JP2010113961A - Battery pack - Google Patents

Abstract

Provided is an assembled battery capable of ensuring insulation between heat conducting members connected to adjacent connecting members without obstructing the flow of a heat medium.
An assembled battery includes a bus bar and cooling fins. The extension portions 111 of the bus bars 11 adjacent to each other in the front-rear direction are arranged separately on the right side and the left side of the connection portion 110 with the terminals interposed therebetween. Since the cooling fins 12 are thermally connected to the extending portions 111, they are not arranged adjacent to each other in the front-rear direction as in the prior art. Therefore, a sufficient distance in the front-rear direction between the cooling fins 12 can be ensured. Therefore, insulation can be ensured without providing an insulating member extending in the left-right direction between the cooling fins 12 as in the prior art. Thereby, the insulation between the refrigerant | coolant fins 12 respectively connected to the adjacent bus bar 11 is securable, without preventing the flow of a refrigerant | coolant.
[Selection] Figure 3

Description

  The present invention relates to an assembled battery in which a plurality of batteries are electrically connected by a connecting member.

  In recent years, lithium batteries and nickel batteries having high output and high energy capacity have been put into practical use as power sources for driving automobiles. These batteries include an electrode body, a terminal, and a battery container. A plurality of them are combined and used as an assembled battery. When an assembled battery is used for driving an automobile, intense charging / discharging is repeated. For this reason, there is a possibility that the temperature rises due to the heat generation of the electrode body due to the chemical reaction, and the performance of the battery deteriorates.

Conventionally, as an assembled battery that can suppress such a temperature rise, for example, there is an assembled battery disclosed in Patent Document 1. As shown in FIG. 6, the assembled battery A is composed of a plurality of unit batteries B and a plurality of bus bars C. A pair of terminal members protrude from the upper surface of the unit battery B. The plurality of unit batteries B are arranged side by side with a pair of terminals aligned in a row. Terminal members of the unit cells B adjacent in the column direction are connected in series by a bus bar D on which cooling fins C are formed. By flowing the refrigerant in the column direction along the upper surface of the unit battery B, the heat generated in the electrode body is radiated to the refrigerant via the terminal member, the bus bar D, and the cooling fin C. Thereby, the temperature rise of the assembled battery A can be suppressed.
JP-A-2005-71674

  By the way, in the assembled battery A mentioned above, the temperature rise of the assembled battery A is suppressed by radiating the generated heat to the refrigerant. When the cooling fin C is condensed due to moisture contained in the refrigerant, or when foreign matter is mixed in the refrigerant, there is a possibility that the cooling fins C are short-circuited. Therefore, in particular, it is necessary to ensure insulation between the cooling fins C disposed adjacent to each other in the column direction. However, in order to ensure insulation between the cooling fins C, an insulating member E extending in a direction orthogonal to the column direction must be provided as shown in FIG. This greatly hinders the flow of the refrigerant, resulting in a decrease in cooling performance.

  This invention is made | formed in view of such a situation, and provides the assembled battery which can ensure the insulation between the heat conductive members respectively connected to the adjacent connection member, without disturbing the flow of a heat medium. The purpose is to do.

Means for Solving the Problems and Effects of the Invention

  Therefore, as a result of intensive studies and trial and error to solve this problem, the present inventor devised the arrangement of the heat conducting members, specifically, connected to connecting members adjacent in the column direction. Insulation between the heat conducting members is ensured without interfering with the flow of the heat medium by arranging the heat conducting members separately on one side and the other side of the terminals in the direction perpendicular to the column direction across the terminals. I came up with what I could do and came to complete the present invention.

  That is, the assembled battery according to claim 1 has a pair of terminals protruding from one surface of the battery container, and the plurality of batteries arranged in parallel in a state where the pair of terminals are arranged in a row, respectively, in the row direction. An assembled battery comprising: a connecting member that electrically connects adjacent terminals; and a heat conductive member that is thermally connected to each connecting member and that is cooled or heated by a heat medium that flows in the column direction. The heat conducting members respectively connected to the adjacent connecting members are arranged separately on one side and the other side of the terminals in a direction orthogonal to the column direction across the terminals. Here, the row direction is the direction in which the terminals are arranged in a row.

  According to this configuration, the heat conducting members are not arranged adjacent to each other in the column direction as in the conventional case. Therefore, it is possible to ensure a sufficient interval in the column direction between the heat conducting members. Therefore, insulation between the heat conducting members can be ensured without providing an insulating member extending in a direction orthogonal to the column direction between the heat conducting members as in the prior art. Thereby, the insulation between the heat conducting members connected to the adjacent connecting members can be ensured without disturbing the flow of the heat medium.

  The assembled battery according to claim 2 is the assembled battery according to claim 1, wherein the connection member extends in the column direction, and electrically connects the terminals adjacent in the column direction, and the connection unit. An extending portion extending in a direction orthogonal to the row direction, and the extending portion of the connecting member adjacent in the row direction is one of the connecting portions in the direction perpendicular to the row direction with the terminals interposed therebetween. The heat conducting member is arranged separately on the side and the other side, and the heat conducting member is thermally connected to the extending portion. According to this configuration, the heat conducting members connected to the connecting members adjacent in the column direction can be reliably arranged on one side and the other side of the terminals in the direction orthogonal to the column direction.

  The assembled battery according to claim 3 is the assembled battery according to claim 2, characterized in that the dimension in the column direction of the heat conducting member is set longer than the dimension in the column direction of the connecting portion. According to this structure, a heat conductive member can be enlarged compared with the past. Therefore, heat conduction characteristics can be improved.

  The assembled battery according to claim 4 is the assembled battery according to any one of claims 1 to 3, wherein the battery is between the pair of terminals and is adjacent to the direction perpendicular to the column direction. And a first insulating member that extends in the column direction and insulates between the heat conducting members adjacent to each other in the direction orthogonal to the column direction. According to this configuration, the first insulating member can reliably insulate between the heat conducting members adjacent in the direction orthogonal to the column direction.

  The assembled battery according to claim 5 is the assembled battery according to claim 4, wherein the first insulating member is made of resin or ceramic. According to this configuration, the insulation of the first insulating member can be ensured.

  The assembled battery according to claim 6 is the assembled battery according to any one of claims 1 to 5, and extends in the column direction between the connection portion adjacent to the direction orthogonal to the column direction and the heat conducting member. It has the 2nd insulating member which insulates between the connection part which exists and is adjacent to the direction orthogonal to a row direction, and a heat conductive member, It is characterized by the above-mentioned. According to this configuration, the second insulating member can reliably insulate between the connecting portion adjacent to the direction orthogonal to the column direction and the heat conducting member.

  The assembled battery according to claim 7 is the assembled battery according to claim 6, wherein the second insulating member is made of resin or ceramic. According to this configuration, it is possible to ensure the insulation of the second insulating member.

  The assembled battery according to claim 8 is the assembled battery according to any one of claims 1 to 7, and extends in a direction orthogonal to the column direction between connection portions adjacent to each other in the column direction. It has the 3rd insulating member which insulates between the connection parts adjacent to. According to this configuration, the third insulating member can reliably insulate between the connecting portions adjacent in the column direction.

  The assembled battery according to claim 9 is the assembled battery according to claim 8, wherein the third insulating member is made of resin or ceramic. According to this configuration, it is possible to ensure the insulation of the third insulating member.

  The assembled battery according to claim 10 is the assembled battery according to any one of claims 1 to 9, wherein the plurality of batteries are mounted on a vehicle. According to this configuration, in the assembled battery mounted on the vehicle, it is possible to ensure insulation between the heat conducting members respectively connected to the adjacent connecting members without hindering the flow of the heat medium.

  Next, the present invention will be described in more detail with reference to embodiments. In this embodiment, the example which applied the assembled battery which concerns on this invention to the assembled battery which consists of lithium ion batteries mounted in vehicles, such as a motor vehicle, is shown.

  First, the configuration of the assembled battery will be described with reference to FIGS. Here, FIG. 1 is a perspective view of the assembled battery in the present embodiment. FIG. 2 is a perspective view of the assembled battery in a state where a cover, a bus bar, a cooling fin, and an insulating member are not provided with respect to FIG. FIG. 3 is a top view of the assembled battery in a state in which no cover is provided with respect to FIG. FIG. 4 is a front view of the assembled battery. In addition, the front-back direction, the left-right direction, and the up-down direction in the figure are introduced for convenience in order to describe the assembled battery. Moreover, the white arrow in a figure shows the distribution direction of a refrigerant | coolant.

  As shown in FIG. 1, the assembled battery 1 includes a plurality of batteries 10, a bus bar 11 (connection member), a cooling fin 12 (heat conducting member), an insulating member 13 (first insulating member), and an insulating member 14. And a cover 15.

  As shown in FIG. 2, the battery 10 includes a positive electrode and a negative electrode capable of occluding and releasing lithium, and a nonaqueous electrolyte solution obtained by dissolving an electrolyte salt in a nonaqueous solvent in a rectangular parallelepiped case 100 made of aluminum. It is hermetically sealed. The positive electrode is composed of a positive electrode current collector made of aluminum and a positive electrode active material layer formed on the surface thereof. The negative electrode is composed of a negative electrode current collector made of copper and a negative electrode active material layer formed on the surface thereof. The battery 10 includes a positive terminal 101 and a negative terminal 102 which are a pair of terminals protruding upward from the upper surface of the case 100.

  The positive electrode terminal 101 is a columnar member made of a metal for electrically connecting the positive electrode to the outside. Since the positive electrode terminal 101 is welded to the positive electrode current collector, it is made of aluminum which is the same material as the positive electrode current collector. The negative electrode terminal 102 is a cylindrical member made of a metal for electrically connecting the negative electrode to the outside. Since the negative electrode terminal 102 is welded to the negative electrode current collector, it is made of copper which is the same material as the negative electrode current collector. The positive electrode terminal 101 and the negative electrode terminal 102 protrude upward from the upper surface of the case 100 with a predetermined interval in the left-right direction.

  The plurality of batteries 10 are juxtaposed in the front-rear direction with a pair of terminals aligned in a row in the front-rear direction. Here, the front-rear direction is the row direction in the present invention. These batteries 10 are arranged such that a positive electrode terminal 101 and a negative electrode terminal 102 face each other in the front-rear direction.

  As shown in FIGS. 3 and 4, the bus bar 11 is a plate-like member that is bent into a crank shape made of metal for electrically connecting the positive electrode terminal 101 and the negative electrode terminal 102 adjacent in the front-rear direction. . Specifically, it is a plate-like member made of aluminum or copper. The bus bar 11 includes a connection part 110 and an extension part 111.

  The connecting portion 110 is a rectangular plate-like portion that extends in the front-rear direction and electrically connects the positive electrode terminal 101 and the negative electrode terminal 102 adjacent to each other in the front-rear direction. The connecting portion 110 is formed with a circular hole portion into which the positive electrode terminal 101 and the negative electrode terminal 102 are fitted with a predetermined interval in the front-rear direction. The connection part 110 is welded by resistance welding, laser welding, or the like in a state where the hole part is fitted to the positive electrode terminal 101 and the negative electrode terminal 102, and is electrically and thermally connected. Alternatively, they are electrically and thermally connected by a fastening method such as bolts and nuts.

  The extending part 111 is a rectangular plate-like part that extends from the connecting part 110 in the left-right direction and thermally connects the cooling fins 12. The extension portions 111 of the bus bars 11 adjacent to each other in the front-rear direction are arranged separately on the right side and the left side of the connection portion 110 with the terminals interposed therebetween. That is, the extending portions 111 of the bus bar 11 are alternately arranged on the left and right of the connecting portion 110 in the front-rear direction.

  The cooling fins 12 are corrugated members made of metal for efficiently radiating heat. Specifically, it is a corrugated member made of aluminum or copper. The longitudinal dimension of the cooling fin 12 is set longer than the longitudinal dimension of the extending portion 111 of the bus bar 11. The cooling fins 12 are welded or brazed to the upper surface of the bus bar 11 by resistance welding, laser welding, brazing, or the like with both ends formed in a wave shape facing forward and backward, and are thermally connected.

  The insulating member 13 is a rectangular plate-shaped member for insulating between the cooling fins 12 adjacent to each other between the positive electrode terminal 101 and the negative electrode terminal 102 in the left-right direction. Specifically, it is a rectangular plate-shaped member made of an insulating resin or ceramic. The insulating member 13 is disposed on the upper surface of the case 100 between the positive terminal 101 and the negative terminal 102 and extending in the front-rear direction between the cooling fins 12 adjacent in the left-right direction.

The insulating member 14 is a plate-shaped member that is bent to insulate the connecting portions 110 and the cooling fins 12 adjacent in the left-right direction and between the connecting portions 110 adjacent in the front-rear direction. Specifically, it is a plate-like member made of an insulating resin or ceramic. The insulating member 14 includes an insulating portion 140 (second insulating member) and an insulating portion 141 (third insulating member).

  The insulating part 140 is a rectangular plate-shaped part for insulating between the connecting part 110 and the cooling fin 12 adjacent in the left-right direction. The insulating portion 140 is disposed on the upper surface of the case 100 so as to extend in the front-rear direction between the connecting portions 110 adjacent to the left-right direction and the cooling fins 12.

  The insulating part 141 is a rectangular plate-shaped part for insulating the connecting parts 110 adjacent in the front-rear direction. The insulating portion 141 is disposed on the upper surface of the case 100 so as to extend in the left-right direction between the connecting portions 110 adjacent in the front-rear direction.

  As shown in FIG. 1, the cover 15 is a plate-like member that is bent into a U shape to cover the upper surface of the battery 10 on which the bus bar 11, the cooling fins 12, and the insulating members 13 and 14 are disposed. is there. Specifically, it is a plate-like member made of an insulating resin. The cover 15 is arranged so as to cover the upper surface of the battery 10 on which the bus bar 11, the cooling fins 12, and the insulating members 13, 14 are disposed, with both ends formed in a U shape facing forward and backward. It is installed.

  Next, the cooling operation of the assembled battery will be described with reference to FIG. 1, FIG. 3, and FIG. The battery pack 1 shown in FIGS. 1, 3, and 4 is repeatedly charged and discharged with use in the vehicle. For this reason, the temperature rises due to heat generation in the battery 10. The assembled battery 1 is cooled by the refrigerant. Specifically, as shown by white arrows in FIGS. 1 and 3, the space surrounded by the upper surface of the case 100 and the cover 15 is cooled by air as a refrigerant that flows from the front toward the rear. . The refrigerant cools the extending portions 111 and the cooling fins 12 of the bus bar 11. Therefore, the heat generated inside the battery 10 that conducts the positive electrode terminal 101, the negative electrode terminal 102, and the bus bar 11 can be radiated to the refrigerant through the cooling fins 12. In this way, the assembled battery 1 is cooled.

  Finally, the effect will be described. According to the present embodiment, in the bus bar 11 adjacent in the front-rear direction, the extension part 111 is arranged separately on the right side and the left side of the connection part 110 with the terminal interposed therebetween. That is, the extending portions 111 of the bus bar 11 are alternately arranged on the left and right of the connecting portion 110 in the front-rear direction. The cooling fin 12 is thermally connected to the extending portion 111. Therefore, the cooling fins 12 are separately disposed on the right side and the left side of the terminal. That is, the cooling fins 12 are alternately arranged on the left and right sides of the terminal in the front-rear direction, and are not arranged adjacent to each other in the front-rear direction as in the prior art. Therefore, a sufficient distance in the front-rear direction between the cooling fins 12 can be ensured. Therefore, insulation can be ensured without providing an insulating member extending in the left-right direction between the cooling fins 12 as in the prior art. Thereby, in the assembled battery 1 mounted on the vehicle, it is possible to ensure insulation between the refrigerant fins 12 respectively connected to the adjacent bus bars 11 without disturbing the flow of the refrigerant.

  Further, according to the present embodiment, the longitudinal dimension of the cooling fin 12 is set longer than the longitudinal dimension of the extending portion 111 of the bus bar 11. Therefore, the cooling fin 12 can be enlarged compared with the past. Accordingly, the cooling characteristics can be improved.

  In addition, according to the present embodiment, the insulating member 13 can reliably insulate the cooling fins 12 between the positive electrode terminal 101 and the negative electrode terminal 102 and adjacent in the left-right direction.

  Furthermore, according to the present embodiment, the insulating member 14 can reliably insulate the connection portions 110 and the cooling fins 12 adjacent in the left-right direction and the connection portions 110 adjacent in the front-rear direction. . Here, the insulating portion 141 extends in the left-right direction orthogonal to the refrigerant flow direction, but since the left-right dimension is small, the flow of the refrigerant is hardly hindered. When the influence is further reduced, the vertical dimension may be reduced as long as insulation can be secured.

  In addition, according to the present embodiment, the insulating members 13 and 14 are made of an insulating resin or ceramic. Therefore, insulation can be ensured.

  In the present embodiment, an example in which the front-rear dimension of the cooling fin 12 is set longer than the front-rear dimension of the extending portion 111 of the bus bar 11 is described, but the present invention is not limited to this. In FIG. 3, the dimension of the extending part 111 in the front-rear direction may be longer than the dimension of the connection part 110 in the front-rear direction, and may be equal to the dimension of the cooling fin 12 in the front-rear direction. For example, as shown in FIG. 5, the dimension in the front-rear direction of the cooling fin 12 ′ may be equal to the dimension in the front-rear direction of the extending portion 111 of the bus bar 11.

  In the present embodiment, the bus bar 11 and the cooling fin 12 are made of aluminum or copper. However, the present invention is not limited to this. The bus bar 11 and the cooling fin 12 may be made of other materials. The material is not limited.

  Moreover, although the example which used air as a refrigerant | coolant is given in this embodiment, it is not restricted to this. The refrigerant may be a gas other than air. It may also be a liquid.

  Furthermore, in this embodiment, although the example which cools an assembled battery with a refrigerant | coolant is given, it is not restricted to this. The assembled battery may be heated with a heat medium having a high temperature to adjust the temperature.

  In addition, in this embodiment, the example of the assembled battery which consists of a lithium ion battery is given, However, It is not restricted to this. It may be an assembled battery composed of other secondary batteries.

It is a perspective view of the assembled battery in this embodiment. FIG. 2 is a perspective view of the assembled battery in a state in which a cover, a bus bar, a cooling fin, and an insulating member are not provided with respect to FIG. 1. FIG. 2 is a top view of the assembled battery in a state where no cover is provided with respect to FIG. 1. It is a front view of an assembled battery. It is a top view of the assembled battery in the state in which the cover in another embodiment is not arrange | positioned. It is a top view of the conventional assembled battery. It is a top view at the time of providing the insulating member in the conventional assembled battery.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Battery assembly, 10 ... Battery, 100 ... Case, 101 ... Positive electrode terminal, 102 ... Negative electrode terminal, 11 ... Busbar (connection member), 12, 12 '... Cooling fins (heat conducting members), 13 ... insulating members (first insulating members), 14 ... insulating members, 140 ... insulating portions (second insulating members), 141 ... insulating portions (third) Insulating member), 15 ... Cover

Claims (10)

A plurality of batteries having a pair of terminals protruding from one surface of the battery container, and arranged in parallel in a state in which the pair of terminals are aligned in a row;
A connecting member for electrically connecting the terminals adjacent in the column direction;
A heat conduction member that is thermally connected to each of the connection members and is cooled or heated by a heat medium flowing in a row direction;
In an assembled battery with
The heat conducting members respectively connected to the connecting members adjacent in the column direction are arranged separately on one side and the other side of the terminals in a direction orthogonal to the column direction with the terminals interposed therebetween. A battery pack characterized by. The connection member extends in a row direction, and electrically connects the terminals adjacent in the row direction, and an extension portion that extends from the connection portion in a direction perpendicular to the row direction. Have
The extending portions of the connecting members adjacent in the column direction are arranged separately on one side and the other side of the connecting portion in a direction orthogonal to the column direction across the terminals,
The assembled battery according to claim 1, wherein the heat conducting member is thermally connected to the extending portion.   The assembled battery according to claim 2, wherein a dimension in the column direction of the heat conducting member is set longer than a dimension in the column direction of the connection portion.   Between the pair of terminals, extending in the column direction between the heat conductive members adjacent in the direction orthogonal to the column direction, and insulating between the heat conductive members adjacent in the direction orthogonal to the column direction The assembled battery according to claim 1, further comprising a first insulating member.   The assembled battery according to claim 4, wherein the first insulating member is made of resin or ceramic.   Extends in the column direction between the connection part adjacent to the direction orthogonal to the column direction and the heat conduction member, and insulates between the connection part adjacent to the direction orthogonal to the column direction and the heat conduction member The assembled battery according to claim 1, further comprising a second insulating member.   The assembled battery according to claim 6, wherein the second insulating member is made of resin or ceramic.   The third insulating member that extends in a direction orthogonal to the column direction between the connection portions adjacent to each other in the column direction and that insulates between the connection portions adjacent to each other in the column direction. 8. The assembled battery according to any one of 7 above.   The assembled battery according to claim 8, wherein the third insulating member is made of resin or ceramic.   The assembled battery according to claim 1, wherein the plurality of batteries are mounted on a vehicle.

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