Battery thermal control system integrating temperature monitoring and efficient cooling

Abstract

The invention discloses a battery thermal control system integrating temperature monitoring and efficient cooling. The battery thermal control system comprises a heat dissipation system, a temperature sensor and an electric heater. The heat dissipation system is prepared by adopting double-network structure hydrogel taking PAM (polyacrylamide) and CaCl2 (calcium chloride) as raw materials, combining with a nano-scale porous design and performing self-crosslinking under the condition of 50 DEG C, and covers the surface of a battery pack or is embedded into a battery gap. The hydrogel realizes efficient heat dissipation through a low-temperature moisture absorption-high-temperature evaporation mechanism, and can quickly absorb heat and evaporate and cool in a high-temperature environment, and experiments show that the temperature of the battery can be reduced by 20 DEG C or above. The temperature sensor monitors the temperature of the battery in real time and dynamically regulates and controls operation of the heat dissipation system and the electric heater according to a signal. When the temperature exceeds a threshold value, hydrogel heat dissipation is started, and in a low-temperature environment, the electric heater is started to maintain the working temperature of the battery. Through an intelligent temperature control strategy, performance degradation and potential safety hazards caused by overheating or supercooling of the battery are solved, meanwhile, the system is compact in structure and low in cost, the heat dissipation module is high in flexibility and can be tightly attached to the surface of the battery, the heat conduction efficiency and the system reliability are remarkably improved, the service life of the battery is prolonged by 30% or above, and the service life of the battery is prolonged. The method is suitable for large-scale application of electric automobiles, energy storage equipment and other scenes.

Description

Technical Field

[0001] The present invention relates to the field of battery thermal management technology, and in particular to a battery thermal control system integrating temperature monitoring and efficient cooling. The system can monitor the battery temperature in real time by integrating temperature monitoring and efficient cooling technology, and achieve efficient cooling through the moisture absorption-evaporation mechanism of hydrogel. At the same time, it is equipped with an electric heater to cope with low temperature environments, ensuring that the battery can work safely and efficiently under various temperature conditions. Background Art

[0002] With the rapid development of electric vehicles, energy storage systems and portable electronic devices, lithium-ion batteries have become the mainstream energy storage carrier due to their high energy density and long cycle life. However, during operation, the battery is prone to local overheating due to factors such as internal resistance heat generation, ambient temperature fluctuations and high-rate charge and discharge. Studies have shown that for every 10°C increase in battery temperature, its cycle life will be shortened by about 50%, and when the temperature exceeds 60°C, thermal runaway may occur, leading to serious safety accidents such as combustion or explosion. Therefore, an efficient thermal management system is crucial to ensure battery performance, life and safety.

[0003] At present, battery thermal management technologies are mainly divided into two categories: passive heat dissipation and active heat dissipation. Passive heat dissipation technology relies on the thermal physical properties of the material itself to achieve heat absorption or diffusion, such as:

[0004] 1. Phase change material (PCM) heat dissipation: The phase change material (such as paraffin and fatty acid) absorbs latent heat during the phase change process to delay temperature rise. However, the thermal conductivity of traditional PCM is generally lower than 0.5W / (m·K), and the heat cannot be quickly discharged, resulting in the failure of heat dissipation after the phase change material absorbs heat and is saturated, and there is a risk of leakage.

[0005] 2. High thermal conductivity filler composite materials: The thermal conductivity is improved by adding materials such as graphene and carbon nanotubes to the polymer matrix (such as silicone and epoxy resin). Although such materials can improve the efficiency of heat diffusion, they lack active temperature control mechanisms and are difficult to cope with sudden high heating conditions.

[0006] 3. Heat pipe technology: It achieves efficient heat transfer through the phase change cycle of the internal working fluid, but its structure is complex, costly, and sensitive to installation angle, which limits its application in flexible or compact battery packs.

[0007] Active cooling technology uses external energy to drive forced cooling. Typical solutions include:

[0008] 1. Forced air cooling: Use fans to drive airflow to remove heat, but the heat dissipation efficiency is significantly affected by the ambient temperature, and uneven temperature distribution is prone to occur in confined spaces.

[0009] 2. Liquid cooling system: Cooling is achieved by circulating coolant (such as water-ethylene glycol) directly in contact with the battery surface or flowing through a cold plate. Although it has strong heat dissipation capacity, it requires the configuration of pumps, pipes and heat exchangers. The system is complex and there is a risk of leakage.

[0010] 3. Semiconductor refrigeration (TEC): It achieves precise temperature control based on the Peltier effect, but when used alone, the cooling efficiency is low and the energy consumption is high, and other heat dissipation methods must be used.

[0011] In addition, existing technologies mostly use a single cooling mode, lacking the coordination of temperature monitoring and dynamic control. For example, some solutions rely only on fixed thresholds to trigger cooling, and cannot adjust strategies according to the real-time thermal load of the battery, resulting in energy waste or delayed temperature control; other solutions integrate temperature sensors, but the monitoring points are sparse, making it difficult to capture local hot spots.

[0012] In summary, the existing battery thermal management technology has the following bottlenecks:

[0013] 1. Passive heat dissipation efficiency is limited: it is difficult to balance the thermal conductivity and latent heat capacity of the material, and the problem of heat accumulation is prominent;

[0014] 2. Active heat dissipation consumes a lot of energy: complex external energy supply systems increase costs and the risk of failure;

[0015] 3. Disconnection between monitoring and control: lack of coordination between high-density temperature sensing and intelligent algorithms, and insufficient response speed and accuracy.

[0016] To address the above issues, there is an urgent need for an intelligent thermal management system that integrates real-time temperature monitoring, efficient passive heat absorption and low-energy active heat dissipation to achieve the multiple goals of precise temperature control, rapid response and energy efficiency optimization. Summary of the invention

[0017] The embodiment of the present application solves the problem of performance degradation and safety hazards caused by excessive battery temperature in the prior art by providing a battery thermal control system that integrates temperature monitoring and efficient cooling, realizes accurate monitoring and efficient cooling of battery temperature, and significantly improves the life and safety of the battery.

[0018] The embodiment of the present application provides a battery thermal control system integrating temperature monitoring and efficient cooling, including:

[0019] 1. Heat dissipation system: Cooling is achieved through the low-temperature water absorption and high-temperature evaporation mechanism of hydrogel.

[0020] 2. Temperature sensor: usually fixed on the surface or inside of the battery casing, used to detect the temperature of the battery pack, judge the actual temperature of the battery based on the signal of the temperature sensor, and send a control signal to adjust the temperature of the battery.

[0021] 3. Electric heater: used to heat the battery and is enabled in low temperature environments to ensure normal operation of the battery.

[0022] Preferably, the hydrogel is prepared by self-crosslinking at 50° C. using raw materials such as PAM (polyacrylamide) and CaCl 2 (calcium chloride) as hygroscopic materials, combined with a double network structure and a nanoscale porous design.

[0023] The present invention also provides a method for preparing the hydrogel, which is specifically:

[0024] Step 1: Dissolve acrylamide AM in deionized water and add CaCl2. After stirring, add a crosslinker to the AM-CaCl2 dispersion. After stirring evenly, continue to add a crosslinking accelerator. After stirring evenly, add a thermal initiator. After stirring evenly, put the solution into an oven to dry to obtain a PAM-CaCl2 base film.

[0025] Step 2: Dissolve acrylamide AM in deionized water and add CaCl2. After stirring, add a crosslinker to the AM-CaCl2 dispersion, stir evenly, continue to add a crosslinking accelerator, stir evenly, add a thermal initiator, stir evenly, and pour the solution on the PAM-CaCl2 base film obtained in step 1. After drying, a PAM / CaCl2 double-layer film is obtained.

[0026] Preferably, the mass ratio of acrylamide to CaCl2 in step one is 1.4 to 3:1; the mass ratio of acrylamide to CaCl2 in step two is 1.6 to 3:1.

[0027] A technical solution provided in the embodiments of the present application has at least the following technical effects or advantages:

[0028] 1. Real-time monitoring and precise temperature control: The temperature sensor collects battery temperature data in real time to ensure timely monitoring. The controller intelligently adjusts the operation of the radiator and electric heater according to the signal of the temperature sensor to achieve precise control of the battery temperature and avoid the battery performance and life being affected by excessively high or low temperature.

[0029] 2. Efficient cooling: Through the moisture absorption-evaporation mechanism of hydrogel, it can quickly cool down in high temperature environment. The hydrogel is made of raw materials such as PAM (polyacrylamide) and CaCl2 (calcium chloride) as hygroscopic materials, combined with a double network structure and nano-scale porous design, and is self-crosslinked at 50°C. It has high hygroscopicity and fast evaporation characteristics, and can absorb heat when the battery temperature rises, reduce the battery temperature through evaporation heat dissipation, and significantly improve the heat dissipation efficiency.

[0030] 3. Low temperature heating: The electric heater heats the battery in a low temperature environment to ensure the normal operation of the battery. The electric heater is installed at the bottom or side of the battery pack and can be started in a low temperature environment to ensure that the battery can still operate efficiently in cold conditions and avoid performance degradation or failure due to low temperature.

[0031] 4. Intelligent control and energy saving: The controller intelligently adjusts the operation of the radiator and electric heater according to the signal of the temperature sensor to achieve precise temperature control. The system can dynamically adjust the heat dissipation and heating strategies according to the actual temperature of the battery, avoid unnecessary energy consumption, and improve the energy efficiency of the system.

[0032] 5. Simple structure and easy maintenance: The battery thermal control system of the present invention has a simple structure and is easy to install and maintain. The design of the hydrogel radiator and electric heater enables the system to operate efficiently in both high and low temperature environments, and has low cost, making it suitable for large-scale applications.

[0033] 6. Extend battery life: Through real-time monitoring and intelligent regulation, the system can effectively avoid battery performance degradation and safety hazards caused by excessively high or low temperatures, significantly extend battery life, and improve battery reliability and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic diagram of the structure of a battery thermal control system according to Embodiment 1 of the present application;

[0035] 1- Cooling system, 2- Temperature sensor, 3- Battery cell or battery pack, 4- Electric heater. DETAILED DESCRIPTION

[0036] The embodiment of the present application solves the problem of performance degradation and safety hazards caused by excessive battery temperature in the prior art by providing a battery thermal control system that integrates temperature monitoring and efficient cooling, realizes accurate monitoring and efficient cooling of battery temperature, and significantly improves the life and safety of the battery.

[0037] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0038] Embodiment 1

[0039] Please refer to Figure 1 This embodiment provides a battery thermal control system integrating temperature monitoring and efficient cooling, which includes a heat dissipation system 1, a temperature sensor 2, a battery cell or a battery pack 3, and an electric heater 4 from top to bottom. The temperature sensor is installed on the outer surface of the battery cell or the battery pack to monitor the battery temperature in real time. The heat dissipation system is composed of a phase change hydrogel and covers the outer surface of the device. The electric heater is installed on the bottom or side of the battery pack to heat the battery in a low temperature environment.

[0040] Embodiment 2

[0041] The battery thermal control system in the first embodiment was tested. Under the condition of 60° C., the system reduced the battery surface temperature to 48° C. within 5 minutes, the heat dissipation efficiency was improved by 40%, and the energy consumption was reduced by 30%.

[0042] In combination with Example 1 and Example 2 of the present application, it can be seen that the battery thermal control system of this embodiment uses raw materials such as PAM (polyacrylamide) and CaCl2 (calcium chloride) as hygroscopic materials, and hydrogels with a double network structure and nano-scale porous design as heat dissipation materials. The double network structure of the hydrogel forms a stable three-dimensional network through the dual effects of chemical cross-linking and physical cross-linking, which can effectively lock moisture and enhance the mechanical strength of the material. The nano-scale porous design provides a large number of microporous channels, which significantly improves the specific surface area and hygroscopic capacity of the hydrogel, so that it can quickly absorb moisture in a low temperature environment, and quickly reduce the battery temperature by evaporation heat dissipation in a high temperature environment. This structural design not only improves the hygroscopic-evaporation efficiency of the hydrogel, but also ensures its stability in multiple cycles, avoiding performance degradation caused by material aging or structural damage. Because the hydrogel itself has the characteristics of high hygroscopicity and rapid evaporation, when the battery temperature rises, the hydrogel can quickly absorb heat and dissipate heat by evaporation, significantly reducing the battery surface temperature. At the same time, the hydrogel's double network structure and nano-scale porous design also enhance its thermal conductivity, allowing heat to be more evenly distributed throughout the material, avoiding local overheating. Experiments have shown that the battery thermal control system using this hydrogel material can reduce the battery temperature by more than 20°C in a high temperature environment, significantly improving the heat dissipation efficiency and safety of the battery. In addition, the flexibility and plasticity of the hydrogel material enable it to fit closely to the battery surface, further improving the heat conduction efficiency and ensuring the stable operation of the battery under various working conditions.

Claims

1. A battery thermal control system integrating temperature monitoring and efficient cooling, the structure includes a heat dissipation system, a temperature sensor, a battery cell or a battery pack, and an electric heater. The heat dissipation system is composed of a hydrogel, which is made of raw materials such as acrylamide (AAM) and MBA and is prepared by self-crosslinking reaction at 50°C, and is doped with a variety of hygroscopic agents such as CaCl2 (calcium chloride).

2. The battery thermal control system according to claim 1, characterized in that: The double network structure of the hydrogel forms a stable three-dimensional network through the dual effects of chemical crosslinking and physical crosslinking, which can effectively lock in moisture and enhance the mechanical strength of the material.

3. The battery thermal control system according to claim 1, characterized in that: The nanoscale porous design of the hydrogel provides a large number of microporous channels, which significantly improves the specific surface area and moisture absorption capacity of the hydrogel, enabling it to quickly absorb water in a low-temperature environment and quickly reduce the battery temperature through evaporative heat dissipation in a high-temperature environment. The hydrogel has excellent viscosity and can be easily attached to the surface of the device. The entire preparation process does not require external energy input, the process is simple, and the raw materials are easy to obtain, which has significant feasibility for industrial production.

4. The battery thermal control system according to claim 1, characterized in that: The preparation method of the hydrogel comprises the following steps: Step 1: dissolve acrylamide AM in deionized water, add CaCl2, stir, add crosslinker to AM-CaCl2 dispersion, stir evenly, then add crosslinking accelerator, stir evenly, add thermal initiator, stir evenly, put the solution into oven and dry, to obtain PAM-CaCl2 basement membrane; Step 2: Dissolve acrylamide AM in deionized water and add CaCl2. After stirring, add a crosslinker to the AM-CaCl2 dispersion, stir evenly, continue to add a crosslinking accelerator, stir evenly, add a thermal initiator, stir evenly, and pour the solution on the PAM-CaCl2 base film obtained in step 1. After drying, a PAM / CaCl2 double-layer film is obtained.

5. The battery thermal control system according to claim 4, characterized in that: The mass ratio of acrylamide to CaCl2 in step one is 1.4 to 3:1; the mass ratio of acrylamide to CaCl2 in step two is 1.6 to 3:

1.

6. The battery thermal control system according to claim 1, characterized in that: The temperature sensor is a high-precision thermocouple or infrared sensor, and the distribution density is 1 to 3 per square centimeter.

7. The battery thermal control system according to claim 1, characterized in that: The controller dynamically adjusts the operation of the radiator and the electric heater through the PID algorithm to achieve precise temperature control.

8. The battery thermal control system according to claim 1, characterized in that: The electric heater is installed at the bottom or side of the battery pack and can be started in a low temperature environment to ensure that the battery can still operate efficiently under cold conditions.

9. The battery thermal control system according to claim 1, characterized in that: The moisture absorption-evaporation mechanism of the hydrogel can reduce the battery temperature by more than 20°C in a high temperature environment, significantly improving the heat dissipation efficiency.

10. The battery thermal control system according to claim 1, characterized in that: The system can dynamically adjust the heat dissipation and heating strategies according to the actual temperature of the battery, thereby avoiding unnecessary energy consumption and improving the energy efficiency of the system.

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