JP4754094B2

JP4754094B2 - Manufacturing method of battery electrode plate

Info

Publication number: JP4754094B2
Application number: JP2001148777A
Authority: JP
Inventors: 恒義村上; 克博岡本; 芳之多田
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2001-05-18
Filing date: 2001-05-18
Publication date: 2011-08-24
Anticipated expiration: 2021-05-18
Also published as: JP2002343345A

Description

【０００１】
【発明の属する技術分野】
本発明は、例えば、ニッケル水素蓄電池、ニッケルカドミウム蓄電池およびリチウムイオン蓄電池などの二次電池において電解液と共に発電要素を構成する電池用電極板であって、特に、三次元発泡メタルなどの多孔質を有する芯材に活物質が充填されてなる非焼結式の電池用電極板の製造方法に関するものである。
【０００２】
【従来の技術】
二次電池の電極板としては、高多孔度を有する連続した三次元的な網目構造を有する発泡メタルを芯材として、この芯材に活物質を充填したものが、充電容量の面で非常に優れていることから、広く採用されている。さらに、近年の電池には高率放電特性の向上が強く求められており、その対応策としては以下のような構成が採用されている。
【０００３】
すなわち、高率放電特性の向上を図った電池用電極板は、芯材に活物質を充填した活物質充填部の一辺に沿った箇所に充填済みの活物質を除去した芯材露出部を形成するとともに、その芯材露出部を、活物質の充填前または除去後に圧縮して空隙率を低下させることにより、集電部を形成し、この集電部に接続リード部を溶接により接合した構成とする。
【０００４】
角形電池用電極群は、上記集電部を有する正負の電極板をその間にセパレータを介在して交互に積み重ねて構成される。一方、円筒形電池用電極群は、上記集電部を有する正負の電極板をその間にセパレータを介在して重ね合わせた状態で渦巻き状に巻回して構成される。したがって、何れの電極群においても、両端部に接続リード部が接合された正負の集電部が複数または全周にわたって形成されるから、この両端の接続リード部に集電板を接合することにより、各電極板から個々にまたは渦巻き状の全周部分から集電することが可能となって全体の集電効率が向上する。しかも、上記集電部は金属の芯材が露出されて接続リード部を溶接するのに適した状態になっているから、その接続リード部に集電板などを溶接により接合するタブレス方式によって集電特性が格段に向上し、上述の高率放電特性を向上させるという要望に対応することができる。
【０００５】
上述のような高率放電特性の向上を図ることができる電池用電極板は、例えば、図９に示すような工程を経て製造されている（特開2000-315498 号公報参照）。先ず、同図（ａ１）に示す第１工程では、発泡メタルなどの三次元構造を有する芯材１に、両側辺に沿った凹み部と、この凹み部に平行であって凹み部の２倍の溝幅を有する複数本の溝部とを、プレス成型または圧縮工程を経て形成する。つぎに、凹み部および溝部を含む芯材１全体には、スラリー状またはペースト状の活物質を充填し、続いて、凹み部および溝部にそれぞれ付着している活物質をブラシとエアーブローを用いた手段で除去して芯材１を露出させたのちに、活物質を乾燥させることにより、活物質充填部２と、上記凹み部および溝部に対応する箇所における芯材露出部３とを形成する。つぎに、溝部に対応する芯材露出部３は、その溝幅の中央の破線で示す切断線に沿って切断することにより、帯状の活物質充填部２の長手方向に沿う両端部に芯材露出部３を有する極板フープ４を製作する。
【０００６】
同図（ｂ）に示す第２工程では、一対の圧縮ロール（図示せず）の間を通過して圧縮を施された上記極板フープ４の芯材露出部３に、上下の一対の円板電極７，８を用いたシーム溶接工法によって帯状金属板であるリードフープ９を接合する。
【０００７】
同図（ｃ）に示す第３工程では、トリミングパンチ１０とトリミングダイ１１とを用いてリードフープ９に対し打ち抜き加工を施すことにより、リードフープ９を接続リード部１２に成形する。この接続リード１２を成形した極板フープ４は、製作すべき電極板の極板幅に相当する距離ずつ間欠送りしながら、切断パンチ１３と切断ダイ１４とを用いて電池外装缶内に収納するときの規格寸法に切断する。これにより、図７（ｂ）に示すように、活物質充填部２の一端部に接続リード部１２を有する角形電池用の電極板１７が出来上がる。なお、円筒形電池用の電極板は、上述したとほぼ同様の工程を経て製作され、角形電池用と相違するのは、接続リード部の形状と角形電池用の極板幅よりも長い長さに切断することだけである。
【０００８】
また、従来では、図９（ａ１）の第１の工程に代えて、同図（ａ２）に示す工程が採用されることもある。この（ａ２）の工程では、芯材１の全体に活物質を充填したのちに圧延工程を経ることにより、全体に活物質充填部２を形成し、その活物質充填部２の辺縁部に沿った所定箇所に、活物質を完全に除去することを目的として振幅を大きく設定した超音波振動を超音波ホーンヘッド１８から付与することにより、活物質を剥離しながら除去して芯材露出部３を形成している。（特開2000-77054号公報参照）。
【０００９】
【発明が解決しようとする課題】
しかしながら、上述した従来の製造方法では、後述する理由により、芯材露出部３の幅Ｄを図７（ｂ）に示すように大きく設定する必要があり、その芯材露出部３の大きな幅Ｄ分だけ活物質充填部２の体積、つまり単位体積当たりの活物質量が減少して、電池を構成したときの高容量化を図ることができないという問題がある。
【００１０】
すなわち、芯材露出部３を、例えば図１０（ａ）に示すようにリードフープ９の接合に必要なだけの可及的に小さな幅ｄに設定した場合には、上下の円板電極７，８によるシーム溶接工法によってリードフープ９を芯材露出部３に接合するときに、活物質充填部２における芯材露出部３に近接箇所の活物質の一部が両円板電極７，８間に入り込むおそれがある。両円板電極７，８の間に活物質充填部２から入り込んだ活物質は大きな電気抵抗となるため、スパークを発生させて円板電極７，８、リードフープ９および芯材露出部３の何れか又はこれらの全てが溶ける不良が生じる。その結果、溶接部分には焼き付きや連続スパークなどが発生して、連続したシーム溶接を行えなくなる不具合が生じる。しかも、円板電極７，８は、発生するスパークによって消耗するので、所要の寿命を確保することができない。
【００１１】
そこで、従来では、同図（ｂ）に示すように、芯材露出部３を十分に大きな幅Ｄに設定して、上述した焼き付きや連続スパークなどの発生を確実に防止するようにしている。これに伴って、従来の電極板１７は、単位体積当たりの活物質量が減少し、電池を構成したときの高容量化を阻害する要因になっている。なお、芯材露出部３は、リードフープ９を接合すべき箇所をリードフープ９の接合に先立って予め圧縮される場合と、図１０（ａ），（ｂ）に２点鎖線で示すように、リードフープ９の接合時に一対の円板電極７，８によってリードフープ９を溶接するのと同時に圧縮される場合とがある。
【００１２】
一方、図９（ａ２）の工程は、活物質を完全に除去しながら幅の小さい芯材露出部３を形成することを目的としたものであるが、この場合にも芯材露出部３の幅を小さく設定すれば、超音波振動の付与が不安定となり、形成された芯材露出部３内に活物質が残存してしまう。そのため、どうしても活物質を多めに剥離する必要があるので、結局、形成された芯材露出部３は、（ａ１）の工程を用いた場合と同様に幅が大きくなってしまい、上述したと同様の問題が生じる。
【００１３】
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、単位体積当たりの活物質量の大きい電池用電極板を支障なく製造できる製造方法を提供することを目的とするものである。
【００１４】
【課題を解決するための手段】
上記目的を達成するために、第１の発明に係る電池用電極板の製造方法は、多孔質を有する薄板状の芯材の全体に活物質を充填する活物質充填工程と、前記活物質が充填済みの活物質充填部の辺縁部に沿って超音波振動を付与することにより、活物質を除去した帯状の芯材露出部を前記活物質充填部に沿って形成する活物質除去工程と、前記芯材露出部における辺縁部に沿った所定箇所にリードフープを溶接により接合するリードフープ接合工程と、前記芯材露出部における前記リードフープが接合されていない箇所を前記活物質充填部に向け加圧しながら圧縮して極小幅とする幅寄せ圧縮工程と、前記活物質充填部およびリードフープを規定寸法に裁断して個々の電池用電極板に分割する裁断工程とを有していることを特徴としている。
【００１５】
この電池用電極板の製造方法では、活物質充填部を、後工程で芯材露出部を圧縮して極めて小さい幅とできる分を見込んで予め大きな体積に設定することができから、活物質量が相当に増大する。また、十分に大きな幅とした芯材露出部のうちの所要幅の部分にリードフープを溶接により接合したのちに芯材露出部を小さな幅に圧縮するので、溶接時における焼き付きや連続スパークの発生を確実に防止して、溶接に用いる電極などの長寿命化を図ることができる。さらに、一連の連続した製造工程中に幅寄せ圧縮工程が介在するだけであるから、生産性の低下を招くことがない。また、リードフープを接合した状態でのリードフープの位置ずれなどに起因する寸法ばらつきを、幅寄せ圧縮工程において芯材露出部の幅を縮小するときに修正できるから、高い寸法精度を得ることができる。
【００１６】
第２の発明に係る電池用電極板の製造方法は、多孔質を有する薄板状の芯材の全体に活物質を充填する活物質充填工程と、前記活物質が充填済みの活物質充填部の辺縁部に沿って超音波振動を付与することにより、活物質を除去した帯状の芯材露出部を前記活物質充填部に沿って形成する活物質除去工程と、前記芯材露出部における辺縁部に沿った所定箇所にリードフープを溶接により接合するリードフープ接合工程と、前記活物質充填部、芯材露出部およびリードフープを規定寸法に切断して個々の電極板素体に分割する切断工程と、前記各電極板素体における前記芯材露出部の前記リードフープが接合されていない箇所を前記活物質充填部に向け加圧しながら極小幅に圧縮することにより、前記各電極板素体を電極板とする幅寄せ圧縮工程とを有していることを特徴としている。
【００１７】
この電池用電極板の製造方法では、第１の発明と同様に、活物質充填部を、後工程で芯材露出部を圧縮して極めて小さい幅とできる分を見込んで予め大きな体積に設定することができから、活物質量が相当に増大する。また、十分に大きな幅とした芯材露出部のうちの所要幅の部分を圧縮した集電部にリードフープを溶接により接合したのちに芯材露出部を圧縮するので、溶接時における焼き付きや連続スパークの発生を確実に防止して、溶接に用いる電極などの長寿命化を図ることができる。さらに、一連の連続した製造工程中に幅寄せ圧縮工程が介在するだけであるから、生産性の低下を招くことがない。また、リードフープを接合した状態でのリードフープの位置ずれなどに起因する寸法ばらつきを、幅寄せ圧縮工程において芯材露出部の幅を縮小するときに修正できるから、高い寸法精度を得ることができる。
【００１８】
上記第２の発明における幅寄せ圧縮工程において、正極側または負極側の電極板素体と負極側または正極側の電極板とをこれらの間にセパレータを介在して重ね合わせた状態で幅寄せ治具の内部または電池ケースの内部に固定したのち、前記電極板素体における芯材露出部のリードフープが接合されていない箇所を前記活物質充填部に向け加圧しながら極小幅に圧縮することもできる。
【００１９】
これにより、電極板素体を、これの芯材露出部の幅を圧縮して小さくすることによって所要形状の電極板とすると同時に、角形電池用または円筒形電池用の電極群を構成することができるから、電池の生産性の一層の向上を図ることが可能となる。
【００２０】
上記各発明において、活物質除去工程を経て形成された芯材露出部のうちの辺縁部に沿った所定箇所にリードフープを溶接により接合し、前記芯材露出部のうちの前記リードフープの接合箇所を、接合前または接合時に圧縮して集電部とし、幅寄せ圧縮工程において、残存する芯材露出部に、リードフープに加えた押圧力を前記集電部を介し付与することにより、前記芯材露出部を活物質充填部寄りに加圧して圧縮することが好ましい。
【００２１】
これにより、リードフープが接合されている集電部は、残存する芯材露出部に比較して、圧縮されたことによって機械的な強度や密度が高められているので、芯材露出部を圧縮しながらリードフープと一体的に移動して、残存する芯材露出部を容易、且つ確実に圧縮することができる。
【００２２】
同上の幅寄せ圧縮工程において、リードフープのうちの所定長さを外方に突出させた配置で活物質充填部を支持台上に載置し、極板押えにおける２段階に突出した２つの規制面を前記リードフープと前記活物質充填部および芯材露出部とに対し少許の間隙で対向させた状態で、前記リードフープにおける前記支持台からの突出部分を前記支持台寄りに押し込んだのち、前記極板押えを前記間隙分だけ前記支持台側に近接移動させることが好ましい。
【００２３】
これにより、リードフープは、極板押えの規制面に対し少許の間隙を有しているから、規制面に曲がり変形するのが防止されながら摺動して円滑に移動する。一方、芯材露出部は、極板押えの規制面に対し少許の間隙を有しているから、僅かに膨れ上がりながらスムーズに圧縮される。そののち、極板押えが間隙分だけ支持台側に近接移動したときに、芯材露出部における圧縮時の膨出部分を加圧して、芯材露出部を活物質充填部と面一となるよう修正できる。
【００２５】
【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つつ詳細に説明する。図１は本発明の第１の実施の形態に係る電池用電極板の製造方法を具現化した製造工程を順に示した斜視図である。この実施の形態では、積層型電極群を構成して角形電池に用いる電池用電極板を製造する場合を例示してある。
【００２６】
先ず、（ａ）に示す所定サイズの矩形状若しくは帯状の三次元発泡メタルからなる芯材２１の全体に、（ｂ）に示すように活物質を充填して活物質充填部２２とする。この活物質充填部２２の形成に際しては、プレス加工前であって全く凹凸のない芯材２１に対し活物質を充填するので、全体にわたり均一な充填密度に充填できるとともに、凹凸つまり高低差がないことから、充填した活物質が流動することなく内部に保持されて、均一な充填密度を保持したまま乾燥される。これに対し従来の製造方法による図９（ａ１）の工程では、プレス成型または圧延工程を経て凹み部および溝部を予め形成した芯材１に活物質を充填するので、凹凸面の存在に起因して活物質の充填密度にばらつきが生じる。
【００２７】
つぎに、上述のように均一な充填密度の活物質充填部２２が形成された芯材２１は、（ｃ）に示すように、後工程において芯材露出部となる部分を除く全ての部分にプレス加工が施されることにより、ほぼ１／２に圧縮され、後工程で芯材露出部となる部分が２本の平行なレール状の残存凸条部２３として残存する。このプレス加工には、図示していないが、本件出願人による出願に係る特願2000-261471 号における図２に示したストライプロールプレス機と基本構造が同じであって、加工プレスロールが所定の配置で設けられたストライプロールプレス機が用いられる。
【００２８】
続いて、２つの残存凸条部２３は、（ｄ）に示す活物質除去工程において、自体の内部に充填されている活物質充填部２２が除去されることにより、２つの芯材露出部２４とされる。この活物質除去工程では、上述した特願2000-261471 号における図４に示した超音波振動器を備えた活物質除去装置とほぼ同様の構成を有する活物質除去装置（図示せず）を用いて処理される。ここでの芯材露出部２４の幅Ｄは、後工程でリードフープを接合するのに必要な所定幅よりも大きく設定されている。それにより、超音波振動器からは、十分に大きな振幅に設定した超音波振動を付与することができ、活物質の結合度の如何に関わらず、活物質を残存することなく完全に除去した芯材露出部２４を形成することができる。
【００２９】
つぎに、（ｅ）に示すように、各芯材露出部２４のうちのリードフープを接合するのに必要な所定幅ｄの部分は、プレスロール（図示せず）で圧縮されて、残存する元の芯材露出部２４よりも一段低い集電部２７とされる。続いて、（ｆ）に示すように、集電部２７には、図１０に示したと同様の一対の円板電極７，８を用いたシーム溶接工法によってリードフープ９が接合される。このリードフープ９は、十分に大きな幅Ｄに設定して活物質を完全に除去した芯材露出部２４の一部を圧縮してなる集電部２７にシーム溶接するのとともに、一対の円板電極７，８の内方側に活物質が残存しない芯材露出部２４が存在しているから、一対の円板電極７，８間に活物質が介在するおそれが全くなく、焼き付きや連続スパークなどが生じることがない。
【００３０】
そのため、円板電極７，８は所要の長寿命を確実に確保することができる。実測結果によると、図１０（ａ）に示すように、芯材露出部３をリードフープ９の接合に必要とする可及的に小さな幅に設定した場合には、円板電極７，８の寿命が72時間であったのに対し、この実施の形態の工程を採用した場合には、円板電極７，８の寿命が1200時間に大幅に延びた。
【００３１】
上述のリードフープ９を接合したのち、圧縮されなかった芯材露出部２４は、（ｇ）に示す幅寄せ圧縮工程において、活物質充填部２２寄りに加圧されて圧縮されることにより、極めて小さな幅とされる。この幅寄せ圧縮工程の詳細については後述する。最後に、（ｈ）に１点鎖線で示す各切断線に沿って打ち抜きおよび裁断されることにより、（ｉ）および図７（ａ）に示すような角形電池用の電極板２８が得られる。この電池用電極板２８は、活物質充填部２８ａと、活物質が除去されたのちに圧縮された集電部２８ｂと、この集電部２８ｂに接合された接続リード部２８ｃとを有しており、幅方向に圧縮された芯材露出部２８ｄは、殆ど無視できる極めて小さな幅になっている。
【００３２】
なお、（ｈ）における打ち抜き加工では、図９（ｃ）に示したトリミングパンチ１０とトリミングダイ１１とを用いてリードフープ９を打ち抜くことにより、リードフープ９を接続リード部２８ｃに成形する。切断加工では、同じく図９（ｃ）に示した切断パンチ１３と切断ダイ１４とを用いて、電池ケース内に収納するときの規格寸法に切断する。
【００３３】
図２（ａ）〜（ｄ）は図１（ｇ）の幅寄せ圧縮工程における加工行程を順に示した縦断面図である。先ず、（ａ）に示す第１の行程では、極板押え２９が上方へ、且つ一対のプッシャ３１が側方へそれぞれ退避した状態において、一対の集電部２７にリードフープ９が接合された被加工物が、図の手前側に向け所定長さ分だけ間欠送りされて支持台３０上の所定位置にセットされる。このとき、両側の一対のリードフープ９は、極板押え２９と支持台３０とからなる幅寄せ治具２６から共に同じ所定長さだけ外方に突出するように設定されている。すなわち、リードフープ９の突出長は、芯材露出部２４の幅よりも僅かに小さく設定されている。
【００３４】
つぎに、（ｂ）に示す第２の行程では、極板押え２９が所定位置まで下降する。このとき、極板押え２９の下段規制面２９ａとリードフープ９との間隙Ｇ１および極板押え２９の中断規制面２９ｂと芯材露出部２４および活物質充填部２２との間隙Ｇ２は、共に0.05〜0.10ｍｍの少許の範囲に設定されている。
【００３５】
続いて、（ｃ）に示す第３の行程では、一対のプッシャ３１が、幅寄せ治具２６に接触する位置まで移動して、外方に突出していた一対のリードフープ９をそれぞれ幅寄せ治具２６内に押し込む。このとき、リードフープ９が接合されている集電部２７は、図１（ｅ）の工程において圧縮されたことによって芯材露出部２４よりも機械的な強度や密度が高められているので、芯材露出部２４を圧縮しながらリードフープ９と一体的に幅寄せ治具２６の内方側へ押し込められる。これにより、図１（ｅ）の工程で圧縮されずに高い空孔率（90％程度）のままの芯材露出部２４は、極めて小さい幅に圧縮される。
【００３６】
このとき、両側のプッシャ３１は対応するリードフープ９を同時に同一の力で同一の距離だけ押圧するので、両側の芯材露出部２４は、中央の活物質充填部２２によって恰も自動調心され、ほぼ同等に圧縮される。また、リードフープ９は、上述のように極板押え２９の下段規制面２９ａに対し0.05〜0.10ｍｍの間隙を有しているから、下段規制面２９ａに曲がり変形するのが防止されながら摺動して円滑に移動する。一方、芯材露出部２４は、極板押え２９の中段規制面２９ｂに対し0.05〜0.10ｍｍの間隙を有しているから、僅かに膨れ上がりながらスムーズに圧縮される。最後に、（ｄ）に示す第４の行程では、極板押え２９が、上述した間隙（0.05〜0.10ｍｍ）分だけ下降しながら芯材露出部２４における圧縮時の上方への膨出部分を加圧して、芯材露出部２４を活物質充填部２２と面一となるよう修正する。
【００３７】
図１の製造工程を経て得られた図７（ａ）の電池用電極板２８は、同図（ｂ）に示す従来の製造工程による電池用電極板１７と比較した場合、活物質充填部２８ａを、芯材露出部２８ｄを圧縮して極めて小さい幅とできる分を見込んで予め大きな体積に設定することができから、活物質量が相当に増大して、それに伴って電池を構成したときの高容量化を図ることができる。
【００３８】
具体的な実測値を示すと、極板幅（図７の横寸法）が15ｍｍ、極板長さ（図７の縦寸法）が31ｍｍ、厚みが0.8 ｍｍの規格値を有する形状の電極板２８，１７を得る場合、従来の電極板１７では芯材露出部３の幅（図７の縦寸法）が1.5 ｍｍであったのに対し、実施の形態の製造工程を経た電極板２８では芯材露出部２８ｄの幅が0.5 ｍｍとなった。これにより、上記実施の形態の製造工程を経て得られた電極板２８では、活物質充填部２８ａの長さ（縦寸法）が１ｍｍ増大して、活物質量が従来の電極板１７に比較して約３％増大した。しかも、十分に大きな幅とした芯材露出部２４のうちの所要幅の部分を圧縮した集電部２８ｂにリードフープ９をシーム溶接工法で接合したのちに芯材露出部２４を圧縮するので、シーム溶接時における焼き付きや連続スパークの発生を確実に防止できる。
【００３９】
また、図１の製造工程では、一連の連続した工程中に幅寄せ圧縮工程が介在するだけであるから、生産性の低下を招くことがなく、それに加えて、特に極板長さの寸法精度の高い電極板２８を得ることができる。この高い寸法精度が得られるのは、図１（ｃ）の工程でプレス加工する際芯材２１とプレスロール（図示せず）との位置ずれ、および図１（ｆ）の工程でリードフープ９を集電部２７に接合した状態での幅Ｗ１に、リードフープ９の位置ずれ、さらに同（ｆ）工程で芯材２１の供給位置ずれなどが発生し易いことに起因して約±0.3 ｍｍの寸法ばらつきが生じるが、同図（ｇ）の幅寄せ圧縮工程において、一対のリードフープ９の外方側端部がプッシャ３１によって図２の幅寄せ治具２６に外側端面に一致するよう押し込められることから、この幅寄せ圧縮工程後の幅Ｗ２が±0.05ｍｍの寸法ばらつきに抑えられるからである。
【００４０】
ところで、図９の製造工程を経て製造された従来の電池用電極板１７では、活物質を正確な幅に管理しながら除去するのが困難であることから、活物質露出部３の幅および活物質露出部３の幅にばらつきが生じ易く、それに応じて活物質充填部２における活物質の重量にばらつきが生じていた。そのため、積層型電極群を構成するに際しては、製造後の電池用電極板１７を重量選別して、ほぼ同じ重量の電池用電極板１７を組み合わせて積層するといった煩雑な工程を必要としていた。
【００４１】
これに対し、上記第１の実施の形態で得られた電池用電極板２８では、図１（ａ）の工程において、凹凸の存在しない芯材２１の全体に活物質を均一に充填でき、（ｇ）の幅寄せ圧縮工程において、両側の芯材露出部２４が中央の活物質充填部２２によって恰も自動調心される状態で圧縮されることにより、リードフープ９の接合位置のばらつきなどが修正されて、上述したように幅寄せ圧縮工程後の幅Ｗ２が±0.05ｍｍの寸法ばらつきに抑えられ、その幅Ｗ２の中央部を切断して２分割したのちに、規定寸法に裁断するので、得られた電極板２８には活物質量のばらつきが極めて少なくなり、従来の重量選別の工程を削減することができるという大きな利点がある。
【００４２】
なお、図１の製造工程では、リードフープ９の接合に先立って、（ｅ）の工程で芯材露出部２４のうちのリードフープを接合するのに必要な所定幅ｄの部分を圧縮して集電部２７を形成するようにしたが、上記（ｅ）の工程は削除してもよい。この場合には、（ｆ）の工程において、リードフープ９を、（ｄ）の工程で形成した芯材露出部２４の所定箇所に直接的に溶接して接合することになるが、図１０で説明したように、リードフープ９の溶接時に、芯材露出部２４におけるリードフープ９が溶接される箇所が、一対の円板電極７，８によって溶接と同時に圧縮されて、集電部２７とされるからである。
【００４３】
また、図１（ｇ）の幅寄せ圧縮工程では、図２（ａ）〜（ｄ）の加工行程を終了したのちに、図３（ｅ）〜（ｆ）に示す加工行程を設けるようにしてもよい。図３において、極板押え２９には、図２に示した箇所に対し後段側箇所、つまり集電部２７にリードフープ９が接合された活物質充填部２２が図２の位置よりも所定長さだけ間欠送りされた位置に対応する後段側箇所に、図２に示した下段規制面２９ａより長い幅の下段規制面２９ｃと、下段規制面２９ｃの幅が長くなった分だけ図２の中段規制面２９ｂよりも幅が短くなった中段規制面２９ｄとが設けられている。上記下段規制面２９ｃは、図２の工程において内方へ押し込められたリードフープ９の内端部に対応する箇所まで延びた大きな幅に設定されている。
【００４４】
図２と図３とに示す支持台３０および極板押え２９は一体物であるから、図３（ｅ）〜（ｈ）の各行程と図２（ａ）〜（ｄ）の各行程とは、それぞれ対応する同一動作状態を示している。この図３（ｅ）〜（ｈ）の各行程を設ければ、（ｅ）に示すように、図２の各行程を終えたのちに、芯材露出部２４の一部にリープフープ９の上方への突出部２４ａが形成されても、この突出部２４ａは、（ｆ）の行程において、極板押え２９が下降した時に下段規制面２９ｃによってリードフープ９の内端面上に押し付けられたのちに、（ｈ）の行程において、極板押え２９がリードフープ９に接触する位置までさらに下降したときに、内部側に押し戻され、僅かな一部がリードフープ９上に薄く押し広げられる。これにより、残存する芯材露出部２４は所要の形状に確実に整形できる。
【００４５】
図４は本発明の第２の実施の形態に係る電池用電極板の製造方法を具現化した製造工程を順に示した斜視図である。この実施の形態においても、積層型電極群を構成して角形電池に用いる電池用電極板を製造する場合を例示してあり、（ａ）〜（ｆ）の各工程は図１と同様であるので、その説明を省略する。（ｇ）の工程では、芯材露出部２４を幅寄せ圧縮しない状態において、１点鎖線で示す各切断線に沿って打ち抜きおよび切断することにより、（ｈ）に示すように、後工程を経て個々の電極板となる電極板素体３２に分割する。
【００４６】
上記電極板素体３２は、第１の実施の形態で得られた電池用電極板２８と同様の活物質充填部２８ａと集電部２８ｂと接続リード部２８ｃとを備えているので、上記電極板２８との関連を明確にして理解を容易にするために、同一の符号を付してあり、芯材露出部２４のみが幅寄せ圧縮されずにそのまま残存している。そこで、各電極板素体３２には、（ｉ）の工程において各々の芯材露出部２４に対し幅寄せ圧縮加工を施すことにより、幅が極めて小さい芯材露出部２８ｄに成形して、第１の実施の形態と同様の電池用電極板２８とされる。なお、図４の工程において、（ｅ）の工程を削除しても支障が生じないのは、図１の工程で説明した通りである。
【００４７】
図５（ａ）〜（ｄ）は図４（ｉ）の幅寄せ圧縮工程における加工行程を順に示した縦断面図である。この幅寄せ圧縮工程に用いられる幅寄せ治具３３は、一端側にストッパ壁面部３７を有する支持台３４と、単一の下段規制面３８ａと一対の中段規制面３８ｂを有する極板押え３８とを備えている。先ず、（ａ）に示す第１の行程では、極板押え３８が上方へ、且つプッシャ３１が側方へそれぞれ退避下状態において、所定個数の電極板素体３２が、図の手前側に送給されて、各々の活物質充填部２８ａの端面をストッパ壁面部３７に当接した状態で支持台３４上の所定位置にセットされる。このとき、リードフープ９は、支持台３４から所定長さだけ外方に突出されている。
【００４８】
つぎに、（ｂ）に示す第２の行程では、極板押え３８が所定位置まで下降する。このとき、第１の実施の形態と同様に、極板押え３８の下段規制面３８ａとリードフープ９との間隙および極板押え３８の中断規制面３８ｂと芯材露出部２４との間隙は、共に0.05〜0.10ｍｍの範囲に設定されている。
【００４９】
続いて、（ｃ）に示す第３の行程では、プッシャ３１が、幅寄せ治具３３に接触する位置まで移動して、外方に突出していたリードフープ９を幅寄せ治具３３内に押し込む。このとき、リードフープ９が接合されている集電部２７は、図４（ｅ）の工程において圧縮されたことによって芯材露出部２４よりも機械的な強度や密度が高められているので、芯材露出部２４を圧縮しながらリードフープ９と一体的に幅寄せ治具３３の内方側へ押し込められる。これにより、図１（ｅ）の工程で圧縮されずに高い空孔率（90％程度）のままの芯材露出部２４は、圧縮されて、極めて小さい幅の芯材露出部２８ｄとなる。このとき、リードフープ９は、上述のように極板押え３８の下段規制面３８ａに対し0.05〜0.10ｍｍの間隙を有しているから、下段規制面３８ａに曲がり変形するのが防止されながら摺動して円滑に移動する。一方、芯材露出部２８ｄは、極板押え３８の中段規制面３８ｂに対し0.05〜0.10ｍｍの間隙を有しているから、僅かに膨れ上がりながらスムーズに圧縮される。
【００５０】
最後に、（ｄ）に示す第４の行程では、極板押え３８が上述した間隙（0.05〜0.10ｍｍ）分だけ下降して、芯材露出部２８ｄにおける圧縮時の上方への膨出部分を加圧して芯材露出部２８ｄを活物質充填部２８ａと面一となるよう修正する。これにより、第１の実施の形態と同様の電池用電極板２８が出来上がる。この電極板２８は、極板押え３８が上方へ、且つプッシャ３１が側方へそれぞれ退避したのちに取り出され、以後、上述と同様の加工動作が繰り返される。したがって、この実施の形態の製造方法は、第１の実施の形態の製造方法に対し一部の工程が入れ替わるだけであり、第１の実施の形態において説明したと同様の効果を確実に得ることができるとともに、第１の実施の形態と同様の電池用電極板２８を得ることができる。
【００５１】
なお、図４（ｉ）の幅寄せ圧縮工程では、図５（ａ）〜（ｄ）の加工行程を終了したのちに、図３（ｅ）〜（ｆ）に示した加工行程に相当する加工工程を行って芯材露出部２８ｄの形状を整形するようにすれば、一層好ましい。
【００５２】
上記第１および第２の実施の形態では、角形電池用の電極板２８の製造について説明したが、本発明の製造方法は、円筒形電池に用いる渦巻状電極群用の電極板の製造にも適用することができる。例えば、図１の（ａ）〜（ｅ）の各工程を経たのち、両側の集電部２７上にこれと同幅のリードフープ９をシーム溶接し、同図（ｆ）に２点鎖線で示す切断線で切断して活物質充填部２２を２分割することにより、図８（ａ）に示すような形状とする。つぎに、図５の幅寄せ治具３３とほぼ同様の幅寄せ治具を用いて芯材露出部２４を極めて小さい幅になるよう圧縮したのちに、所定の長さに切断することにより、図８（ｂ）に示すような円筒形電池用の電極板３９を得ることができる。なお、リードフープ９をシーム溶接したのちに、図２に示した幅寄せ治具２６と同様の幅寄せ治具を用いて芯材露出部２４を予め幅寄せ圧縮し、そののちに裁断するようにしてもよいのは勿論である。
【００５３】
上記円筒形電池の渦巻状電極群用の電極板３９は、芯材露出部２４を圧縮して極めて小さい幅とできる分だけ活物質充填部２２の体積を大きく設定することができるので、活物質量の増大に伴って電池を構成したときの高容量化を図ることができる。また、上記電極板３９は、芯材露出部２４を極めて小さな幅に圧縮することにより、極板幅のばらつきが格段に低減して高い寸法精度を得ることができるとともに、凹凸の存在しない芯材の全体に活物質を均一に充填して所要の工程を経たのちに規定寸法に裁断するので、活物質量のばらつきも極めて少なくなる。
【００５４】
図６は本発明の第３の実施の形態に係る電池用電極板の製造方法を具現化した製造工程の一部を示した縦断面図である。この実施の形態では、積層型電極群を構成して角形電池に用いる電池用電極板を製造する場合を例示してあり、図４（ａ）〜（ｈ）と同様の工程を経て、正極用の電極板素体３２を形成する。つぎに、図６（ａ）に示すように、積層型電極群を構成するのに必要な枚数の電極板素体３２と負極側電極板４１とをそれらの間にセパレータ４０を介在して重ね合わせ、その積層状態で幅寄せ治具４２の支持台４３上に載置し、且つ両側から一対の極板押え４４で挟持して固定する。
【００５５】
続いて、同図（ｂ）に示すように、各電極板素体３２の各々の接続リード部２８ｃは、幅寄せ治具４２側に近接移動するプッシャ３１によって下方に押圧される。これにより、芯材露出部２４は、上記各実施の形態と同様に、接続リード部２８ｃからの押圧力を集電部２８ｂを介し受けて圧縮されて、極めて小さい幅に縮小される。これにより、電極板素体３２は所要形状の正極側電極板２８とされ、それと同時に、正極側電極板２８と負極側電極板４１とがそれらの間にセパレータ４０を介在して積層されてなる角形電池用の電極群４７が出来上がる。したがって、この電極群４７は、そのまま角形電池用の電池ケース内に収納することができるので、角形電池の生産性の向上を図ることができる。
【００５６】
なお、上記幅寄せ治具４２に代えて、図６（ａ）の積層状態とした電極板素体３２、負極側電極板４１およびセパレータ４０を電池ケース内に直接挿入して、その状態で同図（ｂ）に示すようにプッシャ３１で各接続リード部２８ｃを押圧して芯材露出部２４を圧縮することもでき、この場合には角形電池の生産性の一層の向上を図ることができる。
【００５７】
また、図８の円筒形電池用の電極板３９の製造に際しても、図６と同様の製造工程を用いることができる。すなわち、図８（ａ）に示す状態としたものを所定の極板長さ（図の左右方向の長さ）に切断して電極板素体とし、この正極側の電極板素体と負極側電極板とをこれらの間にセパレータを介在して重ね合わせた状態で渦巻き状に巻回して、その巻回状態で幅寄せ治具または円筒形の電池ケース内に挿入する。そののち、プッシャでリードフープおよび集電部を押圧して芯材露出部を圧縮させれば、正極側の電極板３９の形成と同時に円筒形電池用の電極群を構成することができる。
【００５８】
【発明の効果】
以上のように本発明の電池用電極板の製造方法によれば、活物質充填部を、後工程で芯材露出部を圧縮して極めて小さい幅とできる分を見込んで予め大きな体積に設定することができから、活物質量が相当に増大する。また、十分に大きな幅とした芯材露出部のうちの所要幅の部分を圧縮した集電部にリードフープを溶接により接合したのちに芯材露出部を圧縮するので、溶接時における焼き付きや連続スパークの発生を確実に防止して、溶接に用いる電極などの長寿命化を図ることができる。さらに、一連の連続した製造工程中に幅寄せ圧縮工程が介在するだけであるから、生産性の低下を招くことがない。また、リードフープを接合した状態でのリードフープの位置ずれなどに起因する寸法ばらつきを、幅寄せ圧縮工程において芯材露出部の幅を縮小するときに修正できるから、高い寸法精度を得ることができる。
【００５９】
また、本発明の電池用電極板によれば、芯材露出部の幅を圧縮して小さくできる分だけ活物質量を増大できるので、電池を構成したときの高容量化を図ることができる。
【図面の簡単な説明】
【図１】（ａ）〜（ｉ）は本発明の第１の実施の形態に係る電池用電極板の製造方法を具現化した製造工程を順に示した斜視図。
【図２】（ａ）〜（ｄ）は図１（ｇ）の幅寄せ圧縮工程における前半の加工行程を順に示した縦断面図。
【図３】（ｅ）〜（ｈ）は図１（ｇ）の幅寄せ圧縮工程における後半の加工行程を順に示した縦断面図。
【図４】（ａ）〜（ｉ）は本発明の第２の実施の形態に係る電池用電極板の製造方法を具現化した製造工程を順に示した斜視図。
【図５】（ａ）〜（ｄ）は図４（ｉ）の幅寄せ圧縮工程における加工行程を順に示した縦断面図。
【図６】（ａ），（ｂ）は本発明の第３の実施の形態に係る電池用電極板の製造方法を具現化した一部の製造工程を示す縦断面図。
【図７】（ａ）は同上の製造方法により製造された電池用電極板を示す斜視図、（ｂ）は比較のために示した従来の製造方法による電池用電極板の斜視図。
【図８】（ａ）は本発明の製造方法を円筒形電池用電極板に適用した場合の製造過程の斜視図、（ｂ）は製造完了した電極板の斜視図。
【図９】（ａ１），（ａ２），（ｂ），（ｃ）は従来の電池用電極板の製造方法による製造工程を工程順に示した斜視図。
【図１０】（ａ），（ｂ）は同上の製造方法による問題点を説明するための一工程の断面図。
【符号の説明】
９リードフープ
２１芯材
２２活物質充填部
２４芯材露出部
２６，３３，４２幅寄せ治具
２７集電部
２８，３９電池用電極板（正極側電極板）
２９，３８，４４極板押え
２９ａ〜２９ｄ，３８ａ，３８ｂ規制面
３０，３４，４３支持台
３２電極板素体
４０セパレータ
４１負極側電極板[0001]
BACKGROUND OF THE INVENTION
The present invention is, for example, a battery electrode plate that constitutes a power generation element together with an electrolyte in a secondary battery such as a nickel metal hydride storage battery, a nickel cadmium storage battery, and a lithium ion storage battery. The present invention relates to a method for producing a non-sintered battery electrode plate in which an active material is filled in a core material.
[0002]
[Prior art]
As the electrode plate of the secondary battery, a foam metal having a continuous three-dimensional network structure having a high porosity is used as a core material, and the core material is filled with an active material. Widely adopted because of its superiority. Furthermore, recent batteries are strongly required to improve high-rate discharge characteristics, and the following configuration is adopted as a countermeasure.
[0003]
In other words, the battery electrode plate with improved high-rate discharge characteristics forms a core material exposed portion in which the active material that has been filled is removed at a location along one side of the active material filled portion in which the core material is filled with the active material. In addition, the core exposed portion is compressed before filling or removing the active material to reduce the porosity, thereby forming a current collecting portion, and connecting lead portions to the current collecting portion by welding And
[0004]
The rectangular battery electrode group is configured by alternately stacking positive and negative electrode plates having the current collectors with a separator interposed therebetween. On the other hand, the cylindrical battery electrode group is formed by winding a positive and negative electrode plate having the current collecting portion in a spiral shape with a separator interposed therebetween. Therefore, in any electrode group, a plurality of positive / negative current collectors having connection lead portions bonded to both ends are formed over the entire circumference, so by connecting a current collector plate to the connection lead portions on both ends. It is possible to collect current from each electrode plate individually or from the entire circumference of the spiral shape, thereby improving the overall current collection efficiency. In addition, since the current collector is in a state suitable for welding the connection lead portion with the metal core material exposed, the current collector is collected by a tabless method in which a current collector plate or the like is joined to the connection lead portion by welding. The electrical characteristics can be remarkably improved, and the above-described demand for improving the high rate discharge characteristics can be met.
[0005]
The battery electrode plate capable of improving the high-rate discharge characteristics as described above is manufactured, for example, through a process as shown in FIG. 9 (see JP 2000-315498 A). First, in the first step shown in FIG. 2A1, a core 1 having a three-dimensional structure such as foam metal is provided with a dent along both sides, and twice the dent in parallel to the dent. A plurality of groove portions having a groove width of 2 mm are formed through a press molding or compression process. Next, the entire core material 1 including the recess and the groove is filled with an active material in the form of a slurry or a paste, and subsequently the active material adhering to the recess and the groove is used with a brush and an air blow, respectively. After the core material 1 is exposed by removing by the above-mentioned means, the active material is dried, thereby forming the active material filling portion 2 and the core material exposed portion 3 at locations corresponding to the recesses and the groove portions. . Next, the core material exposed part 3 corresponding to the groove part is cut along a cutting line indicated by a broken line at the center of the groove width, so that the core material is formed at both end parts along the longitudinal direction of the band-shaped active material filling part 2. An electrode plate hoop 4 having an exposed portion 3 is manufactured.
[0006]
In the second step shown in FIG. 5B, a pair of upper and lower circles are formed on the core exposed portion 3 of the electrode plate hoop 4 that has been compressed by passing between a pair of compression rolls (not shown). A lead hoop 9, which is a strip metal plate, is joined by a seam welding method using the plate electrodes 7 and 8.
[0007]
In the third step shown in FIG. 6C, the lead hoop 9 is formed into the connection lead portion 12 by punching the lead hoop 9 using the trimming punch 10 and the trimming die 11. The electrode plate hoop 4 formed with the connection lead 12 is housed in the battery outer can using the cutting punch 13 and the cutting die 14 while being intermittently fed by a distance corresponding to the electrode plate width of the electrode plate to be manufactured. Cut to standard dimensions when. As a result, as shown in FIG. 7B, a rectangular battery electrode plate 17 having the connection lead portion 12 at one end of the active material filling portion 2 is completed. The electrode plate for the cylindrical battery is manufactured through substantially the same process as described above, and the difference from that for the square battery is that the length of the connection lead portion is longer than the electrode plate width for the square battery. Just cut it off.
[0008]
Further, conventionally, instead of the first step of FIG. 9A1, a step shown in FIG. 9A2 may be employed. In the step (a2), the core material 1 is filled with the active material and then subjected to a rolling process, thereby forming the active material filling portion 2 over the whole, and at the edge of the active material filling portion 2. By applying ultrasonic vibration having a large amplitude from the ultrasonic horn head 18 for the purpose of completely removing the active material at predetermined locations along the surface, the active material is removed while peeling off, thereby exposing the core material. 3 is formed. (See JP 2000-77054 A).
[0009]
[Problems to be solved by the invention]
However, in the above-described conventional manufacturing method, the width D of the core material exposed portion 3 needs to be set large as shown in FIG. 7B for the reason described later, and the large width D of the core material exposed portion 3 is required. There is a problem that the volume of the active material filling portion 2, that is, the amount of the active material per unit volume is reduced by that amount, and the capacity cannot be increased when the battery is configured.
[0010]
That is, when the core material exposed portion 3 is set to a width d as small as possible necessary for joining the lead hoop 9, for example, as shown in FIG. 10 (a), the upper and lower disk electrodes 7, When the lead hoop 9 is joined to the core material exposed portion 3 by the seam welding method according to FIG. 8, a part of the active material in the vicinity of the core material exposed portion 3 in the active material filling portion 2 is between the disc electrodes 7 and 8. There is a risk of getting in. Since the active material entering from the active material filling portion 2 between the disc electrodes 7 and 8 has a large electric resistance, a spark is generated, and the disc electrodes 7 and 8, the lead hoop 9 and the core material exposed portion 3 Any or all of these will melt. As a result, seizure, continuous spark, and the like occur in the welded portion, causing a problem that continuous seam welding cannot be performed. In addition, since the disk electrodes 7 and 8 are consumed by the generated spark, the required life cannot be ensured.
[0011]
Therefore, conventionally, as shown in FIG. 2B, the core material exposed portion 3 is set to a sufficiently large width D so as to surely prevent the occurrence of the above-mentioned seizure or continuous spark. In connection with this, the amount of active material per unit volume of the conventional electrode plate 17 is reduced, which is a factor that hinders the increase in capacity when a battery is configured. The core material exposed portion 3 has a case where a portion to which the lead hoop 9 is to be bonded is compressed in advance prior to the bonding of the lead hoop 9, and as indicated by a two-dot chain line in FIGS. 10 (a) and 10 (b). The lead hoop 9 may be compressed at the same time as the lead hoop 9 is welded by the pair of disc electrodes 7 and 8 when the lead hoop 9 is joined.
[0012]
On the other hand, the process of FIG. 9 (a2) is intended to form a core material exposed portion 3 having a small width while completely removing the active material. If the width is set small, application of ultrasonic vibration becomes unstable, and the active material remains in the formed core material exposed portion 3. Therefore, it is inevitably necessary to peel off a large amount of the active material. Consequently, the formed core material exposed portion 3 becomes wider in the same manner as in the case of using the step (a1), and is the same as described above. Problem arises.
[0013]
Therefore, the present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a manufacturing method capable of manufacturing a battery electrode plate having a large amount of active material per unit volume without any problem.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, a method of manufacturing a battery electrode plate according to a first aspect of the present invention includes an active material filling step of filling an active material into a whole thin plate-like core material having a porous structure, and the active material comprises: An active material removing step of forming a strip-shaped core material exposed portion from which the active material has been removed along the active material filling portion by applying ultrasonic vibration along the edge portion of the filled active material filling portion; A lead hoop joining step in which a lead hoop is joined by welding to a predetermined location along a peripheral edge portion in the core material exposed portion, and a location where the lead hoop is not joined in the core material exposed portion is the active material filling portion. A width-compressing step for compressing while pressing toward a minimum width, and a cutting step for cutting the active material filling portion and the lead hoop into a predetermined size and dividing them into individual battery electrode plates. It is characterized by that.
[0015]
In this method of manufacturing an electrode plate for a battery, the active material filling portion can be set in advance to a large volume in anticipation of a very small width by compressing the core material exposed portion in a subsequent process. Increases considerably. In addition, after the lead hoop is joined by welding to the part of the required width of the core exposed part that has a sufficiently large width, the core exposed part is compressed to a small width, so seizure and continuous sparking occur during welding. Can be reliably prevented, and the life of electrodes and the like used for welding can be extended. Furthermore, since the width-shifting compression process is merely interposed in a series of continuous manufacturing processes, productivity is not reduced. In addition, dimensional variations caused by misalignment of the lead hoop in a state where the lead hoop is joined can be corrected when the width of the exposed portion of the core material is reduced in the width-shifting compression process, so that high dimensional accuracy can be obtained. it can.
[0016]
According to a second aspect of the present invention, there is provided a method of manufacturing a battery electrode plate comprising: an active material filling step of filling an active material into a whole thin plate-like core material having a porous structure; and an active material filling portion filled with the active material. An active material removing step of forming a strip-shaped core material exposed portion from which the active material has been removed by applying ultrasonic vibration along the edge portion along the active material filling portion; and a side in the core material exposed portion. A lead hoop joining process in which a lead hoop is joined to a predetermined location along the edge by welding, and the active material filling portion, the core material exposed portion, and the lead hoop are cut into specified dimensions and divided into individual electrode plate bodies. Each electrode plate element is compressed to a minimum width while pressing a portion where the lead hoop of the core material exposed portion of each electrode plate element body is not joined to the active material filling portion in the cutting step. Alignment compression with body as electrode plate It is characterized in that it has and.
[0017]
In this battery electrode plate manufacturing method, as in the first aspect of the invention, the active material filling portion is set in advance to a large volume in anticipation of an extremely small width by compressing the core material exposed portion in a subsequent process. The amount of active material increases considerably. Also, since the core material exposed part is compressed after joining the lead hoop to the current collector part where the required width part of the core material exposed part having a sufficiently large width is compressed, seizure and continuous It is possible to reliably prevent the occurrence of sparks and extend the life of electrodes used for welding. Furthermore, since the width-shifting compression process is merely interposed in a series of continuous manufacturing processes, productivity is not reduced. In addition, dimensional variations caused by misalignment of the lead hoop in a state where the lead hoop is joined can be corrected when the width of the exposed portion of the core material is reduced in the width-shifting compression process, so that high dimensional accuracy can be obtained. it can.
[0018]
In the width-shifting compression step according to the second aspect of the invention, the positive-side or negative-side electrode plate element and the negative-side or positive-side electrode plate are overlapped with a separator interposed between them. After fixing to the inside of the tool or the battery case, the portion where the lead hoop of the core material exposed portion of the electrode plate body is not joined may be compressed to a minimum width while being pressed toward the active material filling portion. it can.
[0019]
Thereby, the electrode plate body can be formed into an electrode plate having a required shape by compressing and reducing the width of the exposed portion of the core material, and at the same time, an electrode group for a prismatic battery or a cylindrical battery can be configured. Therefore, it is possible to further improve the productivity of the battery.
[0020]
In each of the above inventions, a lead hoop is welded to a predetermined location along the edge portion of the core material exposed portion formed through the active material removing step, and the lead hoop of the core material exposed portion is bonded. By compressing the joining location before or during joining to a current collecting part, and applying a pressing force applied to the lead hoop to the remaining core exposed part in the width-shifting compression process via the current collecting part, It is preferable that the core exposed portion is pressed and compressed closer to the active material filling portion.
[0021]
As a result, the current collecting part to which the lead hoop is joined has a higher mechanical strength and density than the remaining exposed part of the core material. The remaining core exposed portion can be easily and reliably compressed by moving integrally with the lead hoop.
[0022]
In the width-shifting compression process as described above, the active material filling portion is placed on the support base in an arrangement in which a predetermined length of the lead hoop protrudes outward, and two regulations protruding in two stages in the electrode plate presser With the surface facing the lead hoop and the active material filling portion and the core material exposed portion with a small gap, after pushing the protruding portion from the support base in the lead hoop closer to the support base, It is preferable that the electrode plate holder is moved closer to the support base by the gap.
[0023]
As a result, the lead hoop has a small clearance with respect to the regulating surface of the electrode plate holder, and thus slides and moves smoothly while being prevented from being bent and deformed on the regulating surface. On the other hand, the core material exposed portion has a small clearance with respect to the regulating surface of the electrode plate holder, and is thus compressed smoothly while slightly swollen. After that, when the electrode plate presser moves closer to the support base by the gap, the bulging part at the time of compression in the core material exposed part is pressurized so that the core material exposed part is flush with the active material filling part. It can be corrected as follows.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view sequentially illustrating manufacturing steps embodying a method for manufacturing a battery electrode plate according to a first embodiment of the present invention. In this embodiment, a case where a laminated electrode group is configured to manufacture a battery electrode plate used for a rectangular battery is illustrated.
[0026]
First, the active material filling portion 22 is formed by filling the entire core material 21 made of a rectangular or belt-shaped three-dimensional foam metal having a predetermined size shown in (a), as shown in (b). When the active material filling portion 22 is formed, the active material is filled into the core material 21 that is not pressed and has no unevenness, so that the entire material can be filled with a uniform filling density and there is no unevenness, that is, no difference in height. Therefore, the filled active material is held inside without flowing and dried while maintaining a uniform packing density. On the other hand, in the process of FIG. 9A1 according to the conventional manufacturing method, the active material is filled into the core material 1 in which the dents and the grooves are formed in advance through the press molding or rolling process. As a result, the packing density of the active material varies.
[0027]
Next, as shown in (c), the core material 21 in which the active material filling portion 22 having a uniform filling density as described above is formed on all portions except the portion that becomes the core material exposed portion in the subsequent process. By being pressed, it is compressed to approximately ½, and the portion that becomes the core material exposed portion in the subsequent process remains as two parallel rail-shaped remaining ridges 23. Although not shown in the drawing, the basic structure is the same as that of the stripe roll press shown in FIG. 2 in Japanese Patent Application No. 2000-261471 filed by the applicant of the present application. A stripe roll press provided in an arrangement is used.
[0028]
Subsequently, in the active material removing step shown in (d), the two remaining ridge portions 23 are removed from the active material filling portion 22 filled therein, thereby the two core material exposed portions 24. It is said. In this active material removing step, an active material removing device (not shown) having the same configuration as that of the active material removing device including the ultrasonic vibrator shown in FIG. 4 in Japanese Patent Application No. 2000-261471 described above is used. Processed. The width D of the core material exposed portion 24 here is set to be larger than a predetermined width necessary for joining the lead hoops in a later process. As a result, the ultrasonic vibrator can be applied with ultrasonic vibration set to a sufficiently large amplitude, and the core is completely removed without remaining the active material regardless of the degree of binding of the active material. The material exposed portion 24 can be formed.
[0029]
Next, as shown in (e), the portion of the predetermined width d necessary for joining the lead hoops in each core material exposed portion 24 is compressed by a press roll (not shown) and remains. The current collector 27 is one step lower than the original core exposed portion 24. Subsequently, as shown in (f), the lead hoop 9 is joined to the current collector 27 by a seam welding method using a pair of disk electrodes 7 and 8 similar to those shown in FIG. This lead hoop 9 is seam welded to a current collecting portion 27 formed by compressing a part of the core material exposed portion 24 set to a sufficiently large width D and from which the active material is completely removed, and a pair of discs Since the core material exposed portion 24 where no active material remains is present on the inner side of the electrodes 7 and 8, there is no possibility that the active material is interposed between the pair of disk electrodes 7 and 8, and seizure or continuous sparking occurs. Etc. will not occur.
[0030]
Therefore, the disk electrodes 7 and 8 can ensure the required long life. According to the measurement result, as shown in FIG. 10A, when the core material exposed portion 3 is set to the smallest possible width necessary for joining the lead hoop 9, the disk electrodes 7 and 8 Whereas the lifetime was 72 hours, when the process of this embodiment was adopted, the lifetime of the disk electrodes 7 and 8 was greatly extended to 1200 hours.
[0031]
After joining the lead hoop 9 described above, the core material exposed portion 24 that has not been compressed is compressed by being compressed toward the active material filling portion 22 in the width-shifting compression step shown in FIG. A small width. Details of this width-compressing compression step will be described later. Finally, by punching and cutting along each cutting line indicated by a one-dot chain line in (h), an electrode plate 28 for a rectangular battery as shown in (i) and FIG. 7 (a) is obtained. The battery electrode plate 28 includes an active material filling portion 28a, a current collecting portion 28b compressed after the active material is removed, and a connection lead portion 28c joined to the current collecting portion 28b. The core material exposed portion 28d compressed in the width direction has an extremely small width that is almost negligible.
[0032]
In the punching process in (h), the lead hoop 9 is punched out using the trimming punch 10 and the trimming die 11 shown in FIG. 9C, thereby forming the lead hoop 9 into the connection lead portion 28c. In the cutting process, the cutting punch 13 and the cutting die 14 similarly shown in FIG. 9C are used to cut to the standard dimensions when housed in the battery case.
[0033]
2 (a) to 2 (d) are longitudinal sectional views sequentially showing the processing steps in the width-shifting compression step of FIG. 1 (g). First, in the first step shown in (a), the lead hoop 9 is joined to the pair of current collectors 27 in a state where the electrode plate retainer 29 is retracted upward and the pair of pushers 31 are retracted sideways. The workpiece is intermittently fed by a predetermined length toward the near side of the figure and set at a predetermined position on the support base 30. At this time, the pair of lead hoops 9 on both sides are set to project outward by the same predetermined length from the width adjusting jig 26 including the electrode plate holder 29 and the support base 30. That is, the protruding length of the lead hoop 9 is set slightly smaller than the width of the core material exposed portion 24.
[0034]
Next, in the second stroke shown in (b), the electrode plate holder 29 is lowered to a predetermined position. At this time, the gap G1 between the lower regulation surface 29a of the electrode plate holder 29 and the lead hoop 9 and the gap G2 between the interruption regulation surface 29b of the electrode plate holder 29 and the core material exposed portion 24 and the active material filling portion 22 are both 0.05. It is set in the range of less than 0.10mm.
[0035]
Subsequently, in the third step shown in FIG. 3C, the pair of pushers 31 moves to a position where they come into contact with the width adjusting jig 26, and the pair of lead hoops 9 protruding outward are respectively subjected to the width adjusting treatment. Push into tool 26. At this time, the current collecting portion 27 to which the lead hoop 9 is joined has a higher mechanical strength and density than the core exposed portion 24 by being compressed in the step of FIG. While compressing the core material exposed portion 24, it is pushed into the inner side of the width adjusting jig 26 integrally with the lead hoop 9. As a result, the core material exposed portion 24 that remains high in porosity (about 90%) without being compressed in the step of FIG. 1E is compressed to an extremely small width.
[0036]
At this time, since the pushers 31 on both sides simultaneously press the corresponding lead hoops 9 with the same force for the same distance, the core material exposed portions 24 on both sides are also automatically centered by the central active material filling portion 22, Compressed almost equally. Since the lead hoop 9 has a gap of 0.05 to 0.10 mm with respect to the lower regulation surface 29a of the electrode plate retainer 29 as described above, the lead hoop 9 slides while being prevented from being bent and deformed to the lower regulation surface 29a. And move smoothly. On the other hand, since the core material exposed portion 24 has a gap of 0.05 to 0.10 mm with respect to the middle regulation surface 29b of the electrode plate retainer 29, it is smoothly compressed while slightly swollen. Finally, in the fourth step shown in (d), the electrode plate presser 29 is lowered by an amount corresponding to the gap (0.05 to 0.10 mm) described above, and an upward bulging portion at the time of compression in the core material exposed portion 24 is removed. The core material exposed portion 24 is corrected to be flush with the active material filling portion 22 by applying pressure.
[0037]
The battery electrode plate 28 of FIG. 7A obtained through the manufacturing process of FIG. 1 is compared with the battery electrode plate 17 of the conventional manufacturing process shown in FIG. Can be set to a large volume in advance by allowing the core material exposed portion 28d to be compressed to an extremely small width, so that the amount of the active material is considerably increased and the battery is configured accordingly. High capacity can be achieved.
[0038]
Specifically, the electrode plate 28 having a standard value with an electrode plate width (horizontal dimension in FIG. 7) of 15 mm, an electrode plate length (vertical dimension in FIG. 7) of 31 mm, and a thickness of 0.8 mm is shown. , 17 in the conventional electrode plate 17, the width (vertical dimension in FIG. 7) of the core material exposed portion 3 is 1.5 mm, whereas in the electrode plate 28 that has undergone the manufacturing process of the embodiment, the core material is obtained. The width of the exposed portion 28d was 0.5 mm. Thereby, in the electrode plate 28 obtained through the manufacturing process of the above embodiment, the length (vertical dimension) of the active material filling portion 28a is increased by 1 mm, and the amount of the active material is compared with the conventional electrode plate 17. About 3%. Moreover, since the core material exposed portion 24 is compressed after the lead hoop 9 is joined by the seam welding method to the current collecting portion 28b in which the required width portion of the core material exposed portion 24 having a sufficiently large width is compressed, It is possible to reliably prevent seizure and continuous sparking during seam welding.
[0039]
Further, in the manufacturing process of FIG. 1, since the width-shifting compression process is merely interposed in a series of continuous processes, productivity is not reduced. High electrode plate 28 can be obtained. This high dimensional accuracy can be obtained when the core material 21 and the press roll (not shown) are misaligned during the pressing process in the step of FIG. 1C, and in the lead hoop 9 in the step of FIG. Of the lead hoop 9 and the supply position of the core material 21 in the step (f) are likely to occur in the width W1 in the state in which the current collector 27 is bonded to the current collector 27, and about ± 0.3 mm. However, in the width shifting compression process of FIG. 2G, the outer side ends of the pair of lead hoops 9 are pushed by the pusher 31 so as to coincide with the outer end face of the width shifting jig 26 of FIG. This is because the width W2 after the width-shifting compression process is suppressed to a dimensional variation of ± 0.05 mm.
[0040]
By the way, in the conventional battery electrode plate 17 manufactured through the manufacturing process of FIG. 9, it is difficult to remove the active material while managing the accurate width. Variations in the width of the material exposed portion 3 are likely to occur, and the active material weight in the active material filling portion 2 varies accordingly. Therefore, when configuring the laminated electrode group, a complicated process is required in which the battery electrode plate 17 after manufacture is subjected to weight selection, and the battery electrode plates 17 having substantially the same weight are combined and laminated.
[0041]
On the other hand, in the battery electrode plate 28 obtained in the first embodiment, the active material can be uniformly filled in the entire core material 21 having no irregularities in the step of FIG. In the width-shifting compression process of g), the core material exposed portions 24 on both sides are compressed in a state in which the core is automatically aligned by the central active material filling portion 22, thereby correcting variations in the joining position of the lead hoop 9. Then, as described above, the width W2 after the width-shifting compression process is suppressed to dimensional variation of ± 0.05 mm, and the center portion of the width W2 is cut into two parts and then cut into the specified dimensions. The obtained electrode plate 28 has a great advantage that the variation in the amount of active material is extremely small, and the conventional weight selection process can be reduced.
[0042]
In the manufacturing process of FIG. 1, prior to joining the lead hoop 9, the part of the predetermined width d necessary for joining the lead hoop in the core material exposed portion 24 is compressed in the process (e). Although the current collector 27 is formed, the step (e) may be omitted. In this case, in the step (f), the lead hoop 9 is directly welded and joined to a predetermined portion of the core material exposed portion 24 formed in the step (d). As described above, when the lead hoop 9 is welded, a portion of the core material exposed portion 24 where the lead hoop 9 is welded is compressed simultaneously with the welding by the pair of disk electrodes 7 and 8, thereby forming the current collector 27. This is because that.
[0043]
1 (g), the machining steps shown in FIGS. 3 (e) to (f) are provided after the machining steps of FIGS. 2 (a) to (d) are completed. Also good. In FIG. 3, the electrode plate holder 29 has a portion on the rear side of the portion shown in FIG. 2, that is, an active material filling portion 22 in which the lead hoop 9 is joined to the current collecting portion 27 with a predetermined length from the position in FIG. The lower stage restricting surface 29c having a width longer than the lower stage restricting surface 29a shown in FIG. 2 and the width of the lower stage restricting surface 29c are increased in the rear side portion corresponding to the intermittently fed position. An intermediate regulation surface 29d having a width shorter than that of the regulation surface 29b is provided. The lower regulation surface 29c is set to have a large width extending to a location corresponding to the inner end of the lead hoop 9 pushed inward in the process of FIG.
[0044]
Since the support 30 and the electrode plate retainer 29 shown in FIGS. 2 and 3 are a single body, the strokes of FIGS. 3E to 3H and the strokes of FIGS. These show the same corresponding operating state. If each step of FIG. 3 (e) to (h) is provided, as shown in FIG. 3 (e), after finishing each step of FIG. Even if the protruding portion 24a is formed, the protruding portion 24a is pressed on the inner end surface of the lead hoop 9 by the lower regulating surface 29c when the electrode plate holder 29 is lowered in the process (f). In the process of (h), when the electrode plate holder 29 is further lowered to the position where it contacts the lead hoop 9, it is pushed back to the inner side, and a small part is thinly spread on the lead hoop 9. Thereby, the remaining core material exposed portion 24 can be reliably shaped into a required shape.
[0045]
FIG. 4 is a perspective view sequentially illustrating manufacturing steps embodying the manufacturing method of the battery electrode plate according to the second embodiment of the present invention. Also in this embodiment, a case where a laminated electrode group is configured to manufacture a battery electrode plate used for a rectangular battery is illustrated, and each step (a) to (f) is the same as FIG. Therefore, the description is omitted. In the step (g), the core material exposed portion 24 is punched and cut along each cutting line indicated by a one-dot chain line in a state where the core material exposed portion 24 is not stretched and compressed, and as shown in FIG. The electrode plate body 32 is divided into individual electrode plates.
[0046]
Since the electrode plate body 32 includes the active material filling portion 28a, the current collecting portion 28b, and the connection lead portion 28c similar to the battery electrode plate 28 obtained in the first embodiment, In order to make the relationship with the plate 28 clear and easy to understand, the same reference numerals are given, and only the core exposed portion 24 remains as it is without being compressed. Therefore, each electrode plate element 32 is formed into a core material exposed portion 28d having a very small width by subjecting each core material exposed portion 24 to a width-compressing compression process in the step (i). The battery electrode plate 28 is the same as that of the first embodiment. In the process of FIG. 4, the fact that the process (e) is deleted does not cause any problem as described in the process of FIG.
[0047]
FIGS. 5A to 5D are longitudinal cross-sectional views sequentially showing the processing steps in the width-shifting compression step of FIG. 4I. The width adjusting jig 33 used in this width adjusting compression process includes a support base 34 having a stopper wall surface portion 37 on one end side, and an electrode plate presser 38 having a single lower stage regulating surface 38a and a pair of middle stage regulating surfaces 38b. It has. First, in the first step shown in FIG. 5A, a predetermined number of electrode plate bodies 32 are sent to the front side of the figure in a state where the electrode plate retainer 38 is moved upward and the pusher 31 is retracted sideways. Then, the end surface of each active material filling portion 28a is set at a predetermined position on the support base 34 in a state where the end surface is in contact with the stopper wall surface portion 37. At this time, the lead hoop 9 protrudes outward from the support base 34 by a predetermined length.
[0048]
Next, in the second stroke shown in (b), the electrode plate presser 38 is lowered to a predetermined position. At this time, as in the first embodiment, the gap between the lower regulation surface 38a of the electrode plate retainer 38 and the lead hoop 9 and the gap between the interruption regulation surface 38b of the electrode plate retainer 38 and the core material exposed portion 24 are as follows. Both are set in the range of 0.05 to 0.10 mm.
[0049]
Subsequently, in the third step shown in FIG. 3C, the pusher 31 moves to a position where it comes into contact with the width adjusting jig 33 and pushes the lead hoop 9 protruding outward into the width adjusting jig 33. . At this time, the current collecting portion 27 to which the lead hoop 9 is joined has a higher mechanical strength and density than the core exposed portion 24 by being compressed in the step of FIG. The core material exposed portion 24 is pressed into the inner side of the width adjusting jig 33 integrally with the lead hoop 9 while being compressed. As a result, the core material exposed portion 24 that is not compressed in the step of FIG. 1E and remains high in porosity (about 90%) is compressed into a core material exposed portion 28d having an extremely small width. At this time, since the lead hoop 9 has a gap of 0.05 to 0.10 mm with respect to the lower regulation surface 38a of the electrode plate retainer 38 as described above, the lead hoop 9 is slid while being prevented from being bent and deformed to the lower regulation surface 38a. Move and move smoothly. On the other hand, since the core material exposed portion 28d has a gap of 0.05 to 0.10 mm with respect to the middle regulation surface 38b of the electrode plate presser 38, it is smoothly compressed while slightly swollen.
[0050]
Finally, in the 4th process shown in (d), electrode plate holder 38 descends by the above-mentioned gap (0.05-0.10 mm), and the bulge part to the upper part at the time of compression in core material exposure part 28d is carried out. The core material exposed portion 28d is corrected to be flush with the active material filling portion 28a by applying pressure. Thereby, the battery electrode plate 28 similar to that of the first embodiment is completed. The electrode plate 28 is taken out after the electrode plate retainer 38 is retracted upward and the pusher 31 is retracted laterally. Thereafter, the same processing operation as described above is repeated. Therefore, the manufacturing method of this embodiment only replaces some of the steps with respect to the manufacturing method of the first embodiment, and reliably obtains the same effects as described in the first embodiment. In addition, a battery electrode plate 28 similar to that of the first embodiment can be obtained.
[0051]
4 (i), the processing corresponding to the processing steps shown in FIGS. 3 (e) to 3 (f) is performed after the processing steps of FIGS. 5 (a) to 5 (d) are completed. It is more preferable to perform the process so as to shape the shape of the core exposed portion 28d.
[0052]
In the first and second embodiments, the production of the electrode plate 28 for the square battery has been described. However, the production method of the present invention can also be used to produce the electrode plate for the spiral electrode group used for the cylindrical battery. Can be applied. For example, after passing through the steps (a) to (e) in FIG. 1, lead hoops 9 having the same width are seam welded on the current collecting portions 27 on both sides, and a two-dot chain line in FIG. The active material filling portion 22 is divided into two by cutting along the cutting line shown in FIG. 8 to obtain a shape as shown in FIG. Next, after compressing the core material exposed portion 24 to have a very small width using a width adjusting jig substantially the same as the width adjusting jig 33 of FIG. An electrode plate 39 for a cylindrical battery as shown in FIG. 8B can be obtained. After the lead hoop 9 is seam welded, the core material exposed portion 24 is preliminarily pressed and compressed using a width adjusting jig similar to the width adjusting jig 26 shown in FIG. 2, and then cut. Of course, it may be.
[0053]
The electrode plate 39 for the spiral electrode group of the cylindrical battery can set the volume of the active material filling portion 22 as large as possible by compressing the core material exposed portion 24 so as to have a very small width. The capacity can be increased when the battery is configured as the amount increases. In addition, the electrode plate 39 can compress the core material exposed portion 24 to an extremely small width, thereby greatly reducing variations in the width of the electrode plate and obtaining high dimensional accuracy. Since the active material is uniformly filled in the whole and cut into the prescribed dimensions after a required process, the variation in the amount of the active material is extremely reduced.
[0054]
FIG. 6 is a longitudinal sectional view showing a part of a manufacturing process embodying the manufacturing method of the battery electrode plate according to the third embodiment of the present invention. In this embodiment, a case where a laminated electrode group is formed to produce a battery electrode plate for use in a rectangular battery is illustrated, and the positive electrode is subjected to the same steps as in FIGS. 4A to 4H. The electrode plate body 32 is formed. Next, as shown in FIG. 6 (a), the number of electrode plate base bodies 32 and the negative electrode plate 41 required to form a stacked electrode group are stacked with a separator 40 interposed therebetween. In addition, the laminated state is placed on the support base 43 of the width adjusting jig 42, and sandwiched and fixed by a pair of electrode plate holders 44 from both sides.
[0055]
Subsequently, as shown in FIG. 4B, each connection lead portion 28c of each electrode plate element 32 is pressed downward by a pusher 31 that moves close to the width adjusting jig 42 side. As a result, the core material exposed portion 24 is compressed by receiving the pressing force from the connection lead portion 28c via the current collecting portion 28b as in the above embodiments, and is reduced to a very small width. As a result, the electrode plate element 32 is formed into the required shape of the positive electrode plate 28, and at the same time, the positive electrode plate 28 and the negative electrode plate 41 are laminated with the separator 40 interposed therebetween. The electrode group 47 for a square battery is completed. Therefore, since this electrode group 47 can be accommodated in the battery case for a rectangular battery as it is, the productivity of the rectangular battery can be improved.
[0056]
It should be noted that, instead of the width adjusting jig 42, the electrode plate body 32, the negative electrode plate 41 and the separator 40 in the laminated state shown in FIG. 6A are directly inserted into the battery case, and the same condition is maintained. As shown in FIG. 2B, the core material exposed portion 24 can be compressed by pressing each connection lead portion 28c with the pusher 31, and in this case, the productivity of the rectangular battery can be further improved. .
[0057]
Further, the manufacturing process similar to that shown in FIG. 6 can be used in manufacturing the electrode plate 39 for the cylindrical battery shown in FIG. That is, the state shown in FIG. 8A is cut into a predetermined electrode plate length (length in the left-right direction in the figure) to form an electrode plate element, and the positive electrode plate element and the negative electrode side The electrode plate is wound in a spiral shape with a separator interposed therebetween, and is inserted into a width adjusting jig or a cylindrical battery case in the wound state. After that, if the lead hoop and the current collector are pressed by the pusher to compress the core exposed portion, the electrode group for the cylindrical battery can be formed simultaneously with the formation of the electrode plate 39 on the positive electrode side.
[0058]
【The invention's effect】
As described above, according to the method for manufacturing a battery electrode plate of the present invention, the active material filling portion is set to a large volume in advance in anticipation of an extremely small width by compressing the core material exposed portion in a subsequent process. The amount of active material increases considerably. Also, since the core material exposed part is compressed after joining the lead hoop to the current collector part where the required width part of the core material exposed part having a sufficiently large width is compressed, seizure and continuous It is possible to reliably prevent the occurrence of sparks and extend the life of electrodes used for welding. Furthermore, since the width-shifting compression process is merely interposed in a series of continuous manufacturing processes, productivity is not reduced. In addition, dimensional variations caused by misalignment of the lead hoop in a state where the lead hoop is joined can be corrected when the width of the exposed portion of the core material is reduced in the width-shifting compression process, so that high dimensional accuracy can be obtained. it can.
[0059]
Further, according to the battery electrode plate of the present invention, the amount of the active material can be increased by the amount that the width of the exposed portion of the core material can be reduced, so that the capacity can be increased when the battery is configured.
[Brief description of the drawings]
FIGS. 1A to 1I are perspective views sequentially illustrating manufacturing steps embodying a method for manufacturing a battery electrode plate according to a first embodiment of the present invention.
FIGS. 2A to 2D are longitudinal sectional views sequentially showing the first half of the processing step in the width-shifting compression step of FIG.
FIGS. 3E to 3H are longitudinal cross-sectional views sequentially showing the latter processing steps in the width-shifting compression step of FIG.
FIGS. 4A to 4I are perspective views sequentially illustrating manufacturing steps embodying a method for manufacturing a battery electrode plate according to a second embodiment of the present invention. FIGS.
FIGS. 5A to 5D are longitudinal sectional views sequentially showing processing steps in the width-shifting compression step of FIG. 4I.
FIGS. 6A and 6B are longitudinal sectional views showing a part of the manufacturing process embodying the manufacturing method of the battery electrode plate according to the third embodiment of the present invention. FIGS.
7A is a perspective view showing a battery electrode plate manufactured by the above manufacturing method, and FIG. 7B is a perspective view of a battery electrode plate by a conventional manufacturing method shown for comparison.
8A is a perspective view of a manufacturing process when the manufacturing method of the present invention is applied to an electrode plate for a cylindrical battery, and FIG. 8B is a perspective view of an electrode plate that has been manufactured.
9 (a1), (a2), (b), and (c) are perspective views showing manufacturing steps according to a conventional method of manufacturing a battery electrode plate in order of steps.
FIGS. 10A and 10B are cross-sectional views of one process for explaining problems in the manufacturing method according to the embodiment.
[Explanation of symbols]
9 Lead Hoop
21 Core
22 Active material filling section
24 Core exposed part
26, 33, 42 Alignment jig
27 Current collector
28,39 Battery electrode plate (positive electrode plate)
29, 38, 44 Polar plate presser
29a-29d, 38a, 38b Regulatory surface
30, 34, 43 Support stand
32 Electrode plate body
40 separator
41 Negative electrode plate

Claims

An active material filling step of filling the entire thin plate-like core material having a porous material with an active material, and applying ultrasonic vibration along a peripheral portion of the active material filling portion filled with the active material, An active material removing step of forming a strip-shaped core material exposed portion from which the active material has been removed along the active material filling portion, and a lead hoop is joined to a predetermined location along the edge portion of the core material exposed portion by welding. A lead hoop joining step, a width-compressing compression step in which a portion where the lead hoop in the core material exposed portion is not joined is compressed toward the active material filling portion and compressed to a minimum width, and the active material filling portion And a cutting step of cutting the lead hoop into a predetermined size and dividing the lead hoop into individual battery electrode plates.

An active material filling step of filling the entire thin plate-like core material having a porous material with an active material, and applying ultrasonic vibration along a peripheral portion of the active material filling portion filled with the active material, An active material removing step of forming a strip-shaped core material exposed portion from which the active material has been removed along the active material filling portion, and a lead hoop is joined to a predetermined location along the edge portion of the core material exposed portion by welding. A lead hoop joining step, a cutting step of cutting the active material filling portion, the core material exposed portion, and the lead hoop into predetermined electrode plates and dividing them into individual electrode plate bodies; and the core material exposure in each of the electrode plate bodies And compressing to a minimum width while pressing the part where the lead hoop of the part is not joined toward the active material filling part, and a width-compressing compression step using the electrode plate bodies as electrode plates Battery electrode characterized in that The method of production.

In the width-shifting compression process, the positive electrode-side or negative-electrode side electrode plate body and the negative-electrode-side or positive-electrode side electrode plate are overlapped with a separator interposed therebetween, or inside the width-shifting jig or battery case 3. After being fixed inside, the portion where the lead hoop of the core material exposed portion of the electrode plate body is not joined is pressed toward the active material filling portion and compressed to a minimum width. Of manufacturing a battery electrode plate.

A lead hoop is welded to a predetermined location along the edge portion of the core material exposed portion formed through the active material removing step, and the joint location of the lead hoop in the core material exposed portion is joined. The core material exposed portion is formed by applying a pressing force applied to the lead hoop to the remaining core material exposed portion through the current collector portion in the width-shifting compression process by compressing before or during joining. 4. The method for producing a battery electrode plate according to claim 1, wherein the pressure is compressed near the active material filling portion.

In the width-shifting compression process, the active material filling portion is placed on the support base in an arrangement in which a predetermined length of the lead hoop protrudes outward, and two restriction surfaces protruding in two stages in the electrode plate holder are provided. In a state where the lead hoop is opposed to the active material filling portion and the core material exposed portion with a small clearance, the protruding portion from the support base in the lead hoop is pushed closer to the support base, and then the electrode The manufacturing method of the battery electrode plate according to claim 4, wherein the plate presser is moved close to the support base by the gap.