JP3695868B2 - Square alkaline storage battery - Google Patents

Square alkaline storage battery Download PDF

Info

Publication number
JP3695868B2
JP3695868B2 JP31092096A JP31092096A JP3695868B2 JP 3695868 B2 JP3695868 B2 JP 3695868B2 JP 31092096 A JP31092096 A JP 31092096A JP 31092096 A JP31092096 A JP 31092096A JP 3695868 B2 JP3695868 B2 JP 3695868B2
Authority
JP
Japan
Prior art keywords
electrode plate
positive electrode
nickel
active material
thickness
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP31092096A
Other languages
Japanese (ja)
Other versions
JPH10154526A (en
Inventor
忠司 伊勢
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sanyo Electric Co Ltd
Original Assignee
Sanyo Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sanyo Electric Co Ltd filed Critical Sanyo Electric Co Ltd
Priority to JP31092096A priority Critical patent/JP3695868B2/en
Publication of JPH10154526A publication Critical patent/JPH10154526A/en
Application granted granted Critical
Publication of JP3695868B2 publication Critical patent/JP3695868B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Description

【０００１】
【発明の属する技術分野】
本発明はニッケル−水素蓄電池、ニッケル−カドミウム蓄電池、ニッケル−亜鉛蓄電池などの角型アルカリ蓄電池に関するものである。
【０００２】
【従来の技術】
近年、円筒型のアルカリ蓄電池に代わり、電池使用機器内での体積効率を高めるために角型のアルカリ蓄電池が開発されるようになった。一般に、アルカリ蓄電池においては、負極板の充放電容量に較べて正極板の充放電容量が少なくなるようにして、充放電が正極制限となるように設計されている。この場合、正極板の充放電利用効率を高めるため、負極板が正極板を取り囲む構造が採用されている。
【０００３】
一方、角型のアルカリ蓄電池においては、正極板と負極板をセパレータを介して交互に積層する構造としている。このとき負極板が正極板を取り囲む構造とするならば、積層構造の最外側（積層構造の両端部）には負極板が配置される構造となるため、負極板は両側が正極板に対向するものと、片面のみが正極板に対向するもの（積層構造の両端部に配置されるもの、以下端部負極板という）の２種類が存在することとなる。
【０００４】
上記のような構造とした角型アルカリ蓄電池においては、端部負極板の容量は対向する正極板の容量に対して相対的に大きくなるため、充電時に電池内での電流分布が不均一になるとともに、この不均一な電流分布に起因して電池内でのガス吸収性能が悪化して、電池内圧が上昇するという問題を生じた。
【０００５】
ところで、アルカリ蓄電池内での発生ガスの吸収は以下に説明する原理に基づいて行われる。即ち、充電終期には満充電状態になった正極板より酸素ガスが発生し、電池内圧が上昇する。この酸素ガスは負極板によって吸収され、負極板での充電生成物が放電生成物に変化する。電池の内圧が上昇するに伴いガス吸収反応の速度も上昇する。電池内圧が充分上昇してガス発生反応とガス吸収反応がバランスすると、電池内は平衡ガス圧に保たれ、負極の充電はそれ以上進行しなくなる。
【０００６】
ここで、電池内での電流分布が不均一になるとガス吸収反応も不均一になるため、電池内に圧力勾配が生じて平衡ガス圧が高くなる。一方、電池内での電流分布を均一にするとガス吸収反応も均一になるため、電池内に圧力勾配が生じなくなり、平衡ガス圧が低くなってガス吸収性能が向上する。そこで、端部負極板の放電容量を両面が正極板に対向する負極板の放電容量に較べて少なくして、電池内での電流分布が均一になるようにしたものが特公平６−７７４６３号公報において提案されるようになった。
【０００７】
【発明が解決しようとする課題】
上述した特公平６−７７４６３号公報において提案された角型アルカリ蓄電池においては、電池内での電流分布を均一にするために端部負極板の放電容量を少なくしようとすると、端部負極板の厚みをその他の負極板の厚みの半分に薄くする必要がある。しかしながら、負極板を半分に薄くすることは製造条件も大きく異なることから、２種類の負極板を製造するためには、製造設備を変更しなければならなく、かつ電池製造時の作業性が煩雑になるとともに、製造コストが上昇するという問題を生じる。
【０００８】
また、角型アルカリ蓄電池において、帯状の芯体を共通にしてその左右に２個の負極板を形成し、その中央部がＵ字状に折曲される芯体露出部を備えて、Ｕ字状に折曲された２個の負極板間にセパレータを介して正極板を挟持させた複数組の間にセパレータを介して正極板を積層して極板群とする製法の角型アルカリ蓄電池が知られているが、この方法により角型アルカリ蓄電池を製造する場合、帯状の芯体を共通にしてその左右に厚みの異なる２個の負極板を形成することは極めて困難であるため、この方法を採用して角型アルカリ蓄電池を製造することが不可能になるという問題も生じる。
【０００９】
本発明の目的は、上記の問題に対処するため、電池の製造が容易であるとともに容積当たりの放電容量が大きく、かつガス吸収性能に優れた角型アルカリ蓄電池を得ることにある。
【００１２】
【課題を解決するための手段およびその作用・効果】
上記の目的を達成するため、本発明は、正極板と負極板とをセパレータを介して交互に積層して極板群とし、この極板群の両端部に負極板を配置して角型の金属外装缶に挿入してなる角型アルカリ蓄電池であって、前記両端部に配置される負極板に対向する正極板の放電容量を他の正極板の放電容量の１３０〜１６０％としたことを特徴とする角型アルカリ蓄電池を提供するものである。この角型アルカリ蓄電池においては、上記のように放電容量の比率を規制することにより、極板群の両端部に配置される負極板に対向する正極板の放電容量が、相対的に放電容量が大きくなる極板群の両端部に配置される負極板の放電容量と最適な比率となるため、電池内での電流分布が一層均一になって、ガス吸収反応も一層均一になり、電池内に圧力勾配が生じないために平衡ガス圧が一層低下してガス吸収性能も格段に向上する。また、両端部に配置される負極板に対向する正極板の放電容量が両端部に配置される負極板の放電容量と最適な比率になるため、高率放電や低温放電時に、両端部に配置される負極板が未放電状態で放電終了となることがなくなり、電池の容積当たりの放電容量が一層増大する。
【００１３】
本発明の一実施形態においては、 正極板と負極板とをセパレータを介して交互に積層して極板群とし、この極板群の両端部に負極板を配置して角型の金属外装缶に挿入してなる角型アルカリ蓄電池であって、前記両端部に配置される負極板に対向する正極板の厚みを他の正極板の厚みと同等にするとともに、前記両端部に配置される負極板に対向する正極板の活物質密度を他の正極板の活物質密度の１３０〜１６０％として、前記両端部に配置される負極板に対向する正極板の放電容量を他の正極板の放電容量の１３０〜１６０％としたことを特徴とする角型アルカリ蓄電池が提供される。
【００１４】
この実施形態においては、極板群の両端部に配置される負極板に対向する正極板の厚みと他の正極板の厚みとを同等にして、極板群の両端部に配置される負極板に対向する正極板の活物質密度を他の正極板の活物質密度の１３０〜１６０％とすることにより、極板群の両端部に配置される負極板に対向する正極板の活物質の充填量は他の正極板の充填量の１３０〜１６０％となるため、その放電容量が１３０〜１６０％の正極板が得られる。
【００１５】
本発明の他に実施形態においては、 正極板と負極板とをセパレータを介して交互に積層して極板群とし、この極板群の両端部に負極板を配置して角型の金属外装缶に挿入してなる角型アルカリ蓄電池であって、 前記両端部に配置される負極板に対向する正極板の活物質密度を他の正極板の活物質密度と同等にするとともに、前記両端部に配置される負極板に対向する正極板の厚みを他の正極板の厚みの１３０〜１６０％として、前記両端部に配置される負極板に対向する正極板の放電容量を他の正極板の放電容量の１３０〜１６０％としたことを特徴とする角型アルカリ蓄電池が提供される。
【００１６】
この実施形態においては、極板群の両端部に配置される負極板に対向する正極板の活物質密度と他の正極板の活物質密度とを同等にして、極板群の両端部に配置される負極板に対向する正極板の厚みを他の正極板の厚みの１３０〜１６０％としても、極板群の両端部に配置される負極板に対向する正極板の活物質の充填量は他の正極板の充填量の１３０〜１６０％となるため、その放電容量が１３０〜１６０％の正極板が得られる。この場合、極板群全体の厚みを小さくすることが可能となるため、全体的な充填量を増加させることが可能となり、一層放電容量を増加させることができる。
【００１９】
【発明の実施の形態】
以下、本発明をニッケル−水素蓄電池に適用した場合の本発明の一実施形態を図に基づいて説明する。なお、図１は極板群の両端部に配置される水素吸蔵合金負極板に対向するニッケル正極板以外の導電タブ１１ａを備えたニッケル正極板（以下、中間のニッケル正極板という）１１を示し、図２は極板群の両端部に配置される水素吸蔵合金負極板に対向する導電タブ１２ａを備えたニッケル正極板１２（以下、端部のニッケル正極板という）を示し、図３は２個の水素吸蔵合金負極板１３，１３を示し、図４はこれらのニッケル正極板１１，１２と水素吸蔵合金負極板１３，１３とをセパレータ１４を介して組み立てた極板群１０を示し、図５はこの極板群１０を収容する有底四角柱状（角型）の金属外装缶２０を示す。
【００２０】
Ａ．ニッケル正極板の作製
実施例１
ａ．中間のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを１．０８ｇ充填する。活物質スラリーを充填した極板を乾燥した後、厚みが０．４ｍｍになるように圧延して実施例１の中間のニッケル正極板１１とする。
なお、水酸化ニッケルを主成分とする活物質スラリーとしては、例えば、共沈成分として亜鉛２．５重量％とコバルト１重量％を含有する水酸化ニッケル粉末１０重量部と、酸化亜鉛粉末３重量部との混合粉末に、ヒドロキシプロピルセルロースの０．２重量％水溶液を加えて撹拌、混合したものを使用する。以下、同様に、水酸化ニッケルを主成分とする活物質スラリーはこのものを使用する。
【００２１】
ｂ．端部のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを上記中間のニッケル正極板１１の充填量の１３０％（１．４１ｇ）を充填する。活物質スラリーを中間のニッケル正極板１１の充填量の１３０％を充填した極板を乾燥した後、厚みが０．４ｍｍになるように圧延して実施例１の端部のニッケル正極板１２とする。このようにして作製した実施例１の端部のニッケル正極板１２は、中間のニッケル正極板１１と厚みが等しく（０．４ｍｍ）てその放電容量は中間のニッケル正極板１１の１３０％となる。
【００２２】
実施例２
ａ．中間のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを所定量、例えば１．０３ｇ充填する。物質スラリーを充填した極板を乾燥した後、厚みが０．４ｍｍになるように圧延して実施例２の中間のニッケル正極板１１とする。
【００２３】
ｂ．端部のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを実施例２の中間のニッケル正極板１１の充填量の１４０％（１．４４ｇ）を充填する。活物質スラリーを中間のニッケル正極板１１の充填量の１４０％を充填した極板を乾燥した後、厚みが０．４ｍｍになるように圧延して実施例２の端部のニッケル正極板１２とする。このようにして作製した実施例２の端部のニッケル正極板１２は、中間のニッケル正極板１１と厚みが等しく（０．４ｍｍ）てその放電容量は中間のニッケル正極板１１の１４０％となる。
【００２４】
実施例３
ａ．中間のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを０．９３ｇ充填する。活物質スラリーを充填した極板を乾燥した後、厚みが０．４ｍｍになるように圧延して実施例３の中間のニッケル正極板１１とする。
【００２５】
ｂ．端部のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを上記中間のニッケル正極板１１の充填量の１６０％（１．４９ｇ）を充填する。活物質スラリーを中間のニッケル正極板１１の充填量の１６０％を充填した極板を乾燥した後、厚みが０．４ｍｍになるように圧延して実施例３の端部のニッケル正極板１２とする。このようにして作製した実施例３の端部のニッケル正極板１２は、中間のニッケル正極板１１と厚みが等しく（０．４ｍｍ）てその放電容量は中間のニッケル正極板１１の１６０％となる。
【００２６】
実施例４
ａ．中間のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを１．０８ｇ充填する。活物質スラリーを充填した極板を乾燥した後、厚みが０．３３ｍｍになるように圧延して実施例４の中間のニッケル正極板１１とする。このように製作した実施例４の中間のニッケル正極板１１の活物質充填密度は４．５ｇ／ｃｍ3となる。
【００２７】
ｂ．端部のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを実施例４の中間のニッケル正極板１１の充填量の１３０％（１．４１ｇ）を充填する。活物質スラリーを中間のニッケル正極板１１の充填量の１３０％を充填した極板を乾燥した後、厚みが０．４３ｍｍになるように圧延して実施例４の端部のニッケル正極板１２とする。このようにして作製した実施例４の端部のニッケル正極板１２の活物質充填密度は４．５ｇ／ｃｍ3となる。したがって、実施例４の端部のニッケル正極板１２は、中間のニッケル正極板１１と充填密度が等しく（４．５ｇ／ｃｍ3）てその放電容量は中間のニッケル正極板１１の１３０％となる。
【００２８】
実施例５
ａ．中間のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを１．０３ｇ充填する。活物質スラリーを充填した極板を乾燥した後、厚みが０．３２ｍｍになるように圧延して実施例５の中間のニッケル正極板１１とする。このように製作した実施例５の中間のニッケル正極板１１の活物質充填密度は４．５ｇ／ｃｍ3となる。
【００２９】
ｂ．端部のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを実施例５の中間のニッケル正極板１１の充填量の１４０％（１．４４ｇ）を充填する。活物質スラリーを中間のニッケル正極板１１の充填量の１４０％を充填した極板を乾燥した後、厚みが０．４４ｍｍになるように圧延して実施例５の端部のニッケル正極板１２とする。このようにして作製した実施例５の端部のニッケル正極板１２の活物質充填密度は４．５ｇ／ｃｍ3となる。したがって、実施例５の端部のニッケル正極板１２は、中間のニッケル正極板１１と充填密度が等しく（４．５ｇ／ｃｍ3）てその放電容量は中間のニッケル正極板１１の１４０％となる。
【００３０】
実施例６
ａ．中間のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを０．９３ｇ充填する。活物質スラリーを充填した極板を乾燥した後、厚みが０．２９ｍｍになるように圧延して実施例６の中間のニッケル正極板１１とする。このように製作した実施例６の中間のニッケル正極板１１の活物質充填密度は４．５ｇ／ｃｍ3となる。
【００３１】
ｂ．端部のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを実施例６の中間のニッケル正極板１１の充填量の１６０％（１．４９ｇ）を充填する。活物質スラリーを中間のニッケル正極板１１の充填量の１６０％を充填した極板を乾燥した後、厚みが０．４６ｍｍになるように圧延して実施例６の端部のニッケル正極板１２とする。このようにして作製した実施例６の端部のニッケル正極板１２の活物質充填密度は４．５ｇ／ｃｍ3となる。したがって、実施例６の端部のニッケル正極板１２は、中間のニッケル正極板１１と充填密度が等しく（４．５ｇ／ｃｍ3）てその放電容量は中間のニッケル正極板１１の１６０％となる。
【００３２】
比較例１
ａ．中間のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを１．３０ｇ充填する。活物質スラリーを充填した極板を乾燥した後、厚みが０．４ｍｍになるように圧延して比較例１の中間のニッケル正極板１１とする。
【００３３】
ｂ．端部のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを比較例１の中間のニッケル正極板１１の充填量の１００％（約１．３０ｇ）を充填する。活物質スラリーを中間のニッケル正極板１１の充填量の１００％を充填した極板を乾燥した後、厚みが０．４０ｍｍになるように圧延して比較例１の端部のニッケル正極板１２とする。このようにして作製した比較例１の端部のニッケル正極板１２は、中間のニッケル正極板１１と厚みが等しく（０．４０ｍｍ）てその放電容量も中間のニッケル正極板１１の１００％となる。
【００３４】
比較例２
ａ．中間のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを１．１５ｇ充填する。活物質スラリーを充填した極板を乾燥した後、厚みが０．４０ｍｍになるように圧延して比較例２の中間のニッケル正極板１１とする。
【００３５】
ｂ．端部のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを比較例２の中間のニッケル正極板１１の充填量の１２０％（１．３８ｇ）を充填する。活物質スラリーを中間のニッケル正極板１１の充填量の１２０％を充填した極板を乾燥した後、厚みが０．４０ｍｍになるように圧延して比較例２の端部のニッケル正極板１２とする。このようにして作製した比較例２の端部のニッケル正極板１２は、中間のニッケル正極板１１と厚みが等しく（０．４０ｍｍ）てその放電容量は中間のニッケル正極板１１の１２０％となる。
【００３６】
比較例３
ａ．中間のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを０．８９ｇ充填する。活物質スラリーを充填した極板を乾燥した後、厚みが０．４０ｍｍになるように圧延して中間のニッケル正極板１１とする。
【００３７】
ｂ．端部のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを比較例３の中間のニッケル正極板１１の充填量の１７０％（１．５１ｇ）を充填する。活物質スラリーを中間のニッケル正極板１１の充填量の１７０％を充填した極板を乾燥した後、厚みが０．４０ｍｍになるように圧延して比較例３の端部のニッケル正極板１２とする。このようにして作製した比較例３の端部のニッケル正極板１２は、中間のニッケル正極板１１と厚みが等しく（０．４０ｍｍ）てその放電容量は中間のニッケル正極板１１の１７０％となる。
【００３８】
比較例４
ａ．中間のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを所定量、例えば１．１５ｇ充填する。活物質スラリーを充填した極板を乾燥した後、厚みが０．３５ｍｍになるように圧延して中間のニッケル正極板１１とする。このように製作した比較例４の中間のニッケル正極板１１の活物質充填密度は４．５ｇ／ｃｍ3となる。
【００３９】
ｂ．端部のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを比較例４の中間のニッケル正極板１１の充填量の１２０％（１．３８ｇ）を充填する。活物質スラリーを中間のニッケル正極板１１の充填量の１２０％を充填した極板を乾燥した後、厚みが０．４２ｍｍになるように圧延して比較例４の端部のニッケル正極板１２とする。このようにして作製した比較例４の端部のニッケル正極板１２の活物質充填密度は４．５ｇ／ｃｍ3となる。したがって、比較例４の端部のニッケル正極板１２は、中間のニッケル正極板１１と充填密度が等しく（４．５ｇ／ｃｍ3）てその放電容量は中間のニッケル正極板１１の１２０％となる。
【００４０】
比較例５
ａ．中間のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを０．８９ｇ充填する。活物質スラリーを充填した極板を乾燥した後、厚みが０．２７ｍｍになるように圧延して比較例５の中間のニッケル正極板１１とする。このように製作した比較例５の中間のニッケル正極板１１の活物質充填密度は４．５ｇ／ｃｍ3となる。
【００４１】
ｂ．端部のニッケル正極板の作製
発泡ニッケル等よりなる三次元的に連続する空間を有する厚みが１．０ｍｍの金属多孔体よりなる芯体に水酸化ニッケルを主成分とする活物質スラリーを比較例５の中間のニッケル正極板１１の充填量の１７０％（１．５１ｇ）を充填する。活物質スラリーを中間のニッケル正極板１１の充填量の１７０％を充填した極板を乾燥した後、厚みが０．４６ｍｍになるように圧延して比較例５の端部のニッケル正極板１２とする。このようにして作製した比較例５の端部のニッケル正極板１２の活物質充填密度は４．５ｇ／ｃｍ3となる。したがって、比較例５の端部のニッケル正極板１２は、中間のニッケル正極板１１と充填密度が等しく（４．５ｇ／ｃｍ3）てその放電容量は中間のニッケル正極板１１の１７０％となる。
【００４２】
Ｂ．水素吸蔵合金負極板の作製
Ｔｉ−Ｎｉ系あるいはＬａ（もしくはＭｍ）−Ｎｉ系の多元合金、例えば、ＭｍＮｉ3.4Ｃｏ0.8Ａｌ0.2Ｍｎ0.6合金よりなる水素吸蔵合金粉末に結着剤としてポテトラフルオロエチレン（ＰＴＦＥ）粉末を水素吸蔵合金粉末に対して５重量％加えて混練し、負極活物質ペーストとする。この負極活物質ペーストを、パンチングメタル等からなる帯状金属芯体３ａにその中央部が露出するように左右両側に塗着した後、両面から加圧して中央部で接続された２個の電極板からなる水素吸蔵合金負極板１３，１３を作製する。
【００４３】
Ｃ．角型ニッケル−水素蓄電池の作製
上記ように作製した２個の電極板からなる水素吸蔵合金負極板１３，１３を２枚用意し、この水素吸蔵合金負極板１３，１３の中央部をＵ字状に折曲して、セパレータ１４を介して端部のニッケル正極板１２を挟持させ、この端部のニッケル正極板１２が挟持された水素吸蔵合金負極板１３，１３の２組の間に、セパレータ１４を介して中間のニッケル正極板１１を積層して１１種類の極板群１０とする。その後、中間のニッケル正極板１１の導電タブ１１ａと各端部のニッケル正極板１２，１２の導電タブ１２ａ，１２ａとをそれぞれ溶接する。これらの導電タブ１１ａ，１２ａ，１２ａは外部端子２１に電気的に接続される。
【００４４】
このように形成した１１種類の極板群１０をそれぞれ１１個の有底四角柱状（角型）の金属外装缶２０に挿入し、端部負極板１３，１３と金属外装缶２０の内側面とを緊密に接触させるとともに、帯状金属芯体１３ａの露出した中央部が金属外装缶２０の内底面とを緊密に接触させる。この１１個の金属外装缶２０にそれぞれ３０重量％の水酸化カリウム（ＫＯＨ）水溶液よりなる電解液を注液することにより、１１種類の角型ニッケル−水素蓄電池を作製する。
【００４５】
Ｄ．電池特性試験
上記したように作製した１１種類の各角型ニッケル−水素蓄電池を６０ｍＡの充電々流で１６時間充電した後、１時間休止させる。その後、１４０ｍＡの放電々流で終止電圧が１．０Ｖになるまで放電させた後、１時間休止させる。この充放電を室温で３サイクル繰り返して、各角型ニッケル−水素蓄電池を活性化する。
【００４６】
ついで、このようにして充放電を室温で３サイクル繰り返した放電状態の１１種類の角型ニッケル−水素蓄電池を６０ｍＡの充電々流で１．５時間充電を行ったときの電池内圧を測定すると、下記表１に示すような実験結果が得られた。
【００４７】
【表１】

Figure 0003695868
【００４８】
この表１の実験結果より、以下のことが明らかとなった。即ち、実施例１〜実施例３のように、中間のニッケル正極板１１と厚みを等しくしてその活物質の充填密度を変化させて、端部のニッケル正極板１２，１２の放電容量を中間のニッケル正極板１１の放電容量の１３０〜１６０％としても、実施例４〜実施例６のように中間のニッケル正極板１１と活物質の充填密度を等しくしてその厚みを変化させて、端部のニッケル正極板１２，１２の放電容量を中間のニッケル正極板１１の放電容量の１３０〜１６０％としても、比較例１〜比較例５の角型ニッケル−水素蓄電池のいずれよりも電池内圧が低下した。
【００４９】
この理由は次のように考えることができる。即ち、端部のニッケル正極板１２，１２の放電容量を中間のニッケル正極板１１の放電容量の１３０〜１６０％とすると、端部のニッケル正極板１２，１２の放電容量が、相対的に放電容量が大きくなる両端部に配置される水素吸蔵合金負極板１３，１３の放電容量と最適な比率となるため、電池内での電流分布が均一になる。電池内での電流分布が均一になると、水素吸蔵合金負極板１３，１３のガス吸収反応も均一になり、電池内に圧力勾配が生じないために平衡ガス圧が低下してガス吸収性能も格段に向上するためと考えられる。
【００５０】
そして、端部のニッケル正極板１２，１２の放電容量が両端部に配置される水素吸蔵合金負極板１３，１３の放電容量と最適な比率になると、両端部に配置される水素吸蔵合金負極板１３，１３が未放電状態で放電終了となることがなくなるため、高率放電や低温放電時の電池全体としての放電効率が上昇して、電池の容積当たりの放電容量が一層増大する。
【００５１】
なお、実施例４〜実施例６のように中間のニッケル正極板１１と活物質の充填密度を等しくしてその厚みを変化させて、端部のニッケル正極板１２，１２の放電容量を中間のニッケル正極板１１の放電容量の１３０〜１６０％とすると、極板群１０全体の厚みを小さくすることが可能となるため、全体的な充填量を増加させることが可能となり、一層放電容量を増加させることができる。
【００５２】
また、Ｕ字状に折曲された２個の水素吸蔵合金負極板１３，１３間にセパレータ１４を介して端部のニッケル正極板１２を挟持させるようにすると、極板群１０を金属外装缶２０内に挿入する際に端部負極板１３，１３が位置ずれを起こすことがなくなるので、電池組立の作業性が向上する。また、両端部に配置される負極板１３，１３を金属外装缶２０の内側面に圧接させるとともに芯体露出部１３ａを金属外装缶２０の内底面に圧接させているので、極板群１０にガタつきが生じることを防止できるようになり、かつ溶接工程を削減できるので組立不良の発生を防止できるようになる。
【図面の簡単な説明】
【図１】 中間のニッケル正極板（その他の正極板）を示す図である。
【図２】 端部のニッケル正極板（両端部に配置される負極板に対向する正極板）を示す図である。
【図３】 ２個の水素吸蔵合金負極板を示す図である。
【図４】 極板群を示す図である。
【図５】 角型金属外装缶を示す図である。
【符号の説明】
１０…極板群、１１…中間のニッケル正極板（その他の正極板）、１１ａ…導電タブ、１２…端部のニッケル正極板（両端部に配置される負極板に対向する正極板）、１２ａ…導電タブ、１３…水素吸蔵合金負極板、１４…セパレータ、２０…角型金属外装缶、２１…外部端子[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a prismatic alkaline storage battery such as a nickel-hydrogen storage battery, a nickel-cadmium storage battery, or a nickel-zinc storage battery.
[0002]
[Prior art]
In recent years, instead of cylindrical alkaline storage batteries, rectangular alkaline storage batteries have been developed in order to increase volumetric efficiency in battery-operated equipment. In general, the alkaline storage battery is designed such that the charge / discharge is limited by the positive electrode so that the charge / discharge capacity of the positive electrode plate is smaller than the charge / discharge capacity of the negative electrode plate. In this case, a structure in which the negative electrode plate surrounds the positive electrode plate is employed in order to increase the charge / discharge utilization efficiency of the positive electrode plate.
[0003]
On the other hand, the prismatic alkaline storage battery has a structure in which positive plates and negative plates are alternately stacked via separators. If the negative electrode plate surrounds the positive electrode plate at this time, the negative electrode plate is arranged on the outermost side of the laminated structure (both ends of the laminated structure), and therefore the negative electrode plate faces both sides of the positive electrode plate. There are two types: one that faces the positive electrode plate only on one side (one that is disposed at both ends of the laminated structure, hereinafter referred to as end negative electrode plate).
[0004]
In the prismatic alkaline storage battery having the above-described structure, the capacity of the end negative plate is relatively large with respect to the capacity of the opposing positive plate, so that the current distribution in the battery becomes non-uniform during charging. At the same time, due to this non-uniform current distribution, the gas absorption performance in the battery deteriorates and the internal pressure of the battery increases.
[0005]
By the way, absorption of the generated gas in the alkaline storage battery is performed based on the principle described below. That is, at the end of charging, oxygen gas is generated from the fully charged positive electrode plate, and the battery internal pressure rises. This oxygen gas is absorbed by the negative electrode plate, and the charge product at the negative electrode plate changes to a discharge product. As the internal pressure of the battery increases, the rate of gas absorption reaction also increases. When the internal pressure of the battery rises sufficiently to balance the gas generation reaction and the gas absorption reaction, the inside of the battery is maintained at an equilibrium gas pressure, and the charging of the negative electrode does not proceed any further.
[0006]
Here, when the current distribution in the battery becomes non-uniform, the gas absorption reaction also becomes non-uniform, so that a pressure gradient is generated in the battery and the equilibrium gas pressure becomes high. On the other hand, when the current distribution in the battery is made uniform, the gas absorption reaction also becomes uniform, so that no pressure gradient is generated in the battery, the equilibrium gas pressure is lowered, and the gas absorption performance is improved. Therefore, Japanese Patent Publication No. 6-77463 has a structure in which the discharge capacity of the end negative plate is made smaller than the discharge capacity of the negative plate opposite to the positive plate so that the current distribution in the battery is uniform. Proposed in the gazette.
[0007]
[Problems to be solved by the invention]
In the prismatic alkaline storage battery proposed in the above-mentioned Japanese Patent Publication No. 6-77463, if the discharge capacity of the end negative plate is reduced in order to make the current distribution in the battery uniform, It is necessary to reduce the thickness to half the thickness of the other negative electrode plate. However, thinning the negative electrode plate in half greatly varies the manufacturing conditions. Therefore, in order to manufacture two types of negative electrode plates, the manufacturing equipment must be changed, and the workability during battery manufacturing is complicated. As a result, there arises a problem that the manufacturing cost increases.
[0008]
Further, in the rectangular alkaline storage battery, a strip-shaped core body is shared, two negative plates are formed on the left and right sides thereof, and a core body exposed portion whose central portion is bent into a U-shape is provided. A prismatic alkaline storage battery of the manufacturing method in which a positive electrode plate is laminated via a separator between a plurality of sets in which the positive electrode plate is sandwiched between two negative electrode plates bent in a shape to form an electrode plate group. Although it is known, when manufacturing a square alkaline storage battery by this method, it is extremely difficult to form two negative plates with different thicknesses on the left and right sides using a common belt-shaped core. There is also a problem that it becomes impossible to manufacture a prismatic alkaline storage battery by employing the above.
[0009]
  The purpose of the present invention is to address the above problems.An object of the present invention is to obtain a prismatic alkaline storage battery that is easy to manufacture and has a large discharge capacity per volume and excellent gas absorption performance.
[0012]
[Means for solving the problems and their functions and effects]
  In order to achieve the above-mentioned object, the present invention is to form a plate group by alternately laminating positive plates and negative plates via separators, and disposing a negative plate at both ends of the plate group to form a square shape. It is a prismatic alkaline storage battery inserted into a metal outer can, and the discharge capacity of the positive electrode plate facing the negative electrode plate disposed at both ends is 130 to 160% of the discharge capacity of the other positive electrode plate. A rectangular alkaline storage battery is provided. In this rectangular alkaline storage battery, as described aboveBy regulating the ratio of the discharge capacity, the discharge capacity of the positive electrode plate facing the negative electrode plate arranged at both ends of the electrode plate group is arranged at both ends of the electrode plate group having a relatively large discharge capacity. Since the discharge capacity of the negative electrode plate is an optimum ratio, the current distribution in the battery becomes more uniform, the gas absorption reaction becomes more uniform, and the pressure gradient does not occur in the battery. The gas absorption performance will be greatly improved by lowering. Also, since the discharge capacity of the positive electrode plate facing the negative electrode plate placed at both ends is the optimal ratio with the discharge capacity of the negative electrode plate placed at both ends, it is placed at both ends during high rate discharge or low temperature discharge. When the negative electrode plate is not discharged, the discharge is not terminated, and the discharge capacity per battery volume is further increased.
[0013]
    In one embodiment of the present invention, a positive electrode plate and a negative electrode plate are alternately stacked via a separator to form an electrode plate group, and the negative electrode plate is disposed at both ends of the electrode plate group to form a rectangular metal outer can. A positive electrode plate opposite to the negative electrode plates disposed at both ends, and having the same thickness as the other positive electrode plates, and the negative electrodes disposed at both ends The active material density of the positive electrode plate facing the plate is 130 to 160% of the active material density of the other positive electrode plate, and the discharge capacity of the positive electrode plate facing the negative electrode plate disposed at both ends is the discharge of the other positive electrode plate. A prismatic alkaline storage battery characterized by having a capacity of 130 to 160% is provided.
[0014]
  In this embodiment,The thickness of the positive electrode plate opposed to the negative electrode plate arranged at both ends of the electrode plate group is equal to the thickness of the other positive electrode plate, and the positive electrode plate opposed to the negative electrode plate arranged at both ends of the electrode plate group By setting the active material density to 130 to 160% of the active material density of the other positive electrode plate, the active material filling amount of the positive electrode plate facing the negative electrode plate disposed at both ends of the electrode plate group is different from the other positive electrode plate. Therefore, a positive electrode plate having a discharge capacity of 130 to 160% is obtained.
[0015]
  In another embodiment of the present invention, a positive electrode plate and a negative electrode plate are alternately laminated via a separator to form an electrode plate group, and the negative electrode plate is disposed at both ends of the electrode plate group to form a square metal sheath. A prismatic alkaline storage battery inserted into a can, The active material density of the positive electrode plate facing the negative electrode plate arranged at both end portions is made equal to the active material density of the other positive electrode plate, and the thickness of the positive electrode plate facing the negative electrode plate arranged at the both end portions is The thickness of the other positive electrode plate is 130 to 160%, and the discharge capacity of the positive electrode plate facing the negative electrode plate disposed at both ends is 130 to 160% of the discharge capacity of the other positive electrode plate. A prismatic alkaline storage battery is provided.
[0016]
  In this embodiment,The active material density of the positive electrode plate facing the negative electrode plate arranged at both ends of the electrode plate group is made equal to the active material density of the other positive electrode plate, and the negative electrode plate arranged at both ends of the electrode plate group is opposed. Even if the thickness of the positive electrode plate is 130 to 160% of the thickness of the other positive electrode plate, the active material filling amount of the positive electrode plate facing the negative electrode plate disposed at both ends of the electrode plate group is the filling amount of the other positive electrode plate. Therefore, a positive electrode plate with a discharge capacity of 130 to 160% is obtained. In this case, since the thickness of the entire electrode plate group can be reduced, the overall filling amount can be increased, and the discharge capacity can be further increased.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, one embodiment of the present invention when the present invention is applied to a nickel-hydrogen storage battery will be described with reference to the drawings. FIG. 1 shows a nickel positive electrode plate (hereinafter referred to as an intermediate nickel positive electrode plate) 11 having a conductive tab 11a other than a nickel positive electrode plate facing the hydrogen storage alloy negative electrode plates disposed at both ends of the electrode plate group. FIG. 2 shows a nickel positive electrode plate 12 (hereinafter referred to as an end nickel positive electrode plate) having conductive tabs 12a facing the hydrogen storage alloy negative electrode plates disposed at both ends of the electrode plate group. FIG. 4 shows an electrode plate group 10 in which these nickel positive electrode plates 11 and 12 and hydrogen storage alloy negative electrode plates 13 and 13 are assembled via a separator 14. Reference numeral 5 denotes a bottomed quadrangular prismatic (square) metal outer can 20 that accommodates the electrode plate group 10.
[0020]
A. Production of nickel positive electrode plate
Example 1
a. Preparation of intermediate nickel positive plate
1.08 g of an active material slurry containing nickel hydroxide as a main component is filled in a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. After drying the electrode plate filled with the active material slurry, it is rolled to a thickness of 0.4 mm to obtain an intermediate nickel positive electrode plate 11 of Example 1.
The active material slurry containing nickel hydroxide as a main component includes, for example, 10 parts by weight of nickel hydroxide powder containing 2.5% by weight of zinc and 1% by weight of cobalt as a coprecipitation component, and 3% by weight of zinc oxide powder. A 0.2% by weight aqueous solution of hydroxypropylcellulose is added to the mixed powder with a part and stirred and mixed. Hereinafter, similarly, this is used as an active material slurry mainly composed of nickel hydroxide.
[0021]
b. Fabrication of the end nickel plate
Filling amount of the intermediate nickel positive electrode plate 11 with an active material slurry having nickel hydroxide as a main component in a core made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. Of 130% (1.41 g). After drying the electrode plate filled with 130% of the filling amount of the intermediate nickel positive electrode plate 11 with the active material slurry, it was rolled to a thickness of 0.4 mm, and the nickel positive electrode plate 12 at the end of Example 1 and To do. The nickel positive electrode plate 12 at the end of Example 1 manufactured in this way has the same thickness (0.4 mm) as the intermediate nickel positive electrode plate 11 and its discharge capacity is 130% of that of the intermediate nickel positive electrode plate 11. .
[0022]
Example 2
a. Preparation of intermediate nickel positive plate
A predetermined amount, for example, 1.03 g of an active material slurry containing nickel hydroxide as a main component is filled in a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. After drying the electrode plate filled with the material slurry, it is rolled to a thickness of 0.4 mm to obtain an intermediate nickel positive electrode plate 11 of Example 2.
[0023]
b. Fabrication of the end nickel plate
An active material slurry mainly composed of nickel hydroxide is applied to a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. 140% (1.44 g) of the filling amount is filled. After drying the electrode plate filled with 140% of the filling amount of the intermediate nickel positive electrode plate 11 with the active material slurry, it was rolled to a thickness of 0.4 mm, and the nickel positive electrode plate 12 at the end of Example 2 and To do. The nickel positive electrode plate 12 at the end of Example 2 manufactured in this way has the same thickness (0.4 mm) as the intermediate nickel positive electrode plate 11 and its discharge capacity is 140% of that of the intermediate nickel positive electrode plate 11. .
[0024]
Example 3
a. Preparation of intermediate nickel positive plate
0.93 g of an active material slurry containing nickel hydroxide as a main component is filled in a core made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. After drying the electrode plate filled with the active material slurry, it is rolled to a thickness of 0.4 mm to obtain an intermediate nickel positive electrode plate 11 of Example 3.
[0025]
b. Fabrication of the end nickel plate
Filling amount of the intermediate nickel positive electrode plate 11 with an active material slurry having nickel hydroxide as a main component in a core made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. Of 160% (1.49 g). After drying the electrode plate in which 160% of the filling amount of the intermediate nickel positive electrode plate 11 was filled with the active material slurry, the electrode plate was rolled to a thickness of 0.4 mm, and the nickel positive electrode plate 12 at the end of Example 3 and To do. The nickel positive electrode plate 12 at the end of Example 3 manufactured in this way has the same thickness (0.4 mm) as the intermediate nickel positive electrode plate 11, and its discharge capacity is 160% of that of the intermediate nickel positive electrode plate 11. .
[0026]
Example 4
a. Preparation of intermediate nickel positive plate
1.08 g of an active material slurry containing nickel hydroxide as a main component is filled in a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. After drying the electrode plate filled with the active material slurry, it is rolled to a thickness of 0.33 mm to obtain an intermediate nickel positive electrode plate 11 of Example 4. The active material packing density of the intermediate nickel positive electrode plate 11 of Example 4 manufactured in this way is 4.5 g / cm.ThreeIt becomes.
[0027]
b. Fabrication of the end nickel plate
An active material slurry mainly composed of nickel hydroxide is applied to a core body made of a porous metal body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. 130% (1.41 g) of the filling amount is filled. After drying the electrode plate filled with 130% of the filling amount of the intermediate nickel positive electrode plate 11 with the active material slurry, it was rolled to a thickness of 0.43 mm, and the nickel positive electrode plate 12 at the end of Example 4 and To do. The active material packing density of the nickel positive electrode plate 12 at the end of Example 4 manufactured in this way was 4.5 g / cm.ThreeIt becomes. Therefore, the nickel positive electrode plate 12 at the end of Example 4 has the same packing density as the intermediate nickel positive electrode plate 11 (4.5 g / cmThreeThe discharge capacity is 130% of the intermediate nickel positive electrode plate 11.
[0028]
Example 5
a. Preparation of intermediate nickel positive plate
1.03 g of an active material slurry containing nickel hydroxide as a main component is filled in a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. After the electrode plate filled with the active material slurry is dried, it is rolled to a thickness of 0.32 mm to obtain an intermediate nickel positive electrode plate 11 of Example 5. The active material packing density of the intermediate nickel positive electrode plate 11 of Example 5 manufactured in this way is 4.5 g / cm.ThreeIt becomes.
[0029]
b. Fabrication of the end nickel plate
An active material slurry mainly composed of nickel hydroxide is applied to a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. 140% (1.44 g) of the filling amount is filled. After drying the electrode plate filled with 140% of the filling amount of the intermediate nickel positive electrode plate 11 with the active material slurry, the electrode plate is rolled to a thickness of 0.44 mm, and the nickel positive electrode plate 12 at the end of Example 5 To do. The active material packing density of the nickel positive electrode plate 12 at the end of Example 5 manufactured in this manner was 4.5 g / cm.ThreeIt becomes. Therefore, the nickel positive electrode plate 12 at the end of Example 5 has the same packing density as the intermediate nickel positive electrode plate 11 (4.5 g / cmThreeThe discharge capacity is 140% of that of the intermediate nickel positive electrode plate 11.
[0030]
Example 6
a. Preparation of intermediate nickel positive plate
0.93 g of an active material slurry containing nickel hydroxide as a main component is filled in a core made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. After the electrode plate filled with the active material slurry is dried, it is rolled to a thickness of 0.29 mm to obtain an intermediate nickel positive electrode plate 11 of Example 6. The active material packing density of the intermediate nickel positive electrode plate 11 of Example 6 manufactured in this way was 4.5 g / cm.ThreeIt becomes.
[0031]
b. Fabrication of the end nickel plate
An active material slurry mainly composed of nickel hydroxide is applied to a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. 160% (1.49 g) of the filling amount of After drying the electrode plate filled with 160% of the filling amount of the intermediate nickel positive electrode plate 11 with the active material slurry, it was rolled to a thickness of 0.46 mm, and the end of the nickel positive electrode plate 12 of Example 6 and To do. The active material packing density of the nickel positive electrode plate 12 at the end of Example 6 produced in this manner was 4.5 g / cm.ThreeIt becomes. Therefore, the nickel positive electrode plate 12 at the end of Example 6 has the same packing density as the intermediate nickel positive electrode plate 11 (4.5 g / cmThreeThe discharge capacity is 160% of that of the intermediate nickel positive electrode plate 11.
[0032]
Comparative Example 1
a. Preparation of intermediate nickel positive plate
1.30 g of an active material slurry containing nickel hydroxide as a main component is filled in a core made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. After drying the electrode plate filled with the active material slurry, the electrode plate is rolled to a thickness of 0.4 mm to obtain an intermediate nickel positive electrode plate 11 of Comparative Example 1.
[0033]
b. Fabrication of the end nickel plate
An active material slurry mainly composed of nickel hydroxide is applied to a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. 100% (about 1.30 g) of the filling amount of After drying the electrode plate in which 100% of the filling amount of the intermediate nickel positive electrode plate 11 is filled with the active material slurry, the electrode plate is rolled to a thickness of 0.40 mm, and the nickel positive electrode plate 12 at the end of Comparative Example 1 is used. To do. The nickel positive electrode plate 12 at the end of Comparative Example 1 manufactured in this way has the same thickness (0.40 mm) as the intermediate nickel positive electrode plate 11 and its discharge capacity is 100% of that of the intermediate nickel positive electrode plate 11. .
[0034]
Comparative Example 2
a. Preparation of intermediate nickel positive plate
1.15 g of an active material slurry mainly composed of nickel hydroxide is filled in a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. After drying the electrode plate filled with the active material slurry, the electrode plate is rolled to a thickness of 0.40 mm to obtain an intermediate nickel positive electrode plate 11 of Comparative Example 2.
[0035]
b. Fabrication of the end nickel plate
The nickel positive electrode plate 11 in the middle of the comparative example 2 is made of an active material slurry mainly composed of nickel hydroxide on a core made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. 120% (1.38 g) of the filling amount of After drying the electrode plate in which 120% of the filling amount of the intermediate nickel positive electrode plate 11 was filled with the active material slurry, the electrode plate was rolled to a thickness of 0.40 mm, and the nickel positive electrode plate 12 at the end of Comparative Example 2 was To do. The nickel positive electrode plate 12 at the end of Comparative Example 2 manufactured in this way has the same thickness (0.40 mm) as the intermediate nickel positive electrode plate 11, and its discharge capacity is 120% of that of the intermediate nickel positive electrode plate 11. .
[0036]
Comparative Example 3
a. Preparation of intermediate nickel positive plate
0.89 g of an active material slurry containing nickel hydroxide as a main component is filled in a core made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. After drying the electrode plate filled with the active material slurry, it is rolled to a thickness of 0.40 mm to obtain an intermediate nickel positive electrode plate 11.
[0037]
b. Fabrication of the end nickel plate
An active material slurry containing nickel hydroxide as a main component on a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like is an intermediate nickel positive electrode plate 11 of Comparative Example 3. 170% (1.51 g) of the filling amount is filled. After drying the electrode plate in which 170% of the filling amount of the intermediate nickel positive electrode plate 11 was filled with the active material slurry, the electrode plate was rolled to a thickness of 0.40 mm, and the nickel positive electrode plate 12 at the end of Comparative Example 3 was To do. The nickel positive electrode plate 12 at the end of Comparative Example 3 manufactured in this way has the same thickness (0.40 mm) as the intermediate nickel positive electrode plate 11 and its discharge capacity is 170% of that of the intermediate nickel positive electrode plate 11. .
[0038]
Comparative Example 4
a. Preparation of intermediate nickel positive plate
A predetermined amount, for example, 1.15 g, of an active material slurry mainly composed of nickel hydroxide is filled in a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. After the electrode plate filled with the active material slurry is dried, it is rolled to a thickness of 0.35 mm to obtain an intermediate nickel positive electrode plate 11. The active material filling density of the intermediate nickel positive electrode plate 11 of Comparative Example 4 manufactured in this way is 4.5 g / cm.ThreeIt becomes.
[0039]
b. Fabrication of the end nickel plate
The nickel positive electrode plate 11 in the middle of the comparative example 4 is made of an active material slurry mainly composed of nickel hydroxide on a core made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. 120% (1.38 g) of the filling amount of After drying the electrode plate in which 120% of the filling amount of the intermediate nickel positive electrode plate 11 was filled with the active material slurry, the electrode plate was rolled to a thickness of 0.42 mm and the end of the nickel positive electrode plate 12 of Comparative Example 4 To do. The active material packing density of the nickel positive electrode plate 12 at the end of Comparative Example 4 thus produced was 4.5 g / cm.ThreeIt becomes. Therefore, the nickel positive electrode plate 12 at the end of the comparative example 4 has the same packing density as the intermediate nickel positive electrode plate 11 (4.5 g / cmThreeThe discharge capacity is 120% of that of the intermediate nickel positive electrode plate 11.
[0040]
Comparative Example 5
a. Preparation of intermediate nickel positive plate
0.89 g of an active material slurry containing nickel hydroxide as a main component is filled in a core made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. After drying the electrode plate filled with the active material slurry, it is rolled to a thickness of 0.27 mm to obtain an intermediate nickel positive electrode plate 11 of Comparative Example 5. The active material filling density of the intermediate nickel positive electrode plate 11 of Comparative Example 5 manufactured in this way is 4.5 g / cm.ThreeIt becomes.
[0041]
b. Fabrication of the end nickel plate
An active material slurry mainly composed of nickel hydroxide is applied to a core body made of a metal porous body having a thickness of 1.0 mm and having a three-dimensionally continuous space made of foamed nickel or the like. 170% (1.51 g) of the filling amount is filled. After drying the electrode plate filled with 170% of the filling amount of the intermediate nickel positive electrode plate 11 with the active material slurry, it was rolled to a thickness of 0.46 mm, and the nickel positive electrode plate 12 at the end of Comparative Example 5 and To do. The active material packing density of the nickel positive electrode plate 12 at the end of Comparative Example 5 thus produced was 4.5 g / cm.ThreeIt becomes. Therefore, the nickel positive electrode plate 12 at the end of the comparative example 5 has the same packing density as the intermediate nickel positive electrode plate 11 (4.5 g / cmThreeThe discharge capacity is 170% of that of the intermediate nickel positive electrode plate 11.
[0042]
B. Preparation of hydrogen storage alloy negative electrode plate
Ti-Ni-based or La (or Mm) -Ni-based multi-component alloys such as MmNi3.4Co0.8Al0.2Mn0.6Potassium fluoroethylene (PTFE) powder as a binder is added to a hydrogen storage alloy powder made of an alloy at 5% by weight with respect to the hydrogen storage alloy powder and kneaded to obtain a negative electrode active material paste. After coating this negative electrode active material paste on a band-shaped metal core 3a made of punching metal or the like on both the left and right sides so that the central part is exposed, the two electrode plates are pressed from both sides and connected at the central part The hydrogen storage alloy negative electrode plates 13 and 13 are prepared.
[0043]
C. Fabrication of prismatic nickel-hydrogen storage battery
Two hydrogen storage alloy negative electrode plates 13, 13 made of the two electrode plates prepared as described above were prepared, and the central portions of the hydrogen storage alloy negative electrode plates 13, 13 were bent into a U-shape to form a separator 14. An intermediate nickel positive electrode plate 12 is sandwiched between two pairs of hydrogen storage alloy negative electrode plates 13 and 13 sandwiching the nickel positive electrode plate 12 at the end. The plates 11 are stacked to form eleven types of electrode plate groups 10. Thereafter, the conductive tab 11a of the intermediate nickel positive electrode plate 11 and the conductive tabs 12a and 12a of the nickel positive electrode plates 12 and 12 at the ends are respectively welded. These conductive tabs 11 a, 12 a and 12 a are electrically connected to the external terminal 21.
[0044]
The eleven types of electrode plate groups 10 formed in this way are inserted into eleven bottomed square columnar (square) metal outer cans 20, respectively, and the negative electrode plates 13, 13 and the inner surface of the metal outer can 20 are Are in close contact with each other, and the exposed central portion of the strip-shaped metal core 13a is in close contact with the inner bottom surface of the metal outer can 20. Eleven types of prismatic nickel-hydrogen storage batteries are manufactured by injecting an electrolytic solution made of a 30 wt% potassium hydroxide (KOH) aqueous solution into each of the 11 metal outer cans 20.
[0045]
D. Battery characteristics test
Each of the 11 types of prismatic nickel-hydrogen storage batteries prepared as described above is charged for 16 hours at a charging current of 60 mA, and then rested for 1 hour. Thereafter, the battery is discharged at a discharge current of 140 mA until the final voltage becomes 1.0 V, and then rested for 1 hour. This charging / discharging is repeated three times at room temperature to activate each prismatic nickel-hydrogen storage battery.
[0046]
Next, when the internal pressure of the 11 kinds of prismatic nickel-hydrogen storage batteries in a discharged state in which charging / discharging was repeated three times at room temperature in this way was charged for 1.5 hours at a charging current of 60 mA, Experimental results as shown in Table 1 below were obtained.
[0047]
[Table 1]
Figure 0003695868
[0048]
From the experimental results in Table 1, the following became clear. That is, as in the first to third embodiments, the thickness of the intermediate nickel positive electrode plate 11 is made equal and the filling density of the active material is changed, so that the discharge capacity of the nickel positive electrode plates 12 and 12 at the end is intermediate. Even if the discharge capacity of the nickel positive electrode plate 11 is 130 to 160%, the thickness of the intermediate nickel positive electrode plate 11 and the active material are made equal to each other and the thickness thereof is changed as in Examples 4 to 6, Even if the discharge capacity of the nickel positive electrode plates 12, 12 is 130 to 160% of the discharge capacity of the intermediate nickel positive electrode plate 11, the battery internal pressure is higher than any of the prismatic nickel-hydrogen storage batteries of Comparative Examples 1 to 5. Declined.
[0049]
The reason can be considered as follows. That is, when the discharge capacity of the nickel positive plates 12 and 12 at the end is 130 to 160% of the discharge capacity of the intermediate nickel positive plate 11, the discharge capacity of the nickel positive plates 12 and 12 at the end is relatively discharged. Since it becomes an optimal ratio with the discharge capacity of the hydrogen storage alloy negative electrode plates 13 and 13 arranged at both ends where the capacity increases, the current distribution in the battery becomes uniform. When the current distribution in the battery becomes uniform, the gas absorption reaction of the hydrogen storage alloy negative electrode plates 13 and 13 also becomes uniform, and no pressure gradient is generated in the battery. It is thought to improve.
[0050]
Then, when the discharge capacity of the nickel positive electrode plates 12 and 12 at the end portions becomes an optimal ratio with the discharge capacity of the hydrogen storage alloy negative electrode plates 13 and 13 disposed at both ends, the hydrogen storage alloy negative electrode plates disposed at both ends 13 and 13 do not end discharging in an undischarged state, so that the discharge efficiency of the battery as a whole during high-rate discharge or low-temperature discharge increases, and the discharge capacity per battery volume further increases.
[0051]
It should be noted that the intermediate nickel positive electrode plate 11 and the packing density of the active material are made equal to each other and the thickness thereof is changed as in Example 4 to Example 6, so that the discharge capacity of the nickel positive electrode plates 12 and 12 at the end portions is intermediate. If the discharge capacity of the nickel positive electrode plate 11 is 130 to 160%, the total thickness of the electrode plate group 10 can be reduced, so that the overall filling amount can be increased and the discharge capacity is further increased. Can be made.
[0052]
When the nickel positive electrode plate 12 at the end is sandwiched between the two hydrogen storage alloy negative electrode plates 13 and 13 bent in a U shape via the separator 14, the electrode plate group 10 is made of a metal outer can. Since the end negative plates 13 and 13 are not displaced when they are inserted into the battery 20, the workability of the battery assembly is improved. Moreover, since the negative electrode plates 13 and 13 disposed at both ends are pressed against the inner side surface of the metal outer can 20 and the core exposed portion 13a is pressed against the inner bottom surface of the metal outer can 20, It becomes possible to prevent the rattling from occurring, and the welding process can be reduced, so that the assembly failure can be prevented.
[Brief description of the drawings]
FIG. 1 is a view showing an intermediate nickel positive electrode plate (another positive electrode plate).
FIG. 2 is a view showing an end nickel positive plate (a positive plate facing a negative plate disposed at both ends).
FIG. 3 is a view showing two hydrogen storage alloy negative electrode plates.
FIG. 4 is a diagram showing an electrode plate group.
FIG. 5 is a view showing a rectangular metal outer can.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Electrode plate group, 11 ... Intermediate | middle nickel positive electrode plate (other positive electrode plates), 11a ... Conductive tab, 12 ... End nickel positive electrode plate (positive electrode plate facing the negative electrode plate arrange | positioned at both ends), 12a ... Conductive tab, 13 ... Hydrogen storage alloy negative electrode plate, 14 ... Separator, 20 ... Square metal outer can, 21 ... External terminal

Claims (3)

正極板と負極板とをセパレータを介して交互に積層して極板群とし、この極板群の両端部に負極板を配置して角型の金属外装缶に挿入してなる角型アルカリ蓄電池であって、
前記両端部に配置される負極板に対向する正極板の放電容量を他の正極板の放電容量の１３０〜１６０％としたことを特徴とする角型アルカリ蓄電池。A prismatic alkaline storage battery in which a positive electrode plate and a negative electrode plate are alternately laminated via a separator to form an electrode plate group, and the negative electrode plate is disposed at both ends of the electrode plate group and inserted into a rectangular metal outer can. Because
A prismatic alkaline storage battery characterized in that the discharge capacity of a positive electrode plate facing the negative electrode plate disposed at both ends is 130 to 160% of the discharge capacity of another positive electrode plate. 正極板と負極板とをセパレータを介して交互に積層して極板群とし、この極板群の両端部に負極板を配置して角型の金属外装缶に挿入してなる角型アルカリ蓄電池であって、
前記両端部に配置される負極板に対向する正極板の厚みを他の正極板の厚みと同等にするとともに、前記両端部に配置される負極板に対向する正極板の活物質密度を他の正極板の活物質密度の１３０〜１６０％として、前記両端部に配置される負極板に対向する正極板の放電容量を他の正極板の放電容量の１３０〜１６０％としたことを特徴とする角型アルカリ蓄電池。 A prismatic alkaline storage battery in which a positive electrode plate and a negative electrode plate are alternately laminated via a separator to form an electrode plate group, and the negative electrode plate is disposed at both ends of the electrode plate group and inserted into a rectangular metal outer can. Because
The thickness of the positive electrode plate facing the negative electrode plate arranged at both ends is made equal to the thickness of the other positive electrode plate, and the active material density of the positive electrode plate facing the negative electrode plate arranged at both ends is changed to other The active material density of the positive electrode plate is 130 to 160%, and the discharge capacity of the positive electrode plate facing the negative electrode plate disposed at both ends is 130 to 160% of the discharge capacity of the other positive electrode plate. A square alkaline storage battery. 正極板と負極板とをセパレータを介して交互に積層して極板群とし、この極板群の両端部に負極板を配置して角型の金属外装缶に挿入してなる角型アルカリ蓄電池であって、
前記両端部に配置される負極板に対向する正極板の活物質密度を他の正極板の活物質密度と同等にするとともに、前記両端部に配置される負極板に対向する正極板の厚みを他の正極板の厚みの１３０〜１６０％として、前記両端部に配置される負極板に対向する正極板の放電容量を他の正極板の放電容量の１３０〜１６０％としたことを特徴とする角型アルカリ蓄電池。 A prismatic alkaline storage battery in which a positive electrode plate and a negative electrode plate are alternately laminated via a separator to form an electrode plate group, and the negative electrode plate is disposed at both ends of the electrode plate group and inserted into a rectangular metal outer can. Because
The active material density of the positive electrode plate facing the negative electrode plate arranged at both end portions is made equal to the active material density of the other positive electrode plate, and the thickness of the positive electrode plate facing the negative electrode plate arranged at the both end portions is The thickness of the other positive electrode plate is 130 to 160%, and the discharge capacity of the positive electrode plate facing the negative electrode plate disposed at both ends is 130 to 160% of the discharge capacity of the other positive electrode plate. A square alkaline storage battery.
JP31092096A 1996-11-21 1996-11-21 Square alkaline storage battery Expired - Fee Related JP3695868B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP31092096A JP3695868B2 (en) 1996-11-21 1996-11-21 Square alkaline storage battery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP31092096A JP3695868B2 (en) 1996-11-21 1996-11-21 Square alkaline storage battery

Publications (2)

Publication Number Publication Date
JPH10154526A JPH10154526A (en) 1998-06-09
JP3695868B2 true JP3695868B2 (en) 2005-09-14

Family

ID=18010985

Family Applications (1)

Application Number Title Priority Date Filing Date
JP31092096A Expired - Fee Related JP3695868B2 (en) 1996-11-21 1996-11-21 Square alkaline storage battery

Country Status (1)

Country Link
JP (1) JP3695868B2 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6653023B1 (en) 1999-03-25 2003-11-25 Sanyo Electric Co., Ltd. Rectangular battery
JP3625731B2 (en) * 1999-03-25 2005-03-02 三洋電機株式会社 Square battery
KR101435212B1 (en) * 2008-09-17 2014-08-28 주식회사 엘지화학 Multilayered-Secondary battery including electrodes with different thickness

Also Published As

Publication number Publication date
JPH10154526A (en) 1998-06-09

Similar Documents

Publication Publication Date Title
JP3056054B2 (en) Zinc secondary battery and zinc electrode
JP3943822B2 (en) Battery spiral electrode group and battery
JP2001319682A (en) Square alkaline storage battery, and unit battery and assembled battery using the same
KR100224464B1 (en) Alkaline secondary battery manufacturing method, alkaline secondary battery positive electrode, alkaline secondary battery, and a method of manufacturing an initially charged alkaline secondary battery
JP2005011699A (en) Lithium secondary battery
JP3695868B2 (en) Square alkaline storage battery
US5773163A (en) Sealed alkaline storage battery
US6653023B1 (en) Rectangular battery
US6649303B2 (en) Alkaline storage battery with group of spiral electrodes
JP3902330B2 (en) Cylindrical battery
JPH08264174A (en) Hydrogen storage alloy cathode and its preparation
US5584892A (en) Process for producing nickel electrode having lightweight substrate
JP3625731B2 (en) Square battery
JP2989877B2 (en) Nickel hydride rechargeable battery
JP2001143712A5 (en)
JP3339327B2 (en) Storage battery
JPS58129789A (en) Flat type nickel-cadmium battery
JP2594147B2 (en) Metal-hydrogen alkaline storage battery
JP2988974B2 (en) Prismatic nickel-metal hydride storage battery
JPS63131472A (en) Metal-hydrogen alkaline storage battery
JP2558587B2 (en) Negative electrode for nickel-hydrogen secondary battery
JP4441191B2 (en) Alkaline storage battery and method for manufacturing the same
JP2771584B2 (en) Manufacturing method of non-sintering type sealed alkaline storage battery
JP4783980B2 (en) Cylindrical secondary battery
JPH11162502A (en) Manufacture of alkaline secondary battery

Legal Events

Date Code Title Description
A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20050120

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20050315

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20050516

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20050614

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20050628

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20080708

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20090708

Year of fee payment: 4

LAPS Cancellation because of no payment of annual fees