JP4146000B2

JP4146000B2 - Connection structure between batteries

Info

Publication number: JP4146000B2
Application number: JP24452698A
Authority: JP
Inventors: 三郎中塚; 瑞夫岩崎
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 1998-08-31
Filing date: 1998-08-31
Publication date: 2008-09-03
Anticipated expiration: 2018-08-31
Also published as: JP2000077052A

Description

【０００１】
【発明の属する技術分野】
本発明は、主として複数の単電池を直列接続して所要の出力電圧を得る蓄電池モジュールを形成する電池間接続構造に関するものである。
【０００２】
【従来の技術】
従来から、複数個の単電池を直列接続して所要の出力電圧を得る蓄電池モジュールを形成するに際しては、単電池間を接続するための接続体が用いられている。すなわち、一般的な電池は、一端面を除く全体を外装する金属製の電池ケースがマイナス電極を兼ね、電池ケースの一端側の開口部が、プラス電極となる金属製の電極板を含む封口体により閉塞された構造になっており、隣接して接続すべき各２個の単電池のうちの一方の単電池の電極板（プラス電極）と他方の単電池の電池ケース（マイナス電極）とを単一の接続体の各所要箇所に電気的に接続することにより、２個の電池間の直列接続がなされる。ここで、接続体と２個の電池の各々の所要箇所とは、スポット溶接することによって電気的に直列接続するとともに、機械的に連結されている。
【０００３】
ところで、通常のスポット溶接は、溶接する部分を２つの溶接電極間で挟圧して溶接電流を流すことにより、挟圧間が溶融して溶接されるのであるが、上述のスポット溶接に際しては、挟圧ができないので、多くの電流が接続体および電極板の表面電流として溶接電極間に流れるため、接続体として厚い材厚のものや、比抵抗の小さいものを使用したとき、溶接が困難になる問題がある。すなわち、従来の電池間接続構造では、接続体として、材厚の大きい材料や比抵抗の小さい材料を使用できないため、単電池間の電気的接続の電気抵抗が大きく、比較的大きな電流が流れる電池間接続での損失が大きくなり、さらに、接続体の機械的強度も低いことから、電池間の機械的連結の強度も低くなる。
【０００４】
そこで、本件出願人は、接続体構成の改良と溶接方法の改良とにより、接続抵抗の低下と接続強度の向上を図って従来構成の問題点を解消した電池間接続構造を既に提案している（特開平10-106533 号公報参照）。この電池間接続構造は図７の縦断面図に示すような構成になっている。接続体１は、一方の電池Ｂ１のプラス電極である電極板２に当接する平坦な底板部３と、他方の電池Ｂ２のマイナス電極を兼ねる電池ケース４に嵌合する筒状部７とを有し、キャップ状正極端子６を挿通させる孔を底板部３の中央部に有する容器形状になっている。筒状部７と底板部３とには、それぞれ同一円上に複数のプロジェクション溶接用突起８，９が形成されている。同図は溶接前の状態を示したものであり、接続体１の底板部３と一方の電池Ｂ１の電極板２とは、突起９を介してプロジェクション溶接することにより、突起９が溶融して互いに密着状態に溶着し、接続体１の筒状部７と他方の電池Ｂ２の電池ケース４とは突起８を介してプロジェクション溶接することにより、突起８が溶融して互いに密着状態に溶着する。なおキャップ状正極端子６は前記電極板２にプロジェクション溶接や通常のスポット溶接を用いて溶接されている。
【０００５】
【発明が解決しようとする課題】
上記プロジェクション溶接は、接続すべき２つの部材を突起８，９による小さな接触面積で接触させて、その接触面積が小さいことによって最も抵抗値が大きくなる突起８，９の接触箇所に電流を局部的に集中させて発熱させ、発熱による溶融によって溶接を行うものであり、通常のスポット溶接のような１対の溶接電極による挟圧を必要としない。上記の電池間接続構造は、接続体１を上述のようなプロジェクション溶接により隣接する２個の電池Ｂ１，Ｂ２の所要箇所に溶着するので、接続体１として構成する材料の材厚や比抵抗に左右されることが少ない上に、溶接強度も向上させることができる。さらに、電極板２と電池ケース４との溶接位置は同一円上の複数箇所であるため、接続による電流経路は最短距離となることから、接続抵抗の小さい電気的接続と機械的強度の高い連結とを得ることができる。
【０００６】
しかしながら、上記の電池間接続構造は、上述のような効果を得られるものであるが、実用化に際して、さらなる改良を必要とする問題が残存している。すなわち、隣接する２個の電池Ｂ１，Ｂ２を接続するに際して、接続体１の底板部３を一方の電池Ｂ１の電極板２にプロジェクション溶接したのちに、接続体１の筒状部７を他方の電池Ｂ２の電池ケース４にプロジェクション溶接するので、溶接が２工程となる。このように、上記の電池間接続構造は、溶接工程が多いことと、接続体１を有して部品点数が多くなることとにより、コスト高になっている。
【０００７】
また、上述の電池間接続構造は、所要個数の電池Ｂ１，Ｂ２をその長手方向に配列して直列接続するものであるが、これとは別に、図８に示すように、所要個数の円筒型電池Ｂ１〜Ｂ３をその径方向に沿って一列に並べて、その隣接する各２個の電池相互間を接続体１０で電気的に直列接続する構成の電池間接続構造も存在する（特開平10-27599号公報参照）。このような電池間接続構造により所要個数の電池Ｂ１〜Ｂ３を直列接続してなる蓄電池モジュールは、特に電車の給電停止時の照明点灯用バックアップ電源などに多く用いられている。
上記の電池間接続構造に用いられる接続体１０は、板状体を略直角に折曲した略逆Ｌ字型形状を有し、一端面１０ａが電池ケース４の外周面に沿った湾曲形状を有し、その一端面１０ａに複数のスリット１０ｂと小突起１０ｃとが設けられている。そして、接続体１０の一端面１０ａは、スリット１０ｂにより若干変形されて電池ケース４の曲面形状に沿わせられた状態で、小突起１０ｃを介してスポット溶接して電池ケース４に溶着される。そののちに、接続体１０の他端面１０ｄが隣接する電池の電極板２にスポット溶接により溶着される。
【０００８】
この接続体１０による電池間接続構造においても、接続体１０の一端面１０ａを隣接する２個のうちの一方の電池の電池ケース４にスポット溶接したのちに、接続体１０の他端面１０ｄを他方の電池の電極板２にスポット溶接するので、溶接が２工程となり、やはり、溶接工程が多いことと、接続体１０を有して部品点数が多くなることとにより、コスト高になっている。しかも、スポット溶接に際して、接続体１０の一端面１０ａはスリット１０ｂを介して変形させながら電池ケース４の曲面となった外周面に沿わせる必要があるため、溶接の作業性が悪い。
【０００９】
そこで本発明は、上記従来の課題に鑑みてなされたもので、その目的とするところは、プロジェクション溶接による接続の利点を活かしながら、溶接回数を１回減らし、コストを低減して所要個数の単電池を電気的に直列接続することのできる電池間接続構造を提供することにある。
【００１０】
【課題を解決するための手段】
上記目的を達成するために、本発明は、一方の電極を兼ねる有底筒状の電池ケースと、他方の電極を兼ねる電極板および弁体などにより構成されて前記電池ケースの一端側の開口部を閉塞する封口体とを有する電池を複数個備え、これら電池を長手方向に沿って直列または径方向に沿って並列に配置して、隣接する各２個の電池間を溶接により互いに電気的に直列接続して連結する電池間接続構造において、電池の一構成部材としての正極端子部材が、前記電極板との間に前記弁体の収納空間を形成すると共にガス放出孔が設けられたキャップ部と、このキャップ部から一体に延びる接続基板部と、この接続基板部から前記電池ケースの外側方に延びる導出板部と、この導出板部の先端に設けられた接続電極部とを一体に備えてなり、前記接続基板部を前記電極板に溶接により電気接続状態に連結することにより前記電極板と前記キャップ部との間に弁体を収納し、隣接する各２個のうちの一方の電池の前記正極端子部材における前記接続電極部を、これに設けたプロジェクション溶接用突起を介して他方の電池の前記電池ケースにプロジェクション溶接することにより直接連結して、複数の電池間を直列接続した構造になっている。
【００１１】
この電池間接続構造では、接続電極部が一体形成された正極端子部材を有して蓄電池モジュール専用の構成となった電池を用いることにより、隣接する各２個の電池の正極端子部材と電池ケースとを、１回の溶接工程で接続体を介さずに直接的に接続できるとともに、従来の接続体が不要となって部品点数が低減するので、この溶接工程の削減と接続体などの部品点数の低減とにより、相当のコストダウンを達成できる。
【００１２】
上記発明において、正極端子部材は、電池ケースの中央部に位置するキャップ部から前記電池ケースの径方向の両側に向けてそれぞれ接続基板部、導出板部および接続電極部が帯状に一体に延出しているとともに、両端部に位置する一対の前記接続電極部が、前記電池ケースの径に相当する間隔で相対向するよう屈曲形成された形状に形成され、長手方向に沿って隣接する各２個のうちの一方の電池の一対の前記接続電極部間に他方の電池の前記電池ケースが嵌め込まれて溶接されている構成とすることができる。
【００１３】
これにより、所要個数の電池を長手方向に沿って直列に配置する構成の蓄電池モジュールに適用でき、隣接する２個のうちの一方の電池の正極端子部材が他方の電池の電池ケースに対しその径方向の両端部に溶着されるので、電池間の曲げ強度が向上して安定性の良い連結状態となり、連結の機械的強度を十分に確保できる。
【００１４】
また、上記発明において、正極端子部材は、電池ケースの中央部に位置するキャップ部から電池ケースの径方向の一方側に向けて接続基板部、導出板部および接続電極部が帯状に一体に延出しているとともに、前記接続電極部が電池ケースの外周面に対し外側方で、且つ平行に配置された形状に形成され、長手方向に沿って隣接する各２個のうちの一方の電池の前記接続電極部が他方の電池の前記電池ケースの外面に接触して溶接されている構成とすることができる。
【００１５】
これにより、所要個数の電池を長手方向に沿って直列に配置する構成の蓄電池モジュールに適用でき、正極端子部材の形状が簡素化されているから、その分だけ材料コストを低減できる点がある。また、隣接する２個の電池は、その径方向の一端側でのみ溶着されるだけであるが、この溶着部分を配列する電池一つ毎に径方向の両端側に交互に配置するようにすれば、所要個数の電池を直列接続した蓄電池モジュール全体として見た場合に、曲げ強度が向上して安定性の良い連結状態となり、連結の機械的強度を十分に確保できる。
【００１６】
さらに、上記発明において、正極端子部材は、電池ケースの中央部に位置するキャップ部から電池ケースの径方向の一方側に向けて接続基板部、導出板部および接続電極部がほぼ直線的に一体に延出した形状に形成され、径方向に沿って隣接する各２個のうちの一方の電池の前記接続電極部を他方の電池の前記電池ケースの底面に接触させて溶接した構成とすることもできる。
【００１７】
これにより、所要個数の電池をその径方向に沿って一列に並べて、その隣接する各２個の電池相互間を電気的に直列接続する構成の蓄電池モジャールに適用することができ、並列状態に隣接する各２個のうちの一方の電池の正極端子部材の先端の接続電極部を、他方の電池の電池ケースの平坦な底面に溶着できるので、湾曲形状に変形させて電池ケースの外周面に接触させる従来構造に比較して溶接作業が容易となり、強固な溶着状態を確実に得ることができ、連結の機械的強度が向上する。
【００１８】
【発明の実施の形態】
以下、本発明の好ましい実施の形態について図面を参照しながら説明する。図１は本発明の第１の実施の形態に係る電池間接続構造を示した縦断面図であり、同図には、電池要素などの本発明に直接的に係わりのない部材の図示を省略して、要部のみを図示してあり、また、図７と同一若しくは同等のものには同一の符号を付してある。隣接して接続される２個の電池Ｂａ１，Ｂａ２は、共に同一種類で同一規格のものであり、その一方の電池Ｂａ１の斜視図を図２に示す。なお、図１には２個のみの電池Ｂａ１，Ｂａ２を示しているが、接続すべき所要個数の電池は全て同一種類で同一規格ものである。これら電池Ｂａ１，Ｂａ２のマイナス電極を兼ねる電池ケース４は、円柱状の電池Ｂａ１，Ｂａ２の一端面を除く全体を覆う有底円筒状になっている。この電池ケース４の一端開口部は、ガスケット１１、プラス電極を兼ねる電極板２、ゴム弁体１２および正極端子部材１３により構成された封口体１４により閉塞されている。
【００１９】
正極端子部材１３は、図２に明示するように、図７に示した従来の電池Ｂ１，Ｂ２におけるキャップ状正極端子６とほぼ同じ断面逆Ｕ字型形状となったキャップ部１７と、このキャップ部１７の下端部周囲から一体に両側に延びる帯板状の接続基板部１８と、接続基板部１８の両端部から立ち上がり部１９を介して接続基板部１８に対し上方位置で平行に延びる一対の導出板部２０と、各導出板部２０の先端部からほぼ直角に屈曲して上方に延びる一対の接続電極部２１とが一体形成されている。キャップ部１７には、図１に示すように、複数個のガス放出孔２２が穿設されている。
【００２０】
図１に示すように、平面視円形の金属製電極板２は、その中央部にガス排出孔２３が設けられ、周縁部をガスケット１１を介して電池ケース４に対し電気的に絶縁されて、かしめ加工された電池ケース４の開口部に固着されている。ゴム弁体１２は、電極板２とこの電極板２に溶着された正極端子部材１３における中央のキャップ部１７とにより構成された弁体収納空間２４内に封入されて、ガス排出孔２３を閉塞している。このゴム弁体１２は、電池内部のガス圧力が異常に上昇して弁開放圧に達したときに、ガス排出孔２３を通じて作用するガス圧力を受けて弾性変形し、ガス排出孔２３を開放する。それにより、電池内部のガスは、ガス排出孔２３およびキャップ部１７のガス放出孔２２を通じて電池外部に排出される。
【００２１】
図１は、電池Ｂａ１における正極端子部材１３を電極板２に溶接する前の状態を示したものであり、正極端子部材１３には、その接続基板部１８に複数個のプロジェクション溶接用突起２７が形成されているとともに、接続電極部２１の内側面にプロジェクション溶接用突起２８が形成されている。まず、本発明の電池間接続構造に用いる電池Ｂａ１，Ｂａ２について説明する。正極端子部材１３を電極板２に溶着する工程では、正極端子部材１３を、そのキャップ部１７を電極板２に対し位置決めして配置すると、接続基板部１８のプロジェクション溶接用突起２７が電極板２に当接する。この状態で、電極板２と正極端子部材１３とにそれぞれ上方から溶接電極を当接させてプロジェクション溶接を行う。
【００２２】
それにより、溶接電流は、接触面積が小さいことから接触抵抗が極めて小さい突起２７と電極板２との接触部分に局部的に集中して流れ、それによる発熱によって突起２７が溶融して、接続基板部１８全体が電極板２に密着状態で互いに溶着され、図２に示すような電池Ｂａ１が出来上がる。この溶接工程は、図７に示した従来の電池間接続構造に用いる電池Ｂ１，Ｂ２における製造工程においてキャップ状正極端子６を電極板２に溶接する工程と同等である。したがって、この実施の形態の電池間接続構造に用いる電池Ｂａ１，Ｂａ２は、図７に示した一般的な電池Ｂ１，Ｂ２と同数の工程で製造でき、蓄電池モジュール専用の構成を有したものとなる。
【００２３】
つぎに、上記構成を備えた電池Ｂａ１，Ｂａ２をそれらの長手方向に沿って所要個数だけ直列配置に重ねたときに、隣接する２個のうちの一方の電池Ｂａ１における正極端子部材１３の一対の接続電極部２１間に他方の電池Ｂａ２の電池ケース４が入り込み、接続電極部２１のプロジェクション溶接用突起２８が他方の電池Ｂａ２の電池ケース４に当接する。この状態で、一方の電池Ｂａ１の正極端子部材１３と他方の電池Ｂａ２の電池ケース４とにそれぞれ溶接電極（図示せず）を当接させてプロジェクション溶接を行う。このとき、一方の電池Ｂａ１に対する溶接電極は、正極端子部材１３における電池ケース４の外側に位置する接続電極部２１に極めて容易に当接させることができる。
【００２４】
それにより、溶接電流は、接触面積が小さいことから接触抵抗が極めて小さい突起２８と電池ケース４との接触部分に局部的に集中して流れ、それによる発熱によって突起２８が溶融して、一方の電池Ｂａ１における正極端子部材１３の接続電極部２１が他方の電池Ｂａ２の電池ケース４の側面に密着した状態で互いに溶着され、２個の電池Ｂａ１，Ｂａ２が直列接続されたことになる。このような電池間接続を所望の出力電圧が得られる数に連結して、蓄電池モジュールを構成することができる。ここで、上端に位置する電池としては、図７に示した通常の電池を用いることができる。
【００２５】
したがって、従来の電池間接続構造では、隣接する各２個の電池Ｂ１，Ｂ２を接続するに際して、接続体１の底板部３と筒状部７との２回の溶接工程を必要とするのに対して、上記実施の形態の電池間接続構造では、蓄電池モジュール専用の構成を有する電池Ｂａ１，Ｂａ２を用いることにより、隣接する各２個の電池Ｂａ１，Ｂａ２の各々の正極端子部材１３と電池ケースとを、１回の溶接工程で接続体を介さずに直接的に接続できるとともに、従来の接続体１が不要となって部品点数が低減する。この溶接工程の削減と接続体１などの部品点数の低減とにより、相当のコストダウンを達成できる。さらに、従来の接続体１が容器形状であるのに対し、この接続体１に相当する正極端子部材１３におけるキャップ部１７を除く部分は単なる帯状の板部材を屈曲加工したものであるから、材料コストも低減できる。また、正極端子部材１３は、電池ケース４に対しその径方向の両端部に溶着されるので、電池Ｂａ１，Ｂａ２間の曲げ強度が向上して安定性の良い連結状態となり、連結の機械的強度を十分に確保できる。
【００２６】
図３は本発明の第２の実施の形態に係る電池間接続構造を示す縦断面図で、図４はこの電池間接続構造に用いる電池Ｂａ１１を示す斜視図である。これらの図において、図１および図２と同一若しくは同等のものには同一の符号を付して、その説明を省略する。この実施の形態に用いる電池Ｂａ１１は、第１の実施の形態に用いた電池Ｂａ１，Ｂａ２と比較して、正極端子部材３０の形状が相違するだけである。すなわち、この実施の形態の電池Ｂａ１１における正極端子部材３０は、第１の実施の形態の正極端子部材１３と比較して、キャップ部１７の形状のみが同一であって、その他の接続基板部３１、立ち上がり部３２、導出板部３３および接続電極部３４がキャップ部１７から一方側にのみ延出した形状になっている。
【００２７】
図３は電池Ｂａ１１における接続基板部３１を電極板２に溶接前の状態を示したものであり、この電池Ｂａ１１は、接続基板部３１に設けた複数のプロジエクション溶接用突起２７を介してプロジェクション溶接することにより、正極端子部材３０を電極板２に溶着して構成される。したがって、この実施の形態の電池間接続構造に用いる電池Ｂａ１１は、図７に示した一般的な電池Ｂ１，Ｂ２と比較して製造工程が同数であるが、蓄電池モジュール専用の構成を有したものとなる。
【００２８】
また、図３は隣接する２個の電池Ｂａ１１，Ｂａ１２を溶接による接続および連結前の状態を示したもので、接続電極部３４の内側面にプロジェクション溶接用突起２８が形成されている。上記構成を備えた同一種類で同一規格の電池Ｂａ１１，Ｂａ１２をそれらの長手方向に所要個数だけ直列配置して接続するに際して、隣接する２個のうちの一方の電池Ｂａ１１における正極端子部材３０の接続電極部３４のプロジェクション溶接用突起２８を他方の電池Ｂａ１２の電池ケース４の外面に接触させた状態で、一方の電池Ｂａ１１の正極端子部材３０と他方の電池Ｂａ１２の電池ケース４とにそれぞれ溶接電極を当接させてプロジェクション溶接を行う。このとき、一方の電池Ｂａ１１に対する溶接電極は、正極端子部材３０における電池ケース４の外側に位置する接続電極部３４に極めて容易に当接させることができる。
【００２９】
それにより、一方の電池Ｂａ１１における正極端子部材３０の接続電極部３４は、突起２８の溶融によって他方の電池Ｂａ１２の電池ケース４の側面に密着した状態で互いに溶着され、２個の電池Ｂａ１１，Ｂａ１２が直列接続されたことになる。このような電池間接続を所望の出力電圧が得られる数に連結して、蓄電池モジュールを構成することができる。ここで、所要数のうちの上端に位置する電池としては、図７に示した通常の電池を用いることができる。
【００３０】
したがって、この実施の形態の電池間接続構造では、第１の実施の形態と同様に、蓄電池モジュール専用の構成を有する電池Ｂａ１１，Ｂａ１２を用いることにより、隣接する各２個の電池Ｂａ１１，Ｂａ１２の各々の正極端子部材３０と電池ケース４とを、１回の溶接工程で接続体を介さずに直接的に接続できるとともに、従来の接続体１が不要となって部品点数が低減し、この溶接工程の削減と接続体１などの部品点数の低減とにより、相当のコストダウンを達成できる。さらに、正極端子部材３０は、第１の実施の形態の正極端子部材１３に比較して形状が簡素化されているから、その分だけ材料コストが低減する利点がある。また、隣接する２個の電池Ｂａ１１，Ｂａ１２は、その径方向の一端側でのみ溶着されるだけであるが、この溶着部分を配列する電池一つ毎に径方向の両端側に交互に配置するようにすれば、所要個数の電池を直列接続した蓄電池モジュール全体として見た場合に、曲げ強度が向上して安定性の良い連結状態となり、連結の機械的強度を十分に確保できる。
【００３１】
図５は本発明の第３の実施の形態に係る電池間接続構造を示す縦断面図で、図６はその斜視図である。これらの図において、図１ないし図４と同一若しくは同等のものには同一の符号を付して、その説明を省略する。この実施の形態では、同一種類で同一規格の所要個数の電池Ｂａ２１，Ｂａ２２をその径方向に沿って一列に並べて、その隣接する各２個の電池Ｂａ２１，Ｂａ２２相互間を電気的に直列接続する構成の電池間接続構造の場合である。この実施の形態の電池間接続構造に用いる電池Ｂａ２１，Ｂａ２２は、第１および第２の実施の形態のものに比較して、正極端子部材３７の形状が相違するだけである。すなわち、この実施の形態の電池Ｂａ２１，Ｂａ２２における正極端子部材３７は、第１および第２の各実施の形態の正極端子部材１３，３０と比較して、キャップ部１７の形状のみが同一であって、このキャップ部１７の下端部周囲から一方向に延びる接続基板部３８、上方へ膨出して電池ケース４のかしめ部を回避しながら電池ケース４の外側方へ延びる導出板部３９および先端の接続電極部４０が帯状の板材を一部屈曲加工して形成されている。なお、９９は絶縁外装チューブである。
【００３２】
図５は電池Ｂａ２１における接続基板部３８を電極板２に溶接前の状態を示したものであり、この電池Ｂａ２１は、接続基板部３８に設けた複数のインジェクション溶接用突起２７を介してインジェクション溶接することにより、正極端子部材３７を電極板２に溶着して構成される。したがって、この実施の形態の電池間接続構造に用いる電池Ｂａ２１，Ｂａ２１は、図７に示した一般的な電池Ｂ１，Ｂ２と比較して製造工程が同数であるが、並列配置型の蓄電池モジュール専用の構成を有したものとなる。
【００３３】
また、図５は隣接する２個の電池Ｂａ２１，Ｂａ２２を溶接による接続および連結前の状態を示したもので、接続電極部４０の一面にプロジェクション溶接用突起４１が形成されている。上記構成を備えた同一種類で同一規格の電池Ｂａ２１，Ｂａ２２を、それらの径方向に沿って長手方向の向きを交互に逆にした配置で所要個数だけ配列して直列接続するに際して、隣接する２個のうちの一方の電池Ｂａ２１における正極端子部材３７の電池ケース４の外側方へ延びた接続電極部４０のインジェクション溶接用突起４１に、他方の電池Ｂａ２２の電池ケース４の底面を接触させた状態で、一方の電池Ｂａ２１の正極端子部材３７と他方の電池Ｂａ２２の電池ケース４とにそれぞれ溶接電極（図示せず）を当接させてプロジェクション溶接を行う。
【００３４】
それにより、一方の電池Ｂａ２１における正極端子部材３７の接続電極部４０は、突起４１の溶融によって他方の電池Ｂａ２２の電池ケース４の底面に密着した状態で互いに溶着され、２個の電池Ｂａ２１，Ｂａ２２が並列配置で電気的に直列接続されたことになる。このような電池間接続を所望の出力電圧が得られる数に連結して、蓄電池モジュールを構成することができる。
【００３５】
したがって、この実施の形態の電池間接続構造では、並列配置型蓄電池モジュール専用の構成を有する電池Ｂａ２１，Ｂａ２２を用いることにより、隣接する各２個の電池Ｂａ２１，Ｂａ２２の各々の正極端子部材３７と電池ケース４とを、１回の溶接工程で接続体を介さずに直接的に接続できるとともに、図８に示した従来の接続体１０が不要となって部品点数が低減し、この溶接工程の削減と接続体１０などの部品点数の低減とにより、相当のコストダウンを達成できる。さらに、正極端子部材３７は、隣接する電池Ｂａ２２の電池ケース４の平坦な底面に溶着するので、図８に示した従来構造における接続体１０のように、電池ケース４の外周面に対応した湾曲形状とし、且つスリット１０ｂを介して電池ケース４の外周面に沿うよう変形させる場合に比較して、溶接作業が容易となって強固な溶着状態を確実に得ることができ、連結の機械的強度が向上する。
【００３６】
【発明の効果】
以上のように、本発明の電池間接続構造によれば、電池を、接続電極部が一体形成された正極端子部材を用いて封口体を構成することによって、蓄電池モジュール専用の構成としたので、隣接する各２個の電池の正極端子部材と電池ケースとを、１回の溶接工程で直接的に接続できるとともに、従来の接続体が不要となって部品点数が低減するので、この溶接工程の削減と接続体などの部品点数の低減とにより、相当のコストダウンを達成できる。
【図面の簡単な説明】
【図１】本発明の第１の実施の形態に係る電池間接続構造の構成を示す縦断面図。
【図２】同上電池間接続構造に用いる電池の斜視図。
【図３】本発明の第２の実施の形態に係る電池間接続構造の構成を示す縦断面図。
【図４】同上電池間接続構造に用いる電池の斜視図。
【図５】本発明の第３の実施の形態に係る電池間接続構造の構成を示す縦断面図。
【図６】同上電池間接続構造の斜視図。
【図７】従来の電池間接続構造の構成を示す縦断面図。
【図８】従来の他の電池間接続構造の構成を示す縦断面図。
【符号の説明】
２電極板
４電池ケース
１２ゴム弁体（弁体）
１３，３０，３７正極端子部材
１４封口体
１７キャップ部
１８，３１，３８接続基板部
２０，３３，３９導出板部
２１，３４，４０接続電極部
２４弁体収納空間
２８，４１プロジェクション溶接用突起
Ｂａ１，Ｂａ２，Ｂａ１１，Ｂａ１２，Ｂａ２１，Ｂａ２２電池[0001]
BACKGROUND OF THE INVENTION
The present invention mainly relates to an inter-battery connection structure that forms a storage battery module that obtains a required output voltage by connecting a plurality of single cells in series.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, when forming a storage battery module that obtains a required output voltage by connecting a plurality of single cells in series, a connection body for connecting the single cells has been used. That is, in a general battery, a metal battery case that covers the entire surface excluding one end surface also serves as a negative electrode, and an opening on one end side of the battery case includes a metal electrode plate that serves as a positive electrode. The electrode plate (plus electrode) of one unit cell and the battery case (minus electrode) of the other unit cell among the two unit cells to be connected adjacent to each other are connected to each other. A series connection between two batteries is made by electrical connection to each required location of a single connection. Here, the connection body and each required portion of the two batteries are electrically connected in series by spot welding and mechanically coupled.
[0003]
By the way, in normal spot welding, a portion to be welded is sandwiched between two welding electrodes and a welding current is supplied to melt the sandwiched portion. Since pressure cannot be applied, a large amount of current flows between the welding electrodes as the surface current of the connection body and electrode plate, so that welding becomes difficult when a connection material with a large thickness or a small specific resistance is used. There's a problem. That is, in the conventional battery-to-battery connection structure, a material having a large thickness or a material having a small specific resistance cannot be used as a connection body. The loss in the inter-connection increases, and further, the mechanical strength of the connection body is low, so that the mechanical connection strength between the batteries is also low.
[0004]
Therefore, the present applicant has already proposed an inter-battery connection structure that solves the problems of the conventional configuration by reducing the connection resistance and improving the connection strength by improving the connection structure and the welding method. (See JP-A-10-106533). This inter-battery connection structure is configured as shown in the longitudinal sectional view of FIG. The connection body 1 has a flat bottom plate portion 3 that comes into contact with an electrode plate 2 that is a positive electrode of one battery B1, and a cylindrical portion 7 that fits into a battery case 4 that also serves as a negative electrode of the other battery B2. And it has a container shape having a hole through which the cap-like positive electrode terminal 6 is inserted in the center of the bottom plate portion 3. The cylindrical portion 7 and the bottom plate portion 3 are formed with a plurality of projection welding projections 8 and 9 on the same circle. This figure shows a state before welding, and the projection 9 is melted by projection welding the bottom plate portion 3 of the connection body 1 and the electrode plate 2 of one battery B1 through the projection 9. The cylindrical portion 7 of the connector 1 and the battery case 4 of the other battery B2 are welded to each other by projection welding via the protrusion 8, so that the protrusion 8 is melted and welded to each other. The cap-like positive terminal 6 is welded to the electrode plate 2 using projection welding or normal spot welding.
[0005]
[Problems to be solved by the invention]
In the projection welding, two members to be connected are brought into contact with each other with a small contact area by the projections 8 and 9, and current is locally applied to the contact portion of the projections 8 and 9 having the largest resistance value due to the small contact area. In this case, welding is performed by melting by heat generation, and no clamping pressure by a pair of welding electrodes as in normal spot welding is required. The inter-battery connection structure welds the connection body 1 to the required locations of the two adjacent batteries B1 and B2 by projection welding as described above, so that the material thickness and specific resistance of the material constituting the connection body 1 can be reduced. In addition to being less influenced, the welding strength can also be improved. Further, since the welding positions of the electrode plate 2 and the battery case 4 are a plurality of locations on the same circle, the current path by connection is the shortest distance, so that the electrical connection with a low connection resistance and the connection with a high mechanical strength are provided. And you can get
[0006]
However, although the above-described inter-battery connection structure can achieve the above-described effects, there still remains a problem that requires further improvement upon practical use. That is, when two adjacent batteries B1 and B2 are connected, after the bottom plate portion 3 of the connection body 1 is projection welded to the electrode plate 2 of one battery B1, the cylindrical portion 7 of the connection body 1 is connected to the other. Since projection welding is performed on the battery case 4 of the battery B2, welding is performed in two steps. As described above, the inter-battery connection structure has a high cost due to the large number of welding processes and the increased number of parts having the connection body 1.
[0007]
The above-described inter-battery connection structure is such that a required number of batteries B1 and B2 are arranged in series in the longitudinal direction and connected in series. However, as shown in FIG. There is also an inter-battery connection structure in which the batteries B1 to B3 are arranged in a line along the radial direction, and the two adjacent batteries are electrically connected in series by a connecting body 10 (Japanese Patent Laid-Open No. 10-101). 27599). A storage battery module in which a required number of batteries B1 to B3 are connected in series by such an inter-battery connection structure is often used particularly as a lighting power source for lighting when a train is stopped.
The connection body 10 used in the above-described inter-battery connection structure has a substantially inverted L-shaped shape obtained by bending a plate-like body at a substantially right angle, and one end surface 10a has a curved shape along the outer peripheral surface of the battery case 4. A plurality of slits 10b and small protrusions 10c are provided on one end face 10a. Then, one end face 10a of the connection body 10 is slightly deformed by the slit 10b and is welded to the battery case 4 by spot welding via the small protrusion 10c in a state of being along the curved shape of the battery case 4. After that, the other end surface 10d of the connection body 10 is welded to the adjacent electrode plate 2 of the battery by spot welding.
[0008]
Also in the inter-battery connection structure using this connection body 10, after spot welding the one end face 10a of the connection body 10 to the battery case 4 of one of the two adjacent batteries, the other end face 10d of the connection body 10 is connected to the other side. Spot welding is performed on the electrode plate 2 of the battery, so that the welding is performed in two steps, and the cost is increased due to the large number of welding steps and the increased number of parts including the connection body 10. Moreover, at the time of spot welding, one end surface 10a of the connection body 10 needs to be along the outer peripheral surface that is a curved surface of the battery case 4 while being deformed through the slit 10b, so that the workability of welding is poor.
[0009]
Accordingly, the present invention has been made in view of the above-described conventional problems, and the object of the present invention is to reduce the number of weldings by one, reduce the cost and reduce the number of required units while taking advantage of the connection by projection welding. An object of the present invention is to provide an inter-battery connection structure capable of electrically connecting batteries in series.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the present invention comprises a bottomed cylindrical battery case that also serves as one electrode, an electrode plate that also serves as the other electrode, a valve body, and the like, and an opening on one end side of the battery case. A plurality of batteries having a sealing body that closes the battery, and these batteries are arranged in series along the longitudinal direction or in parallel along the radial direction, and two adjacent batteries are electrically connected to each other by welding. In the inter-battery connection structure connected in series and connected, a positive terminal member as a constituent member of the battery forms a storage space for the valve body between the electrode plate and a cap part provided with a gas discharge hole And a connection board part integrally extending from the cap part, a lead-out plate part extending from the connection board part to the outside of the battery case, and a connection electrode part provided at the tip of the lead-out plate part. The connection By connecting the substrate part to the electrode plate in an electrically connected state by welding, the valve element is accommodated between the electrode plate and the cap part, and the positive terminal member of one of the two adjacent batteries. The connection electrode part in Through the projection welding projection provided on this In the battery case of the other battery Projection It is directly connected by welding and has a structure in which a plurality of batteries are connected in series.
[0011]
In this inter-battery connection structure, a positive terminal member and a battery case of two adjacent batteries are used by using a battery having a positive terminal member integrally formed with a connection electrode portion and having a configuration dedicated to a storage battery module. Can be directly connected without a connection body in a single welding process, and the conventional connection body is not required and the number of parts is reduced. A considerable cost reduction can be achieved by the reduction of the above.
[0012]
In the above invention, the positive terminal member includes a connecting substrate portion, a lead-out plate portion, and a connecting electrode portion that integrally extend in a band shape from a cap portion located at a central portion of the battery case toward both sides in the radial direction of the battery case. In addition, a pair of connection electrode portions located at both ends are formed in a shape that is bent so as to face each other at an interval corresponding to the diameter of the battery case, and each two adjacent electrode portions along the longitudinal direction. It can be set as the structure by which the said battery case of the other battery is inserted and welded between a pair of said connection electrode part of one battery of these.
[0013]
Thus, the battery can be applied to a storage battery module having a configuration in which a required number of batteries are arranged in series along the longitudinal direction, and the positive terminal member of one of the two adjacent batteries has a diameter relative to the battery case of the other battery. Since it is welded to both ends in the direction, the bending strength between the batteries is improved and a stable connection state is obtained, and the mechanical strength of the connection can be sufficiently secured.
[0014]
In the above invention, the positive terminal member includes a connecting substrate portion, a lead-out plate portion, and a connecting electrode portion that integrally extend in a strip shape from the cap portion located at the center of the battery case toward one side in the radial direction of the battery case. The connecting electrode portion is formed in a shape that is arranged outward and parallel to the outer peripheral surface of the battery case, and the battery of one of the two batteries adjacent to each other along the longitudinal direction is formed. It can be set as the structure by which the connection electrode part contacts the outer surface of the said battery case of the other battery, and is welded.
[0015]
Thereby, it can apply to the storage battery module of the structure which arranges a required number of batteries in series along a longitudinal direction, and since the shape of a positive electrode terminal member is simplified, there exists a point which can reduce material cost by that much. Further, two adjacent batteries are welded only at one end side in the radial direction, but the batteries are arranged alternately at both ends in the radial direction for each battery in which the welded portions are arranged. For example, when viewed as a whole storage battery module in which a required number of batteries are connected in series, the bending strength is improved and a stable connection state is obtained, and the mechanical strength of the connection can be sufficiently secured.
[0016]
Further, in the above invention, the positive terminal member includes the connection substrate portion, the lead-out plate portion, and the connection electrode portion that are integrated substantially linearly from the cap portion located at the center portion of the battery case toward one side in the radial direction of the battery case. The connection electrode part of one of the two batteries adjacent to each other in the radial direction is in contact with the bottom surface of the battery case of the other battery and welded. You can also.
[0017]
As a result, the required number of batteries can be arranged in a line along the radial direction, and can be applied to a storage battery modal that has a configuration in which two adjacent batteries are electrically connected in series. Since the connection electrode part at the tip of the positive electrode terminal member of one of the two batteries can be welded to the flat bottom surface of the battery case of the other battery, it is deformed into a curved shape and brought into contact with the outer peripheral surface of the battery case Compared to the conventional structure, the welding work is facilitated, and a strong welded state can be reliably obtained, and the mechanical strength of the connection is improved.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a connection structure between batteries according to a first embodiment of the present invention. In FIG. 1, illustration of members such as battery elements which are not directly related to the present invention is omitted. Only the main parts are illustrated, and the same or equivalent parts as those in FIG. 7 are denoted by the same reference numerals. Two batteries Ba1 and Ba2 connected adjacently are of the same type and of the same standard, and a perspective view of one battery Ba1 is shown in FIG. Although only two batteries Ba1 and Ba2 are shown in FIG. 1, the required number of batteries to be connected are all of the same type and of the same standard. The battery case 4 that also serves as the negative electrodes of the batteries Ba1 and Ba2 has a bottomed cylindrical shape that covers the whole of the cylindrical batteries Ba1 and Ba2 excluding one end face. One end opening of the battery case 4 is closed by a sealing body 14 including a gasket 11, an electrode plate 2 that also serves as a positive electrode, a rubber valve body 12, and a positive terminal member 13.
[0019]
As clearly shown in FIG. 2, the positive terminal member 13 includes a cap portion 17 having an inverted U-shaped cross section substantially the same as the cap-shaped positive terminal 6 in the conventional batteries B1 and B2 shown in FIG. A pair of strip-like connection board portions 18 that integrally extend from the periphery of the lower end portion of the portion 17 to both sides, and a pair of parallel extensions at an upper position with respect to the connection board portion 18 from both ends of the connection board portion 18 via the rising portions 19. The lead-out plate portion 20 and a pair of connection electrode portions 21 that are bent substantially at right angles from the tip end portion of each lead-out plate portion 20 and extend upward are integrally formed. As shown in FIG. 1, the cap portion 17 has a plurality of gas discharge holes 22.
[0020]
As shown in FIG. 1, the metal electrode plate 2 having a circular shape in plan view is provided with a gas discharge hole 23 in the center thereof, and the peripheral portion thereof is electrically insulated from the battery case 4 via the gasket 11, It is fixed to the opening of the caulked battery case 4. The rubber valve body 12 is enclosed in a valve body housing space 24 constituted by the electrode plate 2 and the central cap portion 17 of the positive electrode terminal member 13 welded to the electrode plate 2 to close the gas discharge hole 23. is doing. When the gas pressure inside the battery rises abnormally and reaches the valve opening pressure, the rubber valve body 12 is elastically deformed by the gas pressure acting through the gas discharge hole 23 and opens the gas discharge hole 23. . Thereby, the gas inside the battery is discharged out of the battery through the gas discharge hole 23 and the gas discharge hole 22 of the cap portion 17.
[0021]
FIG. 1 shows a state before the positive electrode terminal member 13 in the battery Ba1 is welded to the electrode plate 2. The positive electrode terminal member 13 has a plurality of projection welding projections 27 on the connection substrate portion 18. As shown in FIG. The projection welding projections 28 are formed on the inner surface of the connection electrode portion 21. First, the batteries Ba1 and Ba2 used in the inter-battery connection structure of the present invention will be described. In the step of welding the positive electrode terminal member 13 to the electrode plate 2, when the positive electrode terminal member 13 is disposed with its cap portion 17 positioned with respect to the electrode plate 2, the projection welding projection 27 of the connection substrate portion 18 is formed on the electrode plate 2. Abut. In this state, projection welding is performed by bringing the welding electrode into contact with the electrode plate 2 and the positive electrode terminal member 13 from above.
[0022]
As a result, the welding current flows locally in a concentrated manner at the contact portion between the projection 27 having a very small contact resistance and the electrode plate 2 because the contact area is small, and the projection 27 melts due to the heat generated thereby. The whole part 18 is welded to the electrode plate 2 in close contact with each other, and a battery Ba1 as shown in FIG. 2 is completed. This welding process is equivalent to the process of welding the cap-shaped positive terminal 6 to the electrode plate 2 in the manufacturing process of the batteries B1 and B2 used in the conventional inter-battery connection structure shown in FIG. Therefore, the batteries Ba1 and Ba2 used in the inter-battery connection structure of this embodiment can be manufactured in the same number of steps as the general batteries B1 and B2 shown in FIG. 7, and have a configuration dedicated to the storage battery module. .
[0023]
Next, when the required number of batteries Ba1 and Ba2 having the above configuration are stacked in series along the longitudinal direction, a pair of positive electrode terminal members 13 in one of the two adjacent batteries Ba1 The battery case 4 of the other battery Ba2 enters between the connection electrode portions 21, and the projection welding projection 28 of the connection electrode portion 21 contacts the battery case 4 of the other battery Ba2. In this state, a welding electrode (not shown) is brought into contact with the positive electrode terminal member 13 of one battery Ba1 and the battery case 4 of the other battery Ba2 to perform projection welding. At this time, the welding electrode for one battery Ba1 can be brought into contact with the connecting electrode portion 21 located outside the battery case 4 in the positive electrode terminal member 13 very easily.
[0024]
As a result, the welding current flows locally in a concentrated manner at the contact portion between the projection 28 having a very small contact resistance and the battery case 4 because the contact area is small, and the projection 28 melts due to heat generated thereby. The connection electrode portion 21 of the positive electrode terminal member 13 in the battery Ba1 is welded to each other in a state of being in close contact with the side surface of the battery case 4 of the other battery Ba2, and the two batteries Ba1 and Ba2 are connected in series. A storage battery module can be configured by connecting such inter-battery connections to a number that provides a desired output voltage. Here, as the battery positioned at the upper end, the normal battery shown in FIG. 7 can be used.
[0025]
Therefore, the conventional inter-battery connection structure requires two welding steps of the bottom plate portion 3 and the cylindrical portion 7 of the connection body 1 when connecting each two adjacent batteries B1, B2. On the other hand, in the inter-battery connection structure of the above embodiment, the positive electrode terminal member 13 and the battery case of each of the two adjacent batteries Ba1 and Ba2 are used by using the batteries Ba1 and Ba2 having a configuration dedicated to the storage battery module. Can be directly connected without a connection body in one welding process, and the conventional connection body 1 is not necessary, and the number of parts is reduced. A considerable cost reduction can be achieved by reducing the number of parts such as the connecting body 1 and the welding process. Furthermore, while the conventional connection body 1 has a container shape, the portion other than the cap portion 17 in the positive electrode terminal member 13 corresponding to the connection body 1 is formed by bending a simple band-shaped plate member. Cost can also be reduced. Further, since the positive electrode terminal member 13 is welded to both ends of the battery case 4 in the radial direction, the bending strength between the batteries Ba1 and Ba2 is improved and a stable connection state is obtained, and the mechanical strength of the connection is increased. Can be secured sufficiently.
[0026]
FIG. 3 is a longitudinal sectional view showing a battery connection structure according to the second embodiment of the present invention, and FIG. 4 is a perspective view showing a battery Ba11 used in the battery connection structure. In these drawings, the same or equivalent components as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof is omitted. The battery Ba11 used in this embodiment is different from the batteries Ba1 and Ba2 used in the first embodiment only in the shape of the positive electrode terminal member 30. In other words, the positive electrode terminal member 30 in the battery Ba11 of this embodiment is the same as the positive electrode terminal member 13 of the first embodiment only in the shape of the cap portion 17, and the other connection substrate portion 31. The rising portion 32, the lead-out plate portion 33, and the connection electrode portion 34 have a shape extending only from the cap portion 17 to one side.
[0027]
FIG. 3 shows a state before the connection substrate portion 31 of the battery Ba11 is welded to the electrode plate 2. The battery Ba11 is connected to the connection substrate portion 31 via a plurality of projection welding projections 27. The positive terminal member 30 is welded to the electrode plate 2 by projection welding. Therefore, the battery Ba11 used in the inter-battery connection structure of this embodiment has the same number of manufacturing steps as the general batteries B1 and B2 shown in FIG. 7, but has a configuration dedicated to the storage battery module. It becomes.
[0028]
FIG. 3 shows a state before two adjacent batteries Ba11 and Ba12 are connected and joined by welding, and a projection welding projection 28 is formed on the inner surface of the connection electrode portion 34. FIG. When the required number of batteries Ba11 and Ba12 of the same type and the same standard having the above configuration are connected in series in the longitudinal direction, the positive terminal member 30 is connected in one of the two adjacent batteries Ba11. In a state where the projection welding projection 28 of the electrode part 34 is in contact with the outer surface of the battery case 4 of the other battery Ba12, the welding electrode is respectively applied to the positive terminal member 30 of one battery Ba11 and the battery case 4 of the other battery Ba12. Projection welding is performed with the contact. At this time, the welding electrode for one battery Ba11 can be brought into contact with the connection electrode portion 34 located outside the battery case 4 in the positive electrode terminal member 30 very easily.
[0029]
Thereby, the connection electrode part 34 of the positive electrode terminal member 30 in one battery Ba11 is welded to each other in a state of being in close contact with the side surface of the battery case 4 of the other battery Ba12 by melting of the protrusion 28, and the two batteries Ba11, Ba12. Are connected in series. A storage battery module can be configured by connecting such inter-battery connections to a number that provides a desired output voltage. Here, as the battery located at the upper end of the required number, the normal battery shown in FIG. 7 can be used.
[0030]
Therefore, in the inter-battery connection structure of this embodiment, similarly to the first embodiment, by using the batteries Ba11 and Ba12 having a configuration dedicated to the storage battery module, each of the two adjacent batteries Ba11 and Ba12 is used. Each positive terminal member 30 and the battery case 4 can be directly connected without a connection body in a single welding process, and the conventional connection body 1 is not required and the number of parts is reduced. A considerable cost reduction can be achieved by reducing the number of processes and the number of components such as the connection body 1. Furthermore, since the positive electrode terminal member 30 has a simplified shape as compared with the positive electrode terminal member 13 of the first embodiment, there is an advantage that the material cost is reduced accordingly. The adjacent two batteries Ba11 and Ba12 are welded only at one end in the radial direction, but are alternately arranged at both ends in the radial direction for each battery in which the welded portions are arranged. If it does in this way, when it sees as the whole storage battery module which connected the required number of batteries in series, bending strength will improve and it will be in a stable connection state, and can ensure sufficient mechanical strength of connection.
[0031]
FIG. 5 is a longitudinal sectional view showing the inter-battery connection structure according to the third embodiment of the present invention, and FIG. 6 is a perspective view thereof. In these drawings, the same or equivalent components as those in FIGS. 1 to 4 are denoted by the same reference numerals, and the description thereof is omitted. In this embodiment, the required number of batteries Ba21 and Ba22 of the same type and the same standard are arranged in a line along the radial direction, and the two adjacent batteries Ba21 and Ba22 are electrically connected in series. This is the case of the inter-battery connection structure. The batteries Ba21 and Ba22 used in the inter-battery connection structure of this embodiment are different from the first and second embodiments only in the shape of the positive electrode terminal member 37. That is, the positive electrode terminal member 37 in the batteries Ba21 and Ba22 of this embodiment is the same as the positive electrode terminal members 13 and 30 of the first and second embodiments only in the shape of the cap portion 17. The connection board 38 extending in one direction from the periphery of the lower end of the cap 17, the lead-out plate 39 extending upward and avoiding the caulking portion of the battery case 4, and the tip of the leading end 39 The connection electrode portion 40 is formed by bending a strip-shaped plate material partially. Reference numeral 99 denotes an insulating outer tube.
[0032]
FIG. 5 shows a state before the connection substrate portion 38 of the battery Ba21 is welded to the electrode plate 2. This battery Ba21 is injection welded via a plurality of injection welding projections 27 provided on the connection substrate portion 38. By doing so, the positive electrode terminal member 37 is welded to the electrode plate 2. Accordingly, the batteries Ba21 and Ba21 used in the inter-battery connection structure of this embodiment have the same number of manufacturing steps as compared with the general batteries B1 and B2 shown in FIG. It has the following structure.
[0033]
FIG. 5 shows a state before connection and connection of two adjacent batteries Ba21 and Ba22 by welding, and a projection welding projection 41 is formed on one surface of the connection electrode portion 40. FIG. When two or more batteries Ba21 and Ba22 of the same type and the same standard having the above-described configuration are arranged in series and connected in series in the arrangement in which the direction of the longitudinal direction is alternately reversed along the radial direction, two adjacent batteries are connected. A state in which the bottom surface of the battery case 4 of the other battery Ba22 is in contact with the injection welding projection 41 of the connection electrode portion 40 of the positive electrode terminal member 37 extending outward of the battery case 4 of one of the batteries Ba21. Thus, projection welding is performed by bringing a welding electrode (not shown) into contact with the positive electrode terminal member 37 of one battery Ba21 and the battery case 4 of the other battery Ba22.
[0034]
Thereby, the connection electrode portion 40 of the positive electrode terminal member 37 in one battery Ba21 is welded to each other in a state of being in close contact with the bottom surface of the battery case 4 of the other battery Ba22 by melting of the protrusion 41, and the two batteries Ba21, Ba22. Are electrically connected in series in a parallel arrangement. A storage battery module can be configured by connecting such inter-battery connections to a number that provides a desired output voltage.
[0035]
Therefore, in the inter-battery connection structure of this embodiment, by using the batteries Ba21 and Ba22 having a configuration dedicated to the parallel-arranged storage battery module, the positive electrode terminal member 37 of each of the two adjacent batteries Ba21 and Ba22 and The battery case 4 can be directly connected to the battery case 4 without a connection body in one welding process, and the conventional connection body 10 shown in FIG. A considerable cost reduction can be achieved by the reduction and the reduction of the number of parts such as the connection body 10. Further, since the positive electrode terminal member 37 is welded to the flat bottom surface of the battery case 4 of the adjacent battery Ba22, the curve corresponding to the outer peripheral surface of the battery case 4 is provided like the connection body 10 in the conventional structure shown in FIG. Compared with the case of deforming the battery case 4 along the outer peripheral surface of the battery case 4 through the slit 10b, the welding operation is facilitated and a strong welded state can be reliably obtained, and the mechanical strength of the connection Will improve.
[0036]
【The invention's effect】
As described above, according to the inter-battery connection structure of the present invention, the battery is configured exclusively for the storage battery module by configuring the sealing body using the positive electrode terminal member integrally formed with the connection electrode portion. The positive electrode terminal member and the battery case of each two adjacent batteries can be directly connected in a single welding process, and the number of parts is reduced because the conventional connection body is not required. A considerable cost reduction can be achieved by reducing the number of parts such as connecting bodies.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a configuration of an inter-battery connection structure according to a first embodiment of the present invention.
FIG. 2 is a perspective view of a battery used in the inter-battery connection structure.
FIG. 3 is a longitudinal sectional view showing a configuration of an inter-battery connection structure according to a second embodiment of the present invention.
FIG. 4 is a perspective view of a battery used in the inter-battery connection structure.
FIG. 5 is a longitudinal sectional view showing a configuration of an inter-battery connection structure according to a third embodiment of the present invention.
FIG. 6 is a perspective view of the inter-battery connection structure.
FIG. 7 is a longitudinal sectional view showing a configuration of a conventional inter-battery connection structure.
FIG. 8 is a longitudinal sectional view showing a configuration of another conventional connection structure between batteries.
[Explanation of symbols]
2 Electrode plate
4 Battery case
12 Rubber disc (valve)
13, 30, 37 Positive terminal member
14 Sealing body
17 Cap part
18, 31, 38 Connection board
20, 33, 39 Deriving plate part
21, 34, 40 Connection electrode
24 Valve body storage space
28, 41 Projection welding projection
Ba1, Ba2, Ba11, Ba12, Ba21, Ba22 batteries

Claims

A plurality of batteries each having a bottomed cylindrical battery case that also serves as one electrode, and a sealing body that is configured by an electrode plate and a valve body that also serves as the other electrode and closes the opening on one end side of the battery case In the inter-battery connection structure in which these batteries are arranged in series along the longitudinal direction or in parallel along the radial direction, and two adjacent batteries are electrically connected in series with each other by welding,
A positive electrode terminal member as one constituent member of the battery forms a storage space for the valve body between the electrode plate and a cap portion provided with a gas discharge hole, and a connection substrate portion extending integrally from the cap portion And a lead-out plate portion extending outward from the battery case from the connection substrate portion, and a connection electrode portion provided at the tip of the lead-out plate portion,
A valve body is housed between the electrode plate and the cap portion by connecting the connection substrate portion to the electrode plate in an electrically connected state by welding,
The connection electrode portion of the positive electrode terminal member of one of the two adjacent batteries is directly connected by projection welding to the battery case of the other battery via a projection welding projection provided on the connection electrode portion. A connection structure between batteries, wherein a plurality of batteries are connected in series.

The positive terminal member has a connection substrate part, a lead-out plate part and a connection electrode part integrally extending in a strip shape from the cap part located in the center part of the battery case toward both sides in the radial direction of the battery case, The pair of connection electrode portions located at both ends are formed in a shape that is bent so as to be opposed to each other at an interval corresponding to the diameter of the battery case, and each of two adjacent electrodes along the longitudinal direction. The inter-battery connection structure according to claim 1, wherein the battery case of the other battery is fitted and welded between the pair of connection electrode portions of the one battery.

A plurality of batteries each having a bottomed cylindrical battery case that also serves as one electrode, and a sealing body that is configured by an electrode plate and a valve body that also serves as the other electrode and closes the opening on one end side of the battery case In the inter-battery connection structure in which these batteries are arranged in series along the longitudinal direction or in parallel along the radial direction, and two adjacent batteries are electrically connected in series with each other by welding,
A positive electrode terminal member connected to the electrode plate in an electrically connected state forms a storage space for the valve body with the electrode plate, and extends integrally from the cap portion and welds to the electrode plate. A connection board part coupled in an electrically connected state by the above, a lead-out plate part extending from the connection board part to the outside of the battery case, a connection electrode part provided at a tip of the lead-out plate part, and the connection electrode And a projection welding projection provided on the portion, and the connection electrode portion of the positive terminal member of one of the two adjacent batteries is connected to the projection welding projection provided on the projection welding projection. Directly connected by projection welding to the battery case of the other battery, and a battery connection structure in which a plurality of batteries are connected in series,
The positive terminal member has a connection substrate portion, a lead-out plate portion, and a connection electrode portion integrally extending in a band shape from the cap portion located at the center portion of the battery case toward one side in the radial direction of the battery case, The connection electrode part is formed in a shape that is arranged outward and parallel to the outer peripheral surface of the battery case, and the connection electrode part of one of the two batteries adjacent in the longitudinal direction is An inter-battery connection structure, wherein the battery case is in contact with and welded to the outer surface of the battery case of the other battery.

The positive electrode terminal member has a shape in which the connection substrate portion, the lead-out plate portion, and the connection electrode portion extend substantially linearly and integrally from the cap portion located at the center portion of the battery case toward one side in the radial direction of the battery case. 2. The welded battery according to claim 1, wherein the connection electrode portion of one of two batteries adjacent to each other along the radial direction is in contact with the bottom surface of the battery case of the other battery and welded. Connection structure between batteries.