Battery thermal management system and electric vehicle

Abstract

This invention relates to the field of battery thermal management system technology, and more particularly to a battery thermal management system and an electric vehicle. The battery thermal management system mainly includes a battery pack, a drive unit, an ambient temperature sensor, a controller, a normal temperature cooling module, a low-temperature cooling module, and a low-temperature heating module. The battery pack is equipped with an inlet and an outlet for coolant flow. One end of the drive unit is connected to the inlet, and the other end is simultaneously connected to the normal temperature cooling module, the low-temperature cooling module, and the low-temperature heating module, which are connected in parallel. The ambient temperature sensor monitors the ambient temperature, and the controller is electrically connected to the ambient temperature sensor, the drive unit, the normal temperature cooling module, the low-temperature cooling module, and the low-temperature heating module. The structure is simple, solving the problem of compressors not being able to operate for extended periods in low-temperature environments, reducing energy consumption, extending the battery pack's lifespan, and improving safety performance.

Description

Technical Field

[0001] This invention relates to the field of battery thermal management system technology, and more particularly to a battery thermal management system and an electric vehicle. Background Technology

[0002] With the development of new energy vehicles and the increase in battery energy density, the charging and discharging processes generate a large amount of heat, leading to reduced battery pack life, uneven internal temperature, and an increased risk of thermal runaway. Furthermore, in northern regions, lower winter temperatures reduce the rate of internal chemical reactions within the battery, resulting in a decrease in the battery's discharge rate. As a crucial component of the battery thermal management system, the water-cooled unit must meet the cooling and heating requirements of the battery pack under varying environmental conditions.

[0003] Currently, battery thermal management systems on the market use a compressor to compress refrigerant to provide circulation power for the refrigerant circuit and a water pump to provide circulation power for the antifreeze circuit. When the ambient temperature is low and the battery pack needs heating, the unit adopts PTC heating mode. The refrigerant circuit stops operating, and the PTC connected in series in the water circuit starts to heat the low-temperature coolant in the battery pack circuit, thus achieving the heating function.

[0004] Existing technologies have shortcomings:

[0005] 1. When the ambient temperature is not high, the cooling demand of the battery pack is not large during the charging and discharging process. If the cooling capacity is provided by starting the compressor, the compressor will start and stop frequently. Over time, the compressor is prone to failure. In addition, the air conditioning system has low energy efficiency and low economic value in this mode.

[0006] 2. Some high-energy-density batteries still require cooling capacity even when the ambient temperature is low in winter (below -10℃) and the battery pack temperature is relatively high during charging and discharging. However, due to the technical limitations of refrigeration compressors, many compressors cannot operate for a long time in an environment with an ambient temperature below -10℃. If the compressor is forced to operate in a low-temperature environment for a long time, the compressor is prone to failure and may even lead to functional loss.

[0007] 3. The PTC heater is connected in series in the water circuit, which increases the flow resistance of the water circuit. Under the premise of a certain water pump head, the flow rate of antifreeze in the water circuit will be insufficient, resulting in a decrease in the heating capacity of the battery thermal management system in heating mode.

[0008] Therefore, there is an urgent need to design a battery thermal management system and an electric vehicle to solve the technical problems in the existing technology. Summary of the Invention

[0009] The purpose of this invention is to propose a battery thermal management system and an electric vehicle. The system has a simple structure and can solve the problem that the compressor cannot operate effectively for a long time in low-temperature environments, reduce the energy consumption of the battery thermal management system, extend the service life of the battery pack, and improve safety performance.

[0010] To achieve this objective, the present invention adopts the following technical solution:

[0011] This invention provides a battery thermal management system, comprising:

[0012] A battery pack, wherein the battery pack is provided with an inlet and an outlet for coolant flow;

[0013] A driving device, one end of which is connected to the water inlet, and the other end of which is simultaneously connected to the ambient temperature refrigeration module, the low temperature refrigeration module, and the low temperature heating module, respectively. The ambient temperature refrigeration module, the low temperature refrigeration module, and the low temperature heating module are arranged in parallel. The outlets of the three modules are all connected to the water outlet.

[0014] An ambient temperature sensor is mounted on the housing of the battery thermal management system for monitoring the ambient temperature.

[0015] The controller is electrically connected to the ambient temperature sensor, the drive device, the ambient temperature refrigeration module, the low temperature refrigeration module, and the low temperature heating module.

[0016] When the ambient temperature sensor detects that the ambient temperature is a first preset temperature, the ambient temperature sensor transmits the first preset temperature signal to the controller, and the controller controls the drive device and the ambient temperature cooling module to start.

[0017] When the ambient temperature sensor detects that the ambient temperature is the second preset temperature, the ambient temperature sensor transmits the second preset temperature signal to the controller, and the controller controls the drive device and the low-temperature refrigeration module to start.

[0018] When the ambient temperature sensor detects that the ambient temperature is the third preset temperature, the ambient temperature sensor transmits the third preset temperature signal to the controller, and the controller controls the drive device and the low-temperature heating module to start.

[0019] As an optional technical solution for a battery thermal management system, the ambient temperature refrigeration module includes a condenser, a compressor, and a heat exchanger connected in sequence. The condenser, the compressor, and the heat exchanger form a closed loop for the circulation of refrigerant. One end of the heat exchanger is connected to the drive device, and the other end is connected to the outlet. The coolant can flow from the drive device through the heat exchanger to the outlet.

[0020] As an optional technical solution for a battery thermal management system, an expansion valve is provided downstream of the condenser along the flow direction of the refrigerant.

[0021] As an optional technical solution for a battery thermal management system, the low-temperature refrigeration module includes a low-temperature water tank, one end of which is connected to the drive device and the other end of which is connected to the water outlet.

[0022] As an optional technical solution for a battery thermal management system, the cryogenic refrigeration module further includes a first solenoid valve, which is located upstream of the cryogenic water tank along the flow direction of the coolant.

[0023] As an optional technical solution for a battery thermal management system, the low-temperature heating module includes a PTC heater, one end of which is connected to the drive device and the other end of which is connected to the water outlet.

[0024] As an optional technical solution for the battery thermal management system, the low-temperature heating module further includes a second solenoid valve, which is located upstream of the PTC heater along the flow direction of the coolant.

[0025] As an optional technical solution for a battery thermal management system, the battery thermal management system further includes a condenser fan, and the controller is electrically connected to the condenser fan. When the ambient temperature sensor detects that the ambient temperature is a first preset temperature or a second preset temperature, the controller controls the condenser fan to start.

[0026] As an optional technical solution for a battery thermal management system, an inlet water temperature sensor is provided on the water inlet, and an outlet water temperature sensor is provided on the water outlet. Both the inlet water temperature sensor and the outlet water temperature sensor are electrically connected to the controller.

[0027] The present invention also provides an electric vehicle, the electric vehicle including the battery thermal management system described above.

[0028] The beneficial effects of this invention are as follows:

[0029] This invention provides a battery thermal management system with a simple structure. By connecting a normal-temperature cooling module, a low-temperature cooling module, and a low-temperature heating module in parallel, the flow resistance of the coolant in various operating modes is reduced, thereby improving the heat exchange capacity of the coolant. Furthermore, this battery thermal management system is applicable to both high-temperature and extremely cold environments, broadening its operating temperature range and enhancing its flexibility. In extremely cold environments (-30℃ ≤ ambient temperature < -10℃), the coolant exchanges heat by entering a low-temperature water tank, solving the problem of compressor malfunction in such environments, extending compressor lifespan, saving costs, and simultaneously conserving energy, thus improving the energy efficiency ratio of the battery thermal management system.

[0030] The present invention also provides an electric vehicle including the above-mentioned battery thermal management system. This battery thermal management system in the electric vehicle can operate in both cooling and heating modes for the battery pack, meeting the cooling and heating needs under different environmental temperatures such as high and low temperatures, greatly improving the service life and safety performance of the electric vehicle. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the working process of the battery thermal management system provided in an embodiment of the present invention.

[0033] Figure Labels

[0034] 100, Water inlet; 110, Water inlet temperature sensor; 200, Water outlet; 210, Water outlet temperature sensor;

[0035] 300. Drive unit;

[0036] 400. Ambient temperature refrigeration module; 410. Condenser; 420. Compressor; 430. Heat exchanger; 440. Expansion valve; 450. High-pressure switch; 460. Low-pressure switch;

[0037] 500. Low-temperature refrigeration module; 510. Low-temperature water tank; 520. First solenoid valve;

[0038] 600. Low-temperature heating module; 610. PTC heater; 620. Second solenoid valve;

[0039] 700. Ambient temperature sensor; 800. Condenser fan. Detailed Implementation

[0040] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0041] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0042] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0043] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0044] like Figure 1As shown, this embodiment provides a battery thermal management system, mainly including a battery pack, a drive device 300, an ambient temperature sensor 700, a controller (not shown in the figure), a room temperature cooling module 400, a low temperature cooling module 500, and a low temperature heating module 600. The battery pack is provided with an inlet 100 and an outlet 200 for coolant flow. One end of the drive device 300 is connected to the inlet 100, and the other end is simultaneously connected to the room temperature cooling module 400, the low temperature cooling module 500, and the low temperature heating module 600, which are arranged in parallel. The outlets of all three modules are connected to the outlet 200. An ambient temperature sensor 700 is mounted on the housing of the battery thermal management system (not shown in the figure) and is used to monitor the ambient temperature. The controller is electrically connected to the ambient temperature sensor 700, the drive device 300, the ambient temperature cooling module 400, the low temperature cooling module 500, and the low temperature heating module 600.

[0045] Optionally, such as Figure 1 As shown, in this embodiment, an inlet water temperature sensor 110 is provided on the inlet 100, and an outlet water temperature sensor 210 is provided on the outlet 200. Both the inlet water temperature sensor 110 and the outlet water temperature sensor 210 are electrically connected to the controller.

[0046] Optionally, the driving device 300 in this embodiment is a water pump. The battery pack can be a cylindrical battery pack or a square battery pack, etc., and this embodiment is not limited to this.

[0047] Based on the above design, the working process of the battery thermal management system in this embodiment is as follows:

[0048] (1) When the ambient temperature sensor 700 monitors the ambient temperature as the first preset temperature, optionally, in this embodiment, the first preset temperature is set to ≥-10℃, and the water inlet temperature of the battery pack water inlet 100 is ≥15℃. At this time, the ambient temperature sensor 700 transmits the first preset temperature signal, and the water inlet temperature sensor 110 transmits the water inlet temperature signal to the controller at the same time. The controller controls the drive device 300 and the ambient temperature cooling module 400 to start.

[0049] Furthermore, the ambient temperature refrigeration module 400 includes a condenser 410, a compressor 420, and a heat exchanger 430 connected in sequence. These three components form a closed loop for refrigerant flow. One end of the heat exchanger 430 is connected to the drive unit 300, and the other end is connected to the outlet 200, allowing coolant to flow from the drive unit 300 through the heat exchanger 430 to the outlet 200. An expansion valve 440 is located downstream of the condenser 410 along the refrigerant flow direction. The compressor 420 compresses the refrigerant to provide the circulation power for the coolant circuit, and the drive unit 300 provides the circulation power for the coolant circuit. The high-temperature, high-pressure gas discharged from the compressor 420 dissipates heat through the condenser 410, converting it into a high-pressure, low-temperature liquid refrigerant. This high-pressure, low-temperature liquid refrigerant then undergoes throttling and pressure reduction through the expansion valve 440 and enters the heat exchanger 430 to exchange heat with the high-temperature coolant in the battery pack circuit, thereby providing cooling for the battery pack. When the temperature of the coolant in the heat exchange is below 15°C, the outlet water temperature sensor 210 transmits the outlet water temperature signal to the controller, and the controller controls the valve (not shown in the figure) at the outlet 200 to open, thereby allowing the coolant to flow back into the battery pack.

[0050] Optionally, in this embodiment, the heat exchanger 430 is a plate heat exchanger 430, in which the refrigerant flows in the tube side and the coolant flows in the shell side. In this embodiment, a low-pressure switch 460 and a high-pressure switch 450 are also provided in the refrigerant flow circuit, which helps to control the pressure and temperature of the refrigerant in the refrigerant circuit and improve the heat exchange efficiency between the refrigerant and the coolant.

[0051] (2) When the ambient temperature sensor 700 monitors the ambient temperature as the second preset temperature, optionally, in this embodiment, the range of the second preset temperature is set to -30℃≤ambient temperature<-10℃, and the water inlet temperature of the battery pack water inlet 100 is ≥15℃. At this time, the ambient temperature sensor 700 transmits the second preset temperature signal to the controller, and the water inlet temperature sensor 110 transmits the water inlet temperature signal to the controller at the same time. The controller controls the drive device 300 and the low temperature refrigeration module 500 to start.

[0052] Furthermore, such as Figure 1As shown, in this embodiment, the cryogenic refrigeration module 500 includes a cryogenic water tank 510 and a first solenoid valve 520. One end of the cryogenic water tank 510 is connected to the drive device 300, and the other end is connected to the water outlet 200. Along the flow direction of the coolant, the first solenoid valve 520 is located upstream of the cryogenic water tank 510. The first solenoid valve 520 is electrically connected to the controller. When the ambient temperature is a second preset temperature, and the inlet water temperature of the battery pack inlet 100 is ≥15℃, the controller controls the first solenoid valve 520 and the drive device 300 to open, allowing the coolant to enter the cryogenic water tank 510. The coolant exchanges heat with the outside air in the cryogenic water tank 510, thereby reducing the coolant temperature. Since the ambient temperature refrigeration module 400 is in a closed state at this time, energy consumption is saved, compressor 420 is prevented from malfunctioning in extremely cold weather, costs are saved, and service life is extended. When the temperature of the coolant in the heat exchange is below 15°C, the outlet water temperature sensor 210 transmits the outlet water temperature signal to the controller, and the controller controls the valve (not shown in the figure) at the outlet 200 to open, thereby allowing the coolant to flow back into the battery pack.

[0053] (3) When the ambient temperature sensor 700 monitors the ambient temperature as the third preset temperature, optionally, in this embodiment, the range of the third preset temperature is set to -40℃≤ambient temperature<-10℃, and the water inlet temperature of the battery pack water inlet 100 is <5℃. At this time, the ambient temperature sensor 700 transmits the third preset temperature signal to the controller, and the water inlet temperature sensor 110 transmits the water inlet temperature signal to the controller at the same time. The controller controls the drive device 300 and the low temperature heating module 600 to start.

[0054] Furthermore, the low-temperature heating module 600 includes a PTC heater 610 and a second solenoid valve 620. One end of the PTC heater 610 is connected to the drive device 300, and the other end is connected to the water outlet 200. The second solenoid valve 620 is positioned upstream of the PTC heater 610 along the flow direction of the coolant. The second solenoid valve 620 is electrically connected to the controller. When the ambient temperature is a third preset temperature, and the inlet water temperature of the battery pack inlet 100 is <5℃, the controller controls the second solenoid valve 620 and the drive device 300 to open. The drive device 300 drives the coolant through the second solenoid valve 620 to the PTC heater 610, thereby increasing the coolant temperature and preventing the risk of coolant solidification due to excessively low temperatures. In this embodiment, the low-temperature heating module 600, the ambient temperature cooling module 400, and the low-temperature cooling module 500 are all connected in parallel, thereby reducing the flow resistance of the coolant in the pipeline and improving the heat exchange efficiency of the battery thermal management system.

[0055] Compared with existing technologies, the battery thermal management system provided in this embodiment has a simple structure. By connecting the ambient temperature cooling module 400, the low temperature cooling module 500, and the low temperature heating module 600 in parallel, the flow resistance of the coolant in various operating modes of the battery thermal management system is reduced, thereby improving the heat exchange capacity of the coolant. Furthermore, this battery thermal management system is applicable to both high-temperature and extremely cold environments, broadening its operating temperature range and improving its flexibility and applicability. In extremely cold environments (-30℃ ≤ ambient temperature < -10℃), the coolant undergoes heat exchange by entering the low-temperature water tank 510, solving the problem of the compressor 420 failing to operate normally in extremely cold environments, extending the service life of the compressor 420, saving costs, and simultaneously achieving the goal of saving energy consumption of the battery thermal management system, thus improving its energy efficiency ratio.

[0056] like Figure 1 As shown, in this embodiment, the battery thermal management system further includes a condenser fan 800. A controller is electrically connected to the condenser fan 800. When the ambient temperature sensor 700 detects that the ambient temperature is at a first preset temperature or a second preset temperature, the controller controls the condenser fan 800 to start. That is, when the ambient temperature cooling module 400 or the low-temperature cooling module 500 is working normally, the controller controls the condenser fan 800 to turn on, thereby further improving the heat dissipation efficiency of the coolant. In this embodiment, the condenser fan 800 is mounted on the housing of the battery thermal management system. The number of condenser fans 800 can be one or more; this embodiment does not limit this.

[0057] This embodiment also provides an electric vehicle that includes the above-described battery thermal management system. The battery thermal management system in this electric vehicle can operate in both cooling and heating modes for the battery pack, meeting the cooling and heating needs under different environmental temperatures, such as high and low temperatures, greatly improving the service life and safety performance of the electric vehicle.

[0058] Obviously, the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

[0059] Note that in the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

Claims

1. A battery thermal management system, characterized in that, include: A battery pack having an inlet (100) and an outlet (200) for coolant flow. A driving device (300) is provided, one end of which is connected to the water inlet (100), and the other end is connected to the ambient temperature refrigeration module (400), the low temperature refrigeration module (500), and the low temperature heating module (600) respectively. The ambient temperature refrigeration module (400), the low temperature refrigeration module (500), and the low temperature heating module (600) are arranged in parallel. The outlet ends of the ambient temperature refrigeration module (400), the low temperature refrigeration module (500), and the low temperature heating module (600) are all connected to the water outlet (200). An ambient temperature sensor (700) is disposed on the housing of the battery thermal management system for monitoring the ambient temperature; The controller is electrically connected to the ambient temperature sensor (700), the drive device (300), the ambient temperature refrigeration module (400), the low temperature refrigeration module (500), and the low temperature heating module (600); An inlet water temperature sensor (110) is provided on the inlet (100), and an outlet water temperature sensor (210) is provided on the outlet (200). Both the inlet water temperature sensor (110) and the outlet water temperature sensor (210) are electrically connected to the controller. The ambient temperature sensor (700) monitors the ambient temperature as a first preset temperature, which is set to ≥-10℃. When the water inlet temperature sensor (110) monitors the water inlet temperature of the battery pack's inlet (100) as ≥15℃, the ambient temperature sensor (700) transmits the first preset temperature signal and the water inlet temperature sensor (110) transmits the water inlet temperature signal to the controller. The controller then controls the drive device (300) and the ambient temperature cooling module (400) to start. The ambient temperature sensor (700) monitors the ambient temperature as a second preset temperature, the range of which is set to -30℃≤ambient temperature<-10℃, and the inlet water temperature sensor (110) monitors the inlet water temperature of the battery pack inlet (100) as ≥15℃; the ambient temperature sensor (700) transmits the second preset temperature signal and the inlet water temperature sensor (110) transmits the inlet water temperature signal to the controller at the same time, and the controller controls the drive device (300) and the low-temperature refrigeration module (500) to start; The ambient temperature sensor (700) monitors the ambient temperature as a third preset temperature, the range of which is set to -40℃≤ambient temperature<-10℃, and the water inlet temperature sensor (110) monitors the water inlet temperature of the battery pack (100) as <5℃; the ambient temperature sensor (700) transmits the third preset temperature signal and the water inlet temperature sensor (110) transmits the water inlet temperature signal to the controller at the same time, and the controller controls the drive device (300) and the low-temperature heating module (600) to start.

2. The battery thermal management system according to claim 1, characterized in that, The ambient temperature refrigeration module (400) includes a condenser (410), a compressor (420), and a heat exchanger (430) connected in sequence. The condenser (410), the compressor (420), and the heat exchanger (430) form a closed loop for the circulation of refrigerant. One end of the heat exchanger (430) is connected to the drive device (300), and the other end is connected to the outlet (200). The coolant can flow from the drive device (300) through the heat exchanger (430) to the outlet (200).

3. The battery thermal management system according to claim 2, characterized in that, An expansion valve (440) is provided downstream of the condenser (410) along the flow direction of the refrigerant.

4. The battery thermal management system according to claim 1, characterized in that, The low-temperature refrigeration module (500) includes a low-temperature water tank (510), one end of which is connected to the drive device (300) and the other end is connected to the water outlet (200).

5. The battery thermal management system according to claim 4, characterized in that, The cryogenic refrigeration module (500) also includes a first solenoid valve (520), which is located upstream of the cryogenic water tank (510) along the flow direction of the coolant.

6. The battery thermal management system according to claim 1, characterized in that, The low-temperature heating module (600) includes a PTC heater (610), one end of which is connected to the drive device (300) and the other end is connected to the water outlet (200).

7. The battery thermal management system according to claim 6, characterized in that, The low-temperature heating module (600) also includes a second solenoid valve (620), which is located upstream of the PTC heater (610) along the flow direction of the coolant.

8. The battery thermal management system according to claim 1, characterized in that, The battery thermal management system also includes a condenser fan (800), and the controller is electrically connected to the condenser fan (800). When the ambient temperature sensor (700) detects that the ambient temperature is a first preset temperature or a second preset temperature, the controller controls the condenser fan (800) to start.

9. An electric vehicle, characterized in that, The electric vehicle includes the battery thermal management system according to any one of claims 1-8.

Images