JP4971561B2

JP4971561B2 - Electrolyte injection method and apparatus

Info

Publication number: JP4971561B2
Application number: JP2001241965A
Authority: JP
Inventors: 昭司唐沢; 道雄大沢; 英雄浅香
Original assignee: Panasonic Corp; Toyota Motor Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Toyota Motor Corp; Panasonic Holdings Corp
Priority date: 2001-08-09
Filing date: 2001-08-09
Publication date: 2012-07-11
Anticipated expiration: 2021-08-09
Also published as: JP2003059485A

Description

【０００１】
【発明の属する技術分野】
本発明は、電池に電解液を注入する方法及び装置に関するものである。
【０００２】
【従来の技術】
ニッケル・水素電池やリチウムイオン電池や鉛蓄電池など、正極板と負極板をセパレータを介して積層して成る極板群と電解液を電槽に収容されている電池において、電解液を電槽に注入する際には、極板群、特にそのセパレータの全体に電解液を十分に含浸させる必要があるが、極板群は積層構造であるため、電槽内に単純に電解液を注入しても、電解液を所望の生産性が得られる速度で全体に均等に含浸させることはできない。
【０００３】
そこで従来から、例えば特開平９−２８３１１４号公報や、特開平１１−３３９７７０号公報などに開示されているように、電槽内に電解液を注入する注液工程と、所定の真空圧となるように減圧して電解液を含浸させ、その後大気に戻すことにより電解液を加圧してさらに含浸させる脱気工程とを適宜に組み合わせた注入方法が提案されている。
【０００４】
特開平９−２８３１１４号公報では、容器内に電解液を供給する工程と容器内を減圧雰囲気にして容器内に含有する気体を吸引除去する脱気工程と電解液を加圧して吸収させる加圧工程とを備えた注入方法が開示されている。
【０００５】
特開平１１−３３９７７０号公報では、注液工程の後、減圧下で電解液を含浸させる工程を複数回繰り返すとともに、後の減圧処理工程の真空圧力を高くする方法が開示されている。
【０００６】
【発明が解決しようとする課題】
ところで、上記従来の注入方法によって電解液の注入を生産性良く行うためには、注液及び脱気を速やかに行えるように電槽の開口を大きくし、また所定の真空圧力に達するまでの減圧時間を短縮して脱気工程の時間を短縮するのが効果的である。しかしながら、電槽の開口を大きくしかつ減圧時間を短縮すると、脱気工程時に極板群内に含有していた空気が勢い良く吹き上げ、その気流によって先に注入されていた電解液が周囲に飛び散ってしまう恐れがある。
【０００７】
電解液が飛び散ると、電池性能に大きく影響するために厳しく管理すべき電解液量にばらつきを生じてしまうという問題があり、また電解液が電槽の開口に付着し、その開口を溶着等によって封止する際に悪影響を与え、信頼性の高い密閉が困難になるという問題がある。
【０００８】
本発明は、上記従来の問題点に鑑み、極板群が収容された電槽に対して電解液を生産性良くかつ他に弊害を生じることなく注入することができる電解液注入方法及び装置を提供することを目的とする。
【０００９】
【課題を解決するための手段】
本発明の電解液注入方法は、正極板と負極板をセパレータを介して積層もしくは巻回して成る極板群が収容されている電槽内に電解液を注入する際に、電解液を電槽に注入する注液工程と、電槽を脱気ボックス内に配置して脱気した後大気開放する脱気工程とを有する電解液注入方法において、脱気工程で、電槽の開口の上方に隙間をあけて液吸収手段を配置して脱気ボックスを上下二室に分けた状態で液吸収手段より上方の上部脱気室から脱気を行い、液吸収手段より下方の下部脱気室から大気を導入するものである。
【００１０】
こうすると、電槽の開口を大きくかつ脱気工程で所定の真空圧に達するまでの減圧時間を短縮して生産性の向上を図った場合に、極板群内に含有していた空気が吹き上げ、その気流によって電解液が飛散しようとしても、電槽の開口近傍で液吸収手段に吸収される。また、大気開放時には下部脱気室から大気が導入されるため、液吸収手段に付着していた電解液が落下して電槽の開口に付着せず、その開口を溶着等によって封止する際に悪影響を与えず、信頼性の高い密閉が実現することができる。かくして、電解液を生産性良くかつ他に弊害を生じることなく注入することができる。
【００１１】
また、注液工程を、脱気工程を間に挟んで第１注液工程と第２注液工程に分け、第１注液工程では極板群の上端より上方に液面が位置するように最終注入量よりも少ない所定量を注入し、第２注液工程で最終注入量に対する残量を注入すると、１回目の注入時に極板群が完全に液没するように電解液を注入することにより極板群に均一に電解液を含浸させることができる。
【００１２】
また、脱気工程を、第１と第２の注液工程間の第１脱気工程と、第２注液工程後の第２脱気工程と、その後の第３脱気工程に分け、第１、第２、第３の脱気工程の順に順次脱気時の真空圧を高くし、かつ第３の脱気工程は複数回繰り返すと、各注入工程後の脱気工程において真空圧を順次高くすることで極板群内のエアを効率的にかつ確実に電解液と置換でき、さらにその後に複数回更に高い真空圧の減圧と加圧を繰り返すことにより、極板群全体に均一に電解液を含浸させることができる。
【００１３】
また、本発明の電解液注入装置は、正極板と負極板をセパレータを介して積層もしくは巻回して成る極板群が収容されている電槽に電解液を注入する注液手段と、電槽を密閉状態で内部に配置可能に構成されかつ減圧手段と大気開放手段とを有する脱気ボックスとを備えた電解液注入装置において、脱気ボックスに、内部に配置された電槽の開口上方に所定の隙間をあけて対向位置するように電解液を吸収する液吸収手段を配設して脱気ボックスを上部脱気室と下部脱気室に分け、上部脱気室に減圧手段が接続され、下部脱気室に大気開放手段が接続されたものであり、上記注入方法を実施してその効果を奏することができる。
【００１４】
【発明の実施の形態】
以下、本発明の電解液注入方法及び装置の一実施形態について、図１〜図４を参照して説明する。
【００１５】
図１において、１は角形密閉式電池の角形電槽であり、図３に示すように、複数（図示例では６個）の直方体状の電槽２がその短側壁を共用して連接して構成され、各電槽２内には多数枚の正極板と多数枚の負極板とを交互に配置すると共に、正極板と負極板の間にセパレータを介装した状態で積層してなる極板群３が収容されている。各電槽２内の極板群３は角形電槽１内で順次直列接続されるとともに、その両端が角形電槽１の両端に配設された正極と負極の接続端子４に接続されている。この角形電槽１が複数（図示例では１２個）設置台５上に並列配置された状態で各工程間を移動する。
【００１６】
６は第１注液工程で電解液を注入する注液手段で、図１（ａ）及び図３に示すように、各角形電槽１の各電槽２に対応して注液ノズル６ａを備えている。７は第２注液工程で電解液を注入する注液手段で、図１（ｃ）に示すように、各角形電槽１の各電槽２に対応して注液ノズル７ａを備えている。
【００１７】
８は第１の脱気工程で角形電槽１を配置した密閉空間を形成してその内部の減圧と大気導入を行うための脱気ボックスで、並列配置された角形電槽１を上方から覆うとともに、その下端面と設置台５の上面との間でシール材９にて密閉するように構成されている。この脱気ボックス８には、内部に配置された角形電槽１の各電槽２の上面開口上方に所定の隙間ｄをあけて対向位置するように液吸収マット１０が配設された状態で上部脱気室１９と下部脱気室２０に分けられている。この液吸収マット１０より上方の上部脱気室１９に、図４に示すように、真空ポンプ１１に接続された排気口１２と開閉弁１３が配設され、液吸収マット１０より下方の下部脱気室２０に大気導入口１４と開閉弁１５が配設されている。排気口１２や大気導入口１４は適当に分散させて複数配設されており、これによって脱気ボックス８内の各電槽２に減圧による真空圧が均等に作用し、また大気導入によって均等に加圧されるように構成されている。
【００１８】
また、液吸収マット１０は不織布等にて構成され、液吸収能力が低下すると交換できるように交換自在に支持ネット等に取付けられている。この液吸収マット１０と電槽２の上面開口との隙間ｄは、液飛散を防止するという観点からはできるだけ小さくするのが好ましいが、大気導入時に各電槽２に速やかにかつ均等に大気圧を作用させるのに必要な程度の大きさは必要であり、実際には数ｍｍ〜１０ｍｍ、好適には４〜６ｍｍ程度が好ましい。
【００１９】
１６、１７は第２脱気工程と第３脱気工程における脱気ボックスで、第１脱気工程の脱気ボックス８と同様の構成である。
【００２０】
次に、以上の構成において、角形電槽１の各電槽２に所定量の電解液を注入する工程を、図１及び図２を参照して説明する。まず、ステップ＃１の第１注液工程で、図１（ａ）及び図３に示すように、注液手段６にて各電槽２内に電解液１８を定量注入する。この第１注液工程における注入量は、図３に示すように各電槽２内の極板群３の上端が完全に液没するだけの液量に設定され、これによって極板群３に均一に電解液を含浸させることができる。注入量の具体数値としては、最終注入量の約７０％程度である。
【００２１】
次に、ステップ＃２の第１脱気工程で、図１（ｂ）及び図４に示すように、脱気ボックス８にて角形電槽１を収容する密閉空間を形成した後、真空ポンプ１１を作動させ、上部脱気室１９に設けられた排気口１２に連結した開閉弁１３を開いて脱気ボックス８内を５３ｋＰａ程度の真空圧まで減圧した後、真空ポンプ１１を停止して開閉弁１３を閉じ、４０秒程度その真空圧力に保持し、その後下部脱気室２０に設けられた大気導入口１４に連結した開閉弁１５を開いて大気導入口１４から大気圧力を導入する。これによって、極板群３内に含有されていたエアと注入された電解液１８が置換され、極板群３に電解液１８が含浸される。
【００２２】
この工程で、脱気ボックス８内の真空圧力を急激に高くした場合でも、液吸収マット１０の上側に設けられた排気口１２から脱気されるため、脱気ボックス１６内の位置によらず、各電槽２において比較的均一に脱気が進行する。このため、極板群３からエアが勢い良く吹き出し、それに伴って電解液１８が撥ね飛ばされて電槽２の上面開口から飛び出すことが抑えられる。例え少量飛散したとしても、その電解液１８は液吸収マット１０に吸収されるので、電解液１８が周囲に飛散することはない。また、大気圧の導入は液吸収マット１０の下側に設けられた大気導入口１４から導入されるため、液吸収マット１０に吸収されていた電解液が下方に移動して電槽２の開口に付着することがない。
【００２３】
次に、ステップ＃３の第２注液工程で、図１（ｃ）に示すように、注液手段７にて各電槽２内に所定注入量に対して残りの量の電解液１８を定量注入する。注入量の具体数値としては、最終注入量の約３０％程度である。
【００２４】
次に、ステップ＃４の第２脱気工程で、図１（ｄ）に示すように、第一脱気工程時と同じように脱気ボックス１６にて角形電槽１を収容する密閉空間を形成した後、真空ポンプ１１を作動させ、開閉弁１３を開いて脱気ボックス１６内を第１脱気工程より高い真空圧力の８８ｋＰａ程度の真空圧まで減圧した後、真空ポンプ１１を停止して開閉弁１３を閉じ、６０秒程度その真空圧に保持し、その後開閉弁１５を開いて大気導入口１４から大気圧力を導入する。これによって、極板群３内に残っていたエアと注入された電解液１８が置換され、極板群３に電解液１８が含浸される。
【００２５】
更に、ステップ＃５の第３脱気工程で、図１（ｅ）に示すように、第一脱気工程時と同じように脱気ボックス１７にて角形電槽１を収容する密閉空間を形成した後、真空ポンプ１１を作動させ、開閉弁１３を開いて脱気ボックス１６内をさらに高い真空圧力の９６ｋＰａ程度の真空圧まで減圧した後、真空ポンプ１１を停止して開閉弁１３を閉じ、２０秒程度その真空圧に保持し、その後開閉弁１５を開いて大気導入口１４から大気圧力を導入するという動作を３回繰り返す。これによって、極板群３内に残っていたエアが完全に排除されて極板群３の全体に均一に電解液１８が含浸される。
【００２６】
本実施形態によれば、電解液注入を２回に分けているので効率的に注入できるとともに、１回目の注入時に極板群３が完全に液没するように電解液を注入しているので、極板群３に均一に電解液を含浸させることができる。
【００２７】
また、第１、第２、第３の脱気工程の順に順次脱気時の真空圧を高くし、かつ第３の脱気工程は複数回繰り返しているので、各注入工程後の脱気工程において真空圧を順次高くすることで極板群３内のエアを効率的にかつ確実に電解液１８と置換でき、さらにその後に複数回更に高い真空圧の減圧と加圧を繰り返すことにより、極板群３の全体に均一に電解液を含浸させることができる。
【００２８】
また、本実施形態では、複数の電槽２を有する角形電槽１を複数並列配置した状態で、各電槽２に対する電解液の注入を一度に行うことができるので、高い生産性を確保することができる。なお、本発明を適用できる電槽はこのような形態に限定されるものではなく、任意の形態の電槽に対する電解液注入に適用することができる。
【００２９】
なお、上記実施形態では、多数枚の正極板と多数枚の負極板とを交互に配置するとともに、正極板と負極板の間にセパレータを介装した状態で積層して極板群を構成した例を示したが、帯状の正極板と帯状の負極板と帯状のセパレータとが巻回されることによって極板群を構成してもよい。
【００３０】
【発明の効果】
本発明の電解液注入方法及び装置によれば、以上のように脱気工程で、電槽の開口の上方に隙間をあけて液吸収手段を配置した状態で液吸収手段より上方側から脱気を行い、液吸収手段より下方側から大気を導入するようにしたので、電槽の開口を大きくかつ脱気工程で所定の真空圧力に達するまでの減圧時間を短縮して、その結果極板群内に含有していた空気が勢い良く吹き上げ、その気流によって電解液が飛散しようとしても、電槽の開口近傍で液吸収手段に吸収されるので、電解液が電槽の開口に付着せず、その開口を溶着等によって封止する際に悪影響を与えないため、信頼性の高い密閉が実現することができ、したがって電解液注入を生産性良くかつ他に弊害を生じることなく行うことができる。
【００３１】
また、注液工程を、脱気工程を間に挟んで第１注液工程と第２注液工程に分け、第１注液工程では極板群の上端より上方に液面が位置するように最終注入量よりも少ない所定量を注入し、第２注液工程で最終注入量に対する残量を注入すると、電解液注入を２回に分けることで効率的に注入できるとともに、１回目の注入時に極板群が完全に液没するように電解液を注入することにより極板群に均一に電解液を含浸させることができる。
【００３２】
また、脱気工程を、第１と第２の注液工程間の第１脱気工程と、第２注液工程後の第２脱気工程と、その後の第３脱気工程に分け、第１、第２、第３の脱気工程の順に順次脱気時の真空圧を高くし、かつ第３の脱気工程は複数回繰り返すと、各注入工程後の脱気工程において真空圧を順次高くすることで極板群内のエアを効率的にかつ確実に電解液と置換でき、さらにその後に複数回更に高い真空圧の減圧と加圧を繰り返すことにより、極板群全体に均一に電解液を含浸させることができる。
【図面の簡単な説明】
【図１】本発明の一実施形態の電解液注入方法における各工程の説明図である。
【図２】同実施形態の電解液注入方法のフローチャートである。
【図３】同実施形態における電解液の注液工程を示す縦断面図である。
【図４】同実施形態における脱気工程を示す縦断面図である。
【符号の説明】
１角形電槽
２電槽
３極板群
６注液手段
７注液手段
８脱気ボックス
１０液吸収マット（液吸収手段）
１１真空ポンプ
１２排気口
１４大気導入口
１６脱気ボックス
１７脱気ボックス
１８電解液
１９上部脱気室
２０下部脱気室[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for injecting an electrolyte into a battery.
[0002]
[Prior art]
In a battery in which an electrode plate group and an electrolyte solution are formed by stacking a positive electrode plate and a negative electrode plate via a separator, such as a nickel-hydrogen battery, a lithium ion battery, or a lead storage battery, the electrolyte solution is used as the battery case. When injecting, it is necessary to fully impregnate the entire electrode plate group, particularly its separator, with the electrolyte solution. However, since the electrode plate group has a laminated structure, the electrolyte solution is simply injected into the battery case. However, the electrolytic solution cannot be uniformly impregnated as a whole at a speed at which desired productivity can be obtained.
[0003]
Therefore, conventionally, as disclosed in, for example, Japanese Patent Application Laid-Open No. 9-283114 and Japanese Patent Application Laid-Open No. 11-339770, an injection process for injecting an electrolytic solution into a battery case and a predetermined vacuum pressure are achieved. Thus, an injection method has been proposed in which the pressure is reduced and impregnated with the electrolytic solution, and then the deaeration step in which the electrolytic solution is pressurized and further impregnated by returning to the atmosphere is appropriately combined.
[0004]
In Japanese Patent Application Laid-Open No. 9-283114, a step of supplying an electrolytic solution into a container, a degassing step of sucking and removing the gas contained in the container by making the inside of the container a reduced pressure atmosphere, and pressurizing to absorb and absorb the electrolytic solution An injection method comprising the steps is disclosed.
[0005]
Japanese Patent Application Laid-Open No. 11-339770 discloses a method in which a step of impregnating an electrolytic solution under reduced pressure is repeated a plurality of times after a liquid injection step, and a vacuum pressure is increased in a subsequent pressure reduction treatment step.
[0006]
[Problems to be solved by the invention]
By the way, in order to perform the injection of the electrolytic solution with the above-described conventional injection method with high productivity, the opening of the battery case is enlarged so that the injection and deaeration can be performed quickly, and the pressure is reduced until the predetermined vacuum pressure is reached. It is effective to shorten the time of the deaeration process by shortening the time. However, if the opening of the battery case is enlarged and the decompression time is shortened, the air contained in the electrode plate group blows up vigorously during the deaeration process, and the electrolyte previously injected is scattered around by the air flow. There is a risk that.
[0007]
If the electrolyte scatters, there is a problem that the amount of electrolyte to be strictly controlled varies greatly because it greatly affects the battery performance, and the electrolyte adheres to the opening of the battery case, and the opening is welded. When sealing, there is a problem that a bad influence is given and it is difficult to perform highly reliable sealing.
[0008]
In view of the above-mentioned conventional problems, the present invention provides an electrolytic solution injection method and apparatus capable of injecting an electrolytic solution with good productivity and without causing other harmful effects into a battery case in which an electrode plate group is accommodated. The purpose is to provide.
[0009]
[Means for Solving the Problems]
The method for injecting an electrolyte according to the present invention is performed by injecting an electrolyte into a battery case in which an electrode plate group formed by laminating or winding a positive electrode plate and a negative electrode plate via a separator is accommodated. In an electrolyte injection method having a liquid injection process for injecting into a battery and a deaeration process for disposing the battery case in a deaeration box and releasing the air, the deaeration process is performed above the opening of the battery case. The liquid absorbing means is arranged with a gap and the deaeration box is divided into two upper and lower chambers, and then degassing is performed from the upper deaeration chamber above the liquid absorbing means, and from the lower degassing chamber below the liquid absorbing means. It introduces the atmosphere.
[0010]
In this way, the air contained in the electrode plate group is blown up when the opening of the battery case is enlarged and the pressure reduction time until the predetermined vacuum pressure is reached in the deaeration process is shortened to improve productivity. Even if the electrolyte is scattered by the airflow, it is absorbed by the liquid absorbing means in the vicinity of the opening of the battery case. In addition, since the atmosphere is introduced from the lower deaeration chamber when the atmosphere is released, the electrolytic solution adhering to the liquid absorbing means falls and does not adhere to the opening of the battery case, and the opening is sealed by welding or the like. A highly reliable sealing can be realized without adversely affecting the operation. Thus, the electrolytic solution can be injected with high productivity and without causing any other harmful effects.
[0011]
Also, the liquid injection process is divided into a first liquid injection process and a second liquid injection process with a deaeration process in between, so that the liquid surface is positioned above the upper end of the electrode plate group in the first liquid injection process. injecting a predetermined amount less than the final injection amount, when injecting the remaining amount to the final injection amount in the second liquid pouring step, the electrode plate group is injecting an electrolyte solution so as to completely submerged liquid upon the first infusion Thus, the electrode group can be uniformly impregnated with the electrolytic solution.
[0012]
The degassing step is divided into a first degassing step between the first and second liquid injection steps, a second degassing step after the second liquid injection step, and a third degassing step thereafter. If the vacuum pressure at the time of deaeration is sequentially increased in the order of the first, second, and third deaeration steps, and the third deaeration step is repeated a plurality of times, the vacuum pressures are sequentially increased in the deaeration step after each injection step. The air in the electrode plate group can be efficiently and reliably replaced with the electrolyte by increasing the value, and then the vacuum plate is repeatedly reduced and pressurized several times to perform uniform electrolysis on the entire electrode plate group. The liquid can be impregnated.
[0013]
Further, the electrolytic solution injection device of the present invention includes a liquid injection means for injecting an electrolytic solution into a battery case in which an electrode plate group formed by laminating or winding a positive electrode plate and a negative electrode plate with a separator interposed therebetween, and a battery case In an electrolytic solution injection apparatus comprising a deaeration box having a decompression means and an atmosphere release means, the electrolyte solution injection apparatus having a depressurization means and an air release means inside the sealing tank, and above the opening of the battery case disposed inside A liquid absorbing means for absorbing the electrolyte is arranged so as to be opposed to each other with a predetermined gap, and the deaeration box is divided into an upper deaeration chamber and a lower deaeration chamber, and a decompression means is connected to the upper deaeration chamber. An atmosphere release means is connected to the lower deaeration chamber , and the above injection method can be implemented to achieve the effect.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of an electrolytic solution injection method and apparatus according to the present invention will be described with reference to FIGS.
[0015]
In FIG. 1, reference numeral 1 denotes a rectangular battery case of a rectangular sealed battery. As shown in FIG. 3, a plurality of (six in the illustrated example) rectangular parallelepiped battery cases 2 share a short side wall and are connected. A plurality of positive electrode plates and a plurality of negative electrode plates are alternately arranged in each battery case 2, and the electrode plate group 3 is formed by laminating a separator between the positive electrode plate and the negative electrode plate. Is housed. The electrode plate group 3 in each battery case 2 is sequentially connected in series in the rectangular battery case 1, and both ends thereof are connected to positive and negative connection terminals 4 disposed at both ends of the square battery case 1. . A plurality (12 in the illustrated example) of the rectangular battery case 1 moves between the respective steps in a state of being arranged in parallel on the installation base 5.
[0016]
Reference numeral 6 denotes a liquid injection means for injecting an electrolytic solution in the first liquid injection process. As shown in FIGS. 1A and 3, a liquid injection nozzle 6 a is provided corresponding to each battery case 2 of each square battery case 1. I have. Reference numeral 7 denotes a liquid injection means for injecting an electrolytic solution in the second liquid injection step, and includes a liquid injection nozzle 7a corresponding to each battery case 2 of each rectangular battery case 1 as shown in FIG. .
[0017]
Reference numeral 8 denotes a deaeration box for forming a sealed space in which the rectangular battery case 1 is arranged in the first degassing step and performing decompression and introduction of air into the inside, and covers the parallel arranged square battery case 1 from above. And it is comprised so that it may seal with the sealing material 9 between the lower end surface and the upper surface of the installation stand 5. FIG. In this deaeration box 8, a liquid absorption mat 10 is disposed so as to be opposed to each other with a predetermined gap d above the upper surface opening of each battery case 2 of the rectangular battery case 1 disposed inside. It is divided into an upper deaeration chamber 19 and a lower deaeration chamber 20. As shown in FIG. 4, an exhaust port 12 and an on-off valve 13 connected to the vacuum pump 11 are disposed in the upper deaeration chamber 19 above the liquid absorption mat 10. An air introduction port 14 and an opening / closing valve 15 are disposed in the air chamber 20. A plurality of the exhaust ports 12 and the air introduction ports 14 are arranged in an appropriately dispersed manner, whereby the vacuum pressure due to the reduced pressure acts uniformly on each battery tank 2 in the deaeration box 8, and evenly by the introduction of the air. It is comprised so that it may be pressurized.
[0018]
Moreover, the liquid absorption mat 10 is comprised with the nonwoven fabric etc., and is attached to the support net | network etc. so that replacement | exchange is possible so that it can replace | exchange when a liquid absorption capability falls. The gap d between the liquid absorption mat 10 and the upper surface opening of the battery case 2 is preferably as small as possible from the viewpoint of preventing liquid scattering, but the atmospheric pressure is promptly and evenly applied to each battery case 2 when the atmosphere is introduced. The size required to act is necessary, and is actually several mm to 10 mm, preferably about 4 to 6 mm.
[0019]
Reference numerals 16 and 17 denote deaeration boxes in the second deaeration step and the third deaeration step, which have the same configuration as the deaeration box 8 in the first deaeration step.
[0020]
Next, a process of injecting a predetermined amount of electrolyte into each battery case 2 of the square battery case 1 in the above configuration will be described with reference to FIGS. First, in the first injection process of Step # 1, as shown in FIGS. 1 (a) and 3, the electrolyte solution 18 is quantitatively injected into each battery case 2 by the injection means 6. As shown in FIG. 3, the injection amount in the first liquid injection step is set to a liquid amount such that the upper end of the electrode plate group 3 in each battery case 2 is completely submerged. The electrolyte solution can be uniformly impregnated. The specific value of the injection amount is about 70% of the final injection amount.
[0021]
Next, in the first degassing step of Step # 2, as shown in FIGS. 1B and 4, after forming a sealed space for accommodating the rectangular battery case 1 in the degassing box 8, the vacuum pump 11 Is opened and the on-off valve 13 connected to the exhaust port 12 provided in the upper deaeration chamber 19 is opened to depressurize the inside of the deaeration box 8 to a vacuum pressure of about 53 kPa, then the vacuum pump 11 is stopped and the on-off valve 13 is closed and held at that vacuum pressure for about 40 seconds, and then the on-off valve 15 connected to the air inlet 14 provided in the lower deaeration chamber 20 is opened to introduce atmospheric pressure from the air inlet 14. As a result, the air contained in the electrode plate group 3 and the injected electrolyte solution 18 are replaced, and the electrode plate group 3 is impregnated with the electrolyte solution 18.
[0022]
In this step, even if the vacuum pressure in the deaeration box 8 is suddenly increased, the air is exhausted from the exhaust port 12 provided on the upper side of the liquid absorption mat 10. In each battery case 2, deaeration proceeds relatively uniformly. For this reason, air is blown out vigorously from the electrode plate group 3, and accordingly, the electrolytic solution 18 is repelled and prevented from jumping out from the upper surface opening of the battery case 2. Even if it is scattered in a small amount, the electrolytic solution 18 is absorbed by the liquid absorbent mat 10, so that the electrolytic solution 18 is not scattered around. Further, since the introduction of atmospheric pressure is introduced from the air introduction port 14 provided on the lower side of the liquid absorption mat 10, the electrolytic solution absorbed in the liquid absorption mat 10 moves downward to open the battery case 2. It will not adhere to.
[0023]
Next, in the second pouring step of Step # 3, as shown in FIG. 1C, the remaining amount of the electrolytic solution 18 is poured into each battery case 2 by the pouring means 7 with respect to a predetermined injection amount. Inject a fixed amount. The specific value of the injection amount is about 30% of the final injection amount.
[0024]
Next, in the second degassing step of Step # 4, as shown in FIG. 1 (d), the sealed space for accommodating the rectangular battery case 1 in the degassing box 16 is the same as in the first degassing step. After the formation, the vacuum pump 11 is operated, the on-off valve 13 is opened, the inside of the deaeration box 16 is reduced to a vacuum pressure of about 88 kPa, which is higher than the first deaeration step, and then the vacuum pump 11 is stopped. The on-off valve 13 is closed and held at the vacuum pressure for about 60 seconds, and then the on-off valve 15 is opened to introduce atmospheric pressure from the atmosphere introduction port 14. As a result, the air remaining in the electrode plate group 3 and the injected electrolyte solution 18 are replaced, and the electrode plate group 3 is impregnated with the electrolyte solution 18.
[0025]
Further, in the third degassing step of Step # 5, as shown in FIG. 1 (e), a sealed space for accommodating the rectangular battery case 1 is formed in the degassing box 17 as in the first degassing step. After that, the vacuum pump 11 is operated, the on-off valve 13 is opened and the inside of the deaeration box 16 is depressurized to a higher vacuum pressure of about 96 kPa, and then the vacuum pump 11 is stopped and the on-off valve 13 is closed. The operation of holding the vacuum pressure for about 20 seconds and then opening the on-off valve 15 and introducing atmospheric pressure from the atmospheric inlet 14 is repeated three times. As a result, the air remaining in the electrode plate group 3 is completely eliminated, and the entire electrode plate group 3 is uniformly impregnated with the electrolytic solution 18.
[0026]
According to this embodiment, since the electrolyte injection is divided into two times, the injection can be efficiently performed, and the electrolyte is injected so that the electrode plate group 3 is completely submerged during the first injection. The electrode group 3 can be uniformly impregnated with the electrolytic solution.
[0027]
Moreover, since the vacuum pressure at the time of deaeration is sequentially increased in the order of the first, second, and third deaeration steps and the third deaeration step is repeated a plurality of times, the deaeration step after each injection step In this case, the air in the electrode plate group 3 can be efficiently and reliably replaced with the electrolyte solution 18 by successively increasing the vacuum pressure in the electrode plate. The entire plate group 3 can be uniformly impregnated with the electrolytic solution.
[0028]
Moreover, in this embodiment, since the injection | pouring of the electrolyte solution with respect to each battery case 2 can be performed at once in the state which arranged the square battery case 1 which has several battery case 2 in parallel, high productivity is ensured. be able to. In addition, the battery case which can apply this invention is not limited to such a form, It can apply to electrolyte solution injection | pouring with respect to the battery case of arbitrary forms.
[0029]
In the embodiment described above, an example in which a large number of positive electrode plates and a large number of negative electrode plates are alternately arranged and laminated with a separator interposed between the positive electrode plate and the negative electrode plate to constitute an electrode plate group. As shown, the electrode plate group may be configured by winding a belt-like positive electrode plate, a belt-like negative electrode plate, and a belt-like separator.
[0030]
【Effect of the invention】
According to the electrolytic solution injection method and apparatus of the present invention, in the deaeration process as described above, deaeration is performed from above the liquid absorption unit in a state where the liquid absorption unit is disposed with a gap above the opening of the battery case. Since the atmosphere is introduced from the lower side than the liquid absorbing means, the opening of the battery case is enlarged and the depressurization time until the predetermined vacuum pressure is reached in the deaeration process is shortened. As a result, the electrode plate group Even if the air contained in the air blows up vigorously and the electrolyte solution is scattered by the air flow, it is absorbed by the liquid absorbing means near the opening of the battery case, so the electrolyte solution does not adhere to the opening of the battery case, Since the opening is not adversely affected when the opening is sealed by welding or the like, a highly reliable sealing can be realized, and therefore the electrolyte can be injected with high productivity and without causing any other adverse effects.
[0031]
Also, the liquid injection process is divided into a first liquid injection process and a second liquid injection process with a deaeration process in between, so that the liquid surface is positioned above the upper end of the electrode plate group in the first liquid injection process. By injecting a predetermined amount smaller than the final injection amount and injecting the remaining amount with respect to the final injection amount in the second injection step, it is possible to efficiently inject by dividing the electrolyte injection into two times, and at the time of the first injection By injecting the electrolytic solution so that the electrode plate group is completely submerged, the electrode plate group can be uniformly impregnated with the electrolyte solution.
[0032]
The degassing step is divided into a first degassing step between the first and second liquid injection steps, a second degassing step after the second liquid injection step, and a third degassing step thereafter. If the vacuum pressure at the time of deaeration is sequentially increased in the order of the first, second, and third deaeration steps, and the third deaeration step is repeated a plurality of times, the vacuum pressures are sequentially increased in the deaeration step after each injection step. The air in the electrode plate group can be efficiently and reliably replaced with the electrolyte by increasing the value, and then the vacuum plate is repeatedly reduced and pressurized several times to perform uniform electrolysis on the entire electrode plate group. The liquid can be impregnated.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of each step in an electrolytic solution injection method according to an embodiment of the present invention.
FIG. 2 is a flowchart of an electrolytic solution injection method according to the embodiment.
FIG. 3 is a longitudinal sectional view showing a step of injecting an electrolytic solution in the same embodiment.
FIG. 4 is a longitudinal sectional view showing a deaeration process in the same embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Square battery case 2 Battery case 3 Electrode board group 6 Injection means 7 Injection means 8 Deaeration box 10 Liquid absorption mat (liquid absorption means)
DESCRIPTION OF SYMBOLS 11 Vacuum pump 12 Exhaust port 14 Atmospheric inlet 16 Deaeration box 17 Deaeration box 18 Electrolyte 19 Upper deaeration chamber 20 Lower deaeration chamber

Claims

A pouring step of injecting the electrolyte into the battery case when injecting the electrolyte into the battery case containing a group of electrode plates formed by laminating or winding the positive electrode plate and the negative electrode plate with a separator interposed therebetween; In the electrolytic solution injection method having a deaeration process in which the tank is placed in a deaeration box and deaerated and then released to the atmosphere, in the deaeration process, a liquid absorbing means is arranged with a gap above the opening of the battery case The deaeration box is divided into two upper and lower chambers, and deaeration is performed from the upper deaeration chamber above the liquid absorption means, and the atmosphere is introduced from the lower deaeration chamber below the liquid absorption means. Electrolyte injection method.

The liquid injection process is divided into a first liquid injection process and a second liquid injection process with a deaeration process in between, and in the first liquid injection process, the final injection is performed so that the liquid surface is located above the upper end of the electrode plate group. 2. The electrolytic solution injection method according to claim 1, wherein a predetermined amount smaller than the amount is injected, and the remaining amount with respect to the final injection amount is injected in the second injection step.

The degassing step is divided into a first degassing step between the first and second liquid injection steps, a second degassing step after the second liquid injection step, and a third degassing step thereafter, 3. The electrolytic solution injection method according to claim 2, wherein the vacuum pressure at the time of deaeration is sequentially increased in the order of the second and third deaeration steps, and the third deaeration step is repeated a plurality of times.

A liquid injection means for injecting an electrolyte into a battery case containing a plate group formed by laminating or winding a positive electrode plate and a negative electrode plate with a separator interposed therebetween, and the battery case can be disposed inside in a sealed state. In addition, in the electrolytic solution injecting apparatus including the deaeration box having the decompression unit and the atmosphere release unit, the deaeration box is opposed to the deaeration box above the opening of the battery case disposed inside. Dissolving means for absorbing electrolyte to dispose the deaeration box into an upper deaeration chamber and a lower deaeration chamber, a decompression unit is connected to the upper deaeration chamber, and an air release unit is connected to the lower deaeration chamber Electrolyte injection device characterized by being made .