Battery pack heat dissipation method based on phase change material and heat dissipation pipe

Abstract

The invention discloses a battery pack heat dissipation method based on a phase change material and a heat dissipation pipe, and belongs to the technical field of battery packs, the battery pack comprises a shell and a plurality of battery packs arranged in the shell; the phase change material covers the outer part of the shell of the battery pack; the heat dissipation assembly is connected with the battery pack and is used for transferring heat of the battery pack to the outside; the control assembly is used for controlling the heat dissipation assembly to dissipate heat when the temperature of the battery pack reaches a preset range; the circulation loop comprises an internal channel and an external channel, and a built-in phase change material can be melted when the temperature of the battery rises, so that redundant heat is absorbed, and the temperature of the battery is reduced; the phase-change material is solidified, releases heat and keeps the temperature of the battery during cooling, so that the battery can reach a proper working temperature condition in a high-temperature or low-temperature working environment, a channel is arranged in the phase-change material, water in the internal channel is circulated by using a water pump, the heat of the phase-change material is reduced, then circulation is performed, and the cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of battery packs, and more specifically, to a battery pack heat dissipation method based on phase change materials and heat dissipation pipes. Background Art

[0002] A battery pack is a device that combines multiple battery cells or modules to form a device that can store and provide electrical energy. It is commonly used to power various devices, especially in the fields of electric vehicles (EV), hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), electric bicycles, power tools, and energy storage systems. The battery pack is composed of multiple battery cells (such as lithium-ion batteries, lead-acid batteries, nickel-metal hydride batteries, etc.) connected in series or in parallel to meet specific voltage and capacity requirements.

[0003] The prior art has a publication number of CN118117201A, which discloses a heat dissipation system and heat dissipation method for a battery pack. The heat dissipation system of the battery pack includes a first fan, a second fan, a battery pack, a control module and a temperature detection module; the first fan is arranged at the first end of the battery pack, and the second fan is arranged at the second end of the battery pack opposite to the first end. The air outlet directions of the first fan and the second fan are opposite and cannot be started at the same time; the temperature detection module is used to detect the battery temperature at at least two different positions inside the battery pack; the control module is used to obtain the battery temperature detected by the temperature detection module, determine the internal temperature difference of the battery pack based on the battery temperature, and control the opening and closing of the first fan and the second fan based on the battery temperature and the internal temperature difference, so that the internal temperature difference of the battery pack is within the preset temperature difference range. By adopting the above scheme, the problem that the existing heat dissipation scheme of the battery pack will cause the temperature difference inside the battery pack to increase, thereby making the consistency of the battery pack worse is solved.

[0004] Batteries provide power for electric vehicles and play a decisive role in the performance and driving range of electric vehicles. Lithium batteries have become the most promising candidate batteries to promote the development of electric vehicles due to their advantages such as high energy density and low self-discharge rate. However, lithium-ion batteries are very sensitive to operating temperature. On the one hand, when lithium batteries operate at higher temperatures (greater than 35°C), the side reactions in the battery will be aggravated, resulting in the runaway of battery temperature, which will in turn cause battery capacity decay and shortened life. Electric vehicles may cause fires due to battery overheating. Therefore, people are paying more and more attention to the safety of electric vehicles. On the other hand, when lithium batteries operate at lower temperatures (less than 15°C), their discharge capacity is greatly reduced due to increased internal resistance and suppressed reaction kinetics, resulting in a greatly shortened driving range of electric vehicles. In addition, the uneven temperature distribution of lithium batteries will lead to inconsistent electrochemical processes, further reducing the capacity of the battery pack and shortening the cycle life. Therefore, in order to ensure the safety and performance of lithium batteries in electric vehicles during operation, an efficient battery thermal management system (BTMS) is very necessary. With the continuous improvement of lithium battery technology, the persistent thermal and safety issues have become more serious, which puts higher requirements on the battery thermal management system. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies in the prior art, the present invention provides a battery pack heat dissipation method based on phase change materials and heat dissipation tubes, which solves the above-mentioned problems.

[0007] (II) Technical solution

[0008] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a battery pack heat dissipation method based on phase change material and heat dissipation pipe, comprising a battery pack,

[0009] A battery pack, comprising a housing and a plurality of battery packs disposed inside the housing;

[0010] Phase change material, which is wrapped around each battery group and filled in the battery pack;

[0011] A heat dissipation component, which is connected to the battery pack and is used to transfer the heat of the battery pack to the outside;

[0012] A control component, which is used to control the heat dissipation component to dissipate heat when the temperature of the battery pack reaches a predetermined range;

[0013] The circulation loop includes an inner channel and an outer channel.

[0014] Preferably, the heat dissipation component includes a built-in pipeline, water inside the pipeline, a water pump, a compressor and an expansion water tank, and the interior of the phase change material is provided with a built-in pipeline to form a circulating water circuit.

[0015] Preferably, one end of the built-in pipe is connected to a water pump, and the other end of the built-in pipe is connected to a compressor to form a water circulation loop, and the expansion water tank is connected to the water circulation loop to provide and store circulating water.

[0016] Preferably, the control component includes at least one temperature sensor arranged in the battery pack, and the temperature sensor is arranged in the battery pack to detect the temperature of the battery pack. The temperature sensor is connected to the water pump and the compressor to detect the temperature of the battery pack and control the start-up of the water pump and the compressor.

[0017] Preferably, a first interface and a second interface are provided on the shell of the battery pack, and the internal channel and the external channel are both provided between the first interface and the second interface for connecting the built-in pipeline to form a circulation loop.

[0018] Preferably, the circulation loop comprises an inner channel and an outer channel, and the outer channel is also arranged between the first interface and the second interface.

[0019] Preferably, the internal channel is used to connect built-in pipes to form a circulation loop, and the external channel is provided with a water pump and a compressor to accelerate water circulation.

[0020] Preferably, the phase change material includes materials such as fatty acids or paraffin, which will melt and absorb heat when heated to a certain temperature to reduce the battery temperature; when cooled, they will solidify and release heat to keep the battery temperature stable. The built-in pipes are arranged in a surrounding type inside the phase change material, and the water circulation is accelerated by a water pump to absorb the heat of the phase change material, thereby achieving the purpose of reducing the battery operating temperature.

[0021] Preferably, when the temperature sensor detects that the temperature of the battery pack exceeds a set threshold, the control component will start the water pump and the compressor to accelerate water circulation, and the phase change material and the water in the circulation pipe will jointly dissipate the heat of the battery pack.

[0022] Preferably, the cooling method includes heat dissipation at normal temperature and heat dissipation at high temperature. The heat dissipation at normal temperature refers to when the vehicle is working and the battery is at normal operating temperature, the phase change material alone is sufficient to meet the cooling needs of the battery. The heat dissipation at high temperature refers to when the entire vehicle is overcharged for a long time or the battery continuously outputs current for a long time, the phase change material cannot meet the heat dissipation of the battery pack, and the temperature sensor at the connection port senses that the temperature exceeds the threshold, and the water pump will start. The water pump accelerates the flow of water, which can help the phase change material and the battery to dissipate heat together, reducing the capacity attenuation of the battery due to long-term overcharging or prolonged output current and the risk of thermal runaway caused by excessive temperature.

[0023] (III) Beneficial effects

[0024] Compared with the prior art, the present invention provides a battery pack heat dissipation method based on phase change materials and heat dissipation pipes, which has the following beneficial effects:

[0025] 1. A battery pack heat dissipation method based on phase change materials and heat pipes. When the battery temperature rises, the built-in phase change material will melt, absorb excess heat, and lower the battery temperature; when cooled, it will solidify, release heat, and maintain the battery temperature, so that the battery can reach a suitable operating temperature condition in a high or low temperature working environment.

[0026] 2. This method of heat dissipation for a battery pack based on phase change materials and heat pipes, builds a channel inside the phase change material, uses a water pump to circulate water in the internal channel, reduces the heat of the phase change material, makes the phase change material less likely to be damaged under high temperature conditions, and makes the battery less likely to have thermal runaway at high temperatures. The temperature of the water in the internal pipe is then lowered by a compressor and then circulated, thereby reducing costs.

[0027] 3. This is a battery pack heat dissipation method based on phase change materials and heat pipes. By combining phase change materials (such as fatty acids or paraffin) and a circulating water heat dissipation system, this method can efficiently absorb and transfer the heat generated by the battery pack. The phase change process of the phase change material at a specific temperature can effectively reduce the battery temperature, and the circulating water can further accelerate the transfer and release of heat, ensuring the stability of the battery pack temperature and extending the battery life.

[0028] 4. A battery pack heat dissipation method based on phase change materials and heat pipes. The control component monitors the battery pack temperature in real time through a temperature sensor, and automatically starts the heat dissipation component when the temperature reaches or exceeds a predetermined threshold. This intelligent temperature control mechanism can accurately adjust the heat dissipation efficiency to avoid excessive or insufficient heat dissipation, thereby improving energy utilization efficiency and system stability. The design of the heat dissipation component and the circulation loop makes the entire heat dissipation system compact and easy to integrate into the battery pack. At the same time, the setting of the external channel facilitates the installation and maintenance of heat dissipation equipment, such as water pumps and compressors, reducing the complexity and maintenance cost of the system.

[0029] 5. This is a battery pack heat dissipation method based on phase change materials and heat pipes. Under extreme conditions such as high temperature, long-term overcharging, and continuous output current, the method can respond quickly and enhance the heat dissipation effect, effectively reducing the risk of thermal runaway caused by excessive temperature of the battery and improving the safety and reliability of the battery pack.

[0030] 6. This is a battery pack heat dissipation method based on phase change materials and heat pipes. Phase change materials are generally non-toxic and harmless and are easy to recycle and dispose of. In addition, the circulating water system reduces dependence on traditional coolants and reduces potential impacts on the environment, which is in line with the concept of sustainable development. By effectively managing the temperature of the battery pack, this method can reduce battery performance degradation caused by temperature fluctuations, extend the battery life, and improve the overall performance of electric vehicles and user satisfaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the external structure of the battery pack of the present invention;

[0032] Figure 2 It is a schematic diagram of the internal heat dissipation of the battery pack provided by the implementation of the present invention;

[0033] Figure 3 It is a battery thermal management principle diagram provided by the implementation of the present invention;

[0034] Figure 4 is a schematic diagram of a battery thermal management cycle provided by the present invention;

[0035] Figure 5 This is a diagram showing the effect of air cooling on battery temperature;

[0036] Figure 6 This is a diagram showing the effect of air cooling on battery temperature;

[0037] Figure 7 A diagram showing the effect of the cooling method of the present invention on the flow tube temperature;

[0038] Figure 8 This is a diagram showing the effect of the cooling method of the present invention on the battery connector temperature;

[0039] Fig. 9 This is a diagram showing the effect of the cooling method of the present invention on the battery temperature;

[0040] Fig.10 This is a diagram showing the effect of the cooling method of the present invention on the temperature of the phase change material.

[0041] In the figure: 1. battery pack; 2. phase change material; 3. heat dissipation component; 4. control component; 11. shell; 12. battery pack; 13. first interface; 14. second interface; 31. built-in pipe; 32. water inside the pipe; 33. water pump; 34. compressor; 41. temperature sensor; 5. circulation loop; 51. internal channel; 52. external channel. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] See also Figure 1-Figure 10 , the present invention provides a technical solution:

[0044] A battery pack heat dissipation method based on phase change material and heat dissipation pipe, comprising a battery pack 1,

[0045] A battery pack 1 includes a housing 11 and a plurality of battery packs 12 disposed inside the housing 11;

[0046] Phase change material 2, which is wrapped in each battery group 12 and filled in the battery pack 1;

[0047] A heat dissipation component 3, which is connected to the battery pack 1 and is used to transfer the heat of the battery pack 1 to the outside;

[0048] A control component 4, which is used to control the heat dissipation component 3 to dissipate heat when the temperature of the battery pack 1 reaches a predetermined range;

[0049] The circulation loop 5 includes an inner channel 51 and an outer channel 52 .

[0050] Furthermore, the heat dissipation component 3 includes a built-in pipe 31, water 32 inside the pipe, a water pump 33, a compressor 34 and an expansion water tank. The built-in pipe 31 is arranged inside the phase change material 2 to form a circulating water circuit.

[0051] Furthermore, one end of the built-in pipe 31 is connected to the water pump 33, and the other end of the built-in pipe 31 is connected to the compressor 34, forming a water circulation loop 5. The expansion water tank is connected to the water circulation loop 5 to provide and store circulating water. In order to ensure that the water in the circulation loop 5 can circulate continuously and stably, the expansion water tank is not only used to provide and store circulating water, but also equipped with water level monitoring and automatic water replenishment functions. When the water level is lower than the preset threshold, the system will automatically replenish water to an appropriate level, thereby avoiding a decrease in heat dissipation efficiency or system failure due to lack of water.

[0052] Furthermore, the control component 4 includes at least one temperature sensor 41 arranged in the battery pack 1. The temperature sensor 41 is arranged in the battery pack 1 for detecting the temperature of the battery pack 1. The temperature sensor 41 is connected to the water pump 33 and the compressor 34 for detecting the temperature of the battery pack 1 and controlling the start-up of the water pump 33 and the compressor 34.

[0053] Furthermore, a first interface 13 and a second interface 14 are provided on the shell 11 of the battery pack 1 , and an internal channel 51 and an external channel 52 are both provided between the first interface 13 and the second interface 14 for connecting the built-in pipeline 31 to form a circulation loop 5 .

[0054] Furthermore, the circulation loop 5 includes an inner channel 51 and an outer channel 52 , and the outer channel 52 is also disposed between the first interface 13 and the second interface 14 .

[0055] Furthermore, the internal channel 51 is used to connect the built-in pipes 31 to form a circulation loop 5, and the external channel 52 is provided with a water pump 33 and a compressor 34 to accelerate water circulation. The design of the heat dissipation component 3 and the circulation loop 5 adopts a modular structure. This means that the system can be customized and expanded according to different battery pack sizes, heat dissipation requirements and installation environments, and the number and length of the built-in pipes 31 can be increased or decreased, and the power of the water pump 33 and the compressor 34 can be adjusted to meet the needs of different application scenarios.

[0056] Furthermore, the phase change material 2 includes materials such as fatty acids or paraffin, which will melt and absorb heat when heated to a certain temperature to lower the battery temperature; when cooled, they will solidify and release heat to keep the battery temperature stable. The built-in pipe 31 is arranged in a surrounding type inside the phase change material 2, and the water circulation is accelerated by the water pump 33 to absorb the heat of the phase change material 2, thereby achieving the purpose of lowering the battery operating temperature.

[0057] Furthermore, when the temperature sensor 41 detects that the temperature of the battery pack 1 exceeds a set threshold, the control component 4 starts the water pump 33 and the compressor 34 to accelerate the water circulation, and the phase change material 2 and the water in the circulation pipe jointly dissipate the heat of the battery pack 1. When the temperature sensor 41 detects that the temperature of the battery pack 1 continues to rise and the heat absorption capacity of the phase change material 2 is close to saturation, the control component 4 starts additional heat dissipation equipment to enhance the heat dissipation effect and prevent the battery pack from overheating.

[0058] Furthermore, the cooling method includes heat dissipation at normal temperature and heat dissipation at high temperature. Heat dissipation at normal temperature refers to when the vehicle is working and the battery is at normal operating temperature, the phase change material 2 alone is sufficient to cool the battery. Heat dissipation at high temperature refers to when the entire vehicle is overcharged for a long time or the battery continuously outputs current for a long time, the phase change material 2 cannot meet the heat dissipation of the battery pack. When the temperature sensor 41 at the connection port senses that the temperature exceeds the threshold, the water pump 33 will start. The water pump 33 accelerates the flow of water, which can help the phase change material 2 and the battery to dissipate heat together, reducing the capacity attenuation of the battery due to long-term overcharging or excessively long output current and the risk of thermal runaway caused by excessive temperature.

[0059] When the staff needs to use the battery pack 1, the built-in pipe 31 is set inside the phase change material 2 to form a circulating water circuit. When the battery pack 1 generates heat, the phase change material 2 first absorbs the heat and undergoes a phase change, thereby reducing the battery temperature. In order to further improve the heat dissipation efficiency, the heat dissipation component 3 drives the water 32 inside the pipe to circulate in the built-in pipe 31 through the water pump 33 and the compressor 34, and uses the convection heat transfer characteristics of water to quickly take away the heat in the phase change material 2, and release the heat to the external environment through external heat dissipation equipment. The expansion water tank is used to provide and store circulating water to ensure the stable operation of the water circulation loop 5. The temperature sensor 41 monitors the temperature inside the battery pack 1 in real time and transmits the temperature signal to the control component 4. When the temperature reaches or exceeds the predetermined threshold, the control component 4 will immediately start the water pump 33 and the compressor 34 to start the heat dissipation component 3. By adjusting the operating status of the water pump 33 and the compressor 34, the control component 4 can accurately control the speed of water circulation and the heat dissipation efficiency, thereby achieving precise regulation of the battery temperature. The internal channel 51 is arranged between the first interface 13 and the second interface 14 of the battery pack 1 shell 11, and is used to connect the built-in pipe 31 to form a closed water circulation loop 5. The external channel 52 is also arranged between the first interface 13 and the second interface 14, but is located outside the battery pack 1, and is used to install heat dissipation equipment such as the water pump 33 and the compressor 34. This design makes the heat dissipation system more compact, efficient, and easy to maintain and replace.

[0060] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A battery pack heat dissipation method based on phase change material and heat dissipation pipe, comprising a battery pack (1), characterized in that: A housing (11) and a plurality of battery packs (12) arranged inside the housing (11); A phase change material (2) wrapped in each battery group (12) and filled in the battery pack (1); A heat dissipation component (3), which is connected to the battery pack (1) and is used to transfer heat from the battery pack (1) to the outside; A control component (4) used to control the heat dissipation component (3) to dissipate heat when the temperature of the battery pack (1) reaches a predetermined range; The circulation loop (5) includes an inner channel (51) and an outer channel (52).

2. A battery pack heat dissipation method based on phase change material and heat dissipation pipe according to claim 1, characterized in that: The heat dissipation component (3) comprises a built-in pipeline (31), water (32) inside the pipeline, a water pump (33), a compressor (34) and an expansion water tank. The built-in pipeline (31) is arranged inside the phase change material (2) to form a circulating water circuit.

3. A battery pack heat dissipation method based on phase change material and heat dissipation pipe according to claim 2, characterized in that: One end of the built-in pipe (31) is connected to a water pump (33), and the other end of the built-in pipe (31) is connected to a compressor (34), thereby forming a water circulation loop (5). The expansion water tank is connected to the water circulation loop (5) and is used to provide and store circulating water.

4. The method for heat dissipation of a battery pack based on phase change material and heat dissipation pipe according to claim 1, characterized in that: The control component (4) comprises at least one temperature sensor (41) arranged in the battery pack (1); the temperature sensor (41) is arranged in the battery pack (1) and is used to detect the temperature of the battery pack (1); the temperature sensor (41) is connected to the water pump (33) and the compressor (34) and is used to detect the temperature of the battery pack (1) and control the start-up of the water pump (33) and the compressor (34).

5. The method for heat dissipation of a battery pack based on phase change material and heat dissipation pipe according to claim 1, characterized in that: The housing (11) of the battery pack (1) is provided with a first interface (13) and a second interface (14); the internal channel (51) and the external channel (52) are both provided between the first interface (13) and the second interface (14) and are used to connect the built-in pipeline (31) to form a circulation loop (5).

6. The method for heat dissipation of a battery pack based on phase change material and heat dissipation pipe according to claim 1, characterized in that: The circulation loop (5) comprises an inner channel (51) and an outer channel (52), and the outer channel (52) is also arranged between the first interface (13) and the second interface (14).

7. The method for heat dissipation of a battery pack based on phase change material and heat dissipation pipe according to claim 5, characterized in that: The internal channel (51) is used to connect the built-in pipeline (31) to form a circulation loop (5), and the external channel (52) is provided with a water pump (33) and a compressor (34) to accelerate water circulation.

8. The method for heat dissipation of a battery pack based on phase change material and heat dissipation pipe according to claim 1, characterized in that: The phase change material (2) includes materials such as fatty acids or paraffin, which melt when heated to a certain temperature and absorb heat to reduce the battery temperature; when cooled, they solidify and release heat to keep the battery temperature stable. The built-in pipe (31) is arranged in a surrounding shape inside the phase change material (2) and accelerates the circulation of water through a water pump (33), absorbing the heat of the phase change material (2) to achieve the purpose of reducing the operating temperature of the battery.

9. The method for heat dissipation of a battery pack based on phase change material and heat dissipation pipe according to claim 2, characterized in that: When the temperature sensor (41) detects that the temperature of the battery pack (1) exceeds a set threshold, the control component (4) starts the water pump (33) and the compressor (34) to accelerate water circulation, thereby dissipating heat from the battery pack (1) through the phase change material (2) and the water in the circulation pipe.

10. The method for heat dissipation of a battery pack based on phase change material and heat dissipation pipe according to claim 1, characterized in that: The cooling method includes heat dissipation at normal temperature and heat dissipation at high temperature. The heat dissipation at normal temperature refers to when the vehicle is working and the battery is at normal operating temperature, the phase change material (2) alone is sufficient to cool the battery. The heat dissipation at high temperature refers to when the vehicle is overcharged for a long time or the battery continuously outputs current for a long time, the phase change material (2) cannot meet the heat dissipation of the battery pack. When the temperature sensor (41) at the connection port senses that the temperature exceeds a threshold, the water pump (33) will start. The water pump (33) accelerates the flow of water, which can help the phase change material (2) and the battery to dissipate heat together, thereby reducing the capacity attenuation of the battery due to long-term overcharging or long-term output current and the risk of thermal runaway caused by excessive temperature.

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