JP3691260B2 - Assembled battery and its connected body - Google Patents

Description

【００２４】
即ち、実施の形態に係る組電池は、重量エネルギー密度が比較組電池よりも３Wh/kg分改善されたこととなる。
図６は、上記した組電池を複数組（本例では２組）接続してなる組電池の連結体を示す。本図に示すように、当該組電池の連結体は、組電池１と組電池２が、終端電極端子１５ｄ，１５ｆ，１５０ｄ，１５０ｆが全てほぼ一直線上に並び、かつ、組電池１，２の被覆ケース側面が接するように配置され、両組電池の直近の終端電極端子１５ｆと１５０ｄとが、図４に示すのと同種の接続体１９０で接続された構成をしている。
【００２５】
各組電池の終端電極端子が存在する被覆ケースのコーナ部分が陥没されているので、接続体による接続が容易に行え、かつ、両端子間を最短の距離で接続することができるので、接続体を短くでき、連結体の全体の重量の軽減が図られる。
また、組電池本体において、同じ段の両端に位置する単電池の同じ側にある電極端子を終端電極としているので、誤って、同極性の端子同士が接続されるといった事態が回避できるという効果を奏する。この効果は、並行に配列された単電池を奇数段に積み、当該段の真ん中の段を、終端電極端子を取り出す段に選択しない限り得られる。
【００２６】
なお、上記実施の形態では、４本の単電池を２段に積んで構成したが、一段当たりの単電池の数及び段数はこれに限定されるものではない。
また、上記実施の形態では、単電池にリチウム二次電池を用いたが、単電池に用いる電池はこれに限られないことは言うまでもなく、他の種類の二次電池や一次電池であってもかまわない。
【００２７】
さらに、上記実施の形態では、２組の組電池で連結体を構成したが、連結体を構成する組電池の数はこれに限らず、３組以上用いてもよい。
また、上記実施の形態では、被覆ケースを４個の部品に分割して構成したが、分割数はこれに限らない。例えば、台座や天板のリブ部分を別体とし、接着剤等で接合するようにしてもよい。
【００２８】
【発明の効果】
以上説明したように、本発明に係る組電池によれば、終端電極を露出させており、これから直接電力を取り出すこととしているので、従来のように終端電極端子にさらに電力を取り出すための端子を取り付けたものと比較して重量の軽減が図られ、もってエネルギー密度が向上する。
【００２９】
また、終端電極が存在する被覆ケースのコーナ部分が陥没されているので、組電池同士を直列接続するに際し、接続体による終端電極間の接続が容易になり、また、両組電池の被覆ケース側面が接するように配置することで、接続体による接続距離が最短になり、接続体を短くできる分、重量の軽減が図れる。
さらに、終端電極の突出端が、当該終端電極が露出されている被覆ケースの陥没部間に存在する被覆ケースの端面位置よりも、電池軸方向に後退させているので、両終端電極間を導電体で直線的に接続することができなくなり、不測の短絡を防止することができる。
【図面の簡単な説明】
【図１】実施の形態に係る組電池を構成する単電池の概略構成を示す斜視図である。
【図２】実施の形態に係る組電池の本体の概略構成を示す斜視図である。
【図３】実施の形態に係る組電池の概略構成を示す外観斜視図である。
【図４】上記組電池本体に使用する接続体の概略構成を示す斜視図である。
【図５】実施の形態に係る組電池の被覆ケースの概略構成を示す分解斜視図である。
【図６】実施の形態に係る組電池の連結体の概略構成を示す外観斜視図である。
【図７】従来の組電池の概略構成を示す斜視図である。
【符号の説明】
１１、１２、１３、１４、１５、１６、１７、１８ 単電池
１５ｄ、１８ｆ、１５０ｄ、１８０ｆ 終端電極端子
１９ 接続体
３０ 被覆ケース
３４ｄ，３４ｅ 陥没部
１９０ 接続体[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an assembled battery and a connected body thereof, and more particularly, to a technique for improving weight energy density.
[0002]
[Prior art]
An assembled battery is a battery in which a plurality of single cells are connected in series, and is therefore used in devices that require high power.
FIG. 7 shows a schematic configuration of an example of a conventional assembled battery. As shown in the figure, the assembled battery is composed of eight unit cells 101 to 108 in which four unit cells are stacked side by side, and these unit cells are connected to seven units. The bodies 109 to 115 are connected in series. Module terminals 116 and 117 are connected to the terminal electrodes 101 a and 104 a of the cells connected in series, and the whole is housed in a case 118.
[0003]
In this type of assembled battery, one having a large capacity of several tens of kilograms is manufactured. In recent years, in particular for electric vehicles that are attracting attention from the viewpoint of environmental problems, energy problems, etc. About 20 connected ones are installed.
[0004]
[Problems to be solved by the invention]
In an electric vehicle, the mileage that can be performed by one charge varies depending on the weight of the entire vehicle. In the above case, a slight increase in the weight of each assembled battery cannot be ignored. That is, it is desired to improve the weight energy density of the assembled battery.
An object of this invention is to provide the assembled battery which reduced the weight and improved the weight energy density in view of said subject, and the coupling body of the said assembled battery.
[0005]
[Means for Solving the Problems]
To achieve the above object, an assembled battery according to the present invention, the electrodes possess at both axial ends, the power generation element a cylindrical outer can and both end opening in a space surrounded by the sealing lid for sealing The unit cells that are housed and the electrodes project from the end face of the sealing lid are arranged in parallel in the axial direction to form a battery row, and a plurality of the battery rows are stacked to cover the entire stack. In the assembled battery in which the stored unit cells are electrically connected in series, the electrodes on the same side of the unit cells located at both ends of the same stage are used as the end electrodes of the series connection. The corner portion of the covering case where the terminal electrode is present is depressed, the terminal electrode is exposed in the depressed portion, and the protruding end of the terminal electrode is positioned from the end surface position of the covering case existing between the two depressed portions. Also the battery axial direction Have retracted, the cover case is characterized by covering the whole stack, except the terminating electrode side end portion of the unit cell having the terminating electrode.
[0006]
Further, the assembled battery assembly according to the present invention includes a plurality of the assembled batteries arranged such that all the termination electrodes are arranged substantially in a straight line and the side surfaces of the covering cases of the adjacent assembled batteries are in contact with each other. The terminal electrodes nearest to the battery are connected by a conductive connector.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of an assembled battery according to the present invention will be described with reference to the drawings.
FIG. 1 is an external perspective view of an assembled battery body, FIG. 2 is an assembled battery body, and FIG. 3 is an external perspective view of the assembled battery.
As shown in FIG. 2, the assembled battery has a structure in which four cells arranged in a horizontal row are stacked in two stages, and the entire assembled battery main body is formed by connecting these single cells in series. As shown in FIG. 3, the cover case 30 is accommodated.
[0008]
The unit cell is a lithium secondary battery, and, as shown in FIG. 1, a sheet-like separator is formed in a space surrounded by a cylindrical outer can 11a and sealing lids 11b and 11c that seal openings at both ends. Is composed of a spirally wound element sandwiched between a sheet-like positive electrode and a negative electrode, and a power generation element composed of an electrolytic solution.
A positive terminal 11d and a safety valve 11e are attached to the sealing lid 11b, and a male screw is formed on the positive terminal 11d.
[0009]
The sealing lid 11c is provided with a negative terminal 11f formed with a male screw and a safety valve (11g), and has an appearance similar to that of the positive terminal.
Reference numeral 11h denotes an electrode terminal attachment nut for attaching the positive electrode terminal 11d to the sealing lid 11b, and the negative electrode terminal 11f is similarly attached to the sealing lid 11c by the electrode terminal attachment nut.
[0010]
In addition, the single battery 10 is used such that the outer diameter φD of the outer can 11a is 64 mm, and the length L1 between the end faces of the sealing lid 11b and the sealing lid 11c is 294 mm.
The assembled battery body is composed of the same eight cells as described above.
As shown in FIG. 2, the assembled battery body includes four unit cells 15, which are arranged in the same manner on the four unit cells 11, 12, 13, 14 arranged in parallel in the axial direction. It is a two-stage structure in which 16, 17, 18 are stacked. The adjacent cells in each stage are arranged so that those of different polarities are on the same side, and the cells adjacent in the vertical direction are also arranged so that those of different polarities are on the same side. Since it is set as such an arrangement | sequence, a serial connection is attained by connecting the electrode terminal of an adjacent single cell one after another.
[0011]
For this connection, a connection body 19 as shown in FIG. 4 is used. As shown in this figure, the connection body 19 is configured by inserting and fixing a copper cap 19b at both ends of a nickel stranded wire 19a, and an electrode terminal insertion hole 19c is opened in the cap 19b. Yes.
Returning to FIG. 2, in the connection body 19, the positive terminal of one unit cell to be connected to one electrode terminal insertion hole 19c is inserted, and the negative terminal of the other unit cell is inserted into the other electrode terminal insertion hole 19c. In this state, it is fixed and attached by the connecting body mounting nut 20. That is, the cap portion of the connection body 19 is sandwiched between the electrode terminal mounting nut and the connection body mounting nut.
[0012]
Further, the connecting bodies 19 are attached so that the unit cells 15 and 18 located at both ends of the upper stage in the upper and lower stages become series termination batteries. Therefore, in this case, the positive electrode terminal 15d of the unit cell 15 and the negative electrode terminal 18d of the unit cell 18 serve as a terminal electrode connected in series. Hereinafter, the positive electrode terminal 15d and the negative electrode terminal 18f may be particularly referred to as termination electrode terminals.
[0013]
FIG. 5 is an exploded perspective view of the covering case 30 that houses the assembled battery main body configured as described above. As shown in the figure, the covering case 30 is composed of a pedestal 31, a top plate 32, a back plate 33, and a front plate 34, and any material is polycarbonate which is a non-conductive material. In addition, although the several convex part (many substantially rectangular part drawn by FIG. 3) is provided in the surface which appears on a table | surface in an assembly state, it is abbreviate | omitting in this figure.
[0014]
The pedestal 31 mainly holds the lower cells 11 to 14 (FIG. 2), and is provided with ribs 31a, 31b, and 31c. These ribs 31a, 31b, and 31c support the unit cells 11 to 14 at three places in the longitudinal direction (both ends and the center). The portion of each rib 31a to 31c that contacts the unit cell matches the outer shape of the unit cell, and the cross-section has an arc shape that is substantially equal to the outer diameter of the unit cell. Is done. The length L2 shown in the drawing of the pedestal 31 is substantially equal to the above-described length L1 of the unit cell, and each unit cell has an end surface 31d, an end surface of the pedestal 31 shown in FIG. It is mounted so that it is substantially aligned with 31e (so-called flush).
[0015]
The top plate 32 mainly holds the upper unit cells 15 to 18 (FIG. 2), and similar ribs 32 a to 32 c are provided at positions corresponding to the ribs 31 a to 31 c of the pedestal 31. As a result, the upper unit cells 15 to 18 are accommodated without rattling.
The back plate 33 covers the connection part of the battery pack main body as shown in FIG. 2 on the back side of the drawing sheet, and the portion protruding from the end face of the sealing lid of the unit cell (electrode terminal, connection body, etc.) The back plate 33 is housed in the recess 33a.
[0016]
The front plate 34 is for covering the connecting portion of the assembled battery body on the front side of the paper shown in FIG. 2 and exposing the terminal electrode terminals 15d and 18f to the outside of the covering case.
A portion (electrode terminal, connection body, etc.) protruding from the end face of the sealing lid of the cells 11 to 14, 16 and 17 (see FIG. 2) is housed in the concave portion 34a having a mountain-like cross section. The
[0017]
On the other hand, the termination electrode terminals 15d and 18f are exposed to the outside of the covering case through the termination electrode terminal insertion holes 34b and 34c provided in the front plate 34. That is, when the covering case is assembled, as seen from the entire covering case, the corner portion of the covering case where the terminal electrode terminal exists is depressed, and the terminal electrode terminal is exposed at the depressed portions 34d and 34e. is there. In addition, in the state which attached the said front plate 34 to the base 31, the thickness t1 of the part shown in the figure of the front plate 34 is the extent that the end surface of the electrode terminal attachment nut of a single cell protrudes from a termination electrode terminal insertion hole slightly. The length t <b> 2 of the entire front plate 34 is set to such a thickness that the protruding end of the terminal electrode terminal recedes from the end surface position of the front plate 34.
[0018]
In the covering case 30 having the above configuration, first, the assembled battery main body shown in FIG. In this case, the cells 11 to 18 may be arranged on the pedestal 31 and then connected by the connecting bodies 19.
Next, the top plate 32 is placed on the pedestal 31 and fixed with six screws. With the top plate attached to the pedestal 31, the back plate 33 and the front plate 34 are fixed with six screws, respectively.
[0019]
When assembled as described above, the assembled battery has dimensions of height H = 135 mm, width W = 264 mm, and depth L3 = 352 mm, as shown in FIG.
As shown in this figure, since the protruding ends of the termination electrode terminals 15d and 18f are set back from the end face 34f of the covering case 30, an unexpected short circuit between the termination electrode terminals 15d and 18f can be prevented. . That is, by making a part of the covering case exist between the terminal electrode terminals 15d and 18f, it becomes impossible to linearly connect between both terminals with a conductor. No matter how you inadvertently place it on something, it will not cause a short circuit.
[0020]
Further, since the terminal terminals 15d and 18f are not attached with module terminals like the conventional assembled battery shown in FIG. 7 (because they are in an exposed state), the weight is reduced accordingly. That is, the electrode terminal of the single cell is directly used as a terminal for taking out current from the assembled battery, thereby reducing the weight.
Here, the comparison of the weight energy density (Wh / kg) between the conventional assembled battery shown in FIG. 7 (hereinafter referred to as “comparative assembled battery”) and the assembled battery according to the embodiment shown in FIG. went. In addition, the cell used for the comparative assembled battery is the same as that used for the assembled battery according to the embodiment. The weight of the assembled battery according to the embodiment was 21.0 kg, and the weight of the comparative assembled battery was 21.5 kg.
[0021]
The capacity of the assembled battery is measured by constant current charging / discharging. During charging, a constant current of 10 A is supplied until the voltage reaches 33.6 V (each cell is 4.2 V), and during discharging, 8. The battery was discharged at 8 A until the voltage reached 21.6 V (each cell was 2.7 V).
As a result, the battery pack according to the embodiment had an average voltage of 28.8 V and a discharge capacity of 80 Ah. That is, the discharge power was 2300 Wh, and the weight energy density obtained by dividing this by the weight of the assembled battery was 110 Wh / kg.
[0022]
On the other hand, the discharge capacity (discharge power) of the comparative assembled battery was the same value as that of the assembled battery according to the embodiment, but 107 Wh / kg was obtained as the weight energy density calculated from this and the assembled battery weight. It was.
A summary of the above results is shown in Table 1.
[0023]
[Table 1]

[0024]
In other words, the assembled battery according to the embodiment has a weight energy density improved by 3 Wh / kg as compared with the comparative assembled battery.
FIG. 6 shows an assembly of battery packs formed by connecting a plurality of battery packs (two in this example). As shown in the figure, the assembled battery is composed of the assembled battery 1 and the assembled battery 2, in which the terminal electrode terminals 15d, 15f, 150d, and 150f are all aligned on a straight line. Arranged so that the side surfaces of the covering case are in contact with each other, the terminal electrode terminals 15f and 150d closest to each of the assembled batteries are connected by the same type of connecting body 190 as shown in FIG.
[0025]
Since the corner portion of the covering case where the terminal electrode terminal of each assembled battery exists is depressed, the connection body can be easily connected, and both terminals can be connected at the shortest distance. The overall weight of the coupled body can be reduced.
Moreover, in the assembled battery body, since the electrode terminals on the same side of the unit cells located at both ends of the same stage are used as the termination electrodes, it is possible to avoid the situation that the terminals of the same polarity are erroneously connected to each other. Play. This effect can be obtained unless the cells arranged in parallel are stacked in an odd number of stages and the middle stage is selected as a stage for taking out the termination electrode terminal.
[0026]
In the above embodiment, four unit cells are stacked in two stages, but the number of unit cells per stage and the number of stages are not limited thereto.
Moreover, in the said embodiment, although the lithium secondary battery was used for the single battery, it cannot be overemphasized that the battery used for a single battery is not restricted to this, Even if it is another kind of secondary battery and a primary battery. It doesn't matter.
[0027]
Furthermore, in the said embodiment, although the coupling body was comprised with two sets of assembled batteries, the number of the assembled batteries which comprise a coupling body is not restricted to this, You may use 3 or more sets.
In the above embodiment, the covering case is divided into four parts, but the number of divisions is not limited to this. For example, the pedestal and the rib portion of the top plate may be separated and joined with an adhesive or the like.
[0028]
【The invention's effect】
As described above, according to the assembled battery according to the present invention, the termination electrode is exposed, and power is directly taken out from the termination electrode. Therefore, a terminal for further extracting power from the termination electrode terminal as in the past is provided. The weight is reduced compared to the attached one, and the energy density is improved.
[0029]
In addition, since the corner portion of the covering case where the termination electrode exists is depressed, when connecting the battery packs in series, the connection between the terminal electrodes is facilitated by the connecting body, and the side surfaces of the coating case of the battery packs By arranging so as to contact each other, the connection distance by the connection body becomes the shortest and the connection body can be shortened, so that the weight can be reduced.
Furthermore, since the protruding end of the termination electrode is set back in the battery axial direction with respect to the position of the end surface of the coating case existing between the depressions of the coating case where the termination electrode is exposed, the conductive electrode is electrically connected between the two termination electrodes. It becomes impossible to connect linearly with the body, and an unexpected short circuit can be prevented.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a schematic configuration of a unit cell constituting an assembled battery according to an embodiment.
FIG. 2 is a perspective view showing a schematic configuration of a main body of the assembled battery according to the embodiment.
FIG. 3 is an external perspective view showing a schematic configuration of the assembled battery according to the embodiment.
FIG. 4 is a perspective view showing a schematic configuration of a connection body used in the assembled battery main body.
FIG. 5 is an exploded perspective view showing a schematic configuration of a cover case of the assembled battery according to the embodiment.
FIG. 6 is an external perspective view showing a schematic configuration of a battery pack assembly according to the embodiment.
FIG. 7 is a perspective view showing a schematic configuration of a conventional assembled battery.
[Explanation of symbols]
11, 12, 13, 14, 15, 16, 17, 18 Cell 15d, 18f, 150d, 180f Termination electrode terminal 19 Connection 30 Covering case 34d, 34e Depression 190 Connection

Claims (2)

Have a electrode in the axial direction at both ends, the power generation element a cylindrical outer can and both end opening in a space surrounded by the sealing lid for sealing is accommodated, said electrode from an end face of the sealing lid is provided to protrude The battery cells are arranged in parallel in the axial direction to form a battery array, and a plurality of battery arrays are stacked so that the entire stack is stored in the covering case, and the stored single cells are electrically In battery packs connected in series,
The electrodes on the same side of the unit cells located at both ends of the same stage, the termination electrode of the series connection,
The corner portion of the covering case where the termination electrode exists is depressed, the termination electrode is exposed in the depression, and the protruding end of the termination electrode is located at the end surface position of the covering case existing between the two depressions. Is retreating in the direction of the battery axis,
The battery case is characterized in that the covering case covers the entire stack except for the end portion on the terminal electrode side of the unit cell having the terminal electrode. A plurality of assembled batteries according to claim 1 , all termination electrodes are arranged in a substantially straight line, and arranged so that the side surfaces of the covering cases of adjacent assembled batteries are in contact with each other,
An assembled battery coupling body, characterized in that the terminal electrodes closest to adjacent battery packs are connected to each other with a conductive connecting body.

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