JPS6050033B2 - thin battery - Google Patents

Description

【発明の詳細な説明】 本発明は薄形電池の封口の改良に関し、封口性能の優
れた樹脂を用いて封口してなる薄形電池に係るものであ
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the sealing of a thin battery, and relates to a thin battery sealed using a resin with excellent sealing performance.

従来の薄形電池の封口材はセパレータの周縁に、酢酸
ビニルと塩化ビニルとの共重合体樹脂、あるいはポリア
ミド樹脂が用いられ、これを加熱溶融し、熱ローラーま
たは熱スタンプで塗布付着していた。Conventional sealing materials for thin batteries use vinyl acetate and vinyl chloride copolymer resin or polyamide resin around the periphery of the separator, which is heated and melted and applied using a heated roller or heat stamp. .

しかし、酢酸ビニルと塩化ビニルとの共重合体樹脂を塗
布付着したセパレータを用いて発電要素等を密封口した
電池は、樹脂の熱安定性が悪いため高温長期貯蔵中にセ
パレータと陰・陽トＪ４−四１１｜■−、曲一＋【ｉ却
＾ｎｌｌ婚ュ♂七、い ウ士ユｉ が被れ電解液が漏液
したり、また、セパレータが乾燥して電池内部抵抗が増
大し、電圧低下、容量低下を起す原因となつた。 従来
この改良として、ポリアミド系熱溶融性樹脂をセパレー
タの周縁に塗布付着させて発電要素等を密封口した電池
があつたが、熱安定性は向上したが、上記熱溶融性樹脂
の加熱溶融作業を、樹脂の酸化防止のため窒素雰囲気で
行なわねばならず、セパレータヘの塗布作業がきわめて
繁雑になつた。However, batteries that use a separator coated with a copolymer resin of vinyl acetate and vinyl chloride to seal the power generation elements, etc., have negative and positive interactions with the separator during long-term storage at high temperatures due to the poor thermal stability of the resin. J4-411｜■-, song 1 + [i ＾ nll marriage ♂ 7, い う し ゆ い] may be covered and the electrolyte may leak, or the separator may dry and the internal resistance of the battery may increase. This caused voltage drop and capacity drop. Conventionally, as an improvement to this, a battery was created in which a polyamide-based heat-melt resin was coated on the periphery of the separator to seal the power generation element, etc., but although the thermal stability was improved, the work of heating and melting the heat-melting resin was improved. This process had to be carried out in a nitrogen atmosphere to prevent oxidation of the resin, making the process of coating the separator extremely complicated.

また耐熱性が向上したため高温長期貯蔵中の電解液の漏
液、セパレータの乾燥は良好となつたが、電池内で貯蔵
中陰極体である亜鉛のわすかな自己腐食による水素ガス
が発生すると、電池はふくれ、ガスによる電気絶縁空間
が形成され、内部抵抗が増大し放電電圧が低下したり、
陰・陽極体間で接触不良が生じ、放電性能が極端に劣化
する欠点があつた。さらに、溶解した樹脂が高粘度であ
るため、不織布、紙等のセパレータに含浸させるのが困
難で不織布の周縁の繊維の細部にまで・行きわたらず、
このようなセパレータを電池に組込むと電解液が浸透し
てきて、樹脂が到達していない細部を通り抜け、電池外
へ漏液する欠点があつた。 本発明はテレフタル酸と飽
和多価アルコールと・から合成した飽和ポリエステル樹
脂をセパレータの周縁に含浸して電池を封口することに
より、貯蔵性能を大幅に向上せしめることを目的とする
。Also, due to improved heat resistance, electrolyte leakage and separator drying during high-temperature long-term storage are now better; however, when hydrogen gas is generated due to slight self-corrosion of zinc, which is the cathode body, during storage, the battery The gas bulges, forming an electrically insulating space due to the gas, increasing internal resistance and lowering the discharge voltage.
The drawback was that poor contact occurred between the cathode and anode bodies, resulting in extremely poor discharge performance. Furthermore, because the dissolved resin has a high viscosity, it is difficult to impregnate separators such as nonwoven fabrics and paper, and it is difficult to penetrate into the fine details of the fibers around the periphery of the nonwoven fabric.
When such a separator is incorporated into a battery, there is a drawback that the electrolyte permeates through the parts that the resin has not reached and leaks out of the battery. The object of the present invention is to significantly improve storage performance by impregnating the periphery of a separator with a saturated polyester resin synthesized from terephthalic acid and a saturated polyhydric alcohol to seal the battery.

本発明の実施例の薄形電池を図をもつて説明する。図に
おいて、１は陰極集電体で２は陽極集電体である。A thin battery according to an embodiment of the present invention will be explained with reference to the drawings. In the figure, 1 is a cathode current collector and 2 is an anode current collector.

この両極集電体１，２は例えばアルミニウム、ニッケル
、スチール、ステレススチール等の耐腐食性の金属箔３
からなり、内面には炭素質に塩化ビニル樹脂などの結着
材を添加し塗布、吹付け等により炭素膜４が被着されて
いる。５は例えば亜鉛箔、亜鉛粉など陰極活物質からな
る薄層状の陰極体で陰極集電体１の炭素膜４に密着して
いる。These bipolar current collectors 1 and 2 are made of corrosion-resistant metal foil 3 made of aluminum, nickel, steel, stainless steel, etc.
A carbon film 4 is coated on the inner surface by coating, spraying, etc., by adding a binder such as vinyl chloride resin to carbonaceous material. Reference numeral 5 denotes a thin layer cathode body made of a cathode active material such as zinc foil or zinc powder, which is in close contact with the carbon film 4 of the cathode current collector 1 .

６は例えば活物質である二酸化マンガン粉を主体とし、
これに電導体であるアセチレンブラック、結着材である
ポリビニルアルコールまたポリアクリル酸を添加混合し
た陽極体で、陽極集電体２の炭素膜４に、例えばスクリ
ーン印刷やローラ塗着などにより薄層状に密着している
。この陰極体５と陽極体６との間にはポリビニルアルコ
ール繊維の不織布からなるセパレータ７が挾着されてい
る。セパレータ７には、例えば塩化亜鉛水溶液または塩
化亜鉛と塩化アンモニウムの混合水溶液からなる電解液
を含有している。またセパレータ７の周縁にはテレフタ
ル酸と飽和多価アルコールとから合成された飽和ポリエ
ステル樹脂８が含−浸され、電解液がセパレータ７の周
縁より漏液しないようにしている。９は合成樹脂からな
るフィルム状の外装体で、セパレータ７を介して陰・陽
極体５，６を配置し、両極集電体１，２で挾持してなる
電池発電要素全体を、陰極端子部１０と陽．極端子部１
１を除き重ねて外装するとともに、封口部１２を加熱圧
着して、セパレータ７に含浸されている飽和ポリエステ
ル樹脂８で発電要素を熱圧着し密封固定し封口して電池
を完成している。6 mainly consists of manganese dioxide powder as an active material,
Acetylene black, which is a conductor, and polyvinyl alcohol or polyacrylic acid, which are binders, are added to this anode body, and a thin layer is formed on the carbon film 4 of the anode current collector 2 by, for example, screen printing or roller coating. Closely attached to. A separator 7 made of a nonwoven fabric of polyvinyl alcohol fibers is clamped between the cathode body 5 and the anode body 6. The separator 7 contains an electrolytic solution consisting of, for example, a zinc chloride aqueous solution or a mixed aqueous solution of zinc chloride and ammonium chloride. Further, the periphery of the separator 7 is impregnated with a saturated polyester resin 8 synthesized from terephthalic acid and saturated polyhydric alcohol to prevent electrolyte from leaking from the periphery of the separator 7. Reference numeral 9 denotes a film-like exterior body made of synthetic resin, in which the cathode and anode bodies 5 and 6 are arranged with a separator 7 in between, and the entire battery power generating element formed by sandwiching them between the bipolar current collectors 1 and 2 is connected to the cathode terminal section. 10 and yang. Pole terminal part 1
Except for 1, the battery is stacked and packaged, and the sealing part 12 is bonded under heat and pressure, and the power generation element is bonded under heat and pressure using the saturated polyester resin 8 impregnated in the separator 7, and the battery is sealed and sealed.

陰極端子部１０と陽極端子部１１は外装体９の１部に両
極集電体１，２の金属箔３を露出することにより設けら
れている。本発明の実施例電池はテレフタル酸と飽和多
価アルコールとから合成した飽和ポリエステル樹脂８を
溶剤に溶解した溶液であるため、不織布のセくパレータ
７の周縁の細部まで含浸され、溶剤を加熱蒸発逸散せし
めるもので、セパレータ７の繊維の細部まて浸透し、該
樹脂８は繊維および炭素膜４に対して密着性が強く、電
解液等に対する耐薬品性、高温貯蔵での耐熱性に優れて
いる。The cathode terminal section 10 and the anode terminal section 11 are provided by exposing the metal foils 3 of the bipolar current collectors 1 and 2 to a part of the exterior body 9. Since the example battery of the present invention is a solution in which a saturated polyester resin 8 synthesized from terephthalic acid and a saturated polyhydric alcohol is dissolved in a solvent, even the fine details of the periphery of the nonwoven fabric separator 7 are impregnated, and the solvent is heated and evaporated. The resin 8 penetrates into the fine details of the fibers of the separator 7, and the resin 8 has strong adhesion to the fibers and carbon membrane 4, and has excellent chemical resistance to electrolytes and heat resistance during high-temperature storage. ing.

また、飽和ポリエステル樹脂８の合成は、ポリアミド系
熱溶融性樹脂のように窒素雰囲気で行なう必要がなく、
室内の空気中で開放的に合成でき、作業性の面で大巾に
改良できる。さらに、セパレータ周縁部の細部まで飽和
ポリエステル樹脂８が含浸されるので、密封効果が優れ
、微量の水分の出入がない。水分の出入があると電解液
の組成が変化し、放電性能を劣化させるが、本発明は水
分の出ノ入がないので、放電性能を高レベルで維持する
ことができる。さらにまた、該樹脂８は内部可塑化して
優れた粘着性、感圧性、熱溶融性を付加することができ
る。Furthermore, the synthesis of the saturated polyester resin 8 does not need to be carried out in a nitrogen atmosphere unlike polyamide thermofusible resins.
It can be synthesized openly in indoor air, and it can greatly improve workability. Furthermore, since the saturated polyester resin 8 is impregnated to the smallest detail of the separator periphery, the sealing effect is excellent and there is no trace amount of moisture entering or exiting. If water enters or exits, the composition of the electrolyte changes and the discharge performance deteriorates, but in the present invention, since there is no water in or out, the discharge performance can be maintained at a high level. Furthermore, the resin 8 can be internally plasticized to provide excellent adhesiveness, pressure sensitivity, and heat meltability.

この場合、軟質塩化ビニルのように可塑剤、例えばジオ
クチルフタレート（Ｄ．Ｏ．Ｐ）を単に混合する外部可
塑化のようなものではなく、該樹脂８にテレフタル酸と
飽和多価アルコールとの重合反応において、例えばアヂ
ピン酸等の薬剤を添加し、化学反応の結果として可塑性
を有する可塑化飽和ポリエステル樹脂８を製造するもの
である。このように内部可塑化された樹脂８″として、
東洋紡績製商品名バイロン３００がある。このため、高
温貯蔵での可塑剤の移行による接着障害が起らず、軟く
伸びがよく粘着型の接着機構を有するため、この可塑化
樹脂８″で封口した薄形電池は、高温貯蔵中等内部にガ
スが発生しても、除々にガスだけを逸散せしめることが
できる。次に、本発明電池と従来電池とを比較する。In this case, instead of external plasticization in which a plasticizer such as dioctyl phthalate (D.O.P.) is simply mixed as in the case of soft vinyl chloride, the resin 8 is polymerized with terephthalic acid and a saturated polyhydric alcohol. In the reaction, a chemical such as adipic acid is added, and a plasticized saturated polyester resin 8 having plasticity is produced as a result of the chemical reaction. As the internally plasticized resin 8″,
There is a product name Byron 300 manufactured by Toyobo. Therefore, there is no adhesion failure due to plasticizer migration during high-temperature storage, and the thin battery sealed with this plasticized resin 8" has a soft, stretchy, and sticky adhesive mechanism. Even if gas is generated inside, only the gas can be gradually dissipated.Next, the battery of the present invention will be compared with a conventional battery.

まず、化学反応により内部可塑化したフタル酸とエチレ
ングリコールとアヂピン酸とを合成した飽和ポリエステ
ル樹脂８″を溶剤に３０％混合溶解して、不織布のセパ
レータ７の周縁両面にローラーまたはスタンプで含浸し
て、８０℃に１時間乾燥し可塑化樹脂８″層を１０〜３
０ＰＴｒ！．の厚さにする。このセパレータ７を介して
陰・陽極体５，６を配置し、陰・陽極集電体１，２で挾
持して周縁を合せて重ね、１２０℃で５ｋ９／Ｃｌｔで
０．醗間封口部１２を加熱圧着して密封口し、大きさ４
０ｗｎ×７ｈ、厚さ０．７Ｔｆｎの１．５Ｖの薄形電池
を１（１）個組立て、本発明品〔Ａ〕とした。また、内
部可塑化していない飽和ポリエステル樹脂８を同様に用
い１（４）個組立て、本発明品〔Ｂ〕とした。さらに、
従来品として酢酸ビニルとエチレンの共重合熱溶融性樹
脂を１３０℃で加熱溶融し、熱口ーラーで不織布のセパ
レータに塗布して、同型の薄形電池を１（１）個組立て
従来品〔Ｃ〕とし、またさらに、ポリアミド樹脂を用い
同様に１叩個組立て、従来品〔Ｄ〕とした。First, 30% of a saturated polyester resin 8'' synthesized from phthalic acid, ethylene glycol, and adipic acid that has been internally plasticized through a chemical reaction is mixed and dissolved in a solvent, and the mixture is impregnated onto both sides of the periphery of the nonwoven fabric separator 7 using a roller or a stamp. and dried at 80℃ for 1 hour to form 10 to 3 8" layers of plasticized resin.
0PTr! ．． Make it as thick as possible. The cathode and anode bodies 5 and 6 are arranged with the separator 7 in between, sandwiched between the cathode and anode current collectors 1 and 2, and overlapped with their peripheral edges together, and heated to 5k9/Clt at 120°C with a temperature of 0. The gap sealing part 12 is sealed by heating and pressing, and the size is 4.
One (1) 1.5V thin battery having a size of 0wn×7h and a thickness of 0.7Tfn was assembled and designated as a product of the present invention [A]. In addition, 1 (4) pieces of saturated polyester resin 8 which was not internally plasticized were assembled in the same manner to obtain a product of the present invention [B]. moreover,
Conventional product [C ], and a conventional product [D] was made by assembling one piece using polyamide resin in the same manner.

これら大きさ４０ｗ０ｎ×７０Ｔｆ０ｎ１厚さ０．７コ
の薄形電池である本発明品〔Ａ〕、〔Ｂ〕と従来品〔Ｃ
〕、＊３〔Ｄ〕との各５０個を組立て、１週間後に開路
電圧、５００Ωの閉路電圧、電池厚さ、５００Ω連続放
電の持続時間を測定し、表１にまとめた。These inventive products [A] and [B], which are thin batteries with a size of 40w0n x 70Tf0n1 and a thickness of 0.7, and a conventional product [C
], *3 [D] were assembled, and one week later, the open circuit voltage, 500 Ω closed circuit voltage, battery thickness, and duration of 500 Ω continuous discharge were measured, and the results are summarized in Table 1.

また、４５℃で３ケ月間各５睡貯蔵し、開路電圧、５０
０Ω負荷の閉路電圧、５００Ωの放電持続時間、電池厚
さ、漏液数を測定し、表２にまとめた。表１，２のこと
く、本発明品〔Ａ〕、〔Ｂ〕は組立１週間後ては各性能
がわすかに優れているにすぎないが、高温貯蔵後では、
開路電圧、閉路電圧、放電持続時間、電池厚さ、漏液個
数共に大幅に向上している。In addition, after storage at 45℃ for 3 months for 5 days each, the open circuit voltage was 50℃.
The closed circuit voltage at 0Ω load, the discharge duration at 500Ω, the battery thickness, and the number of leaks were measured and summarized in Table 2. As shown in Tables 1 and 2, the products [A] and [B] of the present invention are only slightly superior in performance after one week of assembly, but after high-temperature storage,
Open circuit voltage, closed circuit voltage, discharge duration, battery thickness, and number of leaks have all been significantly improved.

以上のごとく、本発明のセパレータの周縁に含浸されて
いるテレフタル酸と飽和多価アルコールとから合成した
飽和ポリエステル樹脂で電池周縁の封口部を接着封口し
てなる薄形電池は、貯蔵性能と漏液性能とを大幅に向上
し、その工業的価値は大なるものである。As described above, a thin battery in which the periphery of the battery is sealed with a saturated polyester resin synthesized from terephthalic acid and saturated polyhydric alcohol, which is impregnated around the periphery of the separator of the present invention, has improved storage performance and leakage. This greatly improves liquid performance and has great industrial value.

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

図は本発明の実施例の薄形電池の断面図てある。 ７・・・・・・セパレータ、８・・・・・・飽和ポリエ
ステル樹脂。The figure is a sectional view of a thin battery according to an embodiment of the present invention. 7... Separator, 8... Saturated polyester resin.

Claims (1)

【特許請求の範囲】 １ セパレータを介して陰極体と陽極体とからなる電池
発電要素を、陰極集電体と陽極集電体とで挾持し、かつ
、陰極端子部と陽極端子部を除いて外装体で被覆した薄
形電池において、前記セパレータの周縁に含浸されたテ
レフタル酸と飽和多価アルコールとから合成した飽和ポ
リエステル樹脂で、電池周縁の封口部を封口してなるこ
とを特徴とする薄形電池。 ２ 該飽和多価アルコールが、エチレングリコールであ
ることを特徴とする特許請求の範囲第１項記載の薄形電
池。[Claims] 1. A battery power generation element consisting of a cathode body and an anode body is sandwiched between a cathode current collector and an anode current collector through a separator, and the cathode terminal portion and the anode terminal portion are excluded. A thin battery covered with an exterior body, characterized in that the peripheral edge of the battery is sealed with a saturated polyester resin synthesized from terephthalic acid and saturated polyhydric alcohol, which is impregnated around the edge of the separator. shaped battery. 2. The thin battery according to claim 1, wherein the saturated polyhydric alcohol is ethylene glycol.