Cooling control method and device of power battery, vehicle and storage medium

Abstract

The invention relates to the technical field of vehicle thermal management control, and discloses a cooling control method and device for a power battery, a vehicle and a storage medium, and the method comprises the steps: obtaining cooling liquid parameter information in response to a charging instruction of the power battery; the temperature rise speed of the power battery is calculated according to the parameter information of the cooling liquid, the parameter information of the power battery and the heat exchange speed; determining a cooling strategy of the power battery according to the temperature rise speed and a preset charging demand; wherein the preset charging demand is characterized by different proportions of high charging rates. According to the technical scheme, the problems that the service life is shortened and thermal runaway is caused due to the fact that the power battery is possibly overheated when the vehicle is rapidly charged at high temperature are solved, and the safety of the power battery is improved.

Description

Technical Field

[0001] The present application relates to the technical field of vehicle thermal management control, and particularly relates to a cooling control method, device, vehicle and computer-readable storage medium for a power battery. Background Art

[0002] At present, the power batteries of electric vehicles are mainly lithium-ion batteries. In order to achieve fast charging of the power battery, fast charging is an essential function for the vast majority of electric vehicles. During the fast charging process of the power battery, due to the large charging current, the battery temperature will rise. To ensure the safety of the power battery, the charging current / current ratio of the charging strategy will be limited after reaching a certain SOC (State of Charge). In order to accommodate different users and shorten the charging time of the power battery, it is necessary to increase the proportion of the charging ratio.

[0003] However, a high ratio of the charging ratio may cause the problem of overheating of the power battery, resulting in a reduction in the life of the power battery of the electric vehicle and even potential safety hazards such as thermal runaway. Summary of the Invention

[0004] In view of the above problems, the present application provides a cooling control method, device, vehicle and computer-readable storage medium for a power battery, which solves the problems that the power battery may overheat during high-temperature fast charging, resulting in reduced life and thermal runaway, and improves the safety of the power battery.

[0005] According to one aspect of the embodiments of the present application, a cooling control method for a power battery is provided. The method includes:

[0006] Respond to the charging instruction of the power battery and obtain coolant parameter information;

[0007] Calculate the temperature rise rate of the power battery according to the parameter information of the coolant, the parameter information of the power battery, and the heat exchange speed;

[0008] Determine the cooling strategy of the power battery according to the temperature rise rate and the preset charging requirement; wherein, the preset charging requirement is characterized by different high charging ratio proportions.

[0009] In an optional exemplary embodiment, the preset charging requirement includes charging the power battery based on a first high charging ratio proportion and a second high charging ratio proportion; the method further includes:

[0010] Obtain the corresponding coolant parameter information based on the first high charging ratio proportion in the preset charging requirement;

[0011] Or, obtain the corresponding coolant parameter information based on the second high charging ratio proportion in the preset charging requirement;

[0012] Wherein, the proportion of the first high charging rate is greater than the proportion of the second high charging rate.

[0013] In an optional exemplary embodiment, the method further includes:

[0014] When the preset charging demand is the proportion of the first high charging rate, obtaining the coolant parameter information corresponding to the proportion of the first high charging rate based on a preset coolant parameter map table;

[0015] Or, when the preset charging demand is the proportion of the second high charging rate, obtaining the coolant parameter information corresponding to the proportion of the second high charging rate based on a preset coolant parameter map table;

[0016] Wherein, the preset coolant parameter map table represents the mapping relationship between coolant temperature and coolant flow rate.

[0017] In an optional exemplary embodiment, the coolant parameter information corresponding to the proportion of the first high charging rate includes a first coolant temperature and a first coolant flow rate;

[0018] The coolant parameter information corresponding to the proportion of the second high charging rate includes a second coolant temperature and a second coolant flow rate;

[0019] Wherein, the first coolant temperature is less than the second coolant temperature, and the first coolant flow rate is greater than the second coolant flow rate.

[0020] In an optional exemplary embodiment, the parameter information of the power battery includes the specific heat capacity of the battery cell, the mass of the battery cell, the number of single battery cells, the internal resistance of a single battery cell, and the charging current; the method further includes:

[0021] Determining the internal resistance heat of the battery cell for the preset charging duration of the power battery according to the number of single battery cells, the internal resistance of a single battery cell, and the charging current of the power battery; wherein, the internal resistance of a single battery cell of the power battery is obtained from a calibrated internal resistance map table of the battery cell, and the charging current of the power battery is obtained from a calibrated charging current map table;

[0022] Determining the heat reduction value of the power battery during charging according to the specific heat capacity of the coolant, the density of the coolant, the coolant flow rate, and the preset duration;

[0023] Obtaining the temperature rise rate of the battery cell of the power battery according to the internal resistance heat, the heat reduction value, and the heat exchange rate.

[0024] In an optional exemplary embodiment, the method further includes:

[0025] Determine the heat exchange rate of the power battery during charging according to the heat exchange rate map table of the power battery;

[0026] Determine the heat generation rate according to the internal resistance heat of the battery cell, as well as the specific heat capacity, mass and number of single battery cells of the power battery;

[0027] Determine the heat reduction rate according to the heat reduction value, as well as the specific heat capacity, mass and number of single battery cells of the power battery;

[0028] Calculate the temperature rise rate of the battery cells of the power battery based on the heat generation rate, the heat reduction rate and the heat exchange rate.

[0029] In an optional exemplary embodiment, the method further includes:

[0030] If the temperature rise rate is greater than zero, obtain the corresponding coolant temperature and coolant flow rate in the coolant parameter information according to the preset charging requirement to cool the power battery;

[0031] If the temperature rise rate is less than or equal to zero, control the power battery to stop cooling.

[0032] According to another aspect of the embodiments of the present application, there is provided a cooling control device for a power battery, the device includes:

[0033] An acquisition module, configured to acquire coolant parameter information in response to a charging instruction of the power battery;

[0034] A calculation module, configured to calculate the temperature rise rate of the power battery according to the parameter information of the coolant, as well as the parameter information and heat exchange rate of the power battery;

[0035] A determination module, configured to determine a cooling strategy for the power battery according to the temperature rise rate and a preset charging requirement; wherein, the preset charging requirement is characterized by different proportions of high charging rates.

[0036] According to another aspect of the embodiments of the present application, there is provided a vehicle, including:

[0037] A controller;

[0038] A memory, configured to store one or more programs, and when the one or more programs are executed by the controller, enable the controller to implement the cooling control method of the power battery as described above.

[0039] According to another aspect of the embodiments of the present application, there is provided a computer-readable storage medium storing a computer program, the computer program including at least one executable instruction, and when the executable instruction runs on a cooling control device / vehicle of a power battery, the cooling control device / vehicle of the power battery is caused to perform the operations of the cooling control method of the power battery as described above.

[0040] In the embodiments of the present application, when the vehicle responds to a charging instruction of the power battery and charges the power battery, due to different temperature rise rates of the power battery under different preset charging requirements at high charging rates, the temperature rise speed of the power battery is first calculated according to the parameter information of the coolant, the parameter information of the power battery, and the heat exchange speed. Then, in combination with the temperature rise speed of the power battery and the preset charging requirements based on different high charging rates, a cooling strategy for the power battery is determined. Through the present application, different cooling strategies are executed under different preset charging requirements at high charging rates, solving the problems that the power battery of the vehicle may be overheated during high-temperature fast charging, resulting in reduced battery life, thermal runaway, etc., and improving the safety of the power battery of the vehicle.

[0041] The above description is only an overview of the technical solutions of the embodiments of the present application. In order to be able to understand the technical means of the embodiments of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of the embodiments of the present application more obvious and understandable, the specific embodiments of the present application are hereinafter specifically exemplified. Description of the Drawings

[0042] The drawings are only used to illustrate the embodiments and are not considered as a limitation to the present application. And throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0043] Figure 1 shows a schematic structural diagram of an electric vehicle charging system applicable to the present application;

[0044] Figure 2 shows a schematic flowchart of an embodiment of the cooling control method for a power battery provided by the present application;

[0045] Figure 3 shows a schematic flowchart of an embodiment of obtaining the temperature rise speed of a power battery in the cooling control method for a power battery provided by the present application;

[0046] Figure 4 shows a schematic structural diagram of an embodiment of the cooling control device for a power battery provided by the present application;

[0047] Figure 5 shows a schematic structural diagram of an embodiment of the vehicle provided by the present application. Detailed implementation manners

[0048] Here, exemplary embodiments will be described in detail, and examples thereof are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with the present application. On the contrary, they are merely examples of apparatuses and methods consistent with some aspects of the present application as detailed in the appended claims.

[0049] The block diagrams shown in the drawings are only functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software form, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and / or processor devices and / or microcontroller devices.

[0050] The flowcharts shown in the drawings are only exemplary descriptions and do not necessarily include all contents and operations / steps, nor do they necessarily need to be executed in the described order. For example, some operations / steps can be decomposed, while some operations / steps can be combined or partially combined. Therefore, the actual execution order may change according to the actual situation.

[0051] In the present application, "a plurality of" means two or more. "And / or" describes the association relationship of associated objects and indicates that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after.

[0052] Before introducing the embodiments of the present application, relevant terms involved in the present application will be introduced and described first.

[0053] (1) Charge rate, which is a measure of the charging speed, refers to the current value required for a power battery to be charged to its rated capacity within a specified time. The charge rate is numerically equal to the multiple of the rated capacity of the power battery, that is, charge rate = charging current / rated capacity, and is usually represented by the letter C. Exemplarily, if the rated capacity of a power battery is 100 ampere hours (Ah), when the charging current is 5 amperes (A), the charge rate is 0.05C; when the charging current is 20A, the charge rate is 0.2C; when the charging current is 100A, the charge rate is 1C.

[0054] (2) Map refers to the simulated power point, that is, the voltage and current values at which the power battery can provide the maximum output power, which is one of the important parameters for the power management and power supply design of the power battery. Through the Map value, users can understand the optimal operating range of the power battery, avoid overloading or underloading of the power battery, and thus extend the service life of the power battery.

[0055] (3) SOC is a physical quantity used to reflect the remaining capacity of the battery. The value is defined as the ratio of the remaining capacity of the battery to the battery capacity, that is, SOC = remaining capacity of the battery / battery capacity. Exemplarily, the value range of SOC is 0 to 1 (or 0% to 100%). Among them, when SOC = 0, it means that the battery is completely discharged, that is, the remaining capacity of the battery is 0. When SOC = 1, it means that the battery is fully charged, that is, the remaining capacity of the battery is the same as the battery capacity.

[0056] (4) A lithium-ion battery, also known as a lithium battery, is a secondary battery. Usually, lithium compounds such as lithium cobalt oxide, lithium nickel oxide, or lithium manganese oxide are used as the positive electrode material of the battery, and carbon materials such as petroleum coke or graphite are used as the negative electrode material of the battery. The lithium battery mainly works by the insertion and extraction of lithium ions (Li+) between the positive electrode and the negative electrode. Exemplarily, during the charging process, lithium ions are extracted from the positive electrode of the battery and enter the electrolyte, and the lithium ions in the electrolyte are inserted into the negative electrode. During the discharging process, the lithium ions inserted into the negative electrode are extracted from the negative electrode and enter the electrolyte, and the lithium ions in the electrolyte are inserted into the positive electrode of the battery again.

[0057] Furthermore, based on the above nouns and related term explanations, the design concept of the embodiments of the present application is briefly introduced below:

[0058] Currently, the users of electric vehicles may be non-operating users such as household users, or may be operating users such as online car-hailing and taxis. Due to the range anxiety and consideration of charging efficiency during the use of electric vehicles, the charging efficiency is getting faster and faster to meet the needs of users. In the actual use process, the range anxiety of non-operating users and operating users will be different, which will lead to different starting SOCs when different users charge the electric vehicle. For example, the starting SOC of a non-operating user charging an electric vehicle may be 30%, while the starting SOC of an operating user charging an electric vehicle may be 50%. That is, the starting SOC of the operating user for charging is higher than that of the non-operating user, showing stronger charging anxiety.

[0059] During the fast charging process of an electric vehicle, due to the large charging current, the temperature of the power battery will rise. To ensure the safety of the power battery, the charging current / rate of the charging strategy will be limited after reaching a certain charging SOC. To shorten the charging time, it is necessary to increase the proportion of high charging rates. The lower the starting charging SOC, the smaller the proportion of high charging rates, and vice versa, the larger the proportion of high charging rates. For operation-oriented electric vehicles, due to the high starting charging SOC, the proportion of high charging rates is larger. If operation-oriented electric vehicles with an even higher proportion of high rates adopt a battery thermal management strategy with a smaller proportion of high rates for non-operation-oriented vehicles, it may cause the problem of overheating of the power battery of the electric vehicle, reducing the service life of the power battery of the electric vehicle and even resulting in thermal runaway.

[0060] In view of this, to avoid problems such as reduced life and thermal runaway caused by overheating during battery charging, the present application proposes a cooling control method for a power battery, which specifically includes: responding to a charging instruction of the power battery, obtaining corresponding coolant parameter information based on a preset charging demand; then, calculating the temperature rise rate of the power battery according to the parameter information of the coolant, the parameter information of the power battery, and the heat exchange speed; finally, determining a cooling strategy for the power battery according to the temperature rise rate and the preset charging demand. Among them, the preset charging demand is characterized by different proportions of high charging rates, so that different cooling strategies are executed under different preset charging demands of high charging rates, solving the problems that the power battery of the vehicle may overheat during high-temperature fast charging, resulting in reduced life, thermal runaway, etc., and improving the safety of the power battery of the vehicle.

[0061] In particular, the preferred embodiments of the present application are described below in conjunction with the accompanying drawings of the specification. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application and are not used to limit the present application. And without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0062] Please refer to Figure 1 As shown, it is a schematic diagram of the architecture of an electric vehicle charging system applicable to the embodiments of the present application. The electric vehicle charging system may include a vehicle 11 and a charging device 12. The vehicle 11 and the charging device 12 are electrically connected during the charging process to ensure that the power battery of the vehicle 11 can be charged smoothly. The specific connection method between the vehicle 11 and the charging device 12 in the embodiments of the present application is not limited.

[0063] The embodiments of the present application do not limit the number of devices involved in the above system architecture. For example, there may be more charging devices 12, or other devices may also be included, such as Figure 1 As shown, only the vehicle 11 and the charging device 12 are taken as examples for description. The above devices are briefly introduced below.

[0064] As Figure 1As shown in the figure, the vehicle 11 may include a power battery 111, a battery management system (BMS) 112, and a thermal management system (TMS) 113. Information interaction can be carried out between any two of the battery management system 112, the thermal management system 113, and the charging device 12 through a communication network. Among them, the communication methods adopted by the communication network may include: wireless communication methods and wired communication methods.

[0065] Exemplarily, the charging device 12 can access the network through cellular mobile communication technology and communicate with the battery management system 112 and the thermal management system 113. Among them, the cellular mobile communication technology, for example, includes the 5th generation (5G) mobile communication technology or the next-generation mobile communication technology. Optionally, the charging device 12 can also access the network through short-range wireless communication methods and communicate with the battery management system 112 and the thermal management system 113. Among them, the short-range wireless communication methods, for example, include wireless fidelity (Wi-Fi) technology.

[0066] In an optional implementation manner, the user can send a demand current instruction to the charging device 12 through the battery management system 112. In this way, the charging device 12 can input a charging current to the power battery 111 and the thermal management system 113 according to the demand current instruction output by the battery management system 112 and in combination with the current supply capacity of the charging device 12 itself. The battery management system 112 can also judge the current state of the power battery 111 according to the detected voltage, current, and temperature of the power battery 111 and request corresponding thermal management. After receiving the thermal management request output by the battery management system 112, the thermal management system 113 can perform heating, cooling, or temperature equalization processing on the power battery 111. Exemplarily, the thermal management system 113 can affect the temperature of the power battery 111 by adjusting the coolant temperature and coolant flow rate, thereby controlling the sustainable charging current magnitude and charging safety of the power battery 111.

[0067] It should be noted that the power battery 111 can directly or indirectly provide power for the vehicle 11 and is a general term for rechargeable chemical energy storage appliances such as lead-acid batteries, nickel-cadmium batteries, nickel-metal hydride batteries, lithium batteries, and supercapacitors. In particular, the power battery 111 may include a single electrochemical battery unit, may also include multiple electrochemical battery units, and may also include a battery pack, etc. This application does not make specific limitations on this either.

[0068] The charging device 12 can be a charger, a charging pile, an in-vehicle charger, etc. For example, Figure 1The charging device 12 therein is a charging pile. The embodiments of the present application do not make specific limitations in this regard.

[0069] Next, in combination with the above system architecture and with reference to the accompanying drawings, the cooling control method for a power battery provided by an exemplary embodiment of the present application will be described. It should be noted that the above system architecture is only shown for the convenience of understanding the spirit and principle of the present application, and the embodiments of the present application are not limited in this regard.

[0070] Please continue to refer to Figure 2 As shown, it is a schematic flowchart of a cooling control method for a power battery provided by an embodiment of the present application. Among them, the execution subject of the cooling control method for the power battery can be a terminal device, a server, or other processing devices. The terminal device can be a user equipment (UE), a computer, a mobile device, a user terminal, a terminal, a cellular phone, a personal digital assistant (PDA), a handheld device, a computing device, a vehicle-mounted device, a wearable device, etc. The execution subject of the cooling control method for the power battery can also be an automobile. In some possible implementation manners, the cooling control method for the power battery can be implemented by a processor calling computer-readable instructions stored in a memory. In the following introduction process, for the convenience of description and understanding, the cooling control method for the power battery is applied to a Figure 1 As shown in the battery management system for illustration. As Figure 2 shown, the specific implementation process of this method is as follows:

[0071] Step S200, in response to the charging instruction of the power battery, obtain coolant parameter information.

[0072] Among them, the power battery refers to a power source that provides power for new energy vehicles such as pure electric vehicles, hybrid vehicles, and range-extended vehicles. The power battery is a core component of new energy vehicles, and generally has a capacity of 20 kWh, 40 kWh, 60 kWh, 80 kWh, etc. The charging instruction refers to an instruction to charge the power battery of the vehicle. For example, when the vehicle is already connected to the charging gun, the charging instruction can be a preset time charging start instruction, a remote charging instruction, a vehicle-mounted charging instruction, a charging pile control terminal charging instruction, etc., which is determined according to the actual usage situation, and this embodiment does not make specific limitations.

[0073] Step S300, according to the parameter information of the coolant, as well as the parameter information and heat exchange speed of the power battery, calculate the temperature rise speed of the power battery;

[0074] Among them, the heat exchange speed refers to the heat exchange between the power battery itself and the environment. To ensure the efficiency of the vehicle during charging, the power battery is heated simultaneously. For power batteries of different capacities, the heat exchange amount between the power battery and the environment during charging is different, which will cause power loss during the vehicle charging process. For power batteries with a smaller capacity, due to the smaller area, the heat exchange amount with the environment is correspondingly less; for power batteries with a larger capacity, due to the larger area, the heat exchange amount with the environment is correspondingly more.

[0075] In an optional embodiment, step S300 at least includes steps 310 to 330. Please refer to Figure 3 As shown, the parameter information of the power battery includes the specific heat capacity of the battery cell, the mass of the battery cell, the number of single battery cells, the internal resistance of a single battery cell, and the charging current; the method further includes:

[0076] Step S310, determining the internal resistance heat of the battery cell during the preset charging duration of the power battery according to the number of single battery cells, the internal resistance of a single battery cell, and the charging current of the power battery.

[0077] Among them, the internal resistance of a single battery cell of the power battery is obtained from the calibrated internal resistance map of the battery cell. Please refer to the following

[0078] Calibrated internal resistance map of the battery cell in Table 1 (i, j, a, b are natural numbers).

[0079]

[0080] Table 1

[0081] The charging current of the power battery is obtained from the calibrated charging current map. Please refer to the calibrated charging current map in Table 2 below (i, j, a, b are natural numbers).

[0082]

[0083] Table 2

[0084] It should be noted that the number of single battery cells of the power battery in this embodiment is the basic parameter information of the power battery and can be directly obtained by the vehicle. It should be understood that the number of single battery cells of the power battery is fixed when the vehicle leaves the factory.

[0085] Exemplarily, during the charging process of the power battery of the vehicle, the internal resistance heat of the battery cell of the power battery can be calculated according to the following formula (1).

[0086] Formula (1): T 内 =I 2 *n*R*t.

[0087] Among them, in formula (1), T 内Q is the internal resistance heat of the battery cell during the charging process of the power battery, I is the charging current of the power battery, n is the number of single battery cells of the power battery, R is the internal resistance of a single battery cell of the power battery, and t is the preset charging duration of the vehicle.

[0088] Step S320: Determine the heat reduction value of the power battery during the charging process according to the specific heat capacity of the coolant, the density of the coolant, the coolant flow rate, and the preset duration.

[0089] In this embodiment, during the charging process of the power battery of the vehicle, the heat reduction value of the power battery can be calculated according to the following formula (2).

[0090] Formula (2): T 减 = C W *ρ*V1*t.

[0091] Wherein, in formula (2), T 减 is the heat reduction value of the power battery during the charging process, C W is the specific heat capacity of the coolant, t is the preset charging duration of the vehicle, ρ is the density of the coolant, and V1 is the coolant flow rate of the coolant.

[0092] Step S330: Obtain the temperature rise rate of the battery cell of the power battery according to the internal resistance heat of the battery cell, the heat reduction value, and the heat exchange rate.

[0093] In this embodiment, during the charging process of the power battery, after obtaining the internal resistance heat of the battery cell of the power battery and the heat reduction value of the power battery (i.e., the heat taken away by the coolant to cool the power battery), the temperature rise rate of the power battery can be calculated in combination with the heat exchange rate between the power battery and the environment during the charging process of the power battery, so as to facilitate subsequent determination of the cooling strategy of the power battery in combination with the temperature rise rate and the preset charging requirements, and realize real-time regulation of the cooling strategy during the charging process of the power battery.

[0094] For the above embodiment, the heat exchange rate of the power battery during the charging process can be determined according to the heat exchange rate map table of the power battery;

[0095] Among them, the heat exchange rate of the power battery is determined by the calibrated heat exchange rate map table, and the calibrated heat exchange rate map table in Table 3 below can be referred to (i, j, a, b are natural numbers).

[0096]

[0097] Table 3

[0098] Determine the heat generation rate according to the internal resistance heat of the battery cell, and the specific heat capacity of the battery cell, the mass of the battery cell, and the number of single battery cells of the power battery.

[0099] Determine the heat reduction rate based on the heat reduction value, the specific heat capacity of the battery cell of the power battery, the mass of the battery cell, and the number of single battery cells.

[0100] Calculate the temperature rise rate of the battery cell of the power battery based on the heat generation rate, the heat reduction rate, and the heat exchange rate.

[0101] In this embodiment, during the charging process of the power battery of the vehicle, the law of conservation of energy is observed and satisfies the following formula (3):

[0102] C b *m*Δt*n = T 内 -T 减 +V*t.

[0103] Wherein, in formula (3), C b is the specific heat capacity of the battery cell of the power battery, m is the mass of a single battery cell of the power battery, Δt is the change value of the battery cell temperature during the charging process of the power battery, n is the number of single battery cells of the power battery, T 内 is the heat generated by the internal resistance of the battery cell during the charging process of the power battery, T 减 is the heat reduction value during the charging process of the power battery, V is the heat exchange rate during the charging process of the power battery, and t is the preset charging duration of the vehicle.

[0104] Convert formula (3) to obtain formula (4):

[0105]

[0106] Wherein, in formula (4), K is the temperature rise rate of the battery cell during the charging process of the power battery, is the heat generation rate during the charging process of the power battery, is the heat reduction rate during the charging process of the power battery, is the heat exchange rate during the charging process of the power battery.

[0107] Step S400, determine the cooling strategy of the power battery according to the temperature rise rate and the preset charging requirement.

[0108] Among them, the preset charging demand is characterized by different proportions of high charging rates during the charging process of the power battery. For example, the entire charging process is set to 1, that is, the sum of the proportions of high charging rates and low charging rates is 1. When the power battery is charged from an initial SOC of 30% to an SOC of 90%, the preset charging demand can be that the proportion of the high charging rate is 50%, that is, the proportion of charging at a high charging rate during this charging process is 50%; when the power battery is charged from an initial SOC of 40% to an SOC of 90%, the preset charging demand can be that the proportion of the high charging rate is 60%, that is, the proportion of charging at a high charging rate during this charging process is 60%. In this embodiment, the power battery can be charged according to the preset charging demand with different proportions of high charging rates during the preset charging process.

[0109] It should be noted that during the charging process of the vehicle's power battery, compared with general charging rates of 1C, 2C, 3C, etc., the high charging rate can be but is not limited to charging rates of 4C, 5C, 7C, 10C, etc., which is determined according to the actual application scenario and is not specifically limited here.

[0110] Under different preset charging demands, due to different charging currents, charging rates, battery temperatures, etc. during the charging process of the power battery, there are corresponding coolant parameter information corresponding to the preset charging demands, so as to determine the actual temperature situation of the battery during the charging process according to the coolant parameter information.

[0111] In an alternative embodiment, obtaining the corresponding coolant parameter information based on the preset charging demand includes: obtaining the corresponding coolant parameter information based on the first high charging rate proportion or the second high charging rate proportion in the preset charging demand; wherein, the preset charging demand includes charging the power battery based on the first high charging rate proportion and the second high charging rate proportion, and the first high charging rate proportion is greater than the second high charging rate proportion.

[0112] Exemplarily, in combination with the above embodiments, due to range anxiety and consideration of charging efficiency during the use of electric vehicles, the first high charging rate proportion can make the charging efficiency higher during the entire charging process, and can correspond to users with more range anxiety in the operation nature, and the second high charging rate proportion has a lower charging efficiency compared to the first high charging rate proportion, and can correspond to non-operating nature users.

[0113] In an alternative embodiment, if the user is a user with an operating nature, that is, when the preset charging demand is to charge the vehicle's power battery based on the first high charging rate proportion, the corresponding coolant parameter information corresponding to the first high charging rate proportion can be obtained based on the preset coolant parameter map table, so as to facilitate determining the actual temperature situation of the power battery during the charging process according to the coolant parameter information corresponding to the first high charging rate proportion.

[0114] Further, the coolant parameter information corresponding to the first high charging rate ratio includes the first coolant temperature and the first coolant flow rate. Since the first high charging rate ratio accounts for a higher proportion during the entire charging process, in order to ensure the safety of the power battery, a combination with higher coolant cooling capacity can be selected based on a preset coolant parameter map. For example, a combination with a faster coolant flow rate and a lower coolant temperature can be selected. Specifically, the first coolant temperature and the first coolant flow rate corresponding to the first high charging rate ratio can be obtained with reference to Table 1 below.

[0115] Exemplarily, for a preset charging requirement to charge the power battery of a vehicle based on the first high charging rate ratio, the starting charging SOC of the power battery is relatively high, assumed to be 50%. The corresponding charging current is 100A. That is, when the SOC of the power battery is less than or equal to 50%, the charging current is 100A or close to 100A. When the SOC of the power battery is greater than 50%, considering the temperature rise rate of the power battery, the safety of the battery cells, or being close to the target SOC and the possible need for the user to drive immediately, it is necessary to lower the temperature of the power battery. Therefore, the cooling of the power battery can be increased, and a combination of the minimum coolant temperature and the maximum coolant flow rate can be selected. Through stronger cooling capacity, it is ensured that the battery will not have the problem of over-temperature during charging.

[0116] In an alternative embodiment, if the user is a non-operating user, that is, for a preset charging requirement to charge the power battery of a vehicle based on the second high charging rate ratio, the coolant parameter information corresponding to the second high charging rate ratio can be obtained based on a preset coolant parameter map, so as to facilitate determining the actual temperature situation of the power battery during charging according to the coolant parameter information corresponding to the second high charging rate ratio.

[0117] Further, the coolant parameter information corresponding to the second high charging rate ratio includes the second coolant temperature and the second coolant flow rate. Since the second high charging rate ratio is lower than the first high charging rate ratio during the entire charging process, the second coolant temperature is greater than the first coolant temperature, and the second coolant flow rate is less than the second coolant flow rate. During the charging process of the power battery, in order to balance the safety and charging efficiency of the power battery, a combination with relatively weak coolant cooling capacity can be selected based on a preset coolant parameter map. For example, a combination with a slower coolant flow rate and a higher coolant temperature can be selected. Specifically, the second coolant temperature and the second coolant flow rate corresponding to the second high charging rate ratio can be obtained with reference to Table 1 below.

[0118] Exemplarily, when the preset charging requirement is to charge the power battery of the vehicle based on the proportion of the second highest charging rate, the starting charging SOC of the power battery is relatively low, assumed to be 30%. The corresponding charging current is 100A. That is, when the SOC of the power battery is less than or equal to 30%, the charging current is 100A or close to 100A. When the SOC of the power battery is greater than 30%, considering the temperature rise rate of the power battery, the safety of the battery cells or the large distance from the target SOC, the charging current will continue to decrease. For example, when the SOC of the power battery is 40%, the charging current is 75A; when the SOC of the power battery is 50%, the charging current is 50A; when the SOC of the power battery is 60%, the charging current is 40A. At this time, the required cooling capacity is limited, so a general cooling capacity can be selected. Through the conventional cooling capacity, it is ensured that the battery will not have the problem of over-temperature during charging.

[0119] In the above embodiment, the preset coolant parameter map table is shown in Table 4 below. The preset coolant parameter map table represents the mapping relationship between the coolant temperature and the coolant flow rate. In Table 4, Vmax is the maximum coolant flow rate, Twmax is the maximum coolant temperature, and the values of a and b can be selected according to actual applications and are not specifically limited in this embodiment. For example, a can be a positive integer such as 1, 2, 3, 4, 5, etc., and b can be a positive integer such as 1, 2, 3, 4, 5, etc.

[0120]

[0121] Table 4

[0122] In an exemplary embodiment, during the charging process of the power battery, combining the obtained temperature rise rate of the power battery and the preset charging requirement for the power battery, a cooling strategy suitable for the power battery is determined while taking into account the charging efficiency and safety of the power battery. Exemplarily, if the temperature rise rate of the power battery is greater than zero, it means that the temperature of the power battery may cause over-temperature. At this time, it is necessary to cool down the power battery. Then, according to the preset charging requirement, the corresponding coolant temperature and coolant flow rate in the coolant parameter information are obtained to cool the power battery. For example, the first coolant temperature and the first coolant flow rate corresponding to the proportion of the first highest charging rate are obtained to cool the power battery, or the second coolant temperature and the second coolant flow rate corresponding to the proportion of the second highest charging rate are obtained to cool the power battery, so that different cooling strategies are executed under the preset charging requirements of different high charging rates, solving the problems that the power battery of the vehicle may be over-temperature during high-temperature fast charging, resulting in reduced battery life, thermal runaway, etc., and improving the safety of the power battery of the vehicle.

[0123] If the temperature rise rate of the power battery is less than or equal to zero, it means that the power battery is at an appropriate temperature. At this time, there is no need to cool down the power battery, and the control makes the power battery stop cooling and does not execute the cooling strategy.

[0124] Figure 4 The structural schematic diagram of an embodiment of the cooling control device for the power battery of the present application is shown. Please refer to Figure 4 As shown, the cooling control device 500 of the power battery includes: an acquisition module 510, a calculation module 520, and a determination module 530;

[0125] The acquisition module 510 is configured to obtain coolant parameter information in response to the charging instruction of the power battery;

[0126] The calculation module 520 is configured to calculate the temperature rise rate of the power battery according to the parameter information of the coolant, the parameter information of the power battery, and the heat exchange rate;

[0127] The determination module 530 is configured to determine the cooling strategy of the power battery according to the temperature rise rate and the preset charging requirement; wherein, the preset charging requirement is characterized by different proportions of high charging rates.

[0128] It should be noted that the cooling control device 500 for the power battery provided in the above embodiment belongs to the same concept as the cooling control method for the power battery provided in the foregoing embodiment. The specific manners in which each module and unit perform operations have been described in detail in the method embodiment, and will not be elaborated herein.

[0129] Figure 5 The structural schematic diagram of an embodiment of the vehicle of the present application is shown, which shows the structural schematic diagram of the computer system of the vehicle suitable for implementing the embodiment of the present application. The specific implementation of the vehicle in the specific embodiment of the present application is not limited.

[0130] Please refer to Figure 5 As shown, the vehicle includes: a controller; a memory for storing one or more programs, which, when executed by the controller, are used to execute the above-mentioned cooling control method for the power battery.

[0131] Please continue to refer to Figure 5As shown, the computer system 600 of the vehicle includes a Central Processing Unit (CPU) 601, which can perform various appropriate actions and processes according to the program stored in the Read-Only Memory (ROM) 602 or the program loaded from the storage section 608 into the Random Access Memory (RAM) 603, such as executing the methods in the above embodiments. In the RAM 603, various programs and data required for system operation are also stored. The CPU 601, ROM 602, and RAM 603 are connected to each other via a bus 604. An Input / Output (I / O) interface 605 is also connected to the bus 604.

[0132] The following components are connected to the I / O interface 605: an input section 606 including a keyboard, a mouse, etc.; an output section 607 including, for example, a Cathode Ray Tube (CRT), a Liquid Crystal Display (LCD), etc., and a speaker, etc.; a storage section 608 including a hard disk, etc.; and a communication section 609 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to the I / O interface 605 as needed. A removable medium 611, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 610 as needed so that a computer program read from it can be installed into the storage section 608 as needed.

[0133] Specifically, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication section 609, and / or installed from the removable medium 611. When the computer program is executed by the Central Processing Unit (CPU) 601, various functions defined in the system of the present application are executed.

[0134] Another aspect of the present application also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the cooling control method of the power battery as described above is implemented. The computer-readable storage medium can be included in the vehicle described in the above embodiments, or can exist separately and not be assembled into the vehicle.

[0135] On the other hand, the present application also provides a computer program product or a computer program, which includes at least one executable instruction. When the executable instruction runs on the cooling control device of the power battery / vehicle, it causes the cooling control device of the power battery / vehicle to execute the following power battery cooling control method:

[0136] Respond to the charging instruction of the power battery and obtain coolant parameter information;

[0137] Calculate the temperature rise rate of the power battery according to the parameter information of the coolant, the parameter information of the power battery, and the heat exchange speed;

[0138] Determine the cooling strategy of the power battery according to the temperature rise rate and the preset charging requirement; wherein, the preset charging requirement is characterized by different proportions of high charging rates.

[0139] In an optional manner, the preset charging requirement includes charging the power battery based on the first high charging rate proportion and the second high charging rate proportion;

[0140] The executable instruction can specifically also be used to cause the cooling control device of the power battery / vehicle to perform the following operations:

[0141] Obtain the corresponding coolant parameter information based on the first high charging rate proportion in the preset charging requirement;

[0142] Or, obtain the corresponding coolant parameter information based on the second high charging rate proportion in the preset charging requirement;

[0143] Wherein, the first high charging rate proportion is greater than the second high charging rate proportion.

[0144] In an optional manner, the executable instruction can specifically also be used to cause the cooling control device of the power battery / vehicle to perform the following operations:

[0145] In the case where the preset charging requirement is the first high charging rate proportion, obtain the coolant parameter information corresponding to the first high charging rate proportion based on the preset coolant parameter map table; the coolant parameter information corresponding to the first high charging rate proportion includes the first coolant temperature and the first coolant flow rate;

[0146] Or, in the case where the preset charging requirement is the second high charging rate proportion, obtain the coolant parameter information corresponding to the second high charging rate proportion based on the preset coolant parameter map table; the coolant parameter information corresponding to the second high charging rate proportion includes the second coolant temperature and the second coolant flow rate;

[0147] Among them, the preset coolant parameter map represents the mapping relationship between the coolant temperature and the coolant flow rate. The first coolant temperature is less than the second coolant temperature, and the first coolant flow rate is greater than the second coolant flow rate.

[0148] In an alternative manner, the executable instructions may specifically further be used to cause the cooling control device / vehicle of the power battery to perform the following operations:

[0149] Determine the internal resistance heat of the battery cells during the preset charging duration of the power battery according to the number of single battery cells, the internal resistance of a single battery cell, and the charging current of the power battery; wherein, the internal resistance of a single battery cell of the power battery is obtained from the calibrated internal resistance map of the battery cells, and the charging current of the power battery is obtained from the calibrated charging current map.

[0150] Determine the heat reduction value of the power battery during charging according to the specific heat capacity of the coolant, the density of the coolant, the coolant flow rate, and the preset duration.

[0151] Obtain the temperature rise rate of the battery cells of the power battery based on the internal resistance heat, the heat reduction value, and the heat exchange rate.

[0152] In an alternative manner, the executable instructions may specifically further be used to cause the cooling control device / vehicle of the power battery to perform the following operations:

[0153] Determine the heat exchange rate of the power battery during charging according to the heat exchange rate map of the power battery.

[0154] Determine the heat generation rate according to the internal resistance heat, and the specific heat capacity, mass, and number of single battery cells of the battery cells of the power battery.

[0155] Determine the heat reduction rate according to the heat reduction value, and the specific heat capacity, mass, and number of single battery cells of the battery cells of the power battery.

[0156] Calculate the temperature rise rate of the battery cells of the power battery based on the heat generation rate, the heat reduction rate, and the heat exchange rate.

[0157] In an alternative manner, the executable instructions may specifically further be used to cause the cooling control device / vehicle of the power battery to perform the following operations:

[0158] If the temperature rise rate is greater than zero, cool the power battery according to the corresponding coolant temperature and coolant flow rate in the coolant parameter information obtained according to the preset charging requirement.

[0159] If the temperature rise rate is less than or equal to zero, control the power battery to stop cooling.

[0160] In the embodiments of the present application, when the vehicle responds to the charging instruction of the power battery and charges the power battery, due to different preset charging requirements at different high charging rates, different rates of the power battery will result in a large difference in the temperature rise rate of the power battery. Therefore, first, the temperature rise rate of the power battery is calculated based on the parameter information of the coolant, the parameter information of the power battery, and the heat exchange speed. Then, in combination with the temperature rise rate of the power battery and the preset charging requirements based on different high charging rates, a cooling strategy for the power battery is determined. Through the present application, different cooling strategies are executed under different preset charging requirements at different high charging rates, solving the problems that the power battery of the vehicle may be overheated, resulting in reduced lifespan, thermal runaway, etc. during high-temperature fast charging, and improving the safety of the power battery of the vehicle.

[0161] It should be noted that the computer-readable medium shown in the embodiments of the present application can be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of the computer-readable storage medium may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable storage medium can be any tangible medium that contains or stores a program, and this program can be used by or in combination with an instruction execution system, apparatus, or device. In the present application, a computer-readable signal medium can include a data signal propagated in a baseband or as part of a carrier wave, which carries a computer-readable computer program. Such a propagated data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, and this computer-readable medium can send, propagate, or transmit a program for use by or in combination with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium can be transmitted using any appropriate medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0162] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present application. Among them, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the above-mentioned module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order from that marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram or flowchart, as well as the combination of blocks in the block diagram or flowchart, may be implemented by a dedicated hardware-based system that performs the specified functions or operations, or may be implemented by a combination of dedicated hardware and computer instructions.

[0163] The units involved in the embodiments described in the present application can be implemented in software or in hardware, and the described units can also be provided in a processor. Among them, the names of these units do not constitute a limitation to the units themselves in some cases.

[0164] According to one aspect of the embodiments of the present application, a computer system is further provided, including a central processing unit (CPU), which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) or the program loaded from the storage section into the random access memory (RAM), such as performing the methods in the above embodiments. In the RAM, various programs and data required for system operation are also stored. The CPU, ROM, and RAM are connected to each other through a bus. The input / output (I / O) interface is also connected to the bus.

[0165] The following components are connected to the I / O interface: an input part including a keyboard, a mouse, etc.; an output part including a cathode ray tube (CRT), a liquid crystal display (LCD), etc. and a speaker, etc.; a storage part including a hard disk, etc.; and a communication part including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication part performs communication processing via a network such as the Internet. A drive is also connected to the I / O interface as required. A removable medium such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc. is mounted on the drive as required so that a computer program read from it is installed into the storage part as required.

[0166] The above content is only a preferred exemplary embodiment of the present application and is not used to limit the implementation of the present application. Those of ordinary skill in the art can easily make corresponding adaptations or modifications according to the main concept and spirit of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope required by the claims.

[0167] In the practical application of the relevant data collection and processing in this application book, the informed consent or separate consent of the personal information subject should be obtained strictly in accordance with the requirements of relevant national laws and regulations, and subsequent data use and processing behaviors should be carried out within the scope authorized by laws and regulations and the personal information subject.

Claims

1. A cooling control method for a power battery, characterized in that: The method includes: Responding to a charging instruction of the power battery, obtaining coolant parameter information; Calculating the temperature rise rate of the power battery according to the parameter information of the coolant, the parameter information of the power battery, and the heat exchange rate; The cooling strategy of the power battery is determined according to the temperature rise rate and the preset charging demand; wherein the preset charging demand is characterized by different proportions of high charging rates.

2. The cooling control method of the power battery according to claim 1, characterized in that: The preset charging requirement includes charging the power battery based on a first high charging rate ratio and a second high charging rate ratio; the method further includes: Acquiring corresponding coolant parameter information based on the proportion of the first high charging rate in the preset charging requirement; Alternatively, obtaining corresponding coolant parameter information based on the proportion of the second highest charging rate in the preset charging requirement; Among them, the proportion of the first high charging rate is greater than the proportion of the second high charging rate.

3. The cooling control method of the power battery according to claim 2, characterized in that: The method further comprises: When the preset charging requirement is a first high charging rate ratio, obtaining coolant parameter information corresponding to the first high charging rate ratio based on a preset coolant parameter map table; Alternatively, when the preset charging demand is the second highest charging rate ratio, the coolant parameter information corresponding to the second highest charging rate ratio is obtained based on a preset coolant parameter map table; The preset coolant parameter map table represents the mapping relationship between the coolant temperature and the coolant flow rate.

4. The cooling control method of the power battery according to claim 3, characterized in that: The coolant parameter information corresponding to the first high charging rate ratio includes a first coolant temperature and a first coolant flow rate; The coolant parameter information corresponding to the second high charging rate ratio includes a second coolant temperature and a second coolant flow rate; The first coolant temperature is lower than the second coolant temperature, and the first coolant flow rate is higher than the second coolant flow rate.

5. The cooling control method of the power battery according to claim 1, characterized in that: The parameter information of the power battery includes the specific heat capacity of the battery cell, the mass of the battery cell, the number of single batteries, the internal resistance of the single battery cell and the charging current; the method further includes: Determine the internal resistance heat of the power battery for a preset charging time according to the number of single cells, the internal resistance of the single cells and the charging current of the power battery; wherein the internal resistance of the single cell of the power battery is obtained from a calibrated cell internal resistance map table, and the charging current of the power battery is obtained from a calibrated charging current map table; Determining a heat reduction value of the power battery during the charging process according to the coolant specific heat, coolant density, coolant flow rate and preset time of the coolant; The temperature rise rate of the power battery cell is obtained according to the internal resistance heat of the battery cell, the heat reduction value and the heat exchange rate.

6. The cooling control method of the power battery according to claim 5, characterized in that: The method further comprises: Determining the heat exchange rate of the power battery during the charging process according to the heat exchange rate map of the power battery; Determine the heat generation rate according to the internal resistance heat of the battery cell, as well as the battery cell specific heat capacity, battery cell mass and the number of single batteries of the power battery; Determining a heat reduction rate according to the heat reduction value, and the specific heat capacity of the power battery cells, the cell mass, and the number of single cells; The temperature rise rate of the power battery cell is calculated according to the heat generation rate, the heat reduction rate and the heat exchange rate.

7. The cooling control method for a power battery according to any one of claims 1 to 6, characterized in that: The method further comprises: If the temperature rise rate is greater than zero, obtaining the corresponding coolant temperature and coolant flow in the coolant parameter information according to the preset charging demand to cool the power battery; If the temperature rise rate is less than or equal to zero, the power battery is controlled to stop cooling.

8. A cooling control device for a power battery, characterized in that: The device comprises: An acquisition module, used for responding to a charging instruction of the power battery and acquiring coolant parameter information; A calculation module, used to calculate the temperature rise rate of the power battery according to the parameter information of the coolant, the parameter information of the power battery, and the heat exchange rate; A determination module is used to determine the cooling strategy of the power battery according to the temperature rise rate and the preset charging demand; wherein the preset charging demand is characterized by different proportions of high charging rates.

9. A vehicle, characterized in that: include: Controller; A memory for storing one or more programs, which, when executed by the controller, enables the controller to implement the cooling control method for the power battery 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, which includes at least one executable instruction. When the executable instruction is executed on the cooling control device of the power battery / vehicle, the cooling control device of the power battery / vehicle performs the operation of the cooling control method of the power battery as described in any one of claims 1 to 7.

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