【０００１】
【発明の属する技術分野】
本発明は、二次電池の接続構造に関し、特に、隣接するセル間の端子を接続させる二次電池の接続構造及び接続方法に関する。
【０００２】
【従来の技術】
一般に、リチウムイオン二次電池の定格電圧は３．７Ｖである。そこで、より大きな起電力を得るために複数のリチウムイオン二次電池を直列に接続し、リチウムイオン二次電池の組電池を構成することが行われる。この場合、隣接するセル（リチウムイオン二次電池）間の異極端子が銅材等の導電体からなる端子接続用部材により接続される。そして、従来、隣接するセル間の異極端子を接続させる場合、当該異極端子間に端子接続用部材を掛け渡し、各端子に螺設された雌ねじにボルトを螺合して各端子と端子接続用部材とを締結させて接続することが行われていた。しかしながら、上記従来の接続構造では、端子と端子接続用部材とを締結させるボルトの締付けトルクが規定されているが、充放電が繰り返し行われることや使用環境等によりボルトが弛緩することがある。このように、ボルトが弛緩した場合、端子と端子接続用部材との接触部の電気抵抗が増大し、出力を損失する虞がある。
【０００３】
また、端子及び端子接続用部材は導電性に優れるアルミ材や銅材により形成されるので、各セル（リチウムイオン二次電池）の内部温度の上昇等のストレスにより端子接続用部材と端子との接触部に電気的腐食が生じ易く、電気抵抗が増大される虞がある。そこで、ニッケル材の単材構造を有する溶接部と、ニッケル材とアルミ材又は銅材との複数材の積層構造を有する導電部とで構成され、溶接部がセルのニッケルで覆われた端子に溶接されて接合されて隣接するセル間の端子が接続される接続板（端子接続用部材）が特許文献１に記載されている。該特許文献１に記載の接続板によれば、溶接部の端子への溶接が容易になり、溶接の作業性及び信頼性が向上されると共に導電部が低電気抵抗で電流を流すことで出力損失が抑制される。しかしながら、この接続板は、サイズが小さいため取り扱いが難しく、溶接時に端子に対して位置決めさせるのが困難で作業性を低下させていた。さらに、上記接続板は、ニッケル材とアルミ材又は銅材との複数材の積層構造により形成されるので高価になり、製造コストを増大させる要因になっていた。
【０００４】
【特許文献１】
特開２０００−３６２９９号公報（段落番号００１１〜００１７、第６図）
【０００５】
【発明が解決しようとする課題】
そこで本発明は、上記事情に鑑みてなされたもので、端子及び端子接続用部材の腐食を防止すると共に隣接するセル間の端子を容易に且つ確実に接続することができる二次電池の接続構造及び接続方法を提供することを目的とする。
【０００６】
【課題を解決するための手段】
上記目的を達成するために、本発明のうち請求項１に記載の発明は、隣接するセル間の端子を端子接続用部材で接続させる二次電池の接続構造であって、端子と端子接続用部材とがはんだめっきされることを特徴とする。
【０００７】
請求項２に記載の発明は、請求項１に記載の発明において、端子接続用部材は両端にクリップ部が配設され、各クリップ部が各端子に接続されることを特徴とする。
【０００８】
請求項３に記載の発明は、請求項１又は２に記載の発明において、端子と端子接続用部材とが金属接合されることを特徴とする。
【０００９】
上記目的を達成するために、本発明のうち請求項４に記載の発明は、隣接するセル間の端子を端子接続用部材で接続させる二次電池の接続方法であって、端子と端子接続用部材とをはんだめっきしておいて、該端子接続用部材の両端の各クリップ部を相互に接続させる各端子に接続させ、次に各クリップ部と各端子とを金属接合させることを特徴とする。
【００１０】
従って、請求項１に記載の発明では、端子及び端子接続用部材がはんだめっきにより被覆されて端子及び端子接続用部材の母材となるアルミ材や銅材等が剥き出されていないため、端子及び端子接続用部材の腐食が防止される。
【００１１】
請求項２に記載の発明では、端子と端子接続用部材との接続（端子に対する端子接続用部材の位置決め、取付け）が容易になる。
【００１２】
請求項３に記載の発明では、ボルトやナットによる締結が廃止され、端子と端子接続用部材とを容易に、且つ確実に接続することができる。
【００１３】
請求項４に記載の発明では、端子と端子接続用部材とを予めはんだめっきしておいて、該端子接続用部材の両端の各クリップ部を相互に接続させる各端子に接続させて、各クリップ部と各端子とを金属接合させることにより、隣接するセル間の端子が接続される。
【００１４】
【発明の実施の形態】
本発明の一実施の形態を図１〜図５に基づいて説明する。図１に示すように、本二次電池１の接続構造は、隣接して配置されたセル２（本実施の形態ではリチウムイオン二次電池の単電池）間の端子３，４を導電体からなる端子接続用部材５により直列に接続させる二次電池１の接続構造であって、各セル２の各端子３，４と端子接続用部材５との双方がはんだめっきされ、端子接続用部材５の両端のクリップ部６を相互に接続させる各端子３，４に接続させて当該各端子３，４を接続させ、接続された各端子３，４と各クリップ部６とを超音波接合（金属接合）させることにより、隣接して配置されたセル２間の端子３，４が接続される構造になっている。図２に示すように、セル２は、ラミネート加工された金属製ケーシング７の一面に板状の正極端子３と負極端子４とが配設されている。また、図３に示すように、上記ケーシング７内には、正極板８、負極板９、セパレータ１０及び電解液１１が収容されている。
【００１５】
上記正極板８は、アルミ基板に正極活物質が薄層状に塗布されて形成され、一体で形成された正極端子３にははんだめっきが施されている。上記負極板９は、銅基板に炭素材料と結着材との混合物を有機溶剤でペースト状にしたものを薄層状に塗布して形成され、一体で形成された負極端子４にははんだめっきが施されている。上記電解液１１は、混合溶媒を主体とする有機電解液であって、例えば、高誘電率溶媒として、エチレンカーボネート（ＥＣ）、プロピレンカーボネート（ＰＣ）、γ−ブチロラクトン（γ−ＢＬ）、ジメチルスルホキシド（ＤＭＳＯ）、また低粘度溶媒として、ジメチルカーボネード（ＤＭＣ）、ジメトキシエタン（ＤＭＥ）等が用いられている。さらに、電解液１１にイオン伝導性を付与する支持電解質には、六弗化燐酸リチウム（ＬｉＰＦ６）、過塩素酸リチウム（ＬｉＣｌＯ４）、四弗化ホウ酸リチウム（ＬｉＢＦ４）、六弗化ヒ酸リチウム（ＬｉＡｓＦ６）等のリチウム塩が用いられている。
【００１６】
また、上記セパレータ１０は、電流遮断機能を有するポリエチレンやポリプロピレン等の微多孔膜により形成され、電解液１１を保持すると共にをケーシング７内を正極と負極とに分離させる構造になっている。図４に示すように、上記端子接続用部材５は、一対のクリップ部６が連接部５ａで連接されて形成されている。各クリップ部６は、所定間隔を有して対向する一対の挟持片６ａの一側が連接片６ｂで連接されて断面が略コ字状に形成され、対向する一対の挟持片６ａのうち一方の挟持片６ａが連接片６ｂに接続されている。なお、上記連接片６ｂには、端子３，４との接続時に当該端子３，４を挿通させて貫通させるための端子挿通用孔６ｃが形成されている。また、端子接続用部材５は、銅材からなる母材のクリップ部６を含む全面にはんだめっきが施されている。
【００１７】
そして、図１に示すように、本二次電池１の接続構造は、端子接続用部材５の両端の各クリップ部６の各端子挿通用孔６ｃに隣接するセル２間の相互に接続させる各端子３，４を挿通させて貫通させて各クリップ部６の挟持片６ａの一対で各端子３，４を挟持させることにより、各端子３，４を端子接続用部材５で接続させる構造になっている。さらに、本二次電池１の接続構造は、接続された各端子３，４と端子接続用部材５の両端の各クリップ部６とを超音波接合（金属接合）させて固着させる構造になっている。
【００１８】
次に、本実施の形態の作用を説明する。なお、ここでは、上記端子接続用部材５を用いて複数個（本実施の形態では４個）のセル２（リチウムイオン二次電池の単電池）を直列に接続させる場合を説明する。まず、図５に示すように、セル配列方向（図５における紙面視左右方向）に正極端子３と負極端子４とが交互に配置される向きに各セル２を配置する。そして、セル配列方向両側に配置された各セル２のうち、負極端子４が外部負極端子に接続される図５における紙面視で右端に配置されたセル２の正極端子３に端子接続用部材５の一方のクリップ部６を接続させると共に当該セル２に隣接する右から２番目に配置されたセル２の負極端子４に端子接続用部材５の他方のクリップ部６を接続させて、右端に配置されたセル２の正極端子３と右から２番目に配置されたセル２の負極端子４とを端子接続用部材５により接続させる。
【００１９】
次に、図５における紙面視で右から２番目に配置されたセル２の正極端子３と右から３番目に配置されたセル２の負極端子４とを、さらに右から３番目に配置されたセル２の正極端子３と正極端子３が外部正極端子に接続される図５における紙面視で左端に配置されたセル２の負極端子４とを、端子接続用部材５により順次接続させる。そして、各端子接続用部材５の両端の各クリップ部６と各端子３，４とを超音波接合（金属接合）により接合させる。これにより、図１に示すように、４個のリチウムイオン二次電池の単電池（セル２）が直列に接続された組電池（二次電池１）が構成される。
【００２０】
この実施の形態では以下の効果を奏する。
本二次電池１の接続構造は、各セル２の端子３，４と端子接続用部材５とにはんだめっきが施されたので、アルミ材（正極端子３）や銅材（負極端子４及び端子接続用部材５）が外気に晒されて腐食することがなく、低電気抵抗が長期に亘り維持されて電池としての安定した性能を確保することが可能になる。
本二次電池１の接続構造は、隣接するセル２間の端子３，４に端子接続用部材５の両端のクリップ部６を接続させて当該端子３，４を接続させたので、ボルト等で端子３，４と端子接続用部材５とを締結させる従来の接続構造と比較して、端子３，４と端子接続用部材５との接続が容易になり、端子接続の作業効率を向上させることが可能になる。また、端子接続用部材５は、各クリップ部６の端子挿通用孔６ｃに各端子３，４が挿通されて貫通されるので、各クリップ部６と各端子３，４とを確実に接続することができる。さらに、本二次電池１の接続構造は、各端子３，４が各クリップ６の対向する一対の挟持片６ａにより挟持されるので、各端子３，４と端子接続用部材５との接触面積が大きく、放熱性を高めることができる。従って、各セル２のストレスが緩和され各セル２の劣化を防止することができる。
本二次電池１の接続構造は、接続された各端子３，４と端子接続用部材５の各クリップ部６とが超音波接合（金属接合）されて固着される。従って、本二次電池１の接続構造は、ボルト等で端子３，４と端子接続用部材５とを締結させる従来の接続構造と比較して、端子３，４と端子接続用部材５との接続が容易であると共にボルト等が弛緩するようなことがないので、各端子３，４と端子接続用部材５の各クリップ部６とを確実に接続することが可能になる。また、上記従来の接続構造と比較して部品点数が減少し、製造コストを削減することができる。さらに、接続される端子３，４と端子接続用部材５との双方に予めはんだめっきが施されるので、はんだめっきによる接合の際のフラックスが必要なく、フラックスを用いた場合に必需となるスラグや残滓の除去作業を廃止することができる。
【００２１】
なお、実施の形態は上記に限定されるものではなく、例えば次のように構成してもよい。
本実施の形態では、複数個のリチウムイオン二次電池の単電池（セル２）を接続させる二次電池１の接続構造について説明したが、接続される単電池（セル２）はリチウムイオン二次電池に限らず、端子接続用部材５を用いた本接続構造を、例えば、電池とコンデンサとの中間の容量を有する電気二重層キャパシタを接続する場合に採用してもよい。
各セル２の各端子３，４及び端子接続用部材５に施されるはんだめっきは、Ｓｎめっき或いはＳｎ合金めっきを必要に応じて選定すればよい。
接続された各端子３，４と端子接続用部材５の各クリップ部６との接合は、金属接合で確実に接合されるものであればよく、例えば、抵抗溶接、圧接、はんだ接合、塑性締結等であってもよい。
【００２２】
【発明の効果】
以上詳述したように、本発明によれば、端子及び端子接続用部材の腐食を防止すると共に隣接するセル間の端子を容易に且つ確実に接続することができる二次電池の接続構造及び接続方法を提供することができる。
【図面の簡単な説明】
【図１】本二次電池の接続構造の斜視図である。
【図２】セル（リチウムイオン二次電池）単体の斜視図である。
【図３】セル（リチウムイオン二次電池）の概略構造を示す図である。
【図４】端子接続用部材の斜視図である。
【図５】セルを直列に接続させる際のセルの配列を示す平面図である。
【符号の説明】
１ 二次電池
２ セル（リチウムイオン二次電池）
３ 正極端子
４ 負極端子
５ 端子接続用部材
６ クリップ部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a connection structure of a secondary battery, and more particularly, to a connection structure and a connection method of a secondary battery for connecting terminals between adjacent cells.
[0002]
[Prior art]
Generally, the rated voltage of a lithium ion secondary battery is 3.7V. Therefore, in order to obtain a larger electromotive force, a plurality of lithium ion secondary batteries are connected in series to form an assembled battery of the lithium ion secondary batteries. In this case, the different terminal between adjacent cells (lithium ion secondary batteries) is connected by a terminal connecting member made of a conductor such as a copper material. Conventionally, when connecting different-polarity terminals between adjacent cells, a terminal connection member is bridged between the different-polarity terminals, and a bolt is screwed into a female screw threaded at each terminal to connect each terminal to the terminal. Connection has been performed by fastening with a connection member. However, in the above-described conventional connection structure, the tightening torque of the bolt for fastening the terminal and the terminal connection member is specified. However, the bolt may be loosened due to repeated charging and discharging and the use environment. Thus, when the bolt is loosened, the electric resistance of the contact portion between the terminal and the terminal connecting member increases, and there is a possibility that the output is lost.
[0003]
In addition, since the terminal and the terminal connecting member are formed of an aluminum or copper material having excellent conductivity, the terminal connecting member and the terminal may be connected to each other by a stress such as an increase in the internal temperature of each cell (lithium ion secondary battery). Electrical corrosion is likely to occur in the contact portion, and the electrical resistance may be increased. Therefore, a terminal composed of a welded portion having a single material structure of a nickel material and a conductive portion having a laminated structure of a plurality of materials of a nickel material and an aluminum material or a copper material, wherein the welded portion is covered with nickel of the cell. Patent Literature 1 discloses a connection plate (terminal connection member) to which terminals between adjacent cells are welded and joined to be connected. According to the connection plate described in Patent Literature 1, welding of a welded portion to a terminal is facilitated, workability and reliability of welding are improved, and output is achieved by causing a current to flow through the conductive portion with low electrical resistance. Loss is suppressed. However, since the connection plate is small in size, it is difficult to handle, and it is difficult to position the connection plate with respect to the terminal at the time of welding, thereby reducing workability. Further, since the connection plate is formed by a laminated structure of a plurality of materials of a nickel material and an aluminum material or a copper material, the connection plate becomes expensive and causes an increase in manufacturing cost.
[0004]
[Patent Document 1]
JP-A-2000-36299 (paragraphs 0011 to 0017, FIG. 6)
[0005]
[Problems to be solved by the invention]
Therefore, the present invention has been made in view of the above circumstances, and has a connection structure for a secondary battery that can prevent corrosion of terminals and terminal connection members and can easily and reliably connect terminals between adjacent cells. And a connection method.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, an invention according to claim 1 of the present invention is a connection structure for a secondary battery in which terminals between adjacent cells are connected by a terminal connection member. The member is plated with solder.
[0007]
According to a second aspect of the present invention, in the first aspect of the present invention, the terminal connecting member is provided with clip portions at both ends, and each clip portion is connected to each terminal.
[0008]
According to a third aspect of the present invention, in the first or second aspect of the invention, the terminal and the terminal connecting member are metal-joined.
[0009]
In order to achieve the above object, an invention according to claim 4 of the present invention is a method for connecting a secondary battery in which terminals between adjacent cells are connected by a terminal connecting member, wherein the method comprises the steps of: The member is solder-plated, each clip portion at both ends of the terminal connection member is connected to each terminal for mutual connection, and then each clip portion and each terminal are metal-joined. .
[0010]
Therefore, according to the first aspect of the present invention, the terminal and the terminal connecting member are covered with the solder plating, and the aluminum material and the copper material which are the base materials of the terminal and the terminal connecting member are not exposed. Further, corrosion of the terminal connecting member is prevented.
[0011]
According to the second aspect of the invention, connection between the terminal and the terminal connection member (positioning and mounting of the terminal connection member with respect to the terminal) becomes easy.
[0012]
According to the third aspect of the present invention, the fastening by the bolt or the nut is eliminated, and the terminal and the terminal connecting member can be easily and reliably connected.
[0013]
According to the fourth aspect of the present invention, the terminal and the terminal connection member are plated in advance with solder, and the clip portions at both ends of the terminal connection member are connected to the respective terminals to be connected to each other. By metal-joining the part and each terminal, terminals between adjacent cells are connected.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the connection structure of the present secondary battery 1 is such that terminals 3 and 4 between cells 2 (unit cells of a lithium ion secondary battery in this embodiment) arranged adjacent to each other are made of a conductor. The connection structure of the secondary battery 1 is connected in series by the terminal connection member 5, wherein both the terminals 3 and 4 of each cell 2 and the terminal connection member 5 are plated with solder, and the terminal connection member 5 The clip portions 6 at both ends are connected to the terminals 3 and 4 for connecting each other, the terminals 3 and 4 are connected to each other, and the connected terminals 3 and 4 and the clip portions 6 are ultrasonically bonded (metal By bonding, the terminals 3 and 4 between adjacent cells 2 are connected. As shown in FIG. 2, the cell 2 has a plate-like positive electrode terminal 3 and a negative electrode terminal 4 arranged on one surface of a laminated metal casing 7. As shown in FIG. 3, the casing 7 accommodates a positive electrode plate 8, a negative electrode plate 9, a separator 10, and an electrolytic solution 11.
[0015]
The positive electrode plate 8 is formed by coating a positive electrode active material in a thin layer on an aluminum substrate, and the integrally formed positive electrode terminal 3 is subjected to solder plating. The negative electrode plate 9 is formed by applying a paste of a mixture of a carbon material and a binder to a copper substrate with an organic solvent in a thin layer shape, and the integrally formed negative electrode terminal 4 is formed by solder plating. It has been subjected. The electrolytic solution 11 is an organic electrolytic solution mainly composed of a mixed solvent. For example, as a high dielectric constant solvent, ethylene carbonate (EC), propylene carbonate (PC), γ-butyrolactone (γ-BL), dimethyl sulfoxide (DMSO), and dimethyl carbonate (DMC), dimethoxyethane (DME) and the like are used as low-viscosity solvents. Further, supporting electrolytes for imparting ion conductivity to the electrolytic solution 11 include lithium hexafluorophosphate (LiPF6), lithium perchlorate (LiClO4), lithium tetrafluoroborate (LiBF4), and lithium hexafluoride. A lithium salt such as (LiAsF6) is used.
[0016]
The separator 10 is formed of a microporous film having a current blocking function, such as polyethylene or polypropylene, and has a structure that holds the electrolytic solution 11 and separates the inside of the casing 7 into a positive electrode and a negative electrode. As shown in FIG. 4, the terminal connecting member 5 is formed by connecting a pair of clip portions 6 by a connecting portion 5a. Each clip portion 6 is formed such that one side of a pair of opposing holding pieces 6a at a predetermined interval is connected by a connecting piece 6b to form a substantially U-shaped cross section, and one of a pair of opposing holding pieces 6a. The holding piece 6a is connected to the connecting piece 6b. The connecting piece 6b is formed with a terminal insertion hole 6c through which the terminals 3 and 4 are inserted and penetrated when the terminals 3 and 4 are connected. The terminal connecting member 5 is coated with solder plating on the entire surface including the clip portion 6 made of a copper base material.
[0017]
Then, as shown in FIG. 1, the connection structure of the present secondary battery 1 is configured such that the cells 2 adjacent to the terminal insertion holes 6 c of the clip portions 6 at both ends of the terminal connection member 5 are connected to each other. The terminals 3 and 4 are inserted and penetrated, and the terminals 3 and 4 are sandwiched by a pair of the holding pieces 6 a of each clip portion 6, so that the terminals 3 and 4 are connected by the terminal connecting member 5. ing. Further, the connection structure of the secondary battery 1 has a structure in which the connected terminals 3 and 4 and the clip portions 6 at both ends of the terminal connection member 5 are fixed by ultrasonic bonding (metal bonding). I have.
[0018]
Next, the operation of the present embodiment will be described. Here, a case in which a plurality of (four in the present embodiment) cells 2 (unit cells of a lithium ion secondary battery) are connected in series using the terminal connection member 5 will be described. First, as shown in FIG. 5, each cell 2 is arranged in a direction in which the positive electrode terminals 3 and the negative electrode terminals 4 are alternately arranged in the cell arrangement direction (the left-right direction as viewed in FIG. 5). Then, among the cells 2 arranged on both sides in the cell arrangement direction, the terminal connecting member 5 is connected to the positive terminal 3 of the cell 2 arranged at the right end in the paper view of FIG. 5 in which the negative terminal 4 is connected to the external negative terminal. And the other clip portion 6 of the terminal connecting member 5 is connected to the negative terminal 4 of the cell 2 arranged second from the right adjacent to the cell 2 and arranged at the right end. The positive terminal 3 of the cell 2 and the negative terminal 4 of the second cell 2 arranged from the right are connected by the terminal connecting member 5.
[0019]
Next, the positive electrode terminal 3 of the cell 2 arranged second from the right and the negative electrode terminal 4 of the cell 2 arranged third from the right in the paper view in FIG. 5 are further arranged third from the right. The positive electrode terminal 3 of the cell 2 and the negative electrode terminal 4 of the cell 2 arranged at the left end as viewed in FIG. 5 where the positive electrode terminal 3 is connected to the external positive terminal are sequentially connected by the terminal connecting member 5. Then, the clip portions 6 at both ends of each terminal connection member 5 and the terminals 3 and 4 are joined by ultrasonic joining (metal joining). As a result, as shown in FIG. 1, an assembled battery (secondary battery 1) in which four lithium ion secondary batteries (cells 2) are connected in series is configured.
[0020]
This embodiment has the following effects.
In the connection structure of the secondary battery 1, since the terminals 3 and 4 of each cell 2 and the terminal connection member 5 are plated with solder, an aluminum material (the positive electrode terminal 3) or a copper material (the negative electrode terminal 4 and the terminal The connecting member 5) does not corrode due to exposure to the outside air, and low electric resistance is maintained for a long period of time, so that stable performance as a battery can be secured.
The connection structure of the secondary battery 1 is such that the terminals 3 and 4 are connected to the terminals 3 and 4 between the adjacent cells 2 by connecting the clip portions 6 at both ends of the terminal connecting member 5 to each other. Compared with a conventional connection structure in which the terminals 3 and 4 are fastened to the terminal connection member 5, the connection between the terminals 3 and 4 and the terminal connection member 5 is facilitated, and the work efficiency of the terminal connection is improved. Becomes possible. Also, since the terminals 3 and 4 are inserted through the terminal insertion holes 6c of the clip portions 6 and penetrate the terminal connecting member 5, the clip portions 6 and the terminals 3 and 4 are securely connected. be able to. Further, in the connection structure of the present secondary battery 1, since each terminal 3, 4 is sandwiched by a pair of sandwiching pieces 6 a of each clip 6, the contact area between each terminal 3, 4 and the terminal connecting member 5 is set. And heat dissipation can be improved. Therefore, the stress of each cell 2 is reduced, and the deterioration of each cell 2 can be prevented.
In the connection structure of the secondary battery 1, the connected terminals 3 and 4 and the clip portions 6 of the terminal connection member 5 are fixed by ultrasonic bonding (metal bonding). Therefore, the connection structure of the present secondary battery 1 is different from the conventional connection structure in which the terminals 3 and 4 and the terminal connection member 5 are fastened with bolts or the like. Since the connection is easy and the bolts and the like do not loosen, the terminals 3 and 4 can be securely connected to the clip portions 6 of the terminal connecting member 5. Further, the number of parts is reduced as compared with the above-described conventional connection structure, and the manufacturing cost can be reduced. Further, since both the terminals 3 and 4 to be connected and the terminal connecting member 5 are pre-plated with solder, there is no need for flux at the time of joining by solder plating, and slag which is indispensable when flux is used. And the removal of residue can be eliminated.
[0021]
The embodiment is not limited to the above, and may be configured as follows, for example.
In the present embodiment, the connection structure of the secondary battery 1 for connecting a plurality of cells (cells 2) of the lithium ion secondary battery has been described, but the connected cells (cell 2) are lithium ion secondary cells. The present connection structure using the terminal connection member 5 is not limited to the battery, and may be adopted, for example, when an electric double layer capacitor having an intermediate capacity between the battery and the capacitor is connected.
The solder plating applied to the terminals 3 and 4 and the terminal connection member 5 of each cell 2 may be selected from Sn plating or Sn alloy plating as necessary.
The connection between each of the connected terminals 3 and 4 and each of the clip portions 6 of the terminal connection member 5 only needs to be surely performed by metal bonding. For example, resistance welding, pressure welding, soldering, and plastic fastening And so on.
[0022]
【The invention's effect】
As described above in detail, according to the present invention, a connection structure and connection of a secondary battery that can prevent corrosion of terminals and terminal connection members and can easily and reliably connect terminals between adjacent cells. A method can be provided.
[Brief description of the drawings]
FIG. 1 is a perspective view of a connection structure of the present secondary battery.
FIG. 2 is a perspective view of a single cell (lithium ion secondary battery).
FIG. 3 is a diagram showing a schematic structure of a cell (lithium ion secondary battery).
FIG. 4 is a perspective view of a terminal connection member.
FIG. 5 is a plan view showing an arrangement of cells when cells are connected in series.
[Explanation of symbols]
1 rechargeable battery 2 cells (lithium ion rechargeable battery)
3 Positive terminal 4 Negative terminal 5 Terminal connection member 6 Clip part
