JP3268015B2 - Hydrogen storage alloy and hydrogen storage alloy electrode - Google Patents
Hydrogen storage alloy and hydrogen storage alloy electrodeInfo
- Publication number
- JP3268015B2 JP3268015B2 JP20150892A JP20150892A JP3268015B2 JP 3268015 B2 JP3268015 B2 JP 3268015B2 JP 20150892 A JP20150892 A JP 20150892A JP 20150892 A JP20150892 A JP 20150892A JP 3268015 B2 JP3268015 B2 JP 3268015B2
- Authority
- JP
- Japan
- Prior art keywords
- hydrogen
- hydrogen storage
- storage alloy
- alloy
- electrode
- 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
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]
【産業上の利用分野】水素を吸蔵、及び、放出を行う水
素吸蔵合金と、当該水素吸蔵合金を主成分とするアルカ
リ蓄電池用水素吸蔵合金電極に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrogen storage alloy for storing and releasing hydrogen, and a hydrogen storage alloy electrode for an alkaline storage battery containing the hydrogen storage alloy as a main component.
【０００２】[0002]
【従来の技術】近年、水素を可逆的に吸蔵、放出するこ
とができる水素吸蔵合金の開発が盛んに行われている。
この水素吸蔵合金の実用例として、この水素吸蔵合金を
負極材料として用いるニッケル−水素化物アルカリ蓄電
池をあげることができる。このニッケル−水素化物アル
カリ蓄電池は従来からよく用いられる鉛蓄電池、及びニ
ッケル−カドミウム蓄電池等に比べて、軽量化を図るこ
とができ、しかも高容量化を達成することが可能になる
といった利点を有しており、今後、大変有望な電池であ
る。2. Description of the Related Art In recent years, hydrogen storage alloys capable of reversibly storing and releasing hydrogen have been actively developed.
As a practical example of the hydrogen storage alloy, a nickel-hydride alkaline storage battery using the hydrogen storage alloy as a negative electrode material can be given. This nickel-hydride alkaline storage battery has the advantages of being lighter in weight and achieving higher capacity than conventional lead storage batteries and nickel-cadmium storage batteries. It is a very promising battery in the future.
【０００３】ところで、上記した水素吸蔵合金は、アル
カリ蓄電池の材料として用いた場合、アルカリ溶液中に
存在する酸素や水酸化イオンに対する耐食性が低く、合
金の酸化が起こり、負極が劣化して、サイクル特性が低
下するという問題を有していた。この問題を解決するた
めに、従来では、水素吸蔵合金の耐食性を向上させるた
めの処理として、酸化が起こり易い金属格子の歪み部分
を直し、合金の組織を均一にするために、真空中、或い
は、不活性ガス中で熱処理をおこなっていた。When the above-mentioned hydrogen storage alloy is used as a material for an alkaline storage battery, its corrosion resistance to oxygen and hydroxide ions present in an alkaline solution is low, the alloy is oxidized, the anode is deteriorated, and the cycle is reduced. There was a problem that the characteristics deteriorated. In order to solve this problem, conventionally, as a treatment for improving the corrosion resistance of the hydrogen storage alloy, in a vacuum or in order to correct the strained portion of the metal lattice where oxidation easily occurs and to make the structure of the alloy uniform, Heat treatment in an inert gas.
【０００４】[0004]
【発明が解決しようとする課題】ところが、上記したよ
うに熱処理を行うことによって、水素吸蔵合金の耐食性
は向上するものの、水素吸蔵量が減少してしまうという
問題が生じる。即ち、このような水素吸蔵合金を負極材
料に用いた場合、負極の耐食性の向上によりサイクル特
性は上昇するものの、水素吸蔵量の減少により充放電容
量を低下させてしまうという新たな問題点が生じた。However, by performing the heat treatment as described above, the corrosion resistance of the hydrogen storage alloy is improved, but there is a problem that the hydrogen storage amount is reduced. That is, when such a hydrogen storage alloy is used as a negative electrode material, although the cycle characteristics are improved due to the improvement in the corrosion resistance of the negative electrode, a new problem arises in that the charge / discharge capacity is reduced due to a decrease in the hydrogen storage amount. Was.
【０００５】本発明は上記問題点に鑑み、耐食性が高
く、且つ、水素吸蔵量の高い水素吸蔵合金、および耐食
性が高く、且つ充放電容量の高い水素吸蔵合金電極を提
供することを目的とする。SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a hydrogen storage alloy having high corrosion resistance and high hydrogen storage capacity, and a hydrogen storage alloy electrode having high corrosion resistance and high charge and discharge capacity. .
【０００６】[0006]
【課題を解決するための手段】上記目的を達成するため
に、本発明は、水素を吸蔵、及び放出を行なうMm(希土
類金属の混合物)とNiを主体とする水素吸蔵合金におい
て、窒素を含む雰囲気中で熱処理が施されることにより
金属格子間に窒素原子が侵入されてあることを特徴とす
る。 そして、前記窒素を含む雰囲気が窒素ガス雰囲気で
あることを特徴とする。 そして、前記窒素を含む雰囲気
がアンモニアガス雰囲気であることを特徴とする。 そし
て、前記窒素を含む雰囲気が水素を同時に含むことを特
徴とする。 また、かかる水素吸蔵合金をアルカリ蓄電池
用水素吸蔵合金電極の主成分とすることを特徴とする。 [MEANS FOR SOLVING THE PROBLEMS] To achieve the above object
In addition, the present invention relates to Mm (rare earth) for absorbing and releasing hydrogen.
(Mixture of similar metals) and Ni-based hydrogen storage alloy
Heat treatment in an atmosphere containing nitrogen
Characterized by nitrogen atoms interspersed between metal lattices
You. The atmosphere containing nitrogen is a nitrogen gas atmosphere.
There is a feature. And the atmosphere containing nitrogen
Is an ammonia gas atmosphere. Soshi
Is characterized in that the atmosphere containing nitrogen simultaneously contains hydrogen.
Sign. In addition, such a hydrogen storage alloy is used in an alkaline storage battery.
As a main component of the hydrogen storage alloy electrode for use.
【０００７】[0007]
【作用】上記の水素吸蔵合金は、その金属格子間に窒素
原子が割り込んだ形で存在しており、この窒素原子が金
属格子間隔を広げるため、金属結晶構造の最小単位の体
積であるセル体積が増大する。このため、水素が金属格
子間に侵入しやすくなり水素吸蔵量が増大する。The above-mentioned hydrogen storage alloy has a form in which nitrogen atoms are interposed between metal lattices. Since the nitrogen atoms increase the metal lattice spacing, the cell volume which is the minimum unit volume of the metal crystal structure is formed. Increase. For this reason, hydrogen easily penetrates between the metal lattices, and the hydrogen storage amount increases.
【０００８】 さらに、水素吸蔵量が増加することによ
り、この水素吸蔵合金を主成分とした負極の充電容量も
増大する。加えて、窒素金属格子間に侵入させる際に、
熱処理を行うことから水素吸蔵合金の耐食性も向上す
る。ここで、窒素を金属格子間に侵入させる元素として
選んだ理由は以下のようなことからである。Further, as the hydrogen storage amount increases, the charge capacity of the negative electrode containing this hydrogen storage alloy as a main component also increases.
Increase . In addition, when penetrating between the nitrogen metal lattice,
By performing the heat treatment, the corrosion resistance of the hydrogen storage alloy is also improved. Here, the reason why nitrogen was selected as an element to penetrate into the metal lattice is as follows.
【０００９】先ず、不活性ガスの場合、反応が起こらず
金属格子間に入らないので、水素吸蔵量を向上させるこ
とは望めない。また、酸素や水素が考えられるが、酸素
の場合は、合金の酸化が起きてしまうので適さず、また
水素ガスは金属格子間に割り込むことはできても、金属
格子を効果的に押し広げるにはいたらない。First, in the case of an inert gas, a reaction does not take place and does not enter between metal lattices, so that it is not expected to improve the hydrogen storage capacity. In addition, oxygen and hydrogen are conceivable, but in the case of oxygen, oxidation of the alloy occurs, which is not suitable.In addition, even if hydrogen gas can be interrupted between metal lattices, it is necessary to effectively spread the metal lattice. I don't want to.
【００１０】さらに、他の原子番号が大きな原子は原子
の大きさが大きくなるので金属格子間に入り込むことが
できない。一方、窒素は、金属格子間に割り込むことが
でき、しかも原子の大きさも格子間隔を広げるのに適し
た大きさであった。以上のことから窒素が金属格子間に
侵入させる原子として適している。Further, other atoms having a large atomic number cannot enter into the metal lattice because the size of the atoms becomes large. On the other hand, nitrogen could be interrupted between metal lattices, and the size of atoms was suitable for widening lattice spacing. From the above, nitrogen is suitable as an atom to penetrate between metal lattices.
【００１１】[0011]
〔水素吸蔵合金〕 〔実施例１〕水素吸蔵合金粉末は以下のようにして作製
した。水素吸蔵合金の材料として、市販材料としてのミ
ッシュメタル、（Ｍｍ：希土類金属の混合物）、ニッケ
ル、コバルト、アルミニウム、及びマンガンが元素比で
１：３．１：１：０．４：０．３になるように秤量した
後これらを混合し、更にアーク溶解炉内で溶解、鋳造す
る。これにより、組成がＭｍＮｉ3.1 ＣｏＡｌ 0.4 Ｍｎ
0.3 という水素吸蔵合金鋳塊が作製される。この水素吸
蔵合金鋳塊を１０００℃で、８時間、１ａｔｍの窒素を
流しながら熱処理をおこなった。この熱処理により水素
吸蔵合金の組成は、ＭｍＮｉ3.1 ＣｏＡｌ0.4 Ｍｎ0.3
Ｎ0.5 となった。この後、室温、不活性ガス中で上記水
素吸蔵合金塊を機械的に平均粒径１５０μｍに粉砕し、
水素吸蔵合金粉末を作製した。このように作成した水素
吸蔵合金粉末を、以下（Ａ1）合金と称する。 〔実施例２〕水素吸蔵合金の熱処理をする際に、窒素ガ
ス（０．５ａｔｍ）と水素ガス（０．５ａｔｍ）との混
合ガスを流しながら熱処理をおこなった以外は、上記実
施例１と同様に水素吸蔵合金粉末を作製した。尚、この
熱処理により水素吸蔵合金の組成は、ＭｍＮｉ3.1 Ｃｏ
Ａｌ0.4 Ｍｎ0.3 Ｎ2.0 Ｈ0.1 となった。 [Hydrogen storage alloy] [Example 1] Hydrogen storage alloy powder was prepared as follows.
did. As a material for hydrogen storage alloy,
Metal, (Mm: mixture of rare earth metals), nickel
, Cobalt, aluminum, and manganese in elemental ratio
1: 3.1: 1: 0.4: 0.3
After that, they are mixed, then melted and cast in an arc melting furnace.
You. Thereby, the composition is MmNi3.1CoAl 0.4Mn
0.3Is produced. This hydrogen absorption
Zirconium ingot at 1000 ℃ for 8 hours, 1atm nitrogen
Heat treatment was performed while flowing. This heat treatment allows hydrogen
The composition of the storage alloy is MmNi3.1CoAl0.4Mn0.3
N0.5It became. Thereafter, the above water is added in an inert gas at room temperature.
Mechanically crush the elemental occlusion alloy to an average particle size of 150 μm,
A hydrogen storage alloy powder was produced. Hydrogen created in this way
The occlusion alloy powder was prepared as follows1) Called alloy. [Example 2] When heat-treating a hydrogen storage alloy, nitrogen gas
(0.5 atm) and hydrogen gas (0.5 atm)
Except that the heat treatment was performed while flowing
A hydrogen storage alloy powder was produced in the same manner as in Example 1. In addition, this
The composition of the hydrogen storage alloy is MmNi3.1Co
Al0.4Mn0.3N2.0H0.1It became.
【００１２】このように作製した水素吸蔵合金粉末を、
以下（Ａ2 ）合金と称する。 〔実施例３〕水素吸蔵合金鋳塊の熱処理を行う際に、ア
ンモニアガス（１ａｔｍ）を流しながら熱処理をおこな
った以外は、上記実施例１と同様に水素吸蔵合金粉末を
作製した。尚、この熱処理により水素吸蔵合金の組成
は、ＭｍＮｉ3.1 ＣｏＡｌ0.4Ｍｎ0.3 Ｎ1.0 となっ
た。The hydrogen storage alloy powder thus produced is
Hereinafter, it is referred to as (A 2 ) alloy. Example 3 A hydrogen-absorbing alloy powder was produced in the same manner as in Example 1 except that the heat-treatment of the hydrogen-absorbing alloy ingot was performed while flowing an ammonia gas (1 atm). The composition of the hydrogen storage alloy was changed to MmNi 3.1 CoAl 0.4 Mn 0.3 N 1.0 by this heat treatment.
【００１３】このように作製した水素吸蔵合金粉末を、
以下（Ａ3 ）合金と称する。 〔実施例４〕水素吸蔵合金鋳塊に対する熱処理の際に、
アンモニアガス（０．５ａｔｍ）と水素ガス（０．５ａ
ｔｍ）の混合ガスを流しながら、熱処理をおこなった以
外は、上記実施例１と同様に水素吸蔵合金粉末を作製し
た。尚、この熱処理により水素吸蔵合金の組成は、Ｍｍ
Ｎｉ3.1 ＣｏＡｌ0.4 Ｍｎ0.3 Ｎ3.0 Ｈ0.2 となった。[0013] The hydrogen storage alloy powder thus produced is
Hereinafter, it is referred to as (A 3 ) alloy. [Example 4] At the time of heat treatment of a hydrogen storage alloy ingot,
Ammonia gas (0.5atm) and hydrogen gas (0.5a
tm), except that the heat treatment was performed while flowing the mixed gas of tm), to prepare a hydrogen storage alloy powder in the same manner as in Example 1 above. In addition, the composition of the hydrogen storage alloy becomes Mm by this heat treatment.
Ni 3.1 CoAl 0.4 Mn 0.3 N 3.0 H 0.2 .
【００１４】このように作製した水素吸蔵合金粉末を、
以下（Ａ4 ）合金と称する。 〔比較例１〕水素吸蔵合金鋳塊に対する熱処理の際に、
水素ガス（１ａｔｍ）を流しながら熱処理をおこなった
以外は、上記実施例１と同様に水素吸蔵合金粉末を作製
した。この熱処理により水素吸蔵合金の組成は、ＭｍＮ
ｉ3.1 ＣｏＡｌ0.4 Ｍｎ0.3Ｈ0.5 となった。The hydrogen-absorbing alloy powder thus produced is
Hereinafter, it is referred to as an (A 4 ) alloy. [Comparative Example 1] At the time of heat treatment on a hydrogen storage alloy ingot,
A hydrogen storage alloy powder was prepared in the same manner as in Example 1 except that the heat treatment was performed while flowing hydrogen gas (1 atm). By this heat treatment, the composition of the hydrogen storage alloy becomes MmN
i 3.1 CoAl 0.4 Mn 0.3 H 0.5 .
【００１５】このように作製した水素吸蔵合金粉末を、
以下（Ｘ1 ）合金と称する。 〔比較例２〕水素吸蔵合金鋳塊に対する熱処理の際に、
アルゴンガス（１ａｔｍ）を流しながら行った以外は、
上記実施例１と同様に水素吸蔵合金粉末を作製した。
尚、熱処理後の水素吸蔵合金の組成は、熱処理前と同じ
である。[0015] The hydrogen storage alloy powder thus produced is
Hereinafter, it is referred to as (X 1 ) alloy. [Comparative Example 2] At the time of heat treatment on a hydrogen storage alloy ingot,
Except that it was performed while flowing argon gas (1 atm),
A hydrogen storage alloy powder was produced in the same manner as in Example 1 above.
The composition of the hydrogen storage alloy after the heat treatment is the same as before the heat treatment.
【００１６】このように作製した水素吸蔵合金粉末を、
以下（Ｘ2 ）合金と称する。 〔比較例３〕水素吸蔵合金鋳塊に対する熱処理の際に、
真空中でおこなった以外は、上記実施例１と同様に水素
吸蔵合金粉末を作製した。尚、熱処理後の水素吸蔵合金
の組成は、熱処理前と同じである。[0016] The hydrogen storage alloy powder thus produced is
Hereinafter, it is referred to as (X 2 ) alloy. [Comparative Example 3] At the time of heat treatment of a hydrogen storage alloy ingot,
A hydrogen storage alloy powder was prepared in the same manner as in Example 1 except that the process was performed in a vacuum. The composition of the hydrogen storage alloy after the heat treatment is the same as before the heat treatment.
【００１７】このように作製した水素吸蔵合金粉末を、
以下（Ｘ3 ）合金と称する。 〔比較例４〕水素吸蔵合金鋳塊に対して熱処理を施さな
い以外は上記実施例と同様に水素吸蔵合金粉末を作製し
た。このように作製した水素吸蔵合金粉末を、以下（Ｘ
4 ）合金と称する。 〔実験１〕上記の（Ａ1 ）合金〜（Ａ4 ）合金、
（Ｘ1 ）合金〜（Ｘ4 ）合金のＸ線結晶構造解析を行っ
たので、下記表１に示す。The hydrogen-absorbing alloy powder thus produced is
Hereinafter referred to as (X 3) alloy. Comparative Example 4 A hydrogen storage alloy powder was produced in the same manner as in the above example except that the heat treatment was not performed on the hydrogen storage alloy ingot. The hydrogen-absorbing alloy powder produced in this manner was designated as (X
4 ) Called alloy. [Experiment 1] The alloys (A 1 ) to (A 4 )
The X-ray crystal structure analysis of the alloys (X 1 ) to (X 4 ) is shown in Table 1 below.
【００１８】[0018]
【表１】 [Table 1]
【００１９】表１から明らかなように、本発明の処理を
行った場合、ｃ軸長には変化はないが、ａ軸長方向には
広がっており、結果的にセル体積が増大することにな
る。 〔実験２〕上記の（Ａ1 ）合金〜（Ａ4 ）合金、
（Ｘ1 ）合金〜（Ｘ4 ）合金の水素吸蔵量を測定したの
で、その結果を表１に示す。尚、表２中の結果は、水素
吸蔵量の測定結果を電気化学容量に換算したものであ
る。As is clear from Table 1, when the process of the present invention is performed, the c-axis length does not change, but the width increases in the a-axis length direction, and as a result, the cell volume increases. Become. [Experiment 2] The alloys (A 1 ) to (A 4 )
(X 1) Alloy ~ (X 4) Having determined the hydrogen storage capacity of the alloy, and the results are shown in Table 1. The results in Table 2 are obtained by converting the measurement results of the hydrogen storage amount into electrochemical capacities.
【００２０】尚、実験条件は、温度４０℃において真空
原点法によりＰＣＴ測定を行い、５ａｔｍ時の水素吸蔵
量を測定した。The experimental conditions were as follows: PCT measurement was performed at a temperature of 40 ° C. by the vacuum origin method, and the hydrogen storage amount at 5 atm was measured.
【００２１】[0021]
【表２】 [Table 2]
【００２２】表２から明らかなように、本発明の
（Ａ1 ）合金〜（Ａ4 ）合金は、比較例の（Ｘ1 ）合金
〜（Ｘ4 ）合金とくらべて、水素吸蔵量が増加してい
た。これは、金属格子間に侵入した窒素により、金属格
子間隔が広がり、水素が入りやすくなっているからであ
る。さらに、水素との混合ガスを用いると、窒素を含有
するガス単独で処理した場合よりも水素吸蔵量は増大す
る。As is apparent from Table 2, the alloys (A 1 ) to (A 4 ) of the present invention have an increased hydrogen storage capacity as compared with the alloys (X 1 ) to (X 4 ) of the comparative example. Was. This is because the nitrogen that has penetrated between the metal lattices widens the metal lattice spacing, making it easier for hydrogen to enter. Further, when a mixed gas with hydrogen is used, the amount of hydrogen occlusion increases as compared with the case where the gas containing nitrogen alone is used.
【００２３】これは、水素原子が窒素原子より金属格子
内に進入しやすいため、先ず、水素原子が金属格子内に
侵入する。窒素が既に金属格子間に侵入している水素と
入れ代わって金属格子間に侵入する。別な言い方をすれ
ば、水素が金属格子内に侵入することにより、窒素が格
子間に侵入する活性化エネルギーが低くなるからである
と言える。This is because hydrogen atoms are more likely to enter the metal lattice than nitrogen atoms, so that hydrogen atoms first enter the metal lattice. Nitrogen penetrates the metal lattice in place of hydrogen already penetrating the metal lattice. Stated another way, it can be said that hydrogen enters the metal lattice, thereby lowering the activation energy for nitrogen to enter the lattice.
【００２４】これらのことにより、窒素のみの場合に比
べて、水素が存在する方が、金属格子間に窒素が侵入し
やすくなり、水素吸蔵量が多くなったものと考えられ
る。 〔水素吸蔵合金電極〕 〔実施例１〜４〕上記本発明の（Ａ1 ）合金〜（Ａ4 ）
合金を主成分とする電極を以下のようにして作製した。From these facts, it is considered that the presence of hydrogen makes it easier for nitrogen to enter between the metal lattices and increases the amount of hydrogen occlusion as compared with the case of only nitrogen. [Hydrogen absorbing alloy electrode] [Examples 1-4] above the present invention (A 1) Alloy ~ (A 4)
An electrode containing an alloy as a main component was produced as follows.
【００２５】それぞれの水素吸蔵合金１．２ｇに対し、
導電剤であるニッケル粉末１．０ｇ、結着剤としてのＰ
ＴＦＥ０．２ｇを混合し、ペーストを作製し、プレスし
た後直径が２０ｍｍのペレットを作製した。このように
して作製したペレットを、以下それぞれ（ａ1 ）電極〜
（ａ4 ）電極と称する。 〔比較例１〜４〕電極の主成分となる水素吸蔵合金とし
て、上記比較例の（Ｘ1 ）合金〜（Ｘ4）合金を用いた
以外は、上記水素吸蔵合金電極の実施例と同様にペレッ
トを作製した。For each hydrogen storage alloy 1.2 g,
1.0 g of nickel powder as a conductive agent, and P as a binder
After mixing 0.2 g of TFE to prepare a paste and pressing, a pellet having a diameter of 20 mm was prepared. The pellets prepared in this manner are referred to as (a 1 )
(A 4 ) called an electrode. [Comparative Examples 1 to 4] Except that the (X 1 ) alloy to (X 4 ) alloy of the above comparative example were used as the hydrogen storage alloy as the main component of the electrode, the same as the above examples of the hydrogen storage alloy electrode Pellets were made.
【００２６】このように作製したペレットを、以下それ
ぞれ（ｘ1 ）電極〜（ｘ4 ）電極と称する。 〔実験１〕（ａ1 ）電極〜（ａ4 ）電極、（ｘ1 ）電極
〜（ｘ4 ）電極を用いて、電気化学容量について測定を
おこなったので、その結果を表３に示す。The pellets thus produced are hereinafter referred to as (x 1 ) electrode to (x 4 ) electrode, respectively. [Experiment 1] Electrochemical capacity was measured using electrodes (a 1 ) to (a 4 ) and electrodes (x 1 ) to (x 4 ). The results are shown in Table 3.
【００２７】尚、実験に際して、上記電極と、対極とし
て焼結式ニッケル極とを、ＫＯＨの３０％水溶液の入っ
た密閉容器内に挿入し、容器を密閉し、単電池を組み立
てた。尚、このとき、密閉容器中の圧力は５ａｔｍに設
定した。上記単電池を用い、実験条件としては、以下の
ような条件で測定を行った。５０ｍＡ／ｇで８時間充電
を行い、その後５０ｍＡ／ｇの電流で１．０Ｖになるま
で放電を行うサイクルを２回繰り返して、２回目の放電
容量を測定した。At the time of the experiment, the above-mentioned electrode and a sintered nickel electrode as a counter electrode were inserted into a closed container containing a 30% aqueous solution of KOH, the container was sealed, and a unit cell was assembled. At this time, the pressure in the closed container was set at 5 atm. The measurement was performed using the above-mentioned single cell under the following conditions. A cycle of charging at 50 mA / g for 8 hours and then discharging at a current of 50 mA / g until reaching 1.0 V was repeated twice, and the second discharge capacity was measured.
【００２８】[0028]
【表３】 [Table 3]
【００２９】表３から明らかなように、本発明の
（ａ1 ）電極〜（ａ4 ）電極を用いた場合の方が
（ｘ1 ）電極〜（ｘ4 ）電極を用いた場合と比べて、放
電容量が高いことがわかった。これにより、本発明の水
素吸蔵合金を負極材料として用いることより、放電容量
も増加したことがわかった。As is clear from Table 3, the case where the (a 1 ) electrode to (a 4 ) electrode of the present invention is used is compared with the case where the (x 1 ) electrode to (x 4 ) electrode is used. It was found that the discharge capacity was high. Thus, it was found that the discharge capacity was increased by using the hydrogen storage alloy of the present invention as a negative electrode material.
【００３０】次に、窒素処理により、耐食性に変化が生
じるかどうかを調べるために以下のような実験をおこな
った。 〔実験２〕本発明の（ａ1 ）電極〜（ａ4 ）電極、比較
例の（ｘ1 ）電極〜（ｘ4 ）電極を用いてサイクル特性
を調べたので、その結果を表４に示す。Next, the following experiment was conducted to examine whether or not the corrosion resistance was changed by the nitrogen treatment. Experiment 2] of the present invention (a 1) electrodes ~ (a 4) electrode, since the cycle characteristics were examined by using the (x 1) electrodes ~ (x 4) electrodes of the comparative example, the results are shown in Table 4 .
【００３１】尚、実験としては、上記実験２と同様の単
電池を用い、上記充放電条件と同様の充放電サイクルを
繰り返し、５００サイクル目の容量維持率を求めた。In the experiment, a single cell similar to that in Experiment 2 was used, and the same charge / discharge cycle as in the above charge / discharge conditions was repeated, and the capacity retention ratio at the 500th cycle was obtained.
【００３２】[0032]
【表４】 [Table 4]
【００３３】表４から明らかなように、本発明の
（ａ1 ）電極〜（ａ4 ）電極は、熱処理を行わなかった
（ｘ4 ）電極と比べてサイクル特性がよく、（ｘ1 ）電
極〜（ｘ3）電極と比べてもサイクル特性に遜色はなか
った。以上のことより、窒素を含んだガス中で熱処理を
行っても、通常の熱処理をおこなった場合と遜色なく耐
食性が向上することがわかった。 〔その他の事項〕熱処理温度は上記実施例に限るもので
はなく、４００℃〜水素吸蔵合金の融点の１００℃以下
の温度範囲（望ましくは１０００℃付近）で熱処理を行
うことができる。As is clear from Table 4, the (a 1 ) electrode to (a 4 ) electrode of the present invention have better cycle characteristics than the (x 4 ) electrode that has not been heat-treated, and the (x 1 ) electrode Cycle characteristics were not inferior to the (x 3 ) electrode. From the above, it was found that even when the heat treatment was performed in a gas containing nitrogen, the corrosion resistance was improved as well as when the normal heat treatment was performed. [Other Matters] The heat treatment temperature is not limited to the above embodiment, and the heat treatment can be performed in a temperature range of 400 ° C. to 100 ° C. or less of the melting point of the hydrogen storage alloy (preferably around 1000 ° C.).
【００３４】また、処理時間についても上記実施例に限
ることなく、２時間以上の処理時間で処理を行うことが
できる。また、上記実施例では、熱処理において流すガ
スの全圧を１ａｔｍとしたが、１ａｔｍ以上の圧力で行
うこともできる。さらに、上記した処理を行う際の、温
度、時間、圧力の条件を様々に変化させることによっ
て、合金に含有させる窒素量をさらに向上させることが
できると考えられる。The processing time is not limited to the above embodiment, and the processing can be performed in a processing time of 2 hours or more. Further, in the above embodiment, the total pressure of the gas flowing in the heat treatment was set to 1 atm, but the heat treatment may be performed at a pressure of 1 atm or more. Furthermore, it is considered that the amount of nitrogen contained in the alloy can be further improved by variously changing the conditions of temperature, time, and pressure when performing the above-described processing.
【００３５】[0035]
【発明の効果】以上説明したように、本発明によれば、
水素吸蔵合金の耐食性を向上させつつ、水素吸蔵量を増
加させることができるという効果を奏した。加えて、こ
のような水素吸蔵合金をアルカリ蓄電池の負極材料とし
て用いることにより、耐食性が高く、且つ、充放電容量
の高い、優れた水素吸蔵合金電極を提供することができ
る。As described above, according to the present invention,
This has the effect of increasing the hydrogen storage amount while improving the corrosion resistance of the hydrogen storage alloy. In addition, by using such a hydrogen storage alloy as a negative electrode material of an alkaline storage battery, an excellent hydrogen storage alloy electrode having high corrosion resistance and high charge / discharge capacity can be provided.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 西尾 晃治 守口市京阪本通２丁目18番地 三洋電機 株式会社内 (72)発明者 古川 修弘 守口市京阪本通２丁目18番地 三洋電機 株式会社内 (56)参考文献 特公 昭61−41977（ＪＰ，Ｂ１) (58)調査した分野(Int.Cl.7，ＤＢ名) H01M 4/38 C22C 19/00 H01M 4/24 - 4/26 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Koji Nishio 2-18-18 Keihanhondori, Moriguchi City Sanyo Electric Co., Ltd. (72) Inventor Furukawa 2-18-18 Keihanhondori Moriguchi City, Sanyo Electric Co. 56) References JP-B-61-41977 (JP, B1) (58) Fields investigated (Int. Cl. 7 , DB name) H01M 4/38 C22C 19/00 H01M 4/24-4/26
Claims (5)
類金属の混合物)とNiを主体とする水素吸蔵合金におい
て、窒素を含む雰囲気中で熱処理が施されることにより
金属格子間に窒素原子が侵入されてあることを特徴とす
る水素吸蔵合金。1. A hydrogen storage alloy mainly composed of Mm (a mixture of rare earth metals) and Ni, which absorbs and releases hydrogen, and is subjected to a heat treatment in an atmosphere containing nitrogen, whereby nitrogen atoms are interposed between metal lattices. A hydrogen storage alloy, characterized in that hydrogen has been invaded.
であることを特徴とする請求項１に記載の水素吸蔵合The hydrogen storage compound according to claim 1, wherein
金。Money.
雰囲気であることを特徴とする請求項１に記載の水素吸The hydrogen absorption according to claim 1, wherein the atmosphere is an atmosphere.
蔵合金。Zou alloy.
むことを特徴とする請求項１から３の何れかに記載の水The water according to any one of claims 1 to 3, wherein
素吸蔵合金。Element storage alloy.
吸蔵合金を主成分とすることを特徴とするアルカリ蓄電Alkaline power storage characterized by using an occlusion alloy as a main component
池用水素吸蔵合金電極。Hydrogen storage alloy electrode for pond.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20150892A JP3268015B2 (en) | 1992-07-28 | 1992-07-28 | Hydrogen storage alloy and hydrogen storage alloy electrode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20150892A JP3268015B2 (en) | 1992-07-28 | 1992-07-28 | Hydrogen storage alloy and hydrogen storage alloy electrode |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0652854A JPH0652854A (en) | 1994-02-25 |
| JP3268015B2 true JP3268015B2 (en) | 2002-03-25 |
Family
ID=16442214
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20150892A Expired - Fee Related JP3268015B2 (en) | 1992-07-28 | 1992-07-28 | Hydrogen storage alloy and hydrogen storage alloy electrode |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3268015B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4659936B2 (en) * | 1999-09-30 | 2011-03-30 | 株式会社東芝 | Hydrogen storage alloy, method for producing the same, secondary battery using the same, and electric vehicle |
-
1992
- 1992-07-28 JP JP20150892A patent/JP3268015B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0652854A (en) | 1994-02-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH02277737A (en) | Electrode made of hydrogen storage alloy | |
| JP6276031B2 (en) | Hydrogen storage alloy powder, negative electrode and nickel metal hydride secondary battery | |
| JP2680669B2 (en) | Hydrogen storage alloy electrode for alkaline storage battery | |
| JP7311507B2 (en) | Large-capacity and long-life La-Mg-Ni type negative electrode hydrogen storage material for secondary chargeable nickel-metal hydride battery and method for producing the same | |
| US5776626A (en) | Hydrogen-occluding alloy and hydrogen-occluding alloy electrode | |
| JP3266980B2 (en) | Hydrogen storage alloy, method for producing the same, and hydrogen storage alloy electrode | |
| JP3268015B2 (en) | Hydrogen storage alloy and hydrogen storage alloy electrode | |
| JP6934097B1 (en) | Hydrogen storage alloy | |
| EP1030392B1 (en) | Hydrogene storage alloy electrode and method for manufacturing the same | |
| JPS62271349A (en) | Hydrogen occlusion electrode | |
| JPS62271348A (en) | Hydrogen occlusion electrode | |
| JP2000234134A (en) | Hydrogen storage alloy, and electrode using the same | |
| JP2792955B2 (en) | Hydrogen storage alloy for hydrogen electrode | |
| JP3272012B2 (en) | Hydrogen storage alloy | |
| JP3192694B2 (en) | Alkaline storage battery | |
| JP2999785B2 (en) | Hydrogen storage alloy electrode for alkaline storage batteries | |
| JP2000182607A (en) | Hydrogen storage alloy electrode | |
| WO2020179752A1 (en) | Negative electrode active material powder, negative electrode and nickel hydrogen secondary battery | |
| JP3123800B2 (en) | Hydrogen storage alloy electrode | |
| JPH0675398B2 (en) | Sealed alkaline storage battery | |
| JP2680566B2 (en) | Hydrogen storage electrode | |
| JP3369148B2 (en) | Alkaline storage battery | |
| JP3432844B2 (en) | Evaluation method of hydrogen storage alloy electrode | |
| JP3322452B2 (en) | Rare earth hydrogen storage alloy for alkaline storage batteries | |
| JP3432866B2 (en) | Hydrogen storage alloy electrodes for alkaline storage batteries |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090111 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100111 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100111 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110111 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110111 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120111 Year of fee payment: 10 |
|
| LAPS | Cancellation because of no payment of annual fees |