JP3248332B2 - Alkaline battery - Google Patents
Alkaline batteryInfo
- Publication number
- JP3248332B2 JP3248332B2 JP02791694A JP2791694A JP3248332B2 JP 3248332 B2 JP3248332 B2 JP 3248332B2 JP 02791694 A JP02791694 A JP 02791694A JP 2791694 A JP2791694 A JP 2791694A JP 3248332 B2 JP3248332 B2 JP 3248332B2
- Authority
- JP
- Japan
- Prior art keywords
- gasket
- thin
- alkaline battery
- explosion
- battery
- 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
- 238000012545 processing Methods 0.000 description 6
- 239000007788 liquid Substances 0.000 description 5
- 238000000465 moulding Methods 0.000 description 5
- 239000011347 resin Substances 0.000 description 4
- 229920005989 resin Polymers 0.000 description 4
- 238000012360 testing method Methods 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 239000004677 Nylon Substances 0.000 description 1
- 239000006182 cathode active material Substances 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229920001778 nylon Polymers 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 239000007774 positive electrode material Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/10—Primary casings; Jackets or wrappings
- H01M50/147—Lids or covers
- H01M50/148—Lids or covers characterised by their shape
- H01M50/154—Lid or cover comprising an axial bore for receiving a central current collector
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/30—Arrangements for facilitating escape of gases
- H01M50/342—Non-re-sealable arrangements
- H01M50/3425—Non-re-sealable arrangements in the form of rupturable membranes or weakened parts, e.g. pierced with the aid of a sharp member
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Sealing Battery Cases Or Jackets (AREA)
- Gas Exhaust Devices For Batteries (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明はアルカリ電池のガスケッ
トに関し、特に、電池内圧が異常に高まったときに破断
してガスを安全に放出させる防爆型ガスケットに関する
ものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gasket for an alkaline battery, and more particularly, to an explosion-proof gasket that breaks when the internal pressure of the battery becomes abnormally high and releases gas safely.
【０００２】[0002]
【従来の技術】一般に、アルカリ電池は誤使用などによ
り過充電、過放電された場合に激しいガス発生が起こり
電池内圧が異常に上昇し、その結果として、漏液を起こ
したり、場合によっては破裂を引き起こす危険性があ
る。従って、アルカリ電池については、ガス発生により
電池内圧が上昇した場合、内部のガスを強制的に外部に
排気させるための防爆機構を設けている。2. Description of the Related Art Generally, when an alkaline battery is overcharged or overdischarged due to misuse or the like, severe gas generation occurs and the internal pressure of the battery rises abnormally. As a result, a liquid leak or a rupture may occur. Risk of causing Therefore, the alkaline battery is provided with an explosion-proof mechanism for forcibly exhausting the internal gas to the outside when the internal pressure of the battery increases due to gas generation.
【０００３】通常、アルカリ電池では、プラスチックま
たはゴム製のガスケットを用い底板、集電体などと組合
せ電池ケースの開口部を封止する構造をとっており、こ
のガスケットの一部に薄肉部を設け、ガス発生による電
池内圧の応力集中により、薄肉部を破断させる機構が提
案されている。（例えば特開昭５９−１３９５４９号公
報）Normally, an alkaline battery has a structure in which a plastic or rubber gasket is used to seal an opening of a battery case in combination with a bottom plate, a current collector, etc., and a thin portion is provided in a part of the gasket. A mechanism has been proposed in which a thin portion is broken by stress concentration due to internal pressure of the battery due to gas generation. (For example, JP-A-59-139549)
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、このよ
うな薄肉部を樹脂成形加工することは、成形加工技術
上、または金型加工精度上の観点より問題があり、通常
成形加工できる薄肉厚みとしては０．３〜０．５ｍｍが
最低限度であり、防爆機構の安全性、信頼性を確保する
べく、その作動圧をさらに減少させるため、この薄肉部
と厚肉部の連結部分に二次加工により０．１〜０．２ｍ
ｍの切欠部を設け、ガスケットの耐圧強度を低下させ破
断しやすくさせている。しかし、前記薄肉部の最小厚み
が０．１〜０．２ｍｍとした場合二次加工における加工
寸法が安定させにくく、且つ電池組立品を高温保存時
（例えば６０℃保存）樹脂の劣化、収縮などにより微量
のガス発生でも薄肉部が破断するという問題点があっ
た。However, resin molding of such a thin portion has a problem from the viewpoint of molding technology or mold processing accuracy. 0.3-0.5mm is the minimum limit, and in order to further secure the safety and reliability of the explosion-proof mechanism, in order to further reduce the working pressure, the connecting part of this thin part and thick part is subjected to secondary processing. 0.1-0.2m
A notch of m is provided to reduce the pressure resistance of the gasket to facilitate breakage. However, when the minimum thickness of the thin portion is 0.1 to 0.2 mm, it is difficult to stabilize the processing dimensions in the secondary processing, and when the battery assembly is stored at a high temperature (for example, stored at 60 ° C.), the resin deteriorates and shrinks. As a result, there is a problem that the thin portion is broken even with a small amount of gas generated.
【０００５】そこで、本発明は上記の問題点を解決すべ
く、高温保存において安定した耐漏液性能を確保しつ
つ、しかもガス発生による電池内圧において一定圧力で
確実に破断するガスケットの形状規制をすることによ
り、耐漏液性、防爆作動性に優れたアルカリ電池を提供
するものである。In order to solve the above-mentioned problems, the present invention regulates the shape of a gasket that reliably breaks at a constant pressure in a battery internal pressure due to gas generation while ensuring stable liquid leakage resistance during high-temperature storage. This provides an alkaline battery having excellent resistance to liquid leakage and explosion-proof operation.
【０００６】[0006]
【課題を解決するための手段】本発明者らはこの目的に
沿って、ガスケット形状を鋭意検討した結果、従来のガ
スケット形状の薄肉部と厚肉部との連結部のコーナー部
がＲ＝０．０２ｍｍ以下または面取りがＣ＝０．０２ｍ
ｍ以下であるＲ部、面取り部の寸法形状を規制したガス
ケットを用いることにより、信頼性の高い防爆機構を確
保した。The inventors of the present invention have studied the shape of the gasket for this purpose, and as a result, the corner of the connecting portion between the thin portion and the thick portion of the conventional gasket has R = 0. 0.02 mm or less or C = 0.02 m
A highly reliable explosion-proof mechanism was secured by using a gasket in which the dimensions and shapes of the R portion and the chamfered portion which were not more than m were regulated.
【０００７】[0007]
【作用】本発明のガスケットは、その一部に薄肉部を設
けた防爆構造を有するガスケットで、電池内部のガス発
生により薄肉破断時の起点部分となる薄肉部と厚肉部と
の連結部のＲ部・面取り部のＲ寸法・Ｃ寸法の規制をす
ることにより、起点部分の亀裂の入りやすさ（ノッチ効
果）を高め、薄肉部の厚みを同じに設定した場合でもガ
ス内部圧力による薄肉部の破断圧力を低くめ、かつバラ
ツキの小さい安定した防爆構造を得るとともに、従来の
薄肉部厚みを維持することにより高温保存での耐漏液性
についても従来通りの性能を確保した。The gasket of the present invention is a gasket having an explosion-proof structure in which a thin portion is provided in a part thereof. The gasket has a connection portion between a thin portion and a thick portion which becomes a starting point at the time of thin break due to gas generation inside the battery. By regulating the R and C dimensions of the R and chamfered parts, the cracks at the starting point are easily cracked (notch effect), and even when the thickness of the thin part is set to be the same, the thin part due to the gas internal pressure The rupture pressure was reduced, a stable explosion-proof structure with small variations was obtained, and the conventional thin-wall thickness was maintained to maintain the same performance as the conventional liquid leakage resistance.
【０００８】[0008]
【実施例】以下、本発明の一実施例のアルカリ電池につ
いて図１、図２を用いて説明する。単２サイズのアルカ
リ電池において、６・６ナイロン製のガスケット１を用
い、環状薄肉型の防爆機構について、薄肉部１ｂと厚肉
部１ａとの連結部１ｃのＲ部寸法をＲ０．０１，Ｒ０．
０２，Ｒ０．０５，Ｒ０．１０，Ｃ部寸法をＣ０．０
１，Ｃ０．０２，Ｃ０．０５，Ｃ０．１０，各３０個の
薄肉部の破断圧力の測定および上記各条件のガスケット
を使用して通常の製造法にて図２のように単２のアルカ
リ電池を作製して４個の上記アルカリ電池を接続中、１
個逆接続して逆接続された電池の膨脹、破裂状態を観察
する防爆実装試験を実施した。薄肉部の厚みについては
成形加工技術上、または金型加工精度上の観点より、通
常成形加工できる薄肉厚みとしては０．３〜０．５ｍｍ
であり今回０．３ｍｍのものを準備した。Ｒ０．０１，
Ｒ０．０２，Ｒ０．０５，Ｒ０．１０、Ｃ０．０１，Ｃ
０．０２，Ｃ０．０５，Ｃ０．１０の条件で作製された
ガスケットならびにそのガスケットを使用して作製され
た電池をそれぞれ、試験品１〜８とし、その結果を（表
１）に示す。DESCRIPTION OF THE PREFERRED EMBODIMENTS An alkaline battery according to an embodiment of the present invention will be described below with reference to FIGS. In a C-size alkaline battery, a gasket 1 made of 6.6 nylon is used, and in the annular thin-wall type explosion-proof mechanism, the R portion dimensions of the connecting portion 1c between the thin portion 1b and the thick portion 1a are R0.01, R0. .
02, R0.05, R0.10, C part size is C0.0
1, C0.02, C0.05, C0.10, measurement of the breaking pressure of each of the thirty thin portions and the use of a gasket under the above-mentioned conditions by a normal production method as shown in FIG. While the batteries were being prepared and the above four alkaline batteries were connected, 1
An explosion-proof mounting test was performed to observe the expansion and rupture of the batteries connected in reverse connection. Regarding the thickness of the thin portion, from the viewpoint of molding technology, or from the viewpoint of mold processing accuracy, as a thin thickness that can be normally molded, 0.3 to 0.5 mm
In this case, a 0.3 mm one was prepared. R0.01,
R0.02, R0.05, R0.10, C0.01, C
The gaskets manufactured under the conditions of 0.02, C0.05, and C0.10 and the batteries manufactured using the gaskets were designated as test samples 1 to 8, respectively, and the results are shown in (Table 1).
【０００９】[0009]
【表１】 [Table 1]
【００１０】（表１）に示す通り、Ｒ０．０２以下，Ｃ
０．０２以下において破断圧力が低い値を示しバラツキ
も小さい値を得、防爆実装試験においても良好な結果を
得た。この結果より、薄肉部と厚肉部との連結部を完全
なエッジ形状にした場合でも良好な結果が得られること
が容易に推察できる。As shown in Table 1, R 0.02 or less, C
At 0.02 or less, the breaking pressure showed a low value and a small variation was obtained, and good results were obtained also in the explosion-proof mounting test. From these results, it can be easily inferred that good results can be obtained even when the connecting portion between the thin portion and the thick portion has a complete edge shape.
【００１１】また、薄肉部と厚肉部との連結部分のＲ部
寸法・Ｃ寸法を安定させるため、樹脂成形の金型加工方
法として、旋盤等で切削したものを１８０Ｋ番手以下の
砥石にて樹脂成形金型を研磨加工することにより、精度
よく所望するところのガスケットを成形している。In order to stabilize the R and C dimensions of the connecting portion between the thin portion and the thick portion, as a method of processing a resin molding die, a die cut with a lathe or the like is used with a grindstone of 180K or less. By polishing the resin molding die, a desired gasket is accurately formed.
【００１２】ガスケットの薄肉部１ｂと厚肉部１ａとの
連結部の片側のみＲ０．０２のＲ部寸法のものを準備し
実施例１と同様の評価を行った。受圧面側をＲ０．０２
にしたものを試験品９、ガス放出側をＲ０．０２にした
ものを試験品１０とし、結果については、それぞれ（表
１）の試験品９、１０に示す。この結果より、両面を寸
法規制した場合の効果はもとより、片側のみの寸法規制
でも効果が確認された。Only one side of the connecting portion between the thin portion 1b and the thick portion 1a of the gasket was prepared with an R portion size of R0.02, and the same evaluation as in Example 1 was performed. Pressure receiving surface side is R0.02
Specimen 9 was obtained by setting R0.02 on the gas release side, and Specimen 10 was obtained by setting the gas release side to R0.02. The results are shown in Specimens 9 and 10 in (Table 1). From these results, it was confirmed that the effect was obtained not only when the size was restricted on both surfaces but also when the size was restricted on only one side.
【００１３】[0013]
【発明の効果】以上の実施例の説明より明らかなよう
に、本発明のアルカリ電池によれば、ガスケットの薄肉
部と厚肉部との連結部分の少なくとも一方のＲ部を０．
０２Ｒ以下または面取りを０．０２Ｃ以下に寸法規制す
ることにより、十分な薄肉部厚みを確保するとともに、
バラツキが小さくしかも所望とするところの破断圧力で
あるガスケットの寸法形状を得ることにより、耐漏液
性、防爆作動性に優れた製品を提供することができるも
のである。As is apparent from the above description of the embodiment, according to the alkaline battery of the present invention, at least one R portion of the connecting portion between the thin portion and the thick portion of the gasket is set to 0.1.
By controlling the size of 02R or less or the chamfer to 0.02C or less, while ensuring a sufficient thin-walled portion thickness,
By obtaining the size and shape of the gasket which has a small variation and a desired breaking pressure, it is possible to provide a product excellent in liquid leakage resistance and explosion proof operation.
【図１】本発明の一実施例によるガスケットの断面図FIG. 1 is a cross-sectional view of a gasket according to one embodiment of the present invention.
【図２】本発明の一実施例によるアルカリ電池の断面図FIG. 2 is a cross-sectional view of an alkaline battery according to one embodiment of the present invention.
１ ガスケット １ａ ガスケット厚肉部 １ｂ ガスケット薄肉部１ｃ ガスケット連結部 ２ 集電子 ３ 底板 ４ 座金 ５ 陰極活物質 ６ 正極活物質 ７ セパレータ ８ 鉄ケース ９ キャップDESCRIPTION OF SYMBOLS 1 Gasket 1a Gasket thick part 1b Gasket thin part 1c Gasket connection part 2 Current collector 3 Bottom plate 4 Washer 5 Cathode active material 6 Positive electrode active material 7 Separator 8 Iron case 9 Cap
───────────────────────────────────────────────────── フロントページの続き (72)発明者 佐藤 公一 大阪府門真市大字門真1006番地 松下電 器産業株式会社内 (56)参考文献 実開 昭57−201766（ＪＰ，Ｕ) (58)調査した分野(Int.Cl.7，ＤＢ名) H01M 2/08 H01M 2/12 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Koichi Sato 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References Jikaichi Sho 57-201766 (JP, U) (58) Survey Field (Int.Cl. 7 , DB name) H01M 2/08 H01M 2/12
Claims (2)
スケットに、薄肉部を設けて防爆機構を有する構造であ
って、このガスケットの薄肉部と厚肉部との連結部のコ
ーナー部がＲ＝０．０２ｍｍ以下または面取りがＣ＝
０．０２ｍｍ以下であるガスケットを用いたことを特徴
とするアルカリ電池。1. A gasket for closing an opening of a case of an alkaline battery is provided with a thin portion provided with an explosion-proof mechanism, and a corner portion of a connecting portion between the thin portion and the thick portion of the gasket has R = R 0.02mm or less or chamfer is C =
An alkaline battery using a gasket of 0.02 mm or less.
くとも防爆機構作動時のガス受圧面側の連結部のコーナ
ー部がＲ＝０．０２ｍｍ以下または面取りがＣ＝０．０
２ｍｍ以下である請求項１記載のアルカリ電池。2. The gasket according to claim 1, wherein said thin portion and said thick portion have at least a corner of R = 0.02 mm or a chamfer of C = 0.02 at a corner of a connecting portion on a gas pressure receiving surface side when an explosion-proof mechanism is operated.
The alkaline battery according to claim 1, which is 2 mm or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP02791694A JP3248332B2 (en) | 1994-02-25 | 1994-02-25 | Alkaline battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP02791694A JP3248332B2 (en) | 1994-02-25 | 1994-02-25 | Alkaline battery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07240195A JPH07240195A (en) | 1995-09-12 |
| JP3248332B2 true JP3248332B2 (en) | 2002-01-21 |
Family
ID=12234214
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP02791694A Expired - Lifetime JP3248332B2 (en) | 1994-02-25 | 1994-02-25 | Alkaline battery |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3248332B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005536855A (en) * | 2002-08-28 | 2005-12-02 | エヴァレディー バッテリー カンパニー インコーポレイテッド | Seal for electrochemical battery |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5546275B2 (en) * | 2010-02-12 | 2014-07-09 | Ｆｄｋエナジー株式会社 | Alkaline battery gasket and alkaline battery |
-
1994
- 1994-02-25 JP JP02791694A patent/JP3248332B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005536855A (en) * | 2002-08-28 | 2005-12-02 | エヴァレディー バッテリー カンパニー インコーポレイテッド | Seal for electrochemical battery |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07240195A (en) | 1995-09-12 |
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