JP2004303625A

JP2004303625A - Battery pack and manufacturing method thereof

Info

Publication number: JP2004303625A
Application number: JP2003096708A
Authority: JP
Inventors: Tatsuya Kamata; 龍也鎌田
Original assignee: Hitachi Maxell Ltd
Current assignee: Maxell Holdings Ltd
Priority date: 2003-03-31
Filing date: 2003-03-31
Publication date: 2004-10-28

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery pack suitable for small-sized electric equipment which is required to be downsized and thinned, wherein the battery back with unit batteries and their electrical components integrated by a resin mold can be formed without being impaired in its external appearance, while maintaining a symmetry property of an external appearance shape, so that no waste is incurred in a battery housing space. <P>SOLUTION: A unit battery 1 with a low-profile square box shape and the electrical components disposed on a peripheral surface of the battery 1 are fixed by a resin mold 2. The resin mold 2 integrates the electrical components with the battery 1 by covering the front and rear surfaces and left and right side surfaces of the battery 1. The resin mold 2 is formed by being divided into a primary molding part 2a and a secondary molding part 2b by a two-color molding method. A primary molding is performed by fitting the battery 1 and the electrical components fixed to its peripheral surface into a first mold 30 to fix them and injecting resin into a second mold 32 jointed to the first mold 30. A secondary molding is performed by jointing the second mold 32 separated from the first mold 30 to a third mold 34 and injecting the resin into the third mold 34. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、素電池と、素電池に付属する電装品とが樹脂モールドによって一体化してあるパック電池とその製造方法に関する。
【０００２】
【従来の技術】
素電池と、素電池に付属する電装品とを樹脂モールドによって一体化することは公知である。この種のパック電池には、素電池とその電装品の全てを樹脂モールド内に埋設し、出力端子部分のみを露出させる全被覆型の電池パック（特許文献１参照）と、モジュール化された保護回路や出力端子、あるいはリード線などの電装品のみを樹脂モールドで覆う部分被覆型のパック電池（特許文献２参照）とがある。後者のパック電池では、出力端子が樹脂モールドで被覆されるので、保護回路から出力リード線を導出し、その導出端にコネクタを設けている。
【０００３】
【特許文献１】
特開２００２−１３４０７７号公報（段落番号００２１〜２２、図３）
【特許文献２】
特開２０００−３１５４８３号公報（楽項番号００３４、図３）
【０００４】
【発明が解決しようとする課題】
上記のようなパック電池によれば、素電池とその電装品の全体を樹脂モールドで被覆し、あるいはモジュール化された保護回路や出力端子などの電装品を樹脂モールドで素電池と一体化するので、電装品の組み立てに要する手間を省いて生産性を向上できる。さらに、少なくとも保護回路や出力端子などの重要な構成部品が樹脂モールドで覆われるので、絶縁性を向上できるうえ、パック電池の分解を困難化して安全性を向上できる。高度の防塵性や防滴性を発揮して信頼性を向上できる利点もある。しかし、全被覆型にしても部分被覆型にしても問題がある。
【０００５】
全被覆型のパック電池においては、成形技術上の問題がある。素電池に電装品が仮組みしてあるブランクパックの外面全体を樹脂モールドで覆うには、ブランクパックの周面の全体を、成形金型の内面壁から離れた状態で支えて位置決めする必要がある。多くの場合には、成形金型の内面に設けた複数個の位置決めピンでブランクパックを固定支持して、ブランクパックが金型内に注入される溶融樹脂によって移動されるのを防いでいる。
【０００６】
例えば、薄型のパック電池に多く見られる薄形角箱状の素電池を位置決めする場合には、少なくとも前後面と、左右側面、および下面の、５個の周面を固定支持する必要があるが、このように成形空間内にいくつもの位置決めピンを設けると、得られたパック電池の周面に、位置決めピンを抜き取ったあとの抜穴が、位置決めピンの数だけ形成されるのを避けられない。リード線が先の抜穴に面している場合には、パック電池の絶縁性が損なわれやすい。いくつもの穴があいているパック電池は、この種の電池が携帯電話などの目に付きやすい小形電気機器に適用されることが多いこともあって、外観上の体裁に問題がある。
【０００７】
その点、部分被覆型のパック電池は、必要部分だけを樹脂モールドで覆うので、成形技術上は、左程の問題もなくパック電池を形成できる。位置決めピンの抜き穴がモールド部分の表面に形成されることもない。しかし、部分被覆型のパック電池は、樹脂モールド部分が素電池の周面一部に局部的に設けられるため、パック電池の外観形状の対称性が損われる点に問題がある。例えば、パック電池を携帯電話などの小形電気機器に適用する場合には、樹脂モールド部分の厚み寸法や幅寸法に等しい電池収容空間を確保する必要があり、小形化と薄型化がさらに追求される小形電気機器において、機器内にデッドスペースを生じる不利がある。正極端子と負極端子を樹脂モールド部分に集約配置する必要があり、素電池の構造が特殊化する難点もある。全被覆型のパック電池に比べて絶縁性が劣り、分解され易い不利もある。
【０００８】
前後および左右の対称性を維持するために、素電池の４周面、例えば前後・左右を樹脂モールドで覆って、外観形状の対称性に問題がない、半被覆型のパック電池を形成することは不可能ではないが、その場合には、素電池の４周面を位置決めピンで位置決めする必要があり、先に説明した全被覆型のパック電池と同様に、位置決めピンの問題を生じ、得られる電池パックの外観に問題が残る。
【０００９】
本発明の目的は、モールド部分の外観上の体裁を向上できるうえ、外観形状の対称性を維持でき、従って、電池収容空間に無駄が無く、小形化と薄型化が要求される小形電気機器に好適なパック電池を提供することにある。本発明の目的は、素電池と、その電装品とが樹脂モールドによって一体化してある全被覆型の電池パック、あるいは素電池の少なくとも４周囲が樹脂モールドで覆ってある半被覆型の電池パックを、それぞれ外観上の体裁を損なうことなく形成できるパック電池の製造方法を提供することにある。
【００１０】
【課題を解決するための手段】
本発明のパック電池は、薄型角箱状の素電池１と、素電池１の周面に配置される素電池１の電装品とが、これらの外面を覆う樹脂モールド２で固定してある。素電池１の少なくとも２対の対向辺部を樹脂モールド２で覆う。樹脂モールド２は、１次成形部分２ａと２次成形部分２ｂとで構成する（請求項１）。
【００１１】
１次成形部分２ａと２次成形部分２ｂとは、素電池１の厚み方向中途部を通る平面で分割する（請求項２）。
【００１２】
１次成形部分２ａと２次成形部分２ｂとは、素電池１の長手方向中途部を通る平面で分割する（請求項３）。
【００１３】
電装品の配置面を含む素電池１の２対の対向周側面を、樹脂モールド２で覆って半被覆型のパック電池を構成する（請求項４）。
【００１４】
素電池１と、素電池１の電装品の外面全体を、樹脂モールド２で覆って全被覆型のパック電池を構成する（請求項５）。
【００１５】
電装品は、素電池１の前後周面の一方に配置される第１保護部品７と、素電池１の前後周面の他方に配置される第２保護部品８と、素電池１の左右周面のいずれか一方に配置されて、第１保護部品７と第２保護部品８とを接続するリード線１０と、第１保護部品７の外面に設けられる正負の出力端子１４・１５とを含む（請求項６）。
【００１６】
第１保護部品７の外面に出力端子１４・１５を突設する。第１保護部品７、および出力端子１４・１５の外面に、溶融樹脂の流入を防ぐ保護カバー１９を配置する。保護カバー１９は、樹脂モールド２で固定する（請求項７）。
【００１７】
本発明のパック電池の製造方法においては、図４に示すように、薄型角箱状の素電池１の周面に、素電池１に付属する電装品を組み付けてブランクパックＰを形成する組立工程と、ブランクパックＰを第１金型３０の装填空間３１に装填して、ブランクパックＰを第１金型３０で位置決め固定したのち、第２金型３２を第１金型３０に接合固定する前段準備工程と、第２金型３２の成形空間３３に露出する素電池１、および素電池１の電装品の周面に溶融樹脂を充填して、樹脂モールド２の１次成形部分２ａを形成する１次成形工程と、素電池１と、素電池１の電装品、および１次成形部分２ａを含んだ状態で第２金型３２を第１金型３０から分離したのち、第２金型３２を第３金型３４に接合固定する後段準備工程と、第３金型３４の成形空間３５に露出する素電池１、および素電池１の電装品の周面に溶融樹脂を充填して、樹脂モールド２の２次成形部分２ｂを形成する２次成形工程とを経て、素電池１の少なくとも２対の対向辺部を覆う樹脂モールド２を形成することを特徴とする（請求項８）。
【００１８】
１次成形部分２ａと２次成形部分２ｂとの境界面は、素電池１の厚み方向中途部を通る平面上に設定する（請求項９）。
【００１９】
１次成形部分２ａと２次成形部分２ｂとの境界面は、素電池１の長手方向中途部を通る平面上に設定する（請求項１０）。
【００２０】
【発明の作用効果】
本発明のパック電池においては、素電池１の少なくとも４周面を樹脂モールド２で覆って、電装品を素電池１と一体化する場合に、樹脂モールド２を１次成形部分２ａと２次成形部分２ｂとに分けて構成するので、１次成形部分２ａを成形する際に、素電池１や素電池１に組み付けられた電装品の非成形部分を第１金型３０に嵌め込んで固定できる。つまり、成形用の金型の片方で、素電池１および電装品を固定保持した状態で１次成形部分２ａを成形できる。このように、素電池１および電装品を成形用金型で直接固定保持すると、金型内部に素電池１および電装品を位置決めするためのピンや突起などを設ける必要がないので、樹脂モールド２にピンや突起の抜き跡が形成されるのを解消でき、外観上の体裁に優れた樹脂モールド２を形成できるうえ、外観形状の対称性を維持できる。従って、電池収容空間に無駄が無く、小形化と薄型化が要求される小形電気機器に好適なパック電池が得られる。２次成形部分２ｂを成形するときは、１次成形部分２ａが金型に固定保持されているので、問題なく２次成形部分２ｂを形成できる（請求項１）。
【００２１】
１次成形部分２ａと２次成形部分２ｂを、素電池１の厚み方向中途部を通る平面で分割したパック電池によれば、樹脂モールド２を成形する各金型３０・３２・３４の成形空間３１・３３・３５を浅くすることができるので、離型を簡単に行うことができる。電装品が素電池１に組み立ててあるブランクパックＰを金型に装填する際の作業を、簡便に行える利点もある（請求項２）。
【００２２】
１次成形部分２ａと２次成形部分２ｂとを、素電池１の長手方向中途部を通る平面で分割したパック電池によれば、両成形部分２ａ・２ｂの境界線２２を最小限化できるので、境界線２２が目立つのを極力避けて、外観上体裁のよいパック電池が得られる。１次成形部分２ａおよび２次成形部分２ｂと素電池１との接触面積をほぼ均等化できるので、素電池１の周囲における樹脂モールド２の特性、例えば、絶縁性、防塵性、防滴性などの特性を均一化できる（請求項３）。
【００２３】
電装品の配置面を含む素電池１の２対の対向周側面を樹脂モールド２で覆った、半被覆型のパック電池によれば、外観形状の対称性を損うことなくパック電池を構成できるので、部分的に分厚い樹脂モールドが形成される部分被覆型のパック電池に比べて、例えば、パック電池を携帯電話などの小形電気機器に適用する場合の電池収容空間を小さくできる。素電池１の４周面を樹脂モールド２で覆うので、部分被覆型のパック電池において不可欠な、正極端子６と負極端子を樹脂モールド部分に集約配置する必要がなく、従って従来のままの製造設備で素電池１を製造すればよい点で有利である（請求項４）。
【００２４】
素電池１と素電池１の電装品の外面全体を、樹脂モールド２で覆った全被覆型のパック電池によれば、電装品はもちろん、素電池１の外面全体を樹脂モールド２で被覆して絶縁性を向上できるうえ、パック電池の分解を困難化して安全性を向上できる。絶縁性、防塵性、防滴性などの特性も向上できる（請求項５）。
【００２５】
素電池１の前後周面に配置される第１保護部品７、および第２保護部品８と、両保護部品７・８を接続するリード線１０と、正負の出力端子１４・１５とを含んで電装品を構成し、これら電装品を素電池１とともに樹脂モールド２で一体化すると、パック電池自体に保護機能を付加して、異常時の安全性を向上でき、その分だけパック電池の信頼性を向上できる（請求項６）。
【００２６】
第１保護部品７の外面に溶融樹脂の流入を防ぐ保護カバー１９を配置したパック電池によれば、第１保護部品７の外面に設けた正負の出力端子１４・１５が、成形時に溶融樹脂で覆われるのを確実に防止できるうえ、保護カバー１９によって素電池１を補強し、パック電池の構造強度を向上できる。保護カバー１９は、他物が正負の出力端子１４・１５に同時に接触して短絡するのを防ぐことにも役立っている。正負の出力端子１４・１５が、保護カバー１９に設けた窓２０・２１の開口面より内側に位置させてあるからである（請求項７）。
【００２７】
本発明のパック電池の製造方法においては、素電池１に電装品を組み付けてブランクパックＰを形成したのち、ブランクパックＰを第１金型３０の装填空間３１に装填して位置決め固定し、第１金型３０に接合した第２金型３２内に溶融樹脂を充填して、樹脂モールド２の１次成形部分２ａを形成した。引き続き、第２金型３２を第３金型３４に換装して、第３金型３４の成形空間３５に溶融樹脂を充填して、樹脂モールド２の２次成形部分２ｂを形成することにより、少なくとも４周辺部が樹脂モールド２で覆われるパック電池を形成するようにした。従って本発明のパック電池の製造方法においては、従来の射出成形法で樹脂モールドを形成する場合に不可欠であった位置決めピンを、各金型３０・３２・３４の内部に設ける必要がなく、外観上の体裁を向上できる半被覆型、あるいは全被覆型のパック電池を量産できる（請求項８）。
【００２８】
１次成形部分２ａと２次成形部分２ｂとの境界面を、素電池１の厚み方向中途部を通る平面上に設定して樹脂モールド２を成形すると、樹脂モールド２を成形する各金型３０・３２・３４の成形空間３１・３３・３５を浅くすることができるので、離型を簡単に行うことができるうえ、ブランクパックＰを金型に装填する際の作業を速やかに、しかも簡便に行える（請求項９）。
【００２９】
１次成形部分２ａと２次成形部分２ｂとの境界面を、素電池１の長手方向中途部を通る平面上に設定して樹脂モールド２を成形すると、両成形部分２ａ・２ｂの境界線２２を最小限化できるので、外観上体裁のよいパック電池が得られる。１次成形部分２ａおよび２次成形部分２ｂと、素電池１との接触面積をほぼ均等化できるので、素電池１の周囲における樹脂モールド２の特性、例えば、絶縁性、防塵性、防滴性などの特性を均一化できる（請求項１０）。
【００３０】
【実施例】
（実施例１）図１ないし図１０は本発明に係るパック電池の実施例１を示す。図２においてパック電池は、薄型角箱状の素電池１と、素電池１の周面に配置される電装品と、素電池１の上下面を除く外周面を覆う樹脂モールド２とで、半被覆型のパック電池として構成してある。
【００３１】
素電池１は、外装缶４の内部に電極体と電解液とを封入した充放電が可能な２次電池、例えばリチウムイオン電池からなり、外装缶４の前面を塞ぐ封口板５の中央に正極端子６を備えている。外装缶４はニッケル板やアルミニウム板を深絞り加工して形成してあり、それ自体が負極側の出力端子を兼ねている。電極体はＬｉＣｏＯ_２を活物質とする正極シートと、黒鉛を活物質とする負極シートとを、セパレーターを間にして渦巻状に巻回し、全体を偏平に押潰し変形して形成してある。
【００３２】
図２において電装品は、素電池１の前面側に配置される保護回路モジュール（第１保護部品）７と、素電池１の後面側に配置されるポリスイッチ（第２保護部品）８と、これら両者７・８、および先の正極端子６と保護回路モジュール７とをそれぞれ接続する長短２種の導電シート（リード線）９・１０とで構成する。
【００３３】
保護回路モジュール７は、素電池１の充放電電流を制御する制御回路が埋設してある四角棒状のプラスチック成形品からなり、両端のそれぞれに帯状の接続リード１２・１３が導出してある。先の制御回路を設けることにより、素電池１の過放電や過充電を防止できる。保護回路モジュール７の前面には、正極側の出力端子１４と、負極側の出力端子１５とが突設してある。ポリスイッチ８は、素電池１の温度が設定値を越える場合に、素電池１の電流を遮断するために設けてあり、その一端に接続リード１６が固定してある。保護回路モジュール７およびポリスイッチ８の上下厚み寸法は、素電池１の厚み寸法より僅かに小さく設定してある。導電シート９・１０、および各接続リード１２・１３・１６は、それぞれ銅、あるいはアルミニウムなどの導電性金属の薄シートを帯状に切断して形成してあり、その上下幅寸法は保護回路モジュール７の上下厚み寸法より小さく設定してある。
【００３４】
上記の電装品を素電池１に組み付け、さらに保護回路モジュール７の前面に保護カバー１９を装着固定することにより、図３に示すブランクパックＰが得られる。詳しくは、保護回路モジュール７の左右両端の接続リード１２・１３に、それぞれ短い導電シート９と長い導電シート１０をスポット溶接し、さらに長い導電シート１０の後端にポリスイッチ８の接続リード１６をスポット溶接して、電装品をひとつながりにする。次に導電シート９を正極端子６、および封口板５に絶縁性の両面テープを介して貼り付けたのち、導電シート９を正極端子６にスポット溶接する。同様に、導電シート１０を絶縁性の両面テープを介して素電池１の片側側面に貼り付け、さらにポリスイッチ８を素電池１の後面に絶縁性の両面テープを介して貼り付け、その貼着面を外装缶４にスポット溶接する。
【００３５】
図２に示すように、保護カバー１９は帯板状のプラスチック成形品からなり、その板面に保護回路モジュール７の正負の出力端子１４・１５に対応する窓２０・２１が開口してある。正負の出力端子１４・１５が各窓２０・２１に嵌り込む状態で、保護カバー１９を保護回路モジュール７の前面に貼り付けることによりブランクパックＰを完成できる。このブランクパックＰを射出成形機によって、後述する要領でインサート成形することにより、素電池１と電装品の前後面と左右面とを樹脂モールド２で覆うことができる。
【００３６】
樹脂モールド２は以下の手順で形成する。
図４（ａ）に示すように、素電池１の周面に電装品を組み付けてブランクパックＰを形成する組立工程と、
図４（ｂ）に示すように、ブランクパックＰを第１金型３０の装填空間（成形空間）３１に装填して、ブランクパックＰを第１金型（固定金型）３０で位置決め固定したのち、第２金型（可動金型）３２を第１金型３０に接合固定する前段準備工程と、
図４（ｃ）に示すように、第２金型３２の成形空間３３に露出する素電池１、および電装品の周面に溶融樹脂を充填して、樹脂モールド２の１次成形部分２ａを形成する１次成形工程と、
図４（ｄ）に示すように、素電池１と電装品、および１次成形部分２ａを含んだ状態で第２金型３２を第１金型３０から分離したのち、第２金型３２を第３金型（固定金型）３４に接合固定する後段準備工程と、
図４（ｅ）に示すように、第３金型３４の成形空間３５に露出する素電池１、および電装品の周面に溶融樹脂を充填して、樹脂モールド２の２次成形部分２ｂを形成する２次成形工程とを経て、
つまり２色成形法によって素電池１の前後、および左右側面を覆う樹脂モールド２を形成する。
【００３７】
前段準備工程において、ブランクパックＰを第１金型３０の装填空間３１に装填した状態においては、図５に示すように、保護カバー１９の前面と素電池１の外装缶４の缶底隅部とが、装填空間３１の前後壁で受け止められ、導電シート１０と素電池１の側面とが、装填空間３１の左右壁で受け止められている。つまり、ブランクパックＰは、位置決めピンを用いる必要も無く、第１金型３０によって位置決めされ、遊動不能に固定保持される。この装填状態において、素電池１および電装品は、上下寸法の半分だけが装填空間３１内に入り込んでいる。従って、第２金型３２を第１金型３０接合固定した状態では、図６および図７に示すように素電池１および電装品は、上下寸法の半分だけが成形空間３３内に入り込み、素電池１の上下面が第１第２の両金型３０・３２で挟み保持される。
【００３８】
上記のように、ブランクパックＰを第１金型３０で固定保持し、さらに素電池１の上下面を第１第２の両金型３０・３２で挟み保持すると、１次成形工程において第２金型３２の成形空間３３に溶融樹脂が注入されても、ブランクパックＰが溶融樹脂の圧力や流動作用によって動かされることは無く、常に一定形状の１次成形部分２ａを形成できる。１次成形時、および２次成形時に溶融樹脂が正負の出力端子１４・１５の外面に流れ込むのを防ぐために、保護カバー１９を保護回路モジュール７の外面に設けている。素電池１の前後面と、第１金型３０の装填空間３１の前面との間には、何箇所かの隙間が形成されるが、１次成形時にはこれらの隙間にも溶融樹脂が入り込む。溶融樹脂の注入は第１金型３０の側から行ってもよいし、第２金型３２の側から行ってもよい。
【００３９】
図８に示すように、１次成形工程で得られた成形ブランクは、素電池１より僅かに広幅の１次成形部分２ａを有し、保護回路モジュール７の外面と、ポリスイッチ８の外面とがモールドされた樹脂で覆われている。１次成形部分２ａを点描で示している。
【００４０】
後段準備工程においては、第２金型３２を第１金型３０から分離して、第３金型３４に接合するが、このとき第２金型３２は図示していない軸周りに回転して第３金型３４と対向し、それまで第３金型３４と対向し、パック電池が離型された別の第２金型が第１金型３０と対向する。第２金型３２を第３金型３４に接合固定することにより、１次成形部分２ａで覆われていない素電池１および電装品が第３金型３４の成形空間３５に入り込む。この状態では、素電池１の上下面が第２金型３２と第３金型３４とで挟み保持され、しかも１次成形部分２ａが第２金型３２で固定保持されているので、素電池１や電装品が動くことはない。
【００４１】
上記の状態で第３金型３４の成形空間３５に溶融樹脂を充填することにより、図９および図１０に示すように、樹脂モールド２の２次成形部分２ｂが形成される。溶融樹脂が固化したのち、第２金型３２を第３金型３４から分離し、さらに素電池１を第２金型３２の成形空間３３からノックアウトすることにより、図１に示すように前後周面と左右周面が樹脂モールド２で覆われたパック電池が得られる。１次成形部分２ａと２次成形部分２ｂとの境界線を符号２２で示す。なお、樹脂モールド２の成形素材としては、ポリアミド樹脂、ポリウレタン樹脂、ポリカーボネイト樹脂、アクリルニトリルブタジエンスチレン樹脂などを適用できる。
【００４２】
（実施例２）実施例１では１次成形部分２ａと２次成形部分２ｂとが、素電池１の厚み方向中央を通る平面で分割されるようにしたが、その必要はなく、図１１に示すように、１次成形部分２ａと２次成形部分２ｂとが、素電池１の長手方向中途部を通る平面で分割されるように成形することができる。１次成形部分２ａと２次成形部分２ｂとの境界線を符号２２で示す。この実施例では、保護カバー１９を省略し、正負の出力端子１４・１５の外面に中子を配置して１次成形を行うようにした。従って、実施例１のパック電池とは異なり、正負の出力端子１４・１５を除く前面が１次成形部分２ａで覆われている。なお、中子は２次成形後に取り外され、その抜き跡が窓２０・２１と同様の開口として残る。他は実施例１と同じであるので、同じ部材に同じ符号を付してその説明を省略する。以下の実施例においても同じ扱いとする。
【００４３】
（実施例３）実施例１および実施例２においては、半被覆型のパック電池について説明したが、必要があれば全被覆型のパック電池を構成することができる。具体的には、図１２および図１３に示すように第２金型３２の成形空間３３を拡大して、素電池１と成形空間３３との間に溶融樹脂の入り込みを許す隙間Ｅ１を確保する。同様に第３金型３４の成形空間３５を拡大して、素電池１と成形空間３５との間に溶融樹脂の入り込みを許す隙間Ｅ２を確保する。１次成形時のブランクパックＰは、第１金型３０によってのみ固定支持されているが、ブランクパックＰと装填空間３１の嵌合をややきつめにすることで、溶融樹脂によってブランクパックＰが遊動するのを防止できる。得られた全被覆型のパック電池を図１３に示している。
【００４４】
上記の実施例以外に、半被覆型のパック電池において、素電池１の前後周面と、左右周面と、上下周面のいずれか一方を樹脂モールド２で覆うことができる。実施例においてはリード線９・１０を帯状の金属シートで形成したがその必要はなく、線状のリード線を適用できる。保護部品は実施例で説明した機能である必要はなく、パック電池の用途の違いに応じて必要な、電気部品や電子部品で構成することができる。
【図面の簡単な説明】
【図１】半被覆型の電池パックの斜視図である。
【図２】素電池とその電装品の分解斜視図である。
【図３】電装品を素電池に組み付けたブランクパックの斜視図である。
【図４】樹脂モールドの製造過程を示す説明図である。
【図５】ブランクパックを第１金型に装填した状態の底面図である。
【図６】１次成形時の図５におけるＡ−Ａ線断面図である。
【図７】１次成形時の図５におけるＢ−Ｂ線断面図である。
【図８】１次成形によって得られる成形ブランクの斜視図である。
【図９】２次成形時の図５におけるＡ−Ａ線断面図である。
【図１０】２次成形時の図５におけるＢ−Ｂ線断面図である。
【図１１】電池パックの別の実施例を示す斜視図である。
【図１２】全被覆型の電池パックの製造過程を示す説明図である。
【図１３】全被覆型の電池パックの斜視図である。
【符号の説明】
１素電池
２樹脂モールド
２ａ一次成形部分
２ｂ二次成形部分[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a battery pack in which a unit cell and electrical components attached to the unit cell are integrated by a resin mold, and a method for manufacturing the same.
[0002]
[Prior art]
It is known that a unit cell and an electrical component attached to the unit cell are integrated by a resin mold. This type of battery pack includes an all-enclosed battery pack (see Patent Document 1) in which a unit cell and all of its electrical components are embedded in a resin mold and only an output terminal portion is exposed, and a modularized protection pack. There is a partially covered type battery pack that covers only electrical components such as circuits, output terminals, or lead wires with a resin mold (see Patent Document 2). In the latter battery pack, the output terminal is covered with a resin mold, so that the output lead wire is led out from the protection circuit, and a connector is provided at the leading end.
[0003]
[Patent Document 1]
JP-A-2002-134077 (paragraph numbers 0021 to 22, FIG. 3)
[Patent Document 2]
JP 2000-315483 A (Paragraph number 0034, FIG. 3)
[0004]
[Problems to be solved by the invention]
According to the above-described battery pack, the entire unit cell and its electrical components are covered with a resin mold, or the electrical components such as a modularized protection circuit and output terminals are integrated with the unit cell with a resin mold. In addition, the labor required for assembling the electrical components can be saved, and the productivity can be improved. Further, since at least important components such as the protection circuit and the output terminal are covered with the resin mold, the insulation can be improved, and the disassembly of the battery pack can be made difficult to improve the safety. There is also an advantage that reliability can be improved by exhibiting a high degree of dustproofing and dripproofing. However, there is a problem whether it is a full coating type or a partial coating type.
[0005]
There is a problem in the molding technique in the full-pack type battery pack. In order to cover the entire outer surface of the blank pack, in which the electrical components are temporarily assembled with the unit cells, with the resin mold, it is necessary to support and position the entire peripheral surface of the blank pack away from the inner wall of the molding die. is there. In many cases, the blank pack is fixedly supported by a plurality of positioning pins provided on the inner surface of the molding die to prevent the blank pack from being moved by the molten resin injected into the die.
[0006]
For example, when positioning a thin rectangular box-shaped unit cell which is often found in a thin battery pack, it is necessary to fix and support at least five peripheral surfaces, that is, front and rear surfaces, left and right side surfaces, and a lower surface. However, if a number of positioning pins are provided in the molding space in this way, it is inevitable that holes formed by removing the positioning pins are formed on the peripheral surface of the obtained battery pack by the number of positioning pins. . If the lead wire faces the above-mentioned hole, the insulation of the battery pack is likely to be impaired. A battery pack having a number of holes has a problem in appearance due to the fact that this type of battery is often applied to small-sized electric devices such as mobile phones that are easily noticeable.
[0007]
On the other hand, in the partially covered type battery pack, only the necessary parts are covered with the resin mold, so that the battery pack can be formed without any problem in terms of molding technology. No holes for positioning pins are formed on the surface of the mold portion. However, the partially covered type battery pack has a problem in that since the resin mold portion is locally provided on a part of the peripheral surface of the unit cell, the symmetrical appearance of the battery pack is lost. For example, when a battery pack is applied to a small electric device such as a mobile phone, it is necessary to secure a battery accommodation space equal to the thickness and width dimensions of the resin mold portion, and further miniaturization and thinning are pursued. There is a disadvantage in a small electric device that a dead space is generated in the device. It is necessary to arrange the positive electrode terminal and the negative electrode terminal in the resin mold part, and there is also a problem that the structure of the unit cell is specialized. There is also a disadvantage that the insulation property is inferior to that of the all-covered type battery pack and the battery is easily decomposed.
[0008]
In order to maintain front-rear and left-right symmetry, four peripheral surfaces of the unit cell, for example, front-rear and left-right, are covered with a resin mold to form a semi-covered pack battery having no problem in the symmetry of the external shape. It is not impossible, but in that case, it is necessary to position the four peripheral surfaces of the unit cell with the positioning pins, which causes the problem of the positioning pins as in the case of the above-described fully-packed battery pack. The problem remains in the appearance of the battery pack.
[0009]
An object of the present invention is to improve the external appearance of a mold part and maintain the symmetry of the external shape, so that there is no waste in the battery accommodating space, and a small electric device which is required to be small and thin is required. It is to provide a suitable battery pack. An object of the present invention is to provide a fully-covered battery pack in which a unit cell and its electrical components are integrated by a resin mold, or a semi-covered battery pack in which at least four surroundings of the unit cell are covered with a resin mold. It is another object of the present invention to provide a method of manufacturing a battery pack that can be formed without deteriorating the appearance of each battery.
[0010]
[Means for Solving the Problems]
In the battery pack of the present invention, a thin rectangular box-shaped unit cell 1 and electrical components of the unit cell 1 arranged on the peripheral surface of the unit cell 1 are fixed by a resin mold 2 covering these outer surfaces. At least two pairs of opposing sides of the unit cell 1 are covered with the resin mold 2. The resin mold 2 includes a primary molded part 2a and a secondary molded part 2b (claim 1).
[0011]
The primary molded part 2a and the secondary molded part 2b are divided by a plane passing through the middle part in the thickness direction of the unit cell 1 (claim 2).
[0012]
The primary molded part 2a and the secondary molded part 2b are divided by a plane passing through a middle part in the longitudinal direction of the unit cell 1 (claim 3).
[0013]
Two pairs of opposing peripheral side surfaces of the unit cell 1 including the arrangement surface of the electrical components are covered with the resin mold 2 to constitute a semi-coated type battery pack.
[0014]
The entire outer surface of the unit cell 1 and the electrical components of the unit cell 1 is covered with a resin mold 2 to form a fully-covered type pack battery (claim 5).
[0015]
The electrical components include a first protective component 7 disposed on one of the front and rear peripheral surfaces of the unit cell 1, a second protective component 8 disposed on the other of the front and rear peripheral surfaces of the unit cell 1, and a left and right peripheral unit of the unit cell 1. It includes a lead wire 10 arranged on one of the surfaces to connect the first protection component 7 and the second protection component 8, and positive and negative output terminals 14 and 15 provided on the outer surface of the first protection component 7. (Claim 6).
[0016]
Output terminals 14 and 15 are protruded from the outer surface of the first protection component 7. On the outer surfaces of the first protection component 7 and the output terminals 14 and 15, a protection cover 19 for preventing the inflow of the molten resin is arranged. The protective cover 19 is fixed with the resin mold 2 (claim 7).
[0017]
In the method for manufacturing a battery pack of the present invention, as shown in FIG. 4, an assembling step of assembling electrical components attached to the battery cell 1 on the peripheral surface of the battery cell 1 in the shape of a thin rectangular box to form a blank pack P After the blank pack P is loaded into the loading space 31 of the first mold 30 and the blank pack P is positioned and fixed by the first mold 30, the second mold 32 is joined and fixed to the first mold 30. A preparatory step and a step of forming a primary molded part 2a of the resin mold 2 by filling the peripheral surface of the unit cell 1 exposed in the molding space 33 of the second mold 32 and the electrical components of the unit cell 1 with molten resin. After the second molding 32 is separated from the first molding 30 in a state including the primary molding step, the unit cell 1, the electric components of the unit cell 1, and the primary molding portion 2 a, the second molding A second-stage preparation step of joining and fixing the second mold 32 to the third mold 34 and forming the third mold 34 And a secondary molding step of filling the peripheral surface of the unit cell 1 exposed in the space 35 and the peripheral surface of the electrical components of the unit cell 1 with a molten resin to form the secondary molded portion 2b of the resin mold 2. The resin mold 2 is formed so as to cover at least two pairs of opposing sides (claim 8).
[0018]
The boundary surface between the primary molded part 2a and the secondary molded part 2b is set on a plane passing through a halfway part in the thickness direction of the unit cell 1 (claim 9).
[0019]
The boundary surface between the primary molded portion 2a and the secondary molded portion 2b is set on a plane passing through a halfway portion of the unit cell 1 in the longitudinal direction (claim 10).
[0020]
Effects of the Invention
In the battery pack of the present invention, when the electric component is integrated with the unit cell 1 by covering at least four peripheral surfaces of the unit cell 1 with the resin mold 2, the resin mold 2 is formed into the primary molding portion 2 a and the secondary molding unit 2. When the primary molded part 2a is molded, the non-molded part of the unit cell 1 or the electrical component assembled to the unit cell 1 can be fitted and fixed to the first mold 30 when forming the primary molded part 2a. . In other words, the primary molded part 2a can be molded with one of the molding dies holding the unit cell 1 and the electrical components fixed. As described above, when the unit cell 1 and the electrical component are directly fixed and held by the molding die, there is no need to provide pins or protrusions for positioning the unit cell 1 and the electrical component inside the mold. In addition, it is possible to eliminate the formation of pins and protrusions on the protrusions, to form the resin mold 2 having an excellent appearance, and to maintain the symmetry of the appearance. Therefore, a battery pack suitable for a small-sized electric device requiring a small size and a thin shape without wasting the battery accommodation space can be obtained. When the secondary molded part 2b is molded, the secondary molded part 2b can be formed without any problem since the primary molded part 2a is fixedly held in the mold.
[0021]
According to the battery pack in which the primary molded part 2a and the secondary molded part 2b are divided by a plane passing through the middle part in the thickness direction of the unit cell 1, the molding space of each of the molds 30, 32, and 34 for molding the resin mold 2. Since the depths 31, 33, and 35 can be reduced, the mold release can be easily performed. There is also an advantage that the operation for loading the blank pack P, in which the electrical components are assembled in the unit cell 1, into the mold can be easily performed (claim 2).
[0022]
According to the battery pack in which the primary molded portion 2a and the secondary molded portion 2b are divided by a plane passing through the middle part in the longitudinal direction of the unit cell 1, the boundary line 22 between the molded portions 2a and 2b can be minimized. Thus, a battery pack with a good appearance can be obtained by minimizing the appearance of the boundary line 22. Since the contact area between the primary molded part 2a and the secondary molded part 2b and the unit cell 1 can be substantially equalized, the characteristics of the resin mold 2 around the unit cell 1, such as insulation, dust resistance, drip resistance, etc. Can be made uniform (claim 3).
[0023]
According to the semi-covered battery pack in which two opposing peripheral side surfaces of the unit battery 1 including the arrangement surface of the electrical components are covered with the resin mold 2, the battery pack can be configured without deteriorating the symmetry of the external shape. Therefore, for example, the battery housing space when the battery pack is applied to a small electric device such as a mobile phone can be reduced as compared with a partially covered battery pack in which a thick resin mold is formed partially. Since the four peripheral surfaces of the unit cell 1 are covered with the resin mold 2, it is not necessary to arrange the positive electrode terminal 6 and the negative electrode terminal in the resin mold part, which are indispensable for a partially covered type battery pack. This is advantageous in that the unit cell 1 may be manufactured in the above manner (claim 4).
[0024]
According to the full-cover type battery pack in which the entire outer surface of the unit cell 1 and the electrical components of the unit cell 1 are covered with the resin mold 2, the entire outer surface of the unit cell 1 is covered with the resin mold 2 as well as the electrical components. In addition to being able to improve the insulating properties, it is also possible to make the disassembly of the battery pack difficult, thereby improving the safety. The properties such as insulation, dust resistance and drip resistance can be improved (claim 5).
[0025]
Including a first protection component 7 and a second protection component 8 disposed on the front and rear peripheral surfaces of the unit cell 1, a lead wire 10 connecting the two protection components 7.8, and positive and negative output terminals 14 and 15. When the electrical components are configured and these electrical components are integrated with the unit cell 1 by the resin mold 2, the protection function is added to the battery pack itself, and the safety in the event of an abnormality can be improved, and the reliability of the battery pack is correspondingly increased. Can be improved (claim 6).
[0026]
According to the battery pack in which the protective cover 19 for preventing the inflow of the molten resin is arranged on the outer surface of the first protective component 7, the positive and negative output terminals 14 and 15 provided on the outer surface of the first protective component 7 are made of the molten resin at the time of molding. In addition to being reliably prevented from being covered, the protective cover 19 reinforces the unit cell 1 and improves the structural strength of the battery pack. The protective cover 19 also helps to prevent other objects from simultaneously contacting the positive and negative output terminals 14 and 15 to cause a short circuit. This is because the positive and negative output terminals 14 and 15 are located inside the opening surfaces of the windows 20 and 21 provided in the protective cover 19 (claim 7).
[0027]
In the manufacturing method of the battery pack of the present invention, after the electrical components are assembled to the unit cell 1 to form the blank pack P, the blank pack P is loaded into the loading space 31 of the first mold 30 and positioned and fixed. The second mold 32 joined to the first mold 30 was filled with the molten resin to form the primary molded portion 2a of the resin mold 2. Subsequently, the second mold 32 is replaced with a third mold 34, and the molding space 35 of the third mold 34 is filled with a molten resin to form the secondary molding portion 2b of the resin mold 2, A battery pack in which at least four peripheral portions are covered with the resin mold 2 is formed. Therefore, in the method for manufacturing a battery pack of the present invention, it is not necessary to provide positioning pins, which are indispensable for forming a resin mold by a conventional injection molding method, inside each of the molds 30, 32, and 34. It is possible to mass-produce a semi-covered type or full-covered type pack battery capable of improving the above appearance (claim 8).
[0028]
When the resin mold 2 is molded by setting the boundary surface between the primary molded part 2a and the secondary molded part 2b on a plane passing through the middle part in the thickness direction of the unit cell 1, each mold 30 for molding the resin mold 2 is formed.・ Since the molding spaces 31, 33, 35 of 32, 34 can be made shallower, the mold can be easily released, and the operation for loading the blank pack P into the mold can be performed quickly and simply. (Claim 9).
[0029]
When the resin mold 2 is molded by setting the boundary surface between the primary molded portion 2a and the secondary molded portion 2b on a plane passing through the middle part of the unit cell 1 in the longitudinal direction, the boundary line 22 between the molded portions 2a and 2b is formed. Can be minimized, so that a battery pack with a good appearance can be obtained. Since the contact area between the primary molded portion 2a and the secondary molded portion 2b and the unit cell 1 can be substantially equalized, the characteristics of the resin mold 2 around the unit cell 1, for example, insulation, dust resistance, and drip resistance And the like can be made uniform (claim 10).
[0030]
【Example】
Embodiment 1 FIGS. 1 to 10 show Embodiment 1 of a battery pack according to the present invention. In FIG. 2, the battery pack comprises a thin rectangular box-shaped unit cell 1, electrical components arranged on the peripheral surface of the unit cell 1, and a resin mold 2 covering the outer peripheral surface of the unit cell 1 except for the upper and lower surfaces. It is configured as a coated battery pack.
[0031]
The unit cell 1 is composed of a chargeable / dischargeable secondary battery in which an electrode body and an electrolytic solution are sealed inside an outer can 4, for example, a lithium ion battery, and a positive electrode is provided at the center of a sealing plate 5 that covers the front surface of the outer can 4. The terminal 6 is provided. The outer can 4 is formed by deep drawing a nickel plate or an aluminum plate, and also serves as an output terminal on the negative electrode side. The electrode body is formed by spirally winding a positive electrode sheet using LiCoO ₂ as an active material and a negative electrode sheet using graphite as an active material with a separator interposed therebetween, and crushing the whole flat to deform.
[0032]
In FIG. 2, the electrical components include a protection circuit module (first protection component) 7 disposed on the front side of the unit cell 1, a polyswitch (second protection component) 8 disposed on the rear side of the unit cell 1, These are composed of both the long and short conductive sheets (lead wires) 9 and 10 for connecting the positive terminal 6 and the protection circuit module 7 respectively.
[0033]
The protection circuit module 7 is formed of a square rod-shaped plastic molded product in which a control circuit for controlling the charging / discharging current of the unit cell 1 is embedded, and strip-shaped connection leads 12 and 13 are provided at both ends. By providing the above control circuit, overdischarge and overcharge of the unit cell 1 can be prevented. On the front surface of the protection circuit module 7, an output terminal 14 on the positive electrode side and an output terminal 15 on the negative electrode side are protruded. The polyswitch 8 is provided to cut off the current of the unit cell 1 when the temperature of the unit cell 1 exceeds a set value, and a connection lead 16 is fixed to one end thereof. The upper and lower thickness dimensions of the protection circuit module 7 and the polyswitch 8 are set slightly smaller than the thickness dimension of the unit cell 1. Each of the conductive sheets 9 and 10 and each of the connection leads 12, 13 and 16 are formed by cutting a thin sheet of a conductive metal such as copper or aluminum into a strip shape, and the vertical dimension thereof is set to the protection circuit module 7. Is set to be smaller than the upper and lower thickness dimensions.
[0034]
A blank pack P shown in FIG. 3 is obtained by assembling the above-mentioned electrical components to the unit cell 1 and further mounting and fixing a protective cover 19 on the front surface of the protective circuit module 7. Specifically, the short conductive sheet 9 and the long conductive sheet 10 are spot-welded to the connection leads 12 and 13 at the left and right ends of the protection circuit module 7 respectively, and the connection lead 16 of the polyswitch 8 is further connected to the rear end of the long conductive sheet 10. Spot welding to connect electrical components. Next, after the conductive sheet 9 is attached to the positive electrode terminal 6 and the sealing plate 5 via an insulating double-sided tape, the conductive sheet 9 is spot-welded to the positive electrode terminal 6. Similarly, the conductive sheet 10 is attached to one side surface of the unit cell 1 via an insulating double-sided tape, and the polyswitch 8 is attached to the rear surface of the unit cell 1 via an insulating double-sided tape. The surface is spot-welded to the outer can 4.
[0035]
As shown in FIG. 2, the protective cover 19 is formed of a strip-shaped plastic molded product, and windows 20 and 21 corresponding to the positive and negative output terminals 14 and 15 of the protective circuit module 7 are opened on the plate surface. The blank pack P can be completed by attaching the protection cover 19 to the front surface of the protection circuit module 7 with the positive and negative output terminals 14 and 15 fitted in the windows 20 and 21. The front and rear surfaces and the left and right surfaces of the unit cell 1 and the electrical component can be covered with the resin mold 2 by insert molding the blank pack P by an injection molding machine in a manner described later.
[0036]
The resin mold 2 is formed by the following procedure.
As shown in FIG. 4A, an assembling step of assembling electrical components on the peripheral surface of the unit cell 1 to form a blank pack P;
As shown in FIG. 4B, the blank pack P was loaded into the loading space (molding space) 31 of the first mold 30, and the blank pack P was positioned and fixed by the first mold (fixed mold) 30. After that, a preparatory step for joining and fixing the second mold (movable mold) 32 to the first mold 30;
As shown in FIG. 4C, the unit cell 1 exposed in the molding space 33 of the second mold 32 and the peripheral surface of the electrical component are filled with a molten resin, and the primary molding portion 2a of the resin mold 2 is formed. A primary molding step for forming;
As shown in FIG. 4D, the second mold 32 is separated from the first mold 30 in a state including the unit cell 1, the electric component, and the primary molded portion 2a, and then the second mold 32 is removed. A post-stage preparation step of joining and fixing to a third mold (fixed mold) 34;
As shown in FIG. 4E, the unit cell 1 exposed in the molding space 35 of the third mold 34 and the peripheral surface of the electrical component are filled with a molten resin, and the secondary molded portion 2b of the resin mold 2 is removed. Through the secondary molding process to form,
That is, the resin mold 2 that covers the front and rear sides and the left and right sides of the unit cell 1 is formed by the two-color molding method.
[0037]
In the preparatory step, when the blank pack P is loaded in the loading space 31 of the first mold 30, as shown in FIG. Are received by front and rear walls of the loading space 31, and the conductive sheet 10 and the side surface of the unit cell 1 are received by left and right walls of the loading space 31. That is, the blank pack P is positioned by the first mold 30 without using positioning pins, and is fixed and held non-movably. In this loaded state, the unit cell 1 and the electrical component have entered only half the vertical dimension into the loading space 31. Therefore, when the second mold 32 is fixedly joined to the first mold 30, as shown in FIGS. 6 and 7, only half of the unit cell 1 and the electrical components enter the molding space 33, and The upper and lower surfaces of the battery 1 are held between the first and second molds 30 and 32.
[0038]
As described above, when the blank pack P is fixed and held by the first mold 30 and the upper and lower surfaces of the unit cell 1 are sandwiched and held by the first and second molds 30 and 32, the second pack is formed in the first molding step. Even if the molten resin is injected into the molding space 33 of the mold 32, the blank pack P is not moved by the pressure or flow action of the molten resin, and the primary molded portion 2a having a constant shape can always be formed. A protection cover 19 is provided on the outer surface of the protection circuit module 7 in order to prevent the molten resin from flowing into the outer surfaces of the positive and negative output terminals 14 and 15 during the primary molding and the secondary molding. Some gaps are formed between the front and rear surfaces of the unit cell 1 and the front surface of the loading space 31 of the first mold 30, but the molten resin enters these gaps during the primary molding. The injection of the molten resin may be performed from the first mold 30 side or from the second mold 32 side.
[0039]
As shown in FIG. 8, the molded blank obtained in the primary molding step has a primary molded portion 2 a slightly wider than the unit cell 1, and has an outer surface of the protection circuit module 7 and an outer surface of the polyswitch 8. Are covered with the molded resin. The primary molded part 2a is shown by stippling.
[0040]
In the latter preparation step, the second mold 32 is separated from the first mold 30 and joined to the third mold 34. At this time, the second mold 32 rotates around an axis (not shown). Another second mold facing the third mold 34, facing the third mold 34, and from which the battery pack is released faces the first mold 30. By bonding and fixing the second mold 32 to the third mold 34, the unit cells 1 and the electrical components not covered by the primary molded part 2 a enter the molding space 35 of the third mold 34. In this state, the upper and lower surfaces of the unit cell 1 are sandwiched and held between the second mold 32 and the third mold 34, and the primary molded part 2 a is fixed and held by the second mold 32. 1 and electrical components do not move.
[0041]
By filling the molding space 35 of the third mold 34 with the molten resin in the above state, the secondary molding portion 2b of the resin mold 2 is formed as shown in FIGS. After the molten resin is solidified, the second mold 32 is separated from the third mold 34, and the unit cell 1 is knocked out of the molding space 33 of the second mold 32, so that the front and rear circumferences as shown in FIG. A battery pack whose surface and left and right peripheral surfaces are covered with the resin mold 2 is obtained. Reference numeral 22 indicates a boundary between the primary molded portion 2a and the secondary molded portion 2b. In addition, as a molding material of the resin mold 2, a polyamide resin, a polyurethane resin, a polycarbonate resin, an acrylonitrile butadiene styrene resin, or the like can be applied.
[0042]
(Example 2) In Example 1, the primary molded part 2a and the secondary molded part 2b are divided by a plane passing through the center in the thickness direction of the unit cell 1, but this is not necessary. As shown, the primary molded part 2a and the secondary molded part 2b can be molded so as to be divided by a plane passing through the middle part of the unit cell 1 in the longitudinal direction. Reference numeral 22 indicates a boundary between the primary molded portion 2a and the secondary molded portion 2b. In this embodiment, the primary cover is formed by omitting the protective cover 19 and disposing a core on the outer surface of the positive and negative output terminals 14 and 15. Therefore, unlike the battery pack of the first embodiment, the front surface excluding the positive and negative output terminals 14 and 15 is covered with the primary molded portion 2a. Note that the core is removed after the secondary molding, and the trace of the core remains as an opening similar to the windows 20 and 21. Other components are the same as those in the first embodiment, and thus the same members are denoted by the same reference numerals and description thereof will be omitted. The same applies to the following embodiments.
[0043]
Third Embodiment In the first and second embodiments, a semi-coated battery pack has been described. However, if necessary, an all-coated battery pack can be configured. Specifically, as shown in FIGS. 12 and 13, the molding space 33 of the second mold 32 is enlarged to secure a gap E1 between the unit cell 1 and the molding space 33 that allows the molten resin to enter. . Similarly, the molding space 35 of the third mold 34 is enlarged to secure a gap E2 between the unit cell 1 and the molding space 35 that allows the molten resin to enter. Although the blank pack P at the time of the primary molding is fixed and supported only by the first mold 30, the fitting of the blank pack P and the loading space 31 is made slightly tight, so that the blank pack P is Idleness can be prevented. FIG. 13 shows the obtained all-covered battery pack.
[0044]
In addition to the above embodiments, in a semi-coated battery pack, any one of the front and rear peripheral surfaces, the left and right peripheral surfaces, and the upper and lower peripheral surfaces of the unit cell 1 can be covered with the resin mold 2. In the embodiment, the lead wires 9 and 10 are formed of a band-shaped metal sheet, but this is not necessary, and a linear lead wire can be applied. The protection component does not need to have the function described in the embodiment, and can be configured by an electrical component or an electronic component required according to the difference in the use of the battery pack.
[Brief description of the drawings]
FIG. 1 is a perspective view of a semi-coated battery pack.
FIG. 2 is an exploded perspective view of a unit cell and its electrical components.
FIG. 3 is a perspective view of a blank pack in which electric components are assembled to a unit cell.
FIG. 4 is an explanatory diagram showing a manufacturing process of the resin mold.
FIG. 5 is a bottom view of a state where a blank pack is loaded in a first mold.
FIG. 6 is a sectional view taken along line AA in FIG. 5 at the time of primary molding.
FIG. 7 is a sectional view taken along line BB in FIG. 5 at the time of primary molding.
FIG. 8 is a perspective view of a molded blank obtained by primary molding.
FIG. 9 is a sectional view taken along line AA in FIG. 5 during secondary molding.
FIG. 10 is a sectional view taken along the line BB in FIG. 5 during secondary molding.
FIG. 11 is a perspective view showing another embodiment of the battery pack.
FIG. 12 is an explanatory diagram showing a manufacturing process of a fully-coated battery pack.
FIG. 13 is a perspective view of a fully covered battery pack.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Unit cell 2 Resin mold 2a Primary molded part 2b Secondary molded part

Claims

A battery pack in which a thin rectangular box-shaped unit cell and electric components of the unit cell arranged on the peripheral surface of the unit cell are fixed with a resin mold covering these outer surfaces,
At least two pairs of opposing sides of the unit cell are covered with the resin mold,
A battery pack according to claim 1, wherein said resin mold comprises a primary molded part and a secondary molded part.

2. The battery pack according to claim 1, wherein the primary molded portion and the secondary molded portion are divided by a plane passing through an intermediate portion in a thickness direction of the unit cell. 3.

2. The battery pack according to claim 1, wherein the primary molded portion and the secondary molded portion are divided by a plane passing through an intermediate portion in the longitudinal direction of the unit cell. 3.

4. The battery pack according to claim 1, wherein two pairs of opposing peripheral side surfaces of the unit cell including the arrangement surface of the electrical component are covered with the resin mold. 5.

The battery pack according to any one of claims 1 to 3, wherein the entire outer surfaces of the unit cell and electrical components of the unit cell are covered with the resin mold.

A first protection component disposed on one of the front and rear peripheral surfaces of the unit cell, a second protection component disposed on the other of the front and rear peripheral surfaces of the unit cell, and a left and right peripheral surface of the unit cell And a lead wire connected to the first protection component and the second protection component, and a positive / negative output terminal provided on an outer surface of the first protection component. The battery pack according to any one of the above.

The output terminal protrudes from an outer surface of the first protection component, and a protection cover for preventing inflow of molten resin is disposed on the outer surface of the first protection component and the output terminal. The battery pack according to any one of claims 1 to 6.

An assembling step of forming a blank pack by assembling electrical components attached to the unit cell on the peripheral surface of the unit cell in the shape of a thin rectangular box,
A preparatory step of loading the blank pack into a loading space of a first mold, positioning and fixing the blank pack with the first mold, and then bonding and fixing a second mold to the first mold;
A primary molding step of filling the peripheral surface of the unit cell exposed in the molding space of the second mold and an electrical component of the unit cell with molten resin to form a primary molded part of a resin mold;
After separating the second mold from the first mold in a state including the unit cell, the electrical components of the unit cell, and the primary molded portion, the second mold is changed to a third mold. A post-stage preparation step for joining and fixing,
A secondary molding step of filling the peripheral surface of the unit cell exposed in the molding space of the third mold and an electrical component of the unit cell with a molten resin to form a secondary molded portion of the resin mold. Through,
A method of manufacturing a battery pack, comprising: forming the resin mold to cover at least two pairs of opposing sides of the unit cell.

9. The method for manufacturing a battery pack according to claim 8, wherein a boundary surface between the primary molded part and the secondary molded part is set on a plane passing through an intermediate part in a thickness direction of the unit cell.

9. The method for manufacturing a battery pack according to claim 8, wherein a boundary surface between the primary molded portion and the secondary molded portion is set on a plane passing through a middle part in a longitudinal direction of the unit cell. 10.