A battery thermal management system and its thermal management method

Abstract

The present invention discloses a battery thermal management system and its thermal management method, which relates to the field of automotive battery management equipment, and includes: a battery module and an intelligent control module. The battery module includes several rows of battery packs stacked on top of each other. A sensor for detecting whether a battery undergoes thermal runaway is provided on the battery pack. A telescopic rod for controlling the distance between adjacent battery packs is provided between adjacent battery packs. Both the sensor and the telescopic rod are electrically connected to the intelligent control module. In the present invention, when a battery undergoes thermal runaway, the sensor transmits a signal of thermal runaway to the intelligent control module. After receiving the information of thermal runaway, the intelligent control module controls the telescopic rod to extend to increase the distance between adjacent battery packs, so that the adjacent battery packs are separated by air, preventing the heat transfer between the battery pack with thermal runaway and other battery packs, prolonging the spread time of thermal runaway of the battery module, and winning precious escape time and rescue time for the driver.

Description

Technical Field

[0001] The present invention relates to the field of automotive battery management equipment, and particularly to a battery thermal management system and a thermal management method thereof. Background Art

[0002] New energy vehicles have developed rapidly. Lithium-ion batteries are widely used in hybrid vehicles and electric vehicles due to their advantages such as light weight, long service life, no memory effect, high density, and high specific power. To avoid negative impacts such as reduced lifespan, performance loss, thermal runaway, and even explosion during the charging and discharging process of lithium-ion batteries, it is crucial to establish an effective thermal management system for lithium-ion battery packs. In the past decade, organic phase change materials have been widely used in battery thermal management systems due to their high latent heat, wide application temperature range, and low production cost. Combining phase change materials with a liquid cooling system can achieve good thermal management effects. For example, the invention patent with the application number "202010173044.X" and the name "A Passive Phase Change Material Temperature Regulation System for Power Batteries" discloses a battery temperature management system that combines phase change materials with a liquid cooling system. Although it can cool the battery, when thermal runaway occurs in a battery, the heat of the battery will quickly transfer to other batteries through the phase change material, causing the temperature of other batteries to rise and increasing the risk of thermal runaway in other batteries.

[0003] Therefore, there is an urgent need for a battery thermal management system that can prevent heat transfer between a battery pack in thermal runaway and other battery packs and extend the spread time of thermal runaway in the battery module. Summary of the Invention

[0004] The purpose of the present invention is to provide a battery thermal management system and a thermal management method thereof to solve the problems existing in the above-mentioned prior art. By setting sensors to detect whether the battery is in thermal runaway, when thermal runaway occurs in the battery, the intelligent control module controls the telescopic rod to extend to increase the distance between adjacent battery packs, preventing heat transfer between the battery pack in thermal runaway and other battery packs and extending the spread time of thermal runaway in the battery module.

[0005] To achieve the above purpose, the present invention provides the following solution: The present invention provides a battery thermal management system, including a battery module and an intelligent control module. The battery module includes several rows of battery packs stacked on top of each other. A sensor for detecting whether the battery is in thermal runaway is provided on the battery pack. A telescopic rod for controlling the distance between adjacent battery packs is provided between adjacent battery packs. Both the sensor and the telescopic rod are electrically connected to the intelligent control module. When the sensor detects that the battery is in thermal runaway, the intelligent control module controls the telescopic rod to extend to increase the distance between adjacent battery packs.

[0006] Preferably, a support bar is provided at an end of the battery pack in the extending direction, the support bar is parallel to the axis of the battery in the battery pack, and the telescopic rod is disposed between adjacent support bars.

[0007] Preferably, a heat dissipation cylinder for dissipating heat from the battery is wrapped around the outer wall of the battery of the battery pack, and the support bar is provided at an end of the heat dissipation cylinder in the extending direction of the battery pack.

[0008] Preferably, the heat dissipation cylinder includes a first connecting plate and a second connecting plate. The first connecting plate and the second connecting plate protrude outward at positions corresponding to the batteries of the battery pack to form grooves, and connecting bars are provided at ends in the extending direction of the battery pack. The connecting bars of the first connecting plate and the second connecting plate are connected to each other to form the support bar, and an accommodation space for placing the battery is formed between the relative grooves of the first connecting plate and the second connecting plate.

[0009] Preferably, the battery thermal management system further includes a chiller, the chiller includes a cold water circulation module and a serpentine heat exchange tube. A strip-shaped through hole is formed in the middle of the support bar, and the straight sections of the serpentine heat exchange tube are respectively connected to a plurality of the strip-shaped through holes on the same side of the battery pack. The material of the bent section of the serpentine heat exchange tube is rubber that can be elastically deformed.

[0010] Preferably, bending portions are provided at both ends of the heat dissipation cylinder along the battery axis direction, the free ends of the bending portions are hermetically connected to the battery, a closed space is formed between the heat dissipation cylinder and the outer wall of the battery of the battery pack, and a phase change material is filled in the closed space.

[0011] Preferably, temperature sensors are provided on both sides and in the middle of the battery pack, the temperature sensors are electrically connected to the intelligent control module, and the intelligent control module is electrically connected to the cold water circulation module.

[0012] Preferably, the cold water circulation module includes a water pump with adjustable power, a water storage tank and a refrigerator. The water storage tank is communicated with the water inlet of the serpentine heat exchange tube through the water pump, and the water outlet of the serpentine heat exchange tube is connected to the water storage tank through the refrigerator. The water pump is electrically connected to the intelligent control module.

[0013] Preferably, heat insulation layers are provided outside the communication pipelines between the water storage tank, the water pump, the serpentine heat exchange tube and the refrigerator.

[0014] The present invention also provides a thermal management method for the above battery thermal management system, including the following steps:

[0015] S1: When the sensor detects that the battery is in thermal runaway, the sensor transmits the signal to the intelligent control module. The intelligent control module controls the telescopic rod to extend and retract, adjusts the distance between adjacent battery packs, prevents heat transfer between the batteries, and extends the thermal runaway spread time of the battery module.

[0016] S2: When the battery is operating normally, the temperature generated by the battery is absorbed by the phase change material, and the phase change material absorbs heat and gradually changes from a solid state to a liquid state.

[0017] S3: The temperature sensor continuously detects the temperature of the battery pack. When the temperature is sufficient to completely melt the phase change material, the intelligent control module controls the water pump to start, supplies cold water into the serpentine heat exchange tube, and the cold water cools the internal phase change material through the heat dissipation cylinder.

[0018] S4: The intelligent control module adjusts the power of the water pump in real time according to the temperature change, and keeps the phase change material in the melting state all the time.

[0019] The present invention has achieved the following technical effects over the prior art:

[0020] 1. In the present invention, a sensor is provided to detect whether the battery is in thermal runaway. When the battery is in thermal runaway, the sensor transmits the signal of thermal runaway to the intelligent control module. After receiving the information of thermal runaway, the intelligent control module controls the telescopic rod to extend and increase the distance between adjacent battery packs, so that the adjacent battery packs are separated by air, preventing the heat transfer between the battery pack in thermal runaway and other battery packs, and extending the thermal runaway spread time of the battery module, thus winning precious escape time and rescue time for the driver.

[0021] 2. In the present invention, the intelligent control module can control the power of the water pump in real time. When the ambient temperature is low, the phase change material can meet the heat dissipation requirements, and the liquid cooling is turned off to avoid unnecessary energy consumption and play an energy-saving role. When the ambient temperature is high, the phase change material cannot meet the heat dissipation requirements, and the liquid cooling is started.

[0022] 3. The setting of the support bar in the present invention not only meets the setting requirements of the telescopic rod, but also the strip-shaped through holes provided therein can meet the setting requirements of the serpentine heat exchange tube, effectively saving the space required for the layout of the telescopic rod and the serpentine heat exchange tube, and improving the space utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1It is a schematic structural diagram of the battery thermal management system of the present invention;

[0025] Figure 2 It is a system schematic diagram of the battery thermal management system of the present invention;

[0026] Among them, 1. Battery module; 2. Intelligent control module; 3. Battery pack; 4. Sensor; 5. Telescopic rod; 6. Support bar; 7. Heat dissipation cylinder; 8. Serpentine heat exchange tube; 9. Temperature sensor; 10. Water pump; 11. Water storage tank; 12. Refrigerator; 13. Shunt; 14. Flow meter. Specific embodiments

[0027] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0028] The purpose of the present invention is to provide a battery thermal management system and its thermal management method to solve the problems existing in the prior art. By setting sensors to detect whether the battery is thermally out of control, when the battery is thermally out of control, the telescopic rod is controlled to extend by the intelligent control module to increase the distance between adjacent battery packs, preventing the heat transfer between the battery pack with thermal runaway and other battery packs, and prolonging the spread time of the thermal runaway of the battery module.

[0029] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0030] Please refer to as Figures 1-2 As shown, a battery thermal management system is provided, including a battery module 1 and an intelligent control module 2. The battery module 1 includes several rows of battery packs 3 stacked on top of each other. A sensor 4 is provided on the battery pack 3. The sensor 4 is used to detect whether the battery is thermally out of control. A telescopic rod 5 and a sensor 4 are provided between adjacent battery packs 3. The telescopic rod 5 is used to control the distance between adjacent battery packs 3. Both the sensor 4 and the telescopic rod 5 are electrically connected to the intelligent control module 2. When the sensor 4 detects that the battery is thermally out of control, the intelligent control module 2 controls the telescopic rod 5 to extend to increase the distance between adjacent battery packs 3. The sensor 4 can be a flame sensor, a voltage sensor, a temperature sensor, or a gas sensor. Since a fire will occur when the battery is thermally out of control, the flame sensor mainly judges whether the battery is thermally out of control by detecting whether there is a flame; since the voltage and temperature of the battery will change when the battery is thermally out of control, the voltage and temperature data of the battery can be detected by the voltage sensor and the temperature sensor to analyze whether the battery is thermally out of control; since the battery will release H before thermal runaway2 and various alkanes, so it is possible to detect whether there is H 2 or the generation of various alkanes to determine whether the battery has thermal runaway.

[0031] A sensor 4 is provided at each battery in the battery pack 3 to monitor whether each battery has thermal runaway.

[0032] In order to save energy, when it is detected that a certain battery pack 3 has thermal runaway, the intelligent control system only needs to control the telescopic rod 5 between the battery pack 3 with thermal runaway and its adjacent battery pack 3 to extend.

[0033] In order to adapt to the vehicle body, the distance between two battery packs 3 separated by the telescopic rod 5 is 0.2 cm - 2 cm, and a telescopic space is reserved during the installation of the battery module.

[0034] A support bar 6 is provided at the end of the battery pack 3 in the extending direction. The support bar 6 is parallel to the axis of the battery in the battery pack 3, and the thickness of the support bar 6 is less than the diameter of the battery. The telescopic rod 5 is arranged between adjacent support bars 6. Compared with the telescopic rod 5 being arranged between the batteries in the battery pack 3, in the vertical direction, a part of the telescopic rod 5 coincides with the space occupied by the battery, which can effectively reduce the space occupied by the overall device in height and improve the space occupancy rate of the device.

[0035] Support bars 6 are provided at both ends of the battery pack 3 in the extending direction to improve the stability of the telescopic movement.

[0036] The outer peripheral wall of the battery in the battery pack 3 is wrapped with a heat dissipation cylinder 7 for dissipating heat from the battery. A support bar 6 is provided at the end of the heat dissipation cylinder 7 in the extending direction of the battery pack 3. The support bar 6 is integrally provided with the heat dissipation cylinder 7, and the material of both is copper.

[0037] In the non-extended state of the telescopic rod 5, adjacent heat dissipation cylinders 7 are in contact. When a certain battery pack 3 has a higher temperature, the heat can be transferred to the heat dissipation cylinders 7 of other battery packs 3 for heat dissipation.

[0038] The heat dissipation cylinder 7 includes a first connecting plate and a second connecting plate. The first connecting plate and the second connecting plate protrude outward corresponding to the position of the battery in the battery pack 3 to form a groove. The bottom end of the groove is arc-shaped, and a connecting bar is provided at the end in the extending direction of the battery pack 3. The connecting bars of the first connecting plate and the second connecting plate are connected to each other to form a support bar 6. The connection method can be bolt connection, which is convenient for installation and disassembly. A placement space for the battery is formed between the relative grooves of the first connecting plate and the second connecting plate. In this structure, when adjacent heat dissipation cylinders 7 are in contact, it is actually a line contact, which increases the contact area between the heat dissipation cylinder 7 and the air, improves the heat dissipation effect, and several empty areas will be formed between adjacent heat dissipation cylinders 7. The sensor 4 can be arranged in the empty areas, effectively utilizing the space of the empty areas and improving the space utilization rate.

[0039] The battery thermal management system further includes a chiller, which includes a cold water circulation module and a serpentine heat exchange tube 8. A strip-shaped through hole is formed in the middle of the support bar 6. The straight sections of the serpentine heat exchange tube 8 are respectively connected to a plurality of strip-shaped through holes on the same side of the battery pack 3. The bending section of the serpentine heat exchange tube 8 is made of rubber that can be elastically deformed. The cold water in the serpentine heat exchange tube 8 can cool the heat dissipation cylinder 7, improving the cooling effect on the battery.

[0040] The setting of the support bar 6 not only meets the setting requirements of the telescopic rod 5, but also the strip-shaped through holes provided therein can meet the setting requirements of the serpentine heat exchange tube 8, effectively saving the space required for the layout of the telescopic rod 5 and the serpentine heat exchange tube 8 and improving the space utilization rate.

[0041] Bending portions are provided at both ends of the heat dissipation cylinder 7 along the battery axis direction. The free ends of the bending portions are hermetically connected to the battery. The hermetic connection method is to provide a sealing ring at the free ends of the bending portions. A closed space is formed between the heat dissipation cylinder 7 and the outer wall of the battery of the battery pack 3. A phase change material is filled in the closed space. The phase change material absorbs the temperature generated during the operation of the battery through its own characteristics and dissipates its own heat through the heat dissipation cylinder 7. At the same time, when the external temperature is relatively high, the cold water circulation module can be turned on. At this time, the cold water in the serpentine heat exchange tube 8 will also absorb the heat of the phase change material.

[0042] The specific control structure for turning on the cold water circulation module is as follows: Temperature sensors 9 are provided on both sides and in the middle of the battery pack 3. The temperature sensors 9 can be provided outside or inside the heat dissipation cylinder 7. The temperature sensors 9 are electrically connected to the intelligent control module 2, and the intelligent control module 2 is electrically connected to the cold water circulation module. Since serpentine heat exchange tubes 8 are provided on both sides of the battery pack 3, the middle is a high-temperature area and the two sides are low-temperature areas. The temperature sensors 9 detect the highest temperature and the maximum temperature difference of the battery pack 3 and transmit the temperature signals to the intelligent control module 2. The intelligent control module 2 controls the start of the cold water circulation module according to the temperature signals.

[0043] A flow divider 13 is provided between the cold water circulation module and the serpentine heat exchange tube 8 to make the cold water flow evenly into different serpentine heat exchange tubes 8, ensuring the same liquid cooling efficiency.

[0044] A flow meter 14 is provided at the water outlet of the serpentine heat exchange tube 8, and whether the serpentine heat exchange tube 8 is blocked can be judged by the change in flow rate.

[0045] The cold water circulation module includes a water pump 10 with adjustable power, a water storage tank 11, and a cooler 12. The water storage tank 11 is connected to the water inlet of the serpentine heat exchange tube 8 through the water pump 10, and the water outlet of the serpentine heat exchange tube 8 is connected to the water storage tank 11 through the cooler 12. The water pump 10 is electrically connected to the intelligent control module 2. The intelligent control module 2 controls the power of the water pump 10 according to the temperature information of the temperature sensor 9. When the ambient temperature is relatively low, the phase change material can meet the heat dissipation requirements, and the temperature detected by the temperature sensor 9 will not be too high. At this time, the liquid cooling is turned off to avoid unnecessary energy consumption and play an energy-saving role. When the ambient temperature is relatively high, the phase change material cannot meet the heat dissipation requirements, and the temperature detected by the temperature sensor 9 continues to rise. At this time, the liquid cooling is started.

[0046] Insulation layers are provided outside the connecting pipelines among the water storage tank 11, the water pump 10, the serpentine heat exchange tube 8, and the cooler 12 to prevent heat exchange between the cold water and the external environment and reduce energy loss.

[0047] The present invention also provides a thermal management method for the above battery thermal management system, including the following steps:

[0048] S1: When the sensor 4 detects that a battery has a thermal runaway, the sensor 4 transmits a signal to the intelligent control module 2. The intelligent control module 2 controls the telescopic rod 5 to expand and contract, adjusts the distance between adjacent battery packs 3, and prevents heat transfer between the battery with thermal runaway and the batteries in other non-runaway battery packs 3, thereby prolonging the thermal runaway spread time of the battery module 1;

[0049] S2: When the battery is operating normally, the temperature generated by the battery is absorbed by the phase change material. The phase change material absorbs heat and gradually changes from a solid state to a liquid state, and dissipates heat to the outside through the heat dissipation cylinder 7;

[0050] S3: The temperature sensor 9 continuously detects the temperature of the battery pack 3. When the ambient temperature is relatively low, the phase change material can timely dissipate the internal heat, and the temperature will not be higher than the temperature when the phase change material is completely melted. At this time, the water pump 10 is turned off to save energy. When the ambient temperature is relatively high, the phase change material cannot timely dissipate the internal heat, which will cause the temperature of the battery pack 3 to gradually rise. When the temperature is sufficient to completely melt the phase change material, the intelligent control module 2 controls the water pump 10 to start, and supplies cold water into the serpentine heat exchange tube 8. The cold water cools the internal phase change material through the heat dissipation cylinder 7;

[0051] S4: When using cold water to cool the phase change material, the intelligent control module 2 adjusts the power of the water pump 10 in real time according to the temperature change. The power of the water pump 10 is proportional to the temperature, and keeps the phase change material in a melting state all the time.

[0052] Adaptations made according to actual needs are all within the protection scope of the present invention.

[0053] It should be noted that for those skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be construed as limiting the claims involved.

[0054] Specific examples are used in the present invention to illustrate the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. At the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A battery thermal management system, characterized in that, it includes a battery module and an intelligent control module. The battery module includes several rows of stacked battery packs. A sensor for detecting whether a battery undergoes thermal runaway is provided on the battery pack. A telescopic rod for controlling the distance between adjacent battery packs is provided between adjacent battery packs. Both the sensor and the telescopic rod are electrically connected to the intelligent control module. When the sensor detects that a battery undergoes thermal runaway, the intelligent control module controls the telescopic rod to extend to increase the distance between adjacent battery packs; when it is detected that a certain battery pack undergoes thermal runaway, only the telescopic rod between the battery pack with thermal runaway and its adjacent battery pack needs to be controlled to extend; Support bars are provided at the ends of the battery pack in the extending direction, and the support bars are parallel to the axes of the batteries in the battery pack. The telescopic rods are arranged between adjacent support bars; The battery thermal management system further includes a chiller, which includes a cold water circulation module and a serpentine heat exchange tube. A strip-shaped through hole is opened in the middle of the support bar, and the straight sections of the serpentine heat exchange tube are respectively connected to several strip-shaped through holes on the same side of the battery pack.

2. The battery thermal management system according to claim 1, characterized in that, a heat dissipation cylinder for dissipating heat from the battery is wrapped outside the peripheral wall of the battery of the battery pack, and the support bar is provided at the end of the heat dissipation cylinder in the extending direction of the battery pack.

3. The battery thermal management system according to claim 2, characterized in that, the heat dissipation cylinder includes a first connecting plate and a second connecting plate. The first connecting plate and the second connecting plate protrude outward corresponding to the positions of the batteries of the battery pack to form grooves, and connecting bars are provided at the ends in the extending direction of the battery pack. The connecting bars of the first connecting plate and the second connecting plate are connected to each other to form the support bar, and an accommodation space for placing the battery is formed between the relative grooves of the first connecting plate and the second connecting plate.

4. The battery thermal management system according to claim 1, characterized in that, the material of the bent section of the serpentine heat exchange tube is rubber that can be elastically deformed.

5. The battery thermal management system according to claim 2, characterized in that, bending portions are provided at both ends of the heat dissipation cylinder in the direction of the battery axis, and the free ends of the bending portions are hermetically connected to the battery. A closed space is formed between the heat dissipation cylinder and the outer wall of the battery of the battery pack, and a phase change material is filled in the closed space.

6. The battery thermal management system according to claim 5, characterized in that, temperature sensors are provided on both sides and in the middle of the battery pack. The temperature sensors are electrically connected to the intelligent control module, and the intelligent control module is electrically connected to the cold water circulation module.

7. The battery thermal management system according to claim 1, characterized in that, The cold water circulation module includes a water pump with adjustable power, a water storage tank, and a refrigerator. The water storage tank is communicated with the water inlet of the serpentine heat exchange tube through the water pump. The water outlet of the serpentine heat exchange tube is connected to the water storage tank through the refrigerator. The water pump is electrically connected to the intelligent control module.

8. The battery thermal management system according to claim 7, wherein, heat insulation layers are provided outside the communication pipelines among the water storage tank, the water pump, the serpentine heat exchange tube, and the refrigerator.

9. A thermal management method for a battery thermal management system, wherein, applying the battery thermal management system according to any one of claims 1-8, comprising the following steps: S1: When the sensor detects that the battery is in thermal runaway, the sensor transmits a signal to the intelligent control module. The intelligent control module controls the telescopic rod to expand and contract, adjusts the distance between adjacent battery packs, prevents heat transfer between the batteries, and extends the thermal runaway spread time of the battery module; S2: When the battery is working normally, the temperature generated by the battery is absorbed by the phase change material, and the phase change material absorbs heat and gradually changes from solid state to liquid state; S3: The temperature sensor continuously detects the temperature of the battery pack. When the temperature is sufficient to completely melt the phase change material, the intelligent control module controls the water pump to start, supplies cold water into the serpentine heat exchange tube, and the cold water cools the internal phase change material through the heat dissipation cylinder; S4: The intelligent control module adjusts the power of the water pump in real time according to the temperature change, and keeps the phase change material in the melting state all the time.

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