JP2020198175A - Battery module - Google Patents

Abstract

To provide a battery module capable of cooling a battery module while further miniaturizing or omitting a forced cooling structure or a cooling refrigerant passage.SOLUTION: A battery module includes: at least one of battery cells, each including a terminal; a housing for storing at least one battery cell; an insulating layer interposed between the terminal and the housing; and a pressing member for applying a pressing force to at least one battery cell so that a heat conduction path is formed, which extends from the terminal of the battery cell stored in the housing to the housing.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to battery modules.

In recent years, in order to promote the use of rechargeable and dischargeable secondary batteries, various battery modules have been developed in which battery cells are closely arranged and used in module units to increase the density and reduce the installation area. For example, Patent Document 1 discloses a configuration example relating to such a battery module.

Japanese Unexamined Patent Publication No. 2015-22935

By the way, a secondary battery usually generates heat during charging and discharging, so an appropriate cooling means is required. As the cooling means, for example, a cooling refrigerant such as air or water is circulated to suppress the temperature rise of the battery cell during charging and discharging, and the battery cell is cooled uniformly. Here, when considering a higher density of the battery module, if the forced cooling structure and the cooling refrigerant flow path can be further miniaturized or omitted, the installation space can be further reduced.

In this regard, Patent Document 1 does not disclose any knowledge regarding cooling the battery module while further reducing or omitting the forced cooling structure and the cooling refrigerant flow path.

In view of the above circumstances, at least one embodiment of the present disclosure aims to provide a battery module capable of cooling a battery module while further reducing or omitting a forced cooling structure and a cooling refrigerant flow path. To do.

(1) The battery module according to at least one embodiment of the present invention is
With at least one battery cell, each containing a terminal,
A housing that houses at least one battery cell and
An insulating layer interposed between the terminal and the housing,
A pressing member that applies pressing force to at least one battery cell so as to form a heat conduction path from the terminal of the battery cell housed in the housing to the housing.
Is equipped with.

According to the configuration of (1) above, by pressing the battery cell against the housing by the pressing member, the terminals are pressed toward the housing, and a heat conduction path from the terminals to the housing is formed. As a result, the heat generated in the battery cell during charging / discharging can be released to the outside of the battery module housing via the heat conduction path. Therefore, for example, the battery module can be efficiently cooled even when the configuration for forced cooling cannot be incorporated in the housing or is omitted.

(2) In some embodiments, in the configuration of (1) above,
The housing may be configured to accommodate the battery cells horizontally with the terminals facing sideways.

According to the configuration of (2) above, the effect described in (1) above can be enjoyed in the battery module in which the battery cells are horizontally housed in the housing with the terminals facing sideways.

(3) In some embodiments, in the configuration of (2) above,
The at least one battery cell includes a plurality of battery cells.
The housing may include support shelves for accommodating each of the plurality of battery cells at intervals in the thickness direction.

According to the configuration of (3) above, since a plurality of battery cells are arranged at intervals in the thickness direction by the support shelf, even when a plurality of battery cells are housed in the housing, one battery cell is provided. No load of multiple battery cells is applied to the battery cells. Therefore, it is possible to provide a battery module that does not generate a load due to a load on each battery cell while accommodating a plurality of horizontally placed battery cells in the housing. Further, since a gap can be secured between the battery cells by using the support shelf as a spacer, the gap can be used as, for example, a refrigerant flow path.

(4) In some embodiments, in the configuration of (3) above,
The battery module further includes a bus bar between the terminal and the housing that electrically connects the terminal of one battery cell among the plurality of battery cells and the terminal of the other battery cell.
The heat conduction path may be formed from the terminal to the housing via the bus bar and the insulating layer.

According to the configuration of (4) above, a heat conduction path is formed from the terminal to the housing via the bus bar. Then, the heat generated during charging / discharging can be efficiently discharged to the outside of the housing via the terminals and the bus bar.

(5) In some embodiments, in the configuration of (4) above,
The bus bar may contain a metal containing Cu or Al.

According to the configuration of the above (5), the effect described in the above (4) can be enjoyed in the battery module provided with the bus bar containing the metal containing Cu or Al.

(6) In some embodiments, in any one of the above configurations (1) to (5),
A refrigerant flow path through which cooling refrigerant can flow is formed between one end surface of the battery cell provided with the terminal and the inner wall surface of the housing.
The terminal may be surrounded by the refrigerant flow path.

According to the configuration (6) above, in addition to the heat conduction path from the terminal to the housing, a refrigerant flow path formed between one end surface of the battery cell provided with the terminal and the inner wall surface of the housing is provided. The flowing cooling refrigerant can remove heat generated during charging and discharging more efficiently.

(7) In some embodiments, in the configuration of (6) above,
An outlet opening that communicates with the refrigerant flow path may be formed between the pressing member or the pressing member and the housing.

According to the configuration (7) above, the heat generated during charging / discharging is generated by providing the pressing member or the outlet opening that communicates with the refrigerant flow path in the housing between the pressing member and the housing. , In addition to the heat conduction path from the terminal to the housing, it can be discharged to the outside of the housing via the cooling refrigerant flowing out from the outlet opening.

(8) In some embodiments, in any one of the above configurations (1) to (7),
The pressing member may include a fastening member or an elastic member.

According to the configuration of (8) above, the pressing member including the fastening member or the elastic member applies the pressing force to the battery cell. Therefore, for example, by appropriately adjusting the fastening force of the fastening member and the urging force of the elastic member, the pressing force applied to the battery cell and, by extension, the pressing force of the terminal against the housing can be appropriately adjusted. ..

(9) In some embodiments, in any one of the above configurations (1) to (8),
The insulating layer may contain a highly thermally conductive resin having a thermal conductivity of 1.5 W / mK or more.

According to the configuration of (9) above, the insulating layer contains a high thermal conductive resin having a thermal conductivity of 1.5 W / mK or more, so that the insulation between the terminal and the housing is ensured from the terminal. Since it is possible to secure a heat conduction path capable of efficiently transferring heat to the housing, it is possible to secure both the insulation between the terminal and the housing and the conductivity.

(10) In some embodiments, in any one of the above configurations (1) to (9),
The terminal includes a positive electrode terminal and a negative electrode terminal.
The insulating layer may be configured to be in contact with the positive electrode terminal and the negative electrode terminal.

According to the configuration (10) above, since both the positive electrode terminal and the negative electrode terminal of the battery cell are in contact with the insulating layer, it is possible to suppress the occurrence of an electrical short circuit between the positive electrode terminal and the negative electrode terminal.

(11) In some embodiments, in any one of the above (4) or (5) configurations.
The insulating layer may be provided so as to cover the surface of the bus bar.

According to the configuration of (11) above, the electrical insulation between the terminal and the housing can be ensured by the insulating layer provided so as to cover the surface of the bus bar.

According to at least one embodiment of the present disclosure, it is possible to provide a battery module capable of cooling the battery module while further reducing or omitting the forced cooling structure and the cooling refrigerant flow path.

It is a top view which shows the structural example of the battery module which concerns on one Embodiment of this disclosure. It is a side sectional view which shows the battery module which concerns on one Embodiment. It is a top view which shows the structure of the battery module which concerns on other embodiment. It is a top view which shows the structural example of the holding member in another embodiment. It is a top view which shows the structural example of the holding member in another embodiment.

Hereinafter, some embodiments of the present invention will be described with reference to the drawings. However, the scope of the present invention is not limited to the following embodiments. The dimensions, materials, shapes, numbers, relative arrangements, and the like of the components described in the following embodiments are not intended to limit the scope of the present invention to that alone, but are merely explanatory examples.

First, a schematic configuration of the battery module according to the embodiment of the present disclosure will be described.
FIG. 1 is a plan view showing a configuration example of a battery module according to an embodiment of the present disclosure. FIG. 2 is a side sectional view showing a battery module according to an embodiment.
The battery module 1 can be mounted on, for example, an electric vehicle, an industrial vehicle such as a battery-powered forklift, or an industrial machine such as an electric machine operated by electric power.
Such a battery module 1 includes, for example, as illustrated in FIGS. 1 and 2, each having at least one battery cell 2 including a terminal 3, and a housing 5 accommodating at least one battery cell 2. At least one so as to form an insulating layer 6 interposed between the terminal 3 and the housing 5 and a heat conduction path 8 from the terminal 3 of the battery cell 2 housed in the housing 5 to the housing 5. It includes a pressing member 10 that applies pressing force to the battery cell 2.

The battery cell 2 is not particularly limited, but may include a secondary battery cell having a high energy density such as a lithium ion battery. The battery cell 2 configured as a secondary battery can be charged by connecting an external power source (for example, an external AC power source such as a commercial 100Vac) to the terminal 3, and can supply power by connecting a load to the terminal 3. Has been done. That is, the battery cell 2 is configured to be able to be repeatedly charged and discharged (charged or discharged), and heat is generated during the charging or discharging.
Such a battery cell 2 may be configured to include a so-called square battery cell.
The terminal 3 is arranged at one end of the battery cell 2. In one embodiment, for example, a plurality of terminals 3 including a positive electrode terminal 3A and a negative electrode terminal 3B are arranged on one end surface 2A of the battery cell 2 (the left end surface of the battery cell 2 in FIG. 2). The terminal 3 may be provided so as to be laterally (or horizontally) from one end surface 2A of the square battery cell that faces sideways when the battery cell 2 is arranged horizontally.

The housing 5 is configured to accommodate one or more battery cells 2 inside. The battery module 1 is configured as a secondary battery integrated body by integrating a plurality of battery cells 2 at a high density in the housing 5.

The insulating layer 6 prevents the terminal 3 and the housing 5 from coming into direct contact with each other and electrically insulates the terminal 3 from the housing 5, while the heat between the terminal 3 and the housing 5 is generated. Is configured to enable transmission. That is, the heat conduction path 8 toward the terminal 3, the insulating layer 6, and the housing 5 is formed with the insulating layer 6 interposed therebetween. The material constituting such an insulating layer 6 is not particularly limited.

The pressing member 10 has a width similar to that of the housing 5, and is connected to and fixed to the housing 5 at one end and the other end in the width direction, for example. The pressing member 10 in one embodiment is configured to apply pressing force to the battery cell 2 by fastening its ends (for example, both ends) to the housing 5 via a fastening member or the like. .. In some embodiments, for example, the pressing member 10 is configured to apply pressing pressure to the other end surface of the battery cell 2 so that the terminal 3 of the battery cell 2 is pressed toward the inner wall surface of the housing 5. May be good.

As described above, by pressing the battery cell 2 against the housing 5 by the pressing member 10, the terminal 3 is pressed toward the housing 5 to form the heat conduction path 8 from the terminal 3 to the housing 5. According to this, the heat generated at the terminal 3 of the battery cell 2 during charging / discharging can be discharged to the outside of the housing 5 of the battery module 1 via the heat conduction path 8. Therefore, for example, there is a case where the configuration for forced cooling cannot be incorporated in the housing 5 due to space restrictions due to the high density of the battery cells 2 in the housing 5 or other various circumstances, or when the configuration is omitted. However, the battery module 1 can be efficiently cooled via the heat conduction path 8.

In some embodiments, in the configurations described above, the housing 5 is configured to accommodate the battery cells 2 horizontally with the terminals 3 facing sideways, for example as illustrated in FIGS. 1 and 2. You may be. For example, the housing 5 may be configured to accommodate the square battery cells horizontally so that the shortest side of the square battery cells as the battery cells 2 is along the vertical direction. Alternatively, the housing 5 may accommodate the battery cell 2 so that the surface having the largest area of the surface of the battery cell 2 is arranged sideways (for example, horizontally). When the battery cell 2 is horizontally housed in the housing 5 in this way, the positional relationship between the housing 5 and the battery cell 2 in the housing 5 is as illustrated in FIGS. 1 and 2. However, the arrangement or orientation of the housing 5 itself is not particularly limited. That is, the housing 5 may be arranged so that, for example, the shortest side of the square battery cell as the battery cell 2 is along a direction other than the vertical direction. For example, the battery cell 2 and the housing 5 may be inclined so that one of the front and rear ends is higher than the other end, or the left and right ends are inclined so as to be higher than the other end. May be arranged.

According to the configuration in which the battery cell 2 is horizontally housed in the housing 5 as described above, in the battery module 1 in which the battery cell 2 is horizontally housed in the housing 5 with the terminal 3 facing sideways. You can enjoy the effects described in the above-described embodiment of the present disclosure.

In some embodiments, in the configuration in which the battery cells 2 are arranged horizontally as described above, for example, as illustrated in FIG. 2, at least one battery cell 2 may include a plurality of battery cells 2. Good. In this case, the housing 5 may include a support shelf 30 for accommodating each of the plurality of battery cells 2 at intervals in the thickness direction (or in the vertical direction).
For example, the support shelf 30 may be a rack formed on the inner wall surface of the housing 5. Such a support shelf 30 may extend along the moving direction of the battery cell 2 inserted into the housing 5 (for example, the left-right direction on the paper surface in FIGS. 1 and 2). In some embodiments, the battery cell 2 may be supported only on a portion of the inner wall of the housing 5 that faces each other (for example, the front side of the paper surface and the back side of the paper surface in FIG. 2). The support shelf 30 has a gap between one battery cell 2 arranged above the inside of the housing 5 and another battery cell 2 arranged below (directly below) the one battery cell 2. It may have a function as a spacer for securing the above.

According to the configuration in which the housing 5 includes the support shelf 30, the support shelf 30 arranges the plurality of battery cells 2 at intervals in the thickness direction, so that the plurality of batteries are arranged in the housing 5. Even when the cells 2 are accommodated, the loads of the plurality of battery cells 2 are not applied to one battery cell 2. Therefore, it is possible to provide a battery module 1 that does not generate a load due to a load on each battery cell 2 while accommodating a plurality of horizontally placed battery cells 2 in the housing 5. Further, since the support shelf 30 can be used as a spacer to secure a gap between the battery cells 2, the gap can be used as, for example, the refrigerant flow path 40 (described later).

In some embodiments, in a configuration in which the housing 5 includes a support shelf 30 as described above, the battery module 1 has a terminal 3 and a housing 5 as illustrated, for example, in FIGS. 1 and 2, but not limited to. A bus bar 20 for electrically connecting the terminal 3 of one of the plurality of battery cells 2 and the terminal 3 of the other battery cell 2 is further provided between the two, and the bus bar 20 and the insulating layer 6 are provided from the terminal 3. A heat conduction path 8 may be formed in the housing 5 via the housing 5.
The bus bar 20 is a metal member that connects the batteries when manufacturing the assembled battery.
When a plurality of battery cells 2 are connected in series to form a battery module 1, either one of the positive electrode terminal 3A or the negative electrode terminal 3B of one battery cell 2 is arranged next to the one battery cell 2. It is arranged so as to electrically connect to either the positive electrode terminal 3A or the negative electrode terminal 3B of the battery cell 2 of the above. For example, the positive electrode terminal 3A of one battery cell 2 and the negative electrode terminal 3B of another battery cell 2 arranged next to the one battery cell 2 are arranged so as to be electrically connected (series connection). On the other hand, in another embodiment, each terminal 3 may be connected by a bus bar 20 so that a plurality of battery cells 2 are connected in parallel.

According to the configuration including the bus bar 20 as described above, the heat conduction path 8 from the terminal 3 to the housing 5 via the bus bar 20 is formed. Then, the heat generated at the terminal 3 during charging / discharging can be efficiently discharged to the outside of the housing 5 via the bus bar 20.

In some embodiments, in the configuration with the bus bar 20 as described above, the bus bar 20 may contain a metal containing Cu or Al.

In this way, in the battery module 1 provided with the bus bar 20 containing the metal containing Cu or Al, the effects described in the above-described embodiment of the present disclosure can be enjoyed.

In some embodiments, in any one of the above embodiments, between one end surface 2A of the battery cell 2 provided with the terminal 3 and the inner wall surface 5A of the housing 5, for example, as illustrated in FIG. In addition, a refrigerant flow path 40 through which the cooling refrigerant can flow may be formed. In this case, the terminal 3 may be surrounded by the refrigerant flow path 40.

According to the configuration having the refrigerant flow path 40 as described above, in addition to the heat conduction path 8 from the terminal 3 to the housing 5, one end surface 2A of the battery cell 2 provided with the terminal 3 and the inner wall surface of the housing 5 are provided. The cooling refrigerant flowing through the refrigerant flow path 40 formed between the 5A and the 5A can more efficiently remove the heat generated at the terminal 3 during charging / discharging.

In some embodiments, in the configuration having the above-mentioned refrigerant flow path 40, for example, as illustrated in FIG. 3, the pressing member 10 or the pressing member 10 communicates with the refrigerant flow path 40 between the housing 5. The outlet opening 44 may be formed. That is, the outlet opening 44 may be a through hole formed so as to penetrate the pressing member 10 in the thickness direction.

According to the structure in which the pressing member 10 or the outlet opening 44 communicating with the refrigerant flow path 40 in the housing 5 is provided between the pressing member 10 and the housing 5, the terminal 3 is charged and discharged. The heat generated in the above can be added to the heat conduction path 8 from the terminal 3 to the housing 5 and discharged to the outside of the housing 5 via the cooling refrigerant flowing out from the outlet opening 44.

In some embodiments, in any one of the above embodiments, the pressing member 10 may include a fastening member 11 or an elastic member 12, as illustrated, for example, in FIGS. 1 and 3-5.

As described above, according to the configuration in which the pressing member 10 including the fastening member 11 or the elastic member 12 applies the pressing force to the battery cell 2, for example, the fastening force by the fastening member 11 and the urging force by the elastic member 12 are appropriate. By adjusting to, the pressing force applied to the battery cell 2 and, by extension, the pressing force of the terminal 3 against the housing 5 can be appropriately adjusted.

In some embodiments, in any of the above embodiments, the insulating layer 6 may contain a high thermal conductivity resin having a thermal conductivity of 1.5 W / mK or more.

As described above, according to the configuration in which the insulating layer 6 contains a high thermal conductive resin having a thermal conductivity of 1.5 W / mK or more, the insulation between the terminal 3 and the housing 5 is ensured from the terminal 3. Since it is possible to secure a heat conduction path 8 capable of efficiently transferring heat to the housing 5, it is possible to achieve both insulation and conductivity between the terminal 3 and the housing 5.

In some embodiments, in any of the above embodiments, the terminal 3 may include a positive electrode terminal 3A and a negative electrode terminal 3B, for example, as illustrated in FIGS. 1 and 3-5. In this case, the insulating layer 6 may be configured to be in contact with the positive electrode terminal 3A and the negative electrode terminal 3B.

As described above, according to the configuration in which both the positive electrode terminal 3A and the negative electrode terminal 3B of the battery cell 2 are in contact with the insulating layer 6, it is possible to suppress the occurrence of an electrical short circuit between the positive electrode terminal 3A and the negative electrode terminal 3B. it can.
The insulating layer 6 may be configured to be in contact with each of the positive electrode terminals 3A and the negative electrode terminals 3B over the plurality of battery cells 2. By doing so, the occurrence of a short circuit between the positive electrode terminal 3A and the negative electrode terminal 3B in one battery module 1 can be suppressed by one insulating layer 6, so that the number of parts can be reduced.

In some embodiments, in the configuration including the positive electrode terminal 3A and the negative electrode terminal 3B as described above, the insulating layer 6 may be provided so as to cover the surface of the bus bar 20.
For example, the insulating layer 6 may contain alumite formed as an anodized film on the surface of the bus bar 20 formed containing Al.

As described above, according to the configuration in which the insulating layer 6 is provided so as to cover the surface of the bus bar 20, electrical insulation between the terminal 3 and the housing 5 can be ensured.

According to at least one embodiment of the present disclosure, it is possible to provide a battery module 1 capable of cooling the battery module 1 while further downsizing or omitting the forced cooling structure and the cooling refrigerant flow path 40.

The present invention is not limited to the above-described embodiment, and includes a modified form of the above-described embodiment and a combination of these embodiments.

1 Battery module 2 Battery cell 2A One end surface 3 Terminal 3A Positive electrode terminal 3B Negative electrode terminal 5 Housing 5A Inner wall surface 6 Insulation layer 8 Heat conduction path 10 Pressing member 11 Fastening member 12 Elastic member 20 Bus bar 30 Support shelf 40 Refrigerant flow path 44 Outlet Aperture

Claims (11)

With at least one battery cell, each containing a terminal,
A housing that houses at least one battery cell and
An insulating layer interposed between the terminal and the housing,
A pressing member that applies pressing force to at least one battery cell so as to form a heat conduction path from the terminal of the battery cell housed in the housing to the housing.
Battery module with. The battery module according to claim 1, wherein the housing is configured to accommodate the battery cells horizontally with the terminals facing sideways. The at least one battery cell includes a plurality of battery cells.
The battery module according to claim 2, wherein the housing includes a support shelf for accommodating each of the plurality of battery cells at intervals in the thickness direction. The battery module further includes a bus bar between the terminal and the housing that electrically connects the terminal of one battery cell among the plurality of battery cells and the terminal of the other battery cell.
The battery module according to claim 3, wherein the heat conduction path is formed from the terminal to the housing via the bus bar and the insulating layer. The battery module according to claim 4, wherein the bus bar contains a metal containing Cu or Al. A refrigerant flow path through which cooling refrigerant can flow is formed between one end surface of the battery cell provided with the terminal and the inner wall surface of the housing.
The battery module according to any one of claims 1 to 5, wherein the terminal is surrounded by the refrigerant flow path. The battery module according to claim 6, wherein an outlet opening that communicates with the refrigerant flow path is formed between the pressing member or the pressing member and the housing. The battery module according to any one of claims 1 to 7, wherein the pressing member includes a fastening member or an elastic member. The battery module according to any one of claims 1 to 8, wherein the insulating layer contains a high thermal conductivity resin having a thermal conductivity of 1.5 W / mK or more. The terminal includes a positive electrode terminal and a negative electrode terminal.
The battery module according to any one of claims 1 to 9, wherein the insulating layer is configured to be in contact with the positive electrode terminal and the negative electrode terminal. The battery module according to claim 4 or 5, wherein the insulating layer is provided so as to cover the surface of the bus bar.

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