CN214176110U - Multistage cooling type battery pack - Google Patents
Multistage cooling type battery pack Download PDFInfo
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- CN214176110U CN214176110U CN202120158524.9U CN202120158524U CN214176110U CN 214176110 U CN214176110 U CN 214176110U CN 202120158524 U CN202120158524 U CN 202120158524U CN 214176110 U CN214176110 U CN 214176110U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/70—Energy storage systems for electromobility, e.g. batteries
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Abstract
A multi-stage cooling type battery pack comprises a temperature control system, a primary cooling system, a secondary cooling system and a cooling system; the cooling system is internally provided with a battery pack and a temperature sensor for sensing the temperature of the battery pack; the primary cooling system is used for receiving the flow control signal and outputting the coolant to the cooling system; the secondary cooling system is used for receiving the air volume control signal and outputting cooling air volume to the cooling system; the temperature control system is used for receiving a coolant flow signal of the primary cooling system, an air speed signal of the secondary cooling system and a temperature signal of the temperature sensor, outputting flow and air volume control signals and ensuring that the battery works within a reasonable temperature range. The heat dissipation efficiency and uniformity of the surface of the battery are improved, the optimal working temperature of the battery is ensured, the temperature difference of the surface of the battery is reduced, and the service life of the battery is prolonged; the real-time control of the battery temperature is realized, the use safety of the battery is improved, and the driving range of the electric automobile is increased.
Description
Technical Field
The utility model belongs to the technical field of new energy automobile battery cooling, in particular to multistage cooling type battery package.
Background
With the increasing problems of environmental pollution, energy shortage and the like, electric automobiles increasingly become green industries which are mainly developed by governments of various countries, and the market prospect is wide. However, due to the restriction of the battery cooling technology, the temperature of the battery cannot be guaranteed to be always within a reasonable range, spontaneous combustion and explosion accidents of the electric automobile are frequent, the use safety of the electric automobile is greatly reduced, and the service life of the battery and the driving range of the electric automobile are also reduced due to continuous high-temperature work.
At present, air cooling and liquid cooling are the battery cooling technologies commonly used for electric vehicles. The air cooling technology takes air as a cooling medium, utilizes air convection heat exchange to realize reduction of the working temperature of the battery pack, has the characteristics of simple equipment and convenient later maintenance, is limited by the properties of specific heat capacity and heat conductivity coefficient of the air, and has lower cooling efficiency on the battery pack; liquid cooling technology takes liquid substances such as ethylene glycol, water, refrigerant and the like as cooling media, compared with air, liquid cooling has the characteristics of large specific heat capacity and high heat transfer coefficient, the technical defects of low air cooling efficiency are effectively overcome, but the problems of liquid leakage, electric conduction, complex cooling system pipeline, low reliability and the like exist. Traditional battery cooling technology can be because of its near-far problem apart from heat transfer cooling surface at the during operation for the temperature between the group battery is uneven, leads to battery cooling decay rate inconsistent, has certain potential safety hazard. Therefore, it is urgently needed to develop a multi-stage cooling type battery pack and a cooling method thereof, so that the heat dissipation efficiency and uniformity of the surface of the battery are improved, the optimal working temperature of the battery is ensured, the temperature difference of the surface of the battery is reduced, and the service life of the battery is prolonged; the real-time control of the battery temperature is realized, the use safety of the battery is improved, and the driving range of the electric automobile is increased.
SUMMERY OF THE UTILITY MODEL
Aiming at the defects of the existing battery cooling technology, the utility model provides a multistage cooling type battery pack, which improves the surface heat dissipation efficiency and uniformity of the battery, ensures the optimal working temperature of the battery, reduces the surface temperature difference of the battery and prolongs the service life of the battery; the real-time control of the battery temperature is realized, the use safety of the battery is improved, and the driving range of the electric automobile is increased.
In order to achieve the above purpose, the utility model adopts the technical scheme that:
the temperature control system is used for receiving a coolant flow signal of the primary cooling system, an air speed signal of the secondary cooling system and a battery temperature signal, outputting flow and air volume control signals and ensuring that the battery works within a reasonable temperature range;
the primary cooling system is used for receiving the flow control signal from the temperature control system and outputting coolant to the cooling system and comprises a coolant tank, a first water pump, a flow stop valve, a flow regulating valve and a flow meter;
the secondary cooling system is used for receiving an air volume control signal from the temperature control system and outputting cooling air volume to the cooling system, and comprises a compressor, an stratospheric condenser, an expansion valve, an evaporator, an air inlet fan and an air valve;
the cooling system is used for cooling the battery pack, discharging evaporated high-temperature coolant gas and monitoring the temperature of the battery in real time, and comprises a spray box, an atomizing nozzle, a temperature sensor, the battery pack and a heat-conducting silica gel sheet;
the condensation system is used for condensing high-temperature coolant gas evaporated by the cooling system and conveying the high-temperature coolant gas to the primary cooling system and comprises a condenser and a second water pump;
furthermore, the coolant tank is made of aluminum alloy and used for storing coolant, and is connected with the first water pump and the second water pump through copper pipes; the coolant is of a glycol type; the first water pump and the second water pump are used for circulating the coolant, and a water pump for a supercharged vehicle is adopted; the flow stop valve is an electronic control flow stop valve and is used for emergently closing the coolant; the flow regulating valve adopts a pneumatic angle seat valve and is used for regulating the coolant flow of an atomizing nozzle in the atomizing box; the flow meter adopts an impeller type flow meter and is used for recording the flow of the coolant.
Further, the compressor adopts a scroll compressor and is used for compressing the refrigerant and pushing the refrigerant to circulate in the system; the stratospheric condenser is a parallel flow condenser and is used for condensing high-temperature and high-pressure refrigerant gas compressed by the compressor; the expansion valve is used for adjusting the pressure ratio of the outlet of the condenser to the inlet of the evaporator to ensure that the secondary cooling system obtains high efficiency; the evaporator adopts a laminated evaporator and is provided with a PTC electric heating device and is used for evaporating the liquid refrigerant condensed by the condenser to a complete gas state; the fan is a cross flow fan and is used for conveying the cold energy on the surface of the evaporator into the compartment and the cooling system to cool the battery pack; the air volume valve adopts a miniature electromagnetic air valve and is used for controlling the air volume entering the cooling system and ensuring that the battery pack is in the optimal working temperature range.
Furthermore, the atomizing box is made of a soluble Polytetrafluoroethylene (PFA) corrosion-resistant material and used for fixing the atomizing nozzle and the battery pack, pipe orifices are formed in the left side and the right side of the atomizing box and connected with the primary cooling system through copper pipes, a plastic hose is connected with the secondary cooling system, and the nozzle is installed in a liquid feeding groove of the primary cooling system and welded on the surface of an upper shell of the atomizing box; the atomizing nozzle is a conical atomizing nozzle and is used for atomizing the coolant output by the primary cooling system and directly cooling the heat-conducting silica gel sheet of the battery pack in a liquid state; the temperature sensor adopts a thermocouple sensor and is used for detecting the temperature of the battery pack in the battery pack; the battery package is used for fixed group battery, adopts waterproof ventilated membrane material, includes: the left side of the upper shell, the lower shell, the battery pack, the copper plate and the fan is provided with an air inlet of the secondary cooling system, and the right side of the upper shell is provided with an air outlet for directly discharging gas; the battery pack is a blade battery module and is packaged in a battery pack in a parallel connection mode, the battery pack transfers heat to the heat-conducting silicon rubber sheet through the copper plate, and the positive electrode and the negative electrode of the battery pack adopt a silicon rubber foam sealing strip technology, so that the water inlet short circuit of the battery pack is effectively prevented; the air cavities distributed among the battery packs can effectively balance the air cooling effect of the battery packs at different positions.
Furthermore, a condenser of the condensing system adopts a stratospheric condenser and is used for condensing high-temperature coolant gas evaporated by the cooling battery pack in the cooling system; and the second water pump is used for conveying the condensed liquid coolant to the primary cooling system and is connected with a coolant tank in the primary cooling system through a copper pipe.
Compared with the prior art, the utility model provides a pair of multistage cooling type battery package has following advantage:
1) the battery pack is packaged in the spraying box in a form of a battery pack, and the battery pack transfers heat to the heat-conducting silica gel sheet through the copper plate, so that the problem of water inlet short circuit of the battery pack is effectively solved.
2) The temperature control system is additionally arranged, the working temperature and the heating rate of the battery pack are monitored in real time, different cooling schemes are implemented according to different temperature ranges, the power consumption of the cooling system is reduced, and the driving range of the electric automobile with the sexual energy is increased.
Drawings
FIG. 1 is a flow chart of the present invention;
FIG. 2 is a diagram of the structure of the battery pack and the secondary cooling system of the present invention;
FIG. 3 is a pipeline structure diagram of the multi-stage cooling system of the spray box of the present invention;
in the figure: 1. the device comprises a cooling agent box, 2, a first water pump, 3, a flow regulating valve, 4, a flow stop valve, 5, a flow meter, 6, an air valve, 7, an evaporator, 8, an expansion valve, 9, an air inlet fan, 10, an stratospheric condenser, 11, a compressor, 12, a spray nozzle, 13, a spray box, 14, a temperature sensor, 15, a heat-conducting silica gel sheet, 16, a battery pack, 17, an S-type condenser, 18, a second water pump, 19, an upper shell, 20, a lower shell, 21, a battery pack, 22, a copper plate, 23, a fan and 24, and a liquid feeding tank.
Detailed Description
The present invention will be further described with reference to the flow chart.
Fig. 1 shows the general flow diagram of the control system of the present invention, a multistage cooling battery pack device and a control method thereof, which includes a temperature control system, a first stage cooling system, a second stage cooling system, a cooling system and a condensing system.
Specifically, the temperature control system needs to adjust the opening of an air valve in real time to control the cooling air volume, firstly detects the working real-time temperature of the battery pack through a temperature sensor 14, is used for receiving a coolant flow signal of a primary cooling system, an air speed signal of a secondary cooling system and a battery temperature signal, outputs a flow and air volume control signal and ensures that the temperature of the battery pack is in the optimal working range
Specifically, the primary cooling system comprises a coolant tank 1, a first water pump 2, a flow regulating valve 3, a flow stop valve 4 and a flow meter 5; firstly, a temperature sensor 14 detects the real-time working temperature of the battery pack, and when the temperature of the battery pack is below 30 ℃, a primary cooling system does not work; when the temperature of the battery pack is above 30 ℃, the primary cooling system starts to work. First, the flow stop valve 4 is opened and the first water pump 2 is started to draw the coolant from the coolant tank 1, and the coolant flows through the flow control valve 3 and the flow stop valve 4 in this order, and flows into the spray nozzle 12 along the pipe groove after being adjusted by the flow meter 5.
Specifically, the secondary cooling system includes a compressor 11, a stratospheric condenser 10, an expansion valve 8, an evaporator 7, an air intake fan 9, and an air damper 6. Firstly, the temperature sensor 14 detects the real-time working temperature of the battery pack, and when the temperature of the battery pack is above 20 ℃, the secondary cooling system starts to work. The compressor 11 sucks low-temperature and low-pressure gas, the piston is driven to compress the gas through the operation of the motor, the refrigerant is compressed into high-pressure and high-temperature gas and discharged to the stratospheric condenser 10, the stratospheric condenser 10 can continuously dissipate heat in the process, the high-temperature and high-pressure gas is condensed into saturated liquid, and the expansion valve 8 blocks the flow of the refrigerant, so that a high-pressure region and a low-pressure region are generated in a cooling system, and the refrigeration cycle is ensured to be carried out. The liquid flows into the evaporator 7 through the expansion valve 8, the evaporator 7 is used as a heat exchanger, the high-pressure liquid refrigerant enters the evaporator 7 through the expansion valve 8, the liquid refrigerant is changed into fog due to the atomization effect of the expansion valve 8, and the fog refrigerant is changed into gas under the low-pressure condition. By utilizing the principle of evaporation and heat absorption, ambient heat is absorbed, and frost is formed near the evaporator 7, so that the surface temperature of the evaporator 7 is low at the moment, and cold air flowing through the surface of the evaporator is blown into the battery pack cooling chamber through the air inlet fan 9.
Specifically, the cooling system comprises a spray box 13, an atomizing nozzle 12, a temperature sensor 14, a battery pack 16 and a heat-conducting silicon sheet 15. Firstly, the temperature sensor 14 detects the real-time temperature of the battery pack operation, and when the temperature of the battery pack is above 20 ℃, the cooling system starts to operate. Further, when the temperature of the battery pack is between 20 ℃ and 30 ℃, the temperature control system outputs a wind speed control signal to the secondary cooling system, low-temperature gas is blown into the battery pack along the air inlet pipeline through the air inlet fan 9, the temperature of the battery pack is reduced, and the battery pack is discharged outdoors through the air outlet pipeline; when the temperature of the battery pack is above 30 ℃, the temperature control system outputs flow and air volume control signals at the same time, and the opening of the air valve needs to be adjusted in real time to control the cooling air volume. The nozzle 12 sprays atomized coolant on the heat-conducting silica gel sheet 15, the battery pack heat guided out by the cooling copper plate reduces the temperature of the battery pack by utilizing the principle of evaporation and heat absorption. Subsequently, the evaporated high-temperature coolant gas is discharged into the condensing system through the intake fan 9.
Specifically, the condensing system includes an S-type condenser 17 and a second water pump 18. And the coolant after sufficient heat exchange is recycled to the condensing system through a discharge pipeline of the secondary cooling system in the spray box. The S-shaped condenser 17 in the condensing system continuously dissipates heat, and after the heat in the coolant is absorbed, the heat-dissipated coolant is driven by the second water pump 18 to flow into the coolant tank 1, so that the cooling process of the battery pack is completed.
The utility model detects the real-time temperature of the battery pack through the temperature sensor, and when the temperature of the battery is lower than 20 ℃, the cooling system does not work;
when the temperature of the battery pack is between 20 ℃ and 30 ℃, the temperature control system outputs a wind speed control signal to a secondary cooling system, the secondary cooling system starts to work, a compressor compresses a refrigerant into high-pressure and high-temperature gas to be discharged to a stratosphere condenser, the high-pressure and high-temperature gas is condensed into saturated liquid, the saturated liquid flows into an evaporator through an expansion valve, the ambient heat is absorbed by utilizing the evaporation heat absorption principle, the vicinity of the evaporator is frosted, a low-temperature environment occurs, the low-temperature gas is blown into a battery pack along a pipeline through an air inlet fan, the temperature of the battery pack is reduced, the temperature of the battery pack is monitored by the temperature control system in real time, the opening degree of an air valve is adjusted in real time according to needs, the cooling air quantity is controlled, and the temperature of the battery pack is ensured to be within the optimal working range;
when the temperature of the battery pack is above 30 ℃, the temperature control system outputs flow and air volume control signals to the primary cooling system and the secondary cooling system respectively, the primary cooling system firstly opens a flow stop valve, starts a first water pump, extracts the coolant from a coolant tank and flows to a nozzle, the nozzle sprays the atomized coolant on a heat-conducting silica gel sheet, the cooling copper sheet guides out the heat of the battery pack, and the temperature of the battery pack is reduced; then, discharging the evaporated high-temperature coolant gas into a condensation system through a fan, and condensing by using an S-shaped condenser; finally, the condensed coolant liquid is conveyed to the primary cooling system again through a second water pump; meanwhile, the air inlet fan of the secondary cooling system blows low-temperature gas into the battery pack along the pipeline, and the temperature of the battery pack is further reduced.
The temperature control system monitors the temperature of the battery pack in real time, adjusts the opening degrees of the flow regulating valve and the air valve in real time according to needs, controls the flow of the nozzle and the cooling air quantity, and works simultaneously through two cooling modes, so that the temperature of the battery pack is rapidly reduced, safety accidents are avoided, and the temperature of the battery pack is ensured to be within the optimal working range; when the temperature of the battery pack is lower than 30 ℃, the flow stop valve is closed, the primary cooling system stops working, and the secondary cooling system is kept to work independently, so that the temperature of the battery pack is ensured to be in the optimal working range.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (8)
1. A multi-stage cooling type battery pack is characterized by comprising a temperature control system, a primary cooling system, a secondary cooling system and a cooling system; the cooling system is internally provided with a battery pack (16) and a temperature sensor (14) for sensing the temperature of the battery pack; the primary cooling system is used for receiving a flow control signal from the temperature control system and outputting coolant to the cooling system; the secondary cooling system is used for receiving an air volume control signal from the temperature control system and outputting cooling air volume to the cooling system; the temperature control system is used for receiving a coolant flow signal of the primary cooling system, an air speed signal of the secondary cooling system and a temperature signal of the temperature sensor, outputting a flow control signal to the primary cooling system and an air volume control signal to the secondary cooling system, and ensuring that the battery works within a reasonable temperature range.
2. The multi-stage cooling type battery pack according to claim 1, further comprising a condensing system for supplying a high-temperature coolant gas condensed and evaporated by the cooling system to the primary cooling system.
3. The multistage cooling type battery pack according to claim 2, wherein the primary cooling system comprises a coolant tank (1), a first water pump (2), a flow stop valve (3), a flow control valve (4) and a flow meter (5), the coolant tank is connected with the first water pump through a copper pipe, the first water pump is connected with the cooling system through a copper pipe, and the flow stop valve, the flow control valve and the flow meter are arranged between the first water pump and the cooling system.
4. The multistage cooling type battery pack according to claim 3, wherein the two-stage cooling system comprises a compressor (11), a stratospheric condenser (10), an expansion valve (8), an evaporator (7), an air inlet fan (9), and an air valve (6); the compressor is used for compressing the refrigerant, the condenser is used for condensing the compressed refrigerant gas, and the expansion valve is used for adjusting the pressure ratio of the outlet of the stratosphere condenser to the inlet of the evaporator; the evaporator is used for evaporating the liquid refrigerant condensed by the condenser to a complete gas state; the fan is used for conveying cold on the surface of the evaporator into a compartment and the cooling system to cool the battery pack.
5. The multistage cooling type battery pack according to claim 4, wherein the cooling system further comprises a spraying box (13), an atomizing nozzle (12) and a heat-conducting silicone sheet (15), the heat-conducting silicone sheet is installed on the top of the battery pack and used for guiding out the heat of the battery pack, and the atomizing nozzle is connected with the primary cooling system, arranged on the top of the inner side of the spraying box and located above the heat-conducting silicone sheet and used for performing direct liquid cooling on the heat-conducting silicone sheet.
6. The multi-stage cooling type battery pack according to claim 5, wherein the spray box is provided with nozzles at left and right sides, and is connected with the primary cooling system through a copper pipe, and is connected with the secondary cooling system through a plastic hose.
7. The multistage cooling type battery pack according to claim 6, wherein the battery pack comprises an upper shell (19), a lower shell (20), a battery pack (21), a copper plate (22) and a fan (23), wherein the battery pack is arranged in the upper shell and the lower shell, the left side of the battery pack is provided with an air inlet of the secondary cooling system, the right side of the battery pack is provided with an air outlet, and the fan is arranged at the air inlet; the battery pack is a blade battery module and is packaged in a battery pack in a parallel connection mode, and the battery pack transfers heat to the heat-conducting silica gel sheet through the copper plate.
8. The multi-stage cooling type battery pack according to claim 7, wherein the condensing system comprises an S-shaped condenser (17) and a second water pump (18), and the S-shaped condenser is connected with the coolant tank of the primary cooling system through the second water pump.
Priority Applications (1)
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CN202120158524.9U CN214176110U (en) | 2021-01-21 | 2021-01-21 | Multistage cooling type battery pack |
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CN202120158524.9U CN214176110U (en) | 2021-01-21 | 2021-01-21 | Multistage cooling type battery pack |
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CN214176110U true CN214176110U (en) | 2021-09-10 |
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CN202120158524.9U Active CN214176110U (en) | 2021-01-21 | 2021-01-21 | Multistage cooling type battery pack |
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2021
- 2021-01-21 CN CN202120158524.9U patent/CN214176110U/en active Active
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