【発明の詳細な説明】[Detailed description of the invention]
本発明はアルカリ電池特に酸化銀電池の正極合
剤の改良に関するものである。
従来の酸化銀電池の正極合剤は、例えば酸化銀
95部と黒鉛4.5部とを混合し、結着剤であるポリ
スチロール0.5部の溶剤溶液により混練し、撹拌
しながら乾燥して均一に混合された正極合剤を得
ていた。この正極合剤をプレスで成形し、リング
と共に正極容器に充填していた。
しかし、従来の正極合剤を用いた酸化銀電池は
放電作動電圧が平坦であるが低く、重負荷および
低温性能においても充分ではなく、さらに、酸化
銀が非常に高価な活物質である欠点を有してい
た。
また、電卓等には酸化銀電池が使用され高価な
ものになつていた。
本発明は高価な酸化銀の代りに酸化ニツケルを
添加し黒鉛と混合することにより、特に重負荷、
低温性能に優れ、高い放電作動電圧を長時間維持
し、低価格で充分使用可能なアルカリ電池を得る
ことを目的としている。
本発明の実施例のアルカリ電池を図面にもとづ
いて説明する。
第2図イのごとく、酸化銀(Ag2O)85部と黒
鉛1.7部とをポリスチロール0.8部の溶剤溶液でミ
キサーで混練乾燥し、造粒してなつた個々の粒子
1の表面に、オキシ水酸化ニツケル(NiOOH)
15部と黒鉛0.79部(5%に相当)に少量の電解液
を加えて混合乾燥した混合粉2を、全面に被覆せ
しめた正極合剤3が、第1図の鋼にニツケルメツ
キした正極容器4に加圧充填されている。正極合
剤3の負極との対向面に接して載置された微孔性
ナイロン膜の隔離材5とポリビニールアルコール
の不織布からなる電解液保持材6とを介して、ア
マルガム亜鉛粉末とポリアクリル酸等の糊剤とに
よるゲル状負極7が収納されている。さらに、鋼
にニツケルメツキした封口板8で絶縁ガスケツト
9を介して正極容器4の開口部10を内方へ加圧
折曲して締めつけ、電池を密封口し完成してい
る。
本発明電池は正極合剤3中に高価な酸化銀の代
りに本体10分の1の価格である酸化ニツケルを添
加するため、正極合剤3のコストを大幅に下げる
ことができると共に、正極合剤3全体で両活物質
により合成された高い作動電圧を長時間維持でき
るようになり、酸化銀電池を用いている電卓等に
充分使用でき、安価に提供できるものである。
また第2図ロのごとく、正極合剤3の正極容器
4への充填を、底部分11が酸化銀(Ag2O)と
黒鉛との混合粉を主体とし、負極との対向部分1
2がオキシ水酸ニツケルと黒鉛との混合粉を主体
となるよう配置することにより、特に、放電初期
の電圧が酸化銀の放電作動電圧(約1.55V)オキ
シ水酸化ニツケルの放電作動電圧(約1.65V)と
で合成された平坦で高い電池放電作動電圧を得
て、その分後半に放電持続時間を伸ばせるもので
ある。
次に、正極合剤3中の酸化銀(Ag2O)に対す
るオキシ水酸化ニツケル(NiOOH)の使用割合
が15%である外径11.6mm、高さ5.4mmのボタン型
酸化銀電池SR44の本発明品〔A〕と、酸化銀100
%の従来品〔B〕と20℃で125Ω連続放電、20℃
と0℃で60Ω連続放電を行つた結果を表1にまと
めた。
The present invention relates to improvements in positive electrode mixtures for alkaline batteries, particularly silver oxide batteries. The positive electrode mixture of conventional silver oxide batteries is, for example, silver oxide.
95 parts of graphite and 4.5 parts of graphite were mixed, kneaded with a solvent solution of 0.5 part of polystyrene as a binder, and dried while stirring to obtain a uniformly mixed positive electrode mixture. This positive electrode mixture was molded using a press and filled into a positive electrode container together with a ring. However, silver oxide batteries using conventional positive electrode mixtures have a flat but low discharge operating voltage, are not sufficient in heavy load and low temperature performance, and have the disadvantage that silver oxide is a very expensive active material. had. In addition, silver oxide batteries were used in calculators and the like, making them expensive. The present invention has been developed by adding nickel oxide instead of expensive silver oxide and mixing it with graphite, especially for heavy loads.
The objective is to obtain an alkaline battery that has excellent low-temperature performance, maintains a high discharge operating voltage for a long time, and is fully usable at a low price. An alkaline battery according to an embodiment of the present invention will be explained based on the drawings. As shown in Fig. 2A, 85 parts of silver oxide (Ag 2 O) and 1.7 parts of graphite are mixed and dried in a mixer with a solvent solution of 0.8 parts of polystyrene, and the particles are granulated onto the surface of each particle 1. Nickel oxyhydroxide (NiOOH)
A cathode container 4 made of nickel-plated steel on the steel shown in Fig. 1 is coated with a cathode mixture 3, which is made by mixing and drying a mixed powder 2 of 15 parts of graphite and 0.79 parts of graphite (equivalent to 5%) with a small amount of electrolyte and drying. is pressurized and filled. The amalgam zinc powder and the polyacrylic material are passed through the isolation material 5, which is a microporous nylon membrane placed in contact with the surface of the positive electrode mixture 3 facing the negative electrode, and the electrolyte holding material 6, which is made of a non-woven fabric made of polyvinyl alcohol. A gel-like negative electrode 7 made of a glue such as acid is housed. Furthermore, the opening 10 of the positive electrode container 4 is bent inward with pressure using a sealing plate 8 made of nickel-plated steel, and the battery is sealed. In the battery of the present invention, nickel oxide, which is one-tenth the price of the main body, is added to the positive electrode mixture 3 instead of expensive silver oxide, so the cost of the positive electrode mixture 3 can be significantly reduced. The entire agent 3 can maintain a high operating voltage synthesized by both active materials for a long time, and can be sufficiently used in calculators and the like using silver oxide batteries, and can be provided at low cost. In addition, as shown in FIG. 2B, the positive electrode mixture 3 is filled into the positive electrode container 4 in such a way that the bottom part 11 is mainly composed of a mixed powder of silver oxide (Ag 2 O) and graphite, and the part 1 facing the negative electrode is filled with the positive electrode mixture 3.
By arranging the powder so that 2 is mainly a mixed powder of nickel oxyhydroxide and graphite, the voltage at the initial stage of discharge can be increased from the discharge operating voltage of silver oxide (approximately 1.55V) to the discharge operating voltage of nickel oxyhydroxide (approximately 1.55V). 1.65V) to obtain a flat and high battery discharge operating voltage, which can extend the discharge duration in the second half. Next, we will introduce a button-type silver oxide battery SR44 with an outer diameter of 11.6 mm and a height of 5.4 mm, in which the ratio of nickel oxyhydroxide (NiOOH) to silver oxide (Ag 2 O) in positive electrode mixture 3 is 15%. Invention [A] and silver oxide 100
% conventional product [B] and 125Ω continuous discharge at 20℃, 20℃
Table 1 summarizes the results of 60Ω continuous discharge at 0°C.
【表】
表1の結果、本発明品〔A〕は従来品〔B〕よ
り優れていることがわかる。
また、本発明は過酸化銀(AgO)を主活物質
とするアルカリ電池においても、大幅なコストダ
ウンが可能であり、過酸化銀(AgO)と酸化ニ
ツケル〔Ni(OH)2〕との組合せも、酸化還元反
応が起り効果がある。
以上のごとく、本発明の酸化銀もしくは酸化銀
と黒鉛とからなる粒子の表面に、酸化ニツケルと
黒鉛との混合粉を被覆してなる正極合剤を用いた
アルカリ電池は、高価な酸化銀を活物質の使用量
を減らすためコストが安く、さらに特に重負荷、
低温性能に優れ高い放電作動電圧を長時間維持
し、その工業的価値は大なるものである。[Table] The results in Table 1 show that the product [A] of the present invention is superior to the conventional product [B]. Furthermore, the present invention enables significant cost reduction in alkaline batteries that use silver peroxide (AgO) as the main active material, and the combination of silver peroxide (AgO) and nickel oxide [Ni(OH) 2 ] Also, redox reactions occur and are effective. As described above, an alkaline battery using a positive electrode mixture in which the surface of particles of silver oxide or silver oxide and graphite is coated with a mixed powder of nickel oxide and graphite according to the present invention does not use expensive silver oxide. The cost is low because the amount of active material used is reduced, and it is especially suitable for heavy loads.
It has excellent low-temperature performance and maintains a high discharge operating voltage for a long time, making it of great industrial value.
【図面の簡単な説明】[Brief explanation of drawings]
第1図は本発明の実施例のボタン型アルカリ電
池の断面図で、第2図イは酸化銀と黒鉛との混合
造粒した粒子の表面に、オキシ水酸化ニツケルと
黒鉛との混合粉を被覆した正極合剤の拡大図、ロ
は酸化銀を主体とした底部分とオキシ水酸化ニツ
ケルを主体とした対向部分とに構成され充填され
た正極合剤の説明図である。
1……粒子、2……混合粉、3……正極合剤、
4……正極容器、11……底部分、12……対向
部分。
Fig. 1 is a cross-sectional view of a button-type alkaline battery according to an embodiment of the present invention, and Fig. 2A shows a mixed powder of nickel oxyhydroxide and graphite on the surface of mixed granulated particles of silver oxide and graphite. An enlarged view of the coated positive electrode mixture, and (b) an explanatory view of the positive electrode mixture configured and filled in a bottom part mainly composed of silver oxide and an opposing part mainly composed of nickel oxyhydroxide. 1... Particles, 2... Mixed powder, 3... Positive electrode mixture,
4... Positive electrode container, 11... Bottom part, 12... Opposing part.