CN111554851B - Battery pack and heat dissipation method thereof - Google Patents

Abstract

A battery pack includes a casing, a cell and a BMS arranged in the casing, and the BMS is electrically connected to the cell. The battery pack also includes a first heat sink disposed inside the casing, a second heat sink disposed outside the casing, and a semiconductor cooling fin positioned between the first heat sink and the second heat sink , the semiconductive cooling sheet includes a first end connected to the first heat sink and a second end connected to the second heat sink. The BMS is also electrically connected to the semiconductor cooling chip, and the BMS is used to control the cooling of the semiconductor cooling chip at the first end and heating at the second end, respectively. The present application also provides a heat dissipation method for the above-mentioned battery pack.

Description

Battery pack and cooling method thereof

technical field

The present application relates to the field of batteries, in particular to a battery pack and a heat dissipation method thereof.

Background technique

At present, with the rapid development of the new energy industry, battery applications are more extensive, such as providing electric energy for electric vehicles through power battery systems, which can reduce the use of non-renewable resources.

During the use of the battery, the electrical components on the battery management system (Battery Management System, BMS) will consume part of the power and convert it into heat. If the heat dissipation is not good, it will easily lead to continuous heat accumulation inside the electrical components. Heat buildup continues inside electrical components. Especially for high-power electrical devices such as pre-charging resistors, relays, and MOS tubes, a large amount of heat may be generated under extreme working conditions (such as switching relays multiple times in a short period of time in a high-temperature environment, pre-charging resistors lead to instantaneous temperature rise), if effective cooling measures cannot be taken to dissipate this part of the heat in time, the temperature inside the electrical device will rise rapidly, even exceeding the normal operating temperature of the electrical device. In this way, the aging of the electrical device will be accelerated and its service life will be reduced.

Contents of the invention

In order to solve the above deficiencies in the prior art, it is necessary to provide a battery pack capable of effectively dissipating heat from the BMS, thereby improving the service life of the BMS.

In addition, it is also necessary to provide a heat dissipation method for the battery pack.

The present application provides a battery pack, including a casing, a battery cell and a BMS arranged in the casing, and the BMS is electrically connected to the battery cell. The battery pack also includes a first radiator arranged inside the casing, a second radiator arranged outside the casing, and a semiconductor cooling sheet between the first radiator and the second radiator, and the semiconductor cooling sheet includes a radiator connected to the first radiator. The first end and the second end connected to the second heat sink. The BMS is also electrically connected to the semiconductor cooling chip, and the BMS is used to control the cooling of the semiconductor cooling chip at the first end and heating at the second end.

In this application, the BMS controls the semiconductor refrigeration chip to perform cooling and heating at the first end and the second end respectively, thereby forming a cold end and a hot end. In this way, the cold energy generated by the semiconductor refrigeration sheet at the cold end can be transmitted to the BMS through the first radiator, and the temperature of the cold energy at the cold end can be lower than the ambient temperature, so even if the electronic components of the BMS are under extreme working conditions, they can be cooled quickly. The electronic components are cooled to avoid the problem that the heat dissipation effect of the electronic components is not high when only relying on the first radiator to dissipate heat, realize the thermal management of the BMS under extreme working conditions, and prolong the service life of the BMS.

In at least one embodiment of the present application, when the temperature value of the BMS is greater than or equal to a preset value, the BMS is also used to control the conduction between the battery cell and the semiconductor cooling chip.

In at least one embodiment of the present application, a first phase-change material layer is provided between the semiconductive cooling sheet and the first heat sink. When heat is conducted to the first phase-change material layer, the heat-conducting phase-change material in the first phase-change material layer absorbs latent heat and changes from solid to liquid, thereby quickly dissipating heat on the electronic components.

In at least one embodiment of the present application, a second phase change material layer is provided between the semiconductive cooling sheet and the second heat sink. When heat is conducted to the second phase-change material layer, the heat-conducting phase-change material in the second phase-change material layer absorbs latent heat and changes from a solid state to a liquid state, thereby quickly dissipating the heat of the semiconductor cooling chip.

In at least one embodiment of the present application, the first heat sink includes a first base and a first cooling fin located on the first base, the first base is also provided with a first accommodation groove, and the first end is located in the slot.

In at least one embodiment of the present application, the second heat sink includes a second base and a second cooling fin on the second base, the second base is also provided with a second accommodation groove, and the second end is located in the second accommodation in the slot. The semiconductor cooling chip can be positioned in the first accommodating groove and the second accommodating groove.

In at least one embodiment of the present application, a thermally conductive material is disposed between the first end and the first accommodating groove.

In at least one embodiment of the present application, a thermally conductive material is disposed between the second end and the second accommodating groove. The heat conduction material is used to improve the heat conduction efficiency between the semiconductive cooling sheet and the first radiator and the heat conduction efficiency between the semiconductive cooling sheet and the second radiator.

The present application also provides a heat dissipation method for the battery pack as before, including the following steps: the BMS controls the semiconductor refrigeration sheet to cool at the first end and heat at the second end; the first end conducts the cold energy to the first radiator and BMS, the second end conducts the heat to the second heat sink.

In at least one embodiment of the present application, the BMS controls the semiconductor cooling fins to cool at the first end and heat at the second end respectively, and the heat dissipation method further includes: when the temperature value of the BMS is greater than or equal to a preset value, the BMS controls the electric The conduction between the core and the semiconductor cooling chip.

In at least one embodiment of the present application, the heat dissipation method further includes: when the temperature of the BMS drops below a preset value, the BMS stops conducting the electric core and the semiconductor cooling chip.

In at least one embodiment of the present application, the heat dissipation method further includes: the BMS conducts heat to the first radiator.

Description of drawings

FIG. 1 is a schematic structural diagram of a battery pack according to an embodiment of the present application.

FIG. 2 is a front view of the battery pack shown in FIG. 1 without the casing and batteries.

FIG. 3 is an exploded view of the battery pack shown in FIG. 1 without the shell and the battery cells.

FIG. 4 is a schematic diagram of the electrical connection of the battery cell, BMS and semiconductor cooling sheet in the battery pack shown in FIG. 1 .

FIG. 5A is a schematic structural view of the peltier shown in FIG. 3 .

FIG. 5B is a structural schematic diagram of another angle of the peltier shown in FIG. 3 .

FIG. 6 is a schematic structural diagram of the first radiator shown in FIG. 3 .

FIG. 7 is a structural schematic diagram of another angle of the second heat sink shown in FIG. 3 .

Description of main component symbols

shell 10

Cell 20

BMS 30

circuit board 31

Electronic components 32

First Radiator 40

first base 41

First heat sink 42

2nd radiator 50

Second base 51

Second heat sink 52

Peltier cooler 60

first end 61

second end 62

first terminal 63

Second terminal 64

first phase change material layer 70

second phase change material layer 80

battery pack 100

The first holding tank 410

Second holding tank 510

The following specific embodiments will further illustrate the present application in conjunction with the above-mentioned drawings.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Apparently, the described embodiments are only some of the embodiments of the application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used herein in the specification of the application are only for the purpose of describing specific embodiments, and are not intended to limit the application.

Some implementations of the present application will be described in detail below in conjunction with the accompanying drawings. In the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.

Referring to FIG. 1 to FIG. 4 , an embodiment of the present application provides a battery pack 100 , including a casing 10 and a battery cell 20 and a BMS 30 disposed in the casing 10 . The BMS 30 is electrically connected to the battery cell 20 . Wherein, the BMS 30 may include a circuit board 31 and electronic components 32 disposed on the circuit board 31 . The electronic component 32 can be, but not limited to, a pre-charging resistor, a relay, a MOS tube and the like. When the BMS 30 is working, the electronic component 32 will generate a certain amount of heat, especially under extreme working conditions (such as switching relays multiple times in a short period of time in a high temperature environment or the electronic component 32 is frequently subjected to thermal shock, etc.), the heat generated by the electronic component 32 Larger, causing internal electronic components 32 to accumulate heat.

The battery pack 100 also includes a first heat sink 40 disposed inside the housing 10 , a second heat sink 50 disposed outside the housing 10 , and a semiconductor cooling fin 60 located between the first heat sink 40 and the second heat sink 50 . The BMS 30 is also electrically connected to the semiconductor cooling chip 60 .

Please refer to FIG. 5A and FIG. 5B together. The semiconductor cooling fin 60 includes a first end 61 connected to the first heat sink 40 and a second end 62 connected to the second heat sink 50 . The BMS 30 is used to control the semiconductor cooling chip 60 to cool at the first end 61 and heat at the second end 62 respectively, thereby forming a cold end and a hot end. In at least one embodiment of the present application, when the temperature value of the electronic component 32 of the BMS 30 is greater than or equal to a preset value (for example, the electronic component 32 generates a lot of heat under extreme working conditions), the BMS 30 is also used to conduct The electric core 20 and the semiconductor cooling chip 60. Since the semiconductor cooling plate 60 includes a galvanic couple formed in series by two different types of semiconductor materials, using the Peltier effect of the semiconductor material, when the electric core 20 and the semiconductor cooling plate 60 conduct The refrigerating plate 60 supplies power, so that heat transfer occurs between the two ends of the galvanic couple, and the heat is transferred from one end to the other end. That is to say, the semiconductor cooling plate 60 can cool at the first end 61 and heat at the second end 62 respectively, thereby forming a cold end and a hot end.

In this way, on the one hand, the cold energy generated by the semiconductor cooling chip 60 at the cold end can be conducted to the BMS 30 through the first heat sink 40 , thereby cooling down the temperature of the electronic component 32 . Among them, the mode in which the cooling energy is conducted to the BMS 30 through the semiconductor cooling plate 60 to cool down the electronic components 32 is called an active heat dissipation mode. When the temperature of the electronic components 32 of the BMS 30 is greater than or equal to a preset value, the battery pack 100 can adopt an active heat dissipation mode to dissipate heat. On the other hand, the heat generated by the semiconductor cooling fin 60 and the hot end can be conducted to the second heat sink 50 and dissipated by the second heat sink 50 into the air of the external environment.

In addition, when the temperature value of the electronic component 32 of the BMS 30 is lower than the preset value, the battery cell 20 may stop supplying power to the peltier 60, and the peltier 60 does not work. At this time, the heat generated by the electronic components 32 is conducted to the first heat sink 40 and dissipated into the air inside the casing 10 by the first heat sink 40 . Wherein, the mode in which the electronic component 32 conducts heat to the first heat sink 40 to dissipate heat is a passive heat dissipation mode.

In this application, when the temperature of the electronic component 32 of the BMS 30 is greater than or equal to a preset value, the BMS 30 controls the semiconductor cooling chip 60 to cool and heat at the first end 61 and the second end 62 respectively. Therefore, the cold energy generated by the semiconductor cooling plate 60 at the cold end can be conducted to the BMS 30 through the first heat sink 40, and the temperature of the cold energy at the cold end can be lower than the ambient temperature, so even if the electronic components 32 of the BMS 30 are in extreme working conditions, It can also quickly cool down the electronic components 32, avoiding the problem that the heat dissipation effect of the electronic components 32 is not high when the first heat sink 40 alone is used to dissipate heat, realize the thermal management of the BMS 30 under extreme working conditions, and prolong the use of the BMS 30 life.

Specifically, as shown in FIGS. 4 to 5B , the peltier 60 further includes a first terminal 63 and a second terminal 64 with opposite polarities. For example, the first terminal 63 may be a positive terminal, and the second terminal 64 may be a negative terminal. The first terminal 63 is connected to the positive terminal of the BMS 30 , and the positive terminal of the BMS is further connected to the positive terminal of the battery cell 20 . The second terminal 64 is connected to the negative terminal of the BMS 30 , and the negative terminal of the BMS is further connected to the negative terminal of the battery cell 20 .

As shown in FIGS. 1 to 3 , in at least one embodiment of the present application, a first phase-change material layer 70 is provided between the peltier 60 and the first heat sink 40 .

When in the passive cooling mode, the heat generated by the electronic component 32 is conducted to the first heat sink 40 through the first phase change material layer 70 . Since the first phase change material layer 70 includes a thermally conductive phase change material, when heat is conducted to the first phase change material layer 70, the thermally conductive phase change material in the first phase change material layer 70 absorbs latent heat and changes from a solid state to a liquid state, thereby The heat on the electronic component 32 is quickly dissipated, and at the same time, the temperature of the thermally conductive phase change material is maintained within a certain range. In addition, when the thermally conductive phase change material of the first phase change material layer 70 completes the phase transformation, it can continue to conduct heat to the first heat sink 40 as a thermally conductive material.

Further, a second phase-change material layer 80 is provided between the peltier 60 and the second heat sink 50 .

When in the active cooling mode, the heat of the semiconductor cooling chip 60 is conducted to the second heat sink 50 through the second phase change material layer 80 . Since the second phase change material layer 80 includes a thermally conductive phase change material, when heat is conducted to the second phase change material layer 80, the thermally conductive phase change material in the second phase change material layer 80 absorbs latent heat and changes from solid to liquid, thereby Rapidly dissipate the heat of the semiconductor cooling chip 60, and at the same time maintain the temperature of the thermally conductive phase change material within a certain range, so that the semiconductor cooling chip 60 can work normally. In addition, when the thermally conductive phase change material of the second phase change material layer 80 completes the phase transformation, it can continue to conduct heat to the second heat sink 50 as a thermally conductive material.

Referring to FIG. 6 , in at least one embodiment of the present application, the first heat sink 40 includes a first base 41 and a first cooling fin 42 located on the first base 41 , and a first housing is also provided on the first base 41 . The slot 410 , the first end 61 is located in the first accommodating slot 410 .

Further, please refer to FIG. 7 , the second heat sink 50 includes a second base 51 and a second cooling fin 52 located on the second base 51 , the second base 52 is also provided with a second accommodation groove 510 , the second end 62 is located in the second receiving groove 510 . Therefore, the peltier 60 can be positioned in the first accommodating groove 410 and the second accommodating groove 510 .

Wherein, the number of the first heat sink 42 and the second heat sink 52 is multiple and has a smaller thickness-to-height ratio, therefore, the surface area of the first heat sink 42 and the second heat sink 52 is larger, and can quickly Dissipate heat. The number of the first accommodating groove 410 and the second accommodating groove 510 can be set according to the number of the peltiers 60 . The figure shows that there are two semiconductor cooling chips 60 , so the number of the first accommodating groove 410 and the number of the second accommodating groove 510 are also two.

In at least one embodiment of the present application, a thermally conductive material (not shown) may be provided between the first end 61 and the first accommodating groove 410 , and a Thermally conductive material (not shown). The thermally conductive material can be thermally conductive gel. The thermally conductive material is used to fill the gap between the first end 61 and the first accommodating groove 410 , and the gap between the second end 62 and the second accommodating groove 510 , so as to improve the distance between the semiconductor cooling sheet 60 and the first heat sink 40 . The heat conduction efficiency between and the heat conduction efficiency between the semiconductor cooling fin 60 and the second heat sink 50 .

The present application also provides a heat dissipation method for the battery pack 100, including the following steps:

Step S1: The BMS 30 controls the peltier 60 to cool at the first end 61 and heat at the second end 62 respectively.

In at least one embodiment of the present application, when the temperature value of the BMS 30 is greater than or equal to a preset value, the BMS 30 controls the conduction between the battery cell 20 and the semiconductor cooling chip 60, and the battery cell 20 supplies power to the semiconductor cooling chip 60, so that Heat is transferred from one end of the peltier 60 to the other. That is to say, the peltier 60 cools at the first end 61 and heats at the second end 62 respectively.

Step S2: the first end 61 conducts cold energy to the first heat sink 40 and the BMS 30 , and the second end 62 conducts heat to the second heat sink 50 .

That is, at this time, the battery pack 100 enters the active cooling mode. On the one hand, the temperature of the electronic component 32 is reduced by conducting the cold energy generated by the semiconductor cooling chip 60 at the first end 61 to the BMS 30 through the first heat sink 40 . On the other hand, the heat generated by the semiconductor cooling fin 60 at the second end 62 is conducted to the second heat sink 50 and dissipated by the second heat sink 50 into the air of the external environment.

More specifically, the heat of the peltier 60 is conducted to the second radiator 50 through the second phase change material layer 80 . When the heat conducts to the second phase change material layer 80, the thermally conductive phase change material in the second phase change material layer 80 absorbs latent heat and changes from solid to liquid, thereby rapidly dissipating the heat of the semiconductor refrigeration chip 60, while the thermally conductive phase The temperature of the variable material is maintained within a certain range, so that the semiconductor cooling chip 60 can work normally. In addition, when the thermally conductive phase change material of the second phase change material layer 80 completes the phase transformation, it can continue to conduct heat to the second heat sink 50 as a thermally conductive material.

In at least one embodiment of the present application, the heat dissipation method further includes:

Step S3: When the temperature of the BMS 30 drops below the preset value, the BMS 30 stops conducting the electric cell 20 and the semiconductor cooling chip 60 .

When the BMS 30 stops conducting the electric core 20 and the peltier 60 , the peltier 60 does not work, that is, the peltier 60 stops cooling and heating at the first end 61 and the second end 62 at this time.

Step S4: The BMS 30 conducts heat to the first radiator 40 .

That is, when the temperature of the BMS 30 drops below the preset value through the active cooling mode, the battery pack 100 can switch to the passive cooling mode.

When in the passive heat dissipation mode, the heat generated by the electronic components 32 is conducted to the first heat sink 40 and dissipated into the air inside the casing 10 by the first heat sink 40 . More specifically, the heat generated by the electronic component 32 is conducted to the first heat sink 40 through the first phase change material layer 70 . When heat is conducted to the first phase-change material layer 70 , the heat-conducting phase-change material in the first phase-change material layer 70 absorbs latent heat and changes from a solid state to a liquid state, thereby quickly dissipating heat on the electronic component 32 . In addition, when the thermally conductive phase change material of the first phase change material layer 70 completes the phase transformation, it can continue to conduct heat to the first heat sink 40 as a thermally conductive material.

In at least one embodiment of the present application, a temperature sensor (not shown) is disposed on the electronic component 32 of the BMS 30 , and the temperature sensor is electrically connected to the circuit board 31 of the BMS 30 . The temperature sensor is used to sense the temperature value of the electronic component 32 . The circuit board 31 receives the temperature value of the electronic component 32 sensed by the temperature sensor, and turns on the electric core 20 and the semiconductor cooling chip 60 when the temperature value is greater than or equal to a preset value.

Further, when the circuit board 31 judges that the temperature sensed by the temperature sensor drops below the preset value, it stops conducting the electric cell 20 and the peltier 60, so that the peltier 60 does not work at this time.

In addition, those skilled in the art can make various other corresponding changes and modifications according to the technical concept of the application, and all these changes and modifications should fall within the protection scope of the claims of the application.

Claims (8)

1. A battery pack, comprising a casing and a cell and a BMS disposed in the casing, the BMS is electrically connected to the cell, characterized in that, The battery pack also includes a first heat sink disposed inside the casing, a second heat sink disposed outside the casing, and a semiconductor cooling device located between the first heat sink and the second heat sink sheet, a first phase-change material layer is provided between the BMS and the first heat sink, a second phase-change material layer is provided between the semiconductor cooling sheet and the second heat sink, and the semiconductor cooling The sheet includes a first end connected to the first heat sink and a second end connected to the second heat sink, the first heat sink includes a first base and a first heat sink on the first base, The first base is also provided with a first accommodation groove, the first accommodation groove and the first heat sink are located on the side of the first base away from the BMS, and the second heat sink includes The second base and the second heat sink on the second base, the second base is also provided with a second accommodation groove, and the semiconductive refrigeration sheet is positioned in the first accommodation groove and the second accommodation groove. put in the tank; The BMS is also electrically connected to the semiconductor cooling chip, and the BMS is used to control the cooling of the semiconductor cooling chip at the first end and the heating at the second end, and the first radiator is connected to the BMS, when the temperature value of the BMS is greater than or equal to a preset value, the cold energy generated at the first end is conducted to the BMS through the first heat sink, so as to cool down the electronic components on the BMS , the heat generated at the second end can be conducted to the second heat sink and dissipated by the second heat sink. 2. The battery pack according to claim 1, wherein: When the temperature value of the BMS is greater than or equal to a preset value, the BMS is also used to control the conduction between the battery cell and the semiconductor cooling chip. 3. The battery pack according to claim 1, wherein a thermally conductive material is disposed between the first end and the first accommodating groove. 4. The battery pack according to claim 1, wherein a thermally conductive material is disposed between the second end and the second accommodating groove. 5. A heat dissipation method for a battery pack according to any one of claims 1 to 4, characterized in that it comprises the following steps: The BMS controls the semiconductor cooling chip to cool at the first end and heat at the second end; and The first end conducts cold energy to the first heat sink and the BMS, and the second end conducts heat to the second heat sink. 6. The heat dissipation method according to claim 5, wherein the BMS controls the semiconductor cooling chip to cool at the first end and heat at the second end respectively, further comprising: When the temperature value of the BMS is greater than or equal to a preset value, the BMS controls the conduction between the battery cell and the semiconductor cooling chip. 7. The heat dissipation method according to claim 6, further comprising: When the temperature value of the BMS decreases to less than the preset value, the BMS stops conducting the electric core and the semiconductor cooling chip. 8. The heat dissipation method according to claim 7, further comprising: The BMS conducts heat to the first heat sink.

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