JP5096842B2 - Battery storage unit - Google Patents

Description

  The present invention relates to a battery storage unit in which a plurality of battery modules are arranged in parallel in a casing and used as a power source for an electric vehicle or the like.

  As a drive power source for an electric vehicle, a battery storage unit in which a plurality of substantially cylindrical battery modules are arranged in parallel in a casing and adjacent battery modules are connected in series via a conductive connecting member is known. ing.

In this type of battery storage unit, each battery module generates heat due to charging / discharging of electricity, and therefore it is necessary to efficiently cool the battery module in order to effectively use the performance of the battery module.
For this reason, as a battery storage unit that copes with this, the housing is provided with a refrigerant inlet and outlet, the refrigerant such as air taken from the inlet is applied to the outer peripheral surface of each battery module, and the entire battery module is passed through the outer peripheral surface Has been developed (see, for example, Patent Document 1).
JP 2006-134893 A

  However, since this conventional battery storage unit mainly cools the outer peripheral surface of the battery modules in the housing with a refrigerant, it cannot be said that the cooling efficiency for each battery module is sufficient. In order to sufficiently cool the module, a large flow rate of refrigerant must be guided to the outer peripheral surface of each battery module. For this reason, in this conventional battery storage unit, it is necessary to form a refrigerant flow path having a large cross-sectional area with a sufficient space between adjacent battery modules in the casing, and avoiding an increase in size of the entire unit. I can't.

  For this reason, it is currently considered to actively induce a cooling medium to the conductive connection member that connects the electrode terminals of adjacent battery modules, and to efficiently cool each battery module via the conductive connection member and the electrode terminal. is doing. However, in this case, a plurality of battery modules are arranged in parallel in the casing, and a plurality of conductive connecting members are arranged from the upstream side to the downstream side of the flow of the cooling medium. Then, when the heat radiation area (for example, the area where the surface area is increased by bending) in the substantially central portion in the extending direction of each conductive connecting member is aligned along the flow direction of the refrigerant, it is positioned downstream of the flow of the refrigerant. The conductive connecting member is greatly affected by the heat of the upstream conductive connecting member. Therefore, the cooling performance varies from one battery module to another, making it difficult to maximize the performance of the entire battery storage unit. To avoid this, the cross-sectional area of the refrigerant flow path must be increased.

  Therefore, the present invention is intended to provide a battery storage unit that can increase the cooling efficiency of the battery module in the casing and can reduce the size of the entire unit.

The invention according to claim 1, which solves the above problem, includes a plurality of substantially cylindrical battery modules (for example, a battery module 3 in an embodiment described later) aligned in the axial direction (for example, an embodiment described later). a plurality of stages in the housing 2) within the are arranged in a plurality of rows matrix, the housing of the electrode terminals of the axial ends of the adjacent battery module (e.g., the electrode terminals 5 in the embodiment) between conductive connecting members (e.g., a bus bar 11 in the embodiment) a battery storage unit electrically connected in series via, in a region facing the end portion in the axial direction of the plurality of battery modules of the housing, refrigerant flow path (e.g., the coolant channel 17 in the embodiment) with is provided, electrically discharge the substantially intermediate portion of the extending direction of the conductive connecting member for connecting in series the electrode terminals to each other A region (for example, a bent convex portion 13 in an embodiment described later) is provided, and the conductive connecting member has electrode terminals adjacent to each other in the refrigerant flow direction in the refrigerant flow path parallel to the refrigerant flow direction. A plurality of first conductive connecting members (for example, a first bus bar 11A in an embodiment described later) and two adjacent first conductive connecting members that are bridged and connected to each other are projected in the refrigerant flow direction. A second conductive connecting member (for example, a second bus bar 11B in an embodiment described later) that connects adjacent electrode terminals at positions so as to be bridged so as to be substantially orthogonal to the flow direction of the refrigerant ; The refrigerant flow path is a sorting passage (for example, sorting in an embodiment described later) that flows through the first conductive connecting member by a refrigerant separator (for example, partition walls 20A, 20B in the embodiment described later). Path 21a) and a sorting passage (for example, sorting passage 21b in an embodiment described later) flowing through the second conductive connecting member, and each one of the sorting passages includes the first conductive connection. Only one of the member and the second conductive connecting member is provided.
As a result, the second conductive connecting member is disposed at a position where the two adjacent first conductive connecting members are projected in the flow direction of the refrigerant, so that the first conductive connecting member and the second conductive connecting member The heat radiation area does not overlap in the refrigerant flow direction.
Moreover, the area | region through which the refrigerant | coolant of a 1st conductive connection member and a 2nd conductive connection member passes comes to be divided by the refrigerant | coolant separator into an exclusive selection channel | path , respectively.

According to a second aspect of the invention, in the battery storage unit of claim 1, wherein the refrigerant separator is formed in the housing wall facing the first conductive connection member and the second conductive connection member It is characterized by.
According to a third aspect of the present invention, in the battery housing unit according to the first or second aspect, the heat dissipation region of the conductive connecting member is formed by a bent convex portion protruding outward in the axial direction of the battery module. It is characterized by that.

  According to the first aspect of the present invention, the second conductive connecting member is disposed at a position where two adjacent first conductive connecting members are projected in the flow direction of the refrigerant, and the heat dissipation area of both the conductive connecting members is provided. Since the structure does not overlap in the refrigerant flow direction, the plurality of battery modules in the housing can be cooled uniformly and efficiently, and the entire unit can be downsized.

Furthermore, according to the invention described in claim 1 , the refrigerant flow path is completely partitioned into a selection passage that passes through the first conductive connection member and a selection passage that passes through the second conductive connection member by the refrigerant separator , In addition, since each one of the sorting passages is provided with only one of the first conductive connecting member and the second conductive connecting member , the downstream conductive connecting member is connected to the upstream conductive member. The influence of the heat of the connecting member can be made more difficult, and the space dielectric breakdown distance between the different electrodes can be secured by the refrigerant separator.

According to the invention described in claim 2 , since the refrigerant separator is formed on the wall of the housing, the structure can be simplified and the product cost can be reduced.

Embodiments of the present invention will be described below with reference to the drawings. In the following description of each embodiment, the same parts are denoted by the same reference numerals, and the description of the overlapping parts is omitted.
First, a first embodiment of the present invention shown in FIGS. 1 to 4 will be described.
The battery storage unit 1 of this embodiment is used as a driving power source for an electric vehicle including a hybrid vehicle, and a plurality of battery modules 3 are arranged in parallel inside a substantially rectangular parallelepiped metal housing 2. Has been accommodated. As shown in FIG. 4, in the battery module 3, the module main body 4 is formed in a columnar shape, and one of positive and negative electrode terminals 5 is provided on both end surfaces of the module main body 4 in the axial direction. Note that in this specification, the battery module includes not only a single unit of a plurality of single cells connected in series and formed into a cylindrical shape, but also a single unit of single columnar cells.

As shown in FIG. 3, the housing 2 includes a rectangular tube-shaped housing body 6 having openings at opposite ends, a first cover 7 that closes the openings on both sides of the housing body 6, and A second cover 8 is provided, and both covers 7 and 8 are integrally coupled to the housing body 6 by bolt coupling or the like.
Here, for convenience of explanation, if the direction connecting the openings on both sides of the housing body 6 is referred to as the “opening direction”, the inner wall of the housing body 6 has a plurality of support walls 9 along the opening direction. The battery modules 3 are integrally formed and supported by the support walls 9.

The battery modules 3 are arranged in parallel in the housing body 6 so that the axial direction of each module 3 is along the opening direction of the housing body 6, and when viewed from the opening direction as shown in FIG. Are arranged in a matrix so as to be regularly aligned vertically and horizontally. In the example of this embodiment, the battery modules 3 are arranged in four rows and six rows. In the following description, when the arrangement of the battery modules 3 is described, “upper two steps”, “lower two steps”, and the like are distinguished from each other in correspondence with the illustration of FIG.
And between the battery modules 3 and 3 which adjoin each stage and each row | line | column, the holding member 10 along the opening direction of the housing body 6 is interposed. Therefore, as shown in FIG. 2, a plurality of battery modules 3... Are arranged in a grid pattern along with the above-described support walls 9 and holding members 10.
Here, the surface of each support wall 9 and the holding member 10 that contacts the outer peripheral surface of the battery module 3 is formed in an arc shape along the outer peripheral surface of the module 3, and the periphery of each battery module 3 is the holding member 10. And the support wall 9 defines four spaces 12 extending in the axial direction.

  Further, the battery modules 3 arranged inside the housing body 6 as described above are set so that the positive and negative electrodes of adjacent ones are opposite to each other, and the adjacent electrode terminals 5 and 5 are electrically conductive. They are appropriately connected by a bus bar 11 that is a connecting member. The connection of the electrode terminals 5 and 5 by the bus bar 11 is such that all the upper two battery modules 3 in the housing body 6 and the lower two battery modules 3 are connected in series. Has been done.

Bus bar 11, a conductive metal plate is formed in a cross-hat, both side edges sandwiching a central stepped bent protrusion 13 is sleep Flip Ni Accordingly coupled to an end face of the respective electrode terminals 5. The bus bar 11 is coupled to each electrode terminal 5 in a direction in which the bent convex portion 13 protrudes outward in the axial direction of the battery module 3, and the bent convex portion 13 radiates the heat of the electrode terminal 5 to the outside most. It is a heat dissipation area.

On the other hand, the first cover 7 has a ceiling wall corresponding to the shape of the end surface of the housing body 6 and a side wall corresponding to the peripheral wall of the housing body 6, and the first cover 7 has a short extension width. An inlet 15 and an outlet 16 for cooling air (cooling medium) are formed in the side wall and the other side wall opposite thereto. As shown in FIG. 1, the introduction port 15 is arranged to be biased to one side in the width direction of one side wall, and the discharge port 16 is arranged to be biased to the other side in the width direction of the other side wall. Between the inlet 15 and the outlet 16 in the body 2, a refrigerant flow path 17 through which cooling air flows is formed. In the case of this embodiment, a suction fan (not shown) is connected to the discharge port 16 via a suction duct (not shown), and the cooling air flowing in from the introduction port 15 by the drive of the suction fan is used as a refrigerant flow path. 17 and the outlet 16 are discharged to the outside of the housing 2. The refrigerant flow path 17 is mainly configured in a space surrounded by the side wall of the first cover 7, but the electrode terminals 5 and the bus bars 11 of the plurality of battery modules 3. It protrudes into the space and faces the refrigerant flow path 17.

  In the state where the first cover 7 is attached to the housing body 6, the housing 2 has an introduction side translation passage 18 extending straight forward from the introduction port 15, as shown in FIG. 1. A discharge-side translation passage 19 is formed in parallel with the introduction-side translation passage 18 and extending straight toward the discharge port 16. Cooling air introduced into the housing 2 is mainly used as the introduction-side translation passage. The flow from 18 to the discharge side translation passage 19 is substantially perpendicular.

By the way, in the case of this embodiment, the bus bars 11... Connecting the adjacent battery modules 3 on the first cover 7 side are arranged as follows.
That is, the bus bars 11 corresponding to the upper two battery modules 3 are all arranged so as to follow the flow of cooling air from the introduction side translation passage 18 to the discharge side translation passage 19, and in the cooling air flow direction. The battery modules 3 and 3 arranged adjacent to each other are bridged and connected to each other. Hereinafter, this bus bar is referred to as “first bus bar 11A” (first conductive connecting member). Also, the bus bars 11 corresponding to the lower two battery modules 3 are all arranged in a direction orthogonal to the flow of the cooling air, and are adjacently arranged in a direction orthogonal to the flow of the cooling air. , 3 are cross-linked and connected. Hereinafter, this bus bar is referred to as “second bus bar 11B” (second conductive connecting member). The first bus bar 11 A is disposed on the upper side of the stage are arranged offset in the direction perpendicular to the flow of cooling air to the second bus bar 11B arranged below the stage.
Therefore, the first bus bar 11A that connects the upper two battery modules 3 and the second bus bar 11B that connects the lower two battery modules 3 have the bent projections 13 of the cooling air. It does not overlap in the flow direction.

  Further, a plurality of partition walls 20 </ b> A,..., 20 </ b> B (refrigerant separators) projecting from the introduction-side translation passage 18 toward the discharge-side translation passage 19 project from the ceiling wall of the first cover 7. Each partition wall 20A, 20B is provided with a linear region a along the extending direction of the first bus bar 11A, and a bent region b that is bent from the linear region a and goes around the end of the second bus bar 11B. In cooperation with the partition walls 20A, 20B, etc., sorting passages 21a, 21b, ... (refrigerant passages) through which only one bus bar 11A or 11B passes the cooling air entering from the introduction side translation passage 18 are formed. Yes.

  Up to this point, the structure on the first cover 7 side has been described, but a structure substantially similar to that of the first cover is also adopted on the second cover 8 side. Here, although detailed description on the second cover 8 side is omitted, on the second cover 8 side, the second bus bars 11B... Are arranged in the upper two stages because of the connection of the adjacent battery modules 3 and 3. The first bus bars 11A are arranged in the lower two stages.

  In the above configuration, when the suction fan is driven when the battery storage unit 1 is used, the cooling air flowing into the introduction side translation passage 18 from the introduction port 15 of the housing 2 is transferred from the introduction side translation passage 18 to each sorting passage 21a. ..., 21b ... flows to the discharge side translation passage 19 and is discharged to the outside of the housing 2 through the discharge port 16. During this time, the cooling air passing through the sorting passages 21a and 21b cools one bent convex portion 13 and the electrode terminals 5 and 5 of the corresponding bus bars 11A and 11B and is discharged to the outside.

  In the battery storage unit 1, the cooling air flowing through the refrigerant flow path 17 flows in the housing 2 to the electrode terminals 5 of the battery modules 3. It is possible to efficiently cool the electrode terminal 5 and the bus bar 11 which are directly connected via a high material with cooling air. Moreover, since the cooling air flows through the surrounding space 12 on the outer peripheral surface of each battery module 3 with a small flow rate as compared with the refrigerant flow path 17, it is possible to reliably prevent heat from being accumulated inside the housing 2. be able to.

By the way, FIG. 5 shows the result of investigating the state of temperature change at the center of the battery module 3 when the electrode terminal 5 is cooled as in this embodiment and when the electrode terminal 5 is not cooled. As can be seen from the figure, when the electrode terminal 5 is cooled, the temperature of the central portion of the battery module 3 can be lowered at an early stage.
FIG. 6 shows a flow path (first refrigerant flow path) that passes through the electrode terminal 5 and a flow path (second refrigerant flow path) that passes through the outer periphery of the battery module 3 when the electrode terminal 5 is cooled. The result of having compared the relationship between the refrigerant | coolant distribution amount and cooling capacity for every terminal fastening part dimension, ie, the size of the electrode terminal 5, is shown. As is apparent from the figure, when the electrode terminal 5 is cooled, the electrode terminal 5 has a larger distribution amount to the first refrigerant channel than the second refrigerant channel, and a larger terminal fastening portion dimension. In 5, the cooling capacity can be increased.
Therefore, as in this embodiment, it is advantageous to increase the cooling efficiency for the battery module 3 by providing the bent protrusions 13 on the bus bars 11A and 11B facing the refrigerant flow path 17 to increase the size.

  Further, in the battery storage unit 1, the first bus bar 11A is arranged in parallel with the flow direction of the refrigerant air, and the second bus bar 11B on the downstream side or the upstream side with respect to the first bus bar 11A is cooled. One bus bar is disposed at right angles to the air flow direction, and the bent convex portion 13 of the first bus bar 11A and the bent convex portion 13 of the second bus bar 11B do not overlap in the refrigerant flow direction. The heat radiation of 11A (11B) does not adversely affect the cooling of the other bus bar 11B (11A). In particular, in the case of this embodiment, since the second bus bar 11B of each stage is arranged offset, the bent convex portions 13 of the two second bus bars 11B and 11B overlap in the refrigerant flow direction. There is no influence of heat dissipation. Therefore, in this battery storage unit 1, since the plurality of battery modules 3 in the housing 2 can be cooled uniformly and efficiently, the entire unit can be further downsized.

  Further, in the battery storage unit 1, the refrigerant flow path 17 in the housing 2 is divided by a plurality of sorting walls 20A, 20B, so that one passage corresponds to one bus bar 11A (11B). Since the passages 21a, 21b, etc. are partitioned, the bus bars 11A, 11B, and the electrode terminals 5 in the housing 2 can be more uniformly cooled. And since this battery storage unit 1 partitions the refrigerant | coolant flow path 17 into several selection channel | paths 21a ... 21b ... corresponding to each bus-bar 11A, 11B, it can fully ensure the space dielectric breakdown distance of different poles. There is an advantage.

  Further, in the case of this embodiment, partition walls 20A, 20B,... Project from the ceiling walls of the first and second covers 7, 8 facing the bus bars 11A, 11B, thereby sorting passages 21a, 21b. ... is constructed, so that there is an advantage that the structure can be simplified and the product cost can be reduced.

In addition, this invention is not limited to said embodiment, A various design change is possible in the range which does not deviate from the summary. For example, in the first embodiment, the battery modules 3 are arranged in four stages and six rows in the housing 2, but the arrangement of the battery modules 3 is not limited to this, and FIG. The battery modules 3 may be arranged in three stages as in the second embodiment shown in FIG. In this case, as the partition walls 120A and 120B, those having the straight region a and the bent region b and those having only the straight region a are used.
Further, in the above embodiment, the suction fan is connected to the discharge port 16 of the housing 2, but a cooling air pumping device may be connected to the introduction port 15 of the housing 2.

Sectional drawing corresponding to the BB cross section of FIG. 3 which shows 1st Embodiment of this invention. The top view of the battery storage unit which removed the cover which shows the embodiment. The fragmentary sectional view corresponding to the AA cross section of FIG. 1 which shows the same embodiment. The perspective view which arranged the some battery module which shows the same embodiment. The characteristic view which investigated the mode of the temperature change in the center part of the battery module when not cooling with the electrode terminal. The characteristic view which investigated the relationship between the size of a terminal fastening part, the flow path of a refrigerant | coolant, and cooling capacity. Sectional drawing similar to FIG. 1 which shows 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Battery storage unit 2 ... Housing 3 ... Battery module 5 ... Electrode terminal 11 ... Bus bar (conductive connection member)
11A: First bus bar (first conductive connecting member)
11B ... Second bus bar (second conductive connecting member)
13 ... Bending convexity (heat dissipation area)
17 ... Refrigerant flow path 20A, 20B, 120A, 120B ... Partition wall (refrigerant separator)
21a, 21b ... Sorting passage (refrigerant passage)

Claims (3)

A plurality of substantially cylindrical battery modules are arranged in a plurality of rows and a plurality of rows in a matrix with the axial direction aligned in the housing, and the electrode terminals at the axial ends of adjacent battery modules in the housing are electrically conductive connecting members. A battery storage unit electrically connected in series via
In the region facing the axial ends of the plurality of battery modules in the housing is provided with a refrigerant flow path for flowing the refrigerant,
Extending direction radiating region approximately midway portion of the conductive connecting member for connecting electrically in series the electrode terminals from each other are provided,
The conductive connecting member is
A plurality of first conductive connecting members that connect and connect adjacent electrode terminals along the refrigerant flow direction in the refrigerant flow path in parallel with the refrigerant flow direction;
Second conductive connection for connecting adjacent electrode terminals in positions where two adjacent first conductive connection members are projected in the refrigerant flow direction, by bridging them so as to be substantially orthogonal to the refrigerant flow direction. for example Bei and the member, the,
The refrigerant flow path is partitioned by a refrigerant separator into a sorting passage that flows through the first conductive connecting member and a sorting passage that flows through the second conductive connecting member,
Each one of the sorting passages is provided with only one of the first conductive connection member and the second conductive connection member . The battery storage unit according to claim 1 , wherein the refrigerant separator is formed on a wall of the casing facing the first conductive connecting member and the second conductive connecting member. 3. The battery storage unit according to claim 1, wherein the heat dissipation area of the conductive connecting member is formed by a bent convex portion protruding outward in the axial direction of the battery module.

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