Thermal management method, device and system of battery, vehicle, storage medium and product

Abstract

The invention relates to a thermal management method, device and system of a battery, a vehicle, a storage medium and a product. The method comprises the following steps: acquiring a thermal management temperature boundary value in a full charge state range; wherein the thermal management temperature boundary value of the full state-of-charge range is determined according to the self-heat-release initial temperature of at least two reference states of charge of the battery; the at least two reference states of charge comprise a maximum state of charge in a full state of charge range; determining a target temperature boundary value according to the current charge state of the battery and the thermal management temperature boundary value in 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. By adopting the method, the rationality of battery thermal management can be improved.

Description

Technical Field

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

[0002] With the development of new energy technology, batteries, as the core part of energy storage and conversion, are increasingly being used. Batteries will continuously generate heat during operation. As the heat increases, the operating temperature of the battery also increases. Excessively high operating temperatures not only accelerate the physical and chemical changes of the battery's internal materials, shortening the battery's life, but may also cause the battery to produce thermal runaway reactions. Therefore, it is very important to control the battery temperature.

[0003] However, in the related art, the control scheme of battery temperature is unreasonable, which affects the working performance of the battery. Summary of the invention

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

[0005] In a first aspect, the present application provides a method for thermal management of a battery, the method comprising: obtaining a thermal management temperature boundary value for a full state of charge range; wherein the thermal management temperature boundary value for the full state of charge range is determined based on the self-heating starting temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include a maximum state of charge in the full state of charge range; determining a target temperature boundary value based on the current state of charge of the battery and the thermal management temperature boundary value for the full state of charge range; and thermally managing the battery based on the current temperature of the battery and the target temperature boundary value.

[0006] In the technical solution of the embodiment of the present application, the thermal management of the battery can be flexibly performed according to the current state of charge of the battery, the current temperature and the accurately set thermal management temperature boundary value of the full state of charge 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 value of the full state of charge range, thereby improving the rationality of the thermal management of the battery; the thermal management temperature boundary value of the full state of charge range is not static, but varies, then when the thermal management temperature boundary value of the full state of charge range is high, the allowable operating temperature of the battery is higher, avoiding the use of a relatively fixed temperature threshold for thermal management of the battery in the related art, resulting in the battery always operating at a relatively fixed temperature, thereby improving the charging efficiency of the battery, which is beneficial to improving the battery Fast charging performance; and, the battery is thermally managed according to the thermal management temperature boundary value of the full charge state range, so as to avoid the battery temperature exceeding the thermal management temperature boundary value under the corresponding charge state 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 value of the full charge state range is determined based on the self-heating starting temperatures of at least two reference charge states, so that the battery temperature will not exceed the self-heating starting temperature of the battery as much as possible, thereby improving the safety of battery use, and there is no need to measure the self-heating starting temperatures of all charge states under the full charge range, which reduces the time for establishing the thermal management temperature boundary value of the full charge state range, thereby improving the efficiency of establishing the thermal management temperature boundary value of the full charge state range.

[0007] In some embodiments, obtaining the thermal management temperature boundary value of the full state of charge range includes: obtaining the self-heating starting 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; and determining the thermal management temperature boundary value of the full state of charge range according to the self-heating starting temperatures of the at least two reference states of charge. 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-heating starting temperatures of at least two reference states of charge, without measuring the self-heating starting temperatures of all states of charge in the full charge range, which reduces the time for establishing the thermal management temperature boundary value of the full state of charge range, thereby improving the efficiency of establishing the thermal management temperature boundary value of the full state of charge range.

[0008] In some embodiments, the thermal management temperature boundary value of the entire charge state range is determined based on the self-heating starting temperatures of at least two reference charge states, including: determining the thermal management temperature boundary values ​​of the charge states within the range of 0 to the minimum reference charge state as the self-heating starting temperature of the minimum reference charge state; determining the self-heating starting temperatures of at least two reference charge states as the thermal management temperature boundary values ​​of at least two reference charge states; determining the thermal management temperature boundary value of the charge state between two adjacent reference charge states based on the self-heating starting temperatures of at least two reference charge states. In the technical solution of the embodiment of the present application, the thermal management temperature boundary values ​​of the charge states within the range of 0 to the minimum reference charge state are all determined as the self-heating starting temperature of the minimum reference charge state, thereby improving the convenience of determining the thermal management temperature boundary values ​​of each charge state within this interval; the self-heating starting temperatures of at least two reference charge states are determined as the thermal management temperature boundary values ​​of at least two reference charge states, thereby ensuring the accuracy of the thermal management temperature boundary values ​​of at least two reference charge states; based on the self-heating starting temperatures of two adjacent reference charge states, the thermal management temperature boundary value of the charge state between two adjacent reference charge states is determined, thereby avoiding the self-heating starting temperatures of other reference charge states other than the two adjacent reference charge states from interfering with the determination of the thermal management temperature boundary value of the charge state between the two adjacent reference charge states, thereby improving the accuracy of the determined thermal management temperature boundary value of the charge state between the two adjacent reference charge states.

[0009] In some embodiments, the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge is determined according to the self-heating starting temperatures of the two adjacent reference states of charge, including: determining the thermal management temperature boundary value of the state of charge between the two adjacent reference states of charge according to the rate of change of the self-heating starting temperatures of the two adjacent reference states of charge. In the technical solution of the embodiment of the present application, the gradual change process of the self-heating characteristics of the battery under different states of charge is taken into account, so that 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 thermal management temperature boundary value of the state of charge between the two adjacent reference states of charge.

[0010] In some embodiments, determining a thermal management temperature boundary value of a state of charge between two adjacent reference states of charge based on the self-heating starting temperatures of the two adjacent reference states of charge includes: determining the self-heating starting temperature of the larger reference state of charge in the 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. In the technical solution of the embodiment of the present application, by determining the self-heating starting temperature of the larger reference state of charge in the 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 the 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 the thermal management temperature boundary value of the full state of charge range that matches the current health state from the mapping relationship of the obtained 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 in each health state. In the technical solution of the embodiment of the present application, the thermal management temperature boundary value of the full state of charge range that matches the current health state of the battery is determined from the mapping relationship of multiple health states, and then the thermal management of the battery can also match the current health state of the battery, avoiding the battery health state after long-term use. The battery is still thermally managed using the thermal management temperature boundary value of the full state of charge range of a higher health state, resulting in battery overheating. Therefore, the embodiment of the present application can improve the reliability of the battery.

[0012] In some embodiments, obtaining the thermal management temperature boundary value of 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 of 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; and obtaining the thermal management temperature boundary value of the full state of charge range according to the mapping type. In the technical solution of the embodiment of the present application, the mapping type of the state of charge and the thermal management temperature boundary value is determined according to the computing power of the battery management system, so that when the computing power of the battery management system is higher, the change of the thermal management temperature boundary value is more refined, and when the computing power of the battery management system is lower, the change of the thermal management temperature boundary value is simpler, so that 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 of the state of charge and the thermal management temperature boundary value is determined, so that when the attribute information of the battery indicates that the quality of the battery is higher, the thermal management temperature boundary value at a low state of charge is higher, and when the attribute information of the battery indicates that the quality of the battery is lower, the thermal management temperature boundary value at a low state of charge is lower, so that refined thermal management according to the actual condition of the battery can improve the stability of battery operation.

[0013] In some embodiments, the target temperature boundary value includes a first temperature boundary value and a second temperature boundary value; 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 includes: determining the thermal management temperature boundary value corresponding to the current state of charge of the battery in the thermal management temperature boundary value of the full state of charge range as the first temperature boundary value; determining the difference between the first temperature boundary value and the preset temperature offset value as the second temperature boundary value; and thermally managing 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 embodiment of the present application, the first temperature boundary value and the second temperature boundary value of each state of charge are determined by the thermal management temperature boundary value of the full state of charge range, and the second temperature boundary value is the difference between the first temperature boundary value and the preset temperature offset value. In this way, each state of charge has a first temperature boundary value and a second temperature boundary value with a difference of the temperature offset value, 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, thereby improving the effectiveness of thermal battery management.

[0014] In some embodiments, the battery is thermally managed according to the current temperature, the first temperature boundary value and the second temperature boundary value of the battery, including: when the current temperature is greater than or equal to the first temperature boundary value, the battery is thermally managed in a first thermal management mode; when the current temperature is greater than or equal to the second temperature boundary value and less than the first temperature boundary value, the battery is thermally managed in a second thermal management mode; wherein the temperature drop rate of the battery in the first thermal management mode is greater than the temperature drop rate of the battery in the second thermal management mode. In the technical solution of the embodiment 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 mode with a relatively high temperature drop rate is adopted, so that the battery can be rapidly cooled; 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 mode with a relatively low temperature drop rate is switched to, so that the battery can be cooled gently, thereby improving the pertinence of the thermal management of the battery, and thus improving the rationality of the thermal management of the battery.

[0015] In some embodiments, the battery is thermally managed according to the current temperature of the battery and the target temperature boundary value, including: when the battery is in a charging state, the charging mode of the battery is obtained; when the charging mode of the battery is a slow charging mode, the operation of the heat dissipation device of the battery is controlled according to the current temperature of the battery and the target temperature boundary value, and / or the charging rate of the battery is reduced; when the charging mode of the battery is a fast charging mode, the operation of the heat dissipation device of the battery is controlled according to the current temperature of the battery and the target temperature boundary value. In the technical solution of the embodiment of the present application, when the charging mode of the battery is a slow charging mode, a thermal management solution for reducing the charging rate of the battery can be considered, which is beneficial to reduce the cooling pressure of the heat dissipation device and improve the reliability of the battery during the charging process; when the charging mode of the battery is a fast charging mode, a thermal management solution for 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.

[0016] 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: obtaining a target temperature difference between the current temperature of the battery and the target temperature boundary value; determining the target operating power of the heat sink according to the target temperature difference and the corresponding relationship between the operating power of the heat sink of the battery and the temperature difference; and controlling the heat sink 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 sink is determined based on 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 sink 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 sink is also large, and when the target temperature difference is small, the target operating power of the heat sink is also small, thereby achieving accurate battery thermal management and reducing battery temperature fluctuations, thereby improving battery reliability.

[0017] In some embodiments, obtaining the current state of charge and current temperature of the battery includes: obtaining the state of charge of multiple cells in the battery and the temperatures of the multiple cells; determining the maximum value among the states of charge of the multiple cells as the current state of charge, and determining the maximum value among the temperatures of the multiple cells as the current temperature. In the technical solution of the embodiment of the present application, since the self-heating starting temperature decreases with the increase of the state of charge, the maximum value among the states of charge of the multiple cells is determined as the current state of charge, so that 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 cells, so that the battery is thermally managed according to the minimum temperature boundary value, which can improve the reliability of all cells in the battery; and the maximum value among the temperatures of the multiple cells is determined as the current temperature, so that the battery is thermally managed according to the maximum value among the temperatures of the multiple cells, which can improve the reliability of all 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 comprising: an acquisition module, used to acquire a thermal management temperature boundary value for a full state of charge range; wherein the thermal management temperature boundary value for the full state of charge range is determined based on the self-heating starting temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include a maximum state of charge in the full state of charge range; a determination module, used to determine a target temperature boundary value based on a current state of charge of the battery and the thermal management temperature boundary value for the full state of charge range; a thermal management module, used to perform thermal management on the battery based on 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, wherein the memory stores a computer program, and the processor implements the steps of any of the above methods when executing the computer program.

[0020] In a fourth aspect, the present application provides a vehicle, comprising a battery and the above-mentioned battery management system; the battery is connected to the battery management system.

[0021] In a fifth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of any of the above methods when the computer program is executed by a processor.

[0022] In a sixth aspect, the present application provides a computer program product, including a computer program, which implements the steps of any of the above methods when the computer program is executed by a processor. BRIEF 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 drawings required for use in the embodiments of the present application or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 A schematic diagram of the structure of an electric device provided in some embodiments;

[0025] Figure 2 A schematic flow chart of a thermal management method for a battery provided in the first embodiment;

[0026] Figure 3 A schematic flow chart of a thermal management method for a battery provided in a second embodiment;

[0027] Figure 4 A schematic flow chart of a thermal management method for a battery provided in a third embodiment;

[0028] Figure 5 A schematic flow chart of a thermal management method for a battery provided in a fourth embodiment;

[0029] Figure 6 A schematic flow chart of a thermal management method for a battery provided in a fifth embodiment;

[0030] Figure 7 A schematic flow chart of a battery thermal management method provided in a sixth embodiment;

[0031] Figure 8 A schematic flow chart of a thermal management method for a battery provided in a seventh embodiment;

[0032] Fig. 9 A schematic flow chart of a thermal management method for a battery provided in an eighth embodiment;

[0033] Fig.10 A schematic diagram of thermal management temperature boundary values ​​for the full state of charge range provided for the first embodiment;

[0034] Fig.11 A schematic diagram of thermal management temperature boundary values ​​for the full state of charge range provided for the second embodiment;

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

[0036] Fig.13 A schematic diagram of the structure of a thermal management device for a battery provided in some embodiments;

[0037] Fig.14 A schematic diagram of the structure of a battery management system provided in some embodiments. DETAILED DESCRIPTION

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

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians 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" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0040] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0041] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0042] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0043] The thermal management of the current vehicle battery management system (BMS) adopts the following scheme: based on a set fixed temperature threshold, when the battery temperature is higher than the fixed temperature threshold, the battery is thermally managed. Exemplarily, the thermal management of the battery may include controlling the start-up of a water cooling device.

[0044] However, the above-mentioned fixed temperature threshold is often set based on experience. The solution of battery thermal management based on the fixed temperature threshold and the current temperature of the battery will cause the problem of unreasonable battery temperature control solution. For example, when the fixed temperature threshold is set high, it is easy to cause the operating temperature of the battery to be high, affecting the reliability of the battery. For another example, when the fixed temperature threshold is set low, the battery temperature is low, which will not only reduce the charging capacity of the battery, but also in order to maintain the low temperature of the battery, the battery thermal management needs to be continuously performed, which increases the thermal management power consumption of the battery.

[0045] To alleviate the above problems, research has found that the safe operating temperature of a battery in a low 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 a fully charged state and performing thermal management of the battery according to the thermal management temperature boundary value of the fully charged state, the battery can be operated below the thermal management temperature boundary value as much as possible, thereby improving the reliability of the battery. In addition, by flexibly performing thermal management of the battery according to the thermal management temperature boundary value of the fully charged state, the thermal management temperature boundary value of the battery changes dynamically with the change of the battery's state of charge. Therefore, it is possible to avoid the situation where the battery is always operating at a low temperature, thereby improving the battery's charging capacity.

[0046] Based on the above considerations, the present application provides a thermal management method for a battery, which obtains a thermal management temperature boundary value for a full state of charge range; wherein the thermal management temperature boundary value for the full state of charge range is determined based on the self-heating starting temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include a maximum state of charge in the full state of charge range; a target temperature boundary value is determined based on the current state of charge of the battery and the thermal management temperature boundary value for the full state of charge range; and the battery is thermally managed based on the current temperature of the battery and the target temperature boundary value.

[0047] In this way, thermal management of the battery can be flexibly performed according to the current state of charge of the battery, the current temperature and the precisely set thermal management temperature boundary value of the full state of charge 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 value of the full state of charge range, thereby improving the rationality of battery thermal management; the thermal management temperature boundary value of the full state of charge range is not static, but varies, then when the thermal management temperature boundary value of the full state of charge range is high, the allowable operating temperature of the battery is higher, avoiding the situation in the related technology where a relatively fixed temperature threshold is used to perform thermal management on the battery, causing the battery to always operate at a relatively fixed temperature, thereby improving the charging efficiency of the battery, which is beneficial to improving the fast charging performance of the battery Energy; and, the battery is thermally managed according to the thermal management temperature boundary value of the full charge state range, so as to avoid the battery temperature exceeding the thermal management temperature boundary value under the corresponding charge state 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 value of the full charge state range is determined based on the self-heating starting temperatures of at least two reference charge states, so that the battery temperature will not exceed the self-heating starting temperature of the battery as much as possible, thereby improving the safety of battery use, and there is no need to measure the self-heating starting temperatures of all charge states under the full charge range, which reduces the time for establishing the thermal management temperature boundary value of the full charge state range, thereby improving the efficiency of establishing the thermal management temperature boundary value of the full charge state range.

[0048] The thermal management method of the battery disclosed in the embodiment of the present application can be applied to a battery management system or other control devices (for the sake of ease of description, the application to the battery management system is used as an example below), and the battery management system can be included in an electrical device. Exemplarily, the electrical device may include, but is not limited to, one of the following: a vehicle, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, and the like. In some embodiments, the vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, and the like. In some embodiments, the electric toy may include a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, or an electric airplane toy, and the like. In some embodiments, the spacecraft may include an airplane, a rocket, a space shuttle, or a spacecraft, and the like.

[0049] Figure 1 A schematic diagram of a structure of an electric device provided in some embodiments, such as Figure 1As shown, a battery 11 is disposed inside the electric device 10, and the battery 11 can be disposed at the bottom, head, or tail of the electric device 10. The battery 11 can be used to power the electric device 10. For example, the battery 11 can be used as a driving power source for the electric device 10, replacing or partially replacing fuel or natural gas to provide driving power for the electric device 10. In some embodiments, the battery 11 can not only be used as a driving power source for the electric device 10, but also as an operating power source for the electric device 10. The electric device 10 may further include a battery management system 12, which is capable of detecting the temperature and state of charge of the battery 11. In some embodiments, the electric device 10 may further include a heat dissipation device 13, which is disposed near or around the battery 11. The battery management system 12 may control the start-up of the heat dissipation device 13 when the temperature of the battery 11 is higher than the temperature threshold, so as to cool the battery 11.

[0050] Figure 2 A schematic flow chart of a thermal management method for a battery provided in a first embodiment, the method is applied to a battery management system, and the method includes:

[0051] S201, obtaining thermal management temperature boundary values ​​in a full state of charge range.

[0052] The thermal management temperature boundary value for the full state of charge range in the embodiment of the present application is different from the temperature threshold in the related art. The existing temperature threshold is an empirical value, while the embodiment of the present application is a precise thermal management temperature boundary value for the full state of charge range, that is, the thermal management temperature boundary value that matches the battery's 0% state of charge to 100% state of charge range.

[0053] In some embodiments, the thermal management temperature boundary value of 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 value of the full state of charge range can be determined according to the thermal safety temperature boundary value of the battery. For example, the thermal management temperature boundary value of the full state of charge range can be the thermal safety temperature boundary value of the battery to improve the precision of the thermal management temperature boundary value of the full state of charge range. For another example, the thermal management temperature boundary value of the full state of charge range can be determined according to the thermal safety temperature boundary value of the battery under at least two states of charge to improve the convenience of obtaining the thermal management temperature boundary value of 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 a battery can operate safely includes the temperature at which the battery does not react when the battery is not charged or discharged. 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-heating starting temperature of the battery. In some embodiments, the thermal safety temperature boundary value of the battery may be the self-heating starting temperature of the battery. In other embodiments, the thermal safety temperature boundary value of the battery may be the smaller value of the self-heating starting temperature of the battery and the critical temperature at which the electrolyte decomposes.

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

[0056] In another embodiment, the thermal management temperature boundary value of the full state of charge range is determined based on the self-heating starting temperature of the battery and the critical temperature of the decomposition reaction of the battery electrolyte. Exemplarily, the thermal management temperature boundary value of the full state of charge range is determined based on the critical temperature of the decomposition reaction of the battery electrolyte and the self-heating starting temperatures of at least two reference states of charge of the battery.

[0057] In some other embodiments, the thermal management temperature boundary value of the full state of charge range is determined based on the self-heating 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 operates reliably. Exemplarily, the maximum operating temperature of the battery can be included in the attribute information of the battery. Exemplarily, the thermal management temperature boundary value of the full state of charge range is determined based on the maximum operating temperature of the battery and the self-heating start temperature of at least two reference states of charge of the battery.

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

[0059] Exemplarily, the change of the thermal management temperature boundary value in the full state of charge range is different due to different health states of the battery. Exemplarily, the change of the thermal management temperature boundary value in the full state of charge range is different due to different computing capabilities of the battery management system. Exemplarily, the change of the thermal management temperature boundary value in the full state of charge range is different due to different attribute information of the battery.

[0060] For example, the thermal management temperature boundary values ​​for the full state of charge range obtained may include: the thermal management temperature boundary values ​​for the full state of charge range that match the current health state. For example, the thermal management temperature boundary values ​​for the full state of charge range obtained may include: the thermal management temperature boundary values ​​for the full state of charge range that match the computing capability of the battery management system. For example, the thermal management temperature boundary values ​​for the full state of charge range obtained may include: the thermal management temperature boundary values ​​for the full state of charge range that match the attribute information of the battery. For example, the thermal management temperature boundary values ​​for the full state of charge range obtained may include: the thermal management temperature boundary values ​​for the full state of charge range that match the current health state and the computing capability 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 battery, the cycle life of the battery, the health status 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 value of each state of charge within the full state of charge range is less than or equal to the self-heating starting temperature of each state of charge. In some embodiments, the thermal management temperature boundary value of each state of charge within the full state of charge range tends to decrease as the state of charge increases.

[0063] In some embodiments, the self-heating starting temperature of the battery can be obtained by measuring the self-heating starting temperature of a reference battery, wherein the reference battery has the same characteristics as the battery.

[0064] In some embodiments, the reference battery may be a test battery. In some embodiments, the reference battery may be a battery cell. In some embodiments, the reference battery and the battery having the same characteristics may include: the reference battery and the battery cell having the same characteristics. In some embodiments, the reference battery and the battery having the same characteristics may include at least one of the following being the same: the same battery properties, the same shape and size, the same manufacturer, the same production equipment, etc.

[0065] In some embodiments, the self-heating start temperatures of different charge states are measured using different reference batteries. This can avoid the situation where the measurement of the self-heating start temperature of one charge state will trigger a self-heating reaction in the reference battery, and the reference battery will continue to be used to measure the self-heating start temperature of the next charge state, resulting in an inaccurate self-heating start temperature measured next time.

[0066] Exemplarily, the thermal management temperature boundary values ​​of the full state of charge range can be stored in the form of a mapping table. For example, the battery management system stores multiple states of charge with set intervals within the full state of charge range and the thermal management temperature boundary values ​​of the multiple states of charge. For example, the set interval can be 0.01, 0.005 or 0.02, etc. Also exemplarily, the thermal management temperature boundary values ​​of the full state of charge range can be stored in the form of a curve. Also exemplarily, the thermal management temperature boundary values ​​of 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 value of the full state of charge range is determined based on the self-heating start temperature of at least two reference states of charge. In some embodiments, the thermal management temperature boundary value of each state of charge in the full state of charge range is the self-heating start temperature of the battery in each state of charge in the full state of charge range. In other embodiments, the thermal management temperature boundary value of each state of charge in the full state of charge range is obtained based on the analysis of the self-heating start temperature of at least two reference states of charge.

[0068] In some embodiments, among at least two reference states of charge arranged from large to small or from small to large, the intervals between two adjacent states of charge are the same or different. Exemplarily, the interval between two adjacent states of charge can be flexibly determined according to the accuracy requirements and / or the computational convenience requirements of the thermal management temperature boundary value of the full state of charge range. For example, when the accuracy requirement is higher, the interval between two adjacent states of charge is smaller, and conversely, when the accuracy requirement is lower, the interval between two adjacent states of charge is larger. For another example, when the computational convenience requirement is higher, the interval between two adjacent states of charge is larger, and conversely, when the computational convenience requirement is lower, the interval between two adjacent states of charge is smaller.

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

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

[0071] In some embodiments, the battery may include a combination of cells connected in series, in parallel, or in series-parallel connection. For example, the battery may be a battery pack, a battery module, a battery device, a battery assembly, or a cell. In some embodiments, the battery may include a plurality of battery cells.

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

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

[0074] In some embodiments, a thermal management temperature boundary value of a current state of charge in a full state of charge range may be determined as a target temperature boundary value.

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

[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, thermal management of the battery may include controlling the battery to cool down. Exemplarily, controlling the battery to cool down may include at least one of the following: controlling the operation of a heat dissipation device of the battery, controlling the battery to reduce the charge rate, and controlling the battery to reduce the discharge rate. Exemplarily, the heat dissipation device may include a liquid cooling device and / or an air cooling device.

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

[0079] In some embodiments, the battery may also be thermally managed according to whether the battery is in a charging state or a discharging state. Exemplarily, when the battery is in a charging state, thermal management of the battery may include at least one of the following: controlling the operation of a heat dissipation device of the battery, and controlling the reduction of the charging rate of the battery. Exemplarily, when the battery is in a discharging state, thermal management of the battery may include at least one of the following: controlling the operation of a heat dissipation device of the battery, and controlling the reduction of the discharge rate of the battery.

[0080] Exemplarily, thermally managing the battery includes controlling the operation of a heat dissipation device of the battery. Also exemplary, thermally managing the battery includes controlling the operation of a heat dissipation device of the battery and controlling to reduce a charge rate of the battery.

[0081] In some embodiments, the battery may be thermally managed 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, the battery thermal management includes controlling the battery to cool down. For another example, when the current temperature is less than the target temperature boundary value, the battery thermal management includes not controlling the battery temperature.

[0082] In the technical solution of the embodiment of the present application, the thermal management of the battery can be flexibly performed according to the current state of charge of the battery, the current temperature and the accurately set thermal management temperature boundary value of the full state of charge 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 value of the full state of charge range, thereby improving the rationality of the thermal management of the battery; the thermal management temperature boundary value of the full state of charge range is not static, but varies, then when the thermal management temperature boundary value of the full state of charge range is high, the allowable operating temperature of the battery is higher, avoiding the use of a relatively fixed temperature threshold for thermal management of the battery in the related art, resulting in the battery always operating at a relatively fixed temperature, thereby improving the charging efficiency of the battery, which is beneficial to improving the battery Fast charging performance; and, the battery is thermally managed according to the thermal management temperature boundary value of the full charge state range, so as to avoid the battery temperature exceeding the thermal management temperature boundary value under the corresponding charge state 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 value of the full charge state range is determined based on the self-heating starting temperatures of at least two reference charge states, so that the battery temperature will not exceed the self-heating starting temperature of the battery as much as possible, thereby improving the safety of battery use, and there is no need to measure the self-heating starting temperatures of all charge states under the full charge range, which reduces the time for establishing the thermal management temperature boundary value of the full charge state range, thereby improving the efficiency of establishing the thermal management temperature boundary value of the full charge state range.

[0083] In some embodiments, the thermal management temperature boundary value of the full state of charge range is determined based on the self-heating starting temperature of the reference battery at different states of charge. In this way, the battery can be thermally managed through the thermal management temperature boundary value of the full state of charge range, which can avoid the self-heating reaction of the battery as much as possible and improve the reliability of the battery. Therefore, the allowable operating temperature of the battery at a low state of charge is greater than the allowable operating temperature of the battery at a high state of charge, avoiding the situation where the battery always works at a low temperature, thereby improving the fast charging performance of the battery to a certain extent.

[0084] In some embodiments, some limiting conditions for thermal management temperature boundary values ​​over the full state of charge range may be described as follows:

[0085] In some embodiments, the thermal management temperature boundary value of the full state of charge range is determined based on the self-heating start temperatures of at least two reference states of charge of the battery; wherein the at least two reference states of charge include the maximum state of charge in the full state of charge range.

[0086] In some embodiments, the thermal management temperature boundary values ​​of the state of charge within the range of 0 to the minimum reference state of charge are all the self-heating starting temperatures of the minimum reference state of charge. In some embodiments, the self-heating starting 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 value of the state of charge between two adjacent reference states of charge is determined based on the self-heating starting temperatures of the two adjacent reference states of charge.

[0087] In some embodiments, the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge is determined based on the rate of change of the self-heating starting temperatures of the two adjacent reference states of charge. In other embodiments, the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge is the self-heating starting temperature of the larger reference state of charge of the two adjacent reference states of charge.

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

[0089] Figure 3 A schematic flow chart of a thermal management method for a battery provided in the second embodiment, as shown in FIG. Figure 3 As shown, the method is applied to a battery management system. Figure 3 Example and Figure 2 The difference between the embodiments is that S201 includes S2011 and S2012:

[0090] S2011. Obtain self-heating starting temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include a maximum state of charge in a full state of charge range.

[0091] In some embodiments, at least two reference states of charge may be pre-set values, and the interval between at least two reference states of charge is a preset interval. Exemplarily, at least two reference states of charge may include: 60%, 70%, 80%, 90% and 100%. Again exemplary, at least two reference states of charge may include: 70%, 80%, 90% and 100%. Again exemplary, at least two reference states of charge may include: 90% and 100%.

[0092] In some embodiments, the minimum self-exothermic starting temperature of at least two reference states of charge is greater than or equal to the maximum operating temperature of the battery, and the second minimum self-exothermic starting temperature of at least two reference states 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. Again exemplarily, the maximum operating temperature of the battery may be the maximum operating temperature in the battery attribute information.

[0093] In some embodiments, the self-heating starting temperatures of at least two reference states of charge can be determined according to a preset interval between the reference states of charge and the maximum operating temperature of the battery. For example, in some embodiments, the self-heating starting temperatures of at least two reference states of charge are determined as follows: determine the preset interval between the reference states of charge (take 10% as an example), determine the self-heating starting temperature when the state of charge of the battery is 100%, determine whether the self-heating starting temperature is greater than or equal to the maximum operating temperature of the battery, if not, determine the self-heating starting temperature when the state of charge of the battery is 90%, determine whether the self-heating starting temperature is greater than or equal to the maximum operating temperature of the battery, if yes, use 90% and 100% as at least two reference states of charge, if not, determine the self-heating starting temperature when the state of charge of the battery is 80%, and so on, so as to obtain at least two reference states of charge.

[0094] S2012: Determine a thermal management temperature boundary value for the entire state of charge range based on the self-heating start temperatures of at least two reference states of charge.

[0095] In some embodiments, an interpolation method may be used to determine a thermal management temperature boundary value for the entire state of charge range based on the self-heating start temperatures of at least two reference states of charge.

[0096] In the technical solution of the embodiment of the present application, the thermal management temperature boundary value of the full charge state range is determined based on the self-heating starting temperatures of at least two reference charge states. There is no need to measure the self-heating starting temperatures of all charge states in the full charge range, which reduces the time for establishing the thermal management temperature boundary value of the full charge state range, thereby improving the efficiency of establishing the thermal management temperature boundary value of the full charge state range.

[0097] In some embodiments, the thermal management temperature boundary values ​​of the charge states within the range of 0 to the minimum reference charge state are determined as the self-heating starting temperature of the minimum reference charge state; the self-heating starting temperatures of at least two reference charge states are determined as the thermal management temperature boundary values ​​of at least two reference charge states; and the thermal management temperature boundary value of the charge state between two adjacent reference charge states is determined based on the self-heating starting temperatures of two adjacent reference charge states.

[0098] For example, determining the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge based on the self-heating starting temperatures of two adjacent reference states of charge may include: determining the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge by using an interpolation method based on the self-heating starting temperatures of at least two reference states of charge.

[0099] In the technical solution of the embodiment of the present application, the thermal management temperature boundary values ​​of the charge states within the range of 0 to the minimum reference charge state are all determined as the self-heating starting temperature of the minimum reference charge state, thereby improving the convenience of determining the thermal management temperature boundary values ​​of each charge state within this interval; the self-heating starting temperatures of at least two reference charge states are determined as the thermal management temperature boundary values ​​of at least two reference charge states, thereby ensuring the accuracy of the thermal management temperature boundary values ​​of at least two reference charge states; based on the self-heating starting temperatures of two adjacent reference charge states, the thermal management temperature boundary value of the charge state between two adjacent reference charge states is determined, thereby avoiding the self-heating starting temperatures of other reference charge states other than the two adjacent reference charge states from interfering with the determination of the thermal management temperature boundary value of the charge state between the two adjacent reference charge states, thereby improving the accuracy of the determined thermal management temperature boundary value of the charge state between the two adjacent reference charge states.

[0100] In some embodiments, a thermal management temperature boundary value of the state of charge between two adjacent reference states of charge is determined based on the self-heating starting temperatures of the two adjacent reference states of charge, including: determining the thermal management temperature boundary value of the state of charge between two adjacent reference states of charge based on the rate of change of the self-heating starting temperatures of the two adjacent reference states of charge.

[0101] In the technical solution of the embodiment of the present application, the gradual change process of the self-heating characteristics of the battery under different states of charge is taken into account, so that 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 thermal management temperature boundary value of the state of charge between two adjacent reference states of charge.

[0102] In other embodiments, a thermal management temperature boundary value of the state of charge between two adjacent reference states of charge is determined based on the self-heating starting temperatures of the two adjacent reference states of charge, including: determining the self-heating starting temperature of the larger reference state of charge among the 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.

[0103] In the technical solution of the embodiment of the present application, the self-heating starting temperature of the larger reference state of charge between two adjacent reference states of charge is determined as the thermal management temperature boundary value of the charge state between the two adjacent reference states of charge, thereby improving the convenience of determining the thermal management temperature boundary value of the charge state between the two adjacent reference states of charge.

[0104] Figure 4 A schematic flow chart of a battery thermal management method provided in a third embodiment, the method is applied to a battery management system, and the method is compared with Figure 2 The difference between the embodiments is that S201 includes S2013 and S2014:

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

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

[0107] In some embodiments, the current health state of the battery can be determined based on at least one of the following: battery life, battery operating time, battery charge times, battery range, etc. For example, the current health state of the battery can be determined based on the battery operating time, and the battery operating time can be the difference between the current time and the time when the vehicle was purchased.

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

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

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

[0111] Exemplarily, different health states have different correspondences between full power state ranges and thermal management temperature boundary values. In some embodiments, if a health state of multiple health states is the same as the current health state, the correspondence between the full power state range and the thermal management temperature boundary value of the health state is determined as the thermal management temperature boundary value of the full power state range. In other embodiments, multiple health states are arranged in order from large to small. If multiple health states are different from the current health state, a target health state that is smaller than the current health state for the first time is obtained, and the correspondence between the full power state range corresponding to the target health state and the thermal management temperature boundary value is determined as the thermal management temperature boundary value of the full power state range.

[0112] In some embodiments, Figure 4 The solution of the embodiment can be used with Figure 3 The scheme of the embodiment is combined, for example, obtaining the self-heating starting temperatures of at least two reference charge states of each health state of the battery in multiple health states; determining the thermal management temperature boundary value of the full charge state range of each health state based on the self-heating starting temperatures of at least two reference charge states 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, the thermal management temperature boundary value of the full charge state range that matches the current health state of the battery is determined from the mapping relationship of multiple health states, and the thermal management of the battery can also match the current health state of the battery, avoiding the battery's health state deteriorating after long-term use, but still using the thermal management temperature boundary value of the full charge state range with a higher health state to thermally manage the battery, resulting in battery overheating. Therefore, the embodiment of the present application can improve the reliability of the battery.

[0114] Figure 5 A schematic flow chart of a battery thermal management method provided in a fourth embodiment, the method is applied to a battery management system. Figure 2 The difference between the embodiments is that S201 includes S2015 to S2017:

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

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

[0117] Please refer to the above for the description of the battery's attribute information, which will not be repeated here.

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

[0119] In some embodiments, different mapping types may include different change relationships. In some embodiments, determining the mapping type of the state of charge and the thermal management temperature boundary value may include: determining the mapping type of the state of charge and the thermal management temperature boundary value from a plurality of corresponding types. Exemplarily, the plurality of corresponding types may include: a corresponding type of a continuous thermal management temperature boundary value, a corresponding type of a multi-stage thermal management temperature boundary value. Exemplarily, the corresponding type of the multi-stage thermal management temperature boundary value may include at least one of the following: a corresponding type of a five-stage thermal management temperature boundary value, a corresponding type of a four-stage thermal management temperature boundary value, a corresponding type of a three-stage thermal management temperature boundary value, a corresponding type of a two-stage thermal management temperature boundary value, and a corresponding type of a 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 degree of fineness of the change of the thermal management temperature boundary value in the corresponding type of the continuous thermal management temperature boundary value is greater than the degree of fineness of the change of the thermal management temperature boundary value in the corresponding type of the multi-stage thermal management temperature boundary value. In some embodiments, in the corresponding type of the multi-stage thermal management temperature boundary value, the higher the number of stages, the finer the change of the thermal management temperature boundary value.

[0121] In some embodiments, when the change of the thermal management temperature boundary value is more refined, the thermal management temperature boundary value in the low charge state is higher. Exemplarily, the low charge state includes 0%. For example, the low charge state includes 0% to 10%. For another example, the low charge state includes 0% to 30%. For another example, the low charge state includes 0% to 50%, etc., which is not limited in the embodiments of the present application.

[0122] For example, the multiple corresponding types can be the following Figures 10 to 12 shown.

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

[0124] In some embodiments, thermal management temperature boundary values ​​for the full state of charge range match the mapping type.

[0125] In some embodiments, Figure 5 The embodiments can be used with Figure 4 In combination with the embodiments, for example, the mapping relationship of each health status has multiple mapping types.

[0126] In the technical solution of the embodiment of the present application, the mapping type of the state of charge and the thermal management temperature boundary value is determined according to the computing power of the battery management system, so that when the computing power of the battery management system is higher, the change of the thermal management temperature boundary value is finer, and when the computing power of the battery management system is lower, the change of the thermal management temperature boundary value is simpler, so that the battery management system can operate reasonably under different computing powers, thereby improving the rationality of battery thermal management; according to the attribute information of the battery, the mapping type of the state of charge and the thermal management temperature boundary value is determined, so that when the attribute information of the battery indicates that the quality of the battery is higher, the thermal management temperature boundary value at a low charge state is higher, and when the attribute information of the battery indicates that the quality of the battery is lower, the thermal management temperature boundary value at a low charge state is lower. In this way, refined thermal management can be performed according to the actual condition of the battery, which can improve the stability of battery operation.

[0127] Figure 6 A schematic flow chart of a battery thermal management method provided in a fifth embodiment, the method is applied to a battery management system, in which the target temperature boundary value includes a first temperature boundary value and a second temperature boundary value. Figure 2 The difference between the embodiments is that S202 includes S2021 to S2022, and S203 includes S2031:

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

[0129] For example, the thermal management temperature boundary values ​​of the entire state of charge range include the thermal management temperature boundary value of the 0% state of charge, the thermal management temperature boundary value of the 1% state of charge, and up to the thermal management temperature boundary value of the 100% state of charge. When the current state of charge is 11%, the thermal management temperature boundary value of the 11% state of charge is determined as the first temperature boundary value. When the current state of charge changes to 12%, the thermal management temperature boundary value of the 12% state of charge is determined as the first temperature boundary value. In this way, each time the current state of charge changes, the first temperature boundary value can be determined based on the changed state of charge.

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

[0131] For example, each time a first temperature boundary value is determined, a second temperature boundary value is determined based on the first temperature boundary value.

[0132] In some embodiments, the preset temperature offset value may be a fixed offset value. In other embodiments, the preset temperature offset value may be a variable offset value. Exemplarily, the preset temperature offset value may be determined according to the state of charge of the battery. For example, according to the mapping relationship between the preset temperature offset value and the state of charge, the corresponding temperature offset value is determined. For example, when the state of charge is less than 10% or greater than 90%, the temperature offset value is a 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 a 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 charge state are determined by the thermal management temperature boundary value of the full charge state range, and the second temperature boundary value is the difference between the first temperature boundary value and the preset temperature offset value. In this way, each charge state has a first temperature boundary value and a second temperature boundary value whose difference is the temperature offset value, which is beneficial for performing multiple levels of thermal management of the battery according to the current temperature of the battery, the first temperature boundary value and the second temperature boundary value, thereby improving the effectiveness of thermal battery management.

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

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

[0137] In some embodiments, the battery is thermally managed based on the current temperature of the battery, a first temperature boundary value, and a second temperature boundary value, including: when the current temperature is greater than or equal to the second temperature boundary value and less than the first temperature boundary value, the battery is thermally managed 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.

[0138] In some embodiments, when the current temperature is less than the second temperature boundary value, thermally managing 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, thermally managing the battery includes thermally managing the battery in a third thermal management mode, and the temperature drop rate of the battery in the third thermal management mode is less than the temperature drop rate of the battery in the second thermal management mode.

[0139] In some embodiments, the second thermal management method may include at least one of the following: controlling the heat dissipation device of the battery to operate with a second operating power, controlling the battery's charge rate to be reduced by a second charge rate, and controlling the battery's discharge rate to be reduced by a second discharge rate. The first operating power is greater than the second operating power. The first charge rate is greater than the second charge rate. The first discharge rate is greater than the second discharge rate.

[0140] In some embodiments, the first control mode and the second control mode have the same control type. 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. For another example, the first control mode is to control the heat dissipation device of the battery to operate at a first operating power, and to control the battery's charging rate 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 to control the battery's charging rate to be reduced by a second charging rate.

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

[0142] In the technical solution of the embodiment 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 a first thermal management method with a larger temperature drop rate is adopted 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 low, and the second thermal management method with a smaller temperature drop rate is switched to achieve mild cooling of the battery, thereby improving the targeted thermal management of the battery and thereby improving the rationality of the thermal management of the battery.

[0143] Figure 7 A schematic flow chart of a battery thermal management method provided in a sixth embodiment, the method is applied to a battery management system, and the method is compared with Figure 2 The difference between the embodiments is that S203 includes S2032 to S2034.

[0144] S2032: When the battery is in a charging state, obtain a 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 super charging mode corresponding to charging level 3, or a DC fast charging mode. The embodiments of the present application do not limit the specific type of the fast charging mode. In some embodiments, wireless charging can be a slow charging mode or a fast charging mode depending on the size of the charging power.

[0146] S2033: When the battery charging mode 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, according to the current temperature and the target temperature boundary value, thermal management of the battery includes controlling the operation of a heat dissipation device of the battery. Exemplarily, when the charging mode of the battery is a slow charging mode, according to the current temperature and the target temperature boundary value, thermal management of the battery includes reducing the charging rate of the battery. Exemplarily, when the charging mode of the battery is a slow charging mode, according to the current temperature and the target temperature boundary value, thermal management of the battery includes controlling the operation of a heat dissipation device of the battery and reducing the charging rate of the battery.

[0148] S2034: When the battery charging mode is the 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, the operating power of the heat dissipation device controlling the battery is a third operating power. When the charging mode of the battery is a fast charging mode, the operating power of the heat dissipation device controlling the battery is a fourth operating power. The magnitude relationship between the third operating power and the fourth operating power is determined based on 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 the fast charging process, in order to avoid the battery from overheating, the third operating power can be made less than the fourth operating power.

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

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

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

[0153] When the charging mode of the battery is a 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, thermal management of the battery includes controlling a heat dissipation device of the battery to operate using a second operating power, and / or controlling a charging rate of the battery to be reduced by a second charging rate. 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 the current temperature is greater than or equal to the first temperature boundary value, thermal management of the battery includes controlling a heat dissipation device of the battery to operate using a fifth operating power.

[0155] When the charging mode of the battery is the fast charging mode and the current temperature is greater than or equal to the second temperature boundary value and less than the first temperature boundary value, thermal management of the battery includes controlling the heat dissipation device of the battery to operate at a 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 a slow charging mode, it is possible to consider using a thermal management solution that reduces the charging rate of the battery, which is beneficial to reduce the cooling pressure of the heat sink and is beneficial to improving the reliability of the battery during the charging process; when the charging mode of the battery is a fast charging mode, consider the thermal management solution for the operation of the heat sink, 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 A schematic flow chart of a battery thermal management method provided in a seventh embodiment, wherein the method is applied to a battery management system. Figure 8 Example compared to Figure 2 The difference between the embodiments is that S203 includes S2035 to S2037.

[0158] S2035. Obtain a 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 a first temperature boundary value.

[0160] Illustratively, the target temperature difference may 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, a target temperature difference between the current temperature and the first temperature boundary value is obtained, 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, a target temperature difference between the current temperature and the first temperature boundary value is obtained. The preset temperature threshold is less than the first temperature boundary value. Exemplarily, the preset temperature threshold may 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 at the current state of charge, a target temperature difference between the current temperature and the first temperature boundary value is obtained. The most suitable operating temperature of the battery at 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 may be stored in the battery management system, and the most suitable operating temperature of the battery at the current state of charge is determined based on the 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 may be pre-stored in the battery management system.

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

[0167] In some embodiments, Figure 8 Embodiments may be used with Figure 6 For example, thermal management of the battery can be performed according to the current temperature of the battery and the target temperature boundary value by the following methods:

[0168] Obtain a target temperature difference between the current temperature and a 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, determining that the target temperature difference is greater than or equal to 0, and determining that the target operating power of the heat dissipation device is greater than or equal to the first operating power 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; 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, determine that the target temperature difference is less than 0, and determine 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 based on the target temperature difference and the correspondence between the operating power of the heat dissipation device of the battery and the temperature difference; thermal management of the battery includes: controlling the heat dissipation device to operate at a target operating power that is greater than or equal to the second operating power and less than the first operating power.

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

[0172] In some embodiments, Figure 8 Embodiments may be used with Figure 7 For example, thermal management of the battery can be performed according to the current temperature of the battery and the target temperature boundary value by the following methods:

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

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

[0175] When the charging mode of the battery is a slow charging mode, the target operating power of the heat dissipation device is determined 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 the 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 battery charging mode is the fast charging mode, the target operating power of the heat sink is determined according to the target temperature difference and the corresponding relationship between the operating power of the heat sink of the battery and the temperature difference, and the thermal management of the battery includes: controlling the heat sink of the battery to operate at the target operating power.

[0177] In the technical solution of the embodiment of the present application, the target operating power of the heat sink 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 sink 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 sink is also large, and when the target temperature difference is small, the target operating power of the heat sink is also small, thereby achieving precise battery thermal management, reducing battery temperature fluctuations, and improving battery reliability.

[0178] Fig. 9 A schematic flow chart of a battery thermal management method provided in an eighth embodiment, the method is applied to a battery management system. Figure 2 The difference between the embodiments is that, before S202, the method further includes:

[0179] S901 : Obtain the charge states of multiple cells in a battery and the temperatures of the multiple cells.

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

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

[0182] exist Fig. 9 In some other embodiments, an average value of the states of charge of the plurality of battery cells may be determined as the current state of charge, and an average value of the temperatures of the plurality of battery cells may be determined as the current temperature.

[0183] In the technical solution of the embodiment of the present application, since the self-heating starting temperature decreases with the increase of the state of charge, the maximum value among the states of charge of multiple battery cells is determined as the current state of charge, so that 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 multiple battery cells, so that the battery is thermally managed according to the minimum temperature boundary value, which can improve the reliability of all battery cells in the battery; and, the maximum value among the temperatures of multiple battery cells is determined as the current temperature, so that the battery is thermally managed according to the maximum value among the temperatures of multiple battery cells, which can improve the reliability of all battery cells in the battery.

[0184] In some embodiments, by determining the thermal management temperature boundary value of the battery at different states of charge, accurate dynamic battery temperature control based on the current state of charge and thermal management temperature boundary value of the battery can be achieved, and the thermal management strategy of the battery management system can be optimized, which is conducive to the implementation of intelligent water cooling control strategy. Through multi-level / segmented temperature adjustment, it is ensured that the battery is used within the thermal management temperature boundary value range in the full state of charge usage interval, reducing the risk of thermal runaway of the battery. By accurately setting the thermal management temperature boundary value of the full state of charge, the battery can be used at a low state of charge. The temperature can be increased, the fast charging capability can be improved, and the thermal management energy consumption can be reduced.

[0185] In some embodiments, a thermal management strategy for a battery management system to dynamically control a water cooling system based on a state of charge thermal management temperature boundary value is provided, and the self-heating starting 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 a full state of charge. The adiabatic calorimeter is used to safely measure the heat and heat release rate released during the storage and handling of chemical substances. The self-heating starting temperature refers to the temperature at which the self-heating reaction in the material starts during the heat treatment process. Self-heating refers to the spontaneous exothermic reaction of a material under specific conditions.

[0186] In some embodiments, a thermal management temperature boundary value used by a battery management system for battery thermal management is determined based on self-heating start temperatures obtained at different states of charge.

[0187] In some embodiments, the thermal management temperature boundary value of the full state of charge range is a thermal management temperature boundary value that varies 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-heating starting temperature of different charge states. In addition, by setting thermal management temperature boundary values ​​of multiple stages, the thermal management temperature boundary values ​​of each stage are consistent, so that a multi-level / segmented thermal management strategy can be implemented.

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

[0190] In some embodiments, by accurately setting the thermal management temperature boundary value at full charge, the thermal management strategy of the battery management system is optimized, an intelligent water cooling control strategy is implemented, and a multi-level / segmented thermal management strategy is implemented, so that the battery is used as much as possible below the thermal management temperature boundary value during the full charge usage range.

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

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

[0193] In some embodiments, the self-heating starting temperature of the battery at different states of charge is tested by an adiabatic calorimeter, which is the reliable use boundary temperature of the battery at a specific state of charge, thereby obtaining the thermal management temperature boundary value of the battery at a full charge state.

[0194] In some embodiments, the thermal management temperature boundary value of the battery in the fully charged state is input into the water cooling control system of the battery management system, and the battery is controlled to operate below the thermal management temperature boundary value as much as possible, so that the battery does not produce self-heating reaction as much as possible, thereby improving the reliability of the battery.

[0195] In some embodiments, the self-heating starting temperature of the battery at different states of charge is measured by an adiabatic calorimeter, that is, the self-heating starting temperature of the reference state of charge. The thermal management temperature boundary value of the full charge state is determined according to the self-heating starting temperature of the reference state of charge. Based on the thermal management temperature boundary values ​​of different states of charge in the full charge state, the thermal management system of the battery management system makes the battery temperature as low as possible from the thermal management temperature boundary value of the state of charge. According to the thermal management temperature boundary value of the battery, the battery temperature is monitored in real time to achieve dynamic adjustment of the battery temperature control under different state of charge conditions, realize multi-level / segmented temperature regulation, and improve the thermal management reliability of the battery management system.

[0196] In some embodiments, the adiabatic calorimeter can provide a (nearly) adiabatic environment, place the battery in the calorimetric chamber of the instrument, and perform step heating on the battery through the "Heat-Wait-Seek" mode to simulate the thermal runaway process of the battery when there is no heat exchange between the battery and the environment, so as to record the temperature change of the battery in an adiabatic environment. For example, the battery is suspended in the calorimetric chamber (or placed on a bracket), and the temperature-controlled thermocouple of the adiabatic calorimeter is firmly fixed at the center of the large surface of the battery surface. After the test starts, the battery is in an adiabatic environment in the calorimetric chamber of the adiabatic calorimeter, with no heat exchange with the surrounding environment. The adiabatic calorimeter thermally triggers the battery under test through a "step temperature rise" method. At each temperature step, when the battery and ambient temperatures are fully balanced and stable, the battery's self-heating rate (SHR) 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 test continues to the next temperature step until the SHR is greater than the predetermined value, that is, a self-heating reaction begins to occur inside the battery. The starting temperature when the SHR is greater than the predetermined value is recorded, that is, the self-heating starting temperature.

[0197] In some embodiments, an adiabatic calorimeter test is performed on the battery to obtain the self-heating start temperature of the battery at 0% to 100% state of charge, thereby obtaining the safe temperature usage boundary of the full state of charge. In other embodiments, an adiabatic calorimeter test is performed on the battery to obtain the self-heating start temperature of at least two reference states of charge, and the thermal management temperature boundary value of the full state of charge range is determined based on the self-heating start temperature of at least two reference states of charge.

[0198] The thermal management temperature boundary values ​​corresponding to the battery at different states of charge are input into the thermal management system of the battery management system. Based on the thermal management temperature boundary values, continuous graded adjustment of the battery temperature at full charge state is achieved, thereby achieving accurate and dynamic adjustment of thermal management.

[0199] Fig.10 A schematic diagram of thermal management temperature boundary values ​​for the full state of charge range provided by the first embodiment, as shown in FIG. Fig.10 As shown, the horizontal axis represents the state of charge, and the vertical axis represents the thermal management temperature boundary value (in °C). The thermal management temperature boundary value of the 0% to 60% state of charge is the self-heating starting temperature of the 60% state of charge, and the thermal management temperature boundary values ​​of 70%, 80%, 90%, and 100% are the self-heating starting temperatures of 70%, 80%, 90%, and 100%, respectively. The thermal management temperature boundary value of the state of charge in the (60%, 70%) interval is determined according to the change rate of the self-heating starting temperature of the 60% and 70% state of charge, the thermal management temperature boundary value of the (70%, 80%) interval is determined according to the change rate of the self-heating starting temperature of the 70% and 80% state of charge, the thermal management temperature boundary value of the (80%, 90%) interval is determined according to the change rate of the self-heating starting temperature of the 80% and 90% state of charge, and the thermal management temperature boundary value of the (90%, 100%) interval is determined according to the change rate of the self-heating starting temperature of the 90% and 100% state of charge.

[0200] Fig.11 A schematic diagram of thermal management temperature boundary values ​​for the full state of charge range provided for the second embodiment, as shown in FIG. Fig.11 As shown, the horizontal axis represents the state of charge, and the vertical axis represents the thermal management temperature boundary value (in °C). The thermal management temperature boundary value of the state of charge in the interval [0,70%] is the 70% state of charge self-heating starting temperature, the thermal management temperature boundary value of the state of charge in the interval (70%,80%] is the 80% state of charge self-heating starting temperature, the thermal management temperature boundary value of the state of charge in the interval (80%,90%] is the 90% state of charge self-heating starting temperature, and the thermal management temperature boundary value of the state of charge in the interval (90%,100%] is the 100% state of charge self-heating starting temperature.

[0201] In this way, by storing the self-heating starting temperatures of 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 ​​of the entire state of charge range (i.e., the 4-stage thermal management temperature boundary values). The battery management system can implement 4-stage battery thermal management based on the 4-stage thermal management temperature boundary values.

[0202] Fig.12 A schematic diagram of thermal management temperature boundary values ​​for the full state of charge range provided for the third embodiment, as shown in FIG. Fig.12 As shown, the horizontal axis represents the state of charge, and the vertical axis represents the thermal management temperature boundary value (in °C). The thermal management temperature boundary value of the state of charge in the [0,90%] interval is the 90% state of charge self-heating starting temperature, and the thermal management temperature boundary value of the state of charge in the (90%,100%] interval is the 100% state of charge self-heating starting temperature.

[0203] In this way, by storing the self-heating starting temperatures of 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 entire state of charge range (i.e., the 2-stage thermal management temperature boundary values). The battery management system can implement 2-stage battery thermal management based on the 2-stage thermal management temperature boundary values.

[0204] Based on the same inventive concept, the embodiment of the present application also provides a battery thermal management device for implementing the battery thermal management method involved above. The implementation solution provided by the device to solve the problem is similar to the implementation solution recorded in the above method, so the specific limitations in the embodiments of one or more battery thermal management devices provided below can refer to the limitations of the battery thermal management method above, and will not be repeated here.

[0205] In an exemplary embodiment, Fig.13 A schematic diagram of the structure of a thermal management device for a battery provided in some embodiments, such as Fig.13 As shown, the thermal management device 1300 of the battery includes:

[0206] An acquisition module 1301 is used to acquire a thermal management temperature boundary value for a full state of charge range; wherein the thermal management temperature boundary value for the full state of charge range is determined based on the self-heating starting temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include a maximum state of charge in the full state of charge range; a determination module 1302 is used to determine a target temperature boundary value based on a current state of charge of the battery and the thermal management temperature boundary value for the full state of charge range; a thermal management module 1303 is used to perform thermal management on the battery based on the current temperature of the battery and the target temperature boundary value.

[0207] In some embodiments, the acquisition module 1301 is also used to: obtain the self-heating starting 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; and determine the thermal management temperature boundary value of the full state of charge range based on the self-heating starting temperatures of at least two reference states of charge.

[0208] In some embodiments, the acquisition module 1301 is also used to: determine the thermal management temperature boundary values ​​of the charge state within the range of 0 to the minimum reference charge state as the self-heating starting temperature of the minimum reference charge state; determine the self-heating starting temperatures of at least two reference charge states as the thermal management temperature boundary values ​​of at least two reference charge states; and determine the thermal management temperature boundary value of the charge state between two adjacent reference charge states based on the self-heating starting temperatures of two adjacent reference charge states.

[0209] In some embodiments, the acquisition module 1301 is further used to determine a thermal management temperature boundary value of the state of charge between two adjacent reference states of charge according to a change rate of the self-heating start temperature of two adjacent reference states of charge.

[0210] In some embodiments, the acquisition module 1301 is further used to determine the self-heating starting temperature of the larger reference state of charge of 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.

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

[0212] In some embodiments, the acquisition module 1301 is also used to: obtain the computing power of the battery management system and / or the attribute information of the battery; determine the mapping type of the state of charge and the thermal management temperature boundary value based on the computing power of the battery management system and / or the attribute information of the battery; and obtain the thermal management temperature boundary value of the entire state of charge range based on 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 determination module 1302 is used to: determine the thermal management temperature boundary value corresponding to the current state of charge of the battery in the thermal management temperature boundary value of the full state of charge range as the first temperature boundary value; determine the difference between the first temperature boundary value and the preset temperature offset value as the second temperature boundary value; the thermal management module 1303 is also used 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 also used to: when the current temperature is greater than or equal to the first temperature boundary value, thermally manage the battery in a first thermal management mode; when the current temperature is greater than or equal to the second temperature boundary value and less than the first temperature boundary value, thermally manage the battery in a second thermal management mode; wherein the temperature drop rate of the battery in the first thermal management mode is greater than the temperature drop rate of the battery in the second thermal management mode.

[0215] In some embodiments, the thermal management module 1303 is also used 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 battery's heat dissipation device according to the current temperature of the battery and the target temperature boundary value, and / or reduce the battery's charging rate; when the battery's charging mode is a fast charging mode, control the operation of the battery's heat dissipation device 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 also used 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 correspondence 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 acquisition module 1301 is also used to: acquire the charge state of multiple battery cells in the battery and the temperature of multiple battery cells; the determination module 1302 is also used to: determine the maximum value among the charge states of multiple battery cells as the current charge state, and determine the maximum value among the temperatures of multiple battery cells as the current temperature.

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

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

[0220] In an exemplary embodiment, Fig.14 A schematic diagram of the structure 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, referred to 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 to exchange information between the processor and an external device. The communication interface of the battery management system is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a battery thermal management method is implemented.

[0221] Those skilled in the art will understand that Fig.14 The structure shown in the figure is only a block diagram of a partial structure related to the scheme of the present application, and does not constitute a limitation on the battery management system to which the scheme 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 certain components, or have a different arrangement of components.

[0222] For example, the battery management system includes a memory and a processor, the memory stores a computer program, and the processor implements the steps of the method of any of the above embodiments when executing the computer program.

[0223] For example, in an exemplary embodiment, the processor is used to execute a computer program to implement: obtaining a thermal management temperature boundary value for a full state of charge range; determining a target temperature boundary value based on a current state of charge of the battery and the thermal management temperature boundary value for a full state of charge range; and thermally managing the battery based on the current temperature of the battery and the target temperature boundary value.

[0224] In some embodiments, a vehicle is also provided, the vehicle includes a battery and the above-mentioned battery management system; the battery is connected to the battery management system. In some embodiments, the vehicle may also include a heat sink, the heat sink is arranged on the surface of the battery, and the heat sink is connected to the battery management system.

[0225] In some embodiments, a computer-readable storage medium is provided, and when a 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 a thermal management temperature boundary value for a full state of charge range; determining a target temperature boundary value based on a current state of charge of the battery and the thermal management temperature boundary value for the full state of charge range; and thermally managing the battery based on 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, which implements the following steps when executed by a processor: obtaining a thermal management temperature boundary value for a full state of charge range; determining a target temperature boundary value based on a current state of charge of the battery and the thermal management temperature boundary value for the full state of charge range; and thermally managing the battery based on the current temperature of the battery and the target temperature boundary value.

[0229] A person skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing related 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-mentioned 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, data processing logic based on quantum computing, 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 a non-volatile memory and a volatile memory. 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 Storage, Optical Disc, Compact Disc Read-Only Memory (CD-ROM), Tape, Floppy Disk, Flash Memory, Optical Storage, 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. Volatile memory includes an 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).

[0232] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, 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, they should be considered to be within the scope of this application.

[0233] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A battery thermal management method, characterized in that: The method comprises: Acquire a thermal management temperature boundary value of a full state of charge range; wherein the thermal management temperature boundary value of the full state of charge range is determined according to self-heating starting temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include a maximum state of charge in the full state of charge range; Determining a target temperature boundary value according to a current state of charge of the battery and a thermal management temperature boundary value of the full state of charge range; Thermal management is performed on the battery according to the current temperature of the battery and the target temperature boundary value.

2. The method according to claim 1, characterized in that The step of obtaining the thermal management temperature boundary value in the full state of charge range includes: Obtaining self-heating starting temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include a maximum state of charge in the full state of charge range; A thermal management temperature boundary value of the full state of charge range is determined according to the self-heating starting temperatures of the at least two reference states of charge.

3. The method according to claim 2, characterized in that The step of determining the thermal management temperature boundary value of the full state of charge range according to the self-heating starting temperatures of the at least two reference states of charge includes: Determine the thermal management temperature boundary values ​​of the state of charge within the range of 0 to the minimum reference state of charge as the self-heating starting temperature of the minimum reference state of charge; Determining the self-heating starting temperatures of the at least two reference states of charge as thermal management temperature boundary values ​​of the at least two reference states of charge; A thermal management temperature boundary value of the state of charge between the two adjacent reference states of charge is determined according to the self-heating starting temperatures of the two adjacent reference states of charge.

4. The method according to claim 3, characterized in that: The step of determining a thermal management temperature boundary value of the state of charge between the two adjacent reference states of charge according to the self-heating starting temperatures of the two adjacent reference states of charge comprises: Determine the thermal management temperature boundary value of the state of charge between the two adjacent reference states of charge according to the change rate of the self-heating starting temperature of the two adjacent reference states of charge; or, The self-heating starting temperature of the larger reference state of charge of the two adjacent reference states of charge is determined as the thermal management temperature boundary value of the state of charge between the two adjacent reference states of charge.

5. The method according to claim 1, characterized in that The step of obtaining the thermal management temperature boundary value in the full state of charge range includes: Obtaining the current health status of the battery; From the mapping relationships of the multiple health states obtained, determine the thermal management temperature boundary value of the full charge state range that matches the current health state; wherein the mapping relationship of each health state includes: the corresponding relationship between the full charge state range and the thermal management temperature boundary value in each health state.

6. The method according to claim 1, characterized in that The step of obtaining the thermal management temperature boundary value in the full state of charge range includes: Obtaining the computing capability of the battery management system and / or the property information of the battery; Determining a mapping type between a state of charge and a thermal management temperature boundary value according to a computing capability of the battery management system and / or attribute information of the battery; According to the mapping type, a thermal management temperature boundary value of the full state of charge range is obtained.

7. The method according to any one of claims 1 to 6, characterized in that: The target temperature boundary value includes a first temperature boundary value and a second temperature boundary value; and 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 includes: Determining, among the thermal management temperature boundary values ​​in the full state of charge range, a thermal management temperature boundary value corresponding to the current state of charge of the battery as the first temperature boundary value; Determine the difference between the first temperature boundary value and a preset temperature offset value as the second temperature boundary value; The thermally managing the battery according to the current temperature of the battery and the target temperature boundary value includes: thermally managing 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 The thermal management of 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, thermally managing the battery in a first thermal management manner; When the current temperature is greater than or equal to a second temperature boundary value and less than the first temperature boundary value, thermally managing the battery in a second thermal management manner; Wherein, the temperature drop rate of the battery in the first thermal management mode is greater than the temperature drop rate of the battery in the second thermal management mode.

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

10. The method according to any one of claims 1 to 6, characterized in that: The thermal management of the battery according to the current temperature of the battery and the target temperature boundary value includes: Obtaining a target temperature difference between the current temperature of the battery and the target temperature boundary value; Determining a target operating power of the heat dissipation device according to the target temperature difference and a corresponding relationship between the operating power of the heat dissipation device of the battery and the temperature difference; The heat dissipation device is controlled 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 comprises: Acquiring the state of charge of multiple cells in the battery and the temperature of the multiple cells; A maximum value among the states of charge of the plurality of battery cells is determined as the current state of charge, and a maximum value among the temperatures of the plurality of battery cells is determined as the current temperature.

12. A thermal management device for a battery, characterized in that: The thermal management device of the battery comprises: an acquisition module, configured to acquire a thermal management temperature boundary value of a full state of charge range; wherein the thermal management temperature boundary value of the full state of charge range is determined according to self-heating starting temperatures of at least two reference states of charge of the battery; the at least two reference states of charge include a maximum state of charge in the full state of charge range; A determination module, configured to determine a target temperature boundary value according to a current state of charge of the battery and a thermal management temperature boundary value of the full state of charge range; The thermal management module is used to perform thermal management on the battery according to the current temperature of the battery and the target temperature boundary value.

13. A battery management system, comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 11 are implemented.

14. A vehicle, characterized in that: The vehicle comprises a battery and the battery management system of claim 13; the battery is connected to the battery management system.

15. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 11 are implemented.

16. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 11 are implemented.

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