JP2023183630A - Battery temperature control device - Google Patents

Abstract

To suppress variation in temperature of each battery.SOLUTION: A refrigeration cycle 11 further includes a partition wall 74 for performing heat-exchange between refrigerant flowing in a first main flow path 52 and refrigerant flowing in a second main flow path 62. In a battery cooling mode, liquefied refrigerant is distributed from the first main flow path 52 to each of first individual flow paths 51, so that the liquefied refrigerant is easily distributed to each battery heat-exchanger 15 evenly. In a battery warm-up mode, refrigerant which has been fallen into a gas-liquid two-phase state is distributed from the second main flow path 62 to each of second individual flow paths 61, so that the refrigerant in the gas-liquid two-phase state is distributed to each battery heat-exchanger 15. Since the temperature difference between the refrigerant flowing in each battery heat-exchanger 15 and each battery 20 is maintained, each battery 20 is warmed up uniformly as a whole.SELECTED DRAWING: Figure 1

Description

The present invention relates to a battery temperature control device.

BACKGROUND ART Conventionally, a battery temperature control device that controls the temperature of a plurality of batteries using a refrigeration cycle is known, for example, from Patent Document 1. The refrigeration cycle includes a compressor, an external fluid heat exchanger, an expansion valve, and a plurality of battery heat exchangers. The compressor compresses and discharges the refrigerant. The external fluid heat exchanger exchanges heat between an external fluid and a refrigerant. The expansion valve reduces the pressure of the refrigerant. The plurality of battery heat exchangers are arranged corresponding to each of the plurality of batteries. Each battery heat exchanger exchanges heat between each battery and the refrigerant. Thereby, each battery is adjusted to a predetermined set temperature.

JP2020-167131A

In such a battery temperature control device, the refrigeration cycle can be switched between a battery cooling mode in which each battery is cooled and a battery warm-up mode in which each battery is warmed up. In this way, the battery temperature control device can adjust each battery to a predetermined set temperature by cooling each battery, or adjust each battery to a predetermined set temperature by warming up each battery. I do things. However, there is a problem in that the temperature of each battery varies.

The battery temperature control device that solves the above problems consists of a compressor that compresses and discharges refrigerant, an external fluid heat exchanger that exchanges heat between the external fluid and the refrigerant, an expansion valve that reduces the pressure of the refrigerant, and multiple batteries. A refrigeration cycle includes a plurality of battery heat exchangers arranged correspondingly to each other and exchanging heat between each of the batteries and a refrigerant, each of the battery heat exchangers having a first port and a second port. ports, and the refrigeration cycle has a plurality of first individual flow paths each connected to each of the first ports, and a connection between the plurality of first individual flow paths and the external fluid heat exchanger. a plurality of second individual flow paths connected to each of the second ports, and a second main flow path connecting the plurality of second individual flow paths and the compressor. Each of the first individual channels is provided with the expansion valve, and the refrigeration cycle has a battery cooling mode for cooling each battery, and a battery warming mode for warming up each battery. , and in the battery cooling mode, the refrigerant discharged from the compressor radiates heat to the external fluid in the external fluid heat exchanger, and flows through the first main flow path to cool each of the first Each of the battery heat exchangers is distributed into individual flow paths, is depressurized by each of the expansion valves, and flows inside each of the battery heat exchangers via the first port of each of the battery heat exchangers. absorbs heat from each of the batteries, is discharged to each of the second individual flow paths through the second port of each of the battery heat exchangers, joins the second main flow path, and is returned to the compressor; In the battery warm-up mode, the refrigerant discharged from the compressor flows through the second main flow path and is distributed to each of the second individual flow paths, and through the second port of each of the battery heat exchangers. By flowing inside each of the battery heat exchangers, heat is radiated to each of the batteries in each of the battery heat exchangers, and each of the first individual flow paths passes through the first port of each of the battery heat exchangers. The fluid is discharged to the external fluid heat exchanger, is depressurized by each of the expansion valves, merges into the first main flow path, and is supplied to the external fluid heat exchanger, thereby absorbing heat from the external fluid in the external fluid heat exchanger; In the battery temperature control device, the refrigeration cycle further includes a refrigerant heat exchanger that exchanges heat between the refrigerant flowing through the first main flow path and the refrigerant flowing through the second main flow path. .

For example, in the battery cooling mode, the refrigerant flowing through the first main channel is cooled by the refrigerant flowing through the second main channel via the refrigerant heat exchanger. Therefore, the refrigerant flowing through the first main channel after being heat radiated by the external fluid heat exchanger can be sufficiently liquefied before being depressurized by each expansion valve. Therefore, since the liquefied refrigerant can be distributed from the first main flow path to each of the first individual flow paths, the liquefied refrigerant can be easily distributed evenly to each battery heat exchanger. As a result, variations in temperature of each battery can be suppressed.

For example, in the battery warm-up mode, the refrigerant flowing through the second main channel is cooled by the refrigerant flowing through the first main channel via the refrigerant heat exchanger. Thereby, the refrigerant flowing through the second main flow path can be a gas-liquid two-phase refrigerant. Therefore, the refrigerant in a gas-liquid two-phase state can be distributed from the second main channel to each second individual flow path, so that the refrigerant in a gas-liquid two-phase state can be distributed to each battery heat exchanger. be able to. In the gas-liquid two-phase state, the temperature of the refrigerant is isothermal, so the temperature of the refrigerant is constant. Therefore, since the temperature difference between the refrigerant flowing in each battery heat exchanger and each battery is maintained, it is possible to warm up each battery uniformly as a whole. As a result, variations in temperature of each battery can be suppressed.

In the battery temperature control device, the plurality of battery heat exchangers are arranged side by side in one direction, and the first main flow path extends in the direction in which the plurality of battery heat exchangers are arranged in parallel, and the first main flow path extends in the direction in which the plurality of battery heat exchangers are arranged in parallel. the second main flow path extends in the direction in which the plurality of battery heat exchangers are arranged in parallel, and the second main flow path is connected to each of the second individual flow paths. The refrigerant heat exchanger has a second elongated flow path, and the refrigerant heat exchanger is configured to exchange heat between the refrigerant flowing through the first elongated flow path and the refrigerant flowing through the second elongated flow path. Good.

The first extended flow path is a portion of the first main flow path to which each of the first individual flow paths is connected, and therefore a portion of the first main flow path that necessarily extends in the direction in which the plurality of battery heat exchangers are arranged in parallel. It is. The second extended flow path is a portion of the second main flow path to which each of the second individual flow paths is connected, and therefore a portion of the second main flow path that necessarily extends in the direction in which the plurality of battery heat exchangers are arranged side by side. It is. Therefore, heat exchange between the refrigerant flowing through the first extended flow path and the refrigerant flowing through the second extended flow path was made possible via a refrigerant heat exchanger. According to this, while making effective use of space, it is possible to efficiently exchange heat between the refrigerant flowing in the first main flow path and the refrigerant flowing in the second main flow path.

In the battery temperature control device, the refrigeration cycle includes an extended pipe in which the first extended flow path and the second extended flow path are formed, and the extended pipe includes the first extended flow path. and the second extending flow path, and the partition wall is configured to perform heat exchange between the refrigerant flowing in the first extending flow path and the refrigerant flowing in the second extending flow path. Preferably, it is a refrigerant heat exchanger.

According to this, it is possible to have a more compact configuration than, for example, when the piping forming the first extending flow path and the piping forming the second extending flow path are separate members. Since the refrigerant flowing in the first extended flow path and the refrigerant flowing in the second extended flow path can exchange heat through the partition wall of the extended pipe, the refrigerant flowing in the first extended flow path and the refrigerant flowing in the second extended flow path can exchange heat. Heat exchange with the refrigerant flowing through the second extended flow path can be easily performed.

In the battery temperature control device, the plurality of battery heat exchangers are arranged side by side in one direction, and the first main flow path extends in the direction in which the plurality of battery heat exchangers are arranged in parallel, and the first main flow path extends in the direction in which the plurality of battery heat exchangers are arranged in parallel. a first extending flow path to which one individual flow path is connected; and a first connection flow path connecting the first extending flow path and the external fluid heat exchanger; connects a second extending flow path that extends in the direction in which the plurality of battery heat exchangers are arranged in parallel and to which each of the second individual flow paths is connected, and the second extended flow path and the compressor; a second connection flow path, and the refrigerant heat exchanger is configured to exchange heat between the refrigerant flowing through the first connection flow path and the refrigerant flowing through the second connection flow path. good.

For example, consider a case where there is a restriction on the space between the first extending channel and the second extending channel. Even in this case, by enabling heat exchange between the refrigerant flowing through the first connection flow path and the refrigerant flowing through the second connection flow path, the refrigerant flowing through the first main flow path and the refrigerant flowing through the second connection flow path can be exchanged with each other through the refrigerant heat exchanger. Heat exchange can be performed with the refrigerant flowing through the two main channels.

According to this invention, variations in temperature of each battery can be suppressed.

FIG. 1 is a diagram schematically showing the overall configuration of a battery temperature control device in an embodiment. FIG. 3 is an enlarged cross-sectional view of a part of the battery temperature control device. It is a Mollier diagram showing the relationship between specific enthalpy and pressure of a refrigerant in a comparative example. It is a Mollier diagram showing the relationship between specific enthalpy and pressure of a refrigerant in an embodiment. It is a Mollier diagram showing the relationship between specific enthalpy and pressure of a refrigerant in a comparative example. It is a Mollier diagram showing the relationship between specific enthalpy and pressure of a refrigerant in an embodiment. It is a figure which shows typically the whole structure of the battery temperature control apparatus in another embodiment. It is a figure which shows typically the whole structure of the battery temperature control apparatus in another embodiment.

An embodiment of a battery temperature control device will be described below with reference to FIGS. 1 to 6. The battery temperature control device of this embodiment is mounted on a vehicle, for example.
<Overall configuration of battery temperature control device 10>
As shown in FIG. 1, the battery temperature control device 10 includes a refrigeration cycle 11. The battery temperature control device 10 uses the refrigeration cycle 11 to cool and warm up the plurality of batteries 20 . The battery 20 has a plurality of square batteries 20a that are battery cells. The battery 20 is configured by arranging the prismatic batteries 20a in parallel with each other with the thickness directions of the prismatic batteries 20a being the same. Each square battery 20a is, for example, a lithium ion battery or a nickel metal hydride battery. The plurality of batteries 20 are arranged side by side in a direction perpendicular to the direction in which the plurality of square batteries 20a are arranged side by side. The plurality of batteries 20 are packaged as one battery pack, for example, by being housed in a housing (not shown).

The refrigeration cycle 11 includes a compressor 12 , an external fluid heat exchanger 13 , a plurality of expansion valves 14 , and a plurality of battery heat exchangers 15 . The compressor 12 compresses low-temperature, low-pressure refrigerant and discharges high-temperature, high-pressure refrigerant. The external fluid heat exchanger 13 exchanges heat between outside air, which is an external fluid, and a refrigerant. Each expansion valve 14 reduces the pressure of the refrigerant. The plurality of battery heat exchangers 15 are arranged corresponding to the plurality of batteries 20, respectively. Therefore, the plurality of battery heat exchangers 15 are arranged side by side in the same direction as the direction in which the plurality of batteries 20 are arranged side by side. Therefore, the plurality of battery heat exchangers 15 are arranged side by side in one direction. Each battery heat exchanger 15 exchanges heat between each battery 20 and a refrigerant. Note that the refrigeration cycle 11 has an accumulator (not shown). The accumulator allows gaseous refrigerant to flow into the compressor 12 and prevents liquid refrigerant from flowing into the compressor 12 .

<Configuration of battery heat exchanger 15>
Each battery heat exchanger 15 includes a first header 31 , a first tube 32 , an intermediate header 33 , a second tube 34 , and a second header 35 . The first header 31 has a first port 41 . The second header 35 has a second port 42 . Therefore, each battery heat exchanger 15 has a first port 41 and a second port 42, respectively.

The first tube 32 and the second tube 34 are arranged side by side in the direction in which the plurality of battery heat exchangers 15 are arranged side by side. The first tube 32 and the second tube 34 extend parallel to each other. The first tube 32 and the second tube 34 exchange heat with the battery 20. A first end of the first tube 32 communicates with the inside of the first header 31 . The second end of the first tube 32 communicates with the interior of the intermediate header 33. A first end of the second tube 34 communicates with the inside of the second header 35 . The second end of the second tube 34 communicates with the inside of the intermediate header 33 . The intermediate header 33 connects the second end of the first tube 32 and the second end of the second tube 34.

<Detailed configuration of refrigeration cycle 11>
The refrigeration cycle 11 includes a plurality of first individual channels 51, a first main channel 52, a plurality of second individual channels 61, and a second main channel 62. The plurality of first individual channels 51 are connected to each first port 41, respectively. Each first individual flow path 51 is provided with an expansion valve 14, respectively. The plurality of second individual channels 61 are connected to each second port 42, respectively.

The first main flow path 52 has a first extending flow path 53 and a first connection flow path 54 . The first extending channel 53 extends in the direction in which the plurality of battery heat exchangers 15 are arranged side by side. Each first individual flow path 51 is connected to the first extended flow path 53 . The first connecting channel 54 connects the first extending channel 53 and the external fluid heat exchanger 13 . Therefore, the first main flow path 52 connects the plurality of first individual flow paths 51 and the external fluid heat exchanger 13.

The second main flow path 62 has a second extending flow path 63 and a second connection flow path 64 . The second extending flow path 63 extends in the direction in which the plurality of battery heat exchangers 15 are arranged side by side. Each second individual flow path 61 is connected to the second extended flow path 63 . The second connecting channel 64 connects the second extending channel 63 and the compressor 12 . Therefore, the second main flow path 62 connects the plurality of second individual flow paths 61 and the compressor 12.

<Extended piping 70>
As shown in FIG. 2, the refrigeration cycle 11 includes an extended pipe 70. The extended pipe 70 includes a pipe main body 71, a plurality of first pipes 72, and a plurality of second pipes 73. The pipe main body 71 is a pipe that extends linearly. The extending pipe 70 is arranged with respect to the plurality of battery heat exchangers 15 such that the extending direction of the pipe body 71 is the same direction as the direction in which the plurality of battery heat exchangers 15 are arranged side by side.

A first extending channel 53 and a second extending channel 63 are formed in the piping body 71 . Therefore, the first extending channel 53 and the second extending channel 63 are formed in the extending pipe 70 . The first extending channel 53 and the second extending channel 63 extend parallel to each other inside the extending pipe 70. The first extending channel 53 and the second extending channel 63 are partitioned off inside the extending pipe 70 by a partition wall 74 that is a part of the extending pipe 70. Therefore, the extending pipe 70 has a partition wall 74 that partitions the first extending flow path 53 and the second extending flow path 63.

The partition wall 74 performs heat exchange between the first extending channel 53 and the second extending channel 63. The refrigerant flowing through the first extended flow path 53 and the refrigerant flowing through the second extended flow path 63 can exchange heat via the partition wall 74. Therefore, the partition wall 74 is a refrigerant heat exchanger that performs heat exchange between the refrigerant flowing through the first extended flow path 53 and the refrigerant flowing through the second extended flow path 63. Therefore, the refrigeration cycle 11 further includes a refrigerant heat exchanger that exchanges heat between the refrigerant flowing in the first main flow path 52 and the refrigerant flowing in the second main flow path 62. The refrigerant heat exchanger is configured to exchange heat between the refrigerant flowing through the first extended flow path 53 and the refrigerant flowing through the second extended flow path 63.

The plurality of first pipes 72 are connected to the pipe main body 71. The plurality of first pipes 72 are arranged at equal intervals in the extending direction of the pipe main body 71. The inside of each first pipe 72 is connected to the first extending channel 53 . The inside of each first pipe 72 is the first individual flow path 51 . Each first pipe 72 is provided with an expansion valve 14 . Each first pipe 72 is connected to the first port 41 of the first header 31 of each battery heat exchanger 15.

The plurality of second pipes 73 are connected to the pipe main body 71. The plurality of second pipes 73 are arranged at regular intervals in the extending direction of the pipe main body 71. The inside of each second pipe 73 is connected to the second extending flow path 63 . The inside of each second pipe 73 is a second individual flow path 61 . Each second pipe 73 is connected to the second port 42 of the second header 35 of each battery heat exchanger 15. Note that the first extending channel 53 is connected to piping forming the first connecting channel 54, and the second extending channel 63 is connected to piping forming the second connecting channel 64. There is.

<Control unit 16>
As shown in FIG. 1, the battery temperature control device 10 includes a control section 16. The control unit 16 switches the refrigeration cycle 11 to a battery cooling mode in which each battery 20 is cooled and a battery warm-up mode in which each battery 20 is warmed up. Therefore, the refrigeration cycle 11 can be switched between a battery cooling mode in which each battery 20 is cooled and a battery warm-up mode in which each battery 20 is warmed up.

The refrigeration cycle 11 includes a four-way valve 17. The four-way valve 17 is a solenoid valve. The four-way valve 17 is electrically connected to the control section 16. The four-way valve 17 receives a control signal from the control section 16. The four-way valve 17 can be switched between a first switching state and a second switching state based on a control signal from the control unit 16. The four-way valve 17 is switched to the first switching state by the control unit 16 in the battery cooling mode. The four-way valve 17 is switched to the second switching state by the control unit 16 in the battery warm-up mode.

When the four-way valve 17 enters the first switching state, it causes the refrigerant discharged from the compressor 12 to flow toward the external fluid heat exchanger 13, as shown by arrow R1 in FIG. On the other hand, when the four-way valve 17 enters the second switching state, it causes the refrigerant discharged from the compressor 12 to flow toward the second header 35 of each battery heat exchanger 15, as shown by arrow R2 in FIG.

<Battery cooling mode>
In the battery cooling mode, the refrigerant discharged from the compressor 12 radiates heat to the outside air in the external fluid heat exchanger 13. The refrigerant that has radiated heat to the outside air in the external fluid heat exchanger 13 flows through the first main flow path 52 and is distributed to each of the first individual flow paths 51 . The refrigerant distributed to each first individual flow path 51 is depressurized by each expansion valve 14 . The refrigerant whose pressure has been reduced by each expansion valve 14 flows inside each battery heat exchanger 15 via the first port 41 of each battery heat exchanger 15 . The refrigerant flowing through each battery heat exchanger 15 absorbs heat from each battery 20 in each battery heat exchanger 15 . The refrigerant that has absorbed heat from each battery 20 in each battery heat exchanger 15 is discharged to each second individual flow path 61 via the second port 42 of each battery heat exchanger 15 . The refrigerant discharged into each second individual flow path 61 joins the second main flow path 62 and is returned to the compressor 12.

<Battery warm-up mode>
In the battery warm-up mode, the refrigerant discharged from the compressor 12 flows through the second main flow path 62 and is distributed to each second individual flow path 61 . The refrigerant distributed to each second individual flow path 61 flows inside each battery heat exchanger 15 via the second port 42 of each battery heat exchanger 15 . The refrigerant flows inside each battery heat exchanger 15 and radiates heat to each battery 20 in each battery heat exchanger 15 . The refrigerant that has radiated heat to each battery 20 in each battery heat exchanger 15 is discharged to each first individual flow path 51 via the first port 41 of each battery heat exchanger 15 . The refrigerant discharged to each first individual flow path 51 is depressurized by each expansion valve 14 . The refrigerant whose pressure has been reduced by each expansion valve 14 joins the first main flow path 52 and is supplied to the external fluid heat exchanger 13 . The refrigerant is supplied to the external fluid heat exchanger 13, absorbs heat from the outside air in the external fluid heat exchanger 13, and is returned to the compressor 12.

[Operation of embodiment]
Next, the operation of this embodiment will be explained.
3, FIG. 4, FIG. 5, and FIG. 6 show Mollier diagrams representing the relationship between specific enthalpy and pressure of a refrigerant. 3, FIG. 4, FIG. 5, and FIG. 6, the horizontal axis is the specific enthalpy of the refrigerant, and the vertical axis is the pressure of the refrigerant. As shown in FIGS. 3, 4, 5, and 6, in a curve that extends upward, the curve drawn to the left of the critical point CP, which is the apex, is the saturated liquid line L1, and the critical point The curve drawn to the right of CP is the saturated steam line L2. The region surrounded by the saturated liquid line L1 and the saturated vapor line L2 is a two-phase region A1 in which the refrigerant is in a gas-liquid two-phase state. The region to the left of the saturated liquid line L1 is a liquid region A2 where the refrigerant is in a liquid state. The region to the right of the saturated vapor line L2 is a gas region A3 in which the refrigerant is in a gas state.

A solid line L10 shown in FIG. 3 indicates the refrigeration cycle 11 when the refrigerant flowing through the first main flow path 52 and the refrigerant flowing through the second main flow path 62 are not able to exchange heat via the partition wall 74 in the battery cooling mode. is shown as a comparative example. A state point a10 shown in FIG. 3 indicates the state of the refrigerant flowing through the first main flow path 52 after being radiated by the external fluid heat exchanger 13. State point a10 exists on the saturated liquid line L1. Therefore, in the battery cooling mode, if the refrigerant flowing through the first main flow path 52 and the refrigerant flowing through the second main flow path 62 are not able to exchange heat via the partition wall 74, the refrigerant flowing through the first main flow path 52 , a gas-liquid two-phase state.

A solid line L11 shown in FIG. 4 indicates the refrigeration cycle 11 when the refrigerant flowing through the first main flow path 52 and the refrigerant flowing through the second main flow path 62 can exchange heat via the partition wall 74 in the battery cooling mode. It shows the status of. A state point a11 shown in FIG. 4 indicates the state of the refrigerant flowing through the first main flow path 52 after being radiated by the external fluid heat exchanger 13. State point a11 exists in liquid area A2.

In the battery cooling mode, the refrigerant flowing through the first main flow path 52 is cooled by the refrigerant flowing through the second main flow path 62 via the partition wall 74 . Therefore, the refrigerant that has been heat radiated by the external fluid heat exchanger 13 and flows through the first main flow path 52 is sufficiently liquefied before being depressurized by each expansion valve 14, and is therefore in a liquid state. Therefore, the liquefied refrigerant is distributed from the first main flow path 52 to each of the first individual flow paths 51, so that the liquefied refrigerant is easily distributed to each battery heat exchanger 15 evenly. As a result, variations in temperature of each battery 20 are suppressed.

A solid line L20 shown in FIG. 5 indicates a refrigeration cycle when the refrigerant flowing through the first main flow path 52 and the refrigerant flowing through the second main flow path 62 are not able to exchange heat via the partition wall 74 in the battery warm-up mode. Condition No. 11 is shown as a comparative example. As shown in FIG. 5, the refrigerant discharged from the compressor 12 flows into each battery heat exchanger 15 in a gas state. The refrigerant flows inside each battery heat exchanger 15 and radiates heat to each battery 20 in each battery heat exchanger 15 . As a result, the refrigerant flowing inside each battery heat exchanger 15 enters a gas-liquid two-phase state midway inside each battery heat exchanger 15.

A solid line L21 shown in FIG. 6 indicates a refrigeration cycle when heat exchange is possible between the refrigerant flowing through the first main flow path 52 and the refrigerant flowing through the second main flow path 62 via the partition wall 74 in the battery warm-up mode. 11 states are shown. As shown in FIG. 6, the refrigerant discharged from the compressor 12 flows into each battery heat exchanger 15 in a gas-liquid two-phase state.

In the battery warm-up mode, the refrigerant flowing through the second main flow path 62 is cooled by the refrigerant flowing through the first main flow path 52 via the partition wall 74 . As a result, the refrigerant flowing through the second main flow path 62 is in a gas-liquid two-phase state. Therefore, since the refrigerant in a gas-liquid two-phase state is distributed from the second main flow path 62 to each second individual flow path 61, the refrigerant in a gas-liquid two-phase state is distributed to each battery heat exchanger 15. be done. In the gas-liquid two-phase state, the temperature of the refrigerant is isothermal, so the temperature of the refrigerant is constant. Therefore, since the temperature difference between the refrigerant flowing in each battery heat exchanger 15 and each battery 20 is maintained, each battery 20 is warmed up uniformly as a whole. As a result, variations in temperature of each battery 20 are suppressed.

[Effects of embodiment]
In the above embodiment, the following effects can be obtained.
(1) The refrigeration cycle 11 further includes a partition wall 74 that performs heat exchange between the refrigerant flowing in the first main flow path 52 and the refrigerant flowing in the second main flow path 62.

For example, in the battery cooling mode, the refrigerant flowing through the first main flow path 52 is cooled by the refrigerant flowing through the second main flow path 62 via the partition wall 74 . Therefore, the refrigerant that is heat radiated in the external fluid heat exchanger 13 and flows through the first main flow path 52 can be brought into a liquid state by sufficiently liquefying the refrigerant before being depressurized by each expansion valve 14 . Therefore, since the liquefied refrigerant can be distributed from the first main flow path 52 to each of the first individual flow paths 51, the liquefied refrigerant can be easily distributed to each battery heat exchanger 15 evenly. As a result, variations in temperature of each battery 20 can be suppressed.

For example, in the battery warm-up mode, the refrigerant flowing through the second main flow path 62 is cooled by the refrigerant flowing through the first main flow path 52 via the partition wall 74 . Thereby, the refrigerant flowing through the second main flow path 62 can be a gas-liquid two-phase refrigerant. Therefore, since the refrigerant in a gas-liquid two-phase state can be distributed from the second main flow path 62 to each of the second individual flow paths 61, the refrigerant in a gas-liquid two-phase state can be distributed to each battery heat exchanger 15. can be distributed to. In the gas-liquid two-phase state, the temperature of the refrigerant is isothermal, so the temperature of the refrigerant is constant. Therefore, the temperature difference between the refrigerant flowing in each battery heat exchanger 15 and each battery 20 is maintained, so that each battery 20 can be warmed up uniformly as a whole. As a result, variations in temperature of each battery 20 can be suppressed.

(2) Since the first extended flow path 53 is a portion to which each of the first individual flow paths 51 in the first main flow path 52 is connected, in the first main flow path 52, a plurality of battery heat exchangers 15 are arranged in parallel. This is the part that necessarily extends in the direction of installation. Since the second extended flow path 63 is a portion to which each of the second individual flow paths 61 in the second main flow path 62 is connected, in the second main flow path 62, the second extended flow path 63 is a portion in which the plurality of battery heat exchangers 15 are arranged in parallel. It is a part that inevitably extends. Therefore, heat exchange between the refrigerant flowing through the first extended flow path 53 and the refrigerant flowing through the second extended flow path 63 was made possible via the partition wall 74. According to this, it is possible to efficiently exchange heat between the refrigerant flowing through the first main flow path 52 and the refrigerant flowing through the second main flow path 62 while making effective use of space.

(3) The refrigeration cycle 11 includes an extended pipe 70 in which a first extended flow path 53 and a second extended flow path 63 are formed. The extending pipe 70 has a partition wall 74 that partitions the first extending flow path 53 and the second extending flow path 63. The partition wall 74 is a refrigerant heat exchanger that exchanges heat between the refrigerant flowing through the first extended flow path 53 and the refrigerant flowing through the second extended flow path 63 . According to this, for example, the configuration can be made more compact than when the piping forming the first extending flow path 53 and the piping forming the second extending flow path 63 are each separate members. can. Since the refrigerant flowing through the first extended flow path 53 and the refrigerant flowing through the second extended flow path 63 can exchange heat via the partition wall 74 of the extended pipe 70, the first extended flow path Heat exchange between the refrigerant flowing through the refrigerant 53 and the refrigerant flowing through the second extended flow path 63 can be easily performed.

[Example of change]
Note that the above embodiment can be modified and implemented as follows. The above embodiment and the following modification examples can be implemented in combination with each other within a technically consistent range.

○ As shown in FIG. 7, the refrigeration cycle 11 does not need to include the extension pipe 70. The refrigeration cycle 11 may include a refrigerant heat exchanger 80 that exchanges heat between the refrigerant flowing through the first main flow path 52 and the refrigerant flowing through the second main flow path 62, separately from the extension pipe 70.

○ As shown in FIG. 8, the refrigeration cycle 11 does not need to include the extension pipe 70. The refrigeration cycle 11 may include, for example, a refrigerant heat exchanger 81 configured to exchange heat between the refrigerant flowing through the first connection flow path 54 and the refrigerant flowing through the second connection flow path 64. . In such a case, for example, the piping forming the first connecting flow path 54 and the piping forming the second connecting flow path 64 may be configured as double piping, so that the two pipings can avoid heat from each other. It is replaceable. For example, consider a case where there is a restriction on the space between the first extending channel 53 and the second extending channel 63. Even in this case, by enabling heat exchange between the refrigerant flowing through the first connection flow path 54 and the refrigerant flowing through the second connection flow path 64 via the refrigerant heat exchanger 81, the first main flow path 52 can be Heat exchange can be performed between the flowing refrigerant and the refrigerant flowing through the second main flow path 62.

In the embodiment, each battery heat exchanger 15 has a configuration including a first header 31, a first tube 32, an intermediate header 33, a second tube 34, and a second header 35. However, it is not limited to this. Each battery heat exchanger 15 only needs to have a first port 41 and a second port 42, respectively. The specific configuration of the plurality of battery heat exchangers 15 is not particularly limited as long as it is arranged corresponding to each of the plurality of batteries 20 and can exchange heat between each battery 20 and the refrigerant. It is not something that will be done.

In the embodiment, the number of battery heat exchangers 15 is not particularly limited. The number of battery heat exchangers 15 is changed as appropriate depending on the number of batteries 20.
In the embodiment, the external fluid heat exchanger 13 may be configured to be capable of exchanging heat between cooling water, which is an external fluid, and a refrigerant, for example.

DESCRIPTION OF SYMBOLS 10... Battery temperature control device, 11... Refrigeration cycle, 12... Compressor, 13... External fluid heat exchanger, 14... Expansion valve, 15... Battery heat exchanger, 20... Battery, 41... First port, 42... First port 2 ports, 51...first individual flow path, 52...first main flow path, 53...first extending flow path, 54...first connection flow path, 61...second individual flow path, 62...second main flow path, 63... Second extending channel, 64... Second connecting channel, 70... Extending pipe, 74... Partition wall which is a refrigerant heat exchanger, 80, 81... Refrigerant heat exchanger.

Claims (4)

a compressor that compresses and discharges refrigerant;
an external fluid heat exchanger that exchanges heat between an external fluid and a refrigerant;
an expansion valve that reduces the pressure of the refrigerant;
A refrigeration cycle including a plurality of battery heat exchangers arranged corresponding to each of the plurality of batteries and exchanging heat between each of the batteries and a refrigerant,
Each of the battery heat exchangers has a first port and a second port,
The refrigeration cycle is
a plurality of first individual channels respectively connected to each of the first ports;
a first main flow path connecting the plurality of first individual flow paths and the external fluid heat exchanger;
a plurality of second individual channels respectively connected to each of the second ports;
a second main flow path connecting the plurality of second individual flow paths and the compressor;
Each of the first individual channels is provided with the expansion valve,
The refrigeration cycle is switchable between a battery cooling mode in which each battery is cooled and a battery warm-up mode in which each battery is warmed up,
In the battery cooling mode, the refrigerant discharged from the compressor radiates heat to the external fluid in the external fluid heat exchanger, flows through the first main flow path, and is distributed to each of the first individual flow paths, The pressure is reduced by each of the expansion valves, and the heat is absorbed from each battery by each battery heat exchanger by flowing through the inside of each battery heat exchanger through the first port of each battery heat exchanger. and is discharged to each of the second individual channels through the second port of each of the battery heat exchangers, joins the second main channel, and is returned to the compressor;
In the battery warm-up mode, the refrigerant discharged from the compressor flows through the second main flow path and is distributed to each of the second individual flow paths, and through the second port of each of the battery heat exchangers. By flowing inside each of the battery heat exchangers, heat is radiated to each of the batteries in each of the battery heat exchangers, and each of the first individual flow paths passes through the first port of each of the battery heat exchangers. The fluid is discharged to the external fluid heat exchanger, is depressurized by each of the expansion valves, merges into the first main flow path, and is supplied to the external fluid heat exchanger, thereby absorbing heat from the external fluid in the external fluid heat exchanger; A battery temperature control device in which the flow is returned to the compressor,
The battery temperature control device is characterized in that the refrigeration cycle further includes a refrigerant heat exchanger that exchanges heat between the refrigerant flowing in the first main flow path and the refrigerant flowing in the second main flow path. The plurality of battery heat exchangers are arranged in one direction,
The first main flow path has a first extending flow path that extends in the direction in which the plurality of battery heat exchangers are arranged side by side and to which each of the first individual flow paths is connected,
The second main flow path has a second extending flow path that extends in the direction in which the plurality of battery heat exchangers are arranged side by side and to which each of the second individual flow paths is connected,
The refrigerant heat exchanger is configured to perform heat exchange between the refrigerant flowing through the first extended flow path and the refrigerant flowing through the second extended flow path. battery temperature control device. The refrigeration cycle includes an extended pipe in which the first extended flow path and the second extended flow path are formed,
The extending pipe has a partition wall that partitions the first extending channel and the second extending channel,
3. The partition wall is the refrigerant heat exchanger that exchanges heat between the refrigerant flowing through the first extended flow path and the refrigerant flowing through the second extended flow path. Battery temperature control device. The plurality of battery heat exchangers are arranged in one direction,
The first main flow path is
a first extending channel extending in the direction in which the plurality of battery heat exchangers are arranged side by side and to which each of the first individual channels is connected;
a first connection flow path connecting the first extended flow path and the external fluid heat exchanger;
The second main flow path is
a second extending flow path extending in the direction in which the plurality of battery heat exchangers are arranged side by side and to which each of the second individual flow paths is connected;
a second connecting flow path connecting the second extending flow path and the compressor;
The battery according to claim 1, wherein the refrigerant heat exchanger is configured to exchange heat between the refrigerant flowing through the first connection flow path and the refrigerant flowing through the second connection flow path. Temperature control device.

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