Thermal Management Method, Device, System, Vehicle, Storage Medium and Product of a Battery

Abstract

The present application relates to a thermal management method, device, system, vehicle, storage medium and product for a battery. The method includes: obtaining a thermal management temperature boundary value within a full charge state range; wherein, the thermal management temperature boundary value within the full charge state range is determined according to the self-heat generation start temperatures of at least two reference charge states of the battery; the at least two reference charge states include the maximum charge state within the full charge state range; determining a target temperature boundary value according to the current charge state of the battery and the thermal management temperature boundary value within the full charge state range; and performing thermal management on the battery according to the current temperature of the battery and the target temperature boundary value. Using this method can improve the rationality of battery thermal management.

Description

Technical Field

[0001] The present application relates to the field of new energy technologies, and particularly to a thermal management method, device, system, vehicle, storage medium, and product for a battery. Background Art

[0002] With the development of new energy technologies, batteries, as the core part of energy storage and conversion, have a wider and wider range of applications. During the operation of the battery, heat is continuously generated. As the heat increases, the operating temperature of the battery also rises. Excessively high operating temperatures not only accelerate the physical and chemical changes of the internal materials of the battery, shortening the battery life, but also may cause the battery to have a thermal runaway reaction. Therefore, controlling the battery temperature is very important.

[0003] However, in related technologies, the battery temperature control scheme is unreasonable, affecting the battery operating performance. Summary of the Invention

[0004] Based on this, the present application provides a thermal management method, device, system, vehicle, storage medium, and product for a battery, which can improve the rationality of battery thermal management.

[0005] In a first aspect, the present application provides a thermal management method for a battery. The method includes: obtaining a thermal management temperature boundary value within a full charge state range; wherein, the thermal management temperature boundary value within the full charge state range is determined according to the self-heat generation start temperatures of at least two reference charge states of the battery; the at least two reference charge states include the maximum charge state within the full charge state range; determining a target temperature boundary value according to the current charge state of the battery and the thermal management temperature boundary value within the full charge state range; and performing thermal management on the battery according to the current temperature of the battery and the target temperature boundary value.

[0006] In the technical solution of the embodiment of the present application, thermal management of the battery can be flexibly performed according to the current state of charge of the battery, the current temperature, and the thermal management temperature boundary values of the fully charged state range set precisely, so that the thermal management of the battery can match the current operating state of the battery and meet the thermal management requirements corresponding to the thermal management temperature boundary values of the fully charged state range, thereby improving the rationality of battery thermal management; the thermal management temperature boundary values of the fully charged state range are not fixed, but change in height. Then, when the thermal management temperature boundary values of the fully charged state range are relatively high, the allowable operating temperature of the battery is relatively high, avoiding the situation in the related art where a relatively fixed temperature threshold is used for battery thermal management, resulting in the battery always operating at a relatively fixed temperature, thereby improving the charging efficiency of the battery and being beneficial to enhancing the fast charging performance of the battery; moreover, by performing thermal management of the battery according to the thermal management temperature boundary values of the fully charged state range, it is possible to avoid the temperature of the battery exceeding the thermal management temperature boundary value corresponding to the state of charge as much as possible, so that the battery still operates within a safe temperature range, reducing the probability of thermal runaway of the battery, improving the reliability of the battery, and reducing the energy consumption of thermal management; in addition, the thermal management temperature boundary values of the fully charged state range are determined based on the self-heat release start temperatures of at least two reference states of charge, so that the temperature of the battery will not exceed the self-heat release start temperature of the battery as much as possible, improving the safety of battery use, and there is no need to measure the self-heat release start temperatures of all states of charge in the fully charged state range, reducing the establishment time of the thermal management temperature boundary values of the fully charged state range, thereby improving the establishment efficiency of the thermal management temperature boundary values of the fully charged state range.

[0007] In some embodiments, obtaining the thermal management temperature boundary values of the fully charged state range includes: obtaining the self-heat release start temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include the maximum state of charge in the fully charged state range; determining the thermal management temperature boundary values of the fully charged state range according to the self-heat release start temperatures of the at least two reference states of charge. In the technical solution of the embodiment of the present application, determining the thermal management temperature boundary values of the fully charged state range according to the self-heat release start temperatures of at least two reference states of charge, without measuring the self-heat release start temperatures of all states of charge in the fully charged state range, reduces the establishment time of the thermal management temperature boundary values of the fully charged state range, thereby improving the establishment efficiency of the thermal management temperature boundary values of the fully charged state range.

[0008] In some embodiments, determining the thermal management temperature boundary value of the full state of charge range according to the self-heat release start temperature of at least two reference states of charge includes: determining the thermal management temperature boundary value of the state of charge within the range from 0 to the minimum reference state of charge as the self-heat release start temperature of the minimum reference state of charge; determining the self-heat release start temperatures of at least two reference states of charge as the thermal management temperature boundary values of at least two reference states of charge; and determining the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge according to the self-heat release start temperatures of at least two reference states of charge. In the technical solution of the embodiments of the present application, determining the thermal management temperature boundary value of the state of charge within the range from 0 to the minimum reference state of charge as the self-heat release start temperature of the minimum reference state of charge improves the convenience of determining the thermal management temperature boundary value of each state of charge within this range; determining the self-heat release start temperatures of at least two reference states of charge as the thermal management temperature boundary values of at least two reference states of charge can ensure the accuracy of the thermal management temperature boundary values of at least two reference states of charge; and determining the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge according to the self-heat release start temperatures of two adjacent reference states of charge avoids the interference of the self-heat release start temperatures of other reference states of charge outside the two adjacent reference states of charge on the determination of the thermal management temperature boundary value of the state of charge between the two adjacent reference states of charge, thereby improving the accuracy of the determined thermal management temperature boundary value of the state of charge between two adjacent reference states of charge.

[0009] In some embodiments, determining the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge according to the self-heat release start temperatures of two adjacent reference states of charge includes: determining the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge according to the change rate of the self-heat release start temperatures of two adjacent reference states of charge. In the technical solution of the embodiments of the present application, considering the gradual change process of the self-heat release characteristics of the battery at different states of charge makes the determination of the thermal management temperature boundary value more in line with the actual thermal behavior of the battery, thereby improving the accuracy of the determined thermal management temperature boundary value of the state of charge between two adjacent reference states of charge.

[0010] In some embodiments, determining the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge according to the self-heat release start temperature of two adjacent reference states of charge includes: determining the self-heat release start temperature of the larger reference state of charge among two adjacent reference states of charge as the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge. In the technical solution of the embodiments of the present application, by determining the self-heat release start temperature of the larger reference state of charge among two adjacent reference states of charge as the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge, the convenience of determining the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge is improved.

[0011] In some embodiments, obtaining the thermal management temperature boundary value of the full state of charge range includes: obtaining the current health state of the battery; determining, from the obtained mapping relationships of multiple health states, the thermal management temperature boundary value of the full state of charge range that matches the current health state; wherein, the mapping relationship of each health state includes: the corresponding relationship between the full state of charge range and the thermal management temperature boundary value under each health state. In the technical solution of the embodiments of the present application, determining, from the mapping relationships of multiple health states, the thermal management temperature boundary value of the full state of charge range that matches the current health state of the battery, and further, the thermal management performed on the battery can also match the current health state of the battery, avoiding the situation that the health state of the battery decreases after long-term use, but still using the thermal management temperature boundary value of the full state of charge range of a higher health state to perform thermal management on the battery, resulting in the occurrence of the overheat situation of the battery. Therefore, the embodiments of the present application can improve the reliability of the battery.

[0012] In some embodiments, obtaining the thermal management temperature boundary values for the full state-of-charge range includes: obtaining the computing power of the battery management system and / or the attribute information of the battery; determining the mapping type between the state of charge and the thermal management temperature boundary values according to the computing power of the battery management system and / or the attribute information of the battery; and obtaining the thermal management temperature boundary values for the full state-of-charge range according to the mapping type. In the technical solution of the embodiments of the present application, according to the computing power of the battery management system, the mapping type between the state of charge and the thermal management temperature boundary values is determined. Thus, when the computing power of the battery management system is higher, the change in the thermal management temperature boundary values is more refined; when the computing power of the battery management system is lower, the change in the thermal management temperature boundary values is more concise. This enables the battery management system to operate reasonably under different computing powers, improving the rationality of battery thermal management. According to the attribute information of the battery, the mapping type between the state of charge and the thermal management temperature boundary values is determined. Thus, when the attribute information of the battery indicates a higher battery quality, the thermal management temperature boundary value in the low state of charge is higher; when the attribute information of the battery indicates a lower battery quality, the thermal management temperature boundary value in the low state of charge is lower. In this way, fine-grained thermal management based on the actual condition of the battery can improve the stability of battery operation.

[0013] In some embodiments, the target temperature boundary values include a first temperature boundary value and a second temperature boundary value; determining the target temperature boundary values according to the current state of charge of the battery and the thermal management temperature boundary values for the full state-of-charge range includes: determining the thermal management temperature boundary value corresponding to the current state of charge of the battery in the thermal management temperature boundary values for the full state-of-charge range as the first temperature boundary value; determining the difference between the first temperature boundary value and a preset temperature offset value as the second temperature boundary value; and performing thermal management on the battery according to the current temperature of the battery, the first temperature boundary value, and the second temperature boundary value. In the technical solution of the embodiments of the present application, the first temperature boundary value and the second temperature boundary value for each state of charge are determined through the thermal management temperature boundary values for the full state-of-charge range. The second temperature boundary value is the difference between the first temperature boundary value and a preset temperature offset value. In this way, there are a first temperature boundary value and a second temperature boundary value with a difference of the temperature offset value for each state of charge, which is conducive to performing multiple levels of thermal management on the battery according to the current temperature of the battery, the first temperature boundary value, and the second temperature boundary value, improving the effectiveness of thermal battery management.

[0014] In some embodiments, thermal management of the battery is performed based on the current temperature of the battery, the first temperature boundary value, and the second temperature boundary value, including: when the current temperature is greater than or equal to the first temperature boundary value, performing thermal management on the battery in a first thermal management manner; when the current temperature is greater than or equal to the second temperature boundary value and less than the first temperature boundary value, performing thermal management on the battery in a second thermal management manner; wherein, the temperature drop rate of the battery in the first thermal management manner is greater than the temperature drop rate of the battery in the second thermal management manner. In the technical solution of the embodiments of the present application, when the current temperature of the battery is greater than or equal to the first temperature boundary value, it indicates that the probability of thermal runaway risk of the battery is relatively high, and the first thermal management manner with a larger temperature drop rate is adopted, so as to achieve rapid cooling of the battery; when the current temperature of the battery is between the second temperature critical value and the first temperature boundary value, it indicates that the probability of thermal runaway risk of the battery is relatively low, and the second thermal management manner with a smaller temperature drop rate is switched to, so as to achieve gentle cooling of the battery, improve the pertinence of battery thermal management, and further improve the rationality of battery thermal management.

[0015] In some embodiments, thermal management of the battery is performed based on the current temperature of the battery and the target temperature boundary value, including: when the battery is in a charging state, obtaining the charging mode of the battery; when the charging mode of the battery is a slow charging mode, controlling the operation of the heat dissipation device of the battery according to the current temperature of the battery and the target temperature boundary value, and / or reducing the charging rate of the battery; when the charging mode of the battery is a fast charging mode, controlling the operation of the heat dissipation device of the battery according to the current temperature of the battery and the target temperature boundary value. In the technical solution of the embodiments of the present application, when the charging mode of the battery is a slow charging mode, a thermal management solution of reducing the charging rate of the battery can be considered, which is beneficial to reducing the cooling pressure of the heat dissipation device and improving the reliability of the battery during charging; when the charging mode of the battery is a fast charging mode, a thermal management solution considering the operation of the heat dissipation device is adopted to ensure the smooth progress of fast charging as much as possible and improve the charging efficiency of the battery.

[0016] In some embodiments, thermal management of the battery is performed according to the current temperature of the battery and the target temperature boundary value, including: obtaining the target temperature difference between the current temperature of the battery and the target temperature boundary value; determining the target operating power of the heat dissipation device according to the target temperature difference and the corresponding relationship between the operating power of the heat dissipation device of the battery and the temperature difference; and controlling the heat dissipation device to operate at the target operating power. In the technical solution of the embodiment of the present application, the target operating power of the heat dissipation device is determined according to the target temperature difference between the current temperature of the battery and the target temperature boundary value, so that the target operating power of the heat dissipation device can be flexibly determined according to different target temperature differences. For example, when the target temperature difference is large, the target operating power of the heat dissipation device is also large; when the target temperature difference is small, the target operating power of the heat dissipation device is also small. Furthermore, accurate battery thermal management can be achieved, the temperature fluctuation of the battery is reduced, and the reliability of the battery is improved.

[0017] In some embodiments, obtaining the current state of charge and the current temperature of the battery includes: obtaining the state of charge of a plurality of battery cells and the temperatures of the plurality of battery cells; determining the maximum value among the states of charge of the plurality of battery cells as the current state of charge, and determining the maximum value among the temperatures of the plurality of battery cells as the current temperature. In the technical solution of the embodiment of the present application, since the self-heating start temperature decreases as the state of charge increases, the maximum value among the states of charge of the plurality of battery cells is determined as the current state of charge. Thus, the target temperature boundary value matching the current state of charge is the minimum temperature boundary value among the plurality of temperature boundary values matching the states of charge of the plurality of battery cells. Therefore, performing thermal management of the battery according to the minimum temperature boundary value can improve the reliability of all battery cells in the battery; and, determining the maximum value among the temperatures of the plurality of battery cells as the current temperature, so that performing thermal management of the battery according to the maximum value among the temperatures of the plurality of battery cells can improve the reliability of all battery cells in the battery.

[0018] In a second aspect, the present application provides a thermal management device for a battery. The thermal management device for the battery includes: an acquisition module, configured to acquire the thermal management temperature boundary values within the full state of charge range; wherein the thermal management temperature boundary values within the full state of charge range are determined according to the self-heating start temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include the maximum state of charge within the full state of charge range; a determination module, configured to determine the target temperature boundary value according to the current state of charge of the battery and the thermal management temperature boundary values within the full state of charge range; and a thermal management module, configured to perform thermal management of the battery according to the current temperature of the battery and the target temperature boundary value.

[0019] In a third aspect, the present application provides a battery management system, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the steps of the method in any one of the above are implemented.

[0020] Fourth aspect, the present application provides a vehicle, which includes a battery and the above-mentioned battery management system; the battery is connected to the battery management system.

[0021] Fifth aspect, the present application provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the method according to any one of the above are implemented.

[0022] Sixth aspect, the present application provides a computer program product, including a computer program, and when the computer program is executed by a processor, the steps of the method according to any one of the above are implemented. Description of the Drawings

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the drawings required to be used in the description of the embodiments of the present application or related technologies. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0024] Figure 1 Structural schematic diagram of the electrical device provided for some embodiments;

[0025] Figure 2 Flow schematic diagram of the battery thermal management method provided for the first embodiment;

[0026] Figure 3 Flow schematic diagram of the battery thermal management method provided for the second embodiment;

[0027] Figure 4 Flow schematic diagram of the battery thermal management method provided for the third embodiment;

[0028] Figure 5 Flow schematic diagram of the battery thermal management method provided for the fourth embodiment;

[0029] Figure 6 Flow schematic diagram of the battery thermal management method provided for the fifth embodiment;

[0030] Figure 7 Flow schematic diagram of the battery thermal management method provided for the sixth embodiment;

[0031] Figure 8 Flow schematic diagram of the battery thermal management method provided for the seventh embodiment;

[0032] Figure 9 Flow schematic diagram of the battery thermal management method provided for the eighth embodiment;

[0033] Figure 10 Schematic diagram of the thermal management temperature boundary values for the full state of charge range provided for the first embodiment;

[0034] Figure 11 Schematic diagram of the thermal management temperature boundary values for the full state of charge range provided for the second embodiment;

[0035] Figure 12 Schematic diagram of the thermal management temperature boundary values for the full state of charge range provided for the third embodiment:

[0036] Figure 13 Schematic diagram of the structure of the thermal management device for the battery provided for some embodiments;

[0037] Figure 14 Schematic diagram of the structure of the battery management system provided for some embodiments. Detailed implementation manners

[0038] The embodiments of the technical solution of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to illustrate the technical solution of the present application more clearly, so they are only examples and cannot be used to limit the protection scope of the present application.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion.

[0040] In the description of the embodiments of this application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "a plurality" means more than two unless otherwise specifically defined.

[0041] Referring to "embodiments" herein means that the specific features, structures or characteristics described in connection with the embodiments may be included in at least one embodiment of this application. The phrase appears in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0042] In the description of the embodiments of the present application, the term "and / or" is merely an association relationship describing associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after.

[0043] The thermal management of the battery management system (Battery Management System, BMS) of the current vehicle adopts the following solution: Based on a set fixed temperature threshold, when the battery temperature is higher than the fixed temperature threshold, thermal management is performed on the battery. Exemplarily, performing thermal management on the battery may include controlling the start of a water cooling device.

[0044] However, the above-mentioned fixed temperature threshold is often set based on experience. The solution for battery thermal management according to the fixed temperature threshold and the current temperature of the battery will cause the problem of unreasonable battery temperature control. For example, when the fixed temperature threshold is set relatively high, it is easy to cause the working temperature of the battery to be high, affecting the reliability of the battery. Another example is that when the fixed temperature threshold is set relatively low, the battery temperature is low, which will not only reduce the charging ability of the battery, but also requires continuous thermal management of the battery to maintain the low temperature, increasing the power consumption of the battery thermal management.

[0045] To alleviate the above problems, through research, it is found that the safe operating temperature of the battery in a low state of charge (State of Charge, SOC) is different from that in a high state of charge. By setting the thermal management temperature boundary value of the battery in the fully charged state and performing battery thermal management according to the thermal management temperature boundary value of the fully charged state, the battery can work as much as possible below the thermal management temperature boundary value, which can improve the reliability of the battery. And by flexibly performing battery thermal management according to the thermal management temperature boundary value in the fully charged state, the thermal management temperature boundary value of the battery changes dynamically with the change of the state of charge of the battery. Therefore, the situation where the battery always works at a relatively low temperature can be avoided, and the charging ability of the battery can be improved.

[0046] Based on the above considerations, the present application provides a method for thermal management of a battery, obtaining a thermal management temperature boundary value within a fully charged state range; wherein, the thermal management temperature boundary value within the fully charged state range is determined according to the self-heating start temperature of at least two reference states of charge of the battery; at least two reference states of charge include the maximum state of charge within the fully charged state range; determining a target temperature boundary value according to the current state of charge of the battery and the thermal management temperature boundary value within the fully charged state range; and performing thermal management on the battery according to the current temperature of the battery and the target temperature boundary value.

[0047] In this way, the thermal management of the battery can be flexibly carried out according to the current state of charge of the battery, the current temperature, and the thermal management temperature boundary values of the accurately set full charge state range, so that the thermal management of the battery can match the current operating state of the battery and meet the thermal management requirements corresponding to the thermal management temperature boundary values of the full charge state range, thereby improving the rationality of the battery thermal management; the thermal management temperature boundary values of the full charge state range are not fixed, but vary between high and low. Then, when the thermal management temperature boundary values of the full charge state range are relatively high, the allowable operating temperature of the battery is relatively high, avoiding the situation in the related art where a relatively fixed temperature threshold is used for the thermal management of the battery, resulting in the battery always operating at a relatively fixed temperature, thereby improving the charging efficiency of the battery and being beneficial to enhancing the fast charging performance of the battery; moreover, by carrying out the thermal management of the battery according to the thermal management temperature boundary values of the full charge state range, it is possible to avoid the temperature of the battery exceeding the thermal management temperature boundary value corresponding to the state of charge as much as possible, and further enabling the battery to still operate within the safe temperature range, reducing the probability of the battery thermal runaway, improving the reliability of the battery, and reducing the energy consumption of the thermal management; in addition, the thermal management temperature boundary values of the full charge state range are determined according to the self-heat release start temperatures of at least two reference states of charge, so that the temperature of the battery will not exceed the self-heat release start temperature of the battery as much as possible, improving the safety of battery use, and without the need to measure the self-heat release start temperatures of all states of charge in the full charge range, reducing the establishment time of the thermal management temperature boundary values of the full charge state range, thereby improving the establishment efficiency of the thermal management temperature boundary values of the full charge state range.

[0048] The thermal management method of the battery disclosed in the embodiments of the present application can be applied to a battery management system or other control devices (for the convenience of description, the following takes the application to a battery management system as an example), and the battery management system can be included in an electrical device. Exemplarily, the electrical device can include but is not limited to one of the following: vehicles, mobile phones, tablets, laptop computers, electric toys, electric tools, battery cars, electric vehicles, ships, spacecraft, and so on. In some embodiments, the vehicle can be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle, or an extended-range electric vehicle, etc. In some embodiments, the electric toy can include a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy, or an electric aircraft toy, and so on. In some embodiments, the spacecraft can include an airplane, a rocket, a space shuttle, or a spaceship, and so on.

[0049] Figure 1 The structural schematic diagram of the electrical device provided for some embodiments is as Figure 1As shown, a battery 11 is provided inside the electrical device 10. The battery 11 can be arranged at the bottom, head or tail of the electrical device 10. The battery 11 can be used to supply power to the electrical device 10. For example, the battery 11 can serve as the driving power source of the electrical device 10, replacing or partially replacing fuel or natural gas to provide driving power for the electrical device 10. In some embodiments, the battery 11 can not only serve as the driving power source of the electrical device 10, but also serve as the operating power source of the electrical device 10. The electrical device 10 may further include a battery management system 12, and the battery management system 12 is capable of detecting the temperature and state of charge of the battery 11. In some embodiments, the electrical device 10 may further include a heat dissipation device 13. The heat dissipation device 13 is arranged near or around the battery 11. The battery management system 12 can control the activation of the heat dissipation device 13 when the temperature of the battery 11 is higher than the temperature threshold to achieve the cooling of the battery 11.

[0050] Figure 2 The flowchart of the battery thermal management method provided for the first embodiment is applied to the battery management system. The method includes:

[0051] S201. Obtain the thermal management temperature boundary values within the full state of charge range.

[0052] In the embodiments of the present application, the thermal management temperature boundary values within the full state of charge range are different from the temperature thresholds in the related art. The existing temperature thresholds are empirical values, while the embodiments of the present application are fine thermal management temperature boundary values within the full state of charge range, that is, the thermal management temperature boundary values matching the 0% to 100% state of charge range of the battery.

[0053] In some embodiments, the thermal management temperature boundary values within the full state of charge range can be determined according to the characteristics of the battery. For example, in some embodiments, the thermal management temperature boundary values within the full state of charge range can be determined according to the thermal safety temperature boundary values of the battery. For example, the thermal management temperature boundary values within the full state of charge range can be the thermal safety temperature boundary values of the battery to improve the fineness of the thermal management temperature boundary values within the full state of charge range. For another example, the thermal management temperature boundary values within the full state of charge range can be determined according to the thermal safety temperature boundary values of the battery at at least two states of charge to improve the convenience of obtaining the thermal management temperature boundary values within the full state of charge range.

[0054] In some embodiments, the thermal safety temperature boundary value of a battery refers to the maximum temperature at which the battery can operate safely without an external heat source. For example, the maximum temperature at which the battery can operate safely includes the temperature at which the battery does not react when there is no charge or discharge. Exemplarily, the temperature at which the battery does not react may include at least one of the following: the critical temperature at which the electrolyte of the battery decomposes, and the self-heat generation start temperature of the battery. In some embodiments, the thermal safety temperature boundary value of the battery may be the self-heat generation start temperature of the battery. In other embodiments, the thermal safety temperature boundary value of the battery may be the smaller value between the self-heat generation start temperature of the battery and the critical temperature at which the electrolyte decomposes.

[0055] In some embodiments, the thermal management temperature boundary value in the full charge state range is determined based on the self-heat generation start temperature of the battery. Exemplarily, the thermal management temperature boundary value in the full charge state range is determined based on the self-heat generation start temperatures of at least two reference charge states of the battery.

[0056] In another embodiment, the thermal management temperature boundary value in the full charge state range is determined based on the self-heat generation start temperature of the battery and the critical temperature at which the electrolyte of the battery decomposes. Exemplarily, the thermal management temperature boundary value in the full charge state range is determined based on the critical temperature at which the electrolyte decomposes and the self-heat generation start temperatures of at least two reference charge states of the battery.

[0057] In still other embodiments, the thermal management temperature boundary value in the full charge state range is determined based on the self-heat generation start temperature of the battery and the maximum operating temperature of the battery. For example, the maximum operating temperature of the battery is the maximum temperature at which the battery can operate reliably. Exemplarily, the maximum operating temperature of the battery may be included in the attribute information of the battery. Exemplarily, the thermal management temperature boundary value in the full charge state range is determined based on the maximum operating temperature of the battery and the self-heat generation start temperatures of at least two reference charge states of the battery.

[0058] In some embodiments, the obtained thermal management temperature boundary value in the full charge state range may include: the thermal management temperature boundary value in the full charge state range that matches at least one of the current health state, the computing power of the battery management system, and the attribute information of the battery.

[0059] Exemplarily, when the health state of the battery is different, the change situation of the thermal management temperature boundary value in the full charge state range is different. Exemplarily, when the computing power of the battery management system is different, the change situation of the thermal management temperature boundary value in the full charge state range is different. Exemplarily, when the attribute information of the battery is different, the change situation of the thermal management temperature boundary value in the full charge state range is different.

[0060] For example, the thermal management temperature boundary values of the obtained full state of charge range may include: the thermal management temperature boundary values of the full state of charge range that match the current state of health. For example, the thermal management temperature boundary values of the obtained full state of charge range may include: the thermal management temperature boundary values of the full state of charge range that match the computing power of the battery management system. For example, the thermal management temperature boundary values of the obtained full state of charge range may include: the thermal management temperature boundary values of the full state of charge range that match the attribute information of the battery. For example, the thermal management temperature boundary values of the obtained full state of charge range may include: the thermal management temperature boundary values of the full state of charge range that match the current state of health and the computing power of the battery management system.

[0061] In some embodiments, the attribute information of the battery may include at least one of the following: the type of the battery, the cycle life of the battery, the state of health of the battery, the energy density of the battery, the self-discharge rate of the battery, etc.

[0062] In some embodiments, the thermal management temperature boundary values of each state of charge within the full state of charge range are less than or equal to the self-heat release start temperature of each state of charge. In some embodiments, the thermal management temperature boundary values of each state of charge within the full state of charge range show a downward trend as the state of charge increases.

[0063] In some embodiments, the self-heat release start temperature of the battery can be obtained by measuring the self-heat release start temperature of a reference battery. Among them, the reference battery has the same characteristics as the battery.

[0064] In some embodiments, the reference battery can be a test battery. In some embodiments, the reference battery can be a single cell. In some embodiments, the reference battery having the same characteristics as the battery may include: the reference battery having the same characteristics as the cells in the battery. In some embodiments, the reference battery having the same characteristics as the battery may include at least one of the following being the same: the battery attributes are the same, the shape and size are the same, the manufacturer is the same, the production equipment is the same, etc.

[0065] In some embodiments, the self-heat release start temperatures of different states of charge are measured using different reference batteries, so as to avoid the situation where the measurement of the self-heat release start temperature of one state of charge triggers the self-heat release reaction of the reference battery, and continuing to use this reference battery to measure the self-heat release start temperature of the next state of charge results in inaccurate measurement of the self-heat release start temperature of the next measurement.

[0066] Exemplarily, the thermal management temperature boundary values within the full state of charge range can be stored in the form of a mapping table. For example, in the battery management system, multiple state of charge values within the set intervals in the full state of charge range and the thermal management temperature boundary values corresponding to the multiple state of charge values are stored. For example, the set interval can be 0.01, 0.005, 0.02, etc. Additionally, exemplarily, the thermal management temperature boundary values within the full state of charge range can be stored in the form of a curve. Additionally, exemplarily, the thermal management temperature boundary values within the full state of charge range can be stored in the form of a functional relationship.

[0067] In some embodiments, the thermal management temperature boundary values within the full state of charge range are determined based on the self-heat generation start temperatures at at least two reference state of charge values. In some embodiments, the thermal management temperature boundary value for each state of charge within the full state of charge range is the self-heat generation start temperature of the battery at each state of charge within the full state of charge range. In other embodiments, the thermal management temperature boundary value for each state of charge within the full state of charge range is obtained based on the analysis of the self-heat generation start temperatures at at least two reference state of charge values.

[0068] In some embodiments, among at least two reference state of charge values arranged from large to small or from small to large, the intervals between adjacent two state of charge values can be the same or different. Exemplarily, the interval between adjacent two state of charge values can be flexibly determined according to the accuracy requirement of the thermal management temperature boundary values within the full state of charge range and / or the requirement of calculation convenience. For example, in the case of a higher accuracy requirement, the interval between adjacent two state of charge values is smaller; conversely, in the case of a lower accuracy requirement, the interval between adjacent two state of charge values is larger. Another example is that in the case of a higher requirement for calculation convenience, the interval between adjacent two state of charge values is larger; conversely, in the case of a lower requirement for calculation convenience, the interval between adjacent two state of charge values is smaller.

[0069] In some embodiments, the thermal management temperature boundary values within the full state of charge range can be pre-stored in the battery management system. In other embodiments, the thermal management temperature boundary values within the full state of charge range can be obtained by the battery management system from a storage medium or other devices.

[0070] S202. Determine the target temperature boundary value according to the current state of charge of the battery and the thermal management temperature boundary values within the full state of charge range.

[0071] In some embodiments, the battery can include an assembly formed by connecting battery cells in series, parallel, or series-parallel connection. Exemplarily, the battery can be a battery pack, battery module, battery device, battery assembly, or battery cell, etc. In some embodiments, the battery can include multiple battery monomers.

[0072] The state of charge is the ratio of the remaining capacity of the battery to the capacity at full charge state, usually expressed as a percentage. The value range of the state of charge is from 0 (i.e., 0%) to 1 (i.e., 100%). When the state of charge is 0, it means the battery is fully discharged, and when the state of charge is 1, it means the battery is fully charged.

[0073] In some embodiments, the current state of charge and the current temperature of the battery can change in real time. For example, the battery management system continuously obtains the current state of charge and the current temperature of the battery. For example, the battery management system can obtain the current state of charge and the current temperature of the battery every preset time interval.

[0074] In some embodiments, the thermal management temperature boundary value of the current state of charge within the full state of charge range can be determined as the target temperature boundary value.

[0075] In some embodiments, the battery thermal management method can be applied during the charging process of the battery. For example, in response to a charging instruction for charging the battery / vehicle, the current state of charge and the current temperature of the battery can be obtained. In other embodiments, the battery thermal management method can be applied during the discharging process of the battery. For example, in response to a start instruction for starting the vehicle, the current state of charge and the current temperature of the battery can be obtained.

[0076] S203. Perform thermal management on the battery according to the current temperature of the battery and the target temperature boundary value.

[0077] In some embodiments, performing thermal management on the battery can include controlling the battery to cool down. Exemplarily, controlling the battery to cool down can include at least one of the following: controlling the operation of the battery's heat dissipation device, controlling the reduction of the battery's charging rate, and controlling the reduction of the battery's discharging rate. Exemplarily, the heat dissipation device can include a liquid cooling device and / or an air cooling device.

[0078] In some embodiments, the higher the operating power of the heat dissipation device, the higher the heat dissipation efficiency. Exemplarily, taking the heat dissipation device as a liquid cooling device as an example, the higher the operating power of the liquid cooling device, the faster the circulation speed of the liquid in the liquid cooling device. For example, the liquid cooling device can be a water cooling device. Another exemplarily, taking the heat dissipation device as an air cooling device as an example, the higher the operating power of the air cooling device, the faster the fan speed of the air cooling device.

[0079] In some embodiments, thermal management of the battery can also be performed according to the state of the battery, i.e., the charging state or the discharging state. Exemplarily, when the state of the battery is the charging state, thermal management of the battery can include at least one of the following: controlling the operation of the heat dissipation device of the battery, controlling the reduction of the charging rate of the battery. Exemplarily, when the state of the battery is the discharging state, thermal management of the battery can include at least one of the following: controlling the operation of the heat dissipation device of the battery, controlling the reduction of the discharging rate of the battery.

[0080] Exemplarily, thermal management of the battery includes controlling the operation of the heat dissipation device of the battery. Another example is that thermal management of the battery includes controlling the operation of the heat dissipation device of the battery and controlling the reduction of the charging rate of the battery.

[0081] In some embodiments, thermal management of the battery can be performed according to the magnitude relationship between the current temperature and the target temperature boundary value. For example, when the current temperature is greater than or equal to the target temperature boundary value, thermal management of the battery includes controlling the battery to cool down. Another example is that when the current temperature is less than the target temperature boundary value, thermal management of the battery includes not controlling the temperature of the battery.

[0082] In the technical solution of the embodiment of the present application, thermal management of the battery can be flexibly performed according to the current state of charge of the battery, the current temperature, and the thermal management temperature boundary values of the fully charged state range set precisely. As a result, thermal management of the battery can match the current operating state of the battery and meet the thermal management requirements corresponding to the thermal management temperature boundary values of the fully charged state range, thereby improving the rationality of battery thermal management. The thermal management temperature boundary values of the fully charged state range are not fixed but vary. When the thermal management temperature boundary values of the fully charged state range are relatively high, the allowable operating temperature of the battery is relatively high, avoiding the situation in the related art where a relatively fixed temperature threshold is used for battery thermal management, resulting in the battery operating at a relatively fixed temperature all the time. Thus, the charging efficiency of the battery is improved, which is beneficial to enhancing the fast charging performance of the battery. Moreover, by performing thermal management of the battery according to the thermal management temperature boundary values of the fully charged state range, it is possible to avoid the temperature of the battery exceeding the thermal management temperature boundary value corresponding to the state of charge as much as possible, so that the battery still operates within a safe temperature range, reducing the probability of the battery experiencing thermal runaway, improving the reliability of the battery, and reducing the energy consumption of thermal management. In addition, the thermal management temperature boundary values of the fully charged state range are determined based on the self-heat generation start temperatures of at least two reference states of charge, enabling the temperature of the battery to not exceed the self-heat generation start temperature of the battery as much as possible, improving the safety of battery use, and eliminating the need to measure the self-heat generation start temperatures of all states of charge within the fully charged state range, reducing the establishment time of the thermal management temperature boundary values of the fully charged state range, and thus improving the establishment efficiency of the thermal management temperature boundary values of the fully charged state range.

[0083] In some embodiments, the thermal management temperature boundary values of the fully charged state range are determined based on the self-heat generation start temperatures of the reference battery at different states of charge. In this way, by performing thermal management of the battery according to the thermal management temperature boundary values of the fully charged state range, it is possible to avoid the self-heat generation reaction of the battery as much as possible and improve the reliability of the battery. Therefore, the allowable operating temperature of the battery in the low state of charge is greater than the allowable operating temperature of the battery in the high state of charge, avoiding the situation where the battery operates at a relatively low temperature all the time, thereby improving the fast charging performance of the battery to a certain extent.

[0084] In some embodiments, some limiting conditions of the thermal management temperature boundary values of the fully charged state range can be described:

[0085] In some embodiments, the thermal management temperature boundary values of the fully charged state range are determined based on the self-heat generation start temperatures of at least two reference states of charge of the battery; among them, at least two reference states of charge include the maximum state of charge in the fully charged state range.

[0086] In some embodiments, the thermal management temperature boundary values for the state of charge within the range from 0 to the minimum reference state of charge are all the self-heat release start temperatures of the minimum reference state of charge. In some embodiments, the self-heat release start temperatures of at least two reference states of charge are the thermal management temperature boundary values of at least two reference states of charge. In some embodiments, the thermal management temperature boundary values for the state of charge between two adjacent reference states of charge are determined based on the self-heat release start temperatures of the two adjacent reference states of charge.

[0087] In some embodiments, the thermal management temperature boundary values for the state of charge between two adjacent reference states of charge are determined based on the rate of change of the self-heat release start temperatures of the two adjacent reference states of charge. In some other embodiments, the thermal management temperature boundary values for the state of charge between two adjacent reference states of charge are the self-heat release start temperatures of the larger reference state of charge among the two adjacent reference states of charge.

[0088] The following describes the determination process of the thermal management temperature boundary values for the full state of charge range. In some embodiments, this determination process is performed by the battery management system. In some other embodiments, this determination process can be performed by any electronic device with information processing capabilities outside the battery management system (such as a computer device). When the electronic device obtains the thermal management temperature boundary values for the full state of charge range, it can send the thermal management temperature boundary values for the full state of charge range to the battery management system.

[0089] Figure 3 The flowchart of the thermal management method for the battery provided in the second embodiment is as Figure 3 shown. This method is applied to the battery management system. Figure 3 The difference between this embodiment and Figure 2 this embodiment is that S201 includes S2011 and S2012:

[0090] S2011. Obtain the self-heat release start temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include the maximum state of charge within the full state of charge range.

[0091] In some embodiments, the at least two reference states of charge can be preset values, and the interval between the at least two reference states of charge is a preset interval. Exemplarily, the at least two reference states of charge can include: 60%, 70%, 80%, 90%, and 100%. Another example, the at least two reference states of charge can include: 70%, 80%, 90%, and 100%. Another example, the at least two reference states of charge can include: 90% and 100%.

[0092] In some embodiments, the self-heat release start temperature of the smallest among at least two reference state of charge is greater than or equal to the maximum operating temperature of the battery, and the self-heat release start temperature of the second smallest among at least two reference state of charge is less than the maximum operating temperature of the battery. Exemplarily, the maximum operating temperature of the battery may be the temperature at which the electrolyte of the battery undergoes a reduction decomposition reaction. For example, the maximum operating temperature of the battery may be 80 degrees Celsius. Another example, the maximum operating temperature of the battery may be the maximum operating temperature in the battery attribute information.

[0093] In some embodiments, the self-heat release start temperature of at least two reference state of charge may be determined according to a preset interval between the reference state of charge and the maximum operating temperature of the battery. For example, in some embodiments, the determination method of the self-heat release start temperature of at least two reference state of charge is as follows: determine the preset interval between the reference state of charge (taking 10% as an example), determine the self-heat release start temperature when the state of charge of the battery is 100%, determine whether the self-heat release start temperature is greater than or equal to the maximum operating temperature of the battery, if not, then determine the self-heat release start temperature when the state of charge of the battery is 90%, determine whether the self-heat release start temperature is greater than or equal to the maximum operating temperature of the battery, if so, then take 90% and 100% as at least two reference state of charge, if not, then determine the self-heat release start temperature when the state of charge of the battery is 80%, and so on, so as to obtain at least two reference state of charge.

[0094] S2012. Determine the thermal management temperature boundary value of the full state of charge range according to the self-heat release start temperature of at least two reference state of charge.

[0095] In some embodiments, according to the self-heat release start temperature of at least two reference state of charge, the thermal management temperature boundary value of the full state of charge range may be determined by interpolation method.

[0096] In the technical solution of the embodiment of the present application, the thermal management temperature boundary value of the full state of charge range is determined according to the self-heat release start temperature of at least two reference state of charge, without measuring the self-heat release start temperature of all states of charge in the full state of charge range, reducing the establishment time of the thermal management temperature boundary value of the full state of charge range, thereby improving the establishment efficiency of the thermal management temperature boundary value of the full state of charge range.

[0097] In some embodiments, the thermal management temperature boundary value of the state of charge within the range from 0 to the smallest reference state of charge is determined to be the self-heat release start temperature of the smallest reference state of charge; the self-heat release start temperature of at least two reference state of charge is determined to be the thermal management temperature boundary value of at least two reference state of charge; according to the self-heat release start temperature of two adjacent reference state of charge, the thermal management temperature boundary value of the state of charge between two adjacent reference state of charge is determined.

[0098] For example, according to the self-heat generation start temperature of two adjacent reference state of charge (SOC), determining the thermal management temperature boundary value of the SOC between the two adjacent reference SOCs may include: determining the thermal management temperature boundary value of the SOC between the two adjacent reference SOCs by using interpolation method according to the self-heat generation start temperature of at least two reference SOCs.

[0099] In the technical solution of the embodiment of the present application, the thermal management temperature boundary value of the SOC within the range from 0 to the minimum reference SOC is determined as the self-heat generation start temperature of the minimum reference SOC, which improves the convenience of determining the thermal management temperature boundary value of each SOC within this interval; the self-heat generation start temperature of at least two reference SOCs is determined as the thermal management temperature boundary value of at least two reference SOCs, so as to ensure the accuracy of the thermal management temperature boundary value of at least two reference SOCs; according to the self-heat generation start temperature of two adjacent reference SOCs, determining the thermal management temperature boundary value of the SOC between the two adjacent reference SOCs, avoiding the interference of the self-heat generation start temperature of other reference SOCs outside the two adjacent reference SOCs on the determination of the thermal management temperature boundary value of the SOC between the two adjacent reference SOCs, thereby improving the accuracy of the determined thermal management temperature boundary value of the SOC between the two adjacent reference SOCs.

[0100] In some embodiments, according to the self-heat generation start temperature of two adjacent reference SOCs, determining the thermal management temperature boundary value of the SOC between the two adjacent reference SOCs includes: determining the thermal management temperature boundary value of the SOC between the two adjacent reference SOCs according to the change rate of the self-heat generation start temperature of the two adjacent reference SOCs.

[0101] In the technical solution of the embodiment of the present application, considering the gradual change process of the self-heat generation characteristics of the battery at different SOCs, the determination of the thermal management temperature boundary value is more in line with the actual thermal behavior of the battery, thereby improving the accuracy of the determined thermal management temperature boundary value of the SOC between the two adjacent reference SOCs.

[0102] In other embodiments, according to the self-heat generation start temperature of two adjacent reference SOCs, determining the thermal management temperature boundary value of the SOC between the two adjacent reference SOCs includes: determining the self-heat generation start temperature of the larger reference SOC among the two adjacent reference SOCs as the thermal management temperature boundary value of the SOC between the two adjacent reference SOCs.

[0103] In the technical solution of the embodiment of the present application, by determining the self-heat generation start temperature of the larger reference state of charge among two adjacent reference states of charge as the thermal management temperature boundary value of the state of charge between the two adjacent reference states of charge, the convenience of determining the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge is improved.

[0104] Figure 4 FIG. 4 is a schematic flowchart of the battery thermal management method provided for the third embodiment. This method is applied to a battery management system. Compared with Figure 2 the embodiment, the difference is that S201 includes S2013 and S2014:

[0105] S2013. Obtain the current state of health (SOH) of the battery.

[0106] The state of health of the battery refers to the ratio of the energy discharged from the fully charged state to the cut-off voltage at a certain rate under standard conditions to its corresponding nominal rated energy. The value range of the state of health of the battery is from 0 to 1.

[0107] In some embodiments, the current state of health of the battery can be determined according to at least one of the following: battery life, battery operation duration, battery charging times, battery cruising range, etc. For example, the current state of health of the battery can be determined according to the battery operation duration, and the battery operation duration can be the difference between the current time and the vehicle purchase time.

[0108] S2014. Determine the thermal management temperature boundary value of the full state of charge range that matches the current state of health from the mapping relationships of the obtained multiple states of health.

[0109] Wherein, the mapping relationship of each state of health includes: the corresponding relationship between the full state of charge range and the thermal management temperature boundary value under each state of health.

[0110] Exemplarily, the multiple states of health can include 1, and the intervals between adjacent states of health can be the same or different. For example, the multiple states of health can include 1, 0.95, 0.9, 0.85, 0.8, and 0.75.

[0111] Exemplarily, different health states have different corresponding relationships between the full charge state ranges and the thermal management temperature boundary values. In some embodiments, if a certain health state among multiple health states is the same as the current health state, then the corresponding relationship between the full charge state range of this health state and the thermal management temperature boundary value is determined as the thermal management temperature boundary value of the full charge state range. In other embodiments, the multiple health states are arranged in descending order. If all the multiple health states are different from the current health state, then a target health state that is less than the current health state for the first time is obtained, and the corresponding relationship between the full charge state range corresponding to this target health state and the thermal management temperature boundary value is determined as the thermal management temperature boundary value of the full charge state range.

[0112] In some embodiments, Figure 4 The solution of the embodiment can be combined with Figure 3 the solution of the embodiment. For example, obtain the self-heat release start temperature of at least two reference charge states of each health state of the battery under multiple health states; according to the self-heat release start temperature of at least two reference charge states of each health state, determine the thermal management temperature boundary value of the full charge state range of each health state, and the thermal management temperature boundary value of the full charge state range of each health state is the mapping relationship of each health state.

[0113] In the technical solution of the embodiment of the present application, from the mapping relationships of multiple health states, determine the thermal management temperature boundary value of the full charge state range that matches the current health state of the battery. Furthermore, the thermal management performed on the battery can also match the current health state of the battery, avoiding the situation where the health state of the battery decreases after long-term use, but still using the thermal management temperature boundary value of the full charge state range of a higher health state to perform thermal management on the battery, resulting in the occurrence of overheat of the battery. Therefore, the embodiment of the present application can improve the reliability of the battery.

[0114] Figure 5 It is a schematic flowchart of the thermal management method for the battery provided in the fourth embodiment. This method is applied to a battery management system. The difference between this method and Figure 2 the embodiment is that S201 includes S2015 to S2017:

[0115] S2015. Obtain the computing power of the battery management system and / or the attribute information of the battery.

[0116] In some embodiments, the computing power of the battery management system can be included in the attribute information of the battery management system. In other embodiments, the computing power of the battery management system can be the current remaining computing power of the battery management system. For example, the computing power can include a computing power value or a computing power score.

[0117] For the description of the attribute information of the battery, please refer to the above text and will not be elaborated here.

[0118] S2016. Determine the mapping type between the state of charge and the thermal management temperature boundary value according to the computing power of the battery management system and / or the attribute information of the battery.

[0119] In some embodiments, different mapping types may include different variation relationships. In some embodiments, determining the mapping type between the state of charge and the thermal management temperature boundary value may include: determining the mapping type between the state of charge and the thermal management temperature boundary value from multiple corresponding types. Exemplarily, the multiple corresponding types may include: the corresponding type of continuous thermal management temperature boundary value, the corresponding type of multi-stage thermal management temperature boundary value. Exemplarily, the corresponding type of multi-stage thermal management temperature boundary value may include at least one of the following: the corresponding type of five-stage thermal management temperature boundary value, the corresponding type of four-stage thermal management temperature boundary value, the corresponding type of three-stage thermal management temperature boundary value, the corresponding type of two-stage thermal management temperature boundary value, the corresponding type of stage thermal management temperature boundary value greater than five stages. Wherein, the thermal management temperature boundary value of each stage is the same.

[0120] In some embodiments, the variation fineness of the thermal management temperature boundary value in the corresponding type of continuous thermal management temperature boundary value is greater than that in the corresponding type of multi-stage thermal management temperature boundary value. In some embodiments, in the corresponding type of multi-stage thermal management temperature boundary value, the higher the number of stages, the finer the variation of the thermal management temperature boundary value.

[0121] In some embodiments, in the case where the variation of the thermal management temperature boundary value is finer, the thermal management temperature boundary value in the low state of charge is higher. Exemplarily, the low state of charge includes 0%. For example, the low state of charge includes 0% to 10%. For another example, the low state of charge includes 0% to 30%. For another example, the low state of charge includes 0% to 50%, etc., and the embodiments of the present application do not limit this.

[0122] For example, the multiple corresponding types may be respectively as follows Figures 10 to 12 as shown.

[0123] S2017. Obtain the thermal management temperature boundary value in the full state of charge range according to the mapping type.

[0124] In some embodiments, the thermal management temperature boundary value in the full state of charge range matches the mapping type.

[0125] In some embodiments, Figure 5 the embodiments of Figure 4 can be combined with the embodiments of

[0126] In the technical solution of the embodiment of the present application, according to the computing power of the battery management system, the mapping type between the state of charge and the thermal management temperature boundary value is determined. Thus, when the computing power of the battery management system is higher, the change of the thermal management temperature boundary value is more refined; when the computing power of the battery management system is lower, the change of the thermal management temperature boundary value is more concise. As a result, the battery management system can operate reasonably under different computing powers, improving the rationality of battery thermal management. According to the attribute information of the battery, the mapping type between the state of charge and the thermal management temperature boundary value is determined. Thus, when the attribute information of the battery indicates a higher quality of the battery, the thermal management temperature boundary value in the low state of charge is higher; when the attribute information of the battery indicates a lower quality of the battery, the thermal management temperature boundary value in the low state of charge is lower. In this way, refined thermal management based on the actual condition of the battery can improve the stability of battery operation.

[0127] Figure 6 FIG. 5 is a schematic flowchart of the thermal management method for the battery provided in the fifth embodiment. This method is applied to the battery management system. In this method, the target temperature boundary value includes the first temperature boundary value and the second temperature boundary value. The difference between this method and Figure 2 the embodiment is that S202 includes S2021 to S2022, and S203 includes S2031:

[0128] S2021: Determine the thermal management temperature boundary value corresponding to the current state of charge of the battery among the thermal management temperature boundary values in the full state-of-charge range as the first temperature boundary value.

[0129] For example, the thermal management temperature boundary values in the full state-of-charge range include the thermal management temperature boundary value at 0% state of charge, the thermal management temperature boundary value at 1% state of charge up to the thermal management temperature boundary value at 100% state of charge. When the current state of charge is 11%, determine the thermal management temperature boundary value at 11% state of charge as the first temperature boundary value. When the current state of charge changes to 12%, determine the thermal management temperature boundary value at 12% state of charge as the first temperature boundary value. In this way, every time the current state of charge changes, the first temperature boundary value can be determined according to the changed state of charge.

[0130] S2022: Determine the difference between the first temperature boundary value and a preset temperature offset value as the second temperature boundary value.

[0131] For example, every time the first temperature boundary value is determined, the second temperature boundary value is determined according to the first temperature boundary value.

[0132] In some embodiments, the preset temperature offset value can be a fixed offset value. In other embodiments, the preset temperature offset value can be a variable offset value. Exemplarily, the preset temperature offset value can be determined according to the state of charge of the battery. For example, the corresponding temperature offset value is determined according to the mapping relationship between the preset temperature offset value and the state of charge. For example, when the state of charge is less than 10% or greater than 90%, the temperature offset value is the first offset value, and when the state of charge is greater than or equal to 10% and less than or equal to 90%, the temperature offset value is the second offset value, and the first offset value is greater than the second offset value.

[0133] S2031. Perform thermal management on the battery according to the current temperature of the battery, the first temperature boundary value, and the second temperature boundary value.

[0134] In the technical solution of the embodiment of the present application, the first temperature boundary value and the second temperature boundary value of each state of charge are determined through the thermal management temperature boundary values in the full state-of-charge range. The second temperature boundary value is the difference between the first temperature boundary value and the preset temperature offset value. In this way, there are a first temperature boundary value and a second temperature boundary value with a difference of the temperature offset value for each state of charge, which is conducive to performing multiple levels of thermal management on the battery according to the current temperature of the battery, the first temperature boundary value, and the second temperature boundary value, and improving the effectiveness of thermal battery management.

[0135] In some embodiments, performing thermal management on the battery according to the current temperature of the battery, the first temperature boundary value, and the second temperature boundary value includes: when the current temperature is greater than or equal to the first temperature boundary value, performing thermal management on the battery in a first thermal management manner.

[0136] In some embodiments, the first thermal management manner may include at least one of the following: controlling the heat dissipation device of the battery to operate at a first operating power, controlling to reduce the charging rate of the battery by a first charging rate, and controlling to reduce the discharging rate of the battery by a first discharging rate.

[0137] In some embodiments, performing thermal management on the battery according to the current temperature of the battery, the first temperature boundary value, and the second temperature boundary value includes: when the current temperature is greater than or equal to the second temperature boundary value and less than the first temperature boundary value, performing thermal management on the battery in a second thermal management manner; wherein, the temperature drop rate of the battery under the first thermal management manner is greater than the temperature drop rate of the battery under the second thermal management manner.

[0138] In some embodiments, when the current temperature is less than the second temperature boundary value, thermal management of the battery includes not controlling the temperature of the battery. In other embodiments, when the current temperature is less than the second temperature boundary value, thermal management of the battery includes performing thermal management on the battery in a third thermal management mode, and the temperature decrease rate of the battery in the third thermal management mode is less than the temperature decrease rate of the battery in the second thermal management mode.

[0139] In some embodiments, the second thermal management mode may include at least one of the following: controlling the heat dissipation device of the battery to operate at a second operating power, controlling the charging rate of the battery to be reduced by a second charging rate, and controlling the discharging rate of the battery to be reduced by a second discharging rate. Among them, the first operating power is greater than the second operating power. Among them, the first charging rate is greater than the second charging rate. Among them, the first discharging rate is greater than the second discharging rate.

[0140] In some embodiments, the control types of the first control mode and the second control mode are the same. For example, the first control mode is to control the heat dissipation device of the battery to operate at a first operating power, and the second control mode is to control the heat dissipation device of the battery to operate at a second operating power. Another example is that the first control mode is to control the heat dissipation device of the battery to operate at a first operating power and control the charging rate of the battery to be reduced by a first charging rate, and the second control mode is to control the heat dissipation device of the battery to operate at a second operating power and control the charging rate of the battery to be reduced by a second charging rate.

[0141] In other embodiments, the first control mode may include the second control mode, and the first control mode has at least one more battery temperature reduction method than the second control mode. Exemplarily, the second control mode includes controlling the heat dissipation device of the battery to operate at a second operating power, and the first control mode includes controlling the heat dissipation device of the battery to operate at a second operating power and controlling the charging rate of the battery to be reduced by a first charging rate.

[0142] In the technical solution of the embodiments of the present application, when the current temperature of the battery is greater than or equal to the first temperature boundary value, it indicates that the probability of the battery having a thermal runaway risk is relatively high, and the first thermal management mode with a relatively large temperature decrease rate is adopted, so as to achieve rapid cooling of the battery; when the current temperature of the battery is between the second temperature boundary value and the first temperature boundary value, it indicates that the probability of the battery having a thermal runaway risk is relatively small, and it is switched to the second thermal management mode with a relatively small temperature decrease rate, so as to achieve gentle cooling of the battery, improve the pertinence of battery thermal management, and further improve the rationality of battery thermal management.

[0143] Figure 7 Schematic flow diagram of the thermal management method for the battery provided in the sixth embodiment. This method is applied to a battery management system. This method compared withFigure 2 The difference in the embodiment is that S203 includes S2032 to S2034.

[0144] S2032, when the battery is in a charging state, obtain the charging mode of the battery.

[0145] Exemplarily, the charging mode of the battery may include a slow charging mode (corresponding to charging level 1) or a fast charging mode. Exemplarily, the fast charging mode may include a fast charging mode corresponding to charging level 2, a supercharging mode corresponding to charging level 3, or a DC fast charging mode. The specific types of the fast charging mode in the embodiments of the present application are not limited. In some embodiments, wireless charging may be a slow charging mode or a fast charging mode according to the magnitude of the charging power.

[0146] S2033, when the charging mode of the battery is a slow charging mode, control the operation of the heat dissipation device of the battery according to the current temperature of the battery and the target temperature boundary value, and / or reduce the charging rate of the battery.

[0147] Exemplarily, when the charging mode of the battery is a slow charging mode, thermal management of the battery according to the current temperature and the target temperature boundary value includes controlling the operation of the heat dissipation device of the battery. Exemplarily, when the charging mode of the battery is a slow charging mode, thermal management of the battery according to the current temperature and the target temperature boundary value includes reducing the charging rate of the battery. Exemplarily, when the charging mode of the battery is a slow charging mode, thermal management of the battery according to the current temperature and the target temperature boundary value includes controlling the operation of the heat dissipation device of the battery and reducing the charging rate of the battery.

[0148] S2034, when the charging mode of the battery is a fast charging mode, control the operation of the heat dissipation device of the battery according to the current temperature of the battery and the target temperature boundary value.

[0149] In some embodiments, when the charging mode of the battery is a slow charging mode, control the operating power of the heat dissipation device of the battery to be the third operating power. When the charging mode of the battery is a fast charging mode, control the operating power of the heat dissipation device of the battery to be the fourth operating power. Among them, the magnitude relationship between the third operating power and the fourth operating power is determined according to the current temperature and the target temperature boundary value. Exemplarily, the third operating power is greater than the fourth operating power, or the third operating power is equal to the fourth operating power, or the third operating power is less than the fourth operating power. For example, in some embodiments, since the temperature rise rate of the battery is relatively high during fast charging of the battery, in order to avoid the battery having too high a temperature, the third operating power may be made less than the fourth operating power.

[0150] In some embodiments, Figure 7The solution in the embodiment can be combined with Figure 6 the solution in the embodiment. Exemplarily, according to the current temperature and the target temperature boundary value, thermal management of the battery is performed, including the following steps:

[0151] When the battery is in a charging state, obtain the charging mode of the battery.

[0152] When the charging mode of the battery is the slow charging mode and when the current temperature is greater than or equal to the first temperature boundary value, performing thermal management on the battery includes controlling the heat dissipation device of the battery to operate at the first operating power, and / or controlling the charging rate of the battery to be reduced by the first charging rate.

[0153] When the charging mode of the battery is the slow charging mode and when the current temperature is greater than or equal to the second temperature boundary value and less than the first temperature boundary value, performing thermal management on the battery includes controlling the heat dissipation device of the battery to operate at the second operating power, and / or controlling the charging rate of the battery to be reduced by the second charging rate. Wherein, the first operating power is greater than the second operating power, and the first charging rate is greater than the second charging rate.

[0154] When the charging mode of the battery is the fast charging mode and when the current temperature is greater than or equal to the first temperature boundary value, performing thermal management on the battery includes controlling the heat dissipation device of the battery to operate at the fifth operating power.

[0155] When the charging mode of the battery is the fast charging mode and when the current temperature is greater than or equal to the second temperature boundary value and less than the first temperature boundary value, performing thermal management on the battery includes controlling the heat dissipation device of the battery to operate at the sixth operating power. Wherein, the fifth operating power is greater than the sixth operating power.

[0156] In the technical solution of the embodiment of the present application, when the charging mode of the battery is the slow charging mode, a thermal management solution of reducing the charging rate of the battery can be considered, which is beneficial to reducing the cooling pressure of the heat dissipation device and improving the reliability of the battery during charging; when the charging mode of the battery is the fast charging mode, a thermal management solution considering the operation of the heat dissipation device is considered, so as to ensure the smooth progress of fast charging as much as possible and improve the charging efficiency of the battery.

[0157] Figure 8 It is a schematic flowchart of the thermal management method for the battery provided in the seventh embodiment, and this method is applied to the battery management system. Figure 8 The difference between the embodiment and Figure 2 the embodiment is that S203 includes S2035 to S2037.

[0158] S2035. Obtain the target temperature difference between the current temperature of the battery and the target temperature boundary value.

[0159] In some embodiments, Figure 8 the target temperature boundary value in the embodiment is the first temperature boundary value.

[0160] Exemplarily, the target temperature difference can be a positive value, 0, or a negative value.

[0161] In some embodiments, when the current temperature is greater than or equal to the second temperature boundary value, obtain the target temperature difference between the current temperature and the first temperature boundary value. Wherein, the second temperature boundary value is the difference between the first temperature boundary value and a preset temperature offset value.

[0162] In other embodiments, when the current temperature is greater than or equal to a preset temperature threshold, obtain the target temperature difference between the current temperature and the first temperature boundary value. Wherein, the preset temperature threshold is less than the first temperature boundary value. Exemplarily, the preset temperature threshold can be the most suitable operating temperature of the battery. For example, when the current temperature is greater than the most suitable operating temperature of the battery under the current state of charge, obtain the target temperature difference between the current temperature and the first temperature boundary value. Wherein, the most suitable operating temperature of the battery under the current state of charge is less than the first temperature boundary value. Exemplarily, a mapping relationship between the state of charge and the most suitable operating temperature of the battery can be stored in the battery management system, and the most suitable operating temperature of the battery under the current state of charge is determined according to this mapping relationship.

[0163] S2036. Determine the target operating power of the heat dissipation device according to the target temperature difference and the corresponding relationship between the operating power of the heat dissipation device of the battery and the temperature difference.

[0164] In some embodiments, in the corresponding relationship between the operating power of the heat dissipation device of the battery and the temperature difference, the operating power increases as the temperature difference increases.

[0165] In some embodiments, the corresponding relationship between the operating power of the heat dissipation device of the battery and the temperature difference can be pre-stored in the battery management system.

[0166] S2037. Control the heat dissipation device to operate at the target operating power.

[0167] In some embodiments, Figure 8 the embodiment can be combined with Figure 6 the embodiment. Exemplarily, according to the current temperature of the battery and the target temperature boundary value, thermal management of the battery can be achieved in the following manner:

[0168] Obtain the target temperature difference between the current temperature and the first temperature boundary value among the target temperature boundary values;

[0169] When the current temperature is greater than or equal to the first temperature boundary value, it is determined that the target temperature difference is greater than or equal to 0, and according to the target temperature difference and the corresponding relationship between the operating power of the battery's heat dissipation device and the temperature difference, it is determined that the target operating power of the heat dissipation device is greater than or equal to the first operating power; thermal management of the battery includes: controlling the heat dissipation device to operate at a target operating power greater than or equal to the first operating power;

[0170] When the current temperature is greater than or equal to the second temperature boundary value and less than the first temperature boundary value, it is determined that the target temperature difference is less than 0, and according to the target temperature difference and the corresponding relationship between the operating power of the battery's heat dissipation device and the temperature difference, it is determined that the target operating power of the heat dissipation device is greater than or equal to the second operating power and less than the first operating power; thermal management of the battery includes: controlling the heat dissipation device to operate at a target operating power greater than or equal to the second operating power and less than the first operating power.

[0171] Exemplarily, the target operating power can increase as the target temperature difference increases.

[0172] In some embodiments, Figure 8 the embodiments can be combined with Figure 7 the embodiments. Exemplarily, according to the current temperature of the battery and the target temperature boundary value, thermal management of the battery can be achieved in the following ways:

[0173] When the battery is in a charging state, obtain the charging mode of the battery;

[0174] Obtain the target temperature difference between the current temperature and the first temperature boundary value among the target temperature boundary values;

[0175] When the charging mode of the battery is the slow charging mode, according to the target temperature difference and the corresponding relationship between the operating power of the battery's heat dissipation device and the temperature difference, determine the target operating power of the heat dissipation device. Thermal management of the battery includes: controlling the heat dissipation device of the battery to operate at the target operating power, or controlling the heat dissipation device of the battery to operate at the target operating power and reducing the charging rate of the battery;

[0176] When the charging mode of the battery is the fast charging mode, according to the target temperature difference and the corresponding relationship between the operating power of the battery's heat dissipation device and the temperature difference, determine the target operating power of the heat dissipation device. Thermal management of the battery includes: controlling the heat dissipation device of the battery to operate at the target operating power.

[0177] In the technical solution of the embodiment of the present application, according to the target temperature difference between the current temperature of the battery and the target temperature boundary value, the target operating power of the heat dissipation device is determined. Thus, the target operating power of the heat dissipation device can be flexibly determined according to different target temperature differences. For example, when the target temperature difference is large, the target operating power of the heat dissipation device is also large; when the target temperature difference is small, the target operating power of the heat dissipation device is also small. Furthermore, precise battery thermal management can be achieved, the temperature fluctuation of the battery is reduced, and the reliability of the battery is improved.

[0178] Figure 9 FIG. 4 is a schematic flowchart of the battery thermal management method provided for the eighth embodiment. This method is applied to a battery management system. Compared with Figure 2 the embodiment, the difference is that before S202, the method further includes:

[0179] S901. Obtain the state of charge of multiple battery cells in the battery and the temperatures of the multiple battery cells.

[0180] In some embodiments, the battery management system can collect the voltages of multiple battery cells and the temperatures of the multiple battery cells, and the battery management system can determine the state of charge of the multiple battery cells according to the voltages of the multiple battery cells.

[0181] S902. Determine the maximum value among the states of charge of the multiple battery cells as the current state of charge of the battery, and determine the maximum value among the temperatures of the multiple battery cells as the current temperature of the battery.

[0182] In Figure 9 some other embodiments other than this, the average value among the states of charge of the multiple battery cells can be determined as the current state of charge, and the average value among the temperatures of the multiple battery cells can be determined as the current temperature.

[0183] In the technical solution of the embodiment of the present application, since the self-heating start temperature decreases as the state of charge increases, the maximum value among the states of charge of the multiple battery cells is determined as the current state of charge. Thus, the target temperature boundary value matching the current state of charge is the minimum temperature boundary value among the multiple temperature boundary values matching the states of charge of the multiple battery cells. Therefore, by performing thermal management on the battery according to this minimum temperature boundary value, the reliability of all battery cells in the battery can be improved; and, the maximum value among the temperatures of the multiple battery cells is determined as the current temperature. In this way, by performing thermal management on the battery according to the maximum value among the temperatures of the multiple battery cells, the reliability of all battery cells in the battery can be improved.

[0184] In some embodiments, by determining the thermal management temperature boundary values of the battery at different states of charge, precise dynamic regulation of the battery temperature based on the current state of charge of the battery and the thermal management temperature boundary values can be achieved, optimizing the thermal management strategy of the battery management system, facilitating the implementation of an intelligent water cooling control strategy, and ensuring that the battery operates within the range of the thermal management temperature boundary values throughout the state of charge usage interval through multi-stage / segmented temperature regulation, thereby reducing the risk of battery thermal runaway. By precisely setting the thermal management temperature boundary values at full state of charge, the operating temperature of the battery at low state of charge can be increased, the fast charging ability can be improved, and the energy consumption of thermal management can be reduced.

[0185] In some embodiments, a thermal management strategy for dynamically regulating a water cooling system by a battery management system based on the thermal management temperature boundary values at the state of charge is provided. The self-heat release start temperature of a reference battery at different states of charge is measured by an adiabatic calorimeter to obtain the thermal management temperature boundary value of the battery at full state of charge. Among them, the adiabatic calorimeter is used to safely measure the heat released and the heat release rate during the storage and handling of chemical substances. Among them, the self-heat release start temperature refers to the temperature at which the self-heat release reaction in the material begins during the heat treatment process. Among them, self-heat release refers to the spontaneous exothermic reaction that occurs in the material under specific conditions.

[0186] In some embodiments, the thermal management temperature boundary values used by the battery management system for battery thermal management are determined based on the self-heat release start temperatures obtained at different states of charge.

[0187] In some embodiments, the thermal management temperature boundary values in the full state of charge range are the thermal management temperature boundary values that vary with the state of charge.

[0188] In some embodiments, the thermal management strategy of the battery management system can be determined based on the self-heat release start temperatures at different states of charge. Additionally, by setting thermal management temperature boundary values at multiple stages, with the thermal management temperature boundary values being the same for each stage, a multi-stage / segmented thermal management strategy can be achieved.

[0189] In some embodiments, the battery management system's thermal management of the battery should control the actual temperature of the battery within the thermal management temperature boundary values as much as possible to improve the reliability of the battery.

[0190] In some embodiments, by precisely setting the thermal management temperature boundary values at full state of charge, the thermal management strategy of the battery management system is optimized, an intelligent water cooling control strategy is implemented, and a multi-stage / segmented thermal management strategy is achieved, such that the battery operates as much as possible below the thermal management temperature boundary values throughout the full state of charge usage interval.

[0191] In some embodiments, by precisely setting the thermal management temperature boundary values at full state of charge, the operating temperature of the battery at low state of charge can be increased, the fast charging ability can be improved, and the energy consumption of thermal management can be reduced.

[0192] In some embodiments, by setting the precise thermal management temperature boundary value of the full state of charge, the water-cooling strategy is effectively activated, avoiding battery thermal abuse and enhancing the safety and reliability of the battery.

[0193] In some embodiments, the adiabatic calorimeter is used to test the self-heating start temperature corresponding to different states of charge of the battery, which is the reliable operating boundary temperature of the battery at a specific state of charge, and then the thermal management temperature boundary value of the battery at the full state of charge is obtained.

[0194] In some embodiments, the thermal management temperature boundary value of the battery at the full state of charge is input into the water-cooling control system of the battery management system, and the battery is controlled to operate as much as possible below the thermal management temperature boundary value, so that the battery does not generate self-heating reactions as much as possible, improving the reliability of the battery.

[0195] In some embodiments, the adiabatic calorimeter is used to measure the self-heating start temperature of the battery at different states of charge, that is, the self-heating start temperature of the reference state of charge. The thermal management temperature boundary value of the full state of charge is determined according to the self-heating start temperature of the reference state of charge. Based on the thermal management temperature boundary values of different states of charge in the full state of charge, the thermal management system of the battery management system makes the battery temperature as low as possible below the thermal management temperature boundary value of the state of charge it is in. According to the battery thermal management temperature boundary value, the battery temperature is monitored in real time, realizing the dynamic adjustment of the battery temperature control under different state-of-charge conditions, achieving multi-stage / segmented temperature regulation, and enhancing the thermal management reliability of the battery management system.

[0196] In some embodiments, the adiabatic calorimeter can provide an (approximate) adiabatic environment. The battery is placed in the calorimetry chamber of the instrument, and the battery is step-heated through the "Heat - Wait - Seek" mode to simulate the thermal runaway process of the battery in a state of no heat exchange with the environment, and record the temperature change of the battery in the adiabatic environment. Exemplarily, the battery is suspended in the calorimetry chamber (or placed on a bracket), and the temperature control thermocouple of the adiabatic calorimeter is firmly fixed at the center position of the large surface of the battery surface. After the test starts, the battery is in the adiabatic environment in the calorimetry chamber of the adiabatic calorimeter, with no heat exchange with the surrounding environment. The adiabatic calorimeter thermally triggers the battery under test by means of "step temperature rise". At each temperature step, when the battery and the ambient temperature are fully balanced and stable, the self-heating rate (SHR) of the battery is retrieved. If the SHR is less than or equal to a predetermined value (for example, 0.02 °C / min), it is determined that no self-heating reaction has occurred inside the battery, and the next temperature step is continued until the SHR is greater than the predetermined value, that is, a self-heating reaction starts inside the battery, and the start temperature when the SHR is greater than the predetermined value is recorded, which is the self-heating start temperature.

[0197] In some embodiments, an adiabatic calorimeter test is performed on the battery to obtain the self-heat generation start temperature of the battery at a state of charge (SOC) from 0% to 100%, thereby obtaining the safety temperature usage boundary at the fully charged state. In other embodiments, an adiabatic calorimeter test is performed on the battery to obtain the self-heat generation start temperatures at at least two reference states of charge. Based on the self-heat generation start temperatures at the at least two reference states of charge, the thermal management temperature boundary value within the fully charged state range is determined.

[0198] The thermal management temperature boundary values corresponding to different states of charge of the battery are input into the battery management system's thermal management system. Based on the thermal management temperature boundary values, continuous hierarchical regulation of the battery temperature at the fully charged state is achieved, realizing precise and dynamic regulation of thermal management.

[0199] Figure 10 Schematic diagram of the thermal management temperature boundary value within the fully charged state range provided for the first embodiment, as Figure 10 shown. The horizontal axis represents the state of charge, and the vertical axis represents the thermal management temperature boundary value (unit: °C). The thermal management temperature boundary value for the state of charge from 0% to 60% is the self-heat generation start temperature at 60% state of charge. The thermal management temperature boundary values for 70%, 80%, 90%, and 100% are the self-heat generation start temperatures at 70%, 80%, 90%, and 100% state of charge respectively. The thermal management temperature boundary value for the state of charge in the interval (60%, 70%) is determined according to the change rate of the self-heat generation start temperatures at 60% and 70% state of charge. The thermal management temperature boundary value for the interval (70%, 80%) is determined according to the change rate of the self-heat generation start temperatures at 70% and 80% state of charge. The thermal management temperature boundary value for the interval (80%, 90%) is determined according to the change rate of the self-heat generation start temperatures at 80% and 90% state of charge. The thermal management temperature boundary value for the interval (90%, 100%) is determined according to the change rate of the self-heat generation start temperatures at 90% and 100% state of charge.

[0200] Figure 11 Schematic diagram of the thermal management temperature boundary value within the fully charged state range provided for the second embodiment, as Figure 11 shown. The horizontal axis represents the state of charge, and the vertical axis represents the thermal management temperature boundary value (unit: °C). The thermal management temperature boundary value for the state of charge in the interval [0, 70%] is the self-heat generation start temperature at 70% state of charge. The thermal management temperature boundary value for the state of charge in the interval (70%, 80%] is the self-heat generation start temperature at 80% state of charge. The thermal management temperature boundary value for the state of charge in the interval (80%, 90%] is the self-heat generation start temperature at 90% state of charge. The thermal management temperature boundary value for the state of charge in the interval (90%, 100%] is the self-heat generation start temperature at 100% state of charge.

[0201] In this way, by storing the self-heat release start temperatures at 70%, 80%, 90%, and 100% state of charge in the battery management system, the battery management system can obtain the thermal management temperature boundary values for the full state of charge range (i.e., the thermal management temperature boundary values for the four stages). Based on the thermal management temperature boundary values for the four stages, the battery management system can implement four-stage battery thermal management.

[0202] Figure 12 Schematic diagram of the thermal management temperature boundary values for the full state of charge range provided for the third embodiment, as Figure 12 shown. The horizontal axis represents the state of charge, and the vertical axis represents the thermal management temperature boundary value (unit: °C). The thermal management temperature boundary value for the state of charge in the range [0, 90%] is the self-heat release start temperature at 90% state of charge, and the thermal management temperature boundary value for the state of charge in the range (90%, 100%] is the self-heat release start temperature at 100% state of charge.

[0203] In this way, by storing the self-heat release start temperatures at 90% and 100% state of charge in the battery management system, the battery management system can obtain the thermal management temperature boundary values for the full state of charge range (i.e., the thermal management temperature boundary values for the two stages). Based on the thermal management temperature boundary values for the two stages, the battery management system can implement two-stage battery thermal management.

[0204] Based on the same inventive concept, the embodiments of the present application also provide a battery thermal management device for implementing the battery thermal management method involved above. The solution provided by this device to solve the problem is similar to the solution described in the above method. Therefore, the specific limitations in one or more of the following embodiments of the battery thermal management device can refer to the limitations on the battery thermal management method in the above text and will not be elaborated here.

[0205] In an exemplary embodiment, Figure 13 Schematic diagram of the structure of the battery thermal management device provided for some embodiments, as Figure 13 shown. The battery thermal management device 1300 includes:

[0206] An acquisition module 1301, configured to acquire the thermal management temperature boundary values for the full state of charge range; wherein, the thermal management temperature boundary values for the full state of charge range are determined according to the self-heat release start temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include the maximum state of charge in the full state of charge range; a determination module 1302, configured to determine the target temperature boundary value according to the current state of charge of the battery and the thermal management temperature boundary values for the full state of charge range; a thermal management module 1303, configured to perform thermal management on the battery according to the current temperature of the battery and the target temperature boundary value.

[0207] In some embodiments, the obtaining module 1301 is further configured to: obtain the self-heat generation start temperature of at least two reference state of charge of the battery; the at least two reference state of charge includes the maximum state of charge in the full state of charge range; determine the thermal management temperature boundary value of the full state of charge range according to the self-heat generation start temperature of the at least two reference state of charge.

[0208] In some embodiments, the obtaining module 1301 is further configured to: determine the thermal management temperature boundary value of the state of charge within the range from 0 to the minimum reference state of charge as the self-heat generation start temperature of the minimum reference state of charge; determine the thermal management temperature boundary value of the at least two reference state of charge as the self-heat generation start temperature of the at least two reference state of charge; determine the thermal management temperature boundary value of the state of charge between two adjacent reference state of charge according to the self-heat generation start temperature of the two adjacent reference state of charge.

[0209] In some embodiments, the obtaining module 1301 is further configured to: determine the thermal management temperature boundary value of the state of charge between two adjacent reference state of charge according to the change rate of the self-heat generation start temperature of the two adjacent reference state of charge.

[0210] In some embodiments, the obtaining module 1301 is further configured to: determine the thermal management temperature boundary value of the state of charge between two adjacent reference state of charge as the self-heat generation start temperature of the larger reference state of charge of the two adjacent reference state of charge.

[0211] In some embodiments, the obtaining module 1301 is further configured to: obtain the current health state of the battery; determine the thermal management temperature boundary value of the full state of charge range that matches the current health state from the obtained mapping relationships of multiple health states; wherein, the mapping relationship of each health state includes: the corresponding relationship between the full state of charge range and the thermal management temperature boundary value under each health state.

[0212] In some embodiments, the obtaining module 1301 is further configured to: obtain the computing power of the battery management system and / or the attribute information of the battery; determine the mapping type between the state of charge and the thermal management temperature boundary value according to the computing power of the battery management system and / or the attribute information of the battery; obtain the thermal management temperature boundary value of the full state of charge range according to the mapping type.

[0213] In some embodiments, the target temperature boundary value includes a first temperature boundary value and a second temperature boundary value; the determining module 1302 is configured to: determine, as the first temperature boundary value, the thermal management temperature boundary value corresponding to the current state of charge of the battery among the thermal management temperature boundary values within the full state of charge range; determine the difference between the first temperature boundary value and a preset temperature offset value as the second temperature boundary value; the thermal management module 1303 is further configured to perform thermal management on the battery according to the current temperature of the battery, the first temperature boundary value, and the second temperature boundary value.

[0214] In some embodiments, the thermal management module 1303 is further configured to: when the current temperature is greater than or equal to the first temperature boundary value, perform thermal management on the battery in a first thermal management manner; when the current temperature is greater than or equal to the second temperature boundary value and less than the first temperature boundary value, perform thermal management on the battery in a second thermal management manner; wherein, the temperature decrease rate of the battery in the first thermal management manner is greater than the temperature decrease rate of the battery in the second thermal management manner.

[0215] In some embodiments, the thermal management module 1303 is further configured to: when the battery is in a charging state, obtain the charging mode of the battery; when the charging mode of the battery is a slow charging mode, control the operation of the heat dissipation device of the battery and / or reduce the charging rate of the battery according to the current temperature of the battery and the target temperature boundary value; when the charging mode of the battery is a fast charging mode, control the operation of the heat dissipation device of the battery according to the current temperature of the battery and the target temperature boundary value.

[0216] In some embodiments, the target temperature boundary value includes a first temperature boundary value; the thermal management module 1303 is further configured to: obtain the target temperature difference between the current temperature of the battery and the first temperature boundary value; determine the target operating power of the heat dissipation device according to the target temperature difference and the corresponding relationship between the operating power of the heat dissipation device of the battery and the temperature difference; control the heat dissipation device to operate at the target operating power.

[0217] In some embodiments, the obtaining module 1301 is further configured to: obtain the state of charge of multiple battery cells in the battery and the temperatures of the multiple battery cells; the determining module 1302 is further configured to: determine the maximum value among the states of charge of the multiple battery cells as the current state of charge, and determine the maximum value among the temperatures of the multiple battery cells as the current temperature.

[0218] The description of the above device embodiments is similar to the description of the above method embodiments and has similar beneficial effects to the method embodiments. For the technical details not disclosed in the device embodiments of the present application, please refer to the description of the method embodiments of the present application for understanding.

[0219] Each module in the thermal management device of the above battery can be implemented in whole or in part by software, hardware, or a combination thereof. Each of the above modules can be embedded in the processor in the battery management system in hardware form or independent of it, or stored in the memory in the battery management system in software form, so that the processor can call and execute the operations corresponding to each of the above modules.

[0220] In an exemplary embodiment, Figure 14 FIG. 5 is a schematic structural diagram of a battery management system provided for some embodiments. Exemplarily, the battery management system includes a processor, a memory, an input / output interface (Input / Output, abbreviated as I / O), and a communication interface. Among them, the processor, the memory, and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the battery management system is used to provide computing and control capabilities. The memory of the battery management system includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores a computer program. The internal memory provides an environment for the operation of the computer program in the non-volatile storage medium. The input / output interface of the battery management system is used for exchanging information between the processor and external devices. The communication interface of the battery management system is used for communicating with an external terminal through a network connection. When the computer program is executed by the processor, it realizes a thermal management method for a battery.

[0221] Those skilled in the art can understand that Figure 14 the structure shown in FIG. 5 is only a block diagram of some structures related to the solution of the present application, and does not constitute a limitation on the battery management system to which the solution of the present application is applied. The specific battery management system may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0222] For example, the battery management system includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, it realizes the steps of the method in any of the above embodiments.

[0223] For example, in an exemplary embodiment, when the processor is used to execute the computer program, it realizes: obtaining the thermal management temperature boundary value of the full charge state range; determining the target temperature boundary value according to the current charge state of the battery and the thermal management temperature boundary value of the full charge state range; and performing thermal management on the battery according to the current temperature of the battery and the target temperature boundary value.

[0224] In some embodiments, a vehicle is further provided. The vehicle includes a battery and the above battery management system; the battery is connected to the battery management system. In some embodiments, the vehicle may further include a heat dissipation device. The heat dissipation device is disposed on the surface of the battery, and the heat dissipation device is connected to the battery management system.

[0225] In some embodiments, a computer-readable storage medium is provided, and when the computer program is executed by a processor, the steps of the method provided in any of the above embodiments are implemented.

[0226] For example, in an exemplary embodiment, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented: obtaining the thermal management temperature boundary value of the full state of charge range; determining the target temperature boundary value according to the current state of charge of the battery and the thermal management temperature boundary value of the full state of charge range; performing thermal management on the battery according to the current temperature of the battery and the target temperature boundary value.

[0227] In one embodiment, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps of the method provided in any of the above embodiments are implemented.

[0228] For example, in an exemplary embodiment, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the following steps are implemented: obtaining the thermal management temperature boundary value of the full state of charge range; determining the target temperature boundary value according to the current state of charge of the battery and the thermal management temperature boundary value of the full state of charge range; performing thermal management on the battery according to the current temperature of the battery and the target temperature boundary value.

[0229] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods.

[0230] The processor, each functional module or each functional unit in any embodiment of the present application may include any one or more of the following integrations: general-purpose processor, application specific integrated circuit (ASIC), digital signal processor (DSP), digital signal processing device (DSPD), programmable logic device (PLD), field programmable gate array (FPGA), central processing unit (CPU), graphics processing unit (GPU), embedded neural network processor (neural-network processing units, NPU), controller, microcontroller, microprocessor, programmable logic device, discrete gate or transistor logic device, discrete hardware component, quantum computing-based data processing logic, artificial intelligence (AI) processor, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0231] The memory or computer-readable storage medium in any embodiment of the present application may include at least one of non-volatile memory and volatile memory. The non-volatile memory includes the integration of one or more of the following: Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Ferromagnetic Random Access Memory (FRAM), Flash Memory, magnetic surface memory, optical disc, Compact Disc Read-Only Memory (CD-ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, Resistive Random Access Memory (ReRAM), Magnetoresistive Random Access Memory (MRAM), Ferroelectric Random Access Memory (FRAM), Phase Change Memory (PCM), graphene memory, volatile memory, etc. The volatile memory includes the integration of one or more of the following: Random Access Memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM), etc.

[0232] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope recorded in the present application.

[0233] The above embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the appended claims.

Claims

1. A thermal management method for a battery, characterized in that, The method includes: Obtaining the thermal management temperature boundary values for the full state of charge (SOC) range; wherein, the thermal management temperature boundary values for the full SOC range are determined based on the self-heat generation start temperatures of at least two reference SOCs of the battery; the at least two reference SOCs include the maximum SOC in the full SOC range, and among the at least two reference SOCs, the self-heat generation start temperature of the minimum reference SOC is greater than or equal to the maximum operating temperature of the battery, and the self-heat generation start temperatures of the other reference SOCs except the minimum reference SOC are all less than the maximum operating temperature of the battery; Performing thermal management on the battery according to the thermal management temperature boundary values for the full SOC range; Among them, the thermal management temperature boundary values within the range from 0 to the minimum reference SOC are all obtained based on the self-heat generation start temperature of the minimum reference SOC; within the range from the minimum reference SOC to the maximum SOC in the full SOC range, the thermal management temperature boundary values for the SOCs between two adjacent reference SOCs are all obtained based on the self-heat generation start temperature of the larger reference SOC among the two adjacent reference SOCs.

2. The method according to claim 1, wherein The obtaining of the thermal management temperature boundary values for the full SOC range includes: Obtaining the self-heat generation start temperatures of at least two reference SOCs of the battery; the at least two reference SOCs include the maximum SOC in the full SOC range; Determining the thermal management temperature boundary values for the full SOC range according to the self-heat generation start temperatures of the at least two reference SOCs.

3. The method according to claim 2, wherein The determining of the thermal management temperature boundary values for the full SOC range according to the self-heat generation start temperatures of the at least two reference SOCs includes: Determining the thermal management temperature boundary values for the SOCs within the range from 0 to the minimum reference SOC as the self-heat generation start temperature of the minimum reference SOC; Determining the self-heat generation start temperatures of the at least two reference SOCs as the thermal management temperature boundary values for the at least two reference SOCs; Determining the thermal management temperature boundary values for the SOCs between two adjacent reference SOCs according to the self-heat generation start temperatures of the two adjacent reference SOCs.

4. The method according to claim 3, characterized in that, The determining of the thermal management temperature boundary values for the SOCs between two adjacent reference SOCs according to the self-heat generation start temperatures of the two adjacent reference SOCs includes: Determining the self-heat generation start temperature of the larger reference SOC among the two adjacent reference SOCs as the thermal management temperature boundary value for the SOCs between the two adjacent reference SOCs.

5. The method according to claim 1, characterized in that, The obtaining of the thermal management temperature boundary values for the full SOC range includes: Obtaining the current health state of the battery; Determining the thermal management temperature boundary values for the full SOC range that match the current health state from the obtained mapping relationships of multiple health states; wherein, each mapping relationship of the health state includes the corresponding relationship between the full SOC range and the thermal management temperature boundary value under each health state.

6. The method according to claim 1, characterized in that Obtaining the thermal management temperature boundary values for the full state of charge range includes: Obtaining the computing power of the battery management system and / or the attribute information of the battery; Determining the mapping type between the state of charge and the thermal management temperature boundary values according to the computing power of the battery management system and / or the attribute information of the battery; Obtaining the thermal management temperature boundary values for the full state of charge range according to the mapping type.

7. The method according to any one of claims 1 to 6, characterized in that, Performing thermal management on the battery according to the thermal management temperature boundary values for the full state of charge range includes: Determining the thermal management temperature boundary value corresponding to the current state of charge of the battery among the thermal management temperature boundary values for the full state of charge range as the first temperature boundary value; Determining the difference between the first temperature boundary value and a preset temperature offset value as the second temperature boundary value; Performing thermal management on the battery according to the current temperature of the battery, the first temperature boundary value, and the second temperature boundary value.

8. The method according to claim 7, characterized in that, Performing thermal management on the battery according to the current temperature of the battery, the first temperature boundary value, and the second temperature boundary value includes: When the current temperature is greater than or equal to the first temperature boundary value, performing thermal management on the battery in a first thermal management manner; When the current temperature is greater than or equal to the second temperature boundary value and less than the first temperature boundary value, performing thermal management on the battery in a second thermal management manner; Wherein, the temperature decrease rate of the battery under the first thermal management manner is greater than the temperature decrease rate of the battery under the second thermal management manner.

9. The method according to any one of claims 1 to 6, characterized in that Performing thermal management on the battery according to the thermal management temperature boundary values for the full state of charge range includes: When the battery is in a charging state, obtaining the charging mode of the battery; When the charging mode of the battery is a slow charging mode, controlling the operation of the heat dissipation device of the battery and / or reducing the charging rate of the battery according to the current temperature of the battery and the thermal management temperature boundary values for the full state of charge range; When the charging mode of the battery is a fast charging mode, controlling the operation of the heat dissipation device of the battery according to the current temperature of the battery and the thermal management temperature boundary values for the full state of charge range.

10. The method according to any one of claims 1 to 6, characterized in that, Performing thermal management on the battery according to the thermal management temperature boundary values for the full state of charge range includes: Obtaining the target temperature difference between the current temperature of the battery and the thermal management temperature boundary values for the full state of charge range; Determining the target operating power of the heat dissipation device according to the target temperature difference and the corresponding relationship between the operating power of the heat dissipation device of the battery and the temperature difference; Controlling the heat dissipation device to operate at the target operating power.

11. The method according to any one of claims 1 to 6, characterized in that, The method further includes: Obtaining the state of charge of multiple battery cells in the battery and the temperatures of the multiple battery cells; Determining the maximum value among the states of charge of the multiple battery cells as the current state of charge, and determining the maximum value among the temperatures of the multiple battery cells as the current temperature.

12. The method according to any one of claims 1 to 6, characterized in that The self-heat generation start temperatures of the at least two reference states of charge are obtained through the following steps: (1) Using the maximum state of charge as the current detection point; (2) Determine the self-heat generation start temperature of the current detection point; (3) When the self-heat generation start temperature of the current detection point is less than the maximum operating temperature of the battery, use the next detection point of the current detection point as the new current detection point, and return to step (2); (4) When the self-heat generation start temperature of the current detection point is greater than or equal to the maximum operating temperature of the battery, determine the self-heat generation start temperature of the currently obtained current detection point as the self-heat generation start temperature of the at least two reference state of charge.

13. A thermal management device for a battery, characterized in that, The thermal management device of the battery includes: An acquisition module, configured to acquire the thermal management temperature boundary values within the full state of charge range; wherein, the thermal management temperature boundary values within the full state of charge range are determined according to the self-heat generation start temperatures of at least two reference state of charge of the battery; the at least two reference state of charge include the maximum state of charge within the full state of charge range, and among the at least two reference state of charge, the self-heat generation start temperature of the minimum reference state of charge is greater than or equal to the maximum operating temperature of the battery, and the self-heat generation start temperatures of other reference state of charge except the minimum reference state of charge are all less than the maximum operating temperature of the battery; A thermal management module, configured to perform thermal management on the battery according to the thermal management temperature boundary values within the full state of charge range; Among them, the thermal management temperature boundary values within the range from 0 to the minimum reference state of charge are all obtained according to the self-heat generation start temperature of the minimum reference state of charge; within the range from the minimum reference state of charge to the maximum state of charge within the full state of charge range, the thermal management temperature boundary values of the states of charge between two adjacent reference state of charge are all obtained according to the self-heat generation start temperature of the larger reference state of charge among the two adjacent reference state of charge.

14. A battery management system, comprising a memory and a processor, the memory storing a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 12.

15. A vehicle, characterized in that, The vehicle includes a battery and the battery management system according to claim 14; the battery is connected to the battery management system.

16. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 12.

17. A computer program product comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 12.

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