JP6134157B2 - Battery pack - Google Patents

Description

  The present invention relates to a battery pack that accommodates a plurality of battery modules including a plurality of single cells.

A battery pack that accommodates a plurality of battery modules composed of a plurality of battery cells (single cells) is required to be strong against impact and to be sealed against water, for example. In particular, in a mobile battery pack structure in which the usage environment of battery cells is easily changed, a highly sealed and robust one is required to prevent the battery cells in the battery pack from being affected by the surrounding environment. Yes.
For example, Patent Document 1 describes a battery case for realizing a strong and highly airtight battery pack.

JP 2011-124101 A

However, even when the battery case as described above is used to improve the sealing performance, liquids such as water may enter the battery case in a high humidity environment or in the rain. It is difficult to sufficiently eliminate the effects of. Similarly, even when the temperature cycle is severe, such as when the temperature inside the battery pack is repeated from a high temperature state to a low temperature state, condensation occurs inside the battery pack and is affected by water.
Thus, if water accumulates inside the battery pack, for example, the battery cell may come into contact with the conductive material of the exterior structure and corrode the battery cell.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a battery pack that can suppress the influence of water inside the battery pack and that the single cell is less likely to corrode. .

In order to achieve the above object, the present invention provides the following means.
In the battery pack of the present invention, a plurality of unit cells are arranged, a battery module in which side surfaces of the plurality of unit cells parallel to the arrangement direction are aligned on the same plane, and a plurality of the battery modules are placed side by side. A lower plate that protrudes upward from the lower plate, contacts a side surface of the battery module along the plane from the outside, and is formed on the pressing plate and passes through a region that contacts the side surface of the battery module. a through hole, even on the lower plate, wherein the battery module is provided outside the region arranged to have a, a drain hole which penetrates the lower plate, the lower plate portion of the through hole It is characterized by having reached .

  According to the above configuration, since the drain hole is formed in the lower plate, a liquid such as water caused by condensation or the like can be discharged to the outside of the battery pack. Further, since the through hole is formed in the pressing plate, the liquid discharged from between the single cells can be discharged from the through hole while positioning the battery module. Thereby, the influence of the water inside a battery pack can be suppressed, and the battery pack structure where a single cell cannot corrode easily can be formed.

  In the battery pack, the battery module preferably includes the plurality of single cells arranged along a bottom plate member.

  According to the above configuration, since the liquid such as water caused by condensation in the battery module can be smoothly discharged along the bottom plate member to the outside of the battery pack, the battery pack is further resistant to corrosion. A structure can be formed.

  In the battery pack, the battery pack includes a restriction plate protruding from the bottom plate member at a position included in the flat surface, and a second through hole provided in the restriction plate, the pressing plate being in contact with the restriction plate, The through hole is preferably provided in a region in contact with the regulation plate.

  According to the said structure, while the displacement to the width direction of a cell is controlled by a control board, the water in a battery module can be discharged | emitted outside the battery module via a through-hole and a 2nd through-hole.

  In the battery pack, the battery pack has a guide plate that continuously protrudes upward from the lower plate and partitions between one battery module arranged on the lower plate and another adjacent battery module, Preferably, water is guided from the battery module to the drain hole.

  According to the said structure, it can prevent that the water on a lower board stays in the inside of a battery pack because a guide board guides the water on a lower board to a drainage hole.

  ADVANTAGE OF THE INVENTION According to this invention, the influence of the water inside a battery pack can be suppressed, and the battery pack structure where a cell is hard to corrode can be formed.

1 is a perspective view of a battery pack according to an embodiment of the present invention. It is a perspective view of the battery pack of the state which removed the cover. It is a perspective view of the lower board structure seen from the upper part. It is a perspective view of the lower board structure seen from the lower part. It is a perspective view of the pressing plate of the embodiment of the present invention. It is a perspective view explaining the effect | action of the pressing plate of embodiment of this invention. It is a perspective view of the drain hole of the embodiment of the present invention. It is a perspective view of the battery module in the embodiment of the present invention. It is a perspective view which shows the support plate of a battery module. It is the perspective view which expanded the lower part of the single cell which a support plate supports. It is a fragmentary sectional view which shows the contact state of the insulating member and support plate which are arrange | positioned between single cells. It is sectional drawing which follows the AA line of the said FIG. It is a top view explaining the effect | action of the battery pack of embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
As shown in FIGS. 1 and 2, the battery pack 1 of this embodiment includes a lower plate structure 2 that forms a basic structure, and a plurality of (12 in this embodiment) mounted on the lower plate structure 2. The battery module 3 and a cover 50 that covers the plurality of battery modules 3 are included as main components.

  The lower plate structure 2 has a length in one direction, and is a base on which a plurality of battery modules 3 can be placed in an aligned state. As shown in FIGS. 3 and 4, the lower plate structure 2 includes a frame portion 53 in which a plurality of channel steels 54 (channels) are combined in a lattice shape, and a side plate joined to the side surface of the frame portion 53 by, for example, welding. 55 and a plate-like lower plate 4 joined to the upper surface of the frame portion 53. A plurality of frame holes 56 are formed in the lower surface of each channel steel 54.

The lower plate 4 is formed of, for example, a stainless steel plate and is a plate-like member on which a plurality of battery modules 3 are placed. In the present embodiment, the lower plate 4 is large enough to be placed in a state where 12 battery modules 3 are aligned. It is said. FIG. 3 shows an arrangement space S in which the battery module 3 is arranged. In the following description, it is assumed that 12 battery modules 3 are arranged for simplification of description.
A rectangular hole 58 for reducing the weight of the lower plate 4 is formed at a location corresponding to each arrangement space S of the lower plate 4.

  The battery module 3 has a box shape having a length in one direction, the longitudinal direction of the lower plate structure 2 and the longitudinal direction of the battery module 3 are matched, and the longitudinal direction of the lower plate structure 2 is 3 Four battery modules 3 are regularly arranged in a matrix in the direction orthogonal to the longitudinal direction. That is, in the lower plate structure 2, 12 battery modules 3 can be arranged in a 3 × 4 arrangement, and 12 arrangement spaces S are formed. The shape of the arrangement space S in plan view (the shape seen from above) corresponds to the shape of the battery module in plan view.

  As shown in FIG. 8, the battery module 3 includes an assembled battery 11 in which a plurality of unit cells 10 are arranged in a row in the thickness direction. The battery module 3 includes a casing 13 that houses the assembled battery 11. The casing 13 includes a support plate 30 (bottom plate member) that supports the assembled battery 11 from below. The support plate 30 restricts the displacement of the assembled battery 11 in the width direction, and the side surface 10 a of the unit cell 10 is aligned on the same plane by the support plate 30.

  The support plate 30 has a structure in which water caused by condensation or the like is discharged to the outside in the width direction by the support plate 30 and can be prevented from accumulating between the adjacent single cells 10. That is, the battery module 3 has a structure in which water due to condensation is discharged and the water flows to the lower plate 4 on which the battery module 3 is placed. The detailed structure of the battery module 3 will be described later.

  The side plate 55 is a plate-like member attached to the four sides of the frame portion 53 so that its main surface is orthogonal to the lower plate 4. In other words, the side plate 55 is provided so as to surround the four sides of the lower plate 4. A plurality of side plate holes 57 used for fixing the cover 50 are formed in the side plate 55.

Each placement space S is provided with a pressing plate 5 for positioning the battery module 3. As shown in FIG. 5, the holding plate 5 is a plate-like member provided so as to protrude upward from the upper surface of the lower plate 4, and is perpendicular to the lower plate 4 and is in contact with the longitudinal direction of the lower plate structure 2. A contact portion 59 is provided. That is, as shown in FIG. 6, when the battery module 3 abuts against the abutment portion 59 of the holding plate 5, the positioning of the lower plate structure 2 of the battery module 3 in the direction along the short side (width direction) is performed. To be done. A support plate 30 of the battery module 3 to be described later contacts the contact portion 59.
The holding plate 5 of the present embodiment is disposed so as to abut on the approximate center of the battery module 3 in the longitudinal direction. The pressing plate 5 is not limited to one for each arrangement space S, and a plurality of pressing plates 5 may be provided.

In addition, the pressing plate 5 has a reinforcing portion 60 that bends to the opposite side of the surface of the contact portion 59 where the battery module 3 contacts. The reinforcing portion 60 is bent to the opposite side of the battery module 3 so as not to interfere with the battery module 3 when the battery module 3 contacts the contact portion 59.
The contact portion 59 is provided with a plurality of rectangular through holes 6. At least a part of the through-hole 6 is opened at a connection portion between the contact portion 59 and the lower plate 4. Specifically, the lower side of the through hole 6 having a rectangular shape is the upper surface of the lower plate 4. In other words, the through hole 6 is formed so that the water flowing on the upper surface of the lower plate 4 can flow to the opposite side while the contact portion 59 restricts the movement of the battery module 3.

  The lower plate 4 is formed with a drain hole 7 for discharging water on the lower plate 4 downward. The drain hole 7 is formed at a position different from the arrangement space S. That is, it is formed outside the region where the battery module 3 is disposed. The drain holes 7 are provided at both ends in the width direction of the lower plate 4 and at intermediate positions between the battery modules 3 adjacent in the longitudinal direction.

As shown in FIG. 7, the drain hole 7 is formed by forming two cuts in the lower plate 4 and then bending upward to form a bent portion 61. That is, the drain hole 7 is between the two cuts.
The drain hole 7 may be, for example, a rectangular hole formed in the lower plate 4 as long as at least a part of the drain hole 7 opens on the side of the lower plate 4.

The lower plate 4 is provided with a guide plate 8 for guiding moisture on the lower plate 4 to the drain hole 7. The guide plate 8 is a long plate-like member, and is disposed so that its main surface is orthogonal to the lower plate 4 and its longitudinal direction is along the short direction of the lower plate structure 2. The lower end of the guide plate 8 is joined to the upper surface of the lower plate 4 so that moisture flowing from one side in the longitudinal direction of the lower plate structure 2 does not leak to the other side of the guide plate 8. Yes.
Further, both ends in the longitudinal direction of the guide plate 8 are joined to bent portions 61 provided at both ends in the width direction of the lower plate 4.

Next, the battery module 3 will be described.
FIG. 8 shows the battery module 3 of this embodiment. As shown in FIG. 8, the battery module 3 includes an assembled battery 11 in which a plurality of unit cells 10 are arranged in a line in the thickness direction. The unit cell 10 is formed in a substantially rectangular parallelepiped shape having an electrode (not shown) on the top. The electrodes of each unit cell 10 are connected in series or in parallel by a tie bar (not shown) or the like. The assembled battery 11 includes a flat insulating member (insulating plate) 12 between adjacent unit cells 10. These insulating members mainly electrically insulate the opposing wall surfaces of the case C of each unit cell 10.

  The battery module 3 includes a casing 13 that houses the assembled battery 11. The casing 13 has side plates 16 that cover the end surfaces of the assembled battery 11 at both ends in the arrangement direction. These side plates 16 have flange portions 17 bent inward in the arrangement direction at their lower edges, and these flange portions 17 are arranged so as to wrap around the bottom surface 34 side of the assembled battery 11. Further, the side frame 14 is fixed to the side plate 16, and an inner plate 19 is disposed on the inner side in the arrangement direction of the side plates 16. These inner plates 19 are provided with bent portions 18 that are bent so that the outer edges in the width direction wrap around the side surfaces in the width direction of the assembled battery 11. Note that the direction intersecting the arrangement direction of the unit cells 10 and the extending direction of the support plate 30 to be described later are simply referred to as the width direction.

  The casing 13 further has an upper cover 20 that covers the upper part of the assembled battery 11. The upper cover 20 is for preventing water, dust and the like from adhering to each electrode and tie bar of the unit cell 10, and the upper inclined surface 21 formed on the upper cover 20 is electrically An access hole 22 for inserting a wiring for connection is formed. The casing 13 includes a support plate 30 that supports the assembled battery 11 from below. The support plate 30 includes support plate portions 30 a on both sides in the arrangement direction, and the support plate portions 30 a are supported by the flange portions 17 of the side plates 16.

  As shown in FIG. 9, the support plate 30 rises upward from both sides of the main plate portion 31 that supports the bottom surface 34 of the assembled battery 11 from below and the width direction orthogonal to the arrangement direction of the main plate portion 31. The side wall part 32 (regulation board) formed is provided. The side wall part 32 mainly restricts the assembled battery 11 from being displaced in the width direction. Thereby, the side surface 10a (refer FIG. 8) of the cell 10 is arrange | positioned on the same plane.

  As shown in FIGS. 9 and 10, the main plate portion 31 is provided with a plurality of discharge portions 33 for discharging a liquid such as water existing on the support plate 30 by its own weight. These discharge parts 33 are formed side by side in the arrangement direction. The discharge part 33 descends toward the both sides in the arrangement direction from the first support part 35 and the support part 36 including the first support part 35 that linearly contacts the bottom face 34 of the unit cell 10 in the center of the arrangement direction. The array-side inclined surface 37 formed as described above and the width-side inclined surface 38 that is connected to the lower edge of the array-side inclined surface 37 and inclines so as to descend outward in the width direction.

Further, between the first support portions 35 adjacent in the arrangement direction, a groove portion 40 extending in the width direction is formed at a position below the facing surface 39 (see FIG. 12) of each adjacent unit cell 10. Yes. These groove portions 40 are formed so as to be recessed in a direction away from the bottom surface 34 of the unit cell 10, and the groove bottom surface 41 is formed so as to be inclined downward in the width direction.
In addition, the width of the groove portion 40 is formed with a substantially constant width that is sufficiently larger than the gap between the cases C that form the outline of each unit cell 10. And the arrangement | sequence side inclined surface 37 mentioned above inclines so that it may space apart from the bottom face 34 of the cell 10 toward the groove part 40 from the 1st support part 35. As shown in FIG.
The first inclined surface is a surface inclined toward the direction of discharging water, and is the width-side inclined surface 37 and the groove bottom surface 41. Hereinafter, the case where both the width-side inclined surface 37 and the groove bottom surface 41 are inclined will be described as an example. However, the present invention is not limited to this. For example, the case where the width-side inclined surface 37 is inclined toward the groove portion 40 or The groove bottom surface 41 may be kept horizontal without being inclined. In addition, the arrangement-side inclined surface 38 is not limited to the case where the arrangement-side inclined surface 38 is formed so as to descend from the first support portion 35 toward both sides in the arrangement direction. For example, the arrangement-side inclined surface 38 is omitted together with the width-side inclined surface 37. May be.

  The support portion 36 includes a second support portion 42 that linearly contacts the bottom surface 34 of the unit cell 10 at the center in the width direction. The second support portion 42 is intermittently formed in the arrangement direction except for the portion where the groove portion 40 is formed, and the width-side inclined surface 38 is lowered from the second support portion 42 toward both sides in the width direction. It is inclined to. The groove bottom surface 41 is inclined so that the central portion in the width direction is the highest and goes down toward both sides in the width direction. The central portion in the width direction of the groove bottom surface 41 is disposed below in the vertical direction more than the central portion in the width direction of the width-side inclined surface 38. The width-side inclined surface 38 and the array-side inclined surface 37 are not limited to planes, and may be slightly concave or convex curved surfaces.

  The array-side inclined surface 37 is formed so that the width dimension in the array direction becomes thinner toward the center in the width direction. On the other hand, the array-side inclined surface 37 is formed so that the width dimension in the array direction becomes narrower toward the outer side in the width direction. Further, a ridge line formed by two array side inclined surfaces 37 adjacent in the array direction constitutes the first support portion 35, and a ridge line formed by two width side inclined surfaces 38 adjacent in the width direction is the first. The two support parts 42 are comprised.

  The side wall portion 32 has a plurality of vertical walls 43 that rise upward from the edge portion in the width direction of the array-side inclined surface 37 and the first support portion 35. The inner side surfaces 44 (see FIG. 10) in the width direction of the vertical walls 43 are connected to the array-side inclined surface 37 and the first support portion 35 via the concave curved surface 45. Further, an upper connection portion 46 is formed on the side wall portion 32 so as to cross over the upper portions of the adjacent vertical walls 43, and a lower side of the upper connection portion 46 and two opposite side portions of the vertical wall 43, A second through hole 47 penetrating the inner side and the outer side of the side wall portion 32 toward the outer side in the width direction is formed by the side portion of the main plate portion 31. In addition, although the example which connects the inner surface 44, the arrangement | sequence side inclined surface 37, and the 1st support part 35 with the concave curved surface 45 was demonstrated, it is not restricted to this.

  As shown in FIG. 10, the insulating members 12 disposed between the single cells 10 are disposed at approximately the center of the width-side inclined surface 38 in the array direction, more specifically, approximately at the center of the groove portion 40 in the array direction. ing. Further, as shown in FIG. 11, the insulating member 12 is inclined so that the groove bottom surface 41 is in close contact with the groove bottom surface 41, in other words, the entire edge on the groove bottom surface 41 side is in contact with the groove bottom surface 41. It has a shape corresponding to. That is, the lower edge of the insulating member 12 includes an inclined bottom surface 48 that is inclined downward from both sides in the width direction from the center portion in the width direction.

The battery module 3 is fixed by the support plate 30 being fastened to the lower plate 4 by a fastening member such as a bolt.
The battery module 3 is not limited to the module structure of the present embodiment as long as the water inside the battery module 3 can be discharged to the outside.

Next, the operation of the battery pack 1 will be described. In the description of this action, condensation is caused by cooling the assembled battery 11 with cooling air or the like, and condensed water (hereinafter referred to as water) generated by this condensation falls on the support plate 30 and is discharged. An example will be described.
First, water adhering to the surface of the unit cell 10 moves along the side surface due to its own weight and moves to the bottom surface 34 side. Then, the liquid drops or flows down on the support plate 30 mainly from between the lower corner portion of the unit cell 10 and the portion that contacts the support portion 36 of the bottom surface 34.

At this time, the water dropped on the array side inclined surface 37 or flowing down through the first support portion 35 is lowered along the array side inclined surface 37 by its own weight as shown by an arrow in FIG. It moves toward the side and moves on the width side inclined surface 38.
On the other hand, the water dropped on the width-side inclined surface 38 or flowing down through the second support portion 42 flows downward along the width-side inclined surface 38 toward the outside in the width direction due to its own weight. Most of the side inclined surface 38 flows into the groove 40 because the side inclined surface 38 becomes thinner toward the outer side in the width direction.

  The water directly dropped inside the groove 40, the water flowing down through the insulating member 12, and the water flowing from the width-side inclined surface 38 are widthwise along the inclination of the groove bottom surface 41 of the groove 40 due to its own weight. It flows toward the outer side and the lower side, and is discharged from the second through hole 47 of the side wall portion 32 to the outer side in the width direction of the support plate 30. The movement of the water in the groove 40 in the arrangement direction is restricted by the insulating member 12, so that the water generated from the two adjacent unit cells 10 is not mixed with each other.

  Next, the water discharged from the second through hole 47 is guided to the drain hole 7 by the side plate 55 (or the cover 50) as shown in FIG. Here, the water discharged from the second through hole 47 of the side wall portion 32 with which the pressing plate 5 is in contact is discharged through the through hole 6 of the pressing plate 5.

  Further, the water on the lower plate 4 including the water discharged from the through hole 6 is also guided to the drain hole 7 by the guide plate 8. That is, the water on the lower plate 4 is guided to the drain hole 7 by the side plate 55 and the guide plate 8. The water discharged from the drain hole 7 once flows down into the channel steel 54 (see FIG. 4) and is discharged from the frame hole 56 to the outside of the battery pack 1.

  According to the above embodiment, the drain hole 7 is formed in the lower plate 4, so that liquid such as water caused by condensation can be discharged to the outside of the battery pack 1. Further, since the through hole 6 is formed in the pressing plate 5, the water discharged from the support plate 30 can be discharged from the through hole 6 while positioning the battery module 3. Thereby, the influence of the water in the battery pack 1 can be suppressed, and the structure of the battery pack 1 in which the unit cell 10 is difficult to corrode can be formed.

  Further, the lateral displacement of the unit cell 10 is regulated by the side wall 32, and the water in the battery module 3 can be discharged to the outside of the battery module 3 through the through hole 6 and the second through hole 47. it can.

  Further, the guide plate 8 guides the water on the lower plate 4 to the drain hole 7, so that the water on the lower plate 4 can be prevented from staying inside the battery pack 1.

  Furthermore, according to the battery module 3 of the above embodiment, it is possible to prevent water caused by condensation or the like from being discharged to the outside in the width direction by the support plate 30 and collecting water between adjacent unit cells 10. It is possible to prevent the occurrence of problems such as corrosion by suppressing the electrical connection between the cases of the adjacent unit cells 10.

Further, since water can be moved by its own weight along the inclination of the array side inclined surface 37 and the width side inclined surface 38, the water on the support plate 30 can be discharged with a simple configuration.
Furthermore, since the groove portion 40 is disposed between the support portions 36, the support portion 36 can support the bottom surface 34 of each unit cell 10, and water attached to each unit cell 10 flows downward. In such a case, the water can be caused to flow into the groove portion 40, so that even if a minute shaking or the like occurs, the water that has flowed into the groove portion 40 can be prevented from adhering to the cell 10 again.

Further, since the groove bottom surface 41 of the groove portion 40 is inclined, the water flowing into the groove portion 40 can be smoothly discharged from the support plate 30. Furthermore, since no vertical through-hole is formed in the support plate 30, it is possible to prevent water from entering from below.
In addition, since the width-side inclined surface 38 and the groove bottom surface 41 are inclined outward from the center in the width direction, the water that has dropped or flowed onto the width-side inclined surface 38 and the groove bottom surface 41 is the shortest distance. It becomes possible to discharge | emit to the width direction outer side of the support plate 30, and water can be discharged | emitted rapidly.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in the present embodiment, only one side in the width direction of the battery module 3 is positioned by the pressing plate 5, but both the width direction sides of the battery module 3 may be positioned by the pressing plate 5.
The guide plate is not necessarily provided, and the manufacturing cost of the battery pack may be reduced by omitting the guide plate.
Further, the support plate (bottom plate member) may be omitted.

DESCRIPTION OF SYMBOLS 1 Battery pack 2 Lower plate structure 3 Battery module 4 Lower plate 5 Holding plate 6 Through hole 7 Drain hole 8 Guide plate 10 Single cell 10a Side surface 30 Support plate (bottom plate member)
32 Side wall (regulatory plate)
47 Second through hole

Claims (5)

A battery module in which a plurality of unit cells are arranged, and side surfaces of the plurality of unit cells parallel to the arrangement direction are aligned on the same plane;
A lower plate on which a plurality of the battery modules are placed side by side;
A pressing plate that protrudes upward from the lower plate and contacts the side surface of the battery module along the plane from the outside,
A through hole formed in the holding plate and penetrating a region in contact with the side surface of the battery module;
A on the lower plate, have a, a drain hole which penetrates the lower plate is provided outside the region where the battery module is arranged,
A battery pack, wherein a part of the through hole reaches the lower plate .   A battery module in which a plurality of unit cells are arranged, and side surfaces of the plurality of unit cells parallel to the arrangement direction are aligned on the same plane;
  A lower plate on which a plurality of the battery modules are placed side by side;
  A pressing plate that protrudes upward from the lower plate and contacts the side surface of the battery module along the plane from the outside,
  A through hole formed in the holding plate and penetrating a region in contact with the side surface of the battery module;
  A drain hole provided on the lower plate and outside the region where the battery module is disposed and penetrating the lower plate;
  In the battery module, the plurality of single cells are arranged along a bottom plate member,
  A regulating plate protruding from the bottom plate member at a position included in the plane;
  A second through hole provided in the restriction plate,
  The pressing plate is in contact with the regulating plate,
  The battery pack, wherein the through hole is provided in a region in contact with the regulation plate.   2. The battery pack according to claim 1, wherein the battery module includes a plurality of single cells arranged along a bottom plate member. A regulating plate protruding from the bottom plate member at a position included in the plane;
A second through hole provided in the restriction plate,
The pressing plate is in contact with the regulating plate,
The battery pack according to claim 3 , wherein the through hole is provided in a region in contact with the restriction plate. A guide plate that continuously protrudes upward from the lower plate and partitions between one battery module arranged on the lower plate and another adjacent battery module;
The battery pack according to any one of claims 1 to 4 , wherein the guide plate guides water from the battery module to the drain hole.

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