JPS60148062A - Primary battery - Google Patents

Abstract

PURPOSE:To provide steady discharge performance and reduce battery thickness by mixing gold plated stainless steel fibers to positive active material powder. CONSTITUTION:Manganese dioxide powder is used as active material of a positive mix 2. Stainless steel fibers having a gold plating layer of 0.03-0.10mum in thickness on thier surfaces are mixed as auxiliary conductor and binder to manganese dioxide powder. Fibers having a mean diameter of 5-5mum and a length of 2-5mm. are used. 2pts.wt. fibers are mixed to 98pts.wt. manganese dioxide powder. By this mixing, increase of internal resistance during discharge is suppressed, and thickness of a battery can be reduced.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、アルカリ電池やリチウム電池などの一次電池
に関するもので、特に薄形電池の改良に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to primary batteries such as alkaline batteries and lithium batteries, and particularly to improvements in thin batteries.

従来例の構成とその問題点 従来のこの種薄形電池で、正極に水銀、銀マンガン、ニ
ッケルなどの酸化物を使用する電池の場合、放電によっ
て成形正極合剤が膨張する。しかし活物質粒子間が拡大
され、その結果、電池の内部抵抗が上昇し、電池の厚さ
く高さ）が大きくなる傾向にあった。Structure of the conventional example and its problems When a conventional thin battery of this type uses an oxide of mercury, silver manganese, nickel, etc. for the positive electrode, the molded positive electrode mixture expands due to discharge. However, the distance between the active material particles is enlarged, and as a result, the internal resistance of the battery increases, and the battery tends to become thicker and taller.

内部抵抗の上昇を防止する目的で、従来では、上記の正
極活物質粉に電導助剤として黒鉛の微粉末を混合する方
法が採用されているが、その場合においても、内部抵抗
は高く、上昇の傾向にあった。しかも電池の厚さく高さ
）は放電時間を経るにしだがってプラスの方に変位して
くる。In order to prevent an increase in internal resistance, conventionally a method has been adopted in which fine graphite powder is mixed into the above-mentioned positive electrode active material powder as a conductive agent, but even in that case, the internal resistance remains high and increases. There was a tendency to Moreover, the thickness (height and thickness of the battery) shifts in the positive direction as the discharge time passes.

これは、正極活物質を構成している金属酸化物粒子間に
、放電過程で電解液が侵入して正極合剤が膨張し、金属
ケースを内部より押し上げるために、電池の高さが大き
くなるのである。This is because the electrolyte enters between the metal oxide particles that make up the positive electrode active material during the discharge process, causing the positive electrode mixture to expand and push up the metal case from inside, increasing the height of the battery. It is.

これらを解決するために、正極活物質に短く切断した繊
維状の不銹鋼を混合し、正極粒子をこの繊維によってか
らませ、膨張を防止させる方法がとられていた。この場
合には、混合した不銹銅繊維素の表面に不働態化酸化層
が形成嘔れ、高温での保存中における放電持続時間が大
きく減少する欠点が生じる。In order to solve these problems, a method has been used in which fibrous stainless steel cut into short pieces is mixed with the positive electrode active material, and the positive electrode particles are entangled with the fibers to prevent expansion. In this case, a passivating oxidation layer is formed on the surface of the mixed non-corrosive copper cellulose, resulting in a drawback that the discharge duration during storage at high temperatures is greatly reduced.

発明の目的　゛ 本発明は、放電中に卦ける内部抵抗の上昇をおさえ、安
定した放電特柾をもたせるとともに、電池の厚み（高さ
）が大きくなることを防止することを目的とする。Purpose of the Invention An object of the present invention is to suppress the increase in internal resistance that occurs during discharge, provide stable discharge characteristics, and prevent the thickness (height) of the battery from increasing.

発明の構成 本発明は、正極活物質粉末の中に、表面をω片した不銹
銅繊維素を混合させることを特徴とするものである。こ
のような構成による正極合剤を使用する薄形電池は、保
存特性にすぐれ、内部抵抗の上昇が少なく、かつ放電に
よる高さ膨張のない電池となる。Structure of the Invention The present invention is characterized in that a non-rusting copper cellulose having an ω-shaped surface is mixed into a positive electrode active material powder. A thin battery using a positive electrode mixture having such a configuration has excellent storage characteristics, has a small increase in internal resistance, and does not expand in height due to discharge.

実施例の説明 以下、本発明の詳細な説明する。ここでは、ボタン型の
薄形アルカリ電池ＬＲ１１２０（外径１１、ｆｌｌｌｌ
ｍ、高ｄ２．０朋）について説明する。DESCRIPTION OF EMBODIMENTS The present invention will now be described in detail. Here, a button-type thin alkaline battery LR1120 (outer diameter 11, flllll
m, high d2.0) will be explained.

第１図において、１は鉄地ケースの表面にニッケルメッ
キをした正極ケースであり、正極端子をかねる。その内
面には、正極合剤２が加圧成形されている。正極ケース
の内側部と接する箇所には台座リング３が嵌着されて集
電効果を上げている。In FIG. 1, reference numeral 1 denotes a positive electrode case with nickel plating on the surface of the iron case, which also serves as a positive electrode terminal. A positive electrode mixture 2 is pressure-molded on the inner surface thereof. A pedestal ring 3 is fitted at a location in contact with the inside of the positive electrode case to improve the current collecting effect.

材質は鉄地にニッケルメッキをしたものが使用される。The material used is nickel-plated iron.

４１１−ｊ：セパレータ、５は電解液含浸材の層である
。６は負極容器であり、その外表面は負極端子をかねる
。その内部には、水化した亜鉛粉末がゲル電解液と均一
に混合でれた分散状の負極合剤７が充填されている。８
は耐アルカリ性プラスチックよりなるガスケットであり
、負極容器の周縁部に位置しリング状をなし、正極ケー
ス開口部を電池内方向に曲げ、内部からの電解液の漏出
を防止するバッキングの役をしている。411-j: separator; 5 is a layer of electrolyte-impregnated material; 6 is a negative electrode container, the outer surface of which serves as a negative electrode terminal. The interior thereof is filled with a dispersed negative electrode mixture 7 in which hydrated zinc powder is uniformly mixed with a gel electrolyte. 8
is a ring-shaped gasket made of alkali-resistant plastic, located at the periphery of the negative electrode container, bends the opening of the positive electrode case toward the inside of the battery, and serves as a backing to prevent electrolyte from leaking from inside. There is.

本発明は、正極合剤２に関する改良であるが、活物質と
して二酸化マンガンを粉粒状と々し、これに電導助剤及
び結着剤のような役目をσせるだめ、表面に０・０３〜
０．１０μｍ厚の金メッキをほどこした不銹鋼繊維を混
合させる。その繊維径は５〜５μｍ、たて方向の長さ２
〜５闘のものを用いた。活物質との混合比は、二酸化マ
ンガン９８に対し繊維２の重量比で用いた。、 これらを均一に攪拌混合し、一定量を採取して加圧成形
し１円板状の正極合剤２を形成する。The present invention is an improvement on the positive electrode mixture 2, in which manganese dioxide is pulverized as an active material, and the surface is coated with 0.03~
A stainless steel fiber plated with gold to a thickness of 0.10 μm is mixed. The fiber diameter is 5 to 5 μm, and the length in the vertical direction is 2
~5 fights were used. The mixing ratio with the active material was 98 parts manganese dioxide to 2 parts by weight of fiber. , These are uniformly stirred and mixed, and a certain amount is sampled and pressure-molded to form a disk-shaped positive electrode mixture 2.

玄 上記の構成の電池Ａとし、比較例として二酸化ハ マンガン粉に黒鉛粉末を混合した合剤を使用した電池を
Ｂ、不銹鋼繊維を混合し、た合剤を使用した１池をＣと
する。A battery with the above configuration is referred to as B, a battery using a mixture of hamanganese dioxide powder and graphite powder as a comparative example is referred to as B, and a battery using a mixture of stainless steel fiber is referred to as C.

次に、とれらの電池の特性を比較した結果を説明する。Next, the results of comparing the characteristics of these batteries will be explained.

７’？、（７）放電特性及び内部抵抗を示す。放電持続
時間では、本発明の電池Ａが一番長く、反応効率の高い
ことを示している。また、内部抵抗の水準も低く、かつ
、その変化が少ないことが認められる。7'? , (7) shows discharge characteristics and internal resistance. In terms of discharge duration, battery A of the present invention has the longest discharge duration, indicating that it has a high reaction efficiency. Furthermore, it is recognized that the level of internal resistance is low and its change is small.

第３図は温度６０°Ｃ相対湿度９０％のもとで保存した
後の容量維持率を示すもので、放電条件は３０にΩ連続
放電（２０’Ｃ）であり、組立直後の初期放電時間を１
００とし、保存後における持続時間を比でもって表わし
た。上記高温多湿下での保存を１００日（２４００時間
）まで測定しだが電池Ｂは８６％、Ｃは７０％であるの
に対し、電池人は９５％の維持率であった。電池Ｃは正
極合剤中に混合されている不銹鋼繊維の表面に、不働態
化膜の生成により、電池の内部抵抗が増大することによ
る特性の劣化と考えられる。本発明の電池Ａは表面を金
メッキした不銹鋼繊維を使用して作るために、不働態化
膜が生成式れず安定な保存特性をうるととができた。Figure 3 shows the capacity retention rate after storage at a temperature of 60°C and a relative humidity of 90%.The discharge conditions were 30Ω continuous discharge (20'C), and the initial discharge time immediately after assembly. 1
00, and the duration after storage was expressed as a ratio. Storage under the above-mentioned high temperature and high humidity conditions was measured for up to 100 days (2400 hours), and the retention rate of Battery B was 86% and that of Battery C was 70%, while Battery Man had a retention rate of 95%. It is thought that the characteristics of Battery C deteriorated due to an increase in the internal resistance of the battery due to the formation of a passivation film on the surface of the stainless steel fibers mixed in the positive electrode mixture. Since the battery A of the present invention is made using stainless steel fibers whose surfaces are plated with gold, no passivation film is formed and stable storage characteristics can be obtained.

第４図は放電中の電池膨張を示すもので、放電条件は３
０にΩ連続放電（２０°Ｃ）とし、放電開始時の電池高
さを変４丸０とし、放電終了までの電池高さの変位を表
わした。Figure 4 shows the battery expansion during discharge, and the discharge conditions are 3.
Ω continuous discharge (20° C.) was set at 0, the height of the battery at the start of discharge was set as 0 with 4 circles, and the displacement of the battery height until the end of discharge was expressed.

従来例の電池Ｂは終了時０．３朋、電池Ｃは０．１闘で
あったのに対して本発明電池Ａでは、放電過程における
高き変位はみられない。数値的には＋０．０５間の実測
値を得た。これは、正極活物質の二酸化マンガン粒子と
繊維が立体的にからみ合い、さらに加圧成形されている
ために、膨張の力を押えこんて、高さ変化がきわめて少
なくなったことによるものである。While the conventional battery B had a discharge of 0.3 and the battery C had a discharge of 0.1 at the end, in the battery A of the present invention, no high displacement was observed during the discharge process. Numerically, actual values between +0.05 were obtained. This is because the manganese dioxide particles and fibers of the positive electrode active material are intertwined three-dimensionally and are further pressure-molded, which suppresses the force of expansion and minimizes height changes. .

発明の効果 以上のように、本発明は、安定した放電特性を示すとと
もに保存特性にすぐれ、埒らに電池ふくらみがなく、機
器への装着性にすぐれた電池を提供することができる。Effects of the Invention As described above, the present invention can provide a battery that exhibits stable discharge characteristics, has excellent storage characteristics, is free from battery bulges, and is easy to attach to equipment.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明の実施例による電池の縦断面図、第２図
は放電特性と内部抵抗変化を示す図、第３図は保存後の
容量維持率を示す図、第４図は放電による電池高さ変化
を示す図である。 １・・・・・・正極ケース、２・・・・・正極合剤、４
・・・・・・セパレータ、６・・・・・・負極容器、７
・・・・・・負極合剤、８・・・・・・ガスケット。 代理人の氏名　弁理士　中　尾　敏　男　ほか１名第１
図 第２図 ０　２００　４６ｔ）　６００　＆に ｉｔ、時間　（（とＳ） 第　３　＠ 保存期間（幻 ｏ　ｚｏｏ　４００　６００　θ〃 方（ｅ　則１　間　（八とＳ）Figure 1 is a longitudinal cross-sectional view of a battery according to an embodiment of the present invention, Figure 2 is a diagram showing discharge characteristics and internal resistance changes, Figure 3 is a diagram showing capacity retention rate after storage, and Figure 4 is a diagram showing discharge characteristics. It is a figure which shows a battery height change. 1...Positive electrode case, 2...Positive electrode mixture, 4
... Separator, 6 ... Negative electrode container, 7
...Negative electrode mixture, 8... Gasket. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 0 200 46t) 600 & it, time ((and S) 3rd @ storage period (illusion o zoo 400 600 θ〃 direction (e rule 1 between (8 and S)

Claims (1)

【特許請求の範囲】[Claims] 金メッキした不銹鋼繊維を混合した正極合剤を備えた一
次電池。A primary battery with a positive electrode mix made of gold-plated stainless steel fibers.