JP2020135920A - On-vehicle battery pack - Google Patents

Abstract

To provide an on-vehicle battery pack capable of appropriately collecting dew condensation water generated in a cooling pipe extended in a battery case.SOLUTION: The on-vehicle battery pack has a configuration in which a cooling pipe 50 in which a cooling medium circulates is arranged in a battery case 13, a bottom of the battery case 13 is provided with a groove portion 70, continuously corresponding to the cooling pipe 50, for receiving dew condensation water generated in the cooling pipe 50, and the groove portion 70 is provided with collecting means 80 for collecting the dew condensation water.SELECTED DRAWING: Figure 5

Description

The present invention relates to an in-vehicle battery pack mounted on an electric vehicle.

For example, an electric vehicle having an electric motor as a drive source, such as an electric vehicle or a hybrid vehicle, is equipped with a battery pack for supplying power to the electric motor. The battery pack includes a plurality of battery cells (batteries) and a battery case accommodating the plurality of battery cells, and each battery cell is electrically connected in the battery case.

In a battery pack having such a configuration, the temperature of the battery cell rises, for example, when electric power is consumed by running an electric vehicle or when the battery cell is charged. Therefore, it is necessary to appropriately cool each battery cell housed in the battery case.

As a configuration for cooling the battery cell, for example, a cooling pipe (refrigerant flow path, refrigerant passage) is provided in the battery case, and a cooling medium (cooling gas, etc.) is circulated in the cooling pipe, so that the inside of the battery case is cooled. Some are designed to cool the battery cell (see, for example, Patent Documents 1 and 2).

Japanese Patent No. 6099772 Japanese Unexamined Patent Publication No. 2016-91951

As described above, the battery cells in the battery case can be cooled by providing the battery case with a cooling pipe for circulating the cooling medium. However, by circulating the cooling medium, dew condensation water may be generated on the surface of the cooling pipe, and due to this dew condensation water, for example, metal parts are corroded (rust is generated), and so on. There is a risk that a problem will occur.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an in-vehicle battery pack capable of appropriately recovering dew condensation water generated in a cooling pipe extending in a battery case. To do.

One aspect of the present invention that solves the above problems is an in-vehicle battery pack that includes a plurality of battery cells and a battery case in which these battery cells are housed, and is mounted on an electric vehicle. A cooling pipe through which the cooling medium circulates is arranged in the battery case, and a groove portion is provided at the bottom of the battery case, which is continuously provided corresponding to the cooling pipe and receives condensed water generated in the cooling pipe. The in-vehicle battery pack is characterized in that the groove portion is provided with a recovery means for recovering the condensed water.

In the vehicle-mounted battery pack of the present invention, the condensed water generated in the cooling pipe circulates in the groove and is collected by the collecting means. Therefore, the adhesion of condensed water to other parts in the battery pack is suppressed.

Here, it is preferable that the cooling pipe is provided in contact with the side surface of the groove. As a result, the condensed water generated in the cooling pipe can easily flow into the groove from the portion in contact with the side surface of the groove.

Further, as the recovery means, for example, a discharge unit for discharging the condensed water to the outside can be mentioned. Alternatively, a desiccant that absorbs the condensed water can be mentioned. By providing such a recovery means in the groove, the condensed water can be recovered more appropriately.

Further, it is preferable that the collecting means is provided at one end of the electric vehicle in the front-rear direction. In this configuration, the dew condensation water in the groove can easily flow into the recovery means due to the load during acceleration or deceleration of the electric vehicle.

Further, the opening width of the groove is preferably wider than the diameter of the cooling pipe. As a result, the condensed water will flow more reliably into the groove. That is, it is possible to more reliably prevent the condensed water generated on the surface of the cooling pipe from flowing out of the groove.

Further, the width of the groove is preferably narrower toward the bottom side of the groove. More specifically, it is preferable that the groove portion is formed in a so-called V-groove shape. As a result, even when the amount of condensed water is relatively small, the condensed water in the groove can be circulated to the recovery means.

As described above, according to the battery pack according to the present invention, the condensed water can be appropriately recovered in the battery case, and the occurrence of problems caused by the condensed water can be suppressed.

It is a figure which shows an example of the usage mode of a battery pack. It is a perspective view which shows the schematic structure of the battery pack. It is a perspective view which shows the schematic structure of the battery module included in the battery pack. It is a figure which shows the appearance of the battery cell which comprises the battery module. It is a top view which shows the schematic structure of the pack tray which concerns on one Embodiment of this invention. It is sectional drawing of the pack tray which concerns on one Embodiment of this invention. It is sectional drawing of the pack tray which concerns on one Embodiment of this invention. It is sectional drawing explaining the modification of the battery pack which concerns on one Embodiment of this invention. It is sectional drawing explaining the modification of the battery pack which concerns on one Embodiment of this invention. It is sectional drawing explaining the modification of the battery pack which concerns on one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The vehicle 1 shown in FIG. 1 is, for example, an electric vehicle such as an electric vehicle or a hybrid vehicle, and is an in-vehicle battery pack (hereinafter, simply referred to as a battery pack) 10 for supplying power to an electric motor (motor) (not shown). Is installed.

As shown in FIG. 2, the battery pack 10 includes a battery case 13 including a pack tray 11 and a pack cover 12, and a battery module 20 housed in the battery case 13.

As shown in FIGS. 2 and 3, a plurality of battery modules 20 are housed in the battery pack 10 (inside the battery case 13), and each battery module 20 contains a plurality of battery cells (secondary batteries) 30. I have. The number of battery cells 30 included in the battery module 20 is not particularly limited.

Here, each battery cell 30 constituting the battery module 20 is, for example, a sealed secondary battery which is a lithium ion battery, and as shown in FIG. 4, the container 31 and the lid member for sealing the container 31 are sealed. 32 and. Inside the container 31, an electrode body (power generation element) including a positive electrode plate, a negative electrode plate, and a separator is housed together with an electrolytic solution. Since the structure of each member housed in the container 31 is known, detailed description thereof will be omitted. Further, the lid member 32 is provided with a positive electrode terminal member 33 and a negative electrode terminal member 34, which are connected to the positive electrode plate or the negative electrode plate of the electrode body housed in the container 31, respectively.

The battery pack 10 according to the present invention is provided with a cooling pipe 50 through which a cooling medium (refrigerant gas, cooling water, etc.) flows in order to cool such a plurality of battery cells 30.

As shown in FIGS. 5 to 7, one cooling pipe 50 for cooling the battery cell 30 is meanderingly extended along the bottom surface of the pack tray 11 in the pack tray 11. 5 is a top view of the pack tray 11, FIG. 6 is a cross-sectional view taken along the line AA'of FIG. 5, and FIG. 7 is a cross-sectional view taken along the line BB'of FIG.

Although not shown, the cooling pipe 50 is connected to the outside of the pack tray 11 by a connecting pipe, and the cooling medium is circulated through the connecting pipe to the cooling pipe 50. In addition, the connection pipe is provided with a heat exchange section. The heat exchange unit includes, for example, a compressor, a capacitor, or the like, and cools a cooling medium whose temperature has risen in the battery pack 10. The configuration of the heat exchange unit is not particularly limited, and a known configuration may be adopted.

A cooling plate 60 made of a metal plate or the like is provided above the cooling pipe 50 extending in the pack tray 11 in this way, and the battery module 20 including the plurality of battery cells 30 is the cooling plate 60. It is fixed on top.

The cooling plate 60 is preferably provided in contact with the cooling pipe 50, but may be provided close enough to be cooled by the cooling pipe 50. Further, the cooling plate 60 does not necessarily have to be provided.

Further, a groove 70 is provided at the bottom of the pack tray 11, that is, on the lower side of the cooling pipe 50. The groove 70 is for receiving and circulating the dew condensation water generated on the surface of the cooling pipe 50, and is continuously provided at a position corresponding to the cooling pipe 50 extending in the pack tray 11.

The groove 70 is provided with a discharge section (recovery means) 80 for recovering the condensed water flowing in the groove 70. A recess 75 having a depth deeper than the other portion is formed in a part of the groove 70, and the discharge portion 80 is provided in the recess 75.

In the present embodiment, the discharge portion 80 is configured to include a discharge port 81 provided so as to penetrate the bottom surface of the recess 75, and an opening / closing member 82 for opening / closing the discharge port 81. Then, for example, when a predetermined amount of dew condensation water is accumulated in the recess 75, the opening / closing member 82 is operated at a predetermined timing to open the discharge port 81, and the dew condensation water is discharged to the outside from the discharge port 81. It has become. That is, the discharge unit 80, which is a collection means, discharges the condensed water in the groove 70 to the outside of the battery pack 10 from the discharge port 81 and collects it.

The mechanism for moving the opening / closing member 82 is not particularly limited. Further, the opening / closing member 82 does not necessarily have to be provided. That is, the condensed water may be always discharged from the discharge port 81.

The discharging portion (collecting means) 80 may be provided at any position of the groove portion 70, but it is preferable that the discharging portion (collecting means) 80 is provided near one end portion in the front-rear direction of the electric vehicle 1. In the present embodiment, the discharge portion 80 is provided near the rear end portion of the electric vehicle 1 in the groove portion 70. As a result, the dew condensation water in the groove 70 is easily discharged from the discharge port 81 due to the load of the electric vehicle 1 during acceleration.

By the way, when the discharge portion 80 is provided near the front end portion of the electric vehicle 1 in the groove portion 70, the dew condensation water in the groove portion 70 is likely to be discharged from the discharge port 81 due to the load during acceleration of the electric vehicle 1. Become.

In the configuration in which the cooling pipe 50 is provided in the battery case 13 in this way, the groove 70 corresponding to the cooling pipe 50 is continuously provided at the bottom of the pack tray 11, and the condensed water flowing through the groove 70 is collected. By providing the discharge unit (recovery means) 80 for this purpose, the condensed water in the battery case 13 can be appropriately recovered, and the occurrence of defects in the battery pack 10 due to the condensed water can be suppressed. it can.

Here, the opening width W1 of the groove 70 is preferably wider than the diameter d1 of the cooling pipe 50 (see FIG. 6). In other words, the cooling pipe 50 is preferably arranged in the region facing the groove 70.

Further, the cooling pipe 50 may be provided above the groove 70, but it is preferable that a part of the cooling pipe 50 is provided in the groove 70. Specifically, it is preferable that the cooling pipe 50 is provided so that the center thereof is located in the groove 70. Further, as shown in FIG. 8, it is preferable that the cooling pipe 50 is in contact with the side surface of the groove 70. That is, it is desirable that the cooling pipe 50 is arranged within a range facing the groove 70 and is in contact with the side surface of the groove 70. With such a configuration, the condensed water generated on the surface of the cooling pipe 50 can be more reliably flowed into the groove 70.

The shape of the groove 70 is not particularly limited, but it is preferable that the groove 70 is formed so that the width of the groove 70 becomes narrower toward the bottom side. For example, as shown in FIG. 9, the groove 70 is formed into a so-called V-groove shape. Is preferable. As a result, even when the amount of dew condensation water flowing into the groove 70 is small, the cooling water is likely to collect, and the dew condensation water can be easily distributed to the discharge portion 80.

In the present embodiment, a configuration in which the discharge unit 80 is provided as the collection means is illustrated, but the collection means is not limited to this. The recovery means may be any structure as long as it can recover the condensed water in the groove 70, and may be, for example, a desiccant that absorbs the condensed water. For example, instead of the discharge unit 80, a desiccant as a recovery means may be installed in the recess 75. Even if the dew condensation water in the groove 70 is recovered by the desiccant in this way, it is possible to suppress the occurrence of defects in the battery pack due to the dew condensation water.

Further, in the present embodiment, a configuration in which the cooling pipe 50 is provided at the bottom of the pack tray 11, that is, on the lower side of the battery module 20 (battery cell 30) is illustrated, but the arrangement of the cooling pipe 50 is limited to this. is not.

For example, as shown in FIG. 10, the cooling pipe 50 may be provided so as to surround the battery module 20. Even in this case, since the groove 70 is continuously provided on the lower side of the cooling pipe 50 corresponding to the cooling pipe 50, the condensed water can be satisfactorily recovered as described above.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment. The present invention can be appropriately modified without departing from the spirit of the present invention.

For example, in the above-described embodiment, a configuration in which one cooling pipe is extended in the pack tray is illustrated, but in the pack tray, there are a plurality of cooling pipes in which cooling media are independently distributed. It may be extended.

Further, the flow path area of the cooling pipe extending in the pack tray may be substantially constant in the flow direction of the cooling medium, but the flow path area becomes wider toward the downstream side in the flow direction of the cooling medium. May be good. Since the temperature of the cooling medium flowing through the cooling pipe becomes higher toward the downstream side in the flow direction, each battery cell in the battery case can be cooled more uniformly by gradually changing the flow path area in this way. ..

1 Electric vehicle (vehicle)
10 Battery pack 11 Pack tray 12 Pack cover 13 Battery case 20 Battery module 30 Battery cell 31 Container 32 Lid member 50 Cooling pipe 60 Cooling plate 70 Groove 75 Recess 80 Discharge (collection means)
81 Discharge port 82 Opening and closing member

Claims (7)

An in-vehicle battery pack that includes a plurality of battery cells and a battery case in which these battery cells are housed, and is mounted on an electric vehicle.
A cooling pipe through which the cooling medium circulates is arranged in the battery case.
The bottom of the battery case is provided with a groove that is continuously provided corresponding to the cooling pipe and receives the condensed water generated in the cooling pipe.
An in-vehicle battery pack characterized in that the groove portion is provided with a recovery means for recovering the condensed water. The vehicle-mounted battery pack according to claim 1.
An in-vehicle battery pack characterized in that the cooling pipe is provided in contact with the side surface of the groove. The vehicle-mounted battery pack according to claim 1 or 2.
The vehicle-mounted battery pack is characterized in that the collecting means is a discharging unit for discharging the condensed water to the outside. The vehicle-mounted battery pack according to any one of claims 1 to 3.
The vehicle-mounted battery pack is characterized in that the recovery means is a desiccant that absorbs the condensed water. The vehicle-mounted battery pack according to any one of claims 1 to 4.
An in-vehicle battery pack characterized in that the collecting means is provided at one end of the electric vehicle in the front-rear direction. The vehicle-mounted battery pack according to any one of claims 1 to 5.
An in-vehicle battery pack characterized in that the opening width of the groove is wider than the diameter of the cooling pipe. The vehicle-mounted battery pack according to any one of claims 1 to 6.
An in-vehicle battery pack characterized in that the width of the groove is narrower toward the bottom side of the groove.

Images