Temperature control method, device and equipment for power battery, storage medium and vehicle

Abstract

The invention discloses a temperature control method, device and equipment of a power battery, a storage medium and a vehicle, and is applied to the technical field of power battery temperature control, and the temperature control method of the power battery comprises the steps that a first controller of a battery management system receives an awakening instruction sent by a second controller under the condition that the first controller is in a dormant state; wherein the wake-up instruction carries the minimum value of the battery cell temperature, and the wake-up instruction is generated by the second controller under the condition that the minimum value of the battery cell temperature is smaller than or equal to the current wake-up temperature; according to the minimum value of the battery cell temperature, the current wake-up temperature, and the current residual electric quantity and the unit energy consumption temperature rise of the power battery, estimating the target residual electric quantity and the target battery cell temperature of the heated power battery; and performing heating control on the power battery according to the target residual electric quantity and the target battery cell temperature. According to the scheme, the situation that the discharging power of the power battery is limited due to low temperature after the vehicle is dormant and restarted is avoided, and normal use of the vehicle is guaranteed.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power battery temperature control, and particularly relates to a power battery temperature control method, device, equipment, storage medium and vehicle. BACKGROUND

[0002] With the increasingly serious global energy crisis and environmental pollution, developing new energy vehicles has become the main direction of the transformation of the world automobile industry. As one of the core components of new energy vehicles, the performance of power batteries directly determines the vehicle's range, safety and service life.

[0003] The discharge power of the power battery is not only affected by the remaining available power of the battery, but also by the temperature. When the temperature of the power battery is low, the discharge power of the power battery will be limited. For a hybrid vehicle, the limited discharge power may cause the vehicle to be unable to start the engine. For a pure electric vehicle, the limited discharge power will also affect the normal use of the vehicle. In the related technology, when the vehicle is in a dormant state, the vehicle cannot obtain the relevant information of the power battery, and the temperature of the power battery will gradually decrease. When the vehicle starts again, the problem of limited discharge power caused by low temperature of the power battery is likely to occur. SUMMARY

[0004] Embodiments of the application provide a power battery temperature control method, device, equipment, storage medium and vehicle, thereby at least to some extent avoiding the problem of limited discharge power caused by low temperature of the power battery when the vehicle is dormant and starts again, and ensuring the normal use of the vehicle.

[0005] Other characteristics and advantages of the application will become apparent from the following detailed description, or will be learned by practice of the application.

[0006] According to a first aspect of the embodiments of the application, a power battery temperature control method is provided, applied to a first controller of a battery management system, the battery management system further comprising a second controller; the power battery temperature control method comprises: In the case that the first controller is in a dormant state, receiving a wake-up instruction sent by the second controller; wherein the wake-up instruction carries a minimum value of a cell temperature, and the wake-up instruction is generated by the second controller in the case that the minimum value of the cell temperature is less than or equal to a current wake-up temperature; According to the minimum value of the cell temperature, the current wake-up temperature, the current remaining power of the power battery and the unit energy consumption temperature rise, estimating a target remaining power and a target cell temperature of the power battery after heating; According to the target remaining power and the target cell temperature, performing heating control on the power battery.

[0007] In some embodiments, the target remaining power and the target cell temperature of the power battery after heating are estimated according to the minimum value of the cell temperature, the current wake-up temperature, the current remaining power of the power battery, and the unit energy consumption temperature rise, including: determining a heat preservation rate of the power battery corresponding to the minimum value of the cell temperature; determining a temperature reduction amount of the power battery during the sleep period according to the heat preservation rate and the sleep interval duration; estimating the target remaining power and the target cell temperature of the power battery after heating according to the temperature reduction amount, the current wake-up temperature, the current remaining power, and the unit energy consumption temperature rise.

[0008] In some embodiments, the target remaining power and the target cell temperature of the power battery after heating are estimated according to the temperature reduction amount, the current wake-up temperature, the current remaining power, and the unit energy consumption temperature rise, including: estimating the target remaining power and / or the next wake-up temperature of the first controller of the power battery after heating according to the temperature reduction amount, the current wake-up temperature, the current remaining power, and the unit energy consumption temperature rise; estimating the target cell temperature according to the target remaining power or the next wake-up temperature.

[0009] In some embodiments, the target remaining power and / or the next wake-up temperature of the first controller of the power battery after heating are estimated according to the temperature reduction amount, the current wake-up temperature, the current remaining power, and the unit energy consumption temperature rise, including: obtaining a first correspondence relationship between the remaining power, the wake-up temperature, and the starting power of the engine; determining a second correspondence relationship between the target remaining power and the next wake-up temperature of the power battery after heating in the case of the target starting power according to the target starting power and the first correspondence relationship; obtaining a third correspondence relationship between the target remaining power and the next wake-up temperature in the case of the temperature reduction amount, the current wake-up temperature, the current remaining power, and the unit energy consumption temperature rise; estimating the target remaining power and / or the next wake-up temperature of the first controller of the power battery after heating according to the second correspondence relationship and the third correspondence relationship.

[0010] In some embodiments, the third correspondence relationship between the target remaining power and the next wake-up temperature in the case of the temperature reduction amount, the current wake-up temperature, the current remaining power, and the unit energy consumption temperature rise is obtained, including: obtaining a fourth correspondence relationship between the target remaining power and the target cell temperature in the case of the current wake-up temperature, the current remaining power, and the unit energy consumption temperature rise; obtaining a fifth correspondence relationship between the next wake-up temperature and the target cell temperature in the case of the temperature reduction amount; According to the fourth correspondence relationship and the fifth correspondence relationship, a third correspondence relationship between the target residual power and the next wake-up temperature is determined.

[0011] In some embodiments, the target battery cell temperature is estimated according to the target residual power or the next wake-up temperature, including: According to the target residual power and the current residual power, a power change amount is determined. According to the power change amount and the unit energy consumption temperature rise, an amount of temperature rise of the power battery after heating is estimated. The sum of the current wake-up temperature and the amount of temperature rise is taken as the target battery cell temperature.

[0012] In some embodiments, the target battery cell temperature is estimated according to the target residual power or the next wake-up temperature, including: The sum of the next wake-up temperature and the amount of temperature drop is taken as the target battery cell temperature.

[0013] In some embodiments, the temperature control method of the power battery further includes: Before entering the sleep state, a current wake-up temperature is determined according to the current residual power and the target starting power of the engine. The current wake-up temperature is sent to the second controller.

[0014] According to a second aspect of the embodiments of the present application, a temperature control method of a power battery is provided, applied to a second controller of a battery management system, the battery management system further including a first controller, and the temperature control method of the power battery includes: In the case that the first controller is in a sleep state, the battery cell temperatures of each battery cell of the power battery are acquired. In the case that the minimum value of the battery cell temperatures is less than or equal to the current wake-up temperature, a wake-up instruction is sent to the main controller, wherein the minimum value of the battery cell temperatures is carried in the wake-up instruction, so that the first controller estimates a target residual power and a target battery cell temperature of the power battery after heating according to the minimum value of the battery cell temperatures, the current wake-up temperature, the current residual power of the power battery and the unit energy consumption temperature rise, and controls the power battery according to the target residual power and the target battery cell temperature.

[0015] According to a third aspect of the embodiments of the present application, a temperature control device of a power battery is provided, applied to a first controller of a battery management system, the battery management system further including a second controller, and the temperature control device of the power battery includes: A wake-up instruction receiving module is configured to receive a wake-up instruction sent by the second controller in the case that the first controller is in a sleep state, wherein the minimum value of the battery cell temperatures is carried in the wake-up instruction, and the wake-up instruction is generated by the second controller in the case that the minimum value of the battery cell temperatures is less than or equal to the current wake-up temperature. The heating parameter estimation module is configured to estimate a target remaining power and a target cell temperature of the power battery after heating according to the minimum cell temperature, the current wake-up temperature, the current remaining power of the power battery, and a unit energy consumption temperature rise. The battery heating control module is configured to perform heating control on the power battery according to the target remaining power and the target cell temperature.

[0016] According to a fourth aspect of the embodiments of the present application, a temperature control device of a power battery is provided, which is applied to a second controller of a battery management system, the battery management system further comprising a first controller, and the temperature control device of the power battery comprises: The cell temperature acquisition module is configured to acquire cell temperatures of each cell of the power battery when the first controller is in a sleep state. The wake-up instruction sending module is configured to send a wake-up instruction to the main controller when the minimum cell temperature is less than or equal to the current wake-up temperature, wherein the minimum cell temperature is carried in the wake-up instruction, so that the first controller estimates a target remaining power and a target cell temperature of the power battery after heating according to the minimum cell temperature, the current wake-up temperature, the current remaining power of the power battery, and a unit energy consumption temperature rise, and performs heating control on the power battery according to the target remaining power and the target cell temperature.

[0017] According to a fifth aspect of the embodiments of the present application, a temperature control device of a power battery is provided, which comprises a processor and a memory, the memory stores computer program instructions capable of being executed by the processor, and the processor implements the steps of the method of any one of the first aspect and the second aspect when executing the computer program instructions.

[0018] According to a sixth aspect of the embodiments of the present application, a computer readable storage medium is provided, which stores computer program instructions, and the computer program instructions are executed by a processor to cause the processor to implement the steps of the method of any one of the first aspect and the second aspect.

[0019] According to a seventh aspect of the embodiments of the present application, a computer program product is provided, which comprises a computer program, and the computer program is executed by a processor to cause the processor to implement the steps of the method of any one of the first aspect and the second aspect.

[0020] According to an eighth aspect of the embodiments of the present application, a vehicle is provided, which comprises the temperature control device of the power battery of the fifth aspect and a power battery, and the temperature control device of the power battery comprises a first controller and a second controller of a battery management system, and the power supply of the first controller is different from the power supply of the second controller.

[0021] In the present application, after the first controller enters the sleep state, the second controller sends a wake-up instruction carrying the minimum value of the battery cell temperature to the first controller when detecting that the minimum value of the battery cell temperature is less than or equal to the current wake-up temperature. After receiving the wake-up instruction, the second controller is woken up, and according to the minimum value of the battery cell temperature, the current wake-up temperature, the current remaining power of the power battery, and the unit energy consumption temperature rise, the target remaining power and the target battery cell temperature of the power battery after heating are estimated, and then the heating control of the power battery is realized according to the target remaining power and the target battery cell temperature. After the vehicle is started again, the power battery will not be limited in discharge power due to low temperature, thereby ensuring the normal use of the vehicle.

[0022] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory, and are not limiting to the present application. BRIEF DESCRIPTION OF DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application. It is apparent that the accompanying drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings. In the drawings: Figure 1 An electrical architecture diagram of a vehicle according to some embodiments of the present application is shown; Figure 2 A flowchart of a temperature control method of a power battery according to some embodiments of the present application is shown; Figure 3 A flowchart of a temperature control method of a power battery according to some other embodiments of the present application is shown; Figure 4 A flowchart of a temperature control method of a power battery according to some other embodiments of the present application is shown; Figure 5 A block diagram of a temperature control device of a power battery according to some embodiments of the present application is shown; Figure 6 A block diagram of a temperature control device of a power battery according to some other embodiments of the present application is shown; Figure 7 A structural diagram of a temperature control device of a power battery according to some embodiments of the present application is shown. DETAILED DESCRIPTION

[0024] With reference to the drawings and the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative effort belong to the scope of the present application.

[0025] In addition, the described features, structures or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, many specific details are provided to give a full understanding of the embodiments of the present application. However, one of ordinary skill in the art will realize that the technical solutions of the present application can be practiced without one or more of the specific details, or other methods, components, devices, steps, etc. can be used. In other cases, well-known methods, devices, implementations or operations are not shown or described in detail to avoid obscuring the aspects of the present application.

[0026] The block diagram shown in the drawings is only a functional entity, which does not necessarily correspond to a physically independent entity. That is, the functional entity can be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0027] The flowchart shown in the drawings is only an exemplary illustration, which does not necessarily include all the contents and operations / steps, and does not necessarily be executed in the described order. For example, some operations / steps can be further decomposed, and some operations / steps can be combined or partially combined, so the actual execution order can be changed according to the actual situation.

[0028] It should be further noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the objects thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described.

[0029] In order for those skilled in the art to better understand the present application, first Figure 1 The application scenario of the temperature control method of the power battery involved in the present application is briefly described.

[0030] As Figure 1As shown, the vehicle includes a power battery 101, a battery management system 102, and a vehicle controller 103, wherein the battery management system 102 includes a first controller 1020 and a second controller 1021, the first controller 1020 can also be referred to as a master controller, and the second controller 1021 can also be referred to as a slave controller. The power supply of the first controller 1020 is different from that of the second controller 1021, generally, the first controller 1020 is powered by a storage battery, and the second controller 1021 is powered by the power battery. Before the vehicle is powered off and hibernates, the first controller 1020 can determine the current wake-up temperature of the first controller 1020 according to the current remaining power of the power battery 101 and the target power of the vehicle (for example, the minimum starting power of the engine), and send the current wake-up temperature to the second controller 1021. When the vehicle is powered off and hibernates, the vehicle controller 103 sends a hibernation instruction to the first controller 1020 and sends an instruction to enter a low-power mode to the second controller 1021. The first controller 1020 enters a hibernation state after receiving the hibernation instruction, and the second controller 1021 enters a low-power mode after receiving the low-power mode instruction, and periodically patrols the cell temperature of all cells of the power battery 101 in the low-power mode. If the minimum value of the cell temperature is less than or equal to the current wake-up temperature, the second controller 1021 sends a wake-up instruction carrying the minimum value of the cell temperature to the first controller 1020. The first controller 1020 is woken up after receiving the wake-up instruction, and estimates the target remaining power and the target cell temperature of the power battery 101 after heating according to the minimum value of the cell temperature, the current wake-up temperature, the current remaining power of the power battery 101, and the unit energy consumption temperature rise. Then, the first controller 1020 controls the heater, the water pump, the valve and other components according to the target remaining power and the target cell temperature, so as to realize the heating of the power battery 101, so that the remaining power of the power battery 101 after heating is the target remaining power, and the minimum value of the cell temperature rises to the target cell temperature. After the vehicle is started again, the power battery 101 will not be limited in discharge power due to low temperature, thereby ensuring the normal use of the vehicle.

[0031] Figure 2 A flowchart of a temperature control method of a power battery according to some embodiments of the present application is shown. As shown, the present application provides a temperature control method of a power battery. The method is applied to the first controller in the power battery as an example for illustration. The method can include the following steps: Figure 2 Figure 1 Step 201, in the case that the first controller is in a hibernation state, receiving a wake-up instruction sent by a second controller; wherein the wake-up instruction carries a minimum value of a cell temperature, and the wake-up instruction is generated by the second controller in the case that the minimum value of the cell temperature is less than or equal to a current wake-up temperature; ​​In step 202, the target remaining power and the target battery cell temperature of the power battery after heating are estimated according to the minimum value of the battery cell temperature, the current wake-up temperature, the current remaining power of the power battery and the unit energy consumption temperature rise. In step 203, the power battery is controlled to heat according to the target remaining power and the target battery cell temperature.

[0032] In step 201, when the vehicle is powered off and sleeps, the vehicle controller sends a sleep instruction to the first controller and sends an instruction to enter a low-power mode to the second controller. After receiving the sleep instruction, the first controller enters a sleep state. After receiving the low-power mode instruction, the second controller enters a low-power mode and periodically patrols the battery cell temperature of all battery cells in the low-power mode. If the minimum value of the battery cell temperature is less than or equal to the current wake-up temperature, a wake-up instruction carrying the minimum value of the battery cell temperature is generated and sent to the first controller to wake up the first controller.

[0033] In some embodiments, before step 201, the method can further include the steps of: before entering the sleep state, the first controller determines the current wake-up temperature according to the current remaining power and the target starting power of the engine; and sending the current wake-up temperature to the second controller.

[0034] Wherein, the current remaining power refers to the remaining power of the power battery at the current time, which can be the time when the first controller receives the sleep instruction or the time when the first controller enters the sleep state. The target starting power is the power required for the engine to start, which can be the minimum starting power of the engine.

[0035] In the implementation process, the power MAP table of the engine at low temperature can be obtained through experiments, as shown in Table 1 below: Table 1

[0036] Wherein, P11, P00 and P22 can be the minimum starting power of the engine, and the values of the three are equal. SOC1, SOC0 and SOC2 are all remaining powers, and increase in turn. T1 is the temperature corresponding to SOC1. At temperature T1, the power corresponding to the remaining power SOC1 is P11, which can exactly start the engine. T0 is the temperature corresponding to SOC0. At temperature T0, the power corresponding to the remaining power SOC0 is P00, which can exactly start the engine. T2 is the temperature corresponding to SOC2. At temperature T2, the power corresponding to the remaining power SOC2 is P22, which can exactly start the engine.

[0037] The first controller can determine the corresponding temperature according to the current remaining power and the minimum starting power of the engine by querying the power MAP table, and take the queried temperature as the current wake-up temperature, and then send the current wake-up temperature to the second controller.

[0038] The first controller can also fit the corresponding relationship among the power, the remaining power and the temperature according to the power MAP table. In some embodiments, the corresponding relationship among the power, the remaining power and the temperature can be expressed by the following formula: Formula one; Wherein T is the temperature, T∈(-35℃, -10℃], SOC is the remaining power, SOC < 60%, K is the adjustment coefficient, and P is the power.

[0039] The first controller can substitute the current remaining power and the minimum starting power of the engine into formula one to obtain the corresponding temperature, and take the obtained temperature as the current wake-up temperature, and then send the current wake-up temperature to the second controller.

[0040] By storing the temperature corresponding to the current remaining power and the target starting power of the engine as the wake-up temperature to the second controller before entering the sleep state by the first controller, the second controller can compare the cell temperature of the power battery with the wake-up temperature after the first controller enters the sleep state, and wake up the first controller when the cell temperature is too low, so as to heat the power battery, thereby avoiding that the temperature of the power battery is too low to limit the discharge power.

[0041] In step 202, the first controller can estimate the target remaining power and the target cell temperature of the power battery after heating according to the minimum value of the cell temperature, the current wake-up temperature, the current remaining power of the power battery and the unit energy consumption temperature rise.

[0042] Wherein, the unit energy consumption temperature rise refers to the temperature that can be heated to the power battery for each unit of remaining power consumed, which can be the temperature that can be heated to the power battery for each 1% of remaining power consumed. The target remaining power refers to the remaining power of the power battery after heating. It can be understood that heating the power battery will consume the energy in the battery, so the power of the battery will continue to decrease, and therefore the target remaining power is less than the current remaining power. The target cell temperature refers to the temperature of the power battery after heating, which can refer to the temperature of the cell after heating corresponding to the minimum value of the cell temperature. It can be understood that if the temperature of the cell corresponding to the minimum value of the cell temperature is heated to the target cell temperature, the temperature of other cells will be greater than or equal to the target cell temperature.

[0043] In some embodiments, the first controller can determine a temperature reduction amount of the power battery during the hibernation period according to the temperature reduction rate and the hibernation interval duration; and estimate the target remaining power and the target cell temperature of the power battery after heating according to the temperature reduction amount, the current wake-up temperature, the current remaining power and the unit energy consumption temperature rise.

[0044] The temperature reduction rate refers to the temperature reduction of the power battery per unit time, which can be the temperature reduction per hour. It can be understood that the temperature reduction rate is affected by temperature, specifically, the lower the temperature, the smaller the temperature reduction rate. In the embodiments of the present application, considering that the discharge power of the power battery is mainly affected by the minimum temperature, the temperature reduction rate corresponding to the minimum cell temperature is used to estimate the target remaining power and the target cell temperature, instead of using the temperature reduction rate corresponding to other higher cell temperatures, thereby improving the estimation accuracy of the target remaining power and the target cell temperature.

[0045] The hibernation interval duration refers to the duration of the interval between each hibernation and automatic wake-up of the first controller, which can be set according to actual conditions. In some embodiments, the hibernation interval duration can be greater than or equal to 6 hours, and of course the hibernation interval duration can also be set to be greater than or equal to 5 hours. It can be understood that the hibernation interval duration cannot be set too short. If the hibernation interval duration is too short, the first controller will be frequently woken up, which will in turn cause the power consumption of the power supply (battery) to increase dramatically, affecting the normal use of the vehicle.

[0046] After determining the temperature reduction rate corresponding to the minimum cell temperature, the first controller can multiply the temperature reduction rate by the hibernation interval duration to obtain the temperature reduction amount of the power battery during the hibernation period.

[0047] After determining the temperature reduction amount, the first controller can also estimate the target remaining power of the power battery after heating and / or the next wake-up temperature of the first controller according to the temperature reduction amount, the current wake-up temperature, the current remaining power and the unit energy consumption temperature rise; and estimate the target cell temperature according to the target remaining power or the next wake-up temperature.

[0048] In some embodiments, the first controller can obtain a first correspondence relationship between the remaining power, the wake-up temperature and the starting power of the engine; determine a second correspondence relationship between the target remaining power and the next wake-up temperature of the power battery after heating in the case of the target starting power according to the target starting power and the first correspondence relationship; obtain a third correspondence relationship between the target remaining power and the next wake-up temperature in the case of the temperature reduction amount, the current wake-up temperature, the current remaining power and the unit energy consumption temperature rise; and estimate the target remaining power of the power battery after heating and / or the next wake-up temperature of the first controller according to the second correspondence relationship and the third correspondence relationship.

[0049] Referring back to Formula One, Formula One is a corresponding relationship among power, residual capacity and temperature, and the temperature determined according to Formula One is the wake-up temperature, so the first corresponding relationship can be represented by Formula One. By substituting the target startup power (taking P0 as an example) into Formula One, a corresponding relationship between residual capacity and wake-up temperature can be obtained, in which, if the residual capacity is the current residual capacity SOC0, the wake-up temperature is the current wake-up temperature T0, and if the residual capacity is the target residual capacity SOC1, the wake-up temperature is the next wake-up temperature T1, so the second corresponding relationship that can be obtained according to the first corresponding relationship can be referred to as Formula Two as follows: Formula Two; wherein SOC1 is the target residual capacity, T1 is the next wake-up temperature, and P0 is the target startup power. In Formula Two, only the target residual capacity SOC1 and the next wake-up temperature T1 are unknown quantities, and other parameters (the target startup power P0 and the adjustment coefficient k) are known quantities.

[0050] It can be understood that the second corresponding relationship is fitted according to experimental data, and the third corresponding relationship is calculated according to physical principles.

[0051] In some embodiments, the first controller can obtain a fourth corresponding relationship between the target residual capacity and the target battery cell temperature under the condition of the current wake-up temperature, the current residual capacity and the unit energy consumption temperature rise, obtain a fifth corresponding relationship between the next wake-up temperature and the target battery cell temperature under the condition of the temperature drop, and determine the third corresponding relationship between the target residual capacity and the next wake-up temperature according to the fourth corresponding relationship and the fifth corresponding relationship.

[0052] It can be understood that the heating process will consume the power of the power battery, and according to this principle, the following Formula Three can be obtained: ΔSOC = SOC0 - SOC1 Formula Three; wherein ΔSOC is the residual capacity change, SOC0 is the current residual capacity, and SOC1 is the target residual capacity.

[0053] The temperature rise caused by the consumption of ΔSOC can be represented by the following Formula Four: ΔT = ΔSOC x λ = T2 - T0 Formula Four; wherein ΔT is the temperature rise, λ is the unit energy consumption temperature rise, T0 is the current wake-up temperature, and T2 is the target battery cell temperature.

[0054] By combining Formula Three and Formula Four, the fourth corresponding relationship between the target residual capacity and the target battery cell temperature can be obtained, which is represented by Formula Five as follows: Formula Five; Wherein, the current wake-up temperature T0, the current residual power SOC0 and the unit energy consumption temperature rise λ are known quantities, and the target residual power SOC1 and the target battery cell temperature T2 are unknown quantities.

[0055] The fifth corresponding relationship between the next wake-up temperature and the target battery cell temperature can be expressed by the following formula six: T1 = T2 - t x η Formula six Wherein, T1 is the next wake-up temperature, T2 is the target battery cell temperature, t is the hibernation interval length, η is the temperature retention rate, the hibernation interval length t and the temperature retention rate η are known quantities, and t x η is the temperature reduction amount.

[0056] By combining formula five and formula six, the third corresponding relationship between the target residual power and the next wake-up temperature can be obtained, which is expressed by the following formula seven: Formula seven In formula seven, only the target residual power SOC1 and the next wake-up temperature T1 are unknown quantities, and other parameters (the hibernation interval length t, the temperature retention rate η, the current wake-up temperature T0, the current residual power SOC0 and the unit energy consumption temperature rise λ) are known quantities.

[0057] By combining formula two and formula seven, the target residual power SOC1 and the next wake-up temperature T1 can be calculated. After the target residual power SOC1 and the next wake-up temperature T1 are calculated, two ways can be used to estimate the target battery cell temperature.

[0058] In some embodiments, the first controller can determine the power change amount according to the target residual power and the current residual power; estimate the temperature rise amount of the power battery after heating according to the power change amount and the unit energy consumption temperature rise; and take the sum of the current wake-up temperature and the temperature rise amount as the target battery cell temperature.

[0059] In the implementation process, the target residual power and the current residual power formula can be substituted into formula three to calculate the power change amount, then the power change amount and the unit energy consumption temperature rise can be substituted into formula four to calculate the temperature rise amount, and finally the sum of the current wake-up temperature and the temperature rise amount can be taken as the target battery cell temperature.

[0060] In some embodiments, the first controller can also take the sum of the next wake-up temperature and the temperature reduction amount as the target battery cell temperature.

[0061] In step 203, the first controller can perform heating control on the power battery according to the target residual power and the target battery cell temperature.

[0062] Specifically, the first controller can control the heater, the water pump, the valve and the like by using the target residual power and the target battery cell temperature after calculating the target residual power, the target battery cell temperature and the next wake-up temperature, so as to realize heating of the power battery, and send the next wake-up temperature to the second controller for the first controller to wake up next time when it is in sleep state.

[0063] The first controller of the battery management system receives the wake-up instruction sent by the second controller in the sleep state, wherein the wake-up instruction carries the minimum value of the battery cell temperature, and the wake-up instruction is generated by the second controller in the case that the minimum value of the battery cell temperature is less than or equal to the current wake-up temperature; the target residual power and the target battery cell temperature of the power battery after heating are estimated according to the minimum value of the battery cell temperature, the current wake-up temperature, the current residual power of the power battery and the unit energy consumption temperature rise; and the power battery is controlled to heat according to the target residual power and the target battery cell temperature. This scheme avoids that the discharge power of the power battery is limited due to low temperature after the vehicle is in sleep state and started again, and guarantees the normal use of the vehicle.

[0064] Figure 3 A flowchart of a temperature control method of a power battery according to another embodiment of the application is shown. As shown in Figure 3 Another temperature control method of a power battery is provided, and the method is applied to the first controller of a hybrid vehicle as an example for illustration, which can include the following steps: In step 301, the first controller determines the current wake-up temperature according to the current residual power and the target starting power of the engine before entering the sleep state, and sends the current wake-up temperature to the second controller; In step 302, the wake-up instruction sent by the second controller is received in the sleep state of the first controller, wherein the wake-up instruction carries the minimum value of the battery cell temperature, and the wake-up instruction is generated by the second controller in the case that the minimum value of the battery cell temperature is less than or equal to the current wake-up temperature; In step 303, the temperature reduction amount of the power battery during the sleep period is determined according to the heat preservation rate corresponding to the minimum value of the battery cell temperature and the sleep interval time length; In step 304, the target residual power and / or the next wake-up temperature of the first controller of the power battery after heating are estimated according to the temperature reduction amount, the current wake-up temperature, the current residual power and the unit energy consumption temperature rise; In step 305, the target battery cell temperature is estimated according to the target residual power or the next wake-up temperature; In step 306, the power battery is controlled to heat according to the target residual power and the target battery cell temperature, and the next wake-up temperature is sent to the second controller.

[0065] The embodiment of the present application can heat the power battery after the first controller enters the sleep state, effectively solves the problem that the hybrid vehicle cannot obtain battery information in the sleep state, and the discharge power is insufficient due to the low temperature of the power battery after the vehicle is powered on again, and the engine cannot be started, and can also avoid frequent heating of the battery, thereby saving the power of the battery.

[0066] Based on the same concept, the present application provides another temperature control method of a power battery, Figure 4 The flowchart of the temperature control method of the power battery according to still another embodiment of the present application is shown. The method is applied to the second controller in the hybrid vehicle as an example for description. The method can include the following steps: Figure 1 Step 401: In the case that the first controller is in the sleep state, the cell temperature of each cell of the power battery is obtained. Step 402: In the case that the minimum value of the cell temperature is less than or equal to the current wake-up temperature, a wake-up instruction is sent to the main controller, wherein the minimum value of the cell temperature is carried in the wake-up instruction, so that the first controller estimates the target remaining power and the target cell temperature of the power battery after heating according to the minimum value of the cell temperature, the current wake-up temperature, the current remaining power of the power battery and the unit energy consumption temperature rise, and controls the heating of the power battery according to the target remaining power and the target cell temperature.

[0067] It can be understood that the second controller can be connected with the power battery and directly powered by the power battery. The second controller can also be connected with the temperature sensor of each cell of the power battery to obtain the cell temperature of each cell from the temperature sensor in real time.

[0068] When the first controller does not enter the sleep state, the second controller can also obtain the cell temperature of each cell in real time and send the cell temperature to the first controller for temperature control of the power battery. When the first controller enters the sleep state, the second controller also enters the low-power mode. In the low-power mode, the second controller will only send the wake-up instruction carrying the minimum value of the cell temperature to the first controller to wake up the first controller to control the heating of the power battery in the case that the minimum value of the cell temperature is less than or equal to the current wake-up temperature.

[0069] For specific technical details of the first controller estimating the target remaining power and the target cell temperature of the power battery after heating according to the minimum value of the cell temperature, the current wake-up temperature, the current remaining power of the power battery and the unit energy consumption temperature rise, and controlling the heating of the power battery according to the target remaining power and the target cell temperature, reference can be made to the above-mentioned embodiments of the temperature control method of the power battery applied to the first controller of the present application, which will not be described here. ​

[0070] The application sets two controllers in the battery management system, when the first controller enters the sleep state, the second controller judges whether to wake up the first controller to control the heating of the power battery according to whether the battery cell temperature is too low, improves the temperature of the power battery, so that after the vehicle starts again, the power battery will not be limited by the discharge power due to the low temperature, thereby ensuring the normal use of the vehicle.

[0071] The device embodiment of the application is introduced below, which can be used to execute the temperature control method of the power battery in the above-mentioned embodiments of the application. For details not disclosed in the device embodiment of the application, please refer to the above-mentioned embodiments of the temperature control method of the power battery.

[0072] Figure 5 A block diagram of a temperature control device of a power battery according to some embodiments of the application is shown. As shown in Figure 5 The temperature control device of the power battery in the embodiments of the application is applied to the first controller of the battery management system, the battery management system further includes a second controller, and the temperature control device of the power battery can include: a wake-up instruction receiving module 501, a heating parameter estimation module 502, and a battery heating control module 503, wherein the wake-up instruction receiving module 501 can be used to receive a wake-up instruction sent by the second controller in the case that the first controller is in a sleep state; wherein the wake-up instruction carries a minimum value of the battery cell temperature, and the wake-up instruction is generated by the second controller in the case that the minimum value of the battery cell temperature is less than or equal to the current wake-up temperature; the heating parameter estimation module 502 can be used to estimate the target remaining capacity and the target battery cell temperature of the power battery after heating according to the minimum value of the battery cell temperature, the current wake-up temperature, the current remaining capacity of the power battery, and the unit energy consumption temperature rise; and the battery heating control module 503 can be used to control the heating of the power battery according to the target remaining capacity and the target battery cell temperature.

[0073] In some embodiments, based on the foregoing scheme, the heating parameter estimation module 502 can also be used to determine a temperature retention rate of the power battery corresponding to the minimum value of the battery cell temperature; determine a temperature reduction amount of the power battery during the sleep period according to the temperature retention rate and the sleep interval duration; and estimate the target remaining capacity and the target battery cell temperature of the power battery after heating according to the temperature reduction amount, the current wake-up temperature, the current remaining capacity, and the unit energy consumption temperature rise.

[0074] In some embodiments, based on the foregoing scheme, the heating parameter estimation module 502 can also be used to estimate the target remaining capacity and / or the next wake-up temperature of the first controller of the power battery after heating according to the temperature reduction amount, the current wake-up temperature, the current remaining capacity, and the unit energy consumption temperature rise; and estimate the target battery cell temperature according to the target remaining capacity or the next wake-up temperature.

[0075] In some embodiments, based on the foregoing scheme, the heating parameter estimation module 502 can also be configured to obtain a first correspondence between the remaining power, the wake-up temperature and the starting power of the engine; determine, according to the target starting power and the first correspondence, a second correspondence between the target remaining power of the power battery after heating and the next wake-up temperature under the target starting power; obtain a third correspondence between the target remaining power and the next wake-up temperature under the temperature reduction amount, the current wake-up temperature, the current remaining power and the unit energy consumption temperature rise; and estimate the target remaining power of the power battery after heating and / or the next wake-up temperature of the first controller according to the second correspondence and the third correspondence.

[0076] In some embodiments, based on the foregoing scheme, the heating parameter estimation module 502 can also be configured to obtain a fourth correspondence between the target remaining power and the target cell temperature under the current wake-up temperature, the current remaining power and the unit energy consumption temperature rise; obtain a fifth correspondence between the next wake-up temperature and the target cell temperature under the temperature reduction amount; and determine the third correspondence between the target remaining power and the next wake-up temperature according to the fourth correspondence and the fifth correspondence.

[0077] In some embodiments, based on the foregoing scheme, the heating parameter estimation module 502 can also be configured to determine the power change amount according to the target remaining power and the current remaining power; estimate the temperature rise amount of the power battery after heating according to the power change amount and the unit energy consumption temperature rise; and take the sum of the current wake-up temperature and the temperature rise amount as the target cell temperature.

[0078] In some embodiments, based on the foregoing scheme, the heating parameter estimation module 502 can also be configured to take the sum of the next wake-up temperature and the temperature reduction amount as the target cell temperature.

[0079] In some embodiments, based on the foregoing scheme, the temperature control device of the power battery further comprises a pre-sleep processing module (not shown in the figure), configured to determine the current wake-up temperature according to the current remaining power and the target starting power of the engine before entering the sleep state; and send the current wake-up temperature to the second controller.

[0080] Figure 6 A block diagram of a temperature control device of a power battery according to another embodiment of the present application is shown. As shown in FIG. 6, the temperature control device of the power battery comprises a first controller 601, a second controller 602, a power battery 603, a heating parameter estimation module 604 and a temperature control module 605. Figure 6As shown, the temperature control device of the power battery is applied to a second controller of a battery management system, the battery management system further includes a first controller, and the temperature control device of the power battery can include a battery cell temperature acquisition module 601 and a wake-up instruction sending module 602, wherein the battery cell temperature acquisition module 601 can be used to acquire the battery cell temperature of each battery cell of the power battery in the case that the first controller is in a sleep state; the wake-up instruction sending module 602 can be used to send a wake-up instruction to the main controller in the case that the minimum value of the battery cell temperature is less than or equal to the current wake-up temperature, wherein the minimum value of the battery cell temperature is carried in the wake-up instruction, so that the first controller estimates the target remaining power and the target battery cell temperature of the power battery after heating according to the minimum value of the battery cell temperature, the current wake-up temperature, the current remaining power of the power battery and the unit energy consumption temperature rise, and performs heating control on the power battery according to the target remaining power and the target battery cell temperature.

[0081] Based on the same inventive concept, the embodiment of the present application further provides a temperature control device of a power battery, which refers to Figure 7 , a structure schematic diagram of the temperature control device of the power battery in the embodiment of the present application is shown, the temperature control device of the power battery includes one or more memories 704, one or more processors 702, and at least one computer program (computer program instructions) stored in the memory 704 and executable on the processor 702, and the processor 702 executes the computer program to realize the method as described above.

[0082] In the above method, Figure 7 , a bus architecture (represented by a bus 700), the bus 700 can include any number of interconnected buses and bridges, and the bus 700 links various circuits including one or more processors represented by the processor 702 and the memory represented by the memory 704. The bus 700 can also link various other circuits such as peripheral devices, voltage stabilizers and power management circuits, which are well known in the art, and therefore, they will not be further described herein. The bus interface 705 provides an interface between the bus 700 and the receiver 701 and the transmitter 703. The receiver 701 and the transmitter 703 can be the same element, i.e. a transceiver, which provides a unit for communicating with various other devices on a transmission medium. The processor 702 is responsible for managing the bus 700 and general processing, while the memory 704 can be used to store data used by the processor 702 in performing operations.

[0083] Based on the same inventive concept, the embodiment of the present application provides a computer readable storage medium, the computer readable storage medium stores computer program instructions, and the computer program instructions are executed by a processor to make the processor realize the steps of the method as described above.

[0084] Based on the same inventive concept, the embodiment of the present application provides a computer program product comprising a computer program, which, when executed by a processor, causes the processor to implement the steps of the method as described above.

[0085] Based on the same inventive concept, the embodiment of the present application provides a vehicle. Referring back to Figure 1 , the vehicle comprises the temperature control device of the power battery and the power battery 101 as described above; wherein the temperature control device of the power battery comprises a first controller 1020 and a second controller 1021 of the battery management system, and the power supply of the first controller 1020 is different from the power supply of the second controller 1021.

[0086] In some embodiments, the power supply of the first controller 1020 is a power storage, and the power supply of the second controller 1021 is the power battery.

[0087] In some embodiments, the vehicle can further comprise a vehicle controller 103, configured to send a sleep instruction to the first controller 1020 and send an entering low-power mode instruction to the second controller 1021 in the case that the vehicle is powered off and sleeps, so that the first controller 1020 enters a sleep state after receiving the sleep instruction, and the second controller 1021 enters a low-power mode after receiving the low-power mode instruction.

[0088] The functions described herein can be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions can be stored on or transferred over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope and spirit of the disclosure and appended claims. For example, due to the nature of software, functions described above can be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions can also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations. Also, as technology evolves, the underlying functions can change, and it is within the scope of the disclosure to substitute new functions for old functions as those change.

[0089] In several embodiments provided in the present application, it should be understood that the disclosed technical contents can be implemented by other ways. Among them, the above-mentioned device embodiments are only schematic, for example, the division of the units can be a logical function division, and actual implementation can have another division way, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point, the coupling or direct coupling or communication connection between the displayed or discussed each other can be through some interface, indirect coupling or communication connection between units or modules, which can be electrical or other forms.

[0090] The units described as separate components may or may not be physically separate, and the components of the control device may or may not be physical units, i.e., may be located in one place, or may be distributed to multiple units. Part or all of the units can be selected as needed to achieve the purpose of the embodiment.

[0091] The integrated units, if implemented in the form of software functional units and sold or used as independent products, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application, essentially or in part, or all or part of the technical solutions, can be embodied in the form of a software product. The computer software product is stored in a storage medium, and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk, and various other media that can store computer program instructions.

[0092] The above only describes the embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the scope of the claims of the present application.

Claims

1. A temperature control method for a power battery, characterized in that, A first controller applied to a battery management system, the battery management system further comprising a second controller; the method comprises: In the case that the first controller is in a sleep state, receiving a wake-up instruction sent by the second controller; wherein the wake-up instruction carries a minimum value of a cell temperature, and the wake-up instruction is generated by the second controller in the case that the minimum value of the cell temperature is less than or equal to a current wake-up temperature; According to the minimum value of the cell temperature, the current wake-up temperature, the current remaining capacity of the power battery and the unit energy consumption temperature rise, estimating the target remaining capacity and the target cell temperature of the power battery after heating; According to the target remaining capacity and the target cell temperature, performing heating control on the power battery.

2. The temperature control method of a power battery according to claim 1, characterized in that, The method of estimating the target remaining capacity and the target cell temperature of the power battery after heating according to the minimum value of the cell temperature, the current wake-up temperature, the current remaining capacity of the power battery and the unit energy consumption temperature rise, comprises: Determining a temperature holding rate of the power battery corresponding to the minimum value of the cell temperature; According to the temperature holding rate and the sleep interval time length, determining a temperature reduction amount of the power battery during the sleep period; According to the temperature reduction amount, the current wake-up temperature, the current remaining capacity and the unit energy consumption temperature rise, estimating the target remaining capacity and the target cell temperature of the power battery after heating.

3. The temperature control method of a power battery according to claim 2, characterized in that, The method of estimating the target remaining capacity and the target cell temperature of the power battery after heating according to the temperature reduction amount, the current wake-up temperature, the current remaining capacity and the unit energy consumption temperature rise, comprises: According to the temperature reduction amount, the current wake-up temperature, the current remaining capacity and the unit energy consumption temperature rise, estimating the target remaining capacity and / or the next wake-up temperature of the first controller after heating of the power battery; According to the target remaining capacity or the next wake-up temperature, estimating the target cell temperature.

4. The temperature control method of a power battery according to claim 3, characterized in that, The method of estimating the target remaining capacity and / or the next wake-up temperature of the first controller after heating of the power battery according to the temperature reduction amount, the current wake-up temperature, the current remaining capacity and the unit energy consumption temperature rise, comprises: Obtaining a first corresponding relationship between the remaining capacity, the wake-up temperature and the starting power of the engine; According to the target starting power and the first corresponding relationship, determining a second corresponding relationship between the target remaining capacity and the next wake-up temperature of the power battery after heating in the case of the target starting power; Obtaining a third corresponding relationship between the target remaining capacity and the next wake-up temperature in the case of the temperature reduction amount, the current wake-up temperature, the current remaining capacity and the unit energy consumption temperature rise; According to the second corresponding relationship and the third corresponding relationship, estimating the target remaining capacity and / or the next wake-up temperature of the first controller after heating of the power battery.

5. The temperature control method of a power battery according to claim 4, characterized in that, The method of obtaining the third corresponding relationship between the target remaining capacity and the next wake-up temperature in the case of the temperature reduction amount, the current wake-up temperature, the current remaining capacity and the unit energy consumption temperature rise, comprises: obtaining a fourth correspondence relationship between the target remaining electric quantity and the target battery cell temperature in the case of the current wake-up temperature, the current remaining electric quantity, and the unit energy consumption temperature rise; obtaining a fifth correspondence relationship between the next wake-up temperature and the target battery cell temperature in the case of the temperature drop amount; determining a third correspondence relationship between the target remaining electric quantity and the next wake-up temperature according to the fourth correspondence relationship and the fifth correspondence relationship.

6. The temperature control method of a power battery according to claim 3, characterized in that, The target battery cell temperature is estimated according to the target remaining electric quantity or the next wake-up temperature, including: determining an electric quantity change amount according to the target remaining electric quantity and the current remaining electric quantity; estimating a temperature rise amount of the power battery after heating according to the electric quantity change amount and the unit energy consumption temperature rise; taking a sum of the current wake-up temperature and the temperature rise amount as the target battery cell temperature.

7. The temperature control method of a power battery according to claim 3, characterized in that, The target battery cell temperature is estimated according to the target remaining electric quantity or the next wake-up temperature, including: taking a sum of the next wake-up temperature and the temperature drop amount as the target battery cell temperature.

8. The temperature control method of a power battery according to claim 1, characterized in that, Further comprising: determining the current wake-up temperature according to the current remaining electric quantity and a target starting power of an engine before entering the sleep state; sending the current wake-up temperature to the second controller.

9. A method for temperature control of a power cell, characterized by A second controller applied to a battery management system, the battery management system further comprising a first controller, and the method comprises: obtaining battery cell temperatures of each battery cell of a power battery in the case that the first controller is in a sleep state; sending a wake-up instruction to the main controller in the case that a minimum value of the battery cell temperatures is less than or equal to a current wake-up temperature, wherein the wake-up instruction carries the minimum value of the battery cell temperatures, so that the first controller estimates a target remaining electric quantity and a target battery cell temperature of the power battery after heating according to the minimum value of the battery cell temperatures, the current wake-up temperature, a current remaining electric quantity of the power battery, and a unit energy consumption temperature rise, and performs heating control on the power battery according to the target remaining electric quantity and the target battery cell temperature.

10. A temperature control device for a power cell, characterized by A first controller applied to a battery management system, the battery management system further comprising a second controller, and the device comprises: a wake-up instruction receiving module configured to receive a wake-up instruction sent by the second controller in the case that the first controller is in a sleep state, wherein the wake-up instruction carries a minimum value of battery cell temperatures, and the wake-up instruction is generated by the second controller in the case that the minimum value of the battery cell temperatures is less than or equal to a current wake-up temperature; a heating parameter estimation module configured to estimate a target remaining electric quantity and a target battery cell temperature of the power battery after heating according to the minimum value of the battery cell temperatures, the current wake-up temperature, a current remaining electric quantity of the power battery, and a unit energy consumption temperature rise; a battery heating control module configured to perform heating control on the power battery according to the target remaining electric quantity and the target battery cell temperature.

11. A temperature control device for a power cell, characterized by A second controller applied to a battery management system, the battery management system further comprising a first controller, and the device comprises: The battery cell temperature acquisition module is configured to acquire battery cell temperatures of each battery cell of the power battery when the first controller is in the sleep state. The wake-up instruction sending module is configured to send a wake-up instruction to the main controller when the minimum value of the battery cell temperatures is less than or equal to the current wake-up temperature, wherein the wake-up instruction carries the minimum value of the battery cell temperatures, so that the first controller estimates a target remaining power and a target battery cell temperature of the power battery after heating according to the minimum value of the battery cell temperatures, the current wake-up temperature, a current remaining power of the power battery, and a unit energy consumption temperature rise, and performs heating control on the power battery according to the target remaining power and the target battery cell temperature.

12. A temperature control device for a power cell, comprising a processor and a memory, characterized in that The memory stores computer program instructions that can be executed by the processor, and the processor executes the computer program instructions to implement the steps of the method according to any one of claims 1 to 9.

13. A computer-readable storage medium, characterized in that, The computer readable storage medium stores computer program instructions, and the computer program instructions are executed by the processor to cause the processor to implement the steps of the method according to any one of claims 1 to 9.

14. A computer program product, characterised in that, The computer program is executed by the processor to cause the processor to implement the steps of the method according to any one of claims 1 to 9.

15. A vehicle characterized by comprising: The temperature control device of the power battery according to claim 12 and the power battery, wherein the temperature control device of the power battery comprises a first controller and a second controller of a battery management system, and the power supply of the first controller is different from the power supply of the second controller.

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