JP2000311680A - Sintered type positive electrode plate for nickel- hydrogen battery, its manufacture and nickel-hydrogen battery - Google Patents
Sintered type positive electrode plate for nickel- hydrogen battery, its manufacture and nickel-hydrogen batteryInfo
- Publication number
- JP2000311680A JP2000311680A JP11117854A JP11785499A JP2000311680A JP 2000311680 A JP2000311680 A JP 2000311680A JP 11117854 A JP11117854 A JP 11117854A JP 11785499 A JP11785499 A JP 11785499A JP 2000311680 A JP2000311680 A JP 2000311680A
- Authority
- JP
- Japan
- Prior art keywords
- nickel
- electrode plate
- positive electrode
- hydroxide
- metal hydride
- 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.)
- Pending
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
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- Battery Electrode And Active Subsutance (AREA)
- Cell Electrode Carriers And Collectors (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、ニッケル水素電池
用焼結型正極板とその製造方法およびニッケル水素電池
に関するものである。The present invention relates to a sintered positive electrode plate for a nickel-metal hydride battery, a method for producing the same, and a nickel-metal hydride battery.
【０００２】[0002]
【従来の技術】ニッケル水素電池の焼結型正極板に用い
る多孔性基板は、一般的に、鋼板上にニッケルめっきを
施した芯材に、ニッケル粉末を増粘剤となる樹脂成分と
共にスラリーにして塗布・乾燥した後、水素を含む還元
雰囲気中で焼結することによって製造される。量産性の
観点から、通常は、長尺の芯材を用いてロールトゥーロ
ール(roll to roll)での連続生産が行われている。ニッ
ケル水素用焼結型正極板は、このようにして得られた多
孔性焼結基板の空孔内に活物質となる水酸化ニッケルを
充填した後、化成処理を経て、単セルのサイズに切断す
ることにより製造される。2. Description of the Related Art Generally, a porous substrate used for a sintered positive electrode plate of a nickel-metal hydride battery is formed by slurrying nickel powder together with a resin component serving as a thickener on a core material obtained by plating nickel on a steel plate. After being applied and dried, it is manufactured by sintering in a reducing atmosphere containing hydrogen. From the viewpoint of mass production, continuous production is usually performed by roll-to-roll using a long core material. The sintered positive electrode plate for nickel-metal hydride is cut into single cell size after filling the pores of the porous sintered substrate thus obtained with nickel hydroxide, which is the active material, and then undergoing a chemical conversion treatment. It is manufactured by doing.
【０００３】前記のようにして製造される従来のニッケ
ル水素電池の焼結型正極板は、放置時の吸湿により水酸
化ニッケルの異常析出が起こる。そして、特に極板表面
部分に析出した水酸化ニッケルは、電池構成時にセパレ
ーターを突き破り、負極と接触するため、リーク不良の
原因になっている。[0003] In the sintered positive electrode plate of a conventional nickel-metal hydride battery manufactured as described above, abnormal precipitation of nickel hydroxide occurs due to moisture absorption during standing. In addition, nickel hydroxide precipitated particularly on the surface of the electrode plate breaks through the separator during the construction of the battery and comes into contact with the negative electrode, thereby causing a leak failure.
【０００４】水酸化ニッケルの異常析出の要因は、以下
のように推定される。すなわち、芯材である鋼鈑はニッ
ケルめっきを施されているが、部分的にピンホールがあ
ったり、活物質の充填プロセスで、酸によるニッケルめ
っき膜の腐食のために鉄が露出した部分が存在する。ま
た、単セルに切断された端部においても芯材の鉄が露出
することになる。鉄とオキシ水酸化ニッケルは局部電池
を形成しやすく、鉄が露出した焼結型正極板が吸湿する
と、局部カソードとなるオキシ水酸化ニッケルの還元反
応と、局部アノードとなる鉄の溶解反応が起こる。鉄が
溶解すると、鉄と水酸イオンによる錯体の形成により、
鉄露出部の近傍の液相は酸性を呈する。液相が酸性を呈
することにより、焼結体を構成するニッケルの溶解が促
進される。ニッケルイオンも水酸イオンと錯体を形成す
るが、溶解度積が小さいため水酸化ニッケルが直ちに沈
殿する。ニッケル（比重：８．８５）の溶解に起因する
水酸化ニッケル（比重：３．６５）の沈殿析出では、体
積膨張が起こるため、水酸化ニッケルは多孔性基板の表
面部分に押し出される。The cause of abnormal precipitation of nickel hydroxide is presumed as follows. In other words, the steel plate as the core material is nickel-plated, but there are some pinholes, and in the process of filling the active material, the portion where iron is exposed due to the corrosion of the nickel plating film by acid is removed. Exists. In addition, the core iron is also exposed at the ends cut into the single cells. Iron and nickel oxyhydroxide easily form a local battery, and when the sintered positive electrode plate with exposed iron absorbs moisture, a reduction reaction of nickel oxyhydroxide that becomes a local cathode and a dissolution reaction of iron that becomes a local anode occur . When iron dissolves, a complex is formed by iron and hydroxyl ions,
The liquid phase near the exposed part of the iron exhibits acidity. When the liquid phase exhibits acidity, dissolution of nickel constituting the sintered body is promoted. Nickel ions also form complexes with hydroxide ions, but nickel hydroxide precipitates immediately because of its low solubility product. In the precipitation of nickel hydroxide (specific gravity: 3.65) caused by dissolution of nickel (specific gravity: 8.85), volume expansion occurs, so that nickel hydroxide is extruded to the surface of the porous substrate.
【０００５】このように、従来技術によるニッケル水素
電池用焼結型正極板では、放置時の吸湿により水酸化ニ
ッケルが異常析出し、セパレータを突き破ってリーク不
良が多発する。そのため、焼結型正極板作製後の放置環
境および電池構成の作業環境を低湿度に保持したり、放
置時間および作業時間を短縮したりするなど、様々な対
策が講じられているものの、抜本解決には至っていな
い。As described above, in the conventional sintered positive electrode plate for a nickel-metal hydride battery, nickel hydroxide abnormally precipitates due to moisture absorption during standing and breaks through the separator, resulting in frequent leak failure. For this reason, various measures have been taken, such as maintaining the storage environment after the production of the sintered positive electrode plate and the working environment of the battery configuration at low humidity, and shortening the storage time and working time. Has not been reached.
【０００６】[0006]
【発明が解決しようとする課題】本発明は、上記従来の
課題を解決するためのもので、放置時の吸湿による水酸
化ニッケルの異常析出がなく、放置環境や放置期間など
に関する制約を必要としないニッケル水素電池用焼結型
正極板および前記正極板を備えたニッケル水素電池を提
供することを目的とする。また本発明は、リーク不良の
起こりにくいニッケル水素電池を与える焼結型正極板と
その製造方法および前記正極板を備えたニッケル水素電
池を提供することを目的とする。SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and does not cause abnormal precipitation of nickel hydroxide due to moisture absorption during standing, and requires restrictions on the standing environment and the standing period. It is an object of the present invention to provide a sintered positive electrode plate for a nickel metal hydride battery and a nickel metal hydride battery provided with the positive electrode plate. It is another object of the present invention to provide a sintered positive electrode plate that provides a nickel-metal hydride battery that is unlikely to cause a leak failure, a method of manufacturing the same, and a nickel-metal hydride battery including the positive electrode plate.
【０００７】[0007]
【課題を解決するための手段】上記目的を達成するた
め、本発明のニッケル水素電池用焼結型正極板は、ニッ
ケルめっき鋼板製芯材を含むニッケル焼結体からなる多
孔性基板、および前記多孔性基板に充填された、ジルコ
ニウム、ランタンおよびスカンジウムの群より選択され
た少なくとも１種の化合物を添加物として含むニッケル
の水酸化物を主成分とする活物質からなることを特徴と
する。In order to achieve the above object, a sintered positive electrode plate for a nickel-metal hydride battery according to the present invention comprises: a porous substrate made of a nickel sintered body including a core material made of a nickel-plated steel sheet; The porous substrate is made of an active material mainly composed of nickel hydroxide containing as an additive at least one compound selected from the group consisting of zirconium, lanthanum and scandium.
【０００８】前記ニッケル水素電池用焼結型正極板にお
いては、ジルコニウム、ランタンおよびスカンジウムの
群より選択された少なくとも１種の添加物の重量が、前
記活物質の重量に対して０．１重量％以上１０重量％以
下であることが好ましい。またニッケル水素電池用焼結
型正極板においては、前記ニッケルの水酸化物が、ニッ
ケルの原子価が２を越える高次化合物であることが好ま
しい。In the sintered positive electrode plate for a nickel-metal hydride battery, the weight of at least one additive selected from the group consisting of zirconium, lanthanum and scandium is 0.1% by weight based on the weight of the active material. It is preferably at least 10% by weight. In the sintered positive electrode plate for a nickel-metal hydride battery, it is preferable that the nickel hydroxide is a high-order compound in which the valence of nickel exceeds 2.
【０００９】次に本発明のニッケル水素電池用焼結型正
極板の第１番目の製造方法は、ニッケルめっき鋼板製芯
材を含むニッケル焼結体からなる多孔性基板に、ニッケ
ルの水酸化物からなる活物質を充填する工程、ジルコニ
ウム、ランタンおよびスカンジウムの群より選択された
少なくとも１種の硝酸塩、硫酸塩、もしくは塩化物を所
定量含む水溶液に含浸した後、水酸化ナトリウム水溶液
に浸漬する工程、および化成処理する工程を含むことを
特徴とする。Next, a first method for producing a sintered positive electrode plate for a nickel-metal hydride battery according to the present invention comprises the steps of: providing a porous substrate made of a nickel sintered body including a core material made of nickel-plated steel sheet; Filling with an aqueous solution containing a predetermined amount of at least one nitrate, sulfate or chloride selected from the group consisting of zirconium, lanthanum and scandium, and then immersing in an aqueous sodium hydroxide solution And a step of performing a chemical conversion treatment.
【００１０】次に本発明のニッケル水素電池用焼結型正
極板の第２番目の製造方法は、ニッケルめっき鋼板製芯
材を含むニッケル焼結体からなる多孔性基板を、ジルコ
ニウム、ランタンおよびスカンジウムの群より選択され
た少なくとも１種の硝酸塩、硫酸塩、もしくは塩化物を
所定量含むニッケル塩水溶液に含浸した後、水酸化ナト
リウム水溶液に浸漬してニッケルの水酸化物を主成分と
する活物質を充填する工程、および化成処理する工程を
含むことを特徴とする。Next, a second method for producing a sintered positive electrode plate for a nickel-metal hydride battery according to the present invention is a method for preparing a porous substrate made of a nickel sintered body including a core material made of a nickel-plated steel sheet by using zirconium, lanthanum and scandium. An active material containing nickel hydroxide as a main component by impregnating with a nickel salt aqueous solution containing a predetermined amount of at least one nitrate, sulfate, or chloride selected from the group of And a step of performing a chemical conversion treatment.
【００１１】本発明は、また上記の焼結型正極板を備え
たニッケル水素電池を提供する。本発明によれば、放置
時の吸湿による水酸化ニッケルの異常析出がなく、放置
環境や放置期間などに関する制約を必要としないニッケ
ル水素電池用焼結型正極板が得られる。また、この焼結
型正極板を用いることにより、リーク不良の起こりにく
いニッケル水素電池を提供することができる。The present invention also provides a nickel-metal hydride battery provided with the above sintered positive electrode plate. According to the present invention, it is possible to obtain a sintered positive electrode plate for a nickel-metal hydride battery that does not cause abnormal precipitation of nickel hydroxide due to moisture absorption during standing and does not require restrictions on the standing environment and the standing period. Further, by using this sintered positive electrode plate, a nickel-metal hydride battery in which a leak failure does not easily occur can be provided.
【００１２】[0012]
【発明の実施の形態】本発明によるニッケル水素電池用
焼結型正極板では、局部アノードとなる鉄の溶解反応が
起こり、鉄と水酸イオンによる錯体が形成されて鉄露出
部の近傍の液相が酸性になっても、添加した金属水酸化
物が溶解することによってその酸性を中和して焼結体を
構成するニッケルの溶解が抑制される。すなわち、ここ
で用いることができる添加物としては、酸に溶解しやす
くかつ塩基性の強い金属水酸化物が好ましい。このよう
なｐＨ緩衝作用のある添加物として、例えばジルコニウ
ム、ランタン、スカンジウムなどの水酸化物や酸化物が
あげられる。上記のような理由により、放置時の吸湿に
よる水酸化ニッケルの異常析出はなくなり、放置環境や
放置期間などに関する制約は不要になる。本発明は、特
に個片に切断する前の化成処理により、ニッケルの水酸
化物をニッケルの原子価が２を越える高次化合物に変換
した正極板に有効である。高次のニッケル水酸化物は、
鉄との局部電池を形成しやすいのである。本発明による
焼結型正極板を用いたニッケル水素電池は、水酸化ニッ
ケルの異常析出が無くなるためセパレータを突き破るよ
うなリーク不良が発生しにくい。BEST MODE FOR CARRYING OUT THE INVENTION In the sintered positive electrode plate for a nickel-metal hydride battery according to the present invention, a dissolution reaction of iron serving as a local anode takes place, and a complex is formed by iron and hydroxide ions to form a liquid near the exposed iron portion. Even if the phase becomes acidic, the added metal hydroxide dissolves to neutralize the acidity and suppress the dissolution of nickel constituting the sintered body. That is, as the additive that can be used here, a metal hydroxide that is easily dissolved in an acid and has a strong basicity is preferable. Such additives having a pH buffering action include, for example, hydroxides and oxides such as zirconium, lanthanum, and scandium. For the reasons described above, abnormal precipitation of nickel hydroxide due to moisture absorption during leaving is eliminated, and restrictions on the leaving environment, the leaving period, and the like become unnecessary. The present invention is particularly effective for a positive electrode plate in which nickel hydroxide is converted into a higher-order compound having a valence of more than 2 by a chemical conversion treatment before cutting into individual pieces. Higher order nickel hydroxide is
It is easy to form a local battery with iron. In the nickel-metal hydride battery using the sintered positive electrode plate according to the present invention, since the abnormal precipitation of nickel hydroxide is eliminated, a leak failure such as breaking through the separator hardly occurs.
【００１３】[0013]
【実施例】（実施例１）まず、連続めっき装置を用い
て、幅約６００ｍｍ、長さ約５００ｍ、厚さ約８０μｍ
の穿孔鋼板に、厚さ約１０μｍのニッケルめっきを施し
た。このニッケルめっき鋼板に、カーボニルニッケル粉
末とメチルセルローズと水とからなるスラリーを塗布
し、１００℃で乾燥した後、水素を含む還元雰囲気中に
おいて約１０００℃で熱処理し、多孔性焼結基板を作製
した。この多孔性基板のニッケル焼結体層の厚さは、片
面につき約３００μｍであり、約８０％の多孔度を有し
ていた。次に、この多孔性基板に活物質を充填した。多
孔性基板を８０℃に保持された、４．５Ｍの硝酸ニッケ
ルと０．１Ｍの硝酸コバルトとの混合水溶液に３分間浸
漬し、８０℃で９０分間乾燥させた後、８０℃、６．５
Ｍの水酸化ナトリウム水溶液に浸漬する操作を１０回繰
り返すことにより行った。次に６０℃、２Ｍの硝酸ジル
コニウム水溶液に浸漬してから乾燥し、８０℃、６．５
Ｍの水酸化ナトリウム水溶液に浸漬することにより水酸
化ジルコニウムを添加した。次に化成処理として、電解
液に８０℃、６．５Ｍの水酸化ナトリウム水溶液を用い
て、充放電を２回繰り返して行った。なお、化成電流レ
ートは、充電および放電ともに１Ｃとし、ガス発生電位
に達するまで通電した。このような条件で化成処理をし
た結果、活物質の外観が緑色から黒色に変化し、活物質
が２価よりも高次のニッケルの水酸化物に置換されたこ
とが確認された。なお、上記のニッケルめっき処理から
化成処理までの一連の工程は、量産性の観点からロール
トゥーロールの連続処理で行った。次に、ロールトゥー
ロールの連続処理で活物質の充填および化成処理した多
孔性基板を、スリット切断することにより、単セルサイ
ズに個片化し、ニッケル水素電池用焼結型正極板を作製
した。作製した焼結型正極板の形状は、４５ｍｍ×５４
０ｍｍの短冊型で、４辺の端面すべてがスリット切断面
となるように加工した。上記の処理の中で硝酸ジルコニ
ウム水溶液の濃度を変えたり、処理回数を変えることで
活物質の重量に対する水酸化ジルコニウムの添加量を変
えることができる。また、硝酸ジルコニウムに替えて硝
酸ランタンや硝酸スカンジウムを用いて、極板に水酸化
ランタンや水酸化スカンジウムを添加し、同様の処理を
行った極板も作成した。これらの極板においてそれぞれ
添加量を変えた焼結型正極板を作製し、放置試験を行う
ことにより、水酸化ニッケルの極板表面への異常析出の
発生頻度を測定した。放置試験には、各水準とも、１０
０個の焼結型正極板をサンプルとして投入し、一定放置
条件で、２００時間放置後に、サンプルの外観を観察し
た。外観観察の結果から、水酸化ニッケルの異常析出が
発生したサンプル数を確認し、異常析出の発生頻度
（％）とした。なお、放置条件は、温度：４０℃、相対
湿度：３０％、温度：４０℃、相対湿度６０％、および
温度：４０℃、相対湿度９０％の３水準とした。表１は
放置試験の結果を示している。(Example 1) First, using a continuous plating apparatus, a width of about 600 mm, a length of about 500 m, and a thickness of about 80 μm.
Was subjected to nickel plating with a thickness of about 10 μm. A slurry composed of carbonyl nickel powder, methyl cellulose and water is applied to this nickel-plated steel sheet, dried at 100 ° C., and then heat-treated at about 1000 ° C. in a reducing atmosphere containing hydrogen to produce a porous sintered substrate. did. The thickness of the nickel sintered body layer of this porous substrate was about 300 μm per side, and had a porosity of about 80%. Next, the porous substrate was filled with an active material. The porous substrate was immersed in a mixed aqueous solution of 4.5 M nickel nitrate and 0.1 M cobalt nitrate kept at 80 ° C. for 3 minutes, dried at 80 ° C. for 90 minutes, and then dried at 80 ° C. and 6.5.
The operation of immersing in M sodium hydroxide aqueous solution was repeated 10 times. Next, it is immersed in a 2M aqueous solution of zirconium nitrate at 60 ° C., dried and dried at 80 ° C. and 6.5.
Zirconium hydroxide was added by immersion in an M aqueous sodium hydroxide solution. Next, as a chemical conversion treatment, charging and discharging were repeated twice using a 6.5 M aqueous sodium hydroxide solution at 80 ° C. as an electrolytic solution. The formation current rate was set to 1 C for both charging and discharging, and current was supplied until the gas generation potential was reached. As a result of the chemical conversion treatment under such conditions, the appearance of the active material changed from green to black, and it was confirmed that the active material was replaced with nickel hydroxide having a higher order than divalent. Note that a series of steps from the nickel plating treatment to the chemical conversion treatment was performed by a roll-to-roll continuous treatment from the viewpoint of mass productivity. Next, the porous substrate, which had been filled with the active material and subjected to a chemical conversion treatment in a continuous roll-to-roll process, was cut into slits to be singulated into single cells, thereby producing a sintered positive electrode plate for a nickel-metal hydride battery. The shape of the produced sintered positive electrode plate is 45 mm × 54
It was a rectangular strip of 0 mm and processed so that all of the four end faces became slit cut faces. The amount of zirconium hydroxide added to the weight of the active material can be changed by changing the concentration of the zirconium nitrate aqueous solution or changing the number of times of the treatment. Further, lanthanum nitrate or scandium nitrate was used instead of zirconium nitrate, lanthanum hydroxide or scandium hydroxide was added to the electrode plate, and an electrode plate was prepared in the same manner. Sintered positive electrode plates were prepared by changing the amount of each of these electrode plates, and a standing test was performed to measure the frequency of occurrence of abnormal precipitation of nickel hydroxide on the electrode plate surface. In the standing test, each level was 10
Zero sintered positive electrode plates were put as a sample, and after standing for 200 hours under a constant standing condition, the appearance of the sample was observed. From the results of the appearance observation, the number of samples in which abnormal precipitation of nickel hydroxide occurred was confirmed, and the frequency of occurrence of abnormal precipitation (%) was determined. The leaving conditions were three levels: temperature: 40 ° C., relative humidity: 30%, temperature: 40 ° C., relative humidity: 60%, and temperature: 40 ° C., relative humidity: 90%. Table 1 shows the results of the standing test.
【００１４】[0014]
【表１】 [Table 1]
【００１５】表１に示すように、添加物を添加しない従
来のニッケル水素電池用焼結型正極板では、放置条件が
温度：４０℃、相対湿度：３０％で、異常析出の発生頻
度が２％となった。放置条件が高湿度になるにしたがっ
て、異常析出の発生頻度が高くなり、温度：４０℃、相
対湿度９０％の放置条件では、発生頻度が１００％にな
った。これに対し、水酸化ジルコニウムを０．１重量％
添加した極板での水酸化ニッケルの異常析出は、温度：
４０℃、相対湿度：９０％の放置条件でも２％までに減
り、０．５重量％以上添加した極板では確認されなかっ
た。また、水酸化ランタンを０．１重量％添加した極板
での水酸化ニッケルの異常析出は、温度：４０℃、相対
湿度：９０％の放置条件でも１％までに減り、０．５重
量％以上添加した極板では確認されなかった。同様に、
水酸化スカンジウムを０．１重量％添加した極板での水
酸化ニッケルの異常析出は、温度：４０℃、相対湿度：
９０％の放置条件でも２％までに減り、０．５重量％以
上添加した極板では確認されなかった。これらの添加物
は、あまり多く添加すると電池容量が減ることになり、
また多く添加するために硝酸ジルコニウム、硝酸ランタ
ン、硝酸スカンジウムの水溶液濃度を上げたり、処理回
数を増やすと表面に付着して電池特性が悪化する。添加
量としては活物質に対して１０重量％以下にすること
が、電池特性やコスト面からも好ましい。上記実施例に
おいて、添加物は単独で用いたが混合溶液を用いれば２
種類以上の添加物を添加することもでき、同様の効果が
得られる。また、添加のためにジルコニウム、ランタ
ン、スカンジウムの硝酸塩を用いたが、硫酸塩や塩化物
の水溶液を用いることもできる。As shown in Table 1, in the conventional sintered positive electrode plate for a nickel-metal hydride battery to which no additive was added, the leaving conditions were a temperature of 40 ° C., a relative humidity of 30%, and a frequency of abnormal precipitation of 2%. %. The frequency of occurrence of abnormal precipitation increased as the storage conditions increased, and the frequency of occurrence increased to 100% under the storage conditions of a temperature of 40 ° C. and a relative humidity of 90%. On the other hand, 0.1% by weight of zirconium hydroxide was used.
Abnormal precipitation of nickel hydroxide on the added electrode plate is caused by the temperature:
Even when left at 40 ° C. and a relative humidity of 90%, it was reduced to 2%, and was not confirmed in the electrode plate added with 0.5% by weight or more. The abnormal precipitation of nickel hydroxide on the electrode plate to which 0.1% by weight of lanthanum hydroxide was added was reduced to 1% even when left at a temperature of 40 ° C. and a relative humidity of 90%. It was not confirmed in the electrode plate added above. Similarly,
Abnormal precipitation of nickel hydroxide on an electrode plate containing 0.1% by weight of scandium hydroxide was caused by a temperature of 40 ° C and a relative humidity of:
Even under the condition of 90% standing, it decreased to 2%, and was not confirmed in the electrode plate to which 0.5% by weight or more was added. Adding too much of these additives will reduce battery capacity,
In addition, when a large amount of zirconium nitrate, lanthanum nitrate, or scandium nitrate is added to increase the concentration of the aqueous solution or the number of treatments is increased, the battery adheres to the surface and battery characteristics deteriorate. The addition amount is preferably 10% by weight or less based on the active material in view of battery characteristics and cost. In the above example, the additive was used alone, but if a mixed solution was used, 2
More than two or more kinds of additives can be added, and the same effect can be obtained. Although nitrates of zirconium, lanthanum and scandium are used for the addition, aqueous solutions of sulfates and chlorides can also be used.
【００１６】（実施例２）実施例１と同様に作製した多
孔性基板に活物質を充填した。多孔性基板を８０℃に保
持された、４．５Ｍの硝酸ニッケル、０．１Ｍの硝酸コ
バルトおよび０．５Ｍの硝酸ジルコニウムの混合水溶液
に３分間浸漬し、８０℃で９０分間乾燥させた後、８０
℃、６．５Ｍの水酸化ナトリウム水溶液に浸漬する操作
を１０回繰り返すことにより行った。次に化成処理とし
て、電解液に８０℃、６．５Ｍの水酸化ナトリウム水溶
液を用いて、充放電を２回繰り返して行った。なお、化
成電流レートは、充電および放電ともに１Ｃとし、ガス
発生電位に達するまで通電した。このような条件で化成
処理をした結果、活物質の外観が緑色から黒色に変化
し、活物質が２価よりも高次のニッケルの水酸化物に置
換されたことが確認された。上記のニッケルめっき処理
から化成処理までの一連の工程は、量産性の観点からロ
ールトゥーロールの連続処理で行った。次に、ロールト
ゥーロールの連続処理で活物質の充填および化成処理し
た多孔性基板を、スリット切断することにより、単セル
サイズに個片化し、ニッケル水素電池用焼結型正極板を
作製した。作製した焼結型正極板の形状は、４５ｍｍ×
５４０ｍｍの短冊型で、４辺の端面すべてがスリット切
断面となるように加工した。上記の活物質充填処理の中
で混合溶液中の硝酸ジルコニウムの濃度を変えること
で、活物質の重量に対する水酸化ジルコニウムの添加量
を変えることができる。また、混合溶液中の硝酸ジルコ
ニウムに替えて硝酸ランタンや硝酸スカンジウムを用い
て、極板に水酸化ランタンや硝酸スカンジウムを添加
し、同様の処理を行った極板も作成した。これらの極板
においてそれぞれ添加量を変えた焼結型正極板を作製
し、放置試験を行うことにより、水酸化ニッケルの極板
表面への異常析出の発生頻度を測定した。放置試験に
は、各水準とも、１００個の焼結型正極板をサンプルと
して投入し、一定放置条件で、２００時間放置後に、サ
ンプルの外観を観察した。外観観察の結果から、水酸化
ニッケルの異常析出が発生したサンプル数を確認し、異
常析出の発生頻度（％）とした。なお、放置条件は実施
例１と同様に温度：４０℃、相対湿度：３０％、温度：
４０℃、相対湿度：６０％、および温度：４０℃、相対
湿度：９０％の３水準とした。表２は放置試験の結果を
示している。Example 2 An active material was filled in a porous substrate manufactured in the same manner as in Example 1. The porous substrate was immersed in a mixed aqueous solution of 4.5 M nickel nitrate, 0.1 M cobalt nitrate and 0.5 M zirconium nitrate held at 80 ° C. for 3 minutes, and dried at 80 ° C. for 90 minutes. 80
The operation of immersing in a 6.5 M sodium hydroxide aqueous solution at 6.5 ° C. was repeated 10 times. Next, as a chemical conversion treatment, charging and discharging were repeated twice using a 6.5 M aqueous sodium hydroxide solution at 80 ° C. as an electrolytic solution. The formation current rate was set to 1 C for both charging and discharging, and current was supplied until the gas generation potential was reached. As a result of the chemical conversion treatment under such conditions, the appearance of the active material changed from green to black, and it was confirmed that the active material was replaced with nickel hydroxide having a higher order than divalent. A series of steps from the nickel plating treatment to the chemical conversion treatment was performed by a roll-to-roll continuous treatment from the viewpoint of mass productivity. Next, the porous substrate, which had been filled with the active material and subjected to a chemical conversion treatment in a continuous roll-to-roll process, was cut into slits to be singulated into single cells, thereby producing a sintered positive electrode plate for a nickel-metal hydride battery. The shape of the produced sintered positive electrode plate is 45 mm x
It was a 540 mm strip, and was processed so that all of the four end faces were slit cut faces. By changing the concentration of zirconium nitrate in the mixed solution during the above-mentioned active material filling treatment, the amount of zirconium hydroxide added to the weight of the active material can be changed. Further, lanthanum nitrate or scandium nitrate was used instead of zirconium nitrate in the mixed solution, and lanthanum hydroxide or scandium nitrate was added to the electrode plate, and an electrode plate was prepared in the same manner. Sintered positive electrode plates were prepared by changing the amount of each of these electrode plates, and a standing test was performed to measure the frequency of occurrence of abnormal precipitation of nickel hydroxide on the electrode plate surface. In each of the standing tests, 100 sintered positive electrode plates were charged as samples for each level, and after standing for 200 hours under constant leaving conditions, the appearance of the samples was observed. From the results of the appearance observation, the number of samples in which abnormal precipitation of nickel hydroxide occurred was confirmed, and the frequency of occurrence of abnormal precipitation (%) was determined. In addition, the leaving conditions were the same as in Example 1, temperature: 40 ° C., relative humidity: 30%, temperature:
There were three levels: 40 ° C., relative humidity: 60%, and temperature: 40 ° C., relative humidity: 90%. Table 2 shows the results of the standing test.
【００１７】[0017]
【表２】 [Table 2]
【００１８】表２に示すように、添加物を添加しない従
来のニッケル水素電池用焼結型正極板では、実施例１と
同様に放置条件が高湿度になるにしたがって、異常析出
の発生頻度が高くなり、温度：４０℃、相対湿度：９０
％の放置条件では、発生頻度が１００％になった。これ
に対し、水酸化ジルコニウムを０．１重量％添加した極
板での水酸化ニッケルの異常析出は、温度：４０℃、相
対湿度：９０％の放置条件でも１％までに減り、０．５
重量％以上添加した極板では確認されなかった。また、
水酸化ランタンを０．１重量％添加した極板での水酸化
ニッケルの異常析出は、温度：４０℃、相対湿度：９０
％の放置条件でも１％までに減り、０．５重量％以上添
加した極板では確認されなかった。同様に、水酸化スカ
ンジウムを０．１重量％添加した極板での水酸化ニッケ
ルの異常析出は、温度：４０℃、相対湿度：９０％の放
置条件でも１％までに減り、０．５重量％以上添加した
極板では確認されなかった。これらの添加物は、あまり
多く添加すると電池容量などの電池特性が悪化する。活
物質に対して１０重量％以下にすることが、電池特性や
コスト面からも好ましい。上記実施例において、含浸液
として４．５Ｍの硝酸ニッケル、０．１Ｍの硝酸コバル
トおよび０．５Ｍの硝酸ジルコニウムの混合水溶液を用
いたが、ジルコニウム、ランタン、スカンジウムの中で
２種類以上の硝酸塩を混合溶液に加えることにより、２
種類以上の添加物を同時に添加することもでき、同様の
効果が得られる。また、混合溶液の添加物としてジルコ
ニウム、ランタン、スカンジウムの硝酸塩を用いたが、
硫酸塩や塩化物を用いることもでき、硝酸ニッケル、硝
酸コバルトに関しても硫酸塩や塩化物を用いることがで
きる。As shown in Table 2, in the conventional sintered positive electrode plate for a nickel-metal hydride battery to which no additive was added, the frequency of occurrence of abnormal deposition increased as the storage condition increased as in Example 1. High, temperature: 40 ° C, relative humidity: 90
%, The frequency of occurrence was 100%. On the other hand, the abnormal precipitation of nickel hydroxide on the electrode plate to which 0.1% by weight of zirconium hydroxide was added was reduced to 1% even when left at a temperature of 40 ° C. and a relative humidity of 90%.
It was not confirmed in the electrode plate to which the weight% or more was added. Also,
Abnormal precipitation of nickel hydroxide on an electrode plate to which 0.1% by weight of lanthanum hydroxide was added was carried out at a temperature of 40 ° C. and a relative humidity of 90%.
%, It decreased to 1% even under the condition of standing, and was not confirmed in the electrode plate to which 0.5% by weight or more was added. Similarly, abnormal precipitation of nickel hydroxide on an electrode plate to which scandium hydroxide was added at 0.1% by weight was reduced to 1% even when left at a temperature of 40 ° C. and a relative humidity of 90%. % Or more was not confirmed. If these additives are added in too large amounts, battery characteristics such as battery capacity deteriorate. It is preferable that the content be 10% by weight or less based on the active material from the viewpoint of battery characteristics and cost. In the above embodiment, a mixed aqueous solution of 4.5 M nickel nitrate, 0.1 M cobalt nitrate, and 0.5 M zirconium nitrate was used as the impregnating liquid, but two or more nitrates among zirconium, lanthanum, and scandium were used. By adding to the mixed solution, 2
More than one type of additive can be added simultaneously, and the same effect can be obtained. In addition, zirconium, lanthanum, and scandium nitrate were used as additives in the mixed solution.
Sulfates and chlorides can be used, and sulfates and chlorides can also be used for nickel nitrate and cobalt nitrate.
【００１９】（実施例３）実施例１〜２で作製した本発
明のニッケル水素電池用焼結型正極板および添加物を添
加していない従来のニッケル水素電池用焼結型正極板を
用いて、それぞれニッケル水素電池を作製した。同一条
件で作製した水素吸蔵合金（ＭｍＮｉ3.55Ｍｎ0.4Ａｌ
0.3Ｃｏ0.75）からなる負極を、ポリプロピレン不織布
からなるセパレータを介して、正極板と共に巻き、缶ケ
ースに入れた状態で、温度：４０℃、相対湿度：７０％
の条件下で２４時間放置した。次に、水酸化カリウム水
溶液からなる電解液を封入して、ニッケル水素電池を各
１００個作製した。作製した各ニッケル水素電池のリー
ク不良を測定した結果、従来のニッケル水素電池用焼結
型正極板を用いたニッケル水素電池では、リーク不良が
８％発生した。これに対し、水酸化ジルコニウム、水酸
化ランタン、もしくは水酸化スカンジウムを０．１重量
％以上添加した本発明のニッケル水素電池用焼結型正極
板を用いたニッケル水素電池では、リーク不良がまった
く発生しなかった。なお、不良発生したニッケル水素電
池の不良解析を行った結果、正極板から異常析出した水
酸化ニッケルが原因であることが明らかになった。上記
のように、本発明のニッケル水素電池用焼結型正極板を
用いることにより、水酸化ニッケルの異常析出が抑制さ
れ、リーク不良の起こりにくいニッケル水素電池を実現
することができた。Example 3 Using the sintered positive electrode plate for a nickel-metal hydride battery of the present invention prepared in Examples 1 and 2 and a conventional sintered positive electrode plate for a nickel-metal hydride battery to which no additive was added. Then, nickel-metal hydride batteries were manufactured. Hydrogen storage alloy (MmNi 3.55 Mn 0.4 Al manufactured under the same conditions
A negative electrode made of 0.3 Co 0.75 ) is wound together with a positive electrode plate through a separator made of a nonwoven polypropylene fabric, and placed in a can case at a temperature of 40 ° C. and a relative humidity of 70%.
For 24 hours. Next, an electrolytic solution composed of an aqueous solution of potassium hydroxide was sealed, and 100 nickel-metal hydride batteries were produced. As a result of measuring the leak failure of each manufactured nickel-metal hydride battery, 8% of the leak failure occurred in the nickel-metal hydride battery using the conventional sintered positive electrode plate for the nickel-metal hydride battery. On the other hand, in the nickel-metal hydride battery using the sintered positive electrode plate for the nickel-metal hydride battery of the present invention to which zirconium hydroxide, lanthanum hydroxide, or scandium hydroxide is added in an amount of 0.1% by weight or more, no leak failure occurs. Did not. In addition, as a result of analyzing the failure of the nickel-metal hydride battery in which the failure occurred, it was found that the cause was nickel hydroxide abnormally precipitated from the positive electrode plate. As described above, by using the sintered positive electrode plate for a nickel-metal hydride battery of the present invention, abnormal precipitation of nickel hydroxide was suppressed, and a nickel-hydrogen battery with less leak failure was realized.
【００２０】[0020]
【発明の効果】以上のように本発明によれば、ニッケル
めっき鋼板製芯材を含むニッケル焼結体からなる多孔性
基板、および前記多孔性基板に充填された、ジルコニウ
ム、ランタンおよびスカンジウムの群より選択された少
なくとも１種の化合物を添加物として含むニッケルの水
酸化物を主成分とする活物質を用いることにより、その
ｐＨ緩衝作用により水酸化ニッケルの異常析出をなくす
ことができる。また、放置時の吸湿による水酸化ニッケ
ルの異常析出がなく、放置環境や放置期間などに関する
制約が不要なニッケル水素電池用焼結型正極板を提供す
ることができる。従って、本発明によれば、水酸化ニッ
ケルの異常析出が要因となるリーク不良が起こりにくい
ニッケル水素電池が得られる。As described above, according to the present invention, a porous substrate made of a nickel sintered body including a core material made of a nickel-plated steel plate, and a group of zirconium, lanthanum and scandium filled in the porous substrate. By using an active material mainly composed of nickel hydroxide containing at least one compound selected as an additive, abnormal precipitation of nickel hydroxide can be eliminated by its pH buffering action. In addition, it is possible to provide a sintered positive electrode plate for a nickel-metal hydride battery that does not cause abnormal precipitation of nickel hydroxide due to moisture absorption during standing and does not require restrictions on the standing environment and the standing period. Therefore, according to the present invention, it is possible to obtain a nickel-metal hydride battery in which a leak failure caused by abnormal precipitation of nickel hydroxide is unlikely to occur.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 丸田 雅義 大阪府門真市大字門真1006番地 松下電器 産業株式会社内 (72)発明者 棚橋 正和 大阪府門真市大字門真1006番地 松下電器 産業株式会社内 (72)発明者 井垣 恵美子 大阪府門真市大字門真1006番地 松下電器 産業株式会社内 (72)発明者 村上 義樹 大阪府門真市大字門真1006番地 松下電器 産業株式会社内 (72)発明者 貝田 理 大阪府門真市大字門真1006番地 松下電器 産業株式会社内 Ｆターム(参考） 5H016 AA06 BB09 BB10 BB14 CC03 EE01 EE05 HH01 5H017 AA02 AS02 BB04 BB08 BB13 BB16 CC27 EE04 HH01 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masayoshi Maruta 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. 72) Inventor Emiko Igaki 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture, Japan Matsushita Electric Industrial Co., Ltd. 1006 Kadoma Kadoma Matsushita Electric Industrial Co., Ltd. F-term (reference) 5H016 AA06 BB09 BB10 BB14 CC03 EE01 EE05 HH01 5H017 AA02 AS02 BB04 BB08 BB13 BB16 CC27 EE04 HH01
Claims (6)
ル焼結体からなる多孔性基板、および前記多孔性基板に
充填された、ジルコニウム、ランタンおよびスカンジウ
ムの群より選択された少なくとも１種の化合物を添加物
として含むニッケルの水酸化物を主成分とする活物質か
らなることを特徴とするニッケル水素電池用焼結型正極
板。1. A porous substrate made of a nickel sintered body including a core material made of a nickel-plated steel sheet, and at least one compound selected from the group consisting of zirconium, lanthanum and scandium filled in the porous substrate. A sintered positive electrode plate for a nickel-metal hydride battery, comprising an active material containing a nickel hydroxide as an additive as a main component.
ンジウムの群より選択された少なくとも１種の添加物の
重量が、前記活物質の重量に対して０．１重量％以上１
０重量％以下であることを特徴とする請求項１記載のニ
ッケル水素電池用焼結型正極板。2. The weight of at least one additive selected from the group consisting of zirconium, lanthanum and scandium is at least 0.1% by weight based on the weight of the active material.
The sintered positive electrode plate for a nickel-metal hydride battery according to claim 1, wherein the content is 0% by weight or less.
原子価が２を越える高次化合物である請求項１記載のニ
ッケル水素電池用焼結型正極板。3. The sintered positive electrode plate for a nickel-metal hydride battery according to claim 1, wherein the nickel hydroxide is a higher-order compound having a valence of nickel of more than 2.
ル焼結体からなる多孔性基板に、ニッケルの水酸化物か
らなる活物質を充填する工程、ジルコニウム、ランタン
およびスカンジウムの群より選択された少なくとも１種
の硝酸塩、硫酸塩、もしくは塩化物を所定量含む水溶液
に含浸した後、水酸化ナトリウム水溶液に浸漬する工
程、および化成処理する工程を含むことを特徴とするニ
ッケル水素電池用焼結型正極板の製造方法。4. A step of filling a porous substrate made of a nickel sintered body containing a core material made of a nickel-plated steel sheet with an active material made of nickel hydroxide, at least one selected from the group consisting of zirconium, lanthanum and scandium. A sintered positive electrode for a nickel-metal hydride battery, comprising: a step of impregnating an aqueous solution containing a predetermined amount of one kind of nitrate, sulfate, or chloride, followed by a step of immersion in an aqueous solution of sodium hydroxide, and a step of chemical conversion treatment. Plate manufacturing method.
ル焼結体からなる多孔性基板を、ジルコニウム、ランタ
ンおよびスカンジウムの群より選択された少なくとも１
種の硝酸塩、硫酸塩、もしくは塩化物を所定量含むニッ
ケル塩水溶液に含浸した後、水酸化ナトリウム水溶液に
浸漬してニッケルの水酸化物を主成分とする活物質を充
填する工程、および化成処理する工程を含むことを特徴
とするニッケル水素電池用焼結型正極板の製造方法。5. A porous substrate made of a nickel sintered body including a core material made of a nickel-plated steel sheet, wherein at least one selected from the group consisting of zirconium, lanthanum and scandium.
A step of impregnating with an aqueous solution of nickel salt containing a predetermined amount of a kind of nitrate, sulfate or chloride, and then immersing in an aqueous solution of sodium hydroxide to fill an active material mainly composed of nickel hydroxide, and a chemical conversion treatment A method for producing a sintered positive electrode plate for a nickel-metal hydride battery, the method comprising:
を備えたニッケル水素電池。6. A nickel-metal hydride battery provided with the positive electrode plate according to claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11117854A JP2000311680A (en) | 1999-04-26 | 1999-04-26 | Sintered type positive electrode plate for nickel- hydrogen battery, its manufacture and nickel-hydrogen battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11117854A JP2000311680A (en) | 1999-04-26 | 1999-04-26 | Sintered type positive electrode plate for nickel- hydrogen battery, its manufacture and nickel-hydrogen battery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000311680A true JP2000311680A (en) | 2000-11-07 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11117854A Pending JP2000311680A (en) | 1999-04-26 | 1999-04-26 | Sintered type positive electrode plate for nickel- hydrogen battery, its manufacture and nickel-hydrogen battery |
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| Country | Link |
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| JP (1) | JP2000311680A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6452784B2 (en) | 2000-05-31 | 2002-09-17 | Matsushita Electric Industrial Co., Ltd. | Aluminum electrolytic capacitor and method for producing the same |
| US6507480B2 (en) | 2001-02-26 | 2003-01-14 | Matsushita Electric Industrial Co., Ltd. | Electric double layer capacitor |
| WO2003029619A1 (en) | 2001-09-28 | 2003-04-10 | Honda Giken Kogyo Kabushiki Kaisha | Temperature control device of evaporator |
| JP2007265631A (en) * | 2006-03-27 | 2007-10-11 | Sanyo Electric Co Ltd | Alkaline battery and manufacturing method of cathode used for it |
| JP2013004579A (en) * | 2011-06-13 | 2013-01-07 | Taiyo Yuden Co Ltd | Electrochemical capacitor |
-
1999
- 1999-04-26 JP JP11117854A patent/JP2000311680A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6452784B2 (en) | 2000-05-31 | 2002-09-17 | Matsushita Electric Industrial Co., Ltd. | Aluminum electrolytic capacitor and method for producing the same |
| US6507480B2 (en) | 2001-02-26 | 2003-01-14 | Matsushita Electric Industrial Co., Ltd. | Electric double layer capacitor |
| CN100338701C (en) * | 2001-02-26 | 2007-09-19 | 松下电器产业株式会社 | Double-layer capacitor |
| WO2003029619A1 (en) | 2001-09-28 | 2003-04-10 | Honda Giken Kogyo Kabushiki Kaisha | Temperature control device of evaporator |
| JP2007265631A (en) * | 2006-03-27 | 2007-10-11 | Sanyo Electric Co Ltd | Alkaline battery and manufacturing method of cathode used for it |
| JP2013004579A (en) * | 2011-06-13 | 2013-01-07 | Taiyo Yuden Co Ltd | Electrochemical capacitor |
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