A power battery direct cooling system and temperature control method

Abstract

The application provides a power battery direct cooling system and a temperature control method. The system comprises at least one direct cooling unit, each unit comprising a direct cooling module in contact with one side of an electric core, a built-in cold plate in the module and a flow control valve, and a refrigerant circulating through the cold plate. The method comprises: constructing a relationship model of the temperature change rate of the electric core and the diameter change amount of the water pipe, formulating a water pipe diameter adjustment rule based on the temperature, and constructing a model of the flow control valve adjustment degree and the water pipe diameter adjustment parameter based on the rule, so as to realize accurate control of the battery temperature. The application can improve the temperature control efficiency.

Description

Technical Field

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

[0002] The most common direct cooling technology currently is bottom-mounted refrigerant direct cooling technology, which has the following problems: (1) Uneven temperature distribution: Traditional bottom-mounted refrigerant direct cooling technology may lead to 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. In addition, the thermal conductivity in the height direction of the cell is low, which leads to a large difference between the temperature at the top of the cell and the internal temperature, affecting the performance and life of the battery. Traditional bottom-mounted refrigerant direct cooling technology will also lead to uneven temperature distribution of the battery pack as a whole. The series flow channels lead to an excessive temperature difference between the cells near the inlet and outlet of the cold plate, making it difficult for the battery pack to meet the needs 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-mounted cooling method is relatively slow. Especially when the battery is undergoing high-power discharge or charging, it often cannot reduce the cell temperature in time, increasing the risk of thermal runaway. When the battery undergoes thermal runaway or overheating, the bottom-mounted cooling method may not be able to reduce the cell temperature in time, leading to increased safety hazards, such as serious consequences such as fire or explosion. Summary of the Invention

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

[0004] The technical solution of this application embodiment is implemented as follows:

[0005] In a first aspect, embodiments of this application provide a direct cooling system for a power battery, the system comprising:

[0006] At least one direct cooling unit is arranged in sequence. Each direct cooling unit includes a direct cooling module and a battery cell. The direct cooling module is disposed on one side of the battery cell and is in contact with that side. The other side of the battery cell in the current direct cooling unit is in contact with the direct cooling module of the next direct cooling unit.

[0007] The direct cooling module includes a cold plate and a flow control valve installed at the inlet of the cold plate. The inside of the cold plate is hollow. During operation, the refrigerant enters the interior of the cold plate through the inlet and flows out from the outlet of the cold plate.

[0008] Secondly, embodiments of this application also provide a method for controlling the temperature of a power battery, the method comprising:

[0009] Based on the relationship between cell temperature and refrigerant flow rate, a mathematical model is constructed to establish the first relationship between the rate of change of cell temperature and the change in water pipe diameter.

[0010] Based on the aforementioned relational mathematical model, a temperature-based water pipe diameter adjustment rule is determined, which includes water pipe diameter adjustment parameters.

[0011] A second mathematical model is constructed to establish a relationship between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, and the flow control valve is controlled to perform temperature control based on the second mathematical model.

[0012] Thirdly, embodiments of this application also provide a power battery temperature control device, the device comprising:

[0013] The module is used to construct a mathematical model of the first relationship between the rate of change of battery cell temperature and the change in water pipe diameter, based on the relationship between battery cell temperature and refrigerant flow rate.

[0014] A determination module is used to determine a temperature-based water pipe diameter adjustment rule based on the relational mathematical model, wherein the temperature-based water pipe adjustment rule includes water pipe diameter adjustment parameters.

[0015] The control module is used to construct a second mathematical model of the relationship between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, and to control the flow control valve to perform temperature control based on the second mathematical model of the relationship.

[0016] Fourthly, embodiments of this application also provide an electronic device, including: 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 via the bus, and the processor executes the machine-readable instructions to perform the power battery temperature control method described in any of the first aspects.

[0017] Fifthly, embodiments of this application also provide a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the power battery temperature control method described in any one of the first aspects.

[0018] The embodiments of this application have the following beneficial effects:

[0019] Through a design that ensures close contact between the direct cooling module and the battery cell, and the circulation of refrigerant within the cold plate, this system achieves efficient heat dissipation from the battery cell, rapidly removing the heat generated and preventing overheating. Utilizing a mathematical model of the primary relationship between battery cell temperature and refrigerant flow rate, the refrigerant flow rate can be precisely calculated and adjusted, thereby controlling the rate of temperature change of the battery cell. Combined with temperature-based water pipe diameter adjustment rules, precise control of the battery cell temperature is achieved, ensuring that the battery cell operates within its optimal temperature range. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of the power battery direct cooling system provided in the embodiments of this application;

[0022] Figure 2 This is a flowchart illustrating steps S201-S203 provided in the embodiments of this application;

[0023] Figure 3 This is a schematic diagram illustrating the principle of water pipe diameter adjustment provided in an embodiment of this application;

[0024] Figure 4 This is a flowchart illustrating steps S401-S402 provided in the embodiments of this application;

[0025] Figure 5 This is a schematic diagram of the structure of the power battery temperature control device provided in the embodiments of this application;

[0026] Figure 6 This is a schematic diagram of the composition structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the accompanying drawings in this application are for illustrative and descriptive purposes only and are not intended to limit the scope of protection of this application. Furthermore, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may not be implemented in sequence, and steps without logical contextual relationships may be reversed or implemented simultaneously. In addition, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts.

[0028] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is 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.

[0029] Furthermore, the described embodiments are merely some, not all, of the embodiments of this application. The components of the embodiments of this application described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0030] In the following description, the terms "first, second, third" are used merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first, second, third" may be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.

[0031] It should be noted that the term "comprising" will be used in the embodiments of this application to indicate the presence of the features declared thereafter, but does not exclude the addition of other features.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application and is not intended to limit this application.

[0033] See Figure 1 , Figure 1 This is a schematic diagram of the structure of the direct cooling system for power batteries provided in the embodiments of this application, as shown below. Figure 1 As shown, the system includes:

[0034] At least one direct cooling unit is arranged in sequence. Each direct cooling unit includes a direct cooling module and a battery cell 3. The direct cooling module is disposed on one side of the battery cell 3 and is in contact with that side. The other side of the battery cell 3 in the current direct cooling unit is in contact with the direct cooling module of the next direct cooling unit.

[0035] The direct cooling module includes a cold plate 1 and a flow control valve 2 disposed at the inlet of the cold plate 1. The interior of the cold plate 1 is hollow. During operation, the refrigerant enters the interior of the cold plate 1 through the inlet of the cold plate 1 and flows out from the outlet of the cold plate 1.

[0036] The system consists of at least one direct-cooling unit, which are arranged sequentially to form a stacked structure. This design makes the cooling of the entire battery pack more uniform and efficient. Each direct-cooling unit contains 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 in the current direct-cooling unit is in contact with the direct-cooling module of the next direct-cooling unit. This design ensures that both sides of the battery cell 3 are in contact with the direct-cooling unit, and the arrangement of direct-cooling unit-cell 3-direct-cooling unit-cell 3-direct-cooling unit can utilize the direct-cooling module as efficiently as possible.

[0037] The core component of the direct-cooling module is the cold plate 1, which is hollow inside to allow refrigerant to flow. The cold plate 1 possesses excellent thermal conductivity and sealing properties to ensure no refrigerant leakage during internal circulation and to effectively remove the heat generated by the battery cell 3. A flow control valve 2 is installed at the inlet of the cold plate 1 to regulate the refrigerant flow rate entering the cold plate 1. This design allows the system to flexibly adjust the cooling intensity according to different operating conditions and cooling requirements to achieve optimal cooling performance.

[0038] During operation, the refrigerant enters the interior of the cold plate 1 through the inlet, circulates within the cold plate 1, absorbs the heat generated by the battery cells 3, and then flows out from the outlet of the cold plate 1 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 within a relatively stable temperature range, thereby extending the battery's lifespan and improving system safety.

[0039] The above-mentioned direct cooling system for power batteries has the following beneficial effects:

[0040] High-efficiency cooling: The close contact between the direct cooling module and cell 3 reduces thermal resistance and improves cooling efficiency. Flexibility: The flow control valve 2 allows 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 direct cooling system for power batteries, through its unique design and efficient operating principle, provides a reliable and efficient cooling solution for power battery packs.

[0041] 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.

[0042] Here, each cold plate 1 is equipped with an independent flow control valve 2. These valves can independently adjust the refrigerant flow into their respective cold plates 1 according to the specific cooling requirements of the battery pack. This design ensures that the system can achieve precise flow control based on the actual temperature distribution and cooling requirements of the battery cells 3, thereby optimizing the cooling effect.

[0043] The outlets of each cold plate 1 are connected in series to form a drain pipe 4. This design allows the refrigerant to be 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 not only collects and discharges waste liquid from the cooling system, but also simplifies the system layout and reduces connection points and potential leakage risks.

[0044] The design of drain pipe 4 also takes into account the maintenance and repair of the cooling system. Drain pipe 4 allows for easy emptying of the refrigerant from the system, facilitating cleaning, replacement, or repair operations. Simultaneously, drain pipe 4 also facilitates monitoring and detection of the cooling system's operating status, enabling timely identification and resolution of problems.

[0045] Based on the direct cooling system for power batteries, this application also provides a method for controlling the temperature of power batteries, see [link to relevant documentation]. Figure 2 , Figure 2 This is a flowchart illustrating steps S201-S203 of the power battery temperature control method provided in this application embodiment, which will be combined with... Figure 2 Steps S201-S203 will be explained as shown.

[0046] In step S201, a first mathematical model of the relationship between the cell temperature change rate and the water pipe diameter change is constructed based on the relationship between the cell temperature and the refrigerant flow rate.

[0047] 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 water pipe diameter adjustment parameters.

[0048] 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.

[0049] This method aims to achieve precise temperature control of the power battery pack by adjusting the diameter of the water pipes and the adjustment degree of the flow control valve in the cooling system. By constructing and applying two key mathematical models—a first mathematical model relating the cell temperature change rate to the water pipe diameter change, and a second mathematical model relating the flow control valve adjustment degree to the water pipe diameter adjustment parameter—dynamic adjustment and optimization of the cooling system are achieved.

[0050] First, it is necessary to collect data on the temperature changes of the battery cells under different refrigerant flow rates. This data can be obtained through experiments or simulations. Based on the collected data, a mathematical model is constructed using statistical or machine learning methods to relate the rate of temperature change of the battery cells to the change in the diameter of the water pipe. This model describes how the battery cell temperature will respond when the diameter of the water pipe changes.

[0051] Based on the mathematical model established in the first step, a set of temperature-based water pipe diameter adjustment rules are determined. These rules define how to adjust the water pipe diameter to achieve the desired cooling effect at different temperatures or rates of temperature change. The adjustment rules set water pipe diameter adjustment parameters, which will serve as the basis for subsequent control of flow control valves.

[0052] Using the collected data, a mathematical model was constructed relating the flow control valve's adjustment degree to the water pipe diameter adjustment parameter. This model describes how adjusting the opening degree of the flow control valve changes the effective diameter (or flow resistance) of the water pipe, thereby affecting the cooling effect.

[0053] During the operation of the power battery pack, the temperature of the battery cells is monitored in real time. Based on the real-time temperature data, the water pipe diameter parameter that should be adjusted is first calculated. Then, the calculated water pipe diameter adjustment parameter is converted into the adjustment degree of the flow control valve, and the valve is adjusted accordingly. Subsequently, the cell temperature is continuously monitored, and the control strategy is fine-tuned based on the feedback results to ensure that the battery pack is always kept within the optimal operating temperature range.

[0054] The above method achieves precise temperature control of the battery pack by constructing a mathematical model and relating different parameters. It dynamically adjusts the cooling system parameters based on the real-time temperature of the battery pack, ensuring maximum cooling efficiency. By optimizing the operating parameters of the cooling system, unnecessary energy consumption is reduced, improving system energy efficiency. Precise temperature control helps extend the battery pack's lifespan and improves the overall reliability of electric vehicles.

[0055] In one possible implementation, establishing a mathematical model of the water-cooled plate and refrigerant flow requires considering the fundamental equations of fluid mechanics and the effects of heat transfer. The following is a simplified model describing the basic relationship between the water-cooled plate and refrigerant flow:

[0056] mass conservation equation:

[0057] ;

[0058] Where ρ is the density of the refrigerant, v is the flow rate of the refrigerant, and t is time.

[0059] Momentum conservation equation:

[0060] ;

[0061] Where p is pressure, μ is the dynamic viscosity of the refrigerant, and g is the acceleration due to gravity;

[0062] Energy conservation equation:

[0063] ;

[0064] Among them, c p is the specific heat capacity at constant pressure of the refrigerant, k is the thermal conductivity of the refrigerant, and Q is the heat source term per unit volume, such as the heat absorbed by the refrigerant.

[0065] At the boundary of the water-cooled plate surface, considering the heat exchange and mass transfer between the refrigerant and the water-cooled plate, convective heat transfer boundary conditions can be adopted:

[0066] q=h(T) 冷板 -T 冷媒 );

[0067] ;

[0068] Where q is the heat flux density, h is the convective heat transfer coefficient, and T is the heat flux density. 冷板 It is the surface temperature of the cooling plate, T 冷媒 The temperature of the refrigerant is m, the mass flow rate is v. n It is the normal velocity of the refrigerant at the boundary.

[0069] Establish a heat exchange model between the battery cell and the water-cooled plate:

[0070] The heat transfer process between the battery cell and the water-cooled plate can be described using Fourier's law of thermal conduction:

[0071] ;

[0072] Where, q 传导It is the thermal conductivity of a unit area per unit time, where k is the thermal conductivity of the material, and A is the heat transfer area. It is a temperature gradient.

[0073] Newton's law of cooling describes the convective transfer of heat between the battery cell and the water-cooled plate:

[0074] ;

[0075] Where qconvective is the heat transfer rate per unit time, h is the convective heat transfer coefficient, A is the heat transfer area, and Tconvective is the heat transfer coefficient. 芯 It is the temperature of the cell surface, T 冷媒 It is the temperature of the cooling medium.

[0076] The relationship between heat and temperature change can be expressed as:

[0077] ;

[0078] Where Q is the heat absorbed or released, m is the mass of the object, c is the specific heat capacity, and a is the temperature change.

[0079] Establish a model for the relationship between temperature and flow rate: Use the above model to establish the cell temperature T cell The relationship between refrigerant flow rate q and f(T) cell Based on experimental data and using the optimal mathematical model f(q) = D through 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 in the diameter of the water pipe ΔD.

[0080] In one possible implementation, please refer to Figure 3 , Figure 3 This is a schematic diagram of the water pipe diameter adjustment principle provided in the embodiments of this application, such as... Figure 3 As shown, the temperature-based water pipe diameter adjustment rule includes:

[0081] Let the initial water pipe diameter be D, and set the target temperature range T. min ~T max Let the temperature change be a, the increase in pipe diameter be ΔD1 and ΔD2, and the decrease in pipe diameter be ΔD3 and ΔD4, where ΔD1 > ΔD2 and ΔD3 > ΔD4.

[0082] Determine if T cell ≤T max If not, determine whether it is T. cell -T max If ≥a, increase the tube diameter to D + ΔD1, and continue monitoring the cell temperature T. cell ;

[0083] Determine if T cell≤T max If not, determine whether it is T. cell -T max If ≥a, increase the tube diameter to D + ΔD2, and continue monitoring the cell temperature T. cell ;

[0084] Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If not, determine whether it is T. min -T cell If ≥a, reduce the tube diameter to D-ΔD3 and continue monitoring the cell temperature T. cell ;

[0085] Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If not, determine whether it is T. min -T cell ≥a, if not, reduce the tube diameter to D-ΔD4, and continue monitoring the cell temperature T. cell ;

[0086] Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If so, the inlet of the cold plate is closed by the flow control valve, and the diameter D=0.

[0087] In some embodiments, the change in water pipe diameter 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 as x, and the adjustment degree is k. A mathematical model of k = ΔD / x is established, and the opening or closing degree k of the water pipe is controlled in real time to change D, thereby adjusting the flow rate of the cooling medium. This can be achieved by controlling the valve.

[0088] In some embodiments, see Figure 4 , Figure 4 This is a flowchart illustrating steps S401-S402 provided in the embodiments of this application. The method further includes steps S401-S402, which will be explained in conjunction with each step.

[0089] In step S401, the temperature of the battery cell is monitored.

[0090] In step S402, if the temperature control effect does not meet the set requirements, the first relational mathematical model is corrected.

[0091] Throughout the battery pack's operation, the temperature of the cells is continuously and in real-time monitored. The effectiveness of temperature control is evaluated based on preset assessment criteria or indicators (such as temperature fluctuation range, time to reach target temperature, number of over-temperature cycles, etc.). These criteria or indicators should be set based on the battery pack's performance requirements, safety considerations, and user expectations. The actual control effect is compared with the set requirements. If the control effect meets the requirements, temperature control continues according to the current control strategy; if the control effect does not meet the requirements, the primary relationship mathematical model needs to be modified. This typically involves the following steps:

[0092] Data Collection: Re-collect temperature variation data of the battery cells under different refrigerant flow rates and water pipe diameters. This data may include new experimental data or monitoring data from actual operation.

[0093] Model analysis: 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 the existence of unmodeled dynamic characteristics in the system.

[0094] Model Revision: Based on the analysis results, the initial mathematical model of the relationship is revised. This may include adjusting model parameters, modifying the model structure, or introducing new variables and parameters. The revised model should be able to more accurately describe the relationship between the rate of change of cell temperature and the change in water pipe diameter.

[0095] Verification and Testing: The modified model is applied to a real-world control system for verification and testing. The effectiveness of the model modification is evaluated by comparing the control performance before and after the modification.

[0096] In summary, the embodiments of this application have the following beneficial effects:

[0097] (1) Improved control precision: By constructing a mathematical model of the first relationship between the rate of change of battery cell temperature and the change of water pipe diameter, this method can accurately calculate and adjust the water pipe diameter to achieve fine control of battery cell temperature. This helps to maintain the battery cell temperature within the optimal operating range, reduce temperature fluctuations, and improve system stability.

[0098] (2) Dynamic adaptability: This method can adjust the diameter of the water pipe in real time according to the actual temperature change, respond quickly to temperature changes, effectively prevent the battery cell from overheating or cooling, and ensure the continuous optimization of battery performance and safety.

[0099] (3) Optimize the cooling system: By constructing a second mathematical model relating the flow control valve's adjustment degree to the water pipe diameter adjustment parameter, this method can accurately control the flow rate of the cooling system and reduce unnecessary energy consumption. At the same time, by reasonably adjusting the water pipe diameter, the flow path and velocity of the coolant are optimized, improving cooling efficiency and further reducing energy consumption.

[0100] In summary, this power battery temperature control method demonstrates significant benefits in improving control accuracy, energy efficiency, battery life, safety, and user experience, and is of great importance to promoting the advancement and popularization of new energy vehicle technology.

[0101] Based on the same inventive concept, this 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 the device in this application is similar to the power battery temperature control method described above, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be described again.

[0102] like Figure 5 As shown, Figure 5 This is a schematic diagram of the structure of the power battery temperature control device 500 provided in an embodiment of this application. The power battery temperature control device 500 includes:

[0103] Module 501 is used to construct a mathematical model of the first relationship between the rate of change of battery cell temperature and the change in water pipe diameter based on the relationship between battery cell temperature and refrigerant flow rate.

[0104] The determination module 502 is used to determine a temperature-based water pipe diameter adjustment rule based on the relational mathematical model, wherein the temperature-based water pipe adjustment rule includes water pipe diameter adjustment parameters.

[0105] The control module 503 is used to construct a second mathematical model of the relationship between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, and to control the flow control valve to perform temperature control based on the second mathematical model of the relationship.

[0106] Those skilled in the art should understand that Figure 5 The functions of each unit in the power battery temperature control device 500 shown can be understood by referring to the relevant description of the aforementioned power battery temperature control method. Figure 5 The functions of each unit in the power battery temperature control device 500 shown can be realized by a program running on a processor or by a specific logic circuit.

[0107] In one possible implementation, the temperature-based water pipe diameter adjustment rule includes:

[0108] Let the initial water pipe diameter be D, and set the target temperature range T. min ~T max Let the temperature change be a, the increase in pipe diameter be ΔD1 and ΔD2, and the decrease in pipe diameter be ΔD3 and ΔD4, where ΔD1 > ΔD2 and ΔD3 > ΔD4.

[0109] Determine if T cell ≤T max If not, determine whether it is T. cell -T max If ≥a, increase the tube diameter to D + ΔD1, and continue monitoring the cell temperature T. cell ;

[0110] Determine if T cell ≤T max If not, determine whether it is T. cell -T max If ≥a, increase the tube diameter to D + ΔD2, and continue monitoring the cell temperature T. cell ;

[0111] Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If not, determine whether it is T. min -T cell If ≥a, reduce the tube diameter to D-ΔD3 and continue monitoring the cell temperature T. cell ;

[0112] Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If not, determine whether it is T. min -T cell ≥a, if not, reduce the tube diameter to D-ΔD4, and continue monitoring the cell temperature T. cell ;

[0113] Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If so, the inlet of the cold plate is closed by the flow control valve, and the diameter D=0.

[0114] In one possible implementation, the mathematical model of the first relationship is f(a) = ΔD;

[0115] Where a is the temperature change of the battery cell, and ΔD is the change in the diameter of the water pipe;

[0116] The first relationship mathematical model is based on the cell temperature T. cell The relationship between refrigerant flow rate q and f(T) cell The value of q is obtained from experimental data and regression analysis.

[0117] The relationship between the cold plate and the refrigerant flow includes:

[0118] Where ρ is the density of the refrigerant, v is the flow rate of the refrigerant, and t is time;

[0119] Where p is pressure, μ is the dynamic viscosity of the refrigerant, and g is the acceleration due to gravity.

[0120] , where c p is the specific heat capacity at constant pressure of the refrigerant, k is the thermal conductivity of the refrigerant, and Q is the heat source term per unit volume;

[0121] q=h(T) 冷板 -T 冷媒 ), Where q is the heat flux density, h is the convective heat transfer coefficient, and T is the heat transfer temperature. 冷板 It is the surface temperature of the cooling plate, T 冷媒 Where m is the temperature of the refrigerant, and m is the mass flow rate. It is the normal velocity of the refrigerant at the boundary;

[0122] The heat transfer process between the battery cell and the water-cooled plate: , where q 传导 It is the thermal conductivity of a unit area per unit time, where k is the thermal conductivity of the material, and A is the heat transfer area. It is a temperature gradient;

[0123] Heat is transferred through convection between the battery cell and the cold plate: Where qconvective is the heat transfer rate per unit time, h is the convective heat transfer coefficient, A is the heat transfer area, and Tconvective is the heat transfer area. 芯 It is the temperature of the cell surface, T 冷媒 It is the temperature of the cooling medium;

[0124] The relationship between heat and temperature change is expressed as: Where Q is the heat absorbed or released, m is the mass of the object, c is the specific heat capacity, and a is the temperature change.

[0125] In one possible implementation, the mathematical model of the second relationship is k = ΔD / x;

[0126] Where x is the unit change in the opening of the flow control valve, k is the adjustment degree of the flow control valve, and ΔD is the change in the diameter of the water pipe.

[0127] In one possible implementation, the control module 503 further includes:

[0128] The temperature of the battery cell is monitored;

[0129] If the temperature control effect does not meet the set requirements, the first relational mathematical model is modified.

[0130] The above-mentioned power battery temperature control device has the following beneficial effects:

[0131] (1) Improved control precision: By constructing a mathematical model of the first relationship between the rate of change of battery cell temperature and the change of water pipe diameter, this method can accurately calculate and adjust the water pipe diameter to achieve fine control of battery cell temperature. This helps to maintain the battery cell temperature within the optimal operating range, reduce temperature fluctuations, and improve system stability.

[0132] (2) Dynamic adaptability: This method can adjust the diameter of the water pipe in real time according to the actual temperature change, respond quickly to temperature changes, effectively prevent the battery cell from overheating or cooling, and ensure the continuous optimization of battery performance and safety.

[0133] (3) Optimize the cooling system: By constructing a second mathematical model relating the flow control valve's adjustment degree to the water pipe diameter adjustment parameter, this method can accurately control the flow rate of the cooling system and reduce unnecessary energy consumption. At the same time, by reasonably adjusting the water pipe diameter, the flow path and velocity of the coolant are optimized, improving cooling efficiency and further reducing energy consumption.

[0134] In summary, this power battery temperature control method demonstrates significant benefits in improving control accuracy, energy efficiency, battery life, safety, and user experience, and is of great importance to promoting the advancement and popularization of new energy vehicle technology.

[0135] like Figure 6 As shown, Figure 6 This is a schematic diagram of the composition structure of the electronic device 600 provided in the embodiments of this application. The electronic device 600 includes:

[0136] The device includes a processor 601, a storage medium 602, and a bus 603. The storage medium 602 stores machine-readable instructions that can be executed by the processor 601. When the electronic device 600 is running, the processor 601 communicates with the storage medium 602 via the bus 603. The processor 601 executes the machine-readable instructions to perform the steps of the power battery temperature control method described in the embodiments of this application.

[0137] In practical applications, the various components in the electronic device 600 are coupled together via a bus 603. It is understood that the bus 603 is used to achieve communication between these components. In addition to a data bus, the bus 603 also includes a power bus, a control bus, and a status signal bus. However, for clarity, in... Figure 6 The general designated all buses as Bus 603.

[0138] The above-mentioned electronic devices have the following beneficial effects:

[0139] (1) Improved control precision: By constructing a mathematical model of the first relationship between the rate of change of battery cell temperature and the change of water pipe diameter, this method can accurately calculate and adjust the water pipe diameter to achieve fine control of battery cell temperature. This helps to maintain the battery cell temperature within the optimal operating range, reduce temperature fluctuations, and improve system stability.

[0140] (2) Dynamic adaptability: This method can adjust the diameter of the water pipe in real time according to the actual temperature change, respond quickly to temperature changes, effectively prevent the battery cell from overheating or cooling, and ensure the continuous optimization of battery performance and safety.

[0141] (3) Optimize the cooling system: By constructing a second mathematical model relating the flow control valve's adjustment degree to the water pipe diameter adjustment parameter, this method can accurately control the flow rate of the cooling system and reduce unnecessary energy consumption. At the same time, by reasonably adjusting the water pipe diameter, the flow path and velocity of the coolant are optimized, improving cooling efficiency and further reducing energy consumption.

[0142] In summary, this power battery temperature control method demonstrates significant benefits in improving control accuracy, energy efficiency, battery life, safety, and user experience, and is of great importance to promoting the advancement and popularization of new energy vehicle technology.

[0143] This application also provides a computer-readable storage medium storing executable instructions. When the executable instructions are executed by at least one processor 601, the power battery temperature control method described in this application is implemented.

[0144] In some embodiments, the storage medium may 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 memory, an optical disc, or a compact disc read-only memory (CD-ROM), etc.; or it may be a device that includes one or any combination of the above-mentioned memories.

[0145] In some embodiments, executable instructions may take 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 standalone program or as a module, component, subroutine, or other unit suitable for use in a computing environment.

[0146] As an example, executable instructions may, but do not necessarily, correspond to files in the file system. They may be stored as part of a file that holds 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 collaborating files (e.g., a file that stores one or more modules, subroutines, or code sections).

[0147] As an example, executable instructions can be deployed to execute on a single computing device, or on multiple computing devices located in one location, or on multiple computing devices distributed across multiple locations and interconnected via a communication network.

[0148] The aforementioned computer-readable storage media have the following beneficial effects:

[0149] (1) Improved control precision: By constructing a mathematical model of the first relationship between the rate of change of battery cell temperature and the change of water pipe diameter, this method can accurately calculate and adjust the water pipe diameter to achieve fine control of battery cell temperature. This helps to maintain the battery cell temperature within the optimal operating range, reduce temperature fluctuations, and improve system stability.

[0150] (2) Dynamic adaptability: This method can adjust the diameter of the water pipe in real time according to the actual temperature change, respond quickly to temperature changes, effectively prevent the battery cell from overheating or cooling, and ensure the continuous optimization of battery performance and safety.

[0151] (3) Optimize the cooling system: By constructing a second mathematical model relating the flow control valve's adjustment degree to the water pipe diameter adjustment parameter, this method can accurately control the flow rate of the cooling system and reduce unnecessary energy consumption. At the same time, by reasonably adjusting the water pipe diameter, the flow path and velocity of the coolant are optimized, improving cooling efficiency and further reducing energy consumption.

[0152] In summary, this power battery temperature control method demonstrates significant benefits in improving control accuracy, energy efficiency, battery life, safety, and user experience, and is of great importance to promoting the advancement and popularization of new energy vehicle technology.

[0153] In the several embodiments provided in this application, it should be understood that the disclosed methods and electronic devices can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple units or components may be combined, or integrated into another system, or some features may be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the various components shown or discussed may be through some interfaces, and the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0154] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0155] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0156] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a platform server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, ROM, RAM, magnetic disks, or optical disks.

[0157] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for controlling the temperature of a power battery, characterized in that, This system is applied to a direct cooling system for power batteries, and includes: At least one direct cooling unit is arranged in sequence. Each direct cooling unit includes a direct cooling module and a battery cell. The direct cooling module is disposed on one side of the battery cell and is in contact with that side. The other side of the battery cell in the current direct cooling unit is in contact with the direct cooling module of the next direct cooling unit. The direct cooling module includes a cold plate and a flow control valve installed at the inlet of the cold plate. The inside of the cold plate is hollow. During operation, the refrigerant enters the interior of the cold plate through the inlet and flows out from the outlet of the cold plate. The method includes: Based on the relationship between cell temperature and refrigerant flow rate, a mathematical model is constructed to establish the first relationship between the rate of change of cell temperature and the change in water pipe diameter. Based on the aforementioned relational mathematical model, a temperature-based water pipe diameter adjustment rule is determined, which includes water pipe diameter adjustment parameters. A second mathematical model is constructed to establish a relationship between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, and the flow control valve is controlled to perform temperature control based on the second mathematical model. The temperature-based water pipe diameter adjustment rules include: Let the initial water pipe diameter be D, and set the target temperature range T. min ~T max Let the temperature change be a, the increase in pipe diameter be ΔD1 and ΔD2, and the decrease in pipe diameter be ΔD3 and ΔD4, where ΔD1 > ΔD2 and ΔD3 > ΔD4. Determine if T cell ≤T max If not, determine whether it is T. cell -T max If ≥a, increase the tube diameter to D + ΔD1, and continue monitoring the cell temperature T. cell ; Determine if T cell ≤T max If not, determine whether it is T. cell -T max If ≥a, increase the tube diameter to D + ΔD2, and continue monitoring the cell temperature T. cell ; Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If not, determine whether it is T. min -T cell If ≥a, reduce the tube diameter to D-ΔD3 and continue monitoring the cell temperature T. cell ; Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If not, determine whether it is T. min -T cell ≥a, if not, reduce the tube diameter to D-ΔD4, and continue monitoring the cell temperature T. cell ; Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If so, the inlet of the cold plate is closed by the flow control valve, and the diameter D=0; The mathematical model for the first relationship is f(a) = ΔD; Where a is the temperature change of the battery cell, and ΔD is the change in the diameter of the water pipe; The first relationship mathematical model is based on the cell temperature T. cell The relationship between refrigerant flow rate q and f(T) cell The value of q is obtained from 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 time; Where p is pressure, μ is the dynamic viscosity of the refrigerant, and g is the acceleration due to gravity. , where c p is the specific heat capacity at constant pressure of the refrigerant, k is the thermal conductivity of the refrigerant, and Q is the heat source term per unit volume. Indicates the temperature of the refrigerant; q=h(T) 冷板 -T 冷媒 ), Where q is the heat flux density, h is the convective heat transfer coefficient, and T is the heat transfer temperature. 冷板 It is the surface temperature of the cooling plate, T 冷媒 Where m is the temperature of the refrigerant, and m is the mass flow rate. It is the normal velocity of the refrigerant at the boundary; The heat transfer process between the battery cell and the water-cooled plate: , where q 传导 It is the thermal conductivity of a unit area per unit time, where k is the thermal conductivity of the material, and A is the heat transfer area. It is a temperature gradient; Heat is transferred through convection between the battery cell and the cold plate: ,in, It is the heat transfer rate per unit time, h is the convective heat transfer coefficient, A is the heat transfer area, and T is the heat transfer rate per unit time. 芯 It is the temperature of the cell surface, T 冷媒 It is the temperature of the cooling medium; The relationship between heat and temperature change is expressed as: Where Q is the heat absorbed or released, m is the mass of the object, c is the specific heat capacity, and a is the temperature change. The second relationship mathematical model is k = ΔD / x; Where x is the unit change in the opening of the flow control valve, k is the adjustment degree of the flow control valve, and ΔD is the change in the diameter of the water pipe.

2. The method according to claim 1, characterized in that, The method further includes: The temperature of the battery cell is monitored; If the temperature control effect does not meet the set requirements, the first relational mathematical model is modified.

3. A power battery temperature control device, characterized in that, This system is applied to a direct cooling system for power batteries, and includes: At least one direct cooling unit is arranged in sequence. Each direct cooling unit includes a direct cooling module and a battery cell. The direct cooling module is disposed on one side of the battery cell and is in contact with that side. The other side of the battery cell in the current direct cooling unit is in contact with the direct cooling module of the next direct cooling unit. The direct cooling module includes a cold plate and a flow control valve installed at the inlet of the cold plate. The inside of the cold plate is hollow. During operation, the refrigerant enters the interior of the cold plate through the inlet and flows out from the outlet of the cold plate. The device includes: The module is used to construct a mathematical model of the first relationship between the rate of change of battery cell temperature and the change in water pipe diameter, based on the relationship between battery cell temperature and refrigerant flow rate. A determination module is used to determine a temperature-based water pipe diameter adjustment rule based on the relational mathematical model, wherein the temperature-based water pipe adjustment rule includes water pipe diameter adjustment parameters. The control module is used to construct a second mathematical model of the relationship between the adjustment degree of the flow control valve and the water pipe diameter adjustment parameter, and to control the flow control valve to perform temperature control based on the second mathematical model of the relationship; The temperature-based water pipe diameter adjustment rules include: Let the initial water pipe diameter be D, and set the target temperature range T. min ~T max Let the temperature change be a, the increase in pipe diameter be ΔD1 and ΔD2, and the decrease in pipe diameter be ΔD3 and ΔD4, where ΔD1 > ΔD2 and ΔD3 > ΔD4. Determine if T cell ≤T max If not, determine whether it is T. cell -T max If ≥a, increase the tube diameter to D + ΔD1, and continue monitoring the cell temperature T. cell ; Determine if T cell ≤T max If not, determine whether it is T. cell -T max If ≥a, increase the tube diameter to D + ΔD2, and continue monitoring the cell temperature T. cell ; Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If not, determine whether it is T. min -T cell If ≥a, reduce the tube diameter to D-ΔD3 and continue monitoring the cell temperature T. cell ; Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If not, determine whether it is T. min -T cell ≥a, if not, reduce the tube diameter to D-ΔD4, and continue monitoring the cell temperature T. cell ; Determine if T cell ≤T max If so, determine if it is T. cell ≥T min If so, the inlet of the cold plate is closed by the flow control valve, and the diameter D=0; The mathematical model for the first relationship is f(a) = ΔD; Where a is the temperature change of the battery cell, and ΔD is the change in the diameter of the water pipe; The first relationship mathematical model is based on the cell temperature T. cell The relationship between refrigerant flow rate q and f(T) cell The value of q is obtained from 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 time; Where p is pressure, μ is the dynamic viscosity of the refrigerant, and g is the acceleration due to gravity. , where c p is the specific heat capacity at constant pressure of the refrigerant, k is the thermal conductivity of the refrigerant, and Q is the heat source term per unit volume. Indicates the temperature of the refrigerant; q=h(T) 冷板 -T 冷媒 ), Where q is the heat flux density, h is the convective heat transfer coefficient, and T is the heat transfer temperature. 冷板 It is the surface temperature of the cooling plate, T 冷媒 Where m is the temperature of the refrigerant, and m is the mass flow rate. It is the normal velocity of the refrigerant at the boundary; The heat transfer process between the battery cell and the water-cooled plate: , where q 传导 It is the thermal conductivity of a unit area per unit time, where k is the thermal conductivity of the material, and A is the heat transfer area. It is a temperature gradient; Heat is transferred through convection between the battery cell and the cold plate: ,in, It is the heat transfer rate per unit time, h is the convective heat transfer coefficient, A is the heat transfer area, and T is the heat transfer rate per unit time. 芯 It is the temperature of the cell surface, T 冷媒 It is the temperature of the cooling medium; The relationship between heat and temperature change is expressed as: Where Q is the heat absorbed or released, m is the mass of the object, c is the specific heat capacity, and a is the temperature change. The second relationship mathematical model is k = ΔD / x; Where x is the unit change in the opening of the flow control valve, k is the adjustment degree of the flow control valve, and ΔD is the change in the diameter of the water pipe.

4. An electronic device, characterized in that, include: The device includes a processor, a storage medium, and a bus. 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 perform the power battery temperature control method as described in claim 2.

5. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which is executed by a processor to perform the power battery temperature control method as described in claim 2.

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