Power supply device

Abstract

A power supply device is provided with a battery cell, a heat sink, a bonding member for bonding the battery cell and the heat sink, and a heater for heating the battery cell, and the bonding member has a first metal plate bonded to the battery cell and a second metal plate bonded to the heat sink. The thermal resistance generated by the first metal plate and the second metal plate can be changed on the basis of the temperature of the single battery.

Description

Technical Field

[0001] The present disclosure relates to a power supply device including a heat sink in a single battery. Background Art

[0002] Japanese Patent Application Laid-Open No. 2014-192010 discloses a battery cooling structure for cooling a battery. Japanese Patent Application Laid-Open No. 2014-192010 describes a structure in which a battery and a heat sink are thermally coupled via an insulating heat conductive member.

[0003] In order to increase the output of the battery, a heating device such as a heater may be used to increase the temperature of a single cell. In this case, if the heat sink is thermally coupled to the single cell, the heat of the heating device is dissipated from the heat sink. As a result, the energy efficiency for heating the single cell is reduced, and it takes time for the single cell to reach the desired temperature. Summary of the invention

[0004] The present disclosure has been made in view of the above problems, and an object of the present disclosure is to provide a power supply device capable of maintaining heat dissipation performance when cooling a cell and suppressing a decrease in energy efficiency when raising the temperature of a cell using a heating device.

[0005] In order to solve the above-mentioned problems, one aspect of the disclosed technology is a power supply device including:

[0006] Single battery;

[0007] heat sink;

[0008] A joining member for joining the single battery and the heat sink; and

[0009] A heater for heating a single battery,

[0010] The joining member includes a first metal plate joined to the unit cell and a second metal plate joined to the heat sink, and can change the thermal resistance generated by the first metal plate and the second metal plate based on the temperature of the unit cell.

[0011] According to the power supply device disclosed above, the thermal resistance of the joining member can be dynamically changed according to the temperature of the cell, thereby maintaining the heat dissipation performance when cooling the cell and suppressing the reduction of energy efficiency when raising the temperature of the cell using the heating device. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Features, advantages, and technical and industrial significance of embodiments of the present invention will be described below with reference to the accompanying drawings, wherein like reference numerals represent like elements, and wherein:

[0013] Figure 1This is a schematic structural diagram of a power supply device according to one embodiment of the present disclosure.

[0014] Figure 2 This is a flowchart of a process for thermal control of a single battery executed by a power supply device.

[0015] Figure 3A It is a diagram for explaining the state of thermal coupling and the state of thermal isolation of the metal plates.

[0016] Figure 3B It is a diagram for explaining the state of thermal coupling and the state of thermal isolation of the metal plates.

[0017] Figure 4 It is a diagram for explaining the state that the power supply device takes according to the thermal control of the single battery. DETAILED DESCRIPTION

[0018] In the power supply device of the present disclosure, the joint member provided between the single cell and the radiator switches whether to make the single cell and the radiator thermally coupled or thermally isolated according to the temperature of the single cell. By this switching, the heat dissipation performance through the radiator can be maintained when cooling the single cell, and the reduction in the energy efficiency of the heater heat when heating the single cell can be suppressed.

[0019] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0020] Implementation

[0021] structure

[0022] Figure 1 It is a schematic diagram for explaining the structure of the power supply device 10 according to one embodiment of the present disclosure. Figure 1 The power supply device 10 in the embodiment includes a single battery 11, a heat sink 12, a heater 13, a bonding member 14, and heat dissipation pastes 15a and 15b.

[0023] The cell 11 is a secondary battery configured to be chargeable and dischargeable, such as a lithium ion battery.

[0024] The heat sink 12 is a heat dissipation member thermally coupled to the unit battery 11 via the bonding member 14 and the heat dissipation pastes 15a and 15b. The heat sink 12 is made of a member having good thermal conductivity, such as aluminum or copper.

[0025] The heater 13 is a heating device for heating the unit battery 11. The timing of heating the unit battery 11 by the heater 13 will be described later. In addition, the method of heating by the heater 13 is not particularly limited.

[0026] The joining component 14 is provided between the single cell 11 and the radiator 12, and is a component for joining the single cell 11 and the radiator 12. The joining component 14 includes a first metal plate 14a in contact with the single cell 11 via a heat dissipation paste 15a, and a second metal plate 14b in contact with the radiator 12 via a heat dissipation paste 15b. The first metal plate 14a and the second metal plate 14b are configured to be able to switch to either a state in which the single cell 11 and the radiator 12 are thermally coupled or a state in which the single cell 11 and the radiator 12 are thermally isolated according to the temperature of the single cell 11. That is, the joining component 14 is configured to be able to change the thermal resistance generated by the first metal plate 14a and the second metal plate 14b.

[0027] As the first metal plate 14a and the second metal plate 14b, for example, various known metal materials that can be deformed to form a layer of air as a gap between a part (or the whole) of the metal plates on both sides can be used. In addition, the first metal plate 14a and the second metal plate 14b can be formed as a combined component or two independent components. In addition, in order to ensure the heat dissipation performance in the state where the single battery 11 and the heat sink 12 are thermally coupled, it is preferable to use a component with good thermal conductivity for the first metal plate 14a and the second metal plate 14b.

[0028] The heat dissipation paste 15a is a structure for thermally coupling the single battery 11 to the first metal plate 14a of the joint member 14. The heat dissipation paste 15b is a structure for thermally coupling the second metal plate 14b of the joint member 14 to the heat sink 12. The heat dissipation pastes 15a and 15b are respectively made of materials with good insulation and thermal conductivity.

[0029] control

[0030] Next, refer to Figure 2 , Figure 3A as well as Figure 3B Control performed by the power supply device 10 of the present embodiment will be described. Figure 2 This is a flowchart for explaining the processing procedure of thermal control of the single battery 11 executed by the power supply device 10 .

[0031] S201

[0032] The power supply device 10 obtains the temperature of the main body of the single cell 11 (hereinafter referred to as the "single cell temperature") and the temperature of the environment in which the single cell 11 is placed (hereinafter referred to as the "ambient temperature"). The single cell temperature and the ambient temperature can be obtained using a detection device such as a temperature sensor (not shown). Among them, the detection device for detecting the single cell temperature is set at a position in contact with the single cell 11 or near the single cell 11. In addition, the detection device for detecting the ambient temperature can be set near the single cell 11 or at other locations (such as the outside of the power supply device 10).

[0033] When the cell temperature and the ambient temperature are acquired in the power supply device 10 , the process proceeds to S202 .

[0034] S202

[0035] The power supply device 10 determines whether the cell temperature is higher than a predetermined first threshold temperature. This determination is made to confirm whether the heater 13 should be driven. Therefore, the first threshold temperature is set to the temperature of the cell 11 (low temperature limit value) that generates the need to drive the heater 13 for heating.

[0036] If the power supply device 10 determines that the cell temperature is higher than the first threshold temperature (S202, Yes), the process proceeds to S203. On the other hand, if the power supply device 10 determines that the cell temperature is lower than the first threshold temperature (S202, No), the process proceeds to S206.

[0037] S203

[0038] The power supply device 10 determines whether the cell temperature is equal to or higher than the ambient temperature. This determination is performed to confirm whether the heat of the cell 11 should be released from the radiator 12 (normal state) in order to prevent the temperature of the cell 11 from rising.

[0039] If the power supply device 10 determines that the cell temperature is equal to or higher than the ambient temperature (S203, Yes), the process proceeds to S204. On the other hand, if the power supply device 10 determines that the cell temperature is lower than the ambient temperature (S203, No), the process proceeds to S208.

[0040] S204

[0041] The power supply device 10 determines whether the cell temperature is higher than a predetermined second threshold temperature. This determination is made to confirm whether the cell 11 needs to be cooled based on the body temperature of the cell 11. The second threshold temperature is set to a value higher than the first threshold temperature.

[0042] If the power supply device 10 determines that the cell temperature is higher than the second threshold temperature (S204, Yes), the process proceeds to S207. On the other hand, if the power supply device 10 determines that the cell temperature is lower than the second threshold temperature (S204, No), the process proceeds to S205.

[0043] S205

[0044] The power supply device 10 determines whether the ambient temperature is higher than the first threshold temperature. This determination is performed to determine a method for preventing the temperature of the cell 11 from rising based on the ambient temperature.

[0045] If the power supply device 10 determines that the ambient temperature is higher than the first threshold temperature (S205, Yes), the process proceeds to S207. On the other hand, if the power supply device 10 determines that the ambient temperature is lower than the first threshold temperature (S205, No), the process proceeds to S208.

[0046] S206

[0047] The power supply device 10 drives the heater 13 (turns on the heating). The heater 13 can also be driven by a control unit (not shown) such as a microcomputer that obtains the single cell temperature from the detection device to control the heater 13. Alternatively, the heater 13 itself can also be driven by obtaining the single cell temperature from the detection device.

[0048] If the heater 13 is driven in the power supply device 10 , the process proceeds to S208 .

[0049] S207

[0050] The power supply device 10 makes the first metal plate 14a and the second metal plate 14b of the joint member 14 be in a state of thermal coupling (thermal coupling state). In this thermal coupling state, the first metal plate 14a and the second metal plate 14b are in a state of close contact with each other with almost no gap, and the thermal resistance generated by the first metal plate 14a and the second metal plate 14b becomes small. Figure 3A , an example of the structure of the power supply device 10 in this thermal coupling state is shown. Figure 3A As shown, in the thermal coupling state, the heat of the unit battery 11 can be released from the heat sink 12 via the joint member 14 (first metal plate 14a, second metal plate 14b) and the heat dissipation paste 15a, 15b. In other words, the thermal coupling state can be said to be a normal state.

[0051] Typically, the transition from the current state to the thermal coupling state is achieved by the first metal plate 14a and the second metal plate 14b that detect the single cell temperature and the ambient temperature deforming their shapes. Alternatively, the transition from the current state to the thermal coupling state may be achieved by controlling the first metal plate 14a and the second metal plate 14b by a control unit (not shown) that detects the single cell temperature and the ambient temperature.

[0052] When the first metal plate 14 a and the second metal plate 14 b are thermally coupled in the power supply device 10 , the thermal control of the cell 11 is terminated.

[0053] S208

[0054] The power supply device 10 makes the first metal plate 14a and the second metal plate 14b of the joint member 14 be in a state of thermal isolation (thermal isolation state). In this thermal isolation state, a gap is formed between part or all of the first metal plate 14a and the second metal plate 14b to generate an air layer, and the thermal resistance generated by the first metal plate 14a and the second metal plate 14b becomes large. Figure 3B , an example of the structure of the power supply device 10 in the thermal isolation state is shown. Figure 3B As shown, in the thermal isolation state, a layer of air is formed. As a result, the heat released (dissipated) from the radiator 12 can be reduced via the joint component 14 (the first metal plate 14a, the second metal plate 14b) and the heat dissipation paste 15a, 15b. Therefore, when the single cell 11 is heated by the heater 13 (S206, No), the single cell 11 can be efficiently heated. In addition, when the external air temperature is higher than the temperature of the single cell 11 (S203, No), the single cell 11 can be prevented from being heated by the external air. In addition, when the temperature of the single cell 11 is not reduced even if the external air temperature is lower than the temperature of the single cell 11 (S205, No), the single cell 11 can be prevented from being cooled by the external air and becoming low temperature.

[0055] Typically, the transition from the current state to the thermal isolation state is achieved by the first metal plate 14a and the second metal plate 14b that detect the single cell temperature and the ambient temperature deforming their shapes. Alternatively, the transition from the current state to the thermal isolation state may be achieved by controlling the first metal plate 14a and the second metal plate 14b by a control unit (not shown) that detects the single cell temperature and the ambient temperature.

[0056] When the first metal plate 14 a and the second metal plate 14 b are thermally isolated from each other in the power supply device 10 , the thermal control of the unit cells 11 is terminated.

[0057] exist Figure 4, the state obtained by the power supply device 10 according to the thermal control of the single battery 11 described above is shown. Figure 4 As shown, the power supply device 10 appropriately selects the thermal coupling state and the thermal isolation state based on the temperature of the cell 11 (cell temperature), the outside air temperature (ambient temperature), the first threshold temperature, and the second threshold temperature.

[0058] Function and effect

[0059] As described above, the power supply device 10 of one embodiment of the present disclosure sandwiches the joining member 14 composed of two separable metal plates (the first metal plate 14a and the second metal plate 14b) between the single battery 11 and the heat sink 12. In addition, the power supply device 10 switches between the thermal coupling state and the thermal isolation state according to the temperature of the single battery and the ambient temperature.

[0060] When it is desired to dissipate the heat of the single cell 11 to the outside air and lower the temperature of the single cell by this treatment, the two metal plates (the first metal plate 14a and the second metal plate 14b) of the joint member 14 are thermally coupled to eliminate the gap. Thus, heat can be dissipated from the heat sink 12. In addition, when it is desired to increase the temperature of the single cell without dissipating the heat of the single cell 11 to the outside air, the two metal plates (the first metal plate 14a and the second metal plate 14b) of the joint member 14 are thermally isolated to generate a gap. Thus, by using the air layer for heat insulation, the amount of heat dissipated from the heat sink 12 can be reduced.

[0061] Therefore, it is possible to maintain the heat dissipation performance (low thermal resistance) when cooling the cells 11 , shorten the time for heating the cells 11 using the heater 13 , and reduce the power consumption of the heater 13 (suppress the reduction in energy efficiency).

[0062] The power supply device of the present disclosure can be used in the case where it is desired to achieve both heat dissipation when cooling the unit cells and temperature rise when heating the unit cells.

Claims

1. A power supply device, wherein: have: Single battery; heat sink; A joining member for joining the unit battery to the heat sink; and a heater for heating the single battery, The joining member includes a first metal plate joined to the unit cell and a second metal plate joined to the heat sink, and is capable of changing thermal resistance generated by the first metal plate and the second metal plate based on a temperature of the unit cell.

2. The power supply device according to claim 1, wherein: When the temperature of the single cell is lower than a predetermined first threshold temperature, The heater heats the single battery. The joining member thermally isolates the first metal plate from the second metal plate, thereby increasing thermal resistance compared to before the thermal isolation.

3. The power supply device according to claim 1, wherein: When the temperature of the cell and the ambient temperature exceed a predetermined first threshold temperature and the temperature of the cell is equal to or higher than the ambient temperature, The heater does not heat the single battery. The joining member thermally couples the first metal plate and the second metal plate to reduce thermal resistance compared to before the thermal coupling.

4. The power supply device according to claim 3, wherein: When the ambient temperature is lower than the first threshold temperature and the temperature of the single cell exceeds a second threshold temperature higher than the first threshold temperature, The heater does not heat the single battery. The joining member thermally couples the first metal plate and the second metal plate to reduce thermal resistance compared to before the thermal coupling.

5. The power supply device according to claim 1, wherein: When the temperature of the single cell exceeds a predetermined first threshold temperature and is lower than the ambient temperature, The heater does not heat the single battery. The joining member thermally isolates the first metal plate from the second metal plate, thereby increasing thermal resistance compared to before the thermal isolation.

6. The power supply device according to claim 5, wherein: When the temperature of the single cell is equal to or higher than the ambient temperature and the ambient temperature is equal to or lower than the first threshold temperature, The heater does not heat the single battery. The joining member thermally isolates the first metal plate from the second metal plate, thereby increasing thermal resistance compared to before the thermal isolation.

Images