WO2016151972A1

WO2016151972A1 - Battery module

Info

Publication number: WO2016151972A1
Application number: PCT/JP2015/086516
Authority: WO
Inventors: 浩生植田; 英史大石; 加藤　崇行
Original assignee: 株式会社豊田自動織機
Priority date: 2015-03-24
Filing date: 2015-12-28
Publication date: 2016-09-29
Also published as: JP2016181408A; JP6277987B2

Abstract

The battery module 1 comprises: an array body 2 wherein battery cells 11 are arrayed through a temperature control member 33 therebetween; and a pair of restraining members 3, 3 disposed in such a way as to sandwich the array body 2 and applying a restraining load in the arraying direction of the battery cells 11. The temperature control member 33 comprises a base 34, and a plurality of ribs 35 protruding on one side of the base 34 and in contact with an adjacent battery cell 11. An elastic body 4 is disposed between one of the restraining members 3 and an extremity side battery cell 11A located at the extremity of the array in the direction in which the ribs 35 protrude. The other extremity side battery cell 11B, located at the extremity of the array on the opposite side from the direction in which the ribs 35 protrude, is in contact with the other restraining member 3 without being mediated by an elastic body 4.

Description

Battery module

The present invention relates to a battery module.

As a conventional battery module, for example, there is a battery module described in Patent Document 1. This conventional battery module includes a laminated body in which battery cells, a battery holder, and an end plate are laminated, a restraining band for restraining the laminated body in a laminating direction, and a plurality of elastic elastic bodies. Has been. The elastic body has elasticity in the stacking direction of the battery cells, and a plurality of the elastic bodies are arranged in a region where the battery cells and the battery holder face each other in the stack.

JP 2009-81056 A

By the way, in the battery module described above, a temperature control member may be interposed between the battery cells from the viewpoint of ensuring the temperature control efficiency of the battery cells. The temperature control member is configured, for example, by arranging a plurality of ribs side by side at a predetermined interval on one surface side of a plate-like base. In this temperature control member, the space surrounded by the rib and the wall surface of the battery cell can be used as a flow path for a temperature control medium or the like by bringing the tip of the rib into contact with the adjacent battery cell.

However, when the above-described temperature control member is interposed between the battery cells, a flow path is not formed with respect to the battery cells positioned at the array end, and the temperature control efficiency of the battery cells positioned at the array end is the same as that of the other battery cells. There is a possibility that the temperature control efficiency is inferior. In the battery module, an elastic body such as rubber may be interposed between the array body and the end plate in order to prevent damage to the battery cell and the restraining member due to the restraining load. Such an elastic body can be disposed at any position between the restraining members for the purpose of preventing the damage of the battery cells and the restraining members, but may be a factor of reducing the temperature control efficiency of the battery cells adjacent to the elastic bodies. . Therefore, in order to make the temperature control efficiency between the battery cells uniform, it is necessary to consider the arrangement position of the elastic body.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a battery module that can achieve uniform temperature control efficiency between battery cells.

In order to solve the above problems, a battery module according to one aspect of the present invention includes an array body in which battery cells are arrayed via a temperature control member, and is disposed so as to sandwich the array body in the array direction of the battery cells. A pair of restraining members for applying a restraining load, and the temperature control member includes a base and a plurality of ribs that protrude to one side of the base and contact adjacent battery cells, and the protruding direction of the ribs An elastic body is disposed between the one end side battery cell positioned at the arrangement end of the first electrode and one of the restraining members, and the other end side battery cell positioned at the arrangement end opposite to the protruding direction of the rib does not interpose the elastic body. In contact with the other of the restraining members.

In this battery module, the elastic body is interposed between the array body and the restraining member, thereby preventing the battery cell and the restraining member from being damaged by the restraining load. In this battery module, an elastic body is disposed between the one end side battery cell positioned at the end of the rib in the protruding direction and the restraining member, but the rib of the temperature control member is in contact with the one end side battery cell. A flow path for the temperature control medium is formed. On the other hand, the rib of the temperature control member is not in contact with the other end side battery cell positioned at the arrangement end opposite to the protruding direction of the rib, and the flow path of the temperature control medium is not formed. Since the restraining member comes into contact with no elastic body, temperature control by heat conduction through the restraining member is possible. Therefore, in this battery module, the variation in the temperature control efficiency of the battery cells located at the end of the array can be reduced, and the temperature control efficiency between the battery cells can be made uniform.

In addition, the battery cells except the one-end battery cell are held by a cell holder to which a temperature control member is fixed so that the rib contacts the adjacent battery cell, and the one-end battery cell is not elastically held by the cell holder. It may be in contact. In this case, the temperature control member can be easily positioned with respect to the battery cell. Moreover, the number of arrangement | positioning of a cell holder can be reduced by omitting the cell holder holding an end battery cell.

Further, the battery cells except the one end side battery cell are held by a cell holder to which the temperature control member is fixed so that the rib contacts the adjacent battery cell, and the one end side battery cell comes into contact with the adjacent elastic body. Thus, the temperature control member may be held by a fixed cell holder. According to such a structure, when expansion | swelling arises in a battery cell and an elastic body compresses and deforms, the space between ribs can be used as an escape part of a deformation | transformation of an elastic body.

Further, a positioning portion for positioning the elastic body may be provided on one of the restraining members. In this case, since the elastic body can be positioned on the restraining member, the assembly work of the array body is facilitated.

The battery module according to one aspect of the present invention can achieve uniform temperature control efficiency between battery cells.

It is the schematic which shows the battery module which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the structure of the battery cell used for the battery module shown in FIG. FIG. 3 is a sectional view taken along line III-III in FIG. 2.

It is the schematic which shows the battery module which concerns on 2nd Embodiment of this invention.

Hereinafter, preferred embodiments of a battery module according to one aspect of the present invention will be described in detail with reference to the drawings.
[First Embodiment]

FIG. 1 is a schematic view showing a battery module according to the first embodiment of the present invention. As shown in the figure, the battery module 1 according to the first embodiment includes an array body 2 in which a plurality of battery cells 11 are arrayed, and a restraining load is applied to the array body 2 in the array direction of the battery cells 11. And an end plate (restraining member) 3 and an elastic body 4 interposed between the array body 2 and the end plate 3.

The array 2 includes six battery cells 11 here. The battery cell 11 is, for example, a lithium ion secondary battery. For example, as shown in FIGS. 2 and 3, the battery cell 11 includes a hollow case 12 having a substantially rectangular parallelepiped shape and an electrode assembly 13 accommodated in the case 12.

The case 12 is formed of a metal such as aluminum, for example, and an organic solvent-based or non-aqueous electrolyte is injected into the case 12, for example. As shown in FIG. 2, the positive terminal 15 and the negative terminal 16 are disposed on the top surface of the case 12 so as to be separated from each other. The positive electrode terminal 15 is fixed to one side in the width direction on the top surface of the case 12 via the insulating member 17, and the negative electrode terminal 16 is fixed to the other side in the width direction on the top surface of the case 12 via the insulating member 18. Has been.

As shown in FIG. 3, the electrode assembly 13 includes, for example, a positive electrode 21, a negative electrode 22, and a bag-like separator 23 disposed between the positive electrode 21 and the negative electrode 22. In the electrode assembly 13, the positive electrode 21 is accommodated in the separator 23, and the positive electrode 21 and the negative electrode 22 are alternately stacked via the separator 23 in this state.

The positive electrode 21 has a metal foil 21a made of, for example, aluminum foil, and a positive electrode active material layer 21b formed on both surfaces of the metal foil 21a. The positive electrode active material layer 21b is formed including a positive electrode active material and a binder. Examples of the positive electrode active material include composite oxide, metallic lithium, and sulfur. The composite oxide includes, for example, at least one of manganese, nickel, cobalt, and aluminum and lithium. A tab 21 c is formed on the upper edge portion of the positive electrode 21 corresponding to the position of the positive electrode terminal 15. The tab 21 c extends upward from the upper edge portion of the positive electrode 21 and is connected to the positive electrode terminal 15 via the conductive member 24.

Meanwhile, the negative electrode 22 includes a metal foil 22a made of, for example, copper foil, and a negative electrode active material layer 22b formed on both surfaces of the metal foil 22a. The negative electrode active material layer 22b is formed including a negative electrode active material and a binder. Examples of the negative electrode active material include carbon such as graphite, highly oriented graphite, mesocarbon microbeads, hard carbon, and soft carbon, alkali metals such as lithium and sodium, metal compounds, SiOx (0.5 ≦ x ≦ 1.5 ) And the like, and boron-added carbon. A tab 22 c is formed at the upper edge of the negative electrode 22 in correspondence with the position of the negative electrode terminal 16. The tab 22 c extends upward from the upper edge portion of the negative electrode 22, and is connected to the negative electrode terminal 16 through the conductive member 25.

The separator 23 is formed in a bag shape, for example, and accommodates only the positive electrode 21 therein. Examples of the material for forming the separator 23 include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), a woven fabric or a nonwoven fabric made of polypropylene, polyethylene terephthalate (PET), methylcellulose, and the like. The separator 23 is not limited to a bag shape, and a sheet shape may be used.

The end plate 3 is a metal plate member, for example. As shown in FIG. 1, the end plate 3 has an area larger than the area when the battery cell 11 is viewed from the arrangement direction, for example, and the outer edge portion of the end plate 3 is larger than the outer edge portion of the battery cell 11. In an overhanging state, the array body 2 and the elastic body 4 are disposed at both ends in the array direction. A plurality of bolts 5 are inserted through outer edge portions of the

end plates

3 and 3. When the nut 6 is screwed onto the tip of each bolt 5 from the outside of the end plate 3, the battery cell 11 and the elastic body 4 are sandwiched and unitized, and a restraining load is applied.

The elastic body 4 is a member used for the purpose of preventing the battery cell 11 and the end plate 3 from being damaged by a restraining load when the battery cell 11 is expanded. As shown in FIG. 1, the elastic body 4 is formed in a rectangular plate shape having a thickness equal to or greater than the thickness of the end plate 3 by, for example, a urethane rubber sponge. Examples of the material for forming the elastic body 4 include ethylene propylene diene rubber (EPDM), chloroprene rubber, and silicon rubber.

Subsequently, the configurations of the array body 2 and the elastic body 4 described above will be described in more detail.

As shown in FIG. 1, a cell holder 31 is attached to the battery cell 11. The cell holder 31 has a frame body 32 that is integrally formed of resin, for example. The frame body 32 is fitted in the case 12 so as to be along each side surface of the case 12 of the battery cell 11 except for the side surface in the arrangement direction of the battery cells 11.

Further, a temperature control member 33 is provided on one side of the frame 32 of the cell holder 31. The temperature control member 33 is formed of a resin such as polypropylene, for example, and has a plate-like base 34 and a plurality of rectangular cross-section ribs 35 formed on one side of the base 34 at equal intervals. The temperature control member 33 has the base 34 attached to the cell holder 31 such that the other surface side without the rib 35 is in contact with the battery cell 11 and the rib 35 faces outward and extends in the width direction of the battery cell 11 (the depth direction in FIG. 1). It is attached to the cell holder 31 by being fitted into the frame body 32 of this. The temperature control member 33 may be integrally formed with the frame body 32 of the cell holder 31.

In the array body 2, the outward ribs 35 protrude outward from the frame body 32, and the tips of the ribs 35 are in contact with the case 12 of the adjacent battery cell 11. Therefore, a space S surrounded by the base 34, the

ribs

35 and 35, and the case 12 of the battery cell 11 is formed between the

adjacent battery cells

11 and 11. This space S is used as a flow path through which a temperature control medium such as cooled air flows, and contributes to temperature control of the adjacent battery cells 11.

As described above, in the configuration in which the outward rib 35 is brought into contact with the adjacent battery cell 11, the battery cell 11 (hereinafter referred to as “one end battery cell 11 A”) positioned at the arrangement end in the protruding direction of the rib 35 is used. There are ribs 35 that come into contact with the case 12, but the battery cells 11 (hereinafter referred to as “other end side battery cells 11 B”) located at the arrangement end opposite to the protruding direction of the ribs 35 come into contact with the case 12. The rib 35 does not exist. Therefore, the space S surrounded by the base 34, the

ribs

35 and 35, and the case 12 of the battery cell 11 is formed in contact with the case 12 in the battery cell 11A on the one end side, whereas the battery cell 11B on the other end side is formed. The space S is not formed in contact with the case 12, and the temperature control efficiency of the other battery cell 11 B may be inferior to the temperature control efficiency of the other battery cells 11.

The elastic body 4 can be disposed at any position between the

end plates

3 and 3 from the viewpoint of preventing damage to the battery cell 11 and the end plate 3. It can be a factor that lowers the temperature control efficiency. Therefore, in order to make the temperature control efficiency between the

battery cells

11 and 11 uniform, it is necessary to consider the arrangement position of the elastic body 4.

On the other hand, in the battery module 1, as shown in FIG. 1, the elastic body 4 is arranged between the one end side battery cell 11 A located at the arrangement end in the protruding direction of the rib 35 and one of the end plates 3. The other end side battery cell 11B located at the arrangement end opposite to the protruding direction of 35 is in contact with the other end plate 3 without the elastic body 4 interposed therebetween.

In the present embodiment, each battery cell 11 except for the one end side battery cell 11 A is held by the cell holder 31 to which the temperature control member 33 having the outward rib 35 is fixed, and the one end side battery cell 11 A is held by the cell holder 31. In the state which is not carried out, it arrange | positions at the arrangement | sequence end of the array body 2. A space S through which the temperature control medium can flow is formed by contacting the rib 35 of the temperature control member 33 on one surface (surface facing the center of the array) of the case 12 of the one end side battery cell 11A. On the side facing the end, the elastic body 4 is in direct contact with substantially the entire surface.

The elastic body 4 is located between the one end side battery cell 11A and the end plate 3. The end plate 3 that contacts the elastic body 4 is provided with a positioning portion 37 for positioning the elastic body 4. The positioning portion 37 is a rectangular frame formed according to the size of the elastic body 4 using, for example, metal or resin, and is provided integrally with the end plate 3. The elastic body 4 is held by the end plate 3 in a state where the elastic body 4 is fitted in the positioning portion 37.

On the other hand, the base 34 of the temperature control member 33 fixed to the cell holder 31 that holds the other end side battery cell 11B is provided on the surface of the case 12 of the other end side battery cell 11B (the surface facing the center of the array). The end plate 3 directly contacts the entire surface of the other surface (surface facing the array end) of the other end side battery cell 11B without the elastic body 4 interposed therebetween. ing.

As described above, in the battery module 1, the elastic body 4 is interposed between the array body 2 and the end plate 3, thereby preventing the battery cell 11 and the end plate 3 from being damaged by a restraining load. . In the battery module 1, the elastic body 4 is disposed between the end plate 3A and the end plate 3 positioned at the end of the rib 35 in the protruding direction. The ribs 35 of the control member 33 come into contact with each other to form a temperature control medium flow path.

On the other hand, the rib 35 of the temperature control member 33 is not in contact with the other end side battery cell 11B located at the arrangement end opposite to the protruding direction of the rib 35, and the flow path of the temperature control medium is not formed. Since the end plate 3 is in contact with the battery cell without the elastic body 4, temperature control by heat conduction through the end plate 3 is possible. Therefore, in the battery module 1, the variation in the temperature control efficiency of the

battery cells

11A and 11B located at the end of the array can be reduced, and the temperature control efficiency between the battery cells 11 can be made uniform.

In the battery module 1, the battery cells 11 other than the one-end battery cell 11 A are held by the cell holder 31 to which the temperature control member 33 is fixed so that the rib 35 contacts the adjacent battery cell 11. 11A is in contact with the elastic body 4 without being held by the cell holder 31. According to such a configuration, the temperature control member 33 can be easily positioned with respect to the battery cell 11. By positioning the space S formed by the temperature control member 33 so as to correspond to a portion (for example, the electrode assembly 13) where heat is generated in the battery cell 11, the temperature control of the battery cell 11 can be suitably performed. Moreover, the number of arrangement | positioning of the cell holder 31 can be reduced by abbreviate | omitting the cell holder 31 holding 11A of one end side battery cells.

One of the restraining members may be provided with a positioning portion for positioning the elastic body. In this case, since the elastic body can be positioned on the restraining member, the assembly work of the array body is facilitated.
[Second Embodiment]

FIG. 4 is a schematic view showing a battery module according to the second embodiment of the present invention. As shown in the figure, the battery module 41 according to the second embodiment is the first embodiment in which the one end side battery cell 11A is not held by the cell holder 31 in that the one end side battery cell 11A is held by the cell holder 31. It is different from the form. In the battery module 41, the one end side battery cell 11A is held by the cell holder 31, and the outward rib 35 of the temperature control member 33 fixed to the cell holder 31 contacts the elastic body 4 adjacent to the one end side battery cell 11A. ing.

Even in such a battery module 41, the elastic body 4 is disposed between the end plate 3 and the one end battery cell 11A located at the end of the rib 35 in the protruding direction. The ribs 35 of the temperature control member 33 come into contact with each other to form a temperature control medium flow path. On the other hand, the rib 35 of the temperature control member 33 is not in contact with the other end side battery cell 11B located at the arrangement end opposite to the protruding direction of the rib 35, and the flow path of the temperature control medium is not formed. Since the end plate 3 is in contact with the battery cell without the elastic body 4, temperature control by heat conduction through the end plate 3 is possible. Therefore, also in the battery module 41, variation in the temperature control efficiency of the

battery cells

In the battery module 41, the battery cells 11 except for the one-end battery cell 11 A are held by the cell holder 31 to which the temperature control member 33 is fixed so that the rib 35 contacts the adjacent battery cell 11. 11A is held by a cell holder 31 to which the temperature control member 33 is fixed so that the rib 35 contacts the adjacent elastic body 4. Thereby, when expansion | swelling arises in the battery cell 11 and the elastic body 4 compresses and deforms, the space S between the

ribs

35 and 35 can be used as an escape part of a deformation | transformation of the elastic body 4. FIG. Therefore, a sudden increase in stress applied to the battery cell 11 and the end plate 3 is suppressed, and damage to the battery cell 11 and the end plate 3 can be prevented more reliably.

The present invention is not limited to the above embodiment. For example, in the above embodiment, the

end plates

3 and 3 are fastened with the bolts 5 and the nuts 6 to apply a restraining load to the array body 2 and the elastic body 4. Plate and the like, and both ends of the restraint band may be fastened to the

end plates

3 and 3 with bolts or the like, respectively, and a restraint load may be applied to the array body 2 and the elastic body 4. Moreover, in the said embodiment, although the temperature control member 33 is being fixed to the cell holder 31, the temperature control member 33 does not necessarily need to be fixed to the cell holder 31. FIG.

Note that examples of temperature control via the end plate 3 include a configuration in which a cooling device is attached to the end plate 3 and a configuration in which the end plate 3 is connected to another heat radiating member. Moreover, it is good also as a structure which makes the end plate 3 L-shape integral with a bracket and radiates heat to the housing | casing used as the fixation destination of the

battery modules

1 and 41 through a bracket.

DESCRIPTION OF

SYMBOLS

1,41 ... Battery module, 2 ... Array, 3 ... End plate (restraint member), 4 ... Elastic body, 11 ... Battery cell, 11A ... One end side battery cell, 11B ... Other end side battery cell, 31 ... Cell holder, 33 ... temperature control member, 34 ... base, 35 ... rib, 37 ... positioning part.

Claims

An array of battery cells arranged via a temperature control member;
A pair of restraining members arranged to sandwich the array and applying a restraining load in the array direction of the battery cells,
The temperature control member includes a base and a plurality of ribs that protrude to one side of the base and contact adjacent battery cells;
An elastic body is disposed between the one end side battery cell located at the arrangement end in the protruding direction of the rib and one of the restraining members,
The battery module in which the other end side battery cell located at the arrangement end opposite to the protruding direction of the rib is in contact with the other of the restraining members without the elastic body.
The battery cells excluding the one end side battery cell are held by a cell holder to which the temperature control member is fixed so that the rib contacts an adjacent battery cell,
The battery module according to claim 1, wherein the one-end battery cell is in contact with the elastic body in a state where the battery cell is not held by the cell holder.
The battery cells excluding the one end side battery cell are held by a cell holder to which the temperature control member is fixed so that the rib contacts an adjacent battery cell,
2. The battery module according to claim 1, wherein the one end side battery cell is held by a cell holder to which the temperature control member is fixed so that the rib contacts the adjacent elastic body.
The battery module according to any one of claims 1 to 3, wherein a positioning portion for positioning the elastic body is provided on one of the restraining members.