JP6575166B2 - Battery pack - Google Patents

Description

  The present invention relates to a vehicle battery pack.

  Conventionally, a hybrid vehicle, an electric vehicle, and the like provided with a battery pack are known. A battery pack used for an automobile is required to have a large energy capacity and be capable of rapid charge / discharge. Therefore, a lithium ion battery or the like is adopted. As such a battery pack, there are a type in which an electrode is wound and a type in which an electrode is laminated. In order to constitute a secondary battery excellent in rapid charge / discharge, a laminated battery pack is used.

  In such a stacked type battery pack, in order to improve assembly workability, a stack member is disposed between a plurality of battery cells, and the stack member is between electrically connected external terminals that are electrically disconnected. A first insulating portion that prevents contact; and a second insulating portion that is positioned between and supports adjacent external terminals that are electrically connected to each other, and a fixed recess is formed in the second insulating portion. At the same time, an L-type connection terminal made of conductive metal is welded to the external terminal, and the L-type connection terminal is arranged by overlapping a part of each other, and the overlapped portion is screwed to the nut plate fixed to the fixing recess. A stopped battery pack has been proposed (see, for example, “Patent Document 1”).

Japanese Patent No. 5398273

The technique disclosed in “Patent Document 1” has a problem that when a large impact is applied to a vehicle such as a collision, the stacked battery cells are displaced by the impact and the battery pack is destroyed. As a method for preventing this, a configuration is considered in which through holes are provided at the four corners of each stacked battery cell and the four corners of each battery cell are supported by four long bolts. There is a problem that it breaks when it acts.
An object of the present invention is to solve the above-described problems and to provide a battery pack capable of reducing impacts on stacked battery cells when a large impact is applied to a vehicle such as a collision.

The invention according to claim 1 has a plurality of flat-stacked batteries, at least one battery has a convex portion on one surface side, and another battery adjacent to the battery is on the one surface. the protrusions have a engageable engagement portion on the other surface side which faces the convex portion has a flange, said engaging portion and said to have a contact portion for receiving said flange To do.

According to a second aspect of the present invention, in the battery pack according to the first aspect, the convex portion and the engaging portion are spaced from each other when no external force is applied.

According to a third aspect of the present invention, in the battery pack according to the first or second aspect , the battery pack further includes a movement restricting member that restricts the plurality of batteries from moving in the vertical direction .

According to a fourth aspect of the present invention, in the battery pack according to the third aspect , the movement restricting member is a bolt, a through hole is formed in each of the plurality of batteries, and the bolt is inserted into the through hole. and said that you are.
According to a fifth aspect of the present invention, in the battery pack according to the fourth aspect, the distance between the convex portion and the engaging portion is set smaller than the distance between the bolt and the through hole. And

  According to the present invention, the impact at the time of movement of each battery can be received by each convex portion, and even if each convex portion is deformed or damaged at the time of collision, the weakened impact can be received by each bolt, By dispersing the impact force, the impact on the battery can be reduced.

It is a schematic sectional drawing explaining the problem of the conventional battery pack. It is a schematic perspective view explaining the problem of the conventional battery pack. It is the schematic of the battery pack to which one Embodiment of this invention is applied. It is the schematic explaining the battery cell to which one Embodiment of this invention is applied. It is the schematic explaining the state of the convex part and hole in one Embodiment of this invention. It is a schematic perspective view explaining the time of the external force effect | action of the battery pack to which one Embodiment of this invention is applied.

  FIG. 1A shows a battery pack of a vehicle that has been conventionally used. In the figure, the battery pack 1 is disposed at a part between the front wheel and the rear wheel at the bottom of the vehicle body. The battery pack 1 is composed of a cover 2 and a tray 3 made of iron plate on the outside, and inside the tray 3 are a plurality of (four in this embodiment) battery modules 5 as secondary batteries that form secondary batteries. The fixing member 4 is stacked and accommodated. The battery module 5 is configured by laminating a plurality of plate-shaped battery cells (not shown). Through holes are formed in the four corners of the battery module 5, and as shown in FIG. 2A, four bolts 6 are arranged through the through holes. Each bolt 6 is screwed into a screw hole (not shown) provided in the fixing member 4 and fastens each battery module 5 so as not to move in the vertical direction. By this fastening, the movement of each battery module 5 in the left-right direction is also suppressed.

  Here, the problems of the prior art will be described. In the above-described configuration, when a large impact such as a collision from the right in FIG. 1A acts on the battery pack 1 as shown by an arrow, as shown in FIGS. 1B and 2B. In addition, each battery module 5 may be displaced laterally, and the battery module 5 may come into contact with the cover 2. If the lateral movement of each battery module 5 is merely suppressed, the clearance between each bolt 6 and the through-hole through which the bolt 6 passes may be reduced. However, in the conventional battery module structure, since the impact is received only at four places of the bolt 6, the impact on the battery module or the battery cell is increased. The configuration of the present invention that prevents the occurrence of this problem will be described below.

  FIG. 3 shows a battery pack to which an embodiment of the present invention is applied. In the figure, the battery pack 11 includes a cover 12 made of an iron plate and a tray 13, and a plurality (four in this embodiment) of battery modules 15 constituting secondary batteries serve as a fixed base inside the tray 13. The fixing member 14 is stacked and accommodated. The battery module 15 is configured by laminating a plurality of plate-shaped battery cells 17. Through holes 18 are formed at the four corners of the battery module 15, and four bolts 16 as movement restriction members are inserted into the through holes 18. Each bolt 16 is screwed into a screw hole (not shown) provided in the fixing member 14 and fastens each battery module 15 so as not to move in the vertical direction. By this fastening, the movement of each battery module 15 in the left-right direction is also suppressed.

  As shown in FIGS. 3 and 4, the battery modules 15 other than the lowermost stage (in the present embodiment, the first stage, the second stage, and the third stage from the top) are arranged on the bottom surface 15 a of the sheet metal case constituting the outside thereof. It has the convex part 20 of the location. Each convex portion 20 has a stepped cylindrical shape made of metal, and the small diameter side end portion of the bottom surface 15a of the sheet metal case of the battery module 15 similarly made of metal by a method such as welding or screwing. Is firmly fixed. A flange 20 a is formed by the large-diameter end of each convex portion 20.

  The battery modules 15 other than the uppermost stage (in the present embodiment, the second stage, the third stage, and the fourth stage from the top) have four holes as engaging portions that can engage the convex portions 20 on the upper surface side. Part 21. Each hole 21 is formed in the upper surface 15b of the sheet metal case of the battery module 15, and the diameter thereof is formed to be slightly larger than the diameter of the flange 20a. Moreover, when each convex part 20 engages with each hole 21, the space | interval S (refer FIG.5 (a)) of the small diameter part of each convex part 20 and the upper surface 15b which is an edge of each hole 21 is as follows. The clearance between the bolt 16 and the through hole 18 is configured to be smaller.

  In the configuration described above, when an external force similar to that of the battery pack 1 acts on the battery pack 11 from the right side in FIG. 3, each battery module 15 is shifted laterally as shown in FIG. At this time, as shown in FIG. 5B, each projection 20 collides with the upper surface 15b which is the edge of each hole 21, but each projection 20 is firmly fixed to the bottom surface 15a of the sheet metal case. Therefore, the damage of each convex part 20 does not occur. Since the interval S is set to be smaller than the clearance between the bolt 16 and the through-hole 18, each bump 20 collides with the edge of each hole 21 first at the time of collision, and in some cases, each hole The edge of the portion 21 is deformed, and then the bolts 16 come into contact with the through holes 18 to disperse the impact. Thereby, the impact at the time of movement of each battery module 15 can be received by each projection 20, and even if each projection 20 is damaged at the time of a collision, the weakened impact can be received by each bolt 16. Dispersion of the impact force can alleviate the damage of each bolt 16 and the impact of each battery module 15. Further, by making the distance S equal to the clearance between the bolts 16 and the through holes 18, it is possible to disperse and absorb external forces such as impacts between the bolts 16 and the projections 20, and damage the bolts 16. And damage to each battery module 15 can be prevented.

  In the above embodiment, the battery modules 15 are not moved up and down by fixing the four corners of the battery modules 15 with the bolts 16. However, the bolts 16 may not be used. In this case, when each battery module 15 moves up and down, the up and down movement of each battery module 15 is suppressed by the upper surface of each flange 20a coming into contact with the contact portion on the back side of the upper surface 15b. Moreover, when it is set as the structure which uses each volt | bolt 16, it does not necessarily need to form the flange 20a in each convex part 20. As shown in FIG.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the specific embodiments described above, and is described in the claims unless specifically limited by the above description. Various modifications and changes can be made within the scope of the present invention. For example, in the present embodiment, an example in which a battery module is used as a battery has been described. However, the battery is not limited thereto, and may be a battery cell, for example. The effects described in the embodiments of the present invention are only the most preferable effects resulting from the present invention, and the effects of the present invention are not limited to those described in the embodiments of the present invention. .

DESCRIPTION OF SYMBOLS 11 ... Battery pack, 15 ... Battery (battery module), 16 ... Movement control member (bolt), 20 ... Convex part, 20a ... Flange, 21 ... Engagement part (hole) Part)

Claims (5)

The battery has a plurality of flatly stacked batteries, and at least one battery has a convex portion on one surface side, and the other battery adjacent to the battery is on the other surface side facing the one surface. protrusions have a engageable engagement portion,
The convex portion has a flange, said engaging portion is a battery pack to have a contact portion for receiving the flange. The battery pack according to claim 1, wherein
The battery pack, wherein the convex portion and the engaging portion are spaced apart from each other when no external force is applied. The battery pack according to claim 1 or 2 ,
A battery pack comprising a movement restricting member for restricting movement of the plurality of batteries in the vertical direction . The battery pack according to claim 3 , wherein
The movement restricting member is a bolt, a through hole is formed in each of the plurality of batteries, and the bolt is inserted into the through hole . The battery pack according to claim 4,
The battery pack according to claim 1, wherein an interval between the convex portion and the engaging portion is set smaller than an interval between the bolt and the through hole.

Images