JP7111675B2 - Battery pack and battery module removal method - Google Patents

Description

The present invention relates to battery packs.

In order to uniformly cool each cell of a battery pack including a battery module having a plurality of cells, a heat transfer sheet having adhesiveness and elasticity is brought into close contact with the cooling surface of the battery module and a cooling member such as a cooling plate, The heat of the battery module is efficiently transferred to the cooling member to enhance the cooling performance (see, for example, Patent Document 1, etc.).

JP 2014-157763 A

However, in general, the heat transfer sheet has high adhesiveness and sticks firmly to the battery module during use. Therefore, when the battery module needs to be replaced, it is difficult to peel off the battery module from the heat transfer sheet.

In order to prevent the heat transfer sheet from sticking to the battery module, a method of attaching a film to the heat transfer sheet is known. However, when a film is attached to the heat transfer sheet, there is a problem that the heat transfer efficiency deteriorates and the cooling performance deteriorates.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a battery pack that does not require a film to be attached to a heat transfer member, and in which a battery module can be easily peeled off from the heat transfer member.

(1) A battery pack according to the present invention is a battery pack (for example, a battery pack 1 described later) in which a battery module (for example, a battery module 2 described later) is accommodated in a case (for example, a case 3 described later). , the battery pack includes a cooling member for cooling the battery module (for example, a member configured by a bottom portion 31, a cooling channel groove 311, and a bottom outer lid 312, which will be described later), and a space between the battery module and the cooling member. and a heat transfer member having adhesiveness (for example, a heat transfer sheet 4 to be described later) disposed in the case, the battery module and the heat transfer member are in direct contact, and the battery module is attached to the case. A female thread (for example, a female thread 51 to be described later) into which a male threaded member (for example, a male threaded member 100 to be described later) can be screwed is provided at a location accessible from the outside.

According to the above (1), even if the battery module is in close contact with the cooling member by the adhesive heat transfer member, the battery module can be easily removed from the heat transfer member by screwing the male screw member such as the bolt into the female screw. can be torn off. Therefore, it is possible to provide a battery pack in which it is not necessary to attach a film to the heat transfer member, and the battery module can be easily peeled off from the heat transfer member.

(2) In the battery pack described in (1), the battery module has a plate-like member (for example, a lower plate 23 to be described later) that is in direct contact with the heat transfer member, and the female thread is provided in the plate-like member. may be provided in

According to the above (2), female threads can be easily formed in the battery module by using the plate member.

(3) In the battery pack described in (2), the cooling member is made of metal, and ribs (for example, ribs 313 to be described later) projecting in the direction of the female thread are provided in portions overlapping with the female thread. good too.

According to (3) above, since the rib of the metal cooling member is arranged at the portion where the male screw member abuts, the rigidity of the cooling member is increased, and even if the heat transfer member is firmly attached to the plate-like member, , can be easily peeled off by abutting the male threaded member against the rib.

(4) In the battery pack described in (3), the cooling member may be die-cast.

According to (4) above, the cooling member having ribs can be easily processed.

(5) In the battery pack according to any one of (2) to (4), the plate-like member includes a protrusion (for example, a protrusion 231 to be described later) that protrudes from the battery module in the longitudinal direction of the battery module. ), and the female thread may be provided on the protrusion.

According to (5) above, the female screw is provided on the projecting portion projecting in the longitudinal direction of the battery module, so that the battery module can be easily peeled off from the heat transfer member by the principle of leverage.

(6) In the battery pack described in (5), the plate-shaped member has two fixing portions (for example, fixing bolt insertion holes 232 described later) with respect to the cooling member in the projecting portion, and the female screw is , in the protrusion, may be arranged between the two fixing parts.

According to (6) above, there is no need to unnecessarily extend the plate-like member outside the two fixing portions in order to form the internal thread, so space efficiency is good.

(7) In the battery pack according to any one of (2) to (4), the battery module includes a plurality of stacked cells (for example, cells 21 to be described later) and a stacking direction of the plurality of cells (for example, and end plates (for example, end plates 22 described later) arranged at both ends in the direction of X1-X2 described later), and at least one of the end plates is arranged in a direction facing the plate-like member ( For example, a through-hole (for example, a through-hole 221 to be described later) may be provided penetrating in the Z1-Z2 direction (to be described later), and the female thread may be arranged to overlap with the through-hole.

According to (7) above, it is no longer necessary to project the plate-like member from the battery module in order to provide the female screw, and the battery module can be made compact.

(8) In the battery pack according to any one of (1) to (7), the cooling member may constitute at least part of the case.

According to (8) above, the configuration of the battery pack can be simplified.

According to the present invention, it is possible to provide a battery pack in which it is not necessary to attach a film to the heat transfer member, and the battery module can be easily peeled off from the heat transfer member.

It is a perspective view which shows the principal part of the battery pack which concerns on one Embodiment with a cross section. 1 is an exploded perspective view showing a cross section of a main part of a battery pack according to an embodiment; FIG. It is the perspective view which looked at the battery module which concerns on one Embodiment from the bottom face side. FIG. 2 is a vertical cross-sectional view taken along line AA in FIG. 1; FIG. 5 is a diagram showing how the battery module is peeled off from the heat transfer member; FIG. 10 is a perspective view showing a main part of a battery module according to another embodiment; FIG. 10 is a perspective view of a main part of a battery module according to another embodiment, viewed from the bottom side;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.
A battery pack 1 of the present embodiment is a battery pack mounted in a vehicle such as an electric vehicle or a hybrid vehicle. As shown in FIGS. , and a heat transfer sheet 4 .

The battery module 2 includes a plurality of stacked rectangular parallelepiped cells 21, end plates 22 arranged at both ends of the cells 21 in the stacking direction (the Y1-Y2 direction in this embodiment), and the bottom surfaces of the cells 21. It has a lower plate 23 arranged on the side and a pair of bind bars 24 , 24 provided over the end plates 22 , 22 . A pair of bind bars 24 , 24 are fixed to the end plates 22 , 22 by a plurality of bolts 241 and bind the entire plurality of stacked cells 21 and lower plates 23 .

The lower plate 23 is a single plate-like member made of a metal material with good heat conductivity such as copper or aluminum, and has a size that allows direct contact with the bottom surfaces of all the cells 21 that are stacked in plurality. The lower plate 23 of this embodiment has a substantially rectangular shape elongated along the stacking direction of the cells 21, and protrudes from both ends in the longitudinal direction of the battery module 2 (Y1-Y2 direction in this embodiment). It has protrusions 231, 231 that

Protrusions 231 , 231 constitute fixing parts for fixing battery module 2 to case 3 . Each of the projecting portions 231 , 231 is provided with two fixing bolt insertion holes 232 which are fixing portions to the case 3 at two positions corresponding to the four corners of the lower plate 23 . The two fixing bolt insertion holes 232, 232 of the projections 231, 231 are separated in the width direction of the lower plate 23 (X1-X2 direction). The lower plate 23 , including these protruding portions 231 , 231 , has substantially the same width as the cell 21 (X1-X2 direction in this embodiment) and extends in the longitudinal direction of the battery module 2 .

The case 3 is a bottomed container having a bottom portion 31 and side wall portions 32 rising from the periphery of the bottom portion 31 . A lid member (not shown) made of metal or resin is provided on the upper portion of the case 3 . The battery modules 2 housed in the case 3 are mounted on the upper surface 31 a of the bottom portion 31 of the case 3 . Four fixing bolts 33 for fixing the battery module 2 to the bottom portion 31 are projected from the upper surface 31 a of the bottom portion 31 at positions corresponding to the four fixing bolt insertion holes 232 of the lower plate 23 . The battery modules 2 are fixed to the case 3 by nuts (not shown) that are screwed onto the fixing bolts 33 after the fixing bolts 33 are inserted through the fixing bolt insertion holes 232 . In the battery pack 1 shown in FIGS. 1 and 2, only one battery module 2 is fixed to the bottom portion 31 of the case 3. Similarly, to the bottom portion 31 of the case 3, X1 A plurality of battery modules 2 are fixed in the Y direction and the Y1 direction.

The case 3 of this embodiment also functions as a cooling member that cools the battery module 2 . That is, in the bottom portion 31 of the case 3, on the side of the lower surface 31b corresponding to the area where the battery module 2 is mounted, there are a cooling channel groove 311 recessed toward the battery module 2 and a cooling channel groove 311 of the cooling channel groove 311. A bottom outer lid 312 is provided which watertightly encloses the .

Case 3 cools battery module 2 via bottom portion 31 by circulating cooling water in cooling channel groove 311 between bottom surface 31 b side of bottom portion 31 and bottom outer cover 312 . Therefore, in the battery pack 1, the cooling member for cooling the battery modules 2 is composed of at least the bottom portion 31 of the case 3, the bottom outer cover 312, and the cooling channel grooves 311 formed therebetween. Such a cooling member constitutes at least part of the case 3 that houses the battery module 2 . Therefore, it becomes unnecessary to provide the case 3 with a cooling member separate from the case 3, and the configuration of the battery pack 1 can be simplified.

The case 3, which also functions as a cooling member, is made of a metal material with good heat conductivity, such as copper or aluminum, at least at the bottom 31 where the battery module 2 is mounted. As a result, heat exchange between the cooling water flowing in the cooling channel grooves 311 and the battery modules 2 is performed well through the bottoms 31, and the battery modules 2 can be efficiently cooled.

A plurality of ribs 313 are provided on the upper surface 31 a of the bottom portion 31 so as to correspond to the areas where the cooling channel grooves 311 are formed. The ribs 313 are formed in a lattice shape extending in the X1-X2 direction and the Y1-Y2 direction which are orthogonal to each other. By forming ribs 313 on bottom portion 31 , the cross-sectional rigidity of bottom portion 31 is improved, and damage to bottom portion 31 when battery module 2 is fixed is reduced. When the bottom portion 31 is die-cast, the ribs 313 facilitate the flow of molten metal during casting, so the cooling member having the ribs 313 can be easily processed.

The heat transfer sheet 4 is arranged on the upper surface 31a of the bottom portion 31 corresponding to the area where the battery modules 2 are placed. The heat transfer sheet 4 is a heat transfer member made of a resin sheet having good heat transfer properties and adhesiveness. The heat transfer sheet 4 is divided into a plurality of pieces in the X1-X2 direction and the Y1-Y2 direction for each battery module 2 . With the lower plate 23 facing the bottom portion 31 , the battery module 2 inserts the fixing bolts 33 protruding from the bottom portion 31 of the case 3 into the respective fixing bolt insertion holes 232 . It is fixed to the upper surface 31a of the bottom portion 31 through the hole. Therefore, the lower plate 23 of the battery module 2 is in direct contact with the multiple heat transfer sheets 4 .

3 and 4, the lower plate 23 extends over the entire length of the lower plate 23 along the stacking direction of the cells 21 at the central portion of the lower surface that directly contacts the heat transfer sheet 4. A recess 233 is provided. Thereby, a space capable of accommodating the heat transfer sheet 4 is formed between the lower plate 23 and the bottom portion 31 . When the battery module 2 is fixed to the bottom portion 31 , the heat transfer sheet 4 is accommodated in the recess 233 . It can be brought into direct contact with the upper surface 31a of the bottom portion 31 on which the sheet 4 is not arranged. Therefore, the battery module 2 is stably fixed to the bottom portion 31 .

In order to easily separate the battery modules 2 from the heat transfer sheet 4 when removing the battery modules 2 accommodated in the case 3 from the bottom 31 of the case 3 in this way, the battery modules 2 are equipped with a Aside from the fixing holes (fixing bolt insertion holes 232 through which the fixing bolts 33 are inserted), a threaded hole 5 having a female thread 51 for screwing and inserting a removal member is provided. At least one screw hole 5 is provided at a location accessible from the outside of the case 3 housing the battery module 2 .

As shown in FIGS. 1 to 3, the screw holes 5 are provided in the lower plate 23 in this embodiment. By using lower plate 23 , screw hole 5 having female screw 51 can be easily formed in battery module 2 . Specifically, the screw holes 5 are provided in the protrusions 231 of the lower plate 23 that are easily accessible from the outside of the case 3 . The screw holes 5 pass through the lower plate 23 . A female thread 51 is provided on the inner peripheral surface of the screw hole 5 as shown in FIG.

Next, a method of removing the battery module 2 from the bottom portion 31 of the case 3 using the screw hole 5 in the battery pack 1 will be described with reference to FIG.
When removing the battery module 2 from the bottom portion 31 of the case 3 , a male screw member 100 such as a bolt is inserted into the screw hole 5 . A male screw 102 that can be screwed into the female screw 51 is provided on the outer circumference of the shaft portion 101 of the male screw member 100 . When removing the battery module 2, nuts (not shown) screwed onto the fixing bolts 33 are removed.

When the male threaded member 100 inserted into the threaded hole 5 is rotated forward using a tool (not shown), the male threaded member 100 is pushed into the threaded hole 5 toward the bottom 31 of the case 3 by screwing the male thread 102 and the female thread 51 together. The male screw member 100 gradually enters the inside, and the tip 103 of the male screw member 100 hits the bottom 31 before long. When the male screw member 100 is further rotated forward from this state, the lower plate 23 is gradually displaced upward along the shaft portion 101 of the male screw member 100, and the heat transfer sheet 4 is gradually peeled off along with this. Therefore, according to the battery pack 1, even if the battery module 2 is in close contact with the bottom portion 31 by the adhesive heat transfer sheet 4, there is no need to attach a film to the heat transfer sheet 4. The sheet 4 can be easily peeled off.

As shown in FIG. 4 , the screw hole 5 is arranged so as to overlap a rib 313 provided on the upper surface 31 a of the bottom portion 31 of the case 3 and opens directly above the rib 313 . Therefore, the distal end portion 103 of the male screw member 100 abuts against the metallic rib 313 . Since the rigidity of the bottom portion 31 is increased by the ribs 313, deformation or the like is not caused even if the tip portion 103 of the male screw member 100 bumps against it. Therefore, even if the heat transfer sheet 4 is firmly attached to the lower plate 23 , it can be easily peeled off by striking the male screw member 100 against the rib 313 .

Since the screw hole 5 is provided in the projecting portion 231 projecting in the longitudinal direction of the battery module 2 , when the male threaded member 100 is rotated, the battery module 2 gradually tilts in the longitudinal direction. Therefore, the battery module 2 can be easily peeled off from the heat transfer sheet 4 by the principle of leverage. In particular, the screw holes 5 of the present embodiment are arranged in one direction from the central portion of the lower plate 23 in the width direction (X1-X2 direction). According to this, the battery module 2 can be tilted diagonally in the longitudinal direction and the width direction by the rotation of the male screw member 100, so that the heat transfer sheet 4 can be further easily peeled off.

The screw hole 5 is arranged between two fixing bolt insertion holes 232 , 232 which are provided in the projecting portion 231 of the lower plate 23 so as to be spaced apart in the width direction. Therefore, it is not necessary to unnecessarily widen the lower plate 23 to the outside (X1 direction or X2 direction) of the two fixing bolt insertion holes 232 , 232 in order to form the screw holes 5 . As a result, the plurality of battery modules 2 can be arranged as close as possible within the case 3, so space efficiency can be improved.

6 and 7 show another embodiment of the battery module 2. FIG. In this battery module 2, at least one end plate 22 is provided with a through hole 221 penetrating in a direction facing the lower plate 23 (Z1-X2 direction). The threaded hole 5 having the internal thread 51 is not provided in the projecting portion 231 of the lower plate 23 but is provided in a portion overlapping the through hole 221 provided in the end plate 22 . The screw hole 5 faces the inside of the through hole 221 . The through-hole 221 surrounds the entire screw hole 5 and has a size that allows the male screw member 100 (see FIG. 5) to be inserted through the through-hole 221 and is rotatable. Therefore, the screw holes 5 in this battery module 2 are accessible from the outside through the through holes 221 of the end plates 22 .

This eliminates the need for the lower plate 23 to protrude from the battery module 2 in order to provide the female screw 51, so that the protruding portion 231 of the lower plate 23 can be of a minimum size that allows the fixing bolt insertion holes 232, 232 to be provided. . For example, the projecting portion 231 of the lower plate 23 shown in FIGS. 6 and 7 is provided only at the portions where the fixing bolt insertion holes 232, 232 are provided. Therefore, the weight and size of the battery module 2 can be reduced.

Reference Signs List 1 battery pack 2 battery module 21 cell 22 end plate 221 through hole 23 lower plate (plate-like member)
231 protruding portion 232 fixing bolt insertion hole (fixing portion)
3 case 31 bottom (cooling member)
311 cooling channel groove (cooling member)
312 bottom outer cover (cooling member)
313 rib 4 heat transfer sheet (heat transfer member)
51 internal thread 100 external thread member

Claims (9)

A battery pack containing a battery module in a case,
a cooling member provided at the bottom of the case for cooling the battery module;
a heat transfer member having adhesiveness disposed between the battery module and the cooling member;
The battery module has a plate-like member that directly contacts the heat transfer member,
The battery module is a battery pack, wherein a screw hole having a female screw into which a male screw member can be screwed is provided in a portion of the plate-like member that is accessible from the outside of the case and faces the bottom of the case . 2. The battery pack according to claim 1 , wherein said cooling member is made of metal and provided with a rib projecting in a direction of said screw hole in a portion overlapping said screw hole. 3. The battery pack according to claim 2 , wherein said cooling member is die-cast. the plate member has a protruding portion protruding from the battery module in the longitudinal direction of the battery module;
The battery pack according to any one of claims 1 to 3 , wherein said screw hole is provided in said projecting portion. the plate-shaped member has two fixing portions for the cooling member on the projecting portion;
5. The battery pack according to claim 4 , wherein the screw hole is arranged between the two fixing parts in the protrusion. The battery module has a plurality of stacked cells and end plates arranged at both ends of the plurality of cells in the stacking direction,
at least one of the end plates has a through hole penetrating in a direction facing the plate member;
The battery pack according to any one of claims 1 to 3 , wherein said screw hole is arranged to overlap said through hole. The battery pack according to any one of claims 1 to 6 , wherein said cooling member constitutes at least part of said case. The battery pack according to any one of claims 1 to 7, wherein said plate-like member has said male screw member screwed into said screw hole. A battery module is housed in a case having a cooling member at the bottom, and a plate member of the battery module is in direct contact with a heat transfer member having adhesiveness disposed between the battery module and the cooling member. A method for removing the battery module in a battery pack, comprising:
The plate-shaped member has a threaded hole with a female screw at a location accessible from the outside of the case and facing the bottom of the case,
When the battery module that is not fixed to the case is removed, the shaft portion of the male screw member is screwed into the screw hole, and the tip portion of the shaft portion is brought into contact with the bottom portion of the case by rotating the male screw member. A method for removing a battery module, wherein the plate-shaped member is abutted and displaced upward along the shaft with respect to the bottom of the case to separate the battery module from the heat transfer member.

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