部は、前記集電体の内側に放射状に形成されていることを特徴とする。
【００１１】
また、請求項４記載の発明では、請求項２記載の鉛蓄電池において、前記骨部は、少なくとも縦方向か横方向のいずれか一方の一部に、曲線状に形成された伸び吸収部を有することを特徴とする。
【００１２】
また、請求項５記載の発明では、請求項２記載の鉛蓄電池において、前記骨部は、前記集電体の内側に分割して形成され、それぞれの位置をずらして配置されていることを特徴とする。
【００１３】
また、請求項６記載の発明では、請求項１ないし５のいずれかに記載の鉛蓄電池において、前記集電体は、カルシウム（０．０４〜０．１重量％）とスズ（０．１〜２．５重量％）と、アルミニウムもしくは銀（０．００５〜０．０５重量％）とを含有する鉛合金を主成分とすることを特徴とする。
【００１４】
また、請求項７記載の発明では、請求項１ないし５のいずれかに記載の鉛蓄電池において、前記集電体を電槽内に収納した状態において、前記正極板の側部および底部と前記電槽の内壁との離隔距離が前記正極板の幅、高さ寸法の５％以下であることを特徴とする。
【００１５】
この発明では、骨部と桟部とによって正極板と負極板を交互に組み合わせ、全面に電極活物質が塗布されて極板が形成された集電体の前記骨部を前記集電体の内側に配置する。したがって、使用した際に生じる集電体の伸びが吸収され、長期間にわたって使用しても電槽破壊等を発生することなく、高い信頼性を確保することが可能となる。
【００１６】
【発明の実施の形態】
以下、図面を用いて本発明の実施の形態を説明する。
【００１７】
Ａ．第１実施形態
図１（ａ）は、本発明の第１実施形態によるシール鉛蓄電池の集電体の構成を示す平面図であり、同図（ｂ）は、その断面図である。図１において、図７に示される従来の集電体構造を基本として、縦桟部２、横桟部３より断面積が大きい骨部１の位置を集電体の最外部から内側の位置に移動させた構造を有する。
【００１８】
次に、図１（ａ），（ｂ）に示す構造の集電体によって極板作製と電池の組み立てを行なった場合の電池特性に対する効果について説明する。具体的には、鉛−カルシウム（０．０５％）−スズ（１．０％）−アルミニウム（０．０２％）合金を用い、ブックモールド鋳造法によって集電体を製造した。作製した集電体は、タブ４を含まない有効部の寸法が１３×１０ｃｍ（高さ×幅）で、厚みは骨部１で４ｍｍである。鋳造法による場合、鋳造体の全体寸法や集電体の骨のサイズは、鋳型全体の彫り込みで決定されるので、鋳型の調整で本第１実施形態による構造を有する集電体の製造が容易に行なえた。また、比較用として、同様の方法で、図７（ａ），（ｂ）に示す従来技術による集電体も作製した。
【００１９】
このような集電体に活物質を塗布して正極板を作製し、正極板４枚／負極板５枚からなるシール鉛蓄電池を組み立てた。組み立てたシール鉛蓄電池は、定格電圧２Ｖ、１０時間率定格容量は３０Ａｈである。これらのシール鉛蓄電池について、高温下で連続充電を行ない、容量変化や試験終了後の極板の伸び状況の確認を行った。
【００２０】

【００２１】
この結果、図６に示すように、従来技術による集電体を使用したシール鉛蓄電池では、６０℃環境下で約１０ヶ月放置した後の容量が初期の７０％以下まで低下したのに対し、本第１実施形態によるシール鉛蓄電池では、１２ヶ月後にも７０％の容量が保たれていることが確認された。すなわち、本第１実施形態では、従来技術の集電体を使用したシール鉛蓄電池に比べて、寿命が２０％改善されていることが分かる。また、上記期間終了後のシール鉛蓄電池を解体し、正極板の寸法変化を測定した結果、以下のように本第１実施形態によるシール鉛蓄電池における伸びが抑制されていた。
【００２２】
従来品：９％（６０℃、１０ヶ月後）
第１実施形態：５％（６０℃、１２ヶ月後）
【００２３】
上述したように、本第１実施形態によれば、長期にわたってシール鉛蓄電池を使用した際に生じる集電体の伸びの吸収が図られ、電槽破壊やこれによる電解液の漏れといった二次的な問題の発生も抑えることができる。この結果、電池寿命が延伸されると共に、正極板の伸び量も抑制され、電槽内壁との離隔距離としては５％程度で十分であることが分かる。すなわち、同一サイズの集電体を使用した場合、電槽の小型化が可能ということになり、電池のコンパクト化を図ることができる。
【００２４】
Ｂ．第２実施形態
次に、図２は、本発明の第２実施形態によるシール鉛蓄電池の集電体の構成を示す平面図である。図において、集電体内における骨部１は、タブ４の部分から周辺部に向かって延びた、いわゆるラジアル構造を有する。従来技術による集電体は、骨部１の集電体上部と左端に位置する部分が最も外側に有り、その他の部分は、集電体の末端まで延びていた。これに対して、本第２実施形態では、集電体の内側の部分に全ての骨部１が配置されるようになっている。
【００２５】
Ｃ．第３実施形態
次に、図３（ａ）は、本発明の第３実施形態によるシール鉛蓄電池の集電体の構成を示す平面図であり、同図（ｂ）は、その断面図である。本第３実施形態では、図示するように、前述した第１実施形態による集電体の構造において、骨部１の途中に伸び吸収部４１を設けている。既に説明したように、シール鉛蓄電池の正極板は、使用中に酸化を受け、集電体の骨部１や縦桟部２、横桟部３に伸びが生じる。本第３実施形態では、集電体の骨部１が、この酸化による伸びに大きなウェイトを占めている点に着目し、集電体の強度や導電性等に影響を及ぼさない条件で、骨部１を集電体の周辺部から内側に移動させている。
【００２６】
本第３実施形態では、骨部１の伸びを吸収するための伸び吸収部４１を設けることで、伸び対策の効果をより確実なものとしている。なお、本第３実施形態では、集電体の全体寸法に変化をもたらすことがないので、活物質を塗布して極板を作製した際の塗布量にほとんど変化は無い。この結果、シール鉛蓄電池を構成した際の電気量への影響は無い。むしろ、集電体の伸びが抑制された分だけ、電槽と極板側部との離隔距離を小さくすることが可能となる。ゆえに、同一サイズの電槽に収納できる極板の大きさを大きくすることもできる。すなわち、同一の外形寸法のシール鉛蓄電池において、電池容量が向上するという効果もある。
【００２７】
次に、図３（ａ）、（ｂ）に示す構造の集電体によって極板作製と電池の組み立てを行なった場合の電池特性に対する効果について説明する。合金には、第１実施形態と同様に、鉛−カルシウム（０．０５％）−スズ（１．０％）−アルミニウム（０．０２％）合金を用い、ブックモールド鋳造法によって集電体を製造した。作製した集電体は、タブ４を含まない有効部の寸法が１３×１０ｃｍ（高さ×幅）で、厚みは骨部１で４ｍｍである。これらは、鋳型の溝加工部の形状を変えただけなので、骨部１の一部に吸収部４１が設けられる点を除き、ほとんど第１実施形態と同一の集電体になる。
【００２８】
このような集電体に活物質を塗布して正極板を作製し、正極板４枚／負極板５枚からなるシール鉛蓄電池を組み立てた。組み立てたシール鉛蓄電池は、定格電圧２Ｖ、１０時間率定格容量は３０Ａｈである。吸収部４１が設けられているものの、集電体全体サイズと活物質塗布面積とには違いが無いので、作製したシール鉛蓄電池の容量も替わらない。このシール鉛蓄電池について、高温下で連続充電を行ない、容量変化や試験終了後の極板の伸び状況の確認を行った。
【００２９】

【００３０】
この結果、図６に示すように、本第３実施形態によるシール鉛蓄電池では、１４ヶ月後にも７０％の容量が保たれた。すなわち、吸収部４１の配置によって伸びの抑制効果が向上していることが分かる。従来技術による集電体を使用したシール鉛蓄電池に比べると、寿命が４０％改善されていることになる。なお、１４ヶ月試験した後のシール鉛蓄電池を解体し、正極板の寸法変化を測定した結果、本第３実施形態によるシール鉛蓄電池における伸びが抑制されていた。
【００３１】
従来品：９％（６０℃、１０ヶ月後）
第３実施形態：４％（６０℃、１４ヶ月後）
【００３２】
上述したように、本第３実施形態によれば、第１実施形態と同様に、長期にわたってシール鉛蓄電池を使用した際に生じる集電体の伸びの吸収が図られ、電槽破壊やこれによる電解液の漏れといった二次的な問題の発生も抑えることができるという利点が得られる。この結果、電池寿命の延伸と正極板の伸び抑制が可能となり、より大きな効果を得ることができる。すなわち、本第３実施形態においては、シール鉛蓄電池のコンパクト化に対して一層の効果を得ることができる。ゆえに、同一サイズの極板を使用しても電池全体の寸法を小さくすることができ、単位体積あたりのエネルギー（放電電気量）密度の高い電池の実現することができる。
【００３３】
Ｄ．第３実施形態の変形例
なお、上述した第３実施形態による集電体における伸び吸収部４１に関しては、図３（ａ）、（ｂ）に示したような連続した骨部１の途中に曲線状の吸収部４１を設ける方法以外でも対応することができる。この例を図４、図５に示した。これらの図においては、骨部１を連続した一体型で作製するのではなく、骨部１を分割し、敢えて位置をずらして配置し、食い違い部４２を形成している。鉛合金に生じる応力は、物体の断面積に応じた値になるので、断面積が大きい骨部１では、縦桟部２、横桟部３に比べて応力が大きくなる。そこで、図４、図５に示すの集電体では、縦方向か横方向のいずれかに食い違い部４２を設けている。該食い違い部４２によって、骨部１に生じた大きな応力を途中で分断し、集電体全体に生じる伸びの力の低減化を図っている。
【００３４】
したがって、第３実施形態の変形例によれば、長期にわたってシール鉛蓄電池を使用した際に生じる集電体の伸びの吸収が図られ、電槽破壊やこれによる電解液の漏れといった二次的な問題の発生も抑えることができる。また、同一サイズの極板を使用しても電池全体の寸法を小さくすることができ、単位体積あたりのエネルギー（放電電気量）密度の高い電池の実現することができる。
【００３５】
以上の述べたように、本発明は、シール鉛蓄電池のこれまでの問題であった正極板の伸び抑制と電池サイズの小型に寄与するものであり、各種用途用の小型シール鉛蓄電池や産業用大型シール鉛蓄電池に適用可能であり、産業上、極めて大きな効果を有している。
【００３６】
【発明の効果】
以上説明したように、本発明によれば、骨部と桟部とによって正極板と負極板を交互に組み合わせ、全面に電極活物質が塗布されて極板が形成された集電体の前記骨部を前記集電体の内側に配置するようにしたので、使用した際に生じる集電体の伸びが吸収され、長期間にわたって使用しても電槽破壊等を発生することなく、高い信頼性を確保することができるという利点が得られる。
【図面の簡単な説明】
【図１】本発明の第１実施形態によるシール鉛蓄電池の集電体の構成を示す平面図および断面図である。
【図２】本発明の第２実施形態によるシール鉛蓄電池の集電体の構成を示す平面図である。
【図３】本発明の第３実施形態によるシール鉛蓄電池の集電体の構成を示す平面図および断面図である。
【図４】本発明の変形例によるシール鉛蓄電池の集電体の構成を示す平面図である。
【図５】本発明の変形例によるシール鉛蓄電池の集電体の構成を示す平面図である。
【図６】従来技術による集電体と本発明による集電体を適用したシール鉛蓄電池の容量推移の比較例を示す概念図である。
【図７】従来技術によるシール鉛蓄電池の集電体の構造例を示す平面図および断面図である。
【符号の説明】
１骨部
２縦桟部（桟部）
３横桟部（桟部）
４タブ
４１伸び吸収部
４２食い違い部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a lead-acid battery in which an electrode group in which a plurality of positive and negative electrode plates are assembled via a separator is housed in a battery case together with sulfuric acid.
[0002]
[Prior art]
A sealed lead-acid battery is configured by storing a group of electrode plates in which a plurality of positive and negative electrode plates are assembled via a separator together with sulfuric acid in a battery case. The positive / negative electrode plate is formed by applying an active material involved in a battery reaction to a current collector having a lattice-shaped opening such as a bar of a shoji. The role of the current collector is to retain the active material involved in the reaction and to secure a path for the current accompanying charge and discharge.
[0003]
FIG. 7A is a plan view showing a structural example of a current collector of a lead storage battery according to the related art, and FIG. 7B is a cross-sectional view thereof. In FIG. 7 (a), a bone portion 1 constitutes an outer peripheral portion of the current collector, also serving as reinforcement of the entire current collector, and has a vertical beam portion 2 extending vertically therein and a horizontal beam portion extending horizontally. 3 are arranged. As shown in FIG. 7B, the thickness of the bone 1, the vertical bar 2, and the horizontal bar 3 is larger in the former. The electrode is formed by applying an active material to such a current collector.
[0004]
On the other hand, in the positive electrode, when used as a standby power source, the current collector is always subjected to a charging reaction, so that the current collector is subjected to electrochemical oxidation. For this reason, the surface of the current collector is oxidized, and when the current collector is used for a long period of time, it becomes difficult to hold the active material, and the function as a battery becomes impossible. For this reason, an alloy used for the current collector has been studied. In a sealed lead-acid battery, a lead alloy of lead, calcium, and tin is used for the current collector (for example, see Non-Patent Document 1).
[0005]
[Patent Document 1]
GS News technical Report, June 1998, Vol. 57, No. 1, p. 16
[0006]
[Problems to be solved by the invention]
However, in the above-described conventional lead-acid battery, since the current collector is manufactured by a casting method using a lead alloy containing calcium and tin, “grain” is formed in the alloy, and the “grain” is formed between each “grain”. Forms an interface. Since the current collector is in a charged state during use of the battery, the current collector is oxidized. Oxidation (corrosion) easily proceeds at the interface between the “grain” due to the oxidation. For this reason, lead sulfate, which is a product of oxidation at the grain boundaries, is generated, and the entire current collector alloy is elongated, making it difficult to retain the active material. Fall into. The elongation of the current collector in the outer peripheral direction may reach as much as 10%. Therefore, the battery case accommodating the electrode group is damaged by being squeezed by the elongated positive electrode plate, leaking the electrolyte, Furthermore, there was a risk of secondary disaster such as surrounding corrosion and fire due to the leaked electrolyte.
[0007]
The present invention has been made in view of the above-described circumstances, and has as its object to provide a lead storage battery that can ensure high reliability without causing battery case breakdown or the like even when used for a long period of time. .
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, in the invention according to claim 1, the electrode active material is applied to the entire surface of a current collector in which a positive electrode plate and a negative electrode plate are alternately combined by a skeleton and a crosspiece. A lead-acid battery having a plate formed therein, wherein the skeleton is arranged inside the current collector.
[0009]
According to a second aspect of the present invention, in the lead storage battery according to the first aspect, the skeleton is formed in a rectangular shape inside the current collector.
[0010]
According to a third aspect of the present invention, in the lead storage battery according to the first aspect, the bone is radially formed inside the current collector.
[0011]
According to a fourth aspect of the present invention, in the lead-acid battery according to the second aspect, the bone portion has a stretch-absorbing portion formed in a curved shape at least in a part of either the longitudinal direction or the lateral direction. It is characterized by the following.
[0012]
According to a fifth aspect of the present invention, in the lead-acid battery according to the second aspect, the skeleton is formed by being divided inside the current collector, and is arranged so as to be shifted from each other. And
[0013]
Further, in the invention according to claim 6, in the lead-acid battery according to any one of claims 1 to 5, the current collector includes calcium (0.04 to 0.1% by weight) and tin (0.1 to 0.1% by weight). 2.5% by weight) and a lead alloy containing aluminum or silver (0.005 to 0.05% by weight) as a main component.
[0014]
According to a seventh aspect of the present invention, in the lead storage battery according to any one of the first to fifth aspects, when the current collector is housed in a battery case, the side and bottom portions of the positive electrode plate are connected to the battery. The distance from the inner wall of the tank is 5% or less of the width and height of the positive electrode plate.
[0015]
In the present invention, the positive electrode plate and the negative electrode plate are alternately combined by the skeleton and the crosspiece, and the skeleton of the current collector in which the electrode active material is applied over the entire surface to form the electrode plate is placed inside the current collector. To place. Therefore, the elongation of the current collector that occurs during use is absorbed, and high reliability can be ensured without causing battery case destruction or the like even when used for a long period of time.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0017]
A. First Embodiment FIG. 1A is a plan view showing a configuration of a current collector of a sealed lead-acid battery according to a first embodiment of the present invention, and FIG. 1B is a cross-sectional view thereof. In FIG. 1, based on the conventional current collector structure shown in FIG. 7, the position of the bone 1 having a larger cross-sectional area than the vertical bar 2 and the horizontal bar 3 is shifted from the outermost side of the current collector to the inside. It has a moved structure.
[0018]
Next, the effect on the battery characteristics when the electrode plate is manufactured and the battery is assembled using the current collector having the structure shown in FIGS. 1A and 1B will be described. Specifically, a current collector was manufactured by a book mold casting method using a lead-calcium (0.05%)-tin (1.0%)-aluminum (0.02%) alloy. The produced current collector has an effective portion that does not include the tab 4, has a size of 13 × 10 cm (height × width), and has a thickness of 4 mm at the bone portion 1. In the case of using the casting method, since the overall size of the cast body and the size of the bone of the current collector are determined by engraving the entire mold, it is easy to manufacture the current collector having the structure according to the first embodiment by adjusting the mold. I was able to Further, for comparison, a current collector according to the prior art shown in FIGS. 7A and 7B was prepared in the same manner.
[0019]
An active material was applied to such a current collector to produce a positive electrode plate, and a sealed lead-acid battery including four positive electrode plates / five negative electrode plates was assembled. The assembled sealed lead-acid battery has a rated voltage of 2 V and a rated capacity of 10 hours at 30 Ah. These sealed lead-acid batteries were continuously charged at a high temperature, and the change in capacity and the elongation of the electrode plate after the test were confirmed.
[0020]

[0021]
As a result, as shown in FIG. 6, in the sealed lead-acid battery using the current collector according to the conventional technique, the capacity after being left for about 10 months in a 60 ° C. environment was reduced to 70% or less of the initial value. In the sealed lead storage battery according to the first embodiment, it was confirmed that 70% of the capacity was maintained even after 12 months. That is, in the first embodiment, it can be seen that the life is improved by 20% as compared with the sealed lead-acid battery using the conventional current collector. In addition, as a result of disassembling the sealed lead-acid battery after the end of the above-mentioned period and measuring the dimensional change of the positive electrode plate, elongation in the sealed lead-acid battery according to the first embodiment was suppressed as described below.
[0022]
Conventional product: 9% (after 60 months at 60 ° C)
1st Embodiment: 5% (after 60 months, 12 months)
[0023]
As described above, according to the first embodiment, absorption of the elongation of the current collector that occurs when the sealed lead storage battery is used for a long period of time is achieved, and secondary damage such as battery case destruction and leakage of the electrolyte due to this is achieved. Problems can be suppressed. As a result, it is understood that the battery life is extended and the elongation of the positive electrode plate is suppressed, and that the separation distance from the inner wall of the battery case is about 5% is sufficient. That is, when current collectors of the same size are used, the size of the battery case can be reduced, and the size of the battery can be reduced.
[0024]
B. Second Embodiment Next, FIG. 2 is a plan view showing a configuration of a current collector of a sealed lead-acid battery according to a second embodiment of the present invention. In the figure, the bone portion 1 in the current collector has a so-called radial structure extending from the portion of the tab 4 toward the peripheral portion. In the current collector according to the prior art, a portion located at the upper end and the left end of the bone portion 1 is located on the outermost side, and the other portions extend to the end of the current collector. On the other hand, in the second embodiment, all the bones 1 are arranged in a portion inside the current collector.
[0025]
C. Third Embodiment Next, FIG. 3A is a plan view showing a configuration of a current collector of a sealed lead storage battery according to a third embodiment of the present invention, and FIG. 3B is a sectional view thereof. . In the third embodiment, as shown in the drawing, in the structure of the current collector according to the above-described first embodiment, a stretch absorbing part 41 is provided in the middle of the bone 1. As described above, the positive electrode plate of the sealed lead-acid battery is oxidized during use, and the skeleton 1, the vertical bar 2, and the horizontal bar 3 of the current collector expand. In the third embodiment, attention is paid to the fact that the bone portion 1 of the current collector occupies a large weight in the elongation due to the oxidation, and is performed under the condition that the strength and the conductivity of the current collector are not affected. The part 1 is moved inward from the peripheral part of the current collector.
[0026]
In the third embodiment, the effect of the measure against elongation is made more reliable by providing the elongation absorbing part 41 for absorbing the elongation of the bone part 1. In the third embodiment, since there is no change in the overall dimensions of the current collector, there is almost no change in the amount of application when the active material is applied to produce the electrode plate. As a result, there is no effect on the quantity of electricity when the sealed lead storage battery is configured. Rather, the distance between the battery case and the side of the electrode plate can be reduced by the amount by which the elongation of the current collector is suppressed. Therefore, the size of the electrode plates that can be stored in the same size battery case can be increased. That is, there is also an effect that the battery capacity is improved in the sealed lead storage batteries having the same external dimensions.
[0027]
Next, the effect on battery characteristics when the electrode plate is manufactured and the battery is assembled using the current collector having the structure shown in FIGS. 3A and 3B will be described. Similar to the first embodiment, a lead-calcium (0.05%)-tin (1.0%)-aluminum (0.02%) alloy is used for the alloy, and the current collector is formed by book mold casting. Manufactured. The produced current collector has an effective portion that does not include the tab 4, has a size of 13 × 10 cm (height × width), and has a thickness of 4 mm at the bone portion 1. These are merely the same current collectors as those of the first embodiment except that the shape of the grooved portion of the mold is changed, so that the absorbing portion 41 is provided in a part of the bone portion 1.
[0028]
An active material was applied to such a current collector to produce a positive electrode plate, and a sealed lead-acid battery including four positive electrode plates / five negative electrode plates was assembled. The assembled sealed lead-acid battery has a rated voltage of 2 V and a rated capacity of 10 hours at 30 Ah. Although the absorber 41 is provided, there is no difference between the current collector overall size and the active material application area, so the capacity of the manufactured sealed lead storage battery does not change. The sealed lead-acid battery was continuously charged at a high temperature, and the change in capacity and the elongation of the electrode plate after the test were confirmed.
[0029]

[0030]
As a result, as shown in FIG. 6, in the sealed lead storage battery according to the third embodiment, the capacity of 70% was maintained even after 14 months. That is, it can be seen that the effect of suppressing the elongation is improved by the arrangement of the absorbing portions 41. The service life is improved by 40% as compared with the sealed lead storage battery using the current collector according to the prior art. The sealed lead-acid battery after the 14-month test was disassembled and the dimensional change of the positive electrode plate was measured. As a result, the elongation of the sealed lead-acid battery according to the third embodiment was suppressed.
[0031]
Conventional product: 9% (after 60 months at 60 ° C)
Third Embodiment: 4% (after 60 months at 60 ° C.)
[0032]
As described above, according to the third embodiment, as in the first embodiment, absorption of the elongation of the current collector that occurs when the sealed lead-acid battery is used for a long period of time is achieved, and the battery case is broken and This has the advantage that secondary problems such as electrolyte leakage can be suppressed. As a result, it is possible to extend the battery life and suppress the elongation of the positive electrode plate, and a greater effect can be obtained. That is, in the third embodiment, a further effect can be obtained with respect to downsizing of the sealed lead storage battery. Therefore, even if the same size electrode plates are used, the overall size of the battery can be reduced, and a battery having a high energy (discharge electricity) density per unit volume can be realized.
[0033]
D. Modification of Third Embodiment The stretch absorbing portion 41 of the current collector according to the third embodiment described above has a curved portion in the middle of the continuous bone portion 1 as shown in FIGS. 3 (a) and 3 (b). It is possible to cope with any method other than the method of providing the absorption portion 41 having the shape of a circle. This example is shown in FIGS. In these figures, the bone part 1 is not manufactured as a continuous and integral type, but the bone part 1 is divided and deliberately shifted in position to form the staggered part 42. Since the stress generated in the lead alloy is a value corresponding to the cross-sectional area of the object, the stress is larger in the bone 1 having a large cross-sectional area than in the vertical bar 2 and the horizontal bar 3. Therefore, in the current collector shown in FIGS. 4 and 5, the staggered portion 42 is provided in either the vertical direction or the horizontal direction. The staggered portion 42 divides a large stress generated in the bone portion 1 on the way to reduce the elongation force generated in the entire current collector.
[0034]
Therefore, according to the modification of the third embodiment, absorption of the elongation of the current collector caused when the sealed lead-acid battery is used for a long period of time is achieved, and secondary damage such as battery case destruction and leakage of the electrolyte due to this is achieved. Problems can be suppressed. In addition, even if the same size electrode plates are used, the overall dimensions of the battery can be reduced, and a battery having a high energy (discharge electricity) density per unit volume can be realized.
[0035]
As described above, the present invention contributes to suppressing the elongation of the positive electrode plate and reducing the size of the battery, which have been problems of the sealed lead-acid battery so far. It is applicable to large sealed lead-acid batteries, and has an extremely large industrial effect.
[0036]
【The invention's effect】
As described above, according to the present invention, a positive electrode plate and a negative electrode plate are alternately combined by a bone portion and a bar portion, and an electrode active material is applied on the entire surface to form an electrode plate. The portion is arranged inside the current collector, so that the elongation of the current collector generated when used is absorbed, and even if the device is used for a long period of time, the battery case is not broken, and high reliability is obtained. Is obtained.
[Brief description of the drawings]
FIGS. 1A and 1B are a plan view and a cross-sectional view illustrating a configuration of a current collector of a sealed lead storage battery according to a first embodiment of the present invention.
FIG. 2 is a plan view showing a configuration of a current collector of a sealed lead storage battery according to a second embodiment of the present invention.
FIGS. 3A and 3B are a plan view and a cross-sectional view illustrating a configuration of a current collector of a sealed lead storage battery according to a third embodiment of the present invention.
FIG. 4 is a plan view showing a configuration of a current collector of a sealed lead storage battery according to a modification of the present invention.
FIG. 5 is a plan view showing a configuration of a current collector of a sealed lead storage battery according to a modification of the present invention.
FIG. 6 is a conceptual diagram showing a comparative example of a change in capacity of a sealed lead storage battery to which a current collector according to the prior art and a current collector according to the present invention are applied.
FIG. 7 is a plan view and a cross-sectional view showing a structural example of a current collector of a sealed lead storage battery according to the related art.
[Explanation of symbols]
1 Bone 2 Vertical cross section (cross section)
3 horizontal cross section (cross section)
4 Tab 41 Elongation absorption part 42 Staggered part

Claims

A positive electrode plate and a negative electrode plate, a lead-acid battery in which an electrode active material is applied to the entire surface of a current collector obtained by alternately combining a bone portion and a bar portion to form an electrode plate,
The lead storage battery, wherein the bone part is arranged inside the current collector.

The lead-acid battery according to claim 1, wherein the skeleton is formed in a rectangular shape inside the current collector.

The lead storage battery according to claim 1, wherein the skeleton is formed radially inside the current collector.

3. The lead-acid battery according to claim 2, wherein the skeleton has a stretch-absorbing portion formed in a curved shape at least in a part of one of a vertical direction and a horizontal direction.

3. The lead-acid battery according to claim 2, wherein the skeleton is formed by being divided inside the current collector, and is arranged so as to be shifted from each other.

The current collector contains calcium (0.04 to 0.1% by weight), tin (0.1 to 2.5% by weight), and aluminum or silver (0.005 to 0.05% by weight). The lead-acid battery according to any one of claims 1 to 5, wherein the lead-acid battery contains a lead alloy as a main component.

In a state where the current collector is accommodated in the battery case, a separation distance between a side portion and a bottom portion of the positive electrode plate and an inner wall of the battery case is 5% or less of a width and a height of the positive electrode plate. The lead-acid battery according to any one of claims 1 to 5, wherein: