Power battery direct cooling system and temperature control method

Abstract

The invention provides a power battery direct cooling system and a temperature control method, the system comprises at least one direct cooling unit, each unit comprises a direct cooling module in contact with one side of a battery cell, a cold plate and a flow control valve are arranged in the module, and a refrigerant circulates through the cold plate. The method comprises the following steps: establishing a relation model of a battery cell temperature change rate and a water pipe diameter variation, formulating a water pipe diameter adjustment rule based on temperature, and establishing a model of a flow control valve adjustment degree and a water pipe diameter adjustment parameter according to the water pipe diameter adjustment rule so as to realize accurate control of the battery temperature. The temperature control efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a power battery direct cooling system and a temperature control method. Background Art

[0002] The most common direct cooling technology at present is bottom-type refrigerant direct cooling technology, which has the following problems: (1) Uneven temperature distribution: Traditional bottom-type refrigerant direct cooling technology may cause uneven temperature distribution of individual cells. The cooling medium can only exchange heat through the bottom of the cell, which limits the contact area between the cooling medium and the cell, resulting in low heat exchange efficiency, and low thermal conductivity in the height direction of the cell, resulting in a large difference between the top temperature and the internal temperature of the cell, affecting the performance and life of the battery; traditional bottom-type refrigerant direct cooling technology will also cause uneven temperature distribution of the battery pack as a whole. The series flow channel causes the temperature difference of the cell near the inlet and outlet of the cold plate to be too large, making it difficult for the battery pack to meet the requirements of high-power discharge or charging, affecting the charging performance and user experience of the battery. (2) Safety issues: The cooling response speed of the bottom-type cooling method is slow, especially when the battery is discharged or charged at high power, it is often unable to reduce the cell temperature in time, increasing the risk of thermal runaway. When the battery is in thermal runaway or overheating, the bottom-type cooling method may not be able to reduce the cell temperature in time, resulting in increased safety hazards, such as fire or explosion. Summary of the invention

[0003] In view of this, an embodiment of the present application provides a power battery direct cooling system and a temperature control method, which can improve the temperature control efficiency.

[0004] The technical solution of the embodiment of the present application is implemented as follows: In a first aspect, an embodiment of the present application provides a power battery direct cooling system, the system comprising: At least one direct cooling unit is arranged in sequence, each of the at least one direct cooling unit comprises a direct cooling module and a battery cell, the direct cooling module is arranged on one side of the battery cell and contacts the side, and the other side of the battery cell of the current direct cooling unit in the at least one direct cooling unit contacts the direct cooling module of the next direct cooling unit; The direct cooling module includes a cold plate and a flow control valve arranged at the cold plate inlet, and the cold plate is hollow inside. When working, the refrigerant enters the cold plate through the cold plate inlet and flows out from the cold plate outlet.

[0005] In a second aspect, an embodiment of the present application further provides a power battery temperature control method, the method comprising: Based on the relationship between the battery core temperature and the refrigerant flow rate, a mathematical model of the first relationship between the battery core temperature change rate and the water pipe diameter change amount is constructed; Determine a water pipe diameter adjustment rule based on temperature based on the relational mathematical model, wherein the water pipe diameter adjustment rule based on temperature includes a water pipe diameter adjustment parameter; A second mathematical model of the relationship between the regulation degree of the flow control valve and the water pipe diameter adjustment parameter is constructed, and the flow control valve is controlled to perform temperature control based on the second mathematical model of the relationship.

[0006] In a third aspect, an embodiment of the present application further provides a power battery temperature control device, the device comprising: A construction module, for constructing a first relationship mathematical model between the battery core temperature change rate and the water pipe diameter change amount based on the relationship between the battery core temperature and the refrigerant flow rate; A determination module, configured to determine a water pipe diameter adjustment rule based on temperature based on the relational mathematical model, wherein the water pipe diameter adjustment rule based on temperature includes a water pipe diameter adjustment parameter; The control module is used to construct a second relationship mathematical model between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, and control the flow control valve to perform temperature control based on the second relationship mathematical model.

[0007] In a fourth aspect, an embodiment of the present application further provides an electronic device, comprising: a processor, a storage medium and a bus, wherein the storage medium stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor communicates with the storage medium through the bus, and the processor executes the machine-readable instructions to execute the power battery temperature control method described in any one of the first aspects.

[0008] In a fifth aspect, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the power battery temperature control method described in any one of the first aspects is executed.

[0009] The embodiments of the present application have the following beneficial effects: Through the close contact design between the direct cooling module and the battery cell, and the circulation of the refrigerant inside the cold plate, the system can achieve efficient heat dissipation of the battery cell, quickly remove the heat generated by the battery cell, and prevent the battery cell from overheating. Using the mathematical model of the first relationship between the battery cell temperature and the refrigerant flow rate, the refrigerant flow rate can be accurately calculated and adjusted to control the temperature change rate of the battery cell. Combined with the temperature-based water pipe diameter adjustment rule, the battery cell temperature can be accurately controlled to ensure that the battery cell operates within the optimal temperature range. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0011] Figure 1 is a structural schematic diagram of a power battery direct cooling system provided in an embodiment of the present application; Figure 2 It is a flowchart of steps S201-S203 provided in an embodiment of the present application; Figure 3 This is a schematic diagram of the water pipe diameter adjustment provided in an embodiment of the present application; Figure 4 It is a flowchart of steps S401-S402 provided in an embodiment of the present application; Figure 5 is a structural schematic diagram of a power battery temperature control device provided in an embodiment of the present application; Figure 6 It is a schematic diagram of the composition structure of the electronic device provided in the embodiment of the present application. DETAILED DESCRIPTION

[0012] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art can add one or more other operations to the flowchart under the guidance of the content of the present application, or remove one or more operations from the flowchart.

[0013] In the following description, reference is made to “some embodiments”, which describe a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0014] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0015] In the following description, the terms "first\second\third" involved are merely used to distinguish similar objects and do not represent a specific ordering of the objects. It can be understood that "first\second\third" can be interchanged with a specific order or sequence where permitted, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0016] It should be noted that the term "comprising" will be used in the embodiments of the present application to indicate the existence of the features declared thereafter, but does not exclude the addition of other features.

[0017] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0018] See also Figure 1 , Figure 1 is a schematic diagram of the structure of the power battery direct cooling system provided in the embodiment of the present application, such as Figure 1 As shown, the system comprises: At least one direct cooling unit is arranged in sequence, each of the at least one direct cooling unit comprises a direct cooling module and a battery cell 3, the direct cooling module is arranged on one side of the battery cell 3 and contacts the side, and the other side of the battery cell 3 of the current direct cooling unit of the at least one direct cooling unit contacts the direct cooling module of the next direct cooling unit; The direct cooling module includes a cold plate 1 and a flow control valve 2 arranged at the inlet of the cold plate 1. The cold plate 1 is hollow inside. When working, the refrigerant enters the cold plate 1 through the inlet of the cold plate 1 and flows out from the outlet of the cold plate 1.

[0019] The system consists of at least one direct cooling unit, which are arranged in sequence to form a stacked structure. This design makes the cooling of the entire battery pack more uniform and efficient. Each direct cooling unit includes a direct cooling module and a battery cell 3. The direct cooling module is designed to be on one side of the battery cell 3 and in close contact with it, ensuring that heat can be directly transferred from the battery cell 3 to the direct cooling module, reducing thermal resistance and improving cooling efficiency. The other side of the battery cell 3 of the current direct cooling unit is in contact with the direct cooling module of the next direct cooling unit. This design makes both sides of the battery cell 3 contact with the direct cooling unit, and the arrangement of direct cooling unit-battery cell 3-direct cooling unit-battery cell 3-direct cooling unit can utilize the direct cooling module as efficiently as possible.

[0020] The core component of the direct cooling module is the cold plate 1, which is hollow inside and used to circulate the refrigerant. The cold plate 1 has good thermal conductivity and sealing to ensure that the refrigerant will not leak when circulating inside, and can effectively take away the heat generated by the battery cell 3. A flow control valve 2 is provided at the inlet of the cold plate 1 to adjust the flow of the refrigerant entering the cold plate 1. This design enables the system to flexibly adjust the cooling intensity according to different working conditions and cooling requirements to achieve the best cooling effect.

[0021] During operation, the refrigerant enters the cold plate 1 through the cold plate 1 inlet, circulates in the cold plate 1, absorbs the heat generated by the battery cells 3, and then flows out from the cold plate 1 outlet to enter the next stage of cooling cycle or recycling. Through the continuous flow of the refrigerant and heat exchange, the entire battery pack can be maintained in a relatively stable temperature range, thereby extending the battery life and improving the safety of the system.

[0022] The above power battery direct cooling system has the following beneficial effects: Efficient cooling: The close contact between the direct cooling module and the battery cell 3 reduces thermal resistance and improves cooling efficiency. Flexibility: The setting of the flow control valve 2 enables the system to adjust the cooling intensity according to actual needs. Compactness: The stacked structural design makes the entire system more compact and saves space. In summary, this power battery direct cooling system provides a reliable and efficient cooling solution for power battery packs through its unique design and efficient working principle.

[0023] In some embodiments, the flow control valve 2 corresponding to each cold plate 1 is independently controlled, and the outlets of each cold plate 1 are connected in series to form a drain pipe 4 .

[0024] Here, each cold plate 1 is equipped with an independent flow control valve 2, which can independently adjust the flow of refrigerant entering each cold plate 1 according to the specific cooling requirements of the battery pack. This design ensures that the system can achieve precise flow control according to the actual temperature distribution and cooling requirements of the battery cells 3, thereby optimizing the cooling effect.

[0025] The outlets of each cold plate 1 are connected in series to eventually form a drain pipe 4. This design allows the refrigerant to be uniformly discharged from the system through the drain pipe 4 after completing heat exchange and flowing out of the cold plate 1. The drain pipe 4 is not only responsible for collecting and discharging waste liquid in the cooling system, but also simplifies the system layout, reduces connection points and potential leakage risks.

[0026] The design of the drain pipe 4 also takes into account the maintenance and overhaul of the cooling system. Through the drain pipe 4, the refrigerant in the system can be easily drained for cleaning, replacement or repair. At the same time, the drain pipe 4 is also convenient for monitoring and detecting the operating status of the cooling system, and timely discovering and solving problems.

[0027] Based on the power battery direct cooling system, the present application also provides a power battery temperature control method, see Figure 2 , Figure 2 is a flow chart of steps S201-S203 of the power battery temperature control method provided in the embodiment of the present application, which will be combined with Figure 2 Steps S201-S203 are shown for explanation.

[0028] In step S201, a first relationship mathematical model between the battery core temperature change rate and the water pipe diameter change amount is constructed based on the relationship between the battery core temperature and the refrigerant flow rate.

[0029] In step S202, a temperature-based water pipe diameter adjustment rule is determined based on the relational mathematical model, and the temperature-based water pipe adjustment rule includes a water pipe diameter adjustment parameter.

[0030] In step S203, a second mathematical model of the relationship between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter is constructed, and the flow control valve is controlled to perform temperature control based on the second mathematical model of the relationship.

[0031] The method aims to achieve precise control of the temperature of the power battery pack by adjusting the diameter of the water pipe in the cooling system and the adjustment degree of the flow control valve. By constructing and applying two key mathematical models, namely the first relationship mathematical model between the rate of change of battery cell temperature and the change in water pipe diameter, and the second relationship mathematical model between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, dynamic adjustment and optimization of the cooling system are achieved.

[0032] First, it is necessary to collect the temperature change data of the battery cell under different refrigerant flow rates. This data may be obtained through experiments or simulations. Based on the collected data, a mathematical model between the battery cell temperature change rate and the change in water pipe diameter is constructed using statistical or machine learning methods. This model describes how the battery cell temperature will respond when the water pipe diameter changes.

[0033] Based on the mathematical model constructed in the first step, a set of temperature-based water pipe diameter adjustment rules are determined. These rules define how the diameter of the water pipe should be adjusted to achieve the desired cooling effect at different temperatures or temperature change rates. In the adjustment rules, the water pipe diameter adjustment parameters are set, which will serve as the basis for subsequent control of the flow control valve.

[0034] Using the collected data, a mathematical model between the flow control valve adjustment degree and the water pipe diameter adjustment parameter is constructed. This model describes how to change the effective diameter (or flow resistance) of the water pipe by adjusting the opening of the flow control valve, thereby affecting the cooling effect.

[0035] During the operation of the power battery pack, the temperature of the battery cell is monitored in real time. Based on the real-time monitored temperature data, the water pipe diameter parameter that should be adjusted is first calculated, and then the calculated water pipe diameter adjustment parameter is converted into the adjustment degree of the flow control valve, and the valve is controlled to make corresponding adjustments. After that, the battery cell temperature is continuously monitored, and the control strategy is fine-tuned according to the feedback results to ensure that the battery pack always remains within the optimal operating temperature range.

[0036] The above method achieves precise control of battery pack temperature by constructing a mathematical model and associating the relationship between different parameters. The parameters of the cooling system can be dynamically adjusted according to the real-time temperature status of the battery pack to ensure the maximum cooling effect. By optimizing the operating parameters of the cooling system, unnecessary energy consumption is reduced and the energy efficiency of the system is improved. Accurate temperature control helps to extend the service life of the battery pack and improve the overall reliability of electric vehicles.

[0037] In a possible implementation, establishing a mathematical model of the water cooling plate and the flow of the refrigerant requires considering the basic equations of fluid mechanics and the influence of heat exchange. The following is a simplified model that describes the basic relationship between the water cooling plate and the flow of the refrigerant: The mass conservation equation: ; Among them, ρ is the density of the refrigerant, v is the flow rate of the refrigerant, and t is time.

[0038] Momentum conservation equation: ; Where p is the pressure, μ is the dynamic viscosity of the refrigerant, and g is the acceleration due to gravity; Energy conservation equation: ; Among them, c p is the constant-pressure specific heat capacity of the refrigerant, k is the thermal conductivity of the refrigerant, and Q is the heat source term per unit volume, such as the amount of heat absorbed by the refrigerant.

[0039] On the boundary of the water-cooled plate surface, considering the heat exchange and mass transfer between the refrigerant and the water-cooled plate, the boundary condition of convection heat transfer can be adopted: q=h(T 冷板 -T 冷媒 ); ; Where q is the heat flux, h is the convective heat transfer coefficient, T 冷板 is the surface temperature of the cooling plate, T 冷媒 is the temperature of the refrigerant, m is the mass flow rate, v n is the normal velocity of the refrigerant at the boundary.

[0040] Establish a heat exchange model between the battery cell and the water cooling plate: Use Fourier's law of heat conduction to describe the heat transfer process between the battery cell and the water cooling plate: ; Among them, q 传导 is the heat transfer rate per unit area per unit time, k is the thermal conductivity of the material, A is the heat transfer area, is the temperature gradient.

[0041] The process of heat transfer through convection between the battery cell and the water cooling plate is described using Newton's law of cooling: ; Where qconvection is the heat transfer rate per unit time, h is the convection heat transfer coefficient, A is the heat transfer area, T 芯 is the cell surface temperature, T 冷媒 is the temperature of the cooling medium.

[0042] The relationship between heat and temperature change can be expressed as: ; Where Q is the amount of heat absorbed or released, m is the mass of the object, c is the specific heat capacity, and a is the temperature change.

[0043] Modeling the relationship between temperature and flow: Use the above model to establish the cell temperature T cell The relationship between the refrigerant flow rate q and f (T cell )=q, and based on the experimental data and the optimal mathematical model f(q)=D using regression analysis, a mathematical model f(a)=ΔD is established to establish the relationship between the temperature change a of the battery cell and the change ΔD in the water pipe diameter.

[0044] In one possible implementation, see Figure 3 , Figure 3 This is a schematic diagram of the water pipe diameter adjustment provided in the embodiment of the present application, such as Figure 3As shown, the temperature-based water pipe diameter adjustment rule includes: Assume the initial water pipe diameter is D, and set the target temperature range T min ~T max , the temperature change is a, the increase in tube diameter is ΔD1, ΔD2, and the decrease in tube diameter is ΔD3, ΔD4, where ΔD1>ΔD2, ΔD3>ΔD4; Determine whether T cell ≤T max If not, determine whether T cell -T max ≥a, if yes, increase the tube diameter to D + ΔD1 and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max If not, determine whether T cell -T max ≥a, if not, increase the tube diameter to D + ΔD2, and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max , if so, determine whether T cell ≥T min If not, determine whether T min -T cell ≥a, if yes, reduce the tube diameter to D-ΔD3 and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max , if so, determine whether T cell ≥T min If not, determine whether T min -T cell ≥a, if not, reduce the tube diameter to D-ΔD4 and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max , if so, determine whether T cell ≥T min If so, the inlet of the cold plate is closed by the flow control valve, and the diameter D=0.

[0045] In some embodiments, the change in the diameter of the water pipe calculated using f(a)=ΔD is used to send a signal to the flow control valve. The unit change in valve opening can be set to x, the adjustment degree is k, and a k=ΔD / x mathematical model is established. The opening or closing degree k of the water pipe is controlled in real time to change D to adjust the flow of the cooling medium. This can be achieved by controlling the valve. In some embodiments, see Figure 4 , Figure 4 It is a flowchart of steps S401-S402 provided in an embodiment of the present application. The method also includes steps S401-S402, which will be described in combination with each step.

[0046] In step S401, the temperature of the battery cell is monitored.

[0047] In step S402, if the control effect of the temperature control does not meet the set requirements, the first relationship mathematical model is corrected.

[0048] During the entire battery pack operation, the temperature of the battery cell is continuously and in real time monitored. The effect of temperature control is evaluated according to preset evaluation criteria or indicators (such as temperature fluctuation range, time to reach target temperature, number of over-temperatures, etc.). These criteria or indicators should be set based on the performance requirements, safety considerations and user expectations of the battery pack. Compare the actual control effect with the set requirements. If the control effect meets the requirements, continue to control the temperature according to the current control strategy; if the control effect does not meet the requirements, the first relationship mathematical model needs to be modified. Usually the following steps are involved: Data collection: Re-collect the temperature change data of the battery cells under different refrigerant flow rates and water pipe diameters. These data may include new experimental data or monitoring data from actual operation.

[0049] Model analysis: Conduct in-depth analysis of the collected data to identify the reasons why the control effect does not meet the requirements. This may be due to inaccurate model parameters, unreasonable model structure, or unmodeled dynamic characteristics of the system.

[0050] Model modification: Based on the analysis results, the first relationship mathematical model is modified. This may include adjusting model parameters, modifying model structure, or introducing new variables and parameters. The modified model should be able to more accurately describe the relationship between the rate of change of battery cell temperature and the change in water pipe diameter.

[0051] Verification and testing: Apply the revised model to the actual control system for verification and testing. The effectiveness of the model revision can be evaluated by comparing the control effects before and after the revision.

[0052] In summary, the embodiments of the present application have the following beneficial effects: (1) Improve control accuracy: By constructing a mathematical model of the first relationship between the rate of change of battery cell temperature and the change in water pipe diameter, this method can accurately calculate and adjust the water pipe diameter to achieve fine control of battery cell temperature. This helps maintain the battery cell temperature within the optimal operating range, reduce temperature fluctuations, and improve system stability.

[0053] (2) Dynamic adaptability: This method can adjust the water pipe diameter in real time according to actual temperature changes, quickly respond to temperature changes, effectively prevent overheating or overcooling of the battery cell, and ensure continuous optimization of battery performance and safety.

[0054] (3) Optimizing the cooling system: By constructing a mathematical model of the second relationship between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, this method can accurately control the flow of the cooling system and reduce unnecessary energy consumption. At the same time, by reasonably adjusting the water pipe diameter, the flow path and speed of the coolant are optimized, the cooling efficiency is improved, and energy consumption is further reduced.

[0055] In summary, this power battery temperature control method has shown significant beneficial effects in improving control accuracy, energy efficiency, battery life, safety and user experience, and is of great significance to promoting the advancement and popularization of new energy vehicle technology.

[0056] Based on the same inventive concept, an embodiment of the present application also provides a power battery temperature control device corresponding to the power battery temperature control method in the first embodiment. Since the principle of solving the problem by the device in the embodiment of the present application is similar to that of the above-mentioned power battery temperature control method, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0057] like Figure 5 As shown, Figure 5 : is a schematic diagram of the structure of a power battery temperature control device 500 provided in an embodiment of the present application. The power battery temperature control device 500 includes: A construction module 501 is used to construct a first relationship mathematical model between the battery core temperature change rate and the water pipe diameter change amount based on the relationship between the battery core temperature and the refrigerant flow rate; A determination module 502 is used to determine a water pipe diameter adjustment rule based on temperature based on the relationship mathematical model, wherein the water pipe diameter adjustment rule based on temperature includes a water pipe diameter adjustment parameter; The control module 503 is used to construct a second relationship mathematical model between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, and control the flow control valve to perform temperature control based on the second relationship mathematical model.

[0058] Those skilled in the art should understand that Figure 5 The functions implemented by each unit in the power battery temperature control device 500 shown can be understood by referring to the relevant description of the power battery temperature control method described above. Figure 5 The functions of each unit in the power battery temperature control device 500 shown can be implemented by a program running on a processor, or can be implemented by a specific logic circuit.

[0059] In a possible implementation, the temperature-based water pipe diameter adjustment rule includes: Assume the initial water pipe diameter is D, and set the target temperature range T min ~T max , the temperature change is a, the increase in tube diameter is ΔD1, ΔD2, and the decrease in tube diameter is ΔD3, ΔD4, where ΔD1>ΔD2, ΔD3>ΔD4; Determine whether T cell ≤T max If not, determine whether T cell -T max ≥a, if yes, increase the tube diameter to D + ΔD1 and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max If not, determine whether T cell -T max ≥a, if not, increase the tube diameter to D + ΔD2, and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max , if so, determine whether T cell ≥T min If not, determine whether T min -T cell ≥a, if yes, reduce the tube diameter to D-ΔD3 and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max , if so, determine whether T cell ≥T min If not, determine whether T min -T cell ≥a, if not, reduce the tube diameter to D-ΔD4 and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max , if so, determine whether T cell ≥T min If so, the inlet of the cold plate is closed by the flow control valve, and the diameter D=0.

[0060] In a possible implementation manner, the first relationship mathematical model is f(a)=ΔD; Wherein, a is the temperature change of the battery cell, and ΔD is the change in the diameter of the water pipe; The first mathematical model of the relationship is through the cell temperature T cell The relationship between the refrigerant flow rate q and f (T cell) = q, obtained based on experimental data and regression analysis; The relationship between the cold plate and the refrigerant flow includes: , where ρ is the density of the refrigerant, v is the flow rate of the refrigerant, and t is the time; ; Where p is the pressure, μ is the dynamic viscosity of the refrigerant, and g is the acceleration due to gravity; , where c p is the constant pressure specific heat capacity of the refrigerant, k is the thermal conductivity of the refrigerant, and Q is the heat source term per unit volume; q=h(T 冷板 -T 冷媒 ), ; where q is the heat flux density, h is the convective heat transfer coefficient, T 冷板 is the surface temperature of the cooling plate, T 冷媒 is the temperature of the refrigerant, m is the mass flow rate, is the normal velocity of the refrigerant at the boundary; The heat transfer process between the battery cell and the water cooling plate: , where q 传导 is the heat transfer rate per unit area per unit time, k is the thermal conductivity of the material, A is the heat transfer area, is the temperature gradient; The process of heat transfer through convection between the battery cell and the cold plate: , where qconvection is the heat transfer rate per unit time, h is the convection heat transfer coefficient, A is the heat transfer area, T 芯 is the cell surface temperature, T 冷媒 is the temperature of the cooling medium; The relationship between heat and temperature change is expressed as: ; where Q is the amount of heat absorbed or released, m is the mass of the object, c is the specific heat capacity, and a is the temperature change.

[0061] In a possible implementation manner, the second relationship mathematical model is k=ΔD / x; Among them, x is the unit change of the opening of the flow control valve, k is the adjustment degree of the flow control valve, and ΔD is the change of the water pipe diameter.

[0062] In a possible implementation, the control module 503 further includes: Monitoring the temperature of the battery cell; If the control effect of the temperature control does not meet the set requirements, the first relationship mathematical model is corrected.

[0063] The above power battery temperature control device has the following beneficial effects: (1) Improve control accuracy: By constructing a mathematical model of the first relationship between the rate of change of battery cell temperature and the change in water pipe diameter, this method can accurately calculate and adjust the water pipe diameter to achieve fine control of battery cell temperature. This helps maintain the battery cell temperature within the optimal operating range, reduce temperature fluctuations, and improve system stability.

[0064] (2) Dynamic adaptability: This method can adjust the water pipe diameter in real time according to actual temperature changes, quickly respond to temperature changes, effectively prevent overheating or overcooling of the battery cell, and ensure continuous optimization of battery performance and safety.

[0065] (3) Optimizing the cooling system: By constructing a mathematical model of the second relationship between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, this method can accurately control the flow of the cooling system and reduce unnecessary energy consumption. At the same time, by reasonably adjusting the water pipe diameter, the flow path and speed of the coolant are optimized, the cooling efficiency is improved, and energy consumption is further reduced.

[0066] In summary, this power battery temperature control method has shown significant beneficial effects in improving control accuracy, energy efficiency, battery life, safety and user experience, and is of great significance to promoting the advancement and popularization of new energy vehicle technology.

[0067] like Figure 6 As shown, Figure 6 The present invention provides a schematic diagram of the structure of an electronic device 600, wherein the electronic device 600 includes: A processor 601, a storage medium 602 and a bus 603, wherein the storage medium 602 stores machine-readable instructions executable by the processor 601. When the electronic device 600 is running, the processor 601 communicates with the storage medium 602 via the bus 603, and the processor 601 executes the machine-readable instructions to perform the steps of the power battery temperature control method described in the embodiment of the present application.

[0068] In actual application, the components in the electronic device 600 are coupled together via the bus 603. It is understood that the bus 603 is used to realize the connection and communication between these components. In addition to the data bus, the bus 603 also includes a power bus, a control bus, and a status signal bus. However, for the sake of clarity, Figure 6 Various buses are labeled as bus 603.

[0069] The electronic device has the following beneficial effects: (1) Improve control accuracy: By constructing a mathematical model of the first relationship between the rate of change of battery cell temperature and the change in water pipe diameter, this method can accurately calculate and adjust the water pipe diameter to achieve fine control of battery cell temperature. This helps maintain the battery cell temperature within the optimal operating range, reduce temperature fluctuations, and improve system stability.

[0070] (2) Dynamic adaptability: This method can adjust the water pipe diameter in real time according to actual temperature changes, quickly respond to temperature changes, effectively prevent overheating or overcooling of the battery cell, and ensure continuous optimization of battery performance and safety.

[0071] (3) Optimizing the cooling system: By constructing a mathematical model of the second relationship between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, this method can accurately control the flow of the cooling system and reduce unnecessary energy consumption. At the same time, by reasonably adjusting the water pipe diameter, the flow path and speed of the coolant are optimized, the cooling efficiency is improved, and energy consumption is further reduced.

[0072] In summary, this power battery temperature control method has shown significant beneficial effects in improving control accuracy, energy efficiency, battery life, safety and user experience, and is of great significance to promoting the advancement and popularization of new energy vehicle technology.

[0073] The embodiment of the present application further provides a computer-readable storage medium, which stores executable instructions. When the executable instructions are executed by at least one processor 601, the power battery temperature control method described in the embodiment of the present application is implemented.

[0074] In some embodiments, the storage medium can be a magnetic random access memory (FRAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory, a magnetic surface storage, an optical disk, or a compact disc read-only memory (CD-ROM); it can also be various devices including one or any combination of the above memories.

[0075] In some embodiments, executable instructions may be in the form of a program, software, software module, script or code, written in any form of programming language (including compiled or interpreted languages, or declarative or procedural languages), and may be deployed in any form, including as a stand-alone program or as a module, component, subroutine or other unit suitable for use in a computing environment.

[0076] As an example, executable instructions may, but do not necessarily, correspond to a file in a file system, may be stored as part of a file that stores other programs or data, for example, in one or more scripts in a HyperText Markup Language (HTML) document, in a single file dedicated to the program in question, or in multiple coordinated files (for example, files storing one or more modules, subroutines, or code portions).

[0077] By way of example, executable instructions may be deployed to be executed on one computing device, or on multiple computing devices located at one site, or on multiple computing devices distributed across multiple sites and interconnected by a communication network.

[0078] The computer-readable storage medium has the following advantages: (1) Improve control accuracy: By constructing a mathematical model of the first relationship between the rate of change of battery cell temperature and the change in water pipe diameter, this method can accurately calculate and adjust the water pipe diameter to achieve fine control of battery cell temperature. This helps maintain the battery cell temperature within the optimal operating range, reduce temperature fluctuations, and improve system stability.

[0079] (2) Dynamic adaptability: This method can adjust the water pipe diameter in real time according to actual temperature changes, quickly respond to temperature changes, effectively prevent overheating or overcooling of the battery cell, and ensure continuous optimization of battery performance and safety.

[0080] (3) Optimizing the cooling system: By constructing a mathematical model of the second relationship between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, this method can accurately control the flow of the cooling system and reduce unnecessary energy consumption. At the same time, by reasonably adjusting the water pipe diameter, the flow path and speed of the coolant are optimized, the cooling efficiency is improved, and energy consumption is further reduced.

[0081] In summary, this power battery temperature control method has shown significant beneficial effects in improving control accuracy, energy efficiency, battery life, safety and user experience, and is of great significance to promoting the advancement and popularization of new energy vehicle technology.

[0082] In the several embodiments provided in the present application, it should be understood that the disclosed methods and electronic devices can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0083] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0084] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0085] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a platform server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard drives, ROM, RAM, magnetic disks, or optical disks.

[0086] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A power battery direct cooling system, characterized in that: The system comprises: At least one direct cooling unit is arranged in sequence, each of the at least one direct cooling unit comprises a direct cooling module and a battery cell, the direct cooling module is arranged on one side of the battery cell and contacts the side, and the other side of the battery cell of the current direct cooling unit in the at least one direct cooling unit contacts the direct cooling module of the next direct cooling unit; The direct cooling module includes a cold plate and a flow control valve arranged at the cold plate inlet, and the cold plate is hollow inside. When working, the refrigerant enters the cold plate through the cold plate inlet and flows out from the cold plate outlet.

2. The power battery direct cooling system according to claim 1, characterized in that: The flow control valve corresponding to each cold plate is independently controlled, and the outlets of each cold plate are connected in series to form a drain pipe.

3. A power battery temperature control method, characterized in that: The method comprises: Based on the relationship between the battery core temperature and the refrigerant flow rate, a mathematical model of the first relationship between the battery core temperature change rate and the water pipe diameter change amount is constructed; Determine a water pipe diameter adjustment rule based on temperature based on the relational mathematical model, wherein the water pipe diameter adjustment rule based on temperature includes a water pipe diameter adjustment parameter; A second mathematical model of the relationship between the regulation degree of the flow control valve and the water pipe diameter adjustment parameter is constructed, and the flow control valve is controlled to perform temperature control based on the second mathematical model of the relationship.

4. The method according to claim 3, characterized in that The temperature-based water pipe diameter adjustment rules include: Assume the initial water pipe diameter is D, and set the target temperature range T min ~T max , the temperature change is a, the increase in tube diameter is ΔD1, ΔD2, and the decrease in tube diameter is ΔD3, ΔD4, where ΔD1>ΔD2, ΔD3>ΔD4; Determine whether T cell ≤T max If not, determine whether T cell -T max ≥a, if yes, increase the tube diameter to D + ΔD1 and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max If not, determine whether T cell -T max ≥a, if not, increase the tube diameter to D + ΔD2, and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max , if so, determine whether T cell ≥T min If not, determine whether T min -T cell ≥a, if yes, reduce the tube diameter to D-ΔD3 and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max , if so, determine whether T cell ≥T min If not, determine whether T min -T cell ≥a, if not, reduce the tube diameter to D-ΔD4 and continue to monitor the cell temperature T cell ; Determine whether T cell ≤T max , if so, determine whether T cell ≥T min If so, the inlet of the cold plate is closed by the flow control valve, and the diameter D=0.

5. The method according to claim 3, characterized in that: The first relationship mathematical model is f(a)=ΔD; Wherein, a is the temperature change of the battery cell, and ΔD is the change in the diameter of the water pipe; The first mathematical model of the relationship is through the cell temperature T cell The relationship between the refrigerant flow rate q and f (T cell ) = q, obtained based on experimental data and regression analysis; The relationship between the cold plate and the refrigerant flow includes: , where ρ is the density of the refrigerant, v is the flow rate of the refrigerant, and t is the time; ; Where p is the pressure, μ is the dynamic viscosity of the refrigerant, and g is the acceleration due to gravity; , where c p is the constant pressure specific heat capacity of the refrigerant, k is the thermal conductivity of the refrigerant, and Q is the heat source term per unit volume; q=h(T 冷板 -T 冷媒 ), ; where q is the heat flux density, h is the convective heat transfer coefficient, T 冷板 is the surface temperature of the cooling plate, T 冷媒 is the temperature of the refrigerant, m is the mass flow rate, is the normal velocity of the refrigerant at the boundary; The heat transfer process between the battery cell and the water cooling plate: , where q 传导 is the heat transfer rate per unit area per unit time, k is the thermal conductivity of the material, A is the heat transfer area, is the temperature gradient; The process of heat transfer through convection between the battery cell and the cold plate: , where qconvection is the heat transfer rate per unit time, h is the convection heat transfer coefficient, A is the heat transfer area, T 芯 is the cell surface temperature, T 冷媒 is the temperature of the cooling medium; The relationship between heat and temperature change is expressed as: ; where Q is the amount of heat absorbed or released, m is the mass of the object, c is the specific heat capacity, and a is the temperature change.

6. The method according to claim 3, characterized in that: The second relationship mathematical model is k=ΔD / x; Among them, x is the unit change of the opening of the flow control valve, k is the adjustment degree of the flow control valve, and ΔD is the change of the water pipe diameter.

7. The method according to claim 3, characterized in that The method further comprises: Monitoring the temperature of the battery cell; If the control effect of the temperature control does not meet the set requirements, the first relationship mathematical model is corrected.

8. A power battery temperature control device, characterized in that: The device comprises: A construction module, for constructing a first relationship mathematical model between the battery core temperature change rate and the water pipe diameter change amount based on the relationship between the battery core temperature and the refrigerant flow rate; A determination module, configured to determine a water pipe diameter adjustment rule based on temperature based on the relational mathematical model, wherein the water pipe diameter adjustment rule based on temperature includes a water pipe diameter adjustment parameter; The control module is used to construct a second relationship mathematical model between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, and control the flow control valve to perform temperature control based on the second relationship mathematical model.

9. An electronic device, characterized in that: include: A processor, a storage medium and a bus, wherein the storage medium stores machine-readable instructions executable by the processor. When the electronic device is running, the processor communicates with the storage medium via the bus, and the processor executes the machine-readable instructions to execute the power battery temperature control method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the power battery temperature control method according to any one of claims 1 to 7 is executed.

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