JP3469766B2 - Non-sintered nickel electrodes and batteries for sealed alkaline storage batteries - Google Patents
Non-sintered nickel electrodes and batteries for sealed alkaline storage batteriesInfo
- Publication number
- JP3469766B2 JP3469766B2 JP01940898A JP1940898A JP3469766B2 JP 3469766 B2 JP3469766 B2 JP 3469766B2 JP 01940898 A JP01940898 A JP 01940898A JP 1940898 A JP1940898 A JP 1940898A JP 3469766 B2 JP3469766 B2 JP 3469766B2
- Authority
- JP
- Japan
- Prior art keywords
- nickel
- active material
- cobalt
- oxyhydroxide
- weight
- 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 - Lifetime
Links
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
Description
【０００１】[0001]
【本発明の属する技術分野】本発明は、密閉型アルカリ
蓄電池用非焼結式ニッケル極及びそのニッケル極を用い
た電池に係わり、詳しくは放電リザーブを削減し、高容
量でしかも高率放電特性の優れた密閉型アルカリ蓄電池
用ニッケル極を提供することを目的とした、活物質の改
良に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-sintered nickel electrode for a sealed alkaline storage battery and a battery using the nickel electrode. More specifically, it has a reduced discharge reserve, a high capacity and a high rate discharge characteristic. And an improved active material for the purpose of providing a nickel electrode for a sealed alkaline storage battery.
【０００２】[0002]
【従来の技術及】従来、ニッケル−水素蓄電池、ニッケ
ル−カドミウム蓄電池等の密閉型アルカリ蓄電池の正極
として、ニッケル粉末を穿孔鋼板等に焼結させて得た焼
結基板に活物質（水酸化ニッケル）を含浸させてなる焼
結式ニッケル極がよく知られている。2. Description of the Related Art Conventionally, as a positive electrode of a sealed alkaline storage battery such as a nickel-hydrogen storage battery or a nickel-cadmium storage battery, an active material (nickel hydroxide) is applied to a sintered substrate obtained by sintering nickel powder into a perforated steel plate or the like. ) Is well known as a sintered nickel electrode.
【０００３】焼結式ニッケル極において活物質の充填量
を多くするためには、多孔度の大きい焼結基板を用いる
必要がある。しかし、焼結によるニッケル粒子間の結合
は弱いので、焼結基板の多孔度を大きくするとニッケル
粒子が焼結式基板から脱落し易くなる。従って、実用上
は、焼結基板の多孔度を80％より大きくすることができ
ない。それゆえ焼結ニッケル極には、活物質充填量が少
ないという問題がある。また、一般に、ニッケル粉末の
焼結体の孔径は10μｍ以下と小さいため、活物質の焼結
基板への充填を、煩雑な含浸工程を数回繰り返す必要が
ある溶液含浸法により行わなければならないという問題
もある。In order to increase the filling amount of the active material in the sintered nickel electrode, it is necessary to use a sintered substrate having high porosity. However, since the bonding between the nickel particles due to sintering is weak, increasing the porosity of the sintered substrate makes it easier for the nickel particles to fall off the sintered substrate. Therefore, practically, the porosity of the sintered substrate cannot be made higher than 80%. Therefore, the sintered nickel electrode has a problem that the filling amount of the active material is small. In addition, since the pore size of the sintered body of nickel powder is generally as small as 10 μm or less, it is necessary to fill the sintered substrate with the active material by the solution impregnation method which requires repeated complicated impregnation steps several times. There are also problems.
【０００４】このようなことから、最近、ペースト式ニ
ッケル極に代表される非焼結式ニッケル極が提案されて
いる。ペースト式ニッケル極は、活物質（水酸化ニッケ
ル）と結着剤（メチルセルロース水溶液など）との混練
物（ペースト）を多孔度の大きい基板に充填することに
より作製される。ペースト式ニッケル極では、多孔度の
大きい基板を用いることができるので（多孔度95％以上
の基板を用いることができる）、活物質の充填量を多く
することができるとともに、活物質の基板への充填が容
易である。Under these circumstances, recently, a non-sintered nickel electrode represented by a paste nickel electrode has been proposed. The paste-type nickel electrode is prepared by filling a kneaded material (paste) of an active material (nickel hydroxide) and a binder (aqueous solution of methylcellulose etc.) into a substrate having a high porosity. Since the paste type nickel electrode can use a substrate having a large porosity (a substrate having a porosity of 95% or more can be used), it is possible to increase the filling amount of the active material and to use the active material on the substrate. Is easy to fill.
【０００５】しかしながら、ペースト式ニッケル極にお
いて活物質の充填量を多くするべく多孔度の大きい基板
を用いると、基板の集電性が悪くなり、活物質利用率が
低下する。However, if a substrate having a high porosity is used in order to increase the filling amount of the active material in the paste type nickel electrode, the current collecting property of the substrate is deteriorated and the utilization rate of the active material is lowered.
【０００６】そこで、ペースト式ニッケル極の活物質利
用率を高めるべく、水酸化ニッケルに導電剤として水酸
化コバルト［Ｃｏ(ＯＨ）2]を添加することが提案され
ている（特開昭61-49374号公報参照）。コバルト２価の
水酸化コバルトは初回の充電によりコバルト３価のオキ
シ水酸化コバルト（β−ＣｏＯＯＨ）に酸化され、これ
が導電性ネットワークを形成して、活物質利用率を向上
させる。Therefore, it has been proposed to add cobalt hydroxide [Co (OH) 2 ] as a conductive agent to nickel hydroxide in order to increase the utilization rate of the active material of the paste-type nickel electrode (Japanese Patent Laid-Open No. 61-61). (See Japanese Patent No. 49374). The cobalt divalent cobalt hydroxide is oxidized to cobalt trivalent cobalt oxyhydroxide (β-CoOOH) by the first charge, which forms a conductive network and improves the utilization rate of the active material.
【０００７】ところで、ニッケル−水素蓄電池やニッケ
ル−カドミウム蓄電池は、負極容量を正極容量に比べて
大きくして、正極が満充電されても負極には未充電部分
（以下、この未充電部分の理論容量を「充電リザーブ」と
称する。）が存在するように設計されている。この充電
リザーブは、充電末期及び過充電時に正極から発生する
酸素ガス（２ＯＨ-→１／２Ｏ2＋Ｈ2Ｏ＋２ｅ-）を負極
で吸収させることにより（カドミウム極の場合：Ｃｄ＋
１／２Ｏ2＋Ｈ2Ｏ→Ｃｄ(ＯＨ)2；水素極の場合：２Ｍ
Ｈ＋１／２Ｏ2→２Ｍ＋Ｈ2Ｏ）、密閉型電池の内圧の上
昇を抑制するために設けられるものもあるが、特に高率
放電時の負極の活物質利用率の低下に因る放電容量の低
下を抑制する働きも有している。By the way, in the nickel-hydrogen storage battery and the nickel-cadmium storage battery, the negative electrode capacity is made larger than the positive electrode capacity so that even if the positive electrode is fully charged, the negative electrode has an uncharged portion (hereinafter, the theory of this uncharged portion is The capacity is referred to as the "charging reserve"). This charge reserve is obtained by absorbing oxygen gas (2OH − → 1 / 2O 2 + H 2 O + 2e − ) generated from the positive electrode at the end of charging and overcharging at the negative electrode (in the case of a cadmium electrode: Cd +
1 / 2O 2 + H 2 O → Cd (OH) 2 ; hydrogen electrode: 2M
(H + 1 / 2O 2 → 2M + H 2 O), some are provided to suppress the rise in internal pressure of the sealed battery, but especially the discharge capacity decreases due to the reduction of the active material utilization rate of the negative electrode during high rate discharge. It also has the function of suppressing
【０００８】上記した従来のペースト式ニッケル極にお
ける、充電時の水酸化コバルトからオキシ水酸化コバル
トへの酸化は不可逆である。即ち、充電時に生成したオ
キシ水酸化コバルトは放電時に還元されず、オキシ水酸
化コバルトのままである。従って、水酸化コバルトから
オキシ水酸化コバルトへの酸化に要した電気量は、潜在
的な放電電気量（以下、「放電リザーブ」と称する。）と
して負極に蓄えられることになる。また、充放電反応
も、完全な可逆反応ではない。即ち、充電により生成し
たオキシ水酸化ニッケルは、放電により完全に水酸化ニ
ッケルに還元されない。従って、初回の充放電において
正極活物質の酸化に要した充電電気量と還元に要した放
電電気量の差に等しい電気量が、放電リザーブとして負
極に蓄えられる。Oxidation of cobalt hydroxide to cobalt oxyhydroxide at the time of charging in the above-mentioned conventional paste type nickel electrode is irreversible. That is, the cobalt oxyhydroxide generated during charging is not reduced during discharging and remains as cobalt oxyhydroxide. Therefore, the amount of electricity required for the oxidation of cobalt hydroxide to cobalt oxyhydroxide is stored in the negative electrode as a potential amount of discharge electricity (hereinafter, referred to as “discharge reserve”). Also, the charge / discharge reaction is not a completely reversible reaction. That is, the nickel oxyhydroxide generated by charging is not completely reduced to nickel hydroxide by discharging. Therefore, an amount of electricity equal to the difference between the amount of charge electricity required for oxidation of the positive electrode active material and the amount of discharge electricity required for reduction in the first charge / discharge is stored in the negative electrode as a discharge reserve.
【０００９】電池に充填した活物質に占める放電リザー
ブの割合が大きい場合、実際に利用できる活物質の割合
が小さくなるため、電池の容量が低下するという問題が
あった。そこで、放電リザーブを削減することが、電池
の高容量化に対して有効であると考えられる。When the ratio of the discharge reserve in the active material filled in the battery is large, the ratio of the active material that can be actually used is small, which causes a problem that the capacity of the battery is reduced. Therefore, it is considered that reducing the discharge reserve is effective for increasing the capacity of the battery.
【００１０】しかし、放電リザーブには高率放電時の放
電末期に負極電位の上昇による電池電圧低下を抑制する
働きがあるので、負極容量に占める放電リザーブの割合
は、少な過ぎても高率放電での放電容量は低下する。従
って、高率放電での放電容量が大きいアルカリ蓄電池を
与える非焼結式ニッケル極を得るためには、放電リザー
ブが適正となるように、正極の不可逆反応量を設計する
必要がある。However, since the discharge reserve has the function of suppressing the battery voltage drop due to the rise of the negative electrode potential at the end of discharge at the time of high rate discharge, the ratio of the discharge reserve to the negative electrode capacity is too small even if it is high rate discharge. Discharge capacity decreases. Therefore, in order to obtain a non-sintered nickel electrode that provides an alkaline storage battery with a large discharge capacity at high rate discharge, it is necessary to design the irreversible reaction amount of the positive electrode so that the discharge reserve is appropriate.
【００１１】放電リザーブを適正にするということは、
初回の充放電における充電電気量と放電電気量の差を適
正にすることに等しい。正極導電剤として、水酸化コバ
ルトに代えて、特公平8-24041号公報で提案されている
オキシ水酸化コバルトを使用すれば、オキシ水酸化コバ
ルトは充放電により酸化も還元もされないから、正極導
電剤に起因して生成する放電リザーブを零（０）にする
ことができる。To make the discharge reserve proper means
This is equivalent to making the difference between the charged electricity amount and the discharged electricity amount in the first charge / discharge appropriate. If cobalt oxyhydroxide proposed in Japanese Examined Patent Publication No. 8-24041 is used instead of cobalt hydroxide as the positive electrode conductive agent, cobalt oxyhydroxide is neither oxidized nor reduced by charging and discharging. The discharge reserve generated due to the agent can be zero (0).
【００１２】また、特公昭60-254564号公報で提案され
ている水酸化ニッケル粉末とオキシ水酸化ニッケル粉末
及びコバルト粉末を含む活物質混合物を用いた場合、コ
バルトの酸化に要する電気量分の放電リザーブをオキシ
水酸化ニッケルを添加することにより低減することがで
きる。Further, when an active material mixture containing nickel hydroxide powder, nickel oxyhydroxide powder and cobalt powder proposed in Japanese Patent Publication No. 60-254564 is used, discharge of an amount of electricity required for oxidation of cobalt is used. The reserve can be reduced by adding nickel oxyhydroxide.
【００１３】しかしながら、負極の放電リザーブは、正
極導電剤に起因して生成する放電リザーブと正極活物質
に起因して生成する放電リザーブの合計量であるから、
正極活物質に起因して生成する放電リザーブも減少させ
なければ、放電リザーブを適正にすることはできない。However, the discharge reserve of the negative electrode is the total amount of the discharge reserve generated by the positive electrode conductive material and the discharge reserve generated by the positive electrode active material.
The discharge reserve cannot be optimized unless the discharge reserve generated due to the positive electrode active material is also reduced.
【００１４】[0014]
【発明が解決しようとする課題】従って、本発明は、高
率放電での放電容量が大きい密閉型アルカリ蓄電池を作
製することを可能とする、負極に適切な放電リザーブを
生成せしめる非焼結式ニッケル極を提供することを目的
とする。Therefore, the present invention is a non-sintering type that can produce an appropriate discharge reserve for the negative electrode, which enables the production of a sealed alkaline storage battery having a large discharge capacity at a high rate discharge. The purpose is to provide a nickel electrode.
【００１５】[0015]
【課題を解決するための手段】上記目的を達成するた
め、本発明に係る密閉型アルカリ蓄電池用非焼結式ニッ
ケル極は、水酸化ニッケルをオキシ水酸化コバルトで被
覆した第１の活物質と、オキシ水酸化ニッケルをオキシ
水酸化コバルトで被覆した第２の活物質とを９０：１０
〜６０：４０の重量比率で混合した活物質が用いられて
おり、かつ、前記第１の活物質において、オキシ水酸化
コバルトが、コバルトの原子換算での比率で水酸化ニッ
ケル粉末に対して１．０〜１０．０重量％の割合で添加
され、かつ、前記第２の活物質において、オキシ水酸化
コバルトが、コバルトの原子換算での比率でオキシ水酸
化ニッケル粉末に対して１．０〜１０．０重量％の割合
で添加されていることを特徴とする。 In order to achieve the above object, a non-sintered nickel electrode for a sealed alkaline storage battery according to the present invention comprises a first active material obtained by coating nickel hydroxide with cobalt oxyhydroxide. 90:10 with a second active material obtained by coating nickel oxyhydroxide with cobalt oxyhydroxide.
~ 60: 40 weight ratio mixed active material used
And in the first active material, oxyhydroxide
Cobalt can be converted into nickel hydroxide at the atomic conversion ratio of cobalt.
Kel powder added at a ratio of 1.0 to 10.0% by weight
And in the second active material, oxyhydroxide
Cobalt is oxyhydric acid at the ratio of cobalt atom conversion
Ratio of 1.0 to 10.0% by weight based on nickel chloride powder
Is added in.
【００１６】ここで、オキシ水酸化ニッケルから構成さ
れる第２の活物質の重量比率が10重量％未満の場合は、
充放電反応における正極の不可逆反応量が多くなり、負
極の放電リザーブが過多となる。その結果、電池に充填
した活物質のうち、実際利用できる活物質の割合が低下
するため、容量の低下が生じる。一方、オキシ水酸化ニ
ッケルから構成される第２の活物質の重量比率が40重量
％を超える場合充放電反応における可逆反応が多くな
り、放電リザーブが過少となる。その結果、放電末期及
び高率放電時の負極電位の上昇を充分に抑制することが
できなくなり、高率放電時の電池の放電容量が低下す
る。よって、第１の活物質と第２の活物質を90：10〜6
0：40の重量比率で混合使用する。Here, when the weight ratio of the second active material composed of nickel oxyhydroxide is less than 10% by weight,
The irreversible reaction amount of the positive electrode in the charge / discharge reaction increases, and the discharge reserve of the negative electrode becomes excessive. As a result, the proportion of the active material that can be actually used in the active material filled in the battery is reduced, resulting in a decrease in capacity. On the other hand, when the weight ratio of the second active material composed of nickel oxyhydroxide exceeds 40% by weight, the reversible reaction in the charge / discharge reaction increases and the discharge reserve becomes insufficient. As a result, the increase in the negative electrode potential at the end of discharge and at the time of high rate discharge cannot be suppressed sufficiently, and the discharge capacity of the battery at the time of high rate discharge is reduced. Therefore, the first active material and the second active material should be 90: 10-6.
Mix and use in a weight ratio of 0:40.
【００１７】更に、第１の活物質と第２の活物質を80：
20〜70：30の重量比率で混合使用することによって、サ
イクル特性が一層向上することが可能となる。Further, the first active material and the second active material are 80:
By mixing and using in a weight ratio of 20 to 70:30, cycle characteristics can be further improved.
【００１８】また、正極活物質としての第１の活物質及
び／若しくは第２の活物質の水酸化ニッケル及び／若し
くはオキシ水酸化ニッケルに、亜鉛、マグネシウム、カ
ルシウム、マンガン、アルミニウム、カドミウム、イッ
トリウム、コバルト、ビスマス、ランタン、イッテルビ
ウム、エルビウム、ガドリニウム及びセリウムから選ば
れた少なくとも１種の元素を固溶させてもよい。これら
の元素を固溶させることにより、正極活物質の膨化を抑
制することができる。In addition, nickel hydroxide and / or nickel oxyhydroxide as the first active material and / or the second active material as the positive electrode active material are added to zinc, magnesium, calcium, manganese, aluminum, cadmium, yttrium, At least one element selected from cobalt, bismuth, lanthanum, ytterbium, erbium, gadolinium and cerium may be solid-dissolved. Swelling of the positive electrode active material can be suppressed by forming a solid solution with these elements.
【００１９】ここで、第２の活物質に使用されるオキシ
水酸化ニッケルは、例えば、水酸化ニッケルを準備し、
過酸化水素水、次亜塩素酸塩水溶液に水酸化ナトリウム
等のアルカリを添加した水溶液に、撹拌しながら所定時
間（通常、３〜60分間）浸漬することにより容易に作製
できる。上記アルカリを添加する理由は、水溶液のｐＨ
を高めてオキシ水酸化ニッケルへの酸化を促進するため
である。Here, as the nickel oxyhydroxide used for the second active material, for example, nickel hydroxide is prepared,
It can be easily prepared by immersing in an aqueous solution of hydrogen peroxide or an aqueous solution of hypochlorite to which an alkali such as sodium hydroxide is added while stirring for a predetermined time (usually 3 to 60 minutes). The reason for adding the above alkali is the pH of the aqueous solution.
Is to promote oxidation to nickel oxyhydroxide.
【００２０】また、第１の活物質において、オキシ水酸
化コバルトは、コバルトの原子換算での比率で水酸化ニ
ッケル粉末に対して１．０〜１０．０重量％の割合で添
加され、さらに、第２の活物質において、オキシ水酸化
コバルトは、コバルトの原子換算での比率でオキシ水酸
化ニッケル粉末に対して１．０〜１０．０重量％の割合
で添加されているが、同被覆量が１．０重量％未満の場
合は活物質利用率が低下するため、また同添加量が１
０．０重量％を超えた場合はニッケル水酸化物の充填量
が減少するため、いずれの場合も放電容量が低下する。 Further , in the first active material, oxyhydric acid is used.
Cobalt oxide is a dihydroxide based on the atomic conversion ratio of cobalt.
It is added at a rate of 1.0 to 10.0% by weight based on the nickel powder.
And further, in the second active material, oxyhydroxide
Cobalt is oxyhydric acid in terms of the atomic conversion of cobalt.
Ratio of 1.0 to 10.0% by weight based on nickel chloride powder
However, if the coating amount is less than 1.0% by weight,
In that case, the utilization rate of the active material decreases, so the addition amount is 1
If it exceeds 0.0% by weight, the filling amount of nickel hydroxide
Is reduced, the discharge capacity is lowered in any case.
【００２１】活物質を被覆する上記オキシ水酸化コバル
トは、例えば、水酸化コバルトを、酸化剤溶液に水酸化
ナトリウムなどのアルカリを添加した水溶液に、撹拌し
ながら所定時間浸漬して酸化することにより容易に作製
することができる。尚、水酸化コバルトの酸化には、過
酸化水素、次亜塩素酸塩等の強酸化剤の外、ペルオキソ
二硫酸カリウムなどの弱酸化剤も使用することができ
る。The above-mentioned cobalt oxyhydroxide coating the active material is obtained by, for example, oxidizing cobalt hydroxide by immersing it in an aqueous solution in which an alkali such as sodium hydroxide is added to an oxidant solution while stirring for a predetermined time. It can be easily manufactured. For the oxidation of cobalt hydroxide, strong oxidizing agents such as hydrogen peroxide and hypochlorite, and weak oxidizing agents such as potassium peroxodisulfate can be used.
【００２２】水酸化ニッケルのオキシ水酸化ニッケルへ
の酸化、及び水酸化コバルトのオキシ水酸化コバルトへ
の酸化は、それぞれ別々に行ってもよく、また強酸化剤
を使用して、一度に行ってもよい。The oxidation of nickel hydroxide to nickel oxyhydroxide and the oxidation of cobalt hydroxide to cobalt oxyhydroxide may be carried out separately or by using a strong oxidant at once. Good.
【００２３】本発明を適用して好適な密閉型アルカリ蓄
電池用非焼結式ニッケル極としては、導電性芯体に、上
記第１の活物質と第２の活物質とを含有するペーストを
塗布し、乾燥してなるペースト式ニッケル極が挙げられ
る。このときの導電性芯体の具体例としては、ニッケル
発泡体、フェルト状金属繊維多孔体及びパンチングメタ
ルが挙げられる。この外、本発明は、チューブ状の金属
導電体の中に活物質を充填するチューブ状ニッケル極、
ポケット状の金属導電体の中に活物質を充填するポケッ
ト状ニッケル極、活物質を網目状の金属導電体とともに
加圧成形するボタン型電池用ニッケル極などにも、適用
して好適である。As a non-sintered nickel electrode for a sealed alkaline storage battery to which the present invention is preferably applied, a conductive core is coated with a paste containing the first active material and the second active material. Then, a paste-type nickel electrode formed by drying is used. Specific examples of the conductive core at this time include a nickel foam, a felt-like metal fiber porous body, and a punching metal. In addition to this, the present invention is a tubular nickel electrode in which an active material is filled in a tubular metal conductor,
It is also suitably applied to a pocket-shaped nickel electrode in which a pocket-shaped metal conductor is filled with an active material, a nickel electrode for a button-type battery in which an active material is pressure-molded together with a mesh-shaped metal conductor, and the like.
【００２４】本発明電極を正極として用いて好適な密閉
型アルカリ蓄電池の具体例としては、ニッケル−水素蓄
電池（負極：水素吸蔵合金電極）、ニッケル−カドミウ
ム蓄電池（負極：カドミウム電極）及びニッケル−亜鉛
蓄電池（負極：亜鉛電極）が挙げられる。Specific examples of the sealed alkaline storage battery suitable for using the electrode of the present invention as the positive electrode include nickel-hydrogen storage battery (negative electrode: hydrogen storage alloy electrode), nickel-cadmium storage battery (negative electrode: cadmium electrode) and nickel-zinc. A storage battery (negative electrode: zinc electrode) is mentioned.
【００２５】本発明電極では、正極活物質としての水酸
化ニッケルとオキシ水酸化ニッケルを、それぞれ導電剤
としてオキシ水酸化コバルトで被覆しているので、これ
を密閉型アルカリ蓄電池の正極として用いた場合に、第
１の活物質と第２の活物質との混合比率によって、負極
の放電リザーブを自由に制御でき、放電リザーブ量を適
正なものとすることができる。このため、本発明電極を
使用した密閉型アルカリ蓄電池は、高率放電での放電容
量が大きい。In the electrode of the present invention, nickel hydroxide and nickel oxyhydroxide as the positive electrode active material are coated with cobalt oxyhydroxide as the conductive agent, respectively. Therefore, when this is used as the positive electrode of the sealed alkaline storage battery. In addition, the discharge reserve of the negative electrode can be freely controlled by adjusting the mixing ratio of the first active material and the second active material, and the discharge reserve amount can be made appropriate. Therefore, the sealed alkaline storage battery using the electrode of the present invention has a large discharge capacity at high rate discharge.
【００２６】[0026]
【発明の実施の形態】以下、本発明を実施例に基づいて
さらに詳細に説明するが、本発明は下記実施例に何ら限
定されるものではなく、その要旨を変更しない範囲にお
いて適宜変更して実施することが可能なものである。
［実験１］この実験１では、本発明電極の優位性を調べ
るため、従来電極との比較を行った。
（実施例１）
＜第１の活物質の作製＞硫酸コバルト13.1gの水溶液100
0mlに水酸化ニッケル100gを投下し、1モル／リットルの
水酸化ナトリウム水溶液を撹拌しながら滴下して、液の
pHを11に調整する。その後、1時間撹拌混合し、ろ別、
水洗、真空乾燥して、表面を水酸化コバルトで被覆した
水酸化ニッケル粒子粉末を作製した。尚、上記浸漬の
間、液のpHをpHメータ（自動焦点付きガラス電極）にて
監視し、液のpHが低下した時点で、適宜、上記水酸化ナ
トリウム水溶液を滴下してpHを11に保持している。BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited to the following examples, but may be appropriately modified within the scope of the invention. It can be implemented. [Experiment 1] In this experiment 1, in order to examine the superiority of the electrode of the present invention, a comparison with a conventional electrode was performed. (Example 1) <Preparation of first active material> 100% aqueous solution of cobalt sulfate 13.1 g
100 g of nickel hydroxide was dropped into 0 ml, and a 1 mol / liter aqueous solution of sodium hydroxide was added dropwise with stirring to remove the liquid.
Adjust pH to 11. Then, stir and mix for 1 hour, filter and
After washing with water and vacuum drying, nickel hydroxide particle powder having the surface coated with cobalt hydroxide was prepared. During the immersion, the pH of the solution is monitored with a pH meter (glass electrode with automatic focus), and when the pH of the solution drops, the aqueous sodium hydroxide solution is added dropwise to maintain the pH at 11. is doing.
【００２７】上記水酸化コバルトを、オキシ水酸化コバ
ルトへ変化させるには、次の手順で処理をする。先ず、
上記水酸化コバルトで表面を被覆した水酸化ニッケル粒
子粉末100gを、30重量％水酸化ナトリウム1000mlと12重
量％次亜塩素酸ナトリウム水溶液50mlとの混合水溶液
に、撹拌しながら10分間浸漬する。その後、ろ別、水洗
し、乾燥して、オキシ水酸化コバルトで表面を被覆され
たオキシ水酸化ニッケル粒子粉末（第1の活物質）を得
た。In order to change the above cobalt hydroxide into cobalt oxyhydroxide, the treatment is carried out by the following procedure. First,
100 g of the nickel hydroxide particle powder whose surface is coated with cobalt hydroxide is immersed in a mixed aqueous solution of 1000 ml of 30 wt% sodium hydroxide and 50 ml of 12 wt% sodium hypochlorite aqueous solution for 10 minutes while stirring. Then, it was filtered, washed with water, and dried to obtain a nickel oxyhydroxide particle powder (first active material) whose surface was coated with cobalt oxyhydroxide.
【００２８】この第１の活物質において、オキシ水酸化
コバルトは水酸化ニッケルに対し、コバルトの原子換算
で、５重量％添加されている。尚、このオキシ水酸化コ
バルトの含有量は、次のように計算される。In this first active material, cobalt oxyhydroxide is added to nickel hydroxide in an amount of 5% by weight in terms of cobalt atom. The content of this cobalt oxyhydroxide is calculated as follows.
【００２９】オキシ水酸化コバルトの含有量（コバルト
の原子換算による重量％）＝100×〔（硫酸コバルトの
重量）×（コバルト原子の原子量）／（硫酸コバルトの
分子量）〕／（水酸化ニッケルの重量）
＜第２の活物質の作製＞上記第１の活物質の作製におい
て、水酸化コバルトで被覆した水酸化ニッケルからなる
粒子粉末100gを、30重量％水酸化ナトリウム1000ml及び
12重量％次亜塩素酸ナトリウム水溶液1000mlとの混合水
溶液に、撹拌しながら10分間浸漬した。その後、ろ別、
水洗、乾燥して、表面をオキシ水酸化コバルトで被覆し
たオキシ水酸化ニッケル粒子粉末（第２の活物質）を作
製した。上記浸漬処理の際、水酸化コバルト及び水酸化
ニッケルは、それぞれオキシ水酸化コバルト及びオキシ
水酸化ニッケルに酸化されている。Content of cobalt oxyhydroxide (% by weight in terms of cobalt atom) = 100 × [(weight of cobalt sulfate) × (atomic weight of cobalt atom) / (molecular weight of cobalt sulfate)] / (of nickel hydroxide) <Preparation of Second Active Material> In the preparation of the first active material, 100 g of particle powder made of nickel hydroxide coated with cobalt hydroxide was mixed with 1000 ml of 30% by weight sodium hydroxide and
It was immersed in a mixed aqueous solution of 12% by weight aqueous sodium hypochlorite solution (1000 ml) for 10 minutes while stirring. After that,
It was washed with water and dried to prepare a nickel oxyhydroxide particle powder (second active material) whose surface was coated with cobalt oxyhydroxide. During the immersion treatment, cobalt hydroxide and nickel hydroxide are oxidized to cobalt oxyhydroxide and nickel oxyhydroxide, respectively.
【００３０】この第２の活物質において、オキシ水酸化
コバルトはオキシ水酸化ニッケルに対し、コバルトの原
子換算で、５重量％添加されている。尚、このオキシ水
酸化コバルトの含有量は、次のように計算される。In this second active material, cobalt oxyhydroxide was added to nickel oxyhydroxide in an amount of 5 wt% in terms of cobalt atom. The content of this cobalt oxyhydroxide is calculated as follows.
【００３１】オキシ水酸化コバルトの含有量（コバルト
の原子換算による重量％）＝100×〔（硫酸コバルトの
重量）×（コバルト原子の原子量）/（硫酸コバルトの
分子量）〕／（オキシ水酸化ニッケルの重量）
＜非焼結式ニッケル極の作製＞前記＜第１の活物質の作
製＞で得た第１の活物質と、このようにして得られた第
２の活物質とを、重量比80：20で混合した。Content of cobalt oxyhydroxide (% by weight in terms of cobalt atom) = 100 × [(weight of cobalt sulfate) × (atomic weight of cobalt atom) / (molecular weight of cobalt sulfate)] / (nickel oxyhydroxide) <Preparation of non-sintered nickel electrode> The weight ratio of the first active material obtained in <Preparation of first active material> to the second active material thus obtained Mixed at 80:20.
【００３２】この混合粒子100重量部と、結着剤として
の１重量％メチルセルロース水溶液20重量部とを混練し
てペーストを調製し、このペーストを導電性基体である
ニッケル発泡体（多孔度95％、平均孔径200μm）の細孔
内に充填し、乾燥し、加圧成形して、非焼結式ニッケル
極を作製した。
＜密閉型アルカリ蓄電池の作製＞この非焼結式ニッケル
極（正極）、ポリアミド不織布（セパレータ）、30重量
％水酸化カリウム水溶液（電解液）、金属製の電池缶、
金属製の電池蓋などを用いて、AAサイズの密閉型アルカ
リ蓄電池（理論容量：約1000mAh）Ａ１を作製した。正
極容量と負極容量の比を１：２とした。以下の実施例及
び比較例においても、正極容量と負極容量の比はすべて
１：２とした。
（実施例２）硫酸ニッケルと硫酸亜鉛を重量比で99.5：
0.5で混合した水溶液に、硫酸アンモニウム塩を添加
し、ニッケル及び亜鉛のアンミン錯イオンを形成した。
この液を水酸化ナトリウム水溶液に滴下し、亜鉛が0.5
重量％固溶した水酸化ニッケルを作製した。この水酸化
ニッケル100gを用い実施例１と同様の方法で第1の活物
質を得た。第２の活物質は上記実施例１と同じものを用
いた。第１の活物質が異なる以外は、実施例１と同様に
して、非焼結式ニッケル極及び密閉型アルカリ蓄電池Ａ
２を得た。
（実施例３）12重量％次亜塩素酸ナトリウム水溶液に10
00ｍｌに代えて、31重量％過酸化水素水1000ｍｌを使用
したこと以外は実施例１と同様にして、非焼結式ニッケ
ル極及び密閉型アルカリ蓄電池Ａ３を得た。
（比較例1）水酸化ニッケル100重量部と、水酸化コバル
ト7.9重量部（コバルト原子換算で5重量部）と、結着剤
としての1重量％メチルセルロース水溶液20重量部とを
混練してペーストを調整した。このペーストをニッケル
発泡体（多孔度95％、平均孔径200μm）の細孔内に充
填、乾燥し、加圧成形して、非焼結式ニッケル極を作製
した。この非焼結式ニッケル極は、特開昭61-49374号公
報に開示の従来電極である。この非焼結式ニッケル極を
正極として使用したこと以外は実施例１と同様にして、
密閉型アルカリ蓄電池Xを作製した。
（比較例２）水酸化ニッケル100gと一酸化コバルト6.3
ｇとを、比重1.25の水酸化カリウム水溶液1000mlに投入
し、ペルオキソ二硫酸カリウム（K2S2O8）を135gを投入
して1時間混合し、ろ過・水洗後、乾燥して、水酸化ニ
ッケルの粒子表面をオキシ水酸化コバルトで被覆してな
る複合体粒子を作製した。この複合体粒子100重量部
と、結着剤としての１重量％メチルセルロース水溶液20
重量部とを混練してペーストを調整し、このペーストを
ニッケル発泡体（多孔度95％、平均孔径200μm）の細孔
内に充填し、乾燥し、加圧成形して、非焼結式ニッケル
極を作製した。この非焼結式ニッケル極は、特公平8-24
041号公報に開示の従来電極である。この非焼結式ニッ
ケル極を正極として使用したこと以外は実施例１と同様
にして、密閉型アルカリ蓄電池Ｙを作製した。
（比較例３）水酸化ニッケル100gを、30重量％水酸化ナ
トリウム1000mlと12重量％次亜塩素酸ナトリウム水溶液
1000mlとの混合水溶液に、撹拌しながら10分間浸漬した
後、ろ別、水洗し、乾燥してオキシ水酸化ニッケルを作
製した。このようにして得られたオキシ水酸化ニッケル
と水酸化ニッケルを10：90で混合した混合物に、コバル
ト金属を５重量部加えて活物質混合物を得た。この活物
質混合物100重量部と、結着剤としての１重量％メチル
セルロース水溶液20重量部とを混練してペーストを調製
し、このペーストをニッケル発泡体（多孔度95％、平均
孔径200μm）の細孔内に充填、乾燥し、加圧成形して、
非焼結式ニッケル極を作製した。この非焼結式ニッケル
極は、特開昭60-254564号公報に開示の従来電極であ
る。この非焼結式ニッケル極を正極として使用したこと
以外は実施例１と同様にして、密閉型アルカリ蓄電池Ｚ
を作製した。
＜各電池特性の比較＞各電池について25℃にて0.1Ｃで1
6時間充電した後、25℃にて１Ｃで1.0Ｖまで放電する工
程を１サイクルとする充放電を９サイクル行い、各電池
の９サイクル目の放電容量Ｃ１（ｍＡｈ）を求めた。次
いで、各電池を25℃にて0.1Ｃで16時間充電した後、25
℃にて４Ｃで1.0Vまで放電して、各電池の10サイクル目
の放電容量Ｃ２（ｍＡｈ）を求めた。各電池について、
放電容量Ｃ１に対する放電容量Ｃ２の比率Ｐ（％）を算
出した。比率Ｐは、各電池の高率放電特性の良否を示す
指標であり、この値が大きいほど、高率放電特性が良
い。結果を表１に示す。表１中の各電池の９サイクル目
の放電容量は、電池Ａ１の９サイクル目の放電容量を10
0とした相対指数である。100 parts by weight of the mixed particles and 20 parts by weight of a 1% by weight aqueous solution of methylcellulose as a binder were kneaded to prepare a paste, and the paste was prepared by using a nickel foam (porosity 95%) as a conductive substrate. , An average pore diameter of 200 μm) was filled, dried and pressure-molded to prepare a non-sintered nickel electrode. <Production of sealed alkaline storage battery> This non-sintered nickel electrode (positive electrode), polyamide nonwoven fabric (separator), 30 wt% potassium hydroxide aqueous solution (electrolyte), metal battery can,
AA size sealed alkaline storage battery (theoretical capacity: about 1000 mAh) A1 was produced using a metal battery lid and the like. The ratio between the positive electrode capacity and the negative electrode capacity was 1: 2. Also in the following examples and comparative examples, the ratio of the positive electrode capacity to the negative electrode capacity was all set to 1: 2. (Example 2) Nickel sulfate and zinc sulfate in a weight ratio of 99.5:
Ammonium sulfate salt was added to the aqueous solution mixed at 0.5 to form an ammine complex ion of nickel and zinc.
This solution was added dropwise to an aqueous solution of sodium hydroxide, and the zinc content was 0.5.
A nickel hydroxide having a solid solution by weight% was prepared. A first active material was obtained in the same manner as in Example 1 using 100 g of this nickel hydroxide. The same second active material as in Example 1 was used. A non-sintered nickel electrode and a sealed alkaline storage battery A were prepared in the same manner as in Example 1 except that the first active material was different.
Got 2. (Example 3) 10% by weight in a 12% by weight aqueous solution of sodium hypochlorite
A non-sintered nickel electrode and a sealed alkaline storage battery A3 were obtained in the same manner as in Example 1 except that 1000 ml of 31 wt% hydrogen peroxide solution was used instead of 00 ml. (Comparative Example 1) 100 parts by weight of nickel hydroxide, 7.9 parts by weight of cobalt hydroxide (5 parts by weight in terms of cobalt atom), and 20 parts by weight of a 1% by weight methylcellulose aqueous solution as a binder were kneaded to form a paste. It was adjusted. This paste was filled in the pores of a nickel foam (porosity 95%, average pore diameter 200 μm), dried and pressure-molded to produce a non-sintered nickel electrode. This non-sintered nickel electrode is a conventional electrode disclosed in JP-A-61-49374. In the same manner as in Example 1 except that this non-sintered nickel electrode was used as the positive electrode,
A sealed alkaline storage battery X was produced. (Comparative Example 2) Nickel hydroxide 100 g and cobalt monoxide 6.3
g and 1000 g of potassium hydroxide aqueous solution with a specific gravity of 1.25, 135 g of potassium peroxodisulfate (K 2 S 2 O 8 ) and mixed for 1 hour, filtered, washed with water, dried and hydrated. Composite particles were prepared by coating the surface of nickel particles with cobalt oxyhydroxide. 100 parts by weight of the composite particles and a 1% by weight aqueous solution of methylcellulose as a binder 20
A paste is prepared by kneading with parts by weight, and the paste is filled into the pores of a nickel foam (porosity 95%, average pore size 200 μm), dried, pressure-molded, and non-sintered nickel is used. The pole was made. This non-sintered nickel electrode is
This is the conventional electrode disclosed in Japanese Patent No. 041. A sealed alkaline storage battery Y was produced in the same manner as in Example 1 except that this non-sintered nickel electrode was used as the positive electrode. (Comparative Example 3) Nickel hydroxide 100 g, 30% by weight sodium hydroxide 1000 ml and 12% by weight sodium hypochlorite aqueous solution
After immersing in a mixed aqueous solution with 1000 ml for 10 minutes while stirring, it was filtered, washed with water, and dried to prepare nickel oxyhydroxide. 5 parts by weight of cobalt metal was added to the mixture of nickel oxyhydroxide and nickel hydroxide obtained in this manner at 10:90 to obtain an active material mixture. A paste was prepared by kneading 100 parts by weight of this active material mixture and 20 parts by weight of a 1% by weight methylcellulose aqueous solution as a binder, and using this paste, a fine nickel foam (porosity 95%, average pore diameter 200 μm) was prepared. Fill the hole, dry, press mold,
A non-sintered nickel electrode was produced. This non-sintered nickel electrode is a conventional electrode disclosed in JP-A-60-254564. A sealed alkaline storage battery Z was prepared in the same manner as in Example 1 except that this non-sintered nickel electrode was used as the positive electrode.
Was produced. <Comparison of each battery characteristics> For each battery, 1 at 0.1C at 25 ℃
After charging for 6 hours, charging / discharging was performed for 9 cycles, with one cycle consisting of discharging at 1C to 1.0V at 25 ° C, and the discharge capacity C1 (mAh) at the 9th cycle of each battery was obtained. Then, charge each battery at 25 ° C for 16 hours at 0.1C, then
The battery was discharged to 1.0 V at 4 ° C. and the discharge capacity C2 (mAh) at the 10th cycle of each battery was obtained. For each battery,
The ratio P (%) of the discharge capacity C2 to the discharge capacity C1 was calculated. The ratio P is an index indicating whether the high rate discharge characteristic of each battery is good or bad. The larger this value, the better the high rate discharge characteristic. The results are shown in Table 1. The discharge capacity at 9th cycle of each battery in Table 1 is the discharge capacity at 9th cycle of battery A1.
It is a relative index with 0.
【００３３】[0033]
【表１】 [Table 1]
【００３４】表１に示すように、電池Ａ１〜Ａ３は、電
池Ｘ、Ｙ、Ｚに比べて、９サイクル目の放電容量が大き
く、しかも比率Ｐが大きい。この結果から、本発明電極
を使用することにより、従来電極を使用した場合に比べ
て、高率放電での放電容量が大きい密閉型アルカリ蓄電
池が得られることが分かる。
[実験２]この実験２では、第１の活物質、第２の活物質
に混合する添加元素の種類を代えて、電極特性、電池特
性を比較した。
（実施例４:第１の活物質への添加元素を変化させた場
合）上記実験１の実施例２における硫酸亜鉛に代えて、
マグネシウム(Mg)、カルシウム(Ca)、マンガン(Mn)、ア
ルミニウム(Al)、カドミウム(Cd)、イットリウム(Ｙ)、
コバルト(Co)、ビスマス(Bi)、ランタン(La)、イッテル
ビウム(Yb)、エルビウム(Er)、ガドリニウム(Gd)、セリ
ウム(Ce)の硫酸塩を用いたこと以外は実施例２と同様に
して、非焼結式ニッケル極及びアルカリ蓄電池Ｂ１〜Ｂ
13を得た。
（実施例５：第２の活物質への添加元素を変化させた場
合）硫酸ニッケルと硫酸亜鉛を重量比で99.5：0.5で混
合した水溶液に、硫酸アンモニウム塩を添加し、ニッケ
ル及び亜鉛のアンミン錯イオンを形成した。この液を水
酸化ナトリウム水溶液に滴下し、亜鉛が0.5重量％固溶
した水酸化ニッケルを作製した。この水酸化ニッケル10
0gを用い、上記実施例１と同様の方法で、第1及び第２
の活物質を得た。活物質が異なる以外は、実施例１と同
様にして、非焼結式ニッケル極及び密閉型アルカリ蓄電
池Ｂ14を得た。
（実施例６）上記実施例５において硫酸亜鉛に代えて、
硫酸マグネシウムを用いたこと以外は上記実施例５と同
様にして、非焼結式ニッケル極及びアルカリ蓄電池Ｂ15
を得た。
（実施例７）上記実施例５において、硫酸ニッケル、硫
酸亜鉛及び硫酸コバルトを重量比で99：0.5：0.5で混合
して亜鉛及びコバルトが0.5重量％ずつ固溶した水酸化
ニッケルを作製したこと以外は上記実施例５と同様にし
て非焼結式ニッケル極及び密閉型アルカリ蓄電池Ｂ16を
得た。As shown in Table 1, the batteries A1 to A3 have a larger discharge capacity at the ninth cycle and a larger ratio P than the batteries X, Y, and Z. From this result, it can be seen that by using the electrode of the present invention, a sealed alkaline storage battery having a large discharge capacity at high rate discharge can be obtained as compared with the case of using the conventional electrode. [Experiment 2] In Experiment 2, the electrode characteristics and the battery characteristics were compared by changing the types of the additive elements mixed in the first active material and the second active material. (Example 4: When the additive element to the first active material is changed) Instead of zinc sulfate in Example 2 of Experiment 1 described above,
Magnesium (Mg), Calcium (Ca), Manganese (Mn), Aluminum (Al), Cadmium (Cd), Yttrium (Y),
Same as Example 2 except that cobalt (Co), bismuth (Bi), lanthanum (La), ytterbium (Yb), erbium (Er), gadolinium (Gd), and cerium (Ce) sulfate were used. , Non-sintered nickel electrode and alkaline storage batteries B1 to B
Got 13. (Example 5: When the element added to the second active material was changed) An ammonium sulfate salt was added to an aqueous solution in which nickel sulfate and zinc sulfate were mixed at a weight ratio of 99.5: 0.5 to form an ammine complex of nickel and zinc. Ions were formed. This solution was added dropwise to an aqueous sodium hydroxide solution to prepare nickel hydroxide in which 0.5% by weight of zinc was solid-solved. This nickel hydroxide 10
In the same manner as in Example 1 above using 0 g, the first and second
To obtain the active material. A non-sintered nickel electrode and a sealed alkaline storage battery B14 were obtained in the same manner as in Example 1 except that the active material was different. (Example 6) Instead of zinc sulfate in the above Example 5,
Non-sintered nickel electrode and alkaline storage battery B15 were used in the same manner as in Example 5 except that magnesium sulfate was used.
Got Example 7 In Example 5, nickel sulfate, zinc sulfate and cobalt sulfate were mixed at a weight ratio of 99: 0.5: 0.5 to prepare nickel hydroxide in which zinc and cobalt were dissolved in 0.5% by weight. A non-sintered nickel electrode and a sealed alkaline storage battery B16 were obtained in the same manner as in Example 5 except above.
【００３５】これらの電池を準備し、前記実験１と同様
にして、電池特性を比較した。この結果を、表２に示
す。These batteries were prepared and battery characteristics were compared in the same manner as in Experiment 1. The results are shown in Table 2.
【００３６】[0036]
【表２】 [Table 2]
【００３７】この結果より、第１の活物質及び第２の活
物質共に添加元素がない電池Ａ１よりも、第１の活物質
に添加元素を加えた電池Ａ１、Ｂ１〜Ｂ13、更には、第
1及び第２の活物質に添加元素を加えた電池Ｂ14、Ｂ1
5、及び第1及び第２の活物質に複数の添加元素を加えた
電池Ｂ16は、優れた電池特性を有することが理解され
る。
[実験３]この実験３では、水酸化ニッケルとオキシ水酸
化ニッケルの混合比率、即ち第１の活物質と第２の活物
質との混合比率と、電池の高率放電特性の関係を調べ
た。From these results, the batteries A1, B1 to B13 in which the additive element was added to the first active material, and further the battery A1 in which the additive element was added to the first active material,
Batteries B14 and B1 in which additional elements are added to the first and second active materials
It is understood that the battery B16 in which a plurality of additive elements are added to the fifth active material and the first and second active materials has excellent battery characteristics. [Experiment 3] In Experiment 3, the relationship between the mixing ratio of nickel hydroxide and nickel oxyhydroxide, that is, the mixing ratio of the first active material and the second active material, and the high rate discharge characteristics of the battery was investigated. .
【００３８】先ず、オキシ水酸化コバルトで被覆した水
酸化ニッケル（第１の活物質）と、オキシ水酸化コバル
トで被覆したオキシ水酸化ニッケル（第２の活物質）の
混合比を、前記実施例１の重量比80：20に代えて、95：
５、90：10、70：30、60：40、50：50（５種類）とした
混合物を作製した。正極活物質としてこの５種類の混合
物を使用したこと以外は、上記実施例１と同様にして、
密閉型アルカリ蓄電池Ｃ１〜Ｃ５を作製した。各電池に
ついて、先の実験１と同じ条件の充放電サイクル試験を
行い、各電池の９サイクル目の放電容量Ｃ１に対する９
サイクル目の放電容量の比率Ｐを求めた。この結果を表
３に示す。表３には電池Ａ１の結果も示してあり、表３
中のＱは、電池Ａ１の９サイクル目の放電容量Ｃ１に対
する10サイクル目の放電容量の比率Ｐ（89％）を100と
した相対指数である。Ｑの値が大きい電池ほど、高率放
電特性が良い。First, the mixing ratio of the nickel oxyhydroxide coated with cobalt oxyhydroxide (first active material) and the nickel oxyhydroxide coated with cobalt oxyhydroxide (second active material) was determined as in the above-mentioned example. Instead of the weight ratio of 80:20 of 1, 95:
5, 90:10, 70:30, 60:40, 50:50 (5 types) were prepared as a mixture. In the same manner as in Example 1 except that the mixture of these 5 types was used as the positive electrode active material,
The sealed alkaline storage batteries C1 to C5 were produced. Each battery was subjected to a charge / discharge cycle test under the same conditions as in Experiment 1 above, and the discharge capacity C1 at the 9th cycle of each battery was 9%.
The ratio P of the discharge capacity at the cycle was calculated. The results are shown in Table 3. Table 3 also shows the results for Battery A1.
Q in the table is a relative index with 100 being the ratio P (89%) of the discharge capacity at the 10th cycle to the discharge capacity C1 at the 9th cycle of the battery A1. A battery having a larger Q value has better high rate discharge characteristics.
【００３９】[0039]
【表３】 [Table 3]
【００４０】表３に示すように、電池Ａ１、Ｃ２〜Ｃ４
は、電池Ｃ１に比べて、Ｑの値が大きい。電池Ｃ５は３
サイクル目の充放電後、50ｍｇの重量減少が生じたため
試験を中断した。この結果から、高率放電特性が良い密
閉型アルカリ蓄電池を与える非焼結式ニッケル極を得る
ためには、水酸化ニッケル（第１の活物質）とオキシ水
酸化ニッケル（第２の活物質）とを、重量比率90：10〜
60：40で混合した活物質を使用するのが良い。As shown in Table 3, batteries A1, C2 to C4
Has a larger Q value than the battery C1. Battery C5 is 3
After the charge and discharge of the cycle, the test was interrupted because a weight loss of 50 mg occurred. From this result, in order to obtain a non-sintered nickel electrode that provides a sealed alkaline storage battery with good high rate discharge characteristics, nickel hydroxide (first active material) and nickel oxyhydroxide (second active material) were obtained. And the weight ratio 90:10 ~
It is better to use the active material mixed at 60:40.
【００４１】そして、この中でも特に第１の活物質と第
２の活物質との混合比を、重量比率で80：20〜70：30と
した活物質を用いた電池Ａ１、Ｃ３は放電容量が最大と
なっており、最適範囲といえる。
[実験４]この実験４では、第１の活物質において、水酸
化ニッケルに対するオキシ水酸化コバルトのコバルト原
子換算での比率を変化させ、電池の放電容量との関係を
調べた。尚、第２の活物質におけるオキシ水酸化ニッケ
ルに対するオキシ水酸化コバルトの比率は、コバルト原
子換算で５重量％に固定してある。また、第１の活物質
と第２の活物質の重量比率は、80：20に固定してある。Among them, the batteries A1 and C3 using the active material in which the mixing ratio of the first active material and the second active material is 80:20 to 70:30 in weight ratio have discharge capacity. It is the maximum and can be said to be the optimum range. [Experiment 4] In Experiment 4, the ratio of cobalt oxyhydroxide to nickel hydroxide in terms of cobalt atom in the first active material was changed to examine the relationship with the discharge capacity of the battery. The ratio of cobalt oxyhydroxide to nickel oxyhydroxide in the second active material is fixed at 5% by weight in terms of cobalt atom. The weight ratio of the first active material to the second active material is fixed at 80:20.
【００４２】オキシ水酸化コバルトを被覆した水酸化ニ
ッケル（第１の活物質）を作製する際の硫酸コバルトの
使用量を13.1ｇ（コバルト原子換算で５重量％に相当）
に代えて、0.78ｇ、1.3ｇ、2.7ｇ、7.8ｇ、18.3ｇ、26.
3ｇ、31.5ｇ及び39.4ｇ（コバルト原子換算で、順に、
0.3重量％、0.5重量％、1.0重量％、3.0重量％、7.0重
量％、10.0重量％、12.0重量％及び15.0重量％）とした
こと以外は実施例１と同様にして、順にアルカリ蓄電池
Ｄ１〜Ｄ８を作製した。詳細を、電池Ａ１の結果と併せ
て、表４に示す。The amount of cobalt sulfate used for producing nickel hydroxide (first active material) coated with cobalt oxyhydroxide was 13.1 g (equivalent to 5% by weight in terms of cobalt atom).
Instead of 0.78g, 1.3g, 2.7g, 7.8g, 18.3g, 26.
3g, 31.5g and 39.4g (in terms of cobalt atom, in order,
0.3% by weight, 0.5% by weight, 1.0% by weight, 3.0% by weight, 7.0% by weight, 10.0% by weight, 12.0% by weight and 15.0% by weight) in the same manner as in Example 1, except that the alkaline storage batteries D1 to D8 was produced. Details are shown in Table 4 together with the result of the battery A1.
【００４３】[0043]
【表４】 [Table 4]
【００４４】上記各電池について、先と同じ条件の充放
電サイクル試験を行い、各電池の９サイクル目の放電容
量Ｃ１を求めた。この結果を図１に示す。A charging / discharging cycle test under the same conditions as above was carried out for each of the above batteries, and the discharge capacity C1 at the 9th cycle of each battery was determined. The result is shown in FIG.
【００４５】図１において、縦軸は９サイクル目の放電
容量を、横軸は第１の活物質において水酸化ニッケルに
対するオキシ水酸化コバルトのコバルト原子換算での比
率（重量％）を、それぞれ示す。尚、この縦軸は、電池
Ａ１の９サイクル目の放電容量を100とした相対指数で
表している。In FIG. 1, the vertical axis represents the discharge capacity at the 9th cycle, and the horizontal axis represents the ratio (% by weight) of cobalt oxyhydroxide to nickel hydroxide in the first active material in terms of cobalt atoms. . The vertical axis represents the relative index with the discharge capacity at the 9th cycle of the battery A1 as 100.
【００４６】図１より、放電容量の大きい非焼結式ニッ
ケル極を得るためには、第１の活物質において、水酸化
ニッケルに対するオキシ水酸化コバルトのコバルト原子
換算での比率を、1.0〜10.0重量％とする必要があるこ
とが分かる。
[実験５]この実験５では、第２の活物質において、オキ
シ水酸化ニッケルに対するオキシ水酸化コバルトのコバ
ルト原子換算での比率を変化させ、電池の放電容量との
関係を調べた。尚、第１の活物質における水酸化ニッケ
ルに対するオキシ水酸化コバルトの比率は、コバルト原
子換算で５重量％に固定してある。また、第１の活物質
と第２の活物質の重量比率は、80：20に固定してある。From FIG. 1, in order to obtain a non-sintered nickel electrode having a large discharge capacity, in the first active material, the ratio of cobalt oxyhydroxide to nickel hydroxide in terms of cobalt atom was 1.0 to 10.0. It can be seen that it is necessary to set the weight percentage. [Experiment 5] In Experiment 5, the ratio of cobalt oxyhydroxide to nickel oxyhydroxide in terms of cobalt atom was changed in the second active material, and the relationship with the discharge capacity of the battery was investigated. The ratio of cobalt oxyhydroxide to nickel hydroxide in the first active material was fixed at 5% by weight in terms of cobalt atom. The weight ratio of the first active material to the second active material is fixed at 80:20.
【００４７】オキシ水酸化コバルトで被覆したオキシ水
酸化ニッケル（第２の活物質）を作製する際の硫酸コバ
ルトの使用量を13.1ｇ（コバルト原子換算で５重量％に
相当）に代えて、0.78ｇ、1.3ｇ、2.7ｇ、7.8ｇ、18.3
ｇ、26.3ｇ、31.5ｇ及び39.4ｇ（コバルト原子換算で、
順に、0.3重量％、0.5重量％、1.0重量％、3.0重量％、
7.0重量％、10.0重量％、12.0重量％及び15.0重量％）
としたこと以外は実施例１と同様にして、順にアルカリ
蓄電池Ｅ１〜Ｅ８を作製した。詳細を、電池Ａ１の結果
と併せて、表５に示す。When the nickel oxyhydroxide coated with cobalt oxyhydroxide (second active material) was prepared, the amount of cobalt sulfate used was changed to 13.1 g (corresponding to 5 wt% in terms of cobalt atom), and 0.78 g, 1.3g, 2.7g, 7.8g, 18.3
g, 26.3g, 31.5g and 39.4g (cobalt atom equivalent,
0.3% by weight, 0.5% by weight, 1.0% by weight, 3.0% by weight,
7.0 wt%, 10.0 wt%, 12.0 wt% and 15.0 wt%)
Alkaline storage batteries E1 to E8 were sequentially manufactured in the same manner as in Example 1 except for the above. Details are shown in Table 5 together with the result of the battery A1.
【００４８】[0048]
【表５】 [Table 5]
【００４９】上記各電池について、先と同じ条件の充放
電サイクル試験を行い、各電池の９サイクル目の放電容
量Ｃ１を求めた。この結果を図２に示す。A charge / discharge cycle test under the same conditions as above was carried out for each of the above batteries, and the discharge capacity C1 at the 9th cycle of each battery was determined. The result is shown in FIG.
【００５０】図２において、縦軸は９サイクル目の放電
容量を、横軸は第２の活物質においてオキシ水酸化ニッ
ケルに対するオキシ水酸化コバルトのコバルト原子換算
での比率（重量％）を、それぞれ示す。尚、図２の縦軸
は、電池Ａ１の９サイクル目の放電容量を100とした相
対指数で表している。In FIG. 2, the vertical axis represents the discharge capacity at the 9th cycle, and the horizontal axis represents the ratio of cobalt oxyhydroxide to nickel oxyhydroxide in the second active material in terms of cobalt atom (wt%). Show. The vertical axis of FIG. 2 is represented by a relative index with the discharge capacity at the 9th cycle of the battery A1 as 100.
【００５１】図２より、放電容量の大きい非焼結式ニッ
ケル極を得るためには、第２の活物質において、オキシ
水酸化ニッケルに対するオキシ水酸化コバルトのコバル
ト原子換算での比率を、1.0〜10.0重量％とするのが望
ましい。From FIG. 2, in order to obtain a non-sintered nickel electrode having a large discharge capacity, in the second active material, the ratio of cobalt oxyhydroxide to cobalt oxyhydroxide in terms of cobalt atom is 1.0 to. It is preferably 10.0% by weight.
【００５２】[0052]
【発明の効果】本発明により、高率放電での放電容量が
大きい密閉型アルカリ蓄電池を与える非焼結式ニッケル
極が提供される。The present invention provides a non-sintered nickel electrode which provides a sealed alkaline storage battery having a large discharge capacity at high rate discharge.
【図１】第１の活物質における、水酸化ニッケルに対す
るオキシ水酸化コバルトのコバルト原子換算での比率
と、電池の放電容量の関係を示すグラフである。FIG. 1 is a graph showing the relationship between the ratio of cobalt oxyhydroxide to nickel hydroxide in terms of cobalt atoms and the discharge capacity of a battery in the first active material.
【図２】第２の活物質における、オキシ水酸化ニッケル
に対するオキシ水酸化コバルトのコバルト原子換算での
比率と、電池の放電容量の関係を示すグラフである。FIG. 2 is a graph showing the relationship between the ratio of cobalt oxyhydroxide to nickel oxyhydroxide in terms of cobalt atoms in the second active material and the discharge capacity of the battery.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 木本 衛 大阪府守口市京阪本通２丁目５番５号 三洋電機株式会社内 (72)発明者 藤谷 伸 大阪府守口市京阪本通２丁目５番５号 三洋電機株式会社内 (72)発明者 西尾 晃治 大阪府守口市京阪本通２丁目５番５号 三洋電機株式会社内 (56)参考文献 特開 平９−219191（ＪＰ，Ａ) 特開 昭60−254564（ＪＰ，Ａ) 特開 昭59−16271（ＪＰ，Ａ) 特開 平８−203516（ＪＰ，Ａ) 特開 平３−78965（ＪＰ，Ａ) 特公 平８−24041（ＪＰ，Ｂ２) (58)調査した分野(Int.Cl.7，ＤＢ名) H01M 4/00 - 4/62 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mamoru Kimoto 2-5-5 Keihan Hondori, Moriguchi City, Osaka Prefecture Sanyo Electric Co., Ltd. (72) Shin Shin Fujitani 2-5 Keihan Hondori, Moriguchi City, Osaka Prefecture No. 5 within Sanyo Electric Co., Ltd. (72) Inventor Koji Nishio 2-5-5 Keihan Hondori, Moriguchi City, Osaka Sanyo Electric Co., Ltd. (56) Reference JP-A-9-219191 (JP, A) Kai 60-254564 (JP, A) JP 59-16271 (JP, A) JP 8-203516 (JP, A) JP 3-78965 (JP, A) JP 8-24041 ( JP, B2) (58) Fields investigated (Int.Cl. 7 , DB name) H01M 4/00-4/62
Claims (5)
被覆した第１の活物質と、オキシ水酸化ニッケルをオキ
シ水酸化コバルトで被覆した第２の活物質とを９０：１
０〜６０：４０の重量比率で混合した活物質が用いられ
ており、かつ、 前記第１の活物質において、オキシ水酸化コバルトが、
コバルトの原子換算での比率で水酸化ニッケル粉末に対
して１．０〜１０．０重量％の割合で添加され、かつ、 前記第２の活物質において、オキシ水酸化コバルトが、
コバルトの原子換算での比率でオキシ水酸化ニッケル粉
末に対して１．０〜１０．０重量％の割合で添加されて
いることを特徴とする密閉型アルカリ蓄電池用非焼結式
ニッケル極 。1. A first active material in which nickel hydroxide is coated with cobalt oxyhydroxide and a second active material in which nickel oxyhydroxide is coated with cobalt oxyhydroxide are 90: 1.
Active materials mixed in a weight ratio of 0 to 60:40 are used.
And in the first active material, cobalt oxyhydroxide is
Amount of nickel hydroxide powder in terms of the atomic conversion of cobalt
And added in a ratio of 1.0 to 10.0% by weight, and in the second active material, cobalt oxyhydroxide is added .
Nickel oxyhydroxide powder in atomic conversion ratio of cobalt
It is added in the ratio of 1.0-10.0% by weight to the powder
Non-sintered type for sealed alkaline storage batteries characterized by
Nickel pole .
８０：２０〜７０：３０の重量比率で混合した活物質が
用いられていることを特徴とする、請求項１記載のアル
カリ蓄電池用非焼結式ニッケル極。 2. The first active material and the second active material
The active material mixed in a weight ratio of 80:20 to 70:30 is
Al according to claim 1, characterized in that it is used.
Non-sintered nickel electrode for potassium storage battery.
ルが、亜鉛、マグネシウム、カルシウム、マンガン、ア
ルミニウム、カドミウム、イットリウム、コバルト、ビ
スマス、ランタン、イッテルビウム、エルビウム、ガド
リニウム及びセリウムからなる群から選択された少なく
とも１種の元素を含有することを特徴とする請求項１又
は請求項２記載の密閉型アルカリ蓄電池用非焼結式ニッ
ケル極。 3. The nickel hydroxide according to claim 1, wherein the first active material is nickel hydroxide.
Are zinc, magnesium, calcium, manganese,
Luminium, Cadmium, Yttrium, Cobalt, Bi
Muss, lantern, ytterbium, erbium, gad
Less selected from the group consisting of rhinium and cerium
Both of them contain one kind of element.
Is a non-sintered type nickel for a sealed alkaline storage battery according to claim 2.
Kell pole.
ニッケルが、亜鉛、マグネシウム、カルシウム、マンガ
ン、アルミニウム、カドミウム、イットリウム、コバル
ト、ビスマス、ランタン、イッテルビウム、エルビウ
ム、ガドリニウム及びセリウムからなる群から選択され
た少なくとも１種の元素を含有することを特徴とする請
求項１又は請求項２記載の密閉型アルカリ蓄電池用非焼
結式ニッケル極。 4. The oxyhydroxylation in the second active material
Nickel is zinc, magnesium, calcium, manga
Aluminum, Cadmium, Yttrium, Cobal
To, bismuth, lantern, ytterbium, erbiu
Selected from the group consisting of aluminum, gadolinium and cerium.
A contract characterized by containing at least one element
Non-baking for sealed alkaline storage battery according to claim 1 or claim 2.
Type nickel electrode.
ッケル極を用いた密閉型アルカリ蓄電池。 5. The non-sintered type D according to claim 1 or 2.
A sealed alkaline storage battery that uses a nickel pole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01940898A JP3469766B2 (en) | 1998-01-30 | 1998-01-30 | Non-sintered nickel electrodes and batteries for sealed alkaline storage batteries |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01940898A JP3469766B2 (en) | 1998-01-30 | 1998-01-30 | Non-sintered nickel electrodes and batteries for sealed alkaline storage batteries |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH11219701A JPH11219701A (en) | 1999-08-10 |
| JP3469766B2 true JP3469766B2 (en) | 2003-11-25 |
Family
ID=11998440
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP01940898A Expired - Lifetime JP3469766B2 (en) | 1998-01-30 | 1998-01-30 | Non-sintered nickel electrodes and batteries for sealed alkaline storage batteries |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3469766B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007095358A (en) * | 2005-09-27 | 2007-04-12 | Sanyo Electric Co Ltd | Positive plate for alkaline secondary battery |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3429741B2 (en) * | 2000-03-24 | 2003-07-22 | 松下電器産業株式会社 | Paste positive electrode for alkaline storage batteries and nickel-metal hydride storage batteries |
| JP3558590B2 (en) | 2000-07-14 | 2004-08-25 | 松下電器産業株式会社 | Method for producing positive electrode active material for alkaline storage battery |
| JP3510582B2 (en) * | 2000-10-31 | 2004-03-29 | 川崎重工業株式会社 | 3D battery |
| CN1307739C (en) * | 2001-03-05 | 2007-03-28 | 株式会社汤浅 | Method for manufacturing nickel hydrogen battery |
| JP4765195B2 (en) * | 2001-05-10 | 2011-09-07 | ソニー株式会社 | Positive electrode active material, method for producing positive electrode active material, positive electrode for battery, and battery |
| JP4972312B2 (en) * | 2005-12-14 | 2012-07-11 | Ｆｄｋエナジー株式会社 | Alkaline battery |
-
1998
- 1998-01-30 JP JP01940898A patent/JP3469766B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007095358A (en) * | 2005-09-27 | 2007-04-12 | Sanyo Electric Co Ltd | Positive plate for alkaline secondary battery |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH11219701A (en) | 1999-08-10 |
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