Thermal management control method and system for new-energy vehicle battery fast-charging scenario

Abstract

The present invention relates to the technical field of vehicle thermal management. Disclosed are a thermal management control method and system for a new-energy vehicle battery fast-charging scenario. A battery management module is configured to acquire the current ambient temperature, the current battery temperature and the remaining power level of a battery, and perform processing by means of a fuzzy control algorithm and the center of gravity method, so as to determine a thermal management control activation coefficient; a vehicle control unit is configured to acquire the thermal management control activation coefficient, and on the basis of the thermal management control activation coefficient, determine a battery thermal management operation mode and generate a control instruction; a battery thermal management apparatus is configured to acquire the control instruction, and on the basis of the control instruction, generate a battery air-cooling circuit or a battery refrigerant direct cooling circuit. An optimal battery thermal management operation mode can be determined on the basis of real-time ambient temperature data and real-time battery temperature data, thereby achieving the effect of cooling a battery, achieving the purpose of saving power, and solving the problems of high safety risks and reduced charging efficiency of existing batteries due to an excessively high temperature.

Description

Thermal management control methods and systems for fast charging scenarios of new energy vehicle batteries

[0001] Cross-reference to related applications

[0002] This invention claims priority to Chinese patent application filed on February 24, 2025, with application number 202510204658.2 and entitled "A Thermal Management Control Method and System for Fast Charging Scenarios of New Energy Vehicle Batteries", the entire contents of which are incorporated herein by reference and constitute a part of this invention for all purposes. Technical Field

[0003] This invention relates to the field of automotive thermal management technology, and in particular to a thermal management control method and system for fast charging scenarios of new energy vehicle batteries. Background Technology

[0004] The statements in this section merely refer to the background art related to this invention and do not necessarily constitute prior art.

[0005] Currently, with the rapid development of the new energy vehicle industry, new energy vehicles are gradually gaining favor among consumers due to their high cost-effectiveness and other performance characteristics. Compared with traditional fuel vehicles, the power battery, as the main power source of new energy vehicles, is of paramount importance.

[0006] Thermal management of power batteries directly affects their lifespan, vehicle performance, and safety. Especially during long-distance driving, when high-power fast charging is required, the battery's internal resistance generates significant Joule heat during rapid charging, causing a rapid temperature rise. Excessive battery temperature reduces charging efficiency. Furthermore, the dense packing of cells within the battery pack makes heat dissipation in the central areas more difficult, exacerbating temperature inconsistencies between cells. The accumulation of heat over time in this relatively confined space not only reduces charging and discharging efficiency and power output, but without effective thermal management, the battery temperature may exceed safe operating limits, impacting performance and lifespan, and potentially leading to thermal runaway and safety incidents.

[0007] The battery thermal management system adjusts the battery temperature. Whether it is cooling or heating, it requires the consumption of the battery's own stored electrical energy, which leads to excessively long charging time. Users expect to shorten the fast charging time while ensuring battery safety. How to shorten the charging time and ensure charging safety has become a hot topic for various car companies in the research and development of new energy vehicles. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a thermal management control method and system for fast charging scenarios of new energy vehicle batteries, which improves battery safety and durability, shortens charging time, extends battery life, and thus improves the energy utilization efficiency of electric vehicles.

[0009] In a first aspect, the present invention provides a thermal management and control system for fast charging scenarios of new energy vehicle batteries;

[0010] A thermal management control system for fast charging scenarios of new energy vehicle batteries includes:

[0011] The battery management module is used to collect the current ambient temperature, current battery temperature and remaining battery power, and process them through fuzzy control algorithm and center of gravity method. It uses the membership function value of the battery energy distribution coefficient to determine the thermal management control activation coefficient.

[0012] The vehicle controller is used to obtain the thermal management control activation coefficient, determine the battery thermal management operation mode based on the thermal management control activation coefficient, and generate control commands.

[0013] A battery thermal management device is used to acquire control commands and form a battery air-cooling circuit or a battery refrigerant direct-cooling circuit according to the control commands. The battery air-cooling circuit removes excess heat and absorbs natural air from the environment through a cooler, heat exchanger and evaporator. The battery refrigerant direct-cooling circuit cools down the battery through a cooler, heat exchanger, water-cooled condenser and compressor, and dries the battery using a desiccant bottle.

[0014] In some implementations, the current ambient temperature, current battery temperature, and remaining battery charge are processed using fuzzy control algorithms and the center-of-gravity method. The thermal management control activation coefficient is then determined using the membership function value of the battery energy distribution coefficient, including:

[0015] The current ambient temperature, current battery temperature, remaining battery power, and preset battery comfort temperature are input into the fuzzy controller for processing. The set fuzzy control rules are used to construct the relationship between the input and output, and obtain the membership function of the corresponding battery energy distribution coefficient.

[0016] Calculate the thermal management control activation coefficient based on the membership function values ​​of the battery energy distribution coefficient under all fuzzy control rules.

[0017] In some implementations, determining the battery thermal management operation mode based on the thermal management control activation coefficient specifically means: if the thermal management control activation coefficient is greater than or equal to a preset first threshold and less than a preset second threshold, then the battery thermal management operation mode is air-cooled mode; if the thermal management control activation coefficient is greater than or equal to a preset second threshold and less than a preset third threshold, then the battery thermal management operation mode is refrigerant direct cooling mode.

[0018] In some embodiments, the battery thermal management device includes a cooler, a heat exchanger, an evaporator, a water-cooled condenser, a compressor, a thermostat, and a desiccant.

[0019] The cooler is connected to the heat exchanger, the heat exchanger is connected to the evaporator and the water-cooled condenser respectively, and the evaporator is connected to the cooler; the output end of the water-cooled condenser is connected to a compressor, a temperature controller and a drying bottle in sequence, and the drying bottle is connected to the cooler.

[0020] In some embodiments, a first cooling solenoid valve and a first electronic expansion valve are provided between the cooler and the heat exchanger, and a second electronic expansion valve is provided between the cooler and the evaporator and the drying bottle.

[0021] In some embodiments, a pump is provided between the battery casing and the input end of the cooler, and a second cooling solenoid valve is provided between the output end of the cooler and the battery casing.

[0022] In some implementations, the thermal management control activation coefficient is expressed as:

[0023] In the formula, β i P represents the i-th output quantity. i This represents the membership function value of the output quantity under the i-th fuzzy control rule.

[0024] Secondly, the present invention provides a thermal management control system for fast charging scenarios of new energy vehicle batteries;

[0025] A thermal management control system for fast charging scenarios of new energy vehicle batteries includes:

[0026] The battery management module is used to collect the current ambient temperature, current battery temperature and remaining battery power, and process them through fuzzy control algorithm and center of gravity method. It uses the membership function value of the battery energy distribution coefficient to determine the thermal management control activation coefficient.

[0027] The vehicle controller is used to obtain the thermal management control activation coefficient, determine the battery thermal management operation mode based on the thermal management control activation coefficient, and generate control commands.

[0028] A battery thermal management device is used to acquire control commands and form a battery air-cooling circuit or a battery refrigerant direct-cooling circuit according to the control commands. The battery air-cooling circuit is used for: under the operation of the air-cooled pump, the refrigerant carries away excess heat from the battery through the cooler and exchanges heat with the temperature of the ambient natural wind in the heat exchanger. The battery refrigerant direct-cooling circuit is used for: under the operation of the compressor, the refrigerant exchanges heat with the cooler, heat exchanger, and water-cooled condenser to cool the battery.

[0029] In some implementations, the current ambient temperature, current battery temperature, and remaining battery charge are processed using fuzzy control algorithms and the center-of-gravity method. The thermal management control activation coefficient is then determined using the membership function value of the battery energy distribution coefficient, including:

[0030] The current ambient temperature, current battery temperature, remaining battery power, and preset battery comfort temperature are input into the fuzzy controller for processing. The set fuzzy control rules are used to construct the relationship between the input and output, and obtain the membership function of the corresponding battery energy distribution coefficient.

[0031] Calculate the thermal management control activation coefficient based on the membership function values ​​of the battery energy distribution coefficient under all fuzzy control rules.

[0032] In some implementations, determining the battery thermal management operation mode based on the thermal management control activation coefficient specifically means: if the thermal management control activation coefficient is greater than or equal to a preset first threshold and less than a preset second threshold, then the battery thermal management operation mode is air-cooled mode; if the thermal management control activation coefficient is greater than or equal to a preset second threshold and less than a preset third threshold, then the battery thermal management operation mode is refrigerant direct cooling mode.

[0033] In some embodiments, the battery thermal management device includes a cooler, a heat exchanger, an air-cooled pump, a water-cooled condenser, a compressor, a thermostat, and a check valve;

[0034] The cooler is connected to the heat exchanger, and the heat exchanger is connected to the air-cooled pump and the water-cooled condenser respectively. The air-cooled pump is connected to the cooler. The output end of the water-cooled condenser is connected to a compressor, a temperature controller and a check valve in sequence. The check valve is connected to the cooler.

[0035] In some embodiments, a first cooling solenoid valve and a first electronic expansion valve are provided between the cooler and the heat exchanger, and a second electronic expansion valve is provided between the cooler and the air-cooled pump and the check valve.

[0036] In some embodiments, a pump is provided between the battery casing and the input end of the cooler, and a second cooling solenoid valve is provided between the output end of the cooler and the battery casing.

[0037] In some implementations, the thermal management control activation coefficient is expressed as:

[0038] In the formula, β i P represents the i-th output quantity. i This represents the membership function value of the output quantity under the i-th fuzzy control rule.

[0039] Thirdly, this invention provides a thermal management control method for fast charging scenarios of new energy vehicle batteries;

[0040] A thermal management control method for fast charging scenarios of new energy vehicle batteries, based on the aforementioned thermal management control system for fast charging scenarios of new energy vehicle batteries, includes:

[0041] The battery management module collects the current ambient temperature, current battery temperature, and remaining battery power, and processes them using fuzzy control algorithms and the center of gravity method. It then uses the membership function value of the battery energy distribution coefficient to determine the thermal management control activation coefficient and transmits it to the vehicle controller.

[0042] The vehicle controller receives the thermal management control activation coefficient, determines the battery thermal management operation mode based on the thermal management control activation coefficient, generates control commands, and sends them to the battery thermal management device.

[0043] The battery thermal management device receives control commands and forms either a battery air-cooling circuit or a battery refrigerant direct-cooling circuit according to the control commands.

[0044] In some implementations, the current ambient temperature, current battery temperature, and remaining battery charge are processed using fuzzy control algorithms and the center-of-gravity method. The thermal management control activation coefficient is then determined using the membership function value of the battery energy distribution coefficient, including:

[0045] The current ambient temperature, current battery temperature, remaining battery power, and preset battery comfort temperature are input into the fuzzy controller for processing. The set fuzzy control rules are used to construct the relationship between the input and output, and obtain the membership function of the corresponding battery energy distribution coefficient.

[0046] Calculate the thermal management control activation coefficient based on the membership function values ​​of the battery energy distribution coefficient under all fuzzy control rules.

[0047] In some implementations, determining the battery thermal management operation mode based on the thermal management control activation coefficient specifically means: if the thermal management control activation coefficient is greater than or equal to a preset first threshold and less than a preset second threshold, then the battery thermal management operation mode is air-cooled mode; if the thermal management control activation coefficient is greater than or equal to a preset second threshold and less than a preset third threshold, then the battery thermal management operation mode is refrigerant direct cooling mode.

[0048] Compared with the prior art, the beneficial effects of the present invention are:

[0049] 1. The technical solution provided by this invention can determine the most suitable battery thermal management operation mode based on real-time ambient temperature and battery temperature data during fast charging of new energy batteries, achieve seamless switching between different cooling methods, achieve battery cooling effect and power saving; it can shorten the battery fast charging time and save time costs for car owners during travel.

[0050] 2. The technical solution provided by this invention allows the battery thermal management device to accommodate two thermal management operation modes simply by cooperating with components such as a cooler, evaporator, and water-cooled condenser. Switching between the battery air-cooled circuit and the battery refrigerant direct-cooling circuit can be achieved by switching between the cooling solenoid valve and the electronic expansion valve. It has significant advantages in terms of layout space. Compared with the thermal management system of existing new energy vehicles, the water pipe circuit structure is simplified, highly integrated, and has a significant lightweight effect, obvious cost advantages, and is easy to assemble.

[0051] 3. The technical solution provided by this invention combines a battery air-cooling circuit and a battery refrigerant direct cooling circuit to construct a battery thermal management device. It controls the energy output of the battery to the battery thermal management device according to the current battery status and environmental status. The structure is simple and easy to implement, with low cost, convenient assembly, convenient use, and intuitive and simple operation. It has the characteristics of being scalable.

[0052] 4. The technical solution provided by this invention uses fuzzy control algorithm and center of gravity method to realize the switching and coordinated operation of two cooling methods. It comprehensively considers the battery SOC value, current ambient temperature, battery comfort temperature and current battery temperature to construct fuzzy rules, and realizes accurate solution of battery energy distribution coefficient and thermal management control activation coefficient. Attached Figure Description

[0053] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0054] Figure 1 is a schematic diagram of the execution flow of the thermal management control system for fast charging scenarios of new energy vehicle batteries provided in an embodiment of the present invention;

[0055] Figure 2 is a schematic diagram of the battery thermal management device provided in Embodiment 1 of the present invention;

[0056] Figure 3 is a flowchart illustrating the fuzzy control algorithm provided in an embodiment of the present invention;

[0057] Figure 4 is a flowchart illustrating the thermal management control method for fast charging scenarios of new energy vehicle batteries provided in an embodiment of the present invention.

[0058] Figure 5 is a schematic diagram of the battery thermal management device provided in Embodiment 3 of the present invention;

[0059] In the diagram: 1. Battery casing; 1-1. Battery casing input terminal; 1-2. Battery casing output terminal; 2. Pump; 3. First cooling solenoid valve; 4. First electronic expansion valve; 5. Heat exchanger; 5-1. Heat exchanger input terminal; 5-2a. Heat exchanger first output terminal; 5-2b. Heat exchanger second output terminal; 6. Cooler; 6-a. Battery cooling side; 6-b. Refrigeration side; 6-1a. Battery cooling side input terminal; 6-2a. Battery cooling side output terminal; 6-1b. Refrigeration side input terminal; 6-2b. Refrigeration side output terminal; 7. Second cooling solenoid valve; 8. Second electronic expansion valve; 9. Evaporator; 9'. Air-cooled pump; 10. Water-cooled condenser; 10-1. Water-cooled condenser input terminal; 10-2. Water-cooled condenser output terminal; 11. Temperature sensor; 12. Drying bottle; 12'. Check valve; 13. Thermostat; 14. Compressor; 15. Heat exchange fan; a-1, First pipeline; a-2, Second pipeline; b-1, Third pipeline; b-2, Fourth pipeline; b-3, Fifth pipeline; b-4, Sixth pipeline; b-5, Common pipeline; b-5a, Beginning of common pipeline; b-5b, End of common pipeline; b-6, Seventh pipeline. Detailed Implementation

[0060] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0061] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. Furthermore, it should be understood that the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0062] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0063] Example 1

[0064] The rapid heating of batteries during fast charging can accelerate their aging, reduce their lifespan, and even pose safety risks. Therefore, this invention provides a thermal management and control system for fast charging scenarios of new energy vehicle batteries, which improves battery safety and durability, shortens charging time, extends battery life, and thus improves the energy economy of electric vehicles.

[0065] Next, referring to Figures 1-4, a detailed description will be given of a thermal management control system for fast charging scenarios of new energy vehicle batteries disclosed in this embodiment. This thermal management control system for fast charging scenarios of new energy vehicle batteries includes a battery management module, a vehicle controller, and a battery thermal management device. The battery management module communicates with the vehicle controller via a Controller Area Network (CAN) bus, and the vehicle controller communicates with the battery thermal management device via a CAN bus. The battery management module collects the current ambient temperature, current battery temperature, and remaining battery charge, and processes them using fuzzy control algorithms and the center of gravity method to determine the thermal management control activation coefficient. The vehicle controller obtains the thermal management control activation coefficient, determines the battery thermal management operation mode based on the coefficient, and generates control commands. The battery thermal management device obtains the control commands and forms either a battery air-cooling circuit or a battery refrigerant direct-cooling circuit based on the commands. The battery air-cooling circuit removes excess heat and absorbs natural air from the environment via a cooler 6, a heat exchanger 5, and an evaporator 9. The battery refrigerant direct-cooling circuit cools the battery via a cooler 6, a heat exchanger 5, a water-cooled condenser 10, and a compressor 14, and dries the battery using a desiccant bottle 12.

[0066] Furthermore, the execution flow of the thermal management control system for fast charging scenarios of new energy vehicle batteries is as follows:

[0067] S1. The battery management module collects the current ambient temperature, current battery temperature, and remaining battery power, and processes them using fuzzy control algorithm and centroid method. It then uses the membership function value of the battery energy distribution coefficient to determine the thermal management control activation coefficient.

[0068] Here, the battery management module refers to the battery management system (BMS) of new energy vehicle batteries.

[0069] As one implementation method, the current ambient temperature, current battery temperature, and remaining battery power are processed using fuzzy control algorithms and the center of gravity method to determine the thermal management control activation coefficient, including:

[0070] Step 1: Input the current ambient temperature, current battery temperature, remaining battery power, and preset battery comfort temperature into the fuzzy controller for processing. Use the set fuzzy control rules to build the relationship between the input and output, and obtain the membership function of the corresponding battery energy distribution coefficient.

[0071] Furthermore, firstly, the current ambient temperature, current battery temperature, remaining battery power, and preset battery comfort temperature are fuzzed.

[0072] Specifically, the remaining battery charge (State of Charge, SOC) value S is fuzzified. The fuzzification of SOC value S is as follows: when 0 ≤ S < 45%, it is a small positive value; when 45% ≤ S < 70%, it is a medium positive value; and when 70% ≤ S ≤ 100%, it is a large positive value. Let ps be the small positive value, pm the medium positive value, and pb the large positive value. Then the universe of discourse for the input variable S is [0 1], and the fuzzy subset is S = {ps, pm, pb}. Let the battery comfort temperature be T. The difference Δt between the current ambient temperature and the battery comfort temperature is fuzzified. The fuzzification of the difference Δt is as follows: Δt = |h t -T|, is a positive minimum when 0≤Δt<10, a positive middle when 10≤Δt<20, and a positive maximum when 20≤Δt≤35. Let ps-positive minimum, pm-positive middle, pb-positive maximum, and the universe of discourse for the input variable Δt be [0 35]. After normalizing the universe of discourse for Δt, the universe of discourse for the input variable Δt is [0 1]. The fuzzy subset Δt={ps,pm,pb}; for the current battery temperature d t The fuzzification process is performed based on the range of battery temperature changes during charging. The current battery temperature d... t The fuzzification process is specifically as follows: when 0 ≤ d t When <10, it is a positive minimum value; when 10≤d, it is a positive minimum value. t The median value is between 25 and 25, and between 25 and d. t When ≤40 is considered a positive value, let ns be the smallest, nm the middle, and nb the largest. Then d t The universe of discourse for the input variable is [0 40], and similarly for d t If the universe of discourse is normalized, then d t The universe of discourse is [0 1], and the fuzzy subset is S = {ns, nm, nb}. The degree of membership function of the output variable battery energy distribution coefficient K is expressed in trigonometric form and is determined by three key parameters. The mathematical expression is (a, b, c). The universe of discourse is [0 1], and the fuzzy subset is K = {ps, pm, pb}.

[0073] Based on the above analysis, fuzzy control rules were formulated using the logical language form of "If…and…then…". For a multi-input, single-output fuzzy control system, 27 fuzzy control rules were established as shown in Table 1-1, linking input and output factors. The rule expression is: If(v′ is v′) i and h is h i and f is f i Then freg = K.

[0074] Table 1-1 Fuzzy Control Rules

[0075] Step 2: Calculate the thermal management control activation coefficient according to the implementation rules of the center of gravity method and transmit it to the vehicle controller. The thermal management control activation coefficient P is expressed as:

[0076] In the formula, P i The output β under each fuzzy control rule i Membership function value.

[0077] Fuzzy inference yields a fuzzy value, but the actual output required is an accurate value. Therefore, the fuzzy value needs to be clarified. The centroid method is actually a kind of analogy technique that can represent the intersection value of the centroid of the region formed by the membership function curve and the basic variable axis as an accurate value.

[0078] Step 2: The vehicle controller receives the thermal management control activation coefficient, determines the battery thermal management operation mode based on the thermal management control activation coefficient, and generates corresponding control commands to send to the battery thermal management device; the battery thermal management device performs cooling according to the control commands.

[0079] Specifically, if the thermal management control activation coefficient is greater than or equal to 0 and less than the preset first threshold, the battery thermal management device will not be activated for battery cooling; if the thermal management control activation coefficient is greater than or equal to the preset first threshold and less than the preset second threshold, the battery thermal management operation mode is air-cooled mode; if the thermal management control activation coefficient is greater than or equal to the preset second threshold and less than the preset third threshold, the battery thermal management operation mode is refrigerant direct cooling mode.

[0080] Furthermore, the battery thermal management device includes a cooler 6, a heat exchanger 5, an evaporator 9, and a water-cooled condenser 10, a compressor 14, a thermostat 13, and a dryer bottle 12 connected in sequence by pipes. The battery is installed in a battery casing 1, which is fitted over the battery and has a certain distance between it and the battery's outer surface. The output end of the battery casing 1 is connected to the input end of the cooler 6 through a pipe, and a pump 2 is installed on the pipe. The output end of the cooler 6 is connected to the input end of the battery casing 1, and a second cooling solenoid valve 7 is installed on the pipe. The input end of the cooler 6 is connected to the input end of the heat exchanger 5 through a pipe. A first cooling solenoid valve 3 and a first electronic expansion valve 4 are installed in sequence between the cooler 6 and the heat exchanger 5. The output end of the heat exchanger 5 is connected to the evaporator 9 and the water-cooled condenser 10 through pipes. The output end of the evaporator 9 is connected to the input end of the cooler 6, and the dryer bottle 12 is connected to the input end of the cooler 6. A second electronic expansion valve 8 is installed on the common pipe between the cooler 6, the evaporator 9, and the dryer bottle 12.

[0081] For example, when 0 ≤ p < 0.45, the battery thermal management device is not activated to cool the battery.

[0082] When 0.45≤p<0.625, the battery thermal management device activates air cooling to cool the battery; pump 2, cooler 6, second cooling solenoid valve 7, first cooling solenoid valve 3, first electronic expansion valve 4, heat exchanger 5, and evaporator 9 are started, while the remaining components are in the off state; starting from the battery casing 1, excess heat is carried away through the first cooling solenoid valve 3 and heat exchanger 5, and natural air from the environment is absorbed, passing through evaporator 9 to heat exchanger 5 to battery casing 1 to form a battery air cooling circuit. This mode has the advantages of simple operation and low power consumption.

[0083] When 0.625≤p≤1, the battery thermal management device activates the refrigerant direct cooling mode to cool the battery. This involves starting pump 2, cooler 6, second cooling solenoid valve 7, first cooling solenoid valve 3, first electronic expansion valve 4, heat exchanger 5, water-cooled condenser 10, compressor 14, thermostat 13, and dryer bottle 12, while the remaining components remain off. Excess heat is removed from the battery casing 1 via cooler 6 and heat exchanger 5, and then cooled by water-cooled condenser 10 and compressor 14. Temperature sensor 11 collects and controls the required temperature, and the low-temperature gas is dried via dryer bottle 12 to prevent excessive humidity from damaging the battery. The refrigerant direct cooling circuit from cooler 6 to battery casing 1 is formed, providing the advantage of rapid cooling.

[0084] Example 2

[0085] Referring to Figure 4, based on the thermal management control system for fast charging scenarios of new energy vehicle batteries described in Embodiment 1, this embodiment discloses a thermal management control method for fast charging scenarios of new energy vehicle batteries, including:

[0086] The battery management module collects the current ambient temperature, current battery temperature, and remaining battery power, and processes them using fuzzy control algorithms and the center of gravity method. It then uses the membership function value of the battery energy distribution coefficient to determine the thermal management control activation coefficient and transmits it to the vehicle controller.

[0087] The vehicle controller receives the thermal management control activation coefficient, determines the battery thermal management operation mode based on the thermal management control activation coefficient, generates control commands, and sends them to the battery thermal management device.

[0088] The battery thermal management device receives control commands and forms either a battery air-cooling circuit or a battery refrigerant direct-cooling circuit according to the control commands.

[0089] Example 3

[0090] Referring to Figures 1 and 3-5, a detailed description of a thermal management control system for fast charging scenarios of new energy vehicle batteries disclosed in this embodiment will be provided. This thermal management control system for fast charging scenarios of new energy vehicle batteries includes a battery management module, a vehicle controller, and a battery thermal management device. The battery management module is connected via a controller area network (Controller Area Network). The battery management module communicates with the vehicle controller via a CAN bus, and the vehicle controller communicates with the battery thermal management device via the CAN bus. The battery management module collects the current ambient temperature, current battery temperature, and remaining battery charge, and processes them using fuzzy control algorithms and the center of gravity method to determine the thermal management control activation coefficient. The vehicle controller obtains the thermal management control activation coefficient, determines the battery thermal management operation mode based on the coefficient, and generates control commands. The battery thermal management device obtains the control commands and forms either a battery air-cooling circuit or a battery refrigerant direct-cooling circuit based on the commands. In the battery air-cooling circuit, the refrigerant, under the action of the air-cooled pump 9', carries away excess heat from the battery via the cooler 6 and exchanges heat with the ambient air temperature in the heat exchanger 5. In the battery refrigerant direct-cooling circuit, the refrigerant, under the action of the compressor 14, exchanges heat with the cooler 6, heat exchanger 5, and water-cooled condenser 10 to cool the battery. The check valve 12' is used to prevent liquid return and generate liquid slugging on the compressor 14.

[0091] Furthermore, the execution flow of the thermal management control system for fast charging scenarios of new energy vehicle batteries is as follows:

[0092] S1. The battery management module collects the current ambient temperature, current battery temperature, and remaining battery power, and processes them using fuzzy control algorithm and centroid method. It then uses the membership function value of the battery energy distribution coefficient to determine the thermal management control activation coefficient.

[0093] Here, the battery management module refers to the battery management system (BMS) of new energy vehicle batteries.

[0094] As one implementation method, the current ambient temperature, current battery temperature, and remaining battery power are processed using fuzzy control algorithms and the center of gravity method to determine the thermal management control activation coefficient, including:

[0095] Step 1: Input the current ambient temperature, current battery temperature, remaining battery power, and preset battery comfort temperature into the fuzzy controller for processing. Use the set fuzzy control rules to build the relationship between the input and output, and obtain the membership function of the corresponding battery energy distribution coefficient.

[0096] Step 1.1: Add a temperature energy consumption sub-controller and a power safety sub-controller to the fuzzy controller to build a two-layer fuzzy inference architecture.

[0097] In this embodiment, the two-layer fuzzy inference architecture includes a first-layer local decision layer and a second-layer global coordination layer. The first layer contains two independently operating sub-controllers: a temperature and energy consumption sub-controller and a power safety sub-controller. They simultaneously receive sensor data and calculate and output the local energy allocation coefficient K of the temperature and energy consumption sub-controller. T and the local energy distribution coefficient K of the safety sub-controller S The two local energy distribution coefficients are then sent together to the second layer for fusion.

[0098] Step 1.2: Perform fuzzing processing on the current ambient temperature, current battery temperature, remaining battery power, and preset battery comfort temperature.

[0099] Specifically, the remaining battery charge (State of Charge, SOC) value S is fuzzified. The fuzzification of SOC value S is as follows: when 0 ≤ S < 45%, it is a small positive value; when 45% ≤ S < 70%, it is a medium positive value; and when 70% ≤ S ≤ 100%, it is a large positive value. Let ps be the small positive value, pm the medium positive value, and pb the large positive value. Then the universe of discourse for the input variable S is [0 1], and the fuzzy subset is S = {ps, pm, pb}. Let the battery comfort temperature be T. The difference Δt between the current ambient temperature and the battery comfort temperature is fuzzified. The fuzzification of the difference Δt is as follows: Δt = |h t -T|, is a positive minimum when 0≤Δt<10, a positive middle when 10≤Δt<20, and a positive maximum when 20≤Δt≤35. Let ps-positive minimum, pm-positive middle, pb-positive maximum, and the universe of discourse for the input variable Δt be [0 35]. After normalizing the universe of discourse for Δt, the universe of discourse for the input variable Δt is [0 1]. The fuzzy subset Δt={ps,pm,pb}; for the current battery temperature d t The fuzzification process is performed based on the range of battery temperature changes during charging. The current battery temperature d... t The fuzzification process is specifically as follows: when 0 ≤ d t When <10, it is a positive minimum value; when 10≤d, it is a positive minimum value. t The median value is between 25 and 25, and between 25 and d. t When ≤40 is considered a positive value, let ns be the smallest, nm the middle, and nb the largest. Then d t The universe of discourse for the input variable is [0 40], and similarly for d t If the universe of discourse is normalized, then d t The universe of discourse is [0 1], and the fuzzy subset is d. t = {ns, nm, nb}.

[0100] Step 1.3: Utilize the set fuzzy control rules to construct the relationship between input and output, and obtain the membership function of the corresponding battery energy distribution coefficient.

[0101] Output variable: Battery energy distribution coefficient K f The degree of membership function is represented in trigonometric form and is determined by three key parameters. It is mathematically expressed as (a, b, c), with a domain of [0 1] and a fuzzy subset partition of K = {ps, pm, pb}.

[0102] Based on the above analysis, fuzzy control rules were formulated using the logical language form of "If…and…then…". For a multi-input, single-output fuzzy control system, 27 fuzzy control rules were established as shown in Table 1-1, linking input and output factors. The rule expression is: If(v′ is v′) i and h is h i and f is f i Then freg = K.

[0103] Table 1-1 Fuzzy Control Rules

[0104] In one specific implementation, to achieve more flexible and accurate fuzzy control, this embodiment further introduces an adaptive membership function adjustment mechanism. Based on the traditional triangular membership function, an adaptive adjustment factor λ(t) is added, causing the shape of the membership function to dynamically change with the degree of battery aging: μ′(x)=μ(x)·[1+λ(t)·α·SOH];

[0105] Where μ(x) is the triangular membership function, μ′(x) is the adjusted membership function, SOH is the battery state of health, and α is the aging sensitivity coefficient (taken as 0.1-0.3). When the battery ages (SOH<80%), the membership boundary of the temperature comfort range is automatically widened, the thermal management trigger threshold is reduced, and the battery performance degradation is delayed.

[0106] Step 2: Calculate the thermal management control activation coefficient according to the implementation rules of the center of gravity method and transmit it to the vehicle controller. The thermal management control activation coefficient P is expressed as:

[0107] In the formula, P i Let β be the output quantity under the i-th fuzzy control rule. i Membership function value.

[0108] Fuzzy inference yields a fuzzy value, but the actual output required is an accurate value. Therefore, the fuzzy value needs to be clarified. The centroid method is actually a kind of analogy technique that can represent the intersection value of the centroid of the region formed by the membership function curve and the basic variable axis as an accurate value.

[0109] This embodiment employs a two-layer fuzzy inference architecture, which uses the centroid method to perform fuzzy inference on the fuzzified remaining battery power, the difference between the current ambient temperature and the battery's comfortable temperature, and the current battery temperature.

[0110] Based on the two-layer fuzzy inference architecture designed in this embodiment, the battery energy allocation coefficient K f Including the local energy distribution coefficient K of the temperature energy consumption sub-controller T and the local energy distribution coefficient K of the safety sub-controller S Two local energy distribution coefficients.

[0111] More specifically, K T It reacts quickly to temperature changes, automatically increasing to its maximum during emergency overheating, while minimizing energy consumption under normal operating conditions. The first-level local decision-making layer calculates K. T The specific principle is as follows:

[0112] Input ambient temperature, current battery temperature, and preset comfort temperature. First, calculate the difference between the ambient temperature and the comfort temperature, and simultaneously calculate the current battery temperature's position within the safe charging range. Then, convert both values ​​into fuzzy linguistic values. Next, obtain the corresponding fuzzy subsets according to the set fuzzy control rules. Finally, fuse the corresponding fuzzy outputs from the temperature and energy consumption sub-controller and defuzzify them using the centroid method to obtain K. T .

[0113] K T The larger the value, the more energy is needed to control the temperature.

[0114] More specifically, K S The decision-making is relatively conservative, actively limiting thermal management energy consumption when the battery is low and automatically increasing the protection level when the battery is aging.

[0115] The first-level local decision-making layer calculates K. S The specific principle is as follows:

[0116] Input the remaining battery power and obtain the power demand and battery health status according to existing methods. In this embodiment, since the pedal opening is proportional to the power, the pedal opening can be directly used as a substitute indicator for the power demand.

[0117] Battery health is the ratio of the battery's current maximum usable capacity to its original factory capacity. This can be determined using existing offline calibration methods or online estimation methods, which will not be elaborated upon here. The remaining battery capacity is converted into a fuzzy value. Then, according to the set fuzzy control rules, the corresponding fuzzy subset is obtained. The fuzziness is then resolved using the centroid method to obtain K. S The fuzzy subset is then corrected based on power demand and battery health.

[0118] After each of the two sub-controllers has completed its calculations, it outputs K. T and K S The parameters are labeled with auxiliary information such as thermal urgency, power criticality, temperature fluctuations, and power margin. This auxiliary information helps the second layer make better fusion decisions.

[0119] The second layer introduces a coordination factor ω∈[0,1], and calculates the final thermal management control activation coefficient using a weighted fusion algorithm: K f =ω·K T +(1-ω)·K S +Γ·ΔT gradient ;

[0120] Among them, K f The battery energy distribution coefficient, which serves as the final thermal management control activation coefficient, is ω, a weighting coefficient, Γ, a temperature gradient penalty coefficient, and ΔT. gradient The maximum temperature difference between battery modules is 5°C. When the temperature difference exceeds 5°C, the forced equalization mode is activated.

[0121] It should be noted that K is obtained by correcting the fuzzy subset based on power demand and battery health. S The specific steps include:

[0122] First, power demand is adjusted based on pedal opening. The power demand is determined by the pedal opening. When the demand is high, K... S Increased, limiting thermal management power consumption to prioritize power supply; demand hours K S The adjustment allows for greater energy utilization in thermal management. The correction employs piecewise linear interpolation, mapping the pedal opening to directly superimposed compensation values.

[0123] Then, battery health calibration is performed based on power demand calibration. For example, no adjustment or slight downward adjustment is made when the battery health is above 90%; a small upward adjustment is made between 70% and 90%; and a larger upward adjustment is made below 70%. The battery health is directly adjusted by looking up the corresponding compensation value in a preset table and then added to the current K. S .

[0124] Finally, a security check is performed based on the boundary protection strategy. K is then corrected through two rounds of adjustments. SCheck if the settings exceed a reasonable range. When the battery is extremely low, force it to stay above the safety threshold; when the temperature is extremely high, force it to stay above the over-control threshold, ensuring safety takes priority in extreme situations.

[0125] Step 3: The vehicle controller receives the thermal management control activation coefficient, determines the battery thermal management operation mode based on the thermal management control activation coefficient, and generates corresponding control commands to send to the battery thermal management device; the battery thermal management device performs cooling according to the control commands.

[0126] Specifically, if the thermal management control activation coefficient is greater than or equal to 0 and less than the preset first threshold, the battery thermal management device will not be activated for battery cooling; if the thermal management control activation coefficient is greater than or equal to the preset first threshold and less than the preset second threshold, the battery thermal management operation mode is air-cooled mode; if the thermal management control activation coefficient is greater than or equal to the preset second threshold and less than the preset third threshold, the battery thermal management operation mode is refrigerant direct cooling mode.

[0127] Furthermore, the battery thermal management device includes a battery cooling circuit and a switchable mode cooling circuit:

[0128] The battery cooling circuit includes a battery housing 1, which is fitted onto the outside of the battery and has a certain gap with the outer surface of the battery. The output terminal 1-2 on the battery housing 1 is connected to the input terminal 6-1a of the battery cooling side 6-a of the cooler 6 through a first pipe a-1. A pump 2 is installed on the first pipe a-1. The output terminal 6-2a of the battery cooling side 6-a of the cooler 6 is connected to the input terminal 1-1 on the battery housing 1 through a second pipe a-2. A second cooling solenoid valve 7 and a temperature sensor 11 are installed on the second pipe a-2. The battery cooling circuit is filled with a recirculating battery cooling medium.

[0129] Switchable mode cooling circuit, including:

[0130] The output terminal 6-2b of the cooling side 6-b of the cooler 6 is connected to the input terminal 5-1 of the heat exchanger 5 via a third pipe b-1. A first cooling solenoid valve 3 and a first electronic expansion valve 4 are installed sequentially between the output terminal 6-2b of the cooling side 6-b of the cooler 6 and the input terminal 5-1 of the heat exchanger 5. The first output terminal 5-2a of the heat exchanger 5 is connected to the air-cooled pump 9' via a fourth pipe b-2. The second output terminal 5-2b of the heat exchanger 5 is connected to the input terminal 10-1 of the water-cooled condenser 10 via a fifth pipe b-3. The output of the air-cooled pump 9' is connected to the common pipe b-5 via a sixth pipe b-4. The end b-5b of the common pipe b-5 is connected to the input end 6-2a of the cooling side 6-b of the cooler 6; the output end 10-2 of the water-cooled condenser 10 is connected to the beginning end b-5a of the common pipe b-5 through the seventh pipe b-6. A check valve 12', a thermostat 13 and a compressor 14 are installed sequentially between the beginning end b-5a of the common pipe b-5 and the output end 10-2 of the water-cooled condenser 10; a second electronic expansion valve 8 is also installed on the part of the common pipe b-5 between the cooler 6 and the sixth pipe b-4; the switchable mode refrigeration circuit is filled with a recirculating refrigerant.

[0131] The switchable cooling circuit can be controlled by the battery thermal management device to activate air cooling mode, refrigerant direct cooling mode, or switch between air cooling mode and refrigerant direct cooling mode to cool and reduce the temperature of the battery.

[0132] For example, when 0 ≤ p < 0.45, the battery thermal management device is not activated to cool the battery.

[0133] When 0.45 ≤ p < 0.625, the battery thermal management device activates the air-cooling mode to cool the battery. Specifically, pump 2, cooler 6, second cooling solenoid valve 7, first cooling solenoid valve 3, first electronic expansion valve 4, heat exchanger 5, air-cooled pump 9', and second electronic expansion valve 8 are started, while the remaining components are closed. The battery cooling medium begins to circulate, carrying excess heat from the battery casing 1 to the battery cooling side 6-a of the cooler 6. Simultaneously, the refrigerant circulates from the cooling side 6-b of the cooler 6. The first cooling solenoid valve 3 carries excess heat from the battery, exchanged from the battery cooling side 6-a of the cooler 6, to the heat exchanger 5. The heat exchange fan 15 on the heat exchanger 5 starts, blowing natural air into the heat exchanger 5 to remove the excess heat from the refrigerant. The air-cooled refrigerant, after being cooled, returns to the cooling side 6-b of the cooler 6 through the work of the air-cooled pump 9', continuing to remove excess heat absorbed from the battery casing 1 by the battery cooling medium in the battery cooling side 6-a, thus achieving air-cooling of the battery. At this time, the check valve 12' closes to prevent refrigerant backflow, which could cause liquid slugging on the temperature controller 13 and compressor 14. This mode has the advantages of simple operation and low power consumption.

[0134] When 0.625≤p≤1, the battery thermal management device activates the direct refrigerant cooling mode to cool the battery. Specifically, pump 2, cooler 6, second cooling solenoid valve 7, first cooling solenoid valve 3, first electronic expansion valve 4, heat exchanger 5, water-cooled condenser 10, compressor 14, thermostat 13, and second electronic expansion valve 8 are started. Check valve 12' is opened to allow refrigerant flow, while the other components are closed. The battery cooling medium begins to circulate, carrying excess heat from the battery casing 1 to the battery cooling side 6-a of cooler 6. Simultaneously, the refrigerant circulates under the power of compressor 14, starting from the cooling side 6-b of cooler 6, passing sequentially through first cooling solenoid valve 3, heat exchanger 5, and water-cooled condenser 10. After water cooling in water-cooled condenser 10, it flows back to the cooling side 6-b of cooler 6 to absorb excess heat from the battery casing 1 absorbed by the battery cooling medium in battery cooling side 6-a, thereby achieving the effect of cooling the battery. The above circuit forms a direct cooling circuit for the battery refrigerant, which has the advantage of rapid cooling effect.

[0135] Temperature sensor 11 collects the temperature in the second pipeline a-2 and feeds it back to the BMS to control the required temperature of the battery cooling medium in the second pipeline a-2; check valve 12' is used to prevent the refrigerant in the common pipeline b-5 from flowing back into the thermostat 13 and compressor 14 in the air-cooled mode, thereby preventing the refrigerant from flowing back into the thermostat 13 and compressor 14, causing liquid slugging, damaging the thermostat 13 and compressor 14, and affecting the service life of the thermostat 13 and compressor 14.

[0136] It should be noted that the above steps correspond to the execution steps of the thermal management control system for fast charging scenarios of new energy vehicle batteries described in Embodiment 1, and the specific details will not be repeated in this embodiment.

[0137] The descriptions of each embodiment in the above embodiments have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0138] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A thermal management control system for fast charging scenarios of new energy vehicle batteries, characterized in that, include: The battery management module is used to collect the current ambient temperature, current battery temperature, and remaining battery power, and process them using fuzzy control algorithms and the center of gravity method. It uses the membership function value of the battery energy distribution coefficient to determine the thermal management control activation coefficient. The vehicle controller is used to obtain the thermal management control activation coefficient, determine the battery thermal management operation mode based on the thermal management control activation coefficient, and generate control commands. A battery thermal management device is used to acquire control commands and form a battery air-cooling circuit or a battery refrigerant direct-cooling circuit according to the control commands; wherein, the battery air-cooling circuit is used to remove excess heat and absorb natural wind from the environment through a cooler, heat exchanger and evaporator, and the battery refrigerant direct-cooling circuit is used to cool down through a cooler, heat exchanger, water-cooled condenser and compressor, and to dry using a drying bottle. The current ambient temperature, current battery temperature, and remaining battery charge are processed using fuzzy control algorithms and the center-of-gravity method. The thermal management control activation coefficient is determined using the membership function value of the battery energy distribution coefficient, including: The current ambient temperature, current battery temperature, remaining battery power, and preset battery comfort temperature are input into the fuzzy controller for processing. The set fuzzy control rules are used to construct the relationship between the input and output, and obtain the membership function of the corresponding battery energy distribution coefficient. Calculate the thermal management control activation coefficient based on the membership function values ​​of the battery energy distribution coefficient under all fuzzy control rules; The determination of the battery thermal management operation mode based on the thermal management control activation coefficient is as follows: if the thermal management control activation coefficient is greater than or equal to a preset first threshold and less than a preset second threshold, the battery thermal management operation mode is air-cooled mode; if the thermal management control activation coefficient is greater than or equal to a preset second threshold and less than a preset third threshold, the battery thermal management operation mode is refrigerant direct cooling mode.

2. The thermal management control system for fast charging scenarios of new energy vehicle batteries as described in claim 1, characterized in that, The battery thermal management device includes a cooler, a heat exchanger, an evaporator, a water-cooled condenser, a compressor, a temperature controller, and a desiccant. The cooler is connected to the heat exchanger, the heat exchanger is connected to the evaporator and the water-cooled condenser respectively, and the evaporator is connected to the cooler; the output end of the water-cooled condenser is connected to a compressor, a temperature controller and a drying bottle in sequence, and the drying bottle is connected to the cooler.

3. The thermal management control system for fast charging scenarios of new energy vehicle batteries as described in claim 2, characterized in that, A first cooling solenoid valve and a first electronic expansion valve are provided between the cooler and the heat exchanger, and a second electronic expansion valve is provided between the cooler and the evaporator and the drying bottle.

4. The thermal management control system for fast charging scenarios of new energy vehicle batteries as described in claim 2, characterized in that, A pump is installed between the battery casing and the input end of the cooler, and a second cooling solenoid valve is installed between the output end of the cooler and the battery casing. 5.The thermal management control system for new energy vehicle battery fast charging scenario according to claim 1, wherein, The thermal management control activation coefficient is expressed as: In the formula, β i P represents the output quantity. i Let β represent the output quantity under the i-th fuzzy control rule. i The membership function value.

6. A thermal management control method for fast charging scenarios of new energy vehicle batteries, based on the thermal management control system for fast charging scenarios of new energy vehicle batteries as described in any one of claims 1-5, characterized in that, include: The battery management module collects the current ambient temperature, current battery temperature, and remaining battery power, and processes them using fuzzy control algorithms and the center of gravity method to determine the thermal management control activation coefficient and transmit it to the vehicle controller. The vehicle controller receives the thermal management control activation coefficient, determines the battery thermal management operation mode based on the thermal management control activation coefficient, generates control commands, and sends them to the battery thermal management device. The battery thermal management device receives control commands and forms either a battery air-cooling circuit or a battery refrigerant direct-cooling circuit according to the control commands.

7. The thermal management control method for fast charging scenarios of new energy vehicle batteries as described in claim 6, characterized in that, By processing the current ambient temperature, current battery temperature, and remaining battery charge using fuzzy control algorithms and the center-of-gravity method, the thermal management control activation coefficient is determined, including: The current ambient temperature, current battery temperature, remaining battery power, and preset battery comfort temperature are input into the fuzzy controller for processing. The set fuzzy control rules are used to construct the relationship between the input and output, and obtain the membership function of the corresponding battery energy distribution coefficient. Calculate the thermal management control activation coefficient based on the membership function values ​​of the battery energy distribution coefficient under all fuzzy control rules.

8. The thermal management control method for fast charging scenarios of new energy vehicle batteries as described in claim 6, characterized in that, The determination of the battery thermal management operation mode based on the thermal management control activation coefficient is as follows: if the thermal management control activation coefficient is greater than or equal to a preset first threshold and less than a preset second threshold, the battery thermal management operation mode is air-cooled mode; if the thermal management control activation coefficient is greater than or equal to a preset second threshold and less than a preset third threshold, the battery thermal management operation mode is refrigerant direct cooling mode.

9. A thermal management control system for fast charging scenarios of new energy vehicle batteries, characterized in that, include: The battery management module is used to collect the current ambient temperature, current battery temperature, and remaining battery power, and process them using fuzzy control algorithms and the center of gravity method. It uses the membership function value of the battery energy distribution coefficient to determine the thermal management control activation coefficient. The vehicle controller is used to obtain the thermal management control activation coefficient, determine the battery thermal management operation mode based on the thermal management control activation coefficient, and generate control commands. A battery thermal management device is used to acquire control commands and form a battery air-cooling circuit or a battery refrigerant direct cooling circuit according to the control commands. The battery air-cooling circuit is used for: With the work done by the air-cooled pump, the refrigerant carries away the excess heat from the battery through the cooler and absorbs the temperature of the natural wind in the environment for heat exchange in the heat exchanger. The battery refrigerant direct cooling circuit is used for: Under the action of the compressor, the refrigerant exchanges heat with the cooler, heat exchanger and water-cooled condenser to cool the battery; The current ambient temperature, current battery temperature, and remaining battery charge are processed using fuzzy control algorithms and the center-of-gravity method. The thermal management control activation coefficient is determined using the membership function value of the battery energy distribution coefficient, including: The current ambient temperature, current battery temperature, remaining battery power, and preset battery comfort temperature are input into the fuzzy controller for processing. The set fuzzy control rules are used to construct the relationship between the input and output, and obtain the membership function of the corresponding battery energy distribution coefficient. Calculate the thermal management control activation coefficient based on the membership function values ​​of the battery energy distribution coefficient under all fuzzy control rules; The determination of the battery thermal management operation mode based on the thermal management control activation coefficient is as follows: if the thermal management control activation coefficient is greater than or equal to a preset first threshold and less than a preset second threshold, the battery thermal management operation mode is air-cooled mode; if the thermal management control activation coefficient is greater than or equal to a preset second threshold and less than a preset third threshold, the battery thermal management operation mode is refrigerant direct cooling mode.

10. The thermal management control system for fast charging scenarios of new energy vehicle batteries as described in claim 9, characterized in that, The battery thermal management device includes: Coolers, heat exchangers, air-cooled pumps, water-cooled condensers, compressors, thermostats, and check valves; The cooler is connected to the heat exchanger, the heat exchanger is connected to the air-cooled pump and the water-cooled condenser respectively, and the air-cooled pump is connected to the cooler; the output end of the water-cooled condenser is connected to a compressor, a temperature controller and a check valve in sequence, and the check valve is connected to the cooler. 11.The thermal management control system for new energy vehicle battery fast charging scenario of claim 10, wherein, A first cooling solenoid valve and a first electronic expansion valve are provided between the cooler and the heat exchanger, and a second electronic expansion valve is provided between the cooler, the air-cooled pump, and the check valve.

12. The thermal management control system for new energy vehicle battery fast charging scenario according to claim 10, wherein, A pump is installed between the battery casing and the input end of the cooler, and a second cooling solenoid valve is installed between the output end of the cooler and the battery casing.

13. The thermal management control system for new energy vehicle battery fast charging scenario according to claim 9, wherein, The thermal management control on factor is represented as: In the formula, β i P represents the output quantity. i Let β represent the output quantity under the i-th fuzzy control rule. i The membership function value.

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