Battery control method and device, vehicle-mounted controller and vehicle

Abstract

The application discloses a battery control method and device, a vehicle-mounted controller and a vehicle, and belongs to the technical field of battery management. The method comprises the following steps: acquiring a temperature rise coefficient of a power battery, wherein the temperature rise coefficient is used for reflecting the temperature rise rate of the power battery under the conditions of being heated and self-heating; determining a maximum discharge power according to the temperature rise coefficient, wherein the maximum discharge power is determined according to the discharge power of the power battery corresponding to a target temperature rise path, the target temperature rise path is a path for the power battery to rise from a current temperature to a target temperature under the temperature rise coefficient, and the target temperature is a temperature at which the basic allowable power of the power battery at a target SOC satisfies a power threshold; and determining a target allowable power according to the maximum discharge power, wherein the target allowable power is used for limiting the output power of the power battery. The application can improve the endurance of the vehicle under a low-temperature working condition.

Description

Technical Field

[0001] This application relates to the field of battery management technology, and in particular to a battery control method, device, vehicle controller, and vehicle. Background Technology

[0002] Under low-temperature conditions, the polarization of a vehicle's power battery can become severe, leading to a decrease in its discharge capacity.

[0003] In related technologies, by setting thermal management strategies for power batteries, it is possible to determine when and at what level the power batteries should be heated, thereby raising the temperature of the power batteries under low-temperature conditions, so that they can be moved out of the temperature range where their discharge capacity is extremely weak, and ensuring that the power batteries can discharge normally.

[0004] Since the battery temperature needs time to rise when it is heated, discharging the battery during this process may result in a poor driving range. Summary of the Invention

[0005] This application provides a battery control method, device, vehicle controller, and vehicle, which can improve the vehicle's range under low-temperature conditions. The technical solution is as follows: According to one aspect of this application, a battery control method is provided, the method comprising: The temperature rise coefficient of the power battery is obtained, which reflects the rate of temperature increase of the power battery under heating and self-heating conditions. The maximum discharge power is determined based on the temperature rise coefficient. The maximum discharge power is determined based on the discharge power of the power battery under the target temperature rise path. The target temperature rise path is the path of the power battery from the current temperature to the target temperature under the temperature rise coefficient. The target temperature is the temperature at which the basic allowable power of the power battery under the target state of charge (SOC) meets the power threshold. The target allowable power is determined based on the maximum discharge power, and the target allowable power is used to limit the output power of the power battery.

[0006] According to another aspect of this application, a battery control device is provided, the device comprising: The acquisition module is used to acquire the temperature rise coefficient of the power battery, which reflects the rate of temperature increase of the power battery under heating and self-heating conditions. The determination module is used to determine the maximum discharge power based on the temperature rise coefficient. The maximum discharge power is determined based on the discharge power of the power battery under the target temperature rise path. The target temperature rise path is the path of the power battery from the current temperature to the target temperature under the temperature rise coefficient. The target temperature is the temperature at which the basic allowable power of the power battery under the target SOC meets the power threshold. The determining module is further configured to determine a target allowable power based on the maximum discharge power, wherein the target allowable power is used to limit the output power of the power battery.

[0007] In an optional design, the maximum discharge power is determined based on a target current, which is the current at which the power battery discharges according to the target duration corresponding to the target temperature rise path, and the target duration is the time it takes for the power battery to rise from the current temperature to the target temperature under the temperature rise coefficient.

[0008] In an optional design, the determining module is used for: Based on the correlation between the SOC, temperature and basic allowable power of the power battery, the target temperature corresponding to the target SOC of the power battery is determined. Determine a first difference between the target temperature and the current temperature of the power battery; The target duration is obtained by determining the quotient of the first difference and the temperature rise coefficient; The maximum discharge power is determined based on the target duration.

[0009] In an optional design, the determining module is used for: Determine the current capacity of the power battery based on its current state of charge (SOC). The target current is determined based on the quotient of the current capacity and the target duration; The maximum discharge power is determined by multiplying the target current by the current voltage of the power battery.

[0010] In an optional design, the determining module is used for: The basic allowable power of the power battery is determined based on its current temperature and current state of charge (SOC). The basic allowable power is adjusted based on the difference between the actual output power of the power battery and the maximum discharge power to obtain the adjusted allowable power; The target allowable power is determined based on the adjusted allowable power.

[0011] In an optional design, the determining module is used for: Determine a second difference between the actual output power and the maximum discharge power; The power derating amount is determined based on the second difference; The adjusted allowable power is determined based on the difference between the basic allowable power and the power derating.

[0012] In an optional design, the determining module is used for: The first value is determined by multiplying the second difference by the first coefficient; The second value is determined by the product of the integral of the second difference over time and the second coefficient; The power derating amount is determined based on the sum of the first value and the second value.

[0013] In an optional design, the determining module is used for: Determine the maximum value between the adjusted allowable power and the preset allowable power; The target allowable power is determined based on the minimum value between the maximum value and the basic allowable power.

[0014] In an optional design, the determining module is used for: The actual output power of the power battery during the first time period is obtained by low-pass filtering.

[0015] In an optional design, the acquisition module is used for: The thermal management heat exchange capacity of the power battery is obtained, and the thermal management heat exchange capacity is used to reflect the power for heating or dissipating heat from the power battery. The self-heating capacity of the power battery is obtained, and the self-heating capacity is used to reflect the ability of the power battery to convert electrical energy into heat energy during operation. The determining module is used for: The temperature rise rate is determined based on the heat exchange capacity of the thermal management system and the self-heating capacity of the battery. The temperature rise coefficient is determined based on the temperature rise rate.

[0016] In an optional design, the determining module is used for: The temperature rise rate determined within the second time period is low-pass filtered to obtain the temperature rise coefficient.

[0017] According to another aspect of this application, an on-board controller is provided, comprising: a processor and a memory, wherein the memory stores at least one program; the processor is used to execute the at least one program in the memory to implement the above-described battery control method.

[0018] According to another aspect of this application, a vehicle is provided, the vehicle including an on-board controller for performing the above-described battery control method.

[0019] According to another aspect of this application, a computer-readable storage medium is provided, which stores at least one program that is loaded and executed by a processor to implement the above-described battery control method.

[0020] According to another aspect of this application, a computer program product is provided, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the above-described battery control method.

[0021] The beneficial effects of the technical solution provided in this application include at least the following: By determining the target allowable power of the power battery and then limiting its output power accordingly, it is possible to limit the power battery's output power during the temperature rise process from low temperature. Since the target allowable power is determined based on a target temperature rise path—a path that simultaneously satisfies the conditions of optimal range and minimum heating energy consumption—it is possible to limit the power battery's output power according to this optimal temperature rise path. This forces the power battery to discharge along this path, thus helping to improve the vehicle's range under low-temperature conditions. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of an interval provided in an exemplary embodiment of this application; Figure 2 This is a schematic diagram of a trajectory provided in an exemplary embodiment of this application; Figure 3 This is a schematic diagram of a vehicle system provided in an exemplary embodiment of this application; Figure 4 This is a schematic diagram illustrating the process of determining the allowable power of a power battery according to an exemplary embodiment of this application; Figure 5 This is a schematic flowchart of a battery control method provided in an exemplary embodiment of this application; Figure 6 This is a schematic flowchart of a battery control method provided in an exemplary embodiment of this application; Figure 7 This is a schematic diagram of a first difference provided in an exemplary embodiment of this application; Figure 8 This is a schematic diagram of the process for determining the maximum discharge power provided in an exemplary embodiment of this application; Figure 9 This is a power schematic diagram provided in an exemplary embodiment of this application; Figure 10 This is a schematic diagram of a process for controlling the output power of a power battery according to an exemplary embodiment of this application; Figure 11 This is a schematic diagram of the structure of a battery control device provided in an exemplary embodiment of this application; Figure 12 This is a structural block diagram of an on-board controller provided in an exemplary embodiment of this application.

[0024] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0026] Under low-temperature conditions, the polarization of a vehicle's power battery can become severe, leading to a decrease in its discharge capacity. Related technologies employ thermal management strategies tailored to the power battery to determine when and at what level to heat it. This raises the battery's temperature in low-temperature conditions, moving it out of its extremely low-discharge-capacity range and ensuring normal discharge.

[0027] However, the above solutions overlook the time required for the battery temperature to rise. If the battery discharges at a high power rate and consumes power rapidly during the heating process, it may fail to reach the heating temperature determined by the thermal management strategy in time. This could cause the battery to prematurely enter a low-temperature, low-charge state (SOC) range with extremely weak discharge capacity, rendering it unable to support continued vehicle use / driving and resulting in poor driving range. In summary, to achieve optimal driving range, not only does the battery's thermal management require a better strategy, but the battery's output power must also be appropriately matched to prevent extremely poor driving range under certain driving conditions (high discharge power) in extremely low temperatures, where the thermal management strategy is completely ineffective in addressing the poor driving range issue.

[0028] This application primarily addresses the issue that when a power battery discharges under low-temperature conditions, relying solely on thermal management strategies and the battery's self-heating can lead to a rapid drop in the State of Charge (SOC) to a point where the battery's discharge capacity is extremely low, resulting in the battery being deemed depleted and the vehicle's range reaching its limit. This application aims to achieve the goal of meeting the vehicle's basic power requirements while allowing sufficient time for the thermal management system to heat the power battery. This allows the battery to move out of the aforementioned extremely low discharge capacity range, enabling it to release more electricity and extend the vehicle's driving range. The principles involved in this application are illustrated below.

[0029] During the discharge process of the power battery (battery pack), the vehicle controller continuously monitors the power battery's SOC, temperature, individual cell voltage, and discharge current. The Battery Management System (BMS) uses internal software lookup tables to obtain the basic allowable power P based on the power battery's SOC and temperature. base This parameter table, derived from offline testing, characterizes the maximum discharge power of a power battery under normal operating conditions at different temperatures and SOC levels. Generally, under low temperature and low SOC conditions, the battery's discharge capacity is very weak, and the result obtained from the table will be very small. Discharging the battery at this maximum power may not be sufficient to support a satisfactory driving experience. Therefore, it is stipulated that if the battery temperature and SOC reach this range, it is considered the end of the battery's driving range. At this point, the user will be notified in various ways that the battery is low on power (e.g., the displayed SOC percentage will drop to 0%, thus reminding the user that the battery is dead and the vehicle can no longer be driven). For example, Figure 1 This is a schematic diagram of a range provided in an exemplary embodiment of this application. For example... Figure 1 As shown, based on the SOC and temperature of the power battery, intervals 101 and 102 can be divided. When the SOC and temperature of the power battery are in interval 101, the power battery is considered to be depleted, that is, the power battery's driving range has reached its limit.

[0030] As mentioned earlier, during vehicle operation, the SOC and temperature of the power battery continuously change, and the corresponding points for SOC and temperature can be... Figure 1 A trajectory (temperature rise path) is formed in the middle. For example, Figure 2 This is a schematic diagram of a trajectory provided in an exemplary embodiment of this application. For example... Figure 2As shown, the ΔSOC (the difference between the initial SOC and the final SOC) that can be released varies under different trajectories, and the temperature change ΔT (the difference between the initial temperature and the final temperature) also varies. ΔSOC can be considered to represent the vehicle's range; the larger the value, the longer the range. ΔT, to some extent, represents energy consumption; the larger the value, the higher the energy used to heat the battery in the low-temperature range, i.e., the higher the energy consumption. Generally speaking, the lower the ΔT, the better. The lowest limit is when the battery is not heated by the thermal management system at all, and its temperature rises purely through its own self-heating during use. Figure 2 Taking the temperature rise paths shown as an example, the ΔSOC released by temperature rise paths 2 and 3 is greater than that of temperature rise path 1. Assuming that temperature rise path 1 is a self-heating path of the power battery (without thermal management system heating), then both temperature rise paths 2 and 3 will involve a certain degree of energy consumption by the thermal management system to heat the power battery. Furthermore, since the ΔT of temperature rise path 3 is greater than that of temperature rise path 2, it means that the energy consumption of temperature rise path 3 will theoretically be greater than that of temperature rise path 2. It is not difficult to see that if we want to achieve the goal of optimal energy consumption under the condition of maximum range, then temperature rise path 2 is theoretically the best among the three temperature rise paths (the range is longer than that of temperature rise path 1 while the thermal management energy consumption is smaller than that of temperature rise path 3).

[0031] The objective of this application is to minimize energy consumption while achieving optimal battery life; that is, in this application, the aforementioned Figure 2 Temperature rise path 2 is the optimal temperature rise path among the three. This application achieves the above objective by determining the target allowable power of the power battery under temperature rise path 2 and limiting the output power of the power battery according to the target allowable power, thereby driving the power battery to discharge according to temperature rise path 2.

[0032] Figure 3 This is a schematic diagram of a vehicle system provided in an exemplary embodiment of this application. For example... Figure 3 As shown, the vehicle system 300 includes a power battery system 301, a high-voltage distribution box 302, a vehicle control unit (VCU) 303, and a high-voltage subsystem.

[0033] The power battery system 301, as the source of high-voltage energy for the vehicle, provides the required energy and power to meet the vehicle's driving needs. The power battery system 301 integrates a battery management system (BMS) 304, responsible for real-time monitoring of the power battery status and ensuring its safety and performance. The high-voltage distribution box 302 is the hub for high-voltage power distribution, directly receiving the high-voltage electricity output from the power battery system 301 and distributing it to multiple downstream high-voltage subsystems. The vehicle controller 303, as the core unit of vehicle control, is connected to the battery management system 304 and each downstream high-voltage subsystem via communication lines, coordinating the operating strategies of each component to achieve coordinated control of vehicle power, charging, thermal management, and other functions. The high-voltage subsystems include the drive system 305, charging system 306, thermal management system 307, and other high-voltage systems 308. The high-voltage power supply for all high-voltage subsystems is uniformly distributed by the high-voltage distribution box 302 and simultaneously managed and controlled by the vehicle controller 303.

[0034] For example, the dynamic allowable power regulation control strategy provided in this application during the power battery discharge process is deployed in the battery management system 304. During the vehicle discharge process, the dynamic allowable power is sent to the vehicle controller 303 so that the maximum power used by the controller cannot exceed the limit given by the battery management system 304.

[0035] Figure 4 This is a schematic diagram illustrating the process of determining the allowable power of a power battery according to an exemplary embodiment of this application. Figure 4 As shown, the vehicle controller acquires the temperature rise coefficient 401 of the power battery and determines the maximum discharge power 402 of the power battery based on the temperature rise coefficient 401. Then, it determines the target allowable power 403 of the power battery based on the maximum discharge power 402. The temperature rise coefficient 401 reflects the rate of temperature increase of the power battery under both heating and self-heating conditions. The maximum discharge power 402 of the power battery can be understood as the maximum power that the power battery can output under the conditions of maximizing driving range and optimizing energy consumption. The target allowable power 403 is used to limit the output power of the power battery; that is, after determining the target allowable power 403, the vehicle controller will control the output power of the power battery to ensure that it does not exceed the target allowable power 403.

[0036] In some embodiments, the on-board controller determines a target temperature 404 corresponding to the target SOC of the power battery, and determines a target duration 405 based on the target temperature 404, the current temperature of the power battery, and the temperature rise coefficient 401. The target temperature 404 is the temperature at which the basic allowable power 407 of the power battery at the target SOC meets a power threshold. The power threshold is preset, for example, based on the minimum power required to meet vehicle driving needs. The target duration 405 is the time it takes for the power battery to rise from its current temperature to the target temperature 404. The target SOC can refer to SOC = 0%. The on-board controller then determines a target current 406 based on the target duration 405, and determines a maximum discharge power 402 based on the target current 406. The target current 406 is the average current of the power battery discharging to the target SOC according to the target duration 405.

[0037] Given a maximum discharge power 402, the vehicle controller controls the battery's output power to ensure that the actual output power 408 of the battery does not exceed this maximum discharge power 402. Optionally, the vehicle controller uses proportional-integral (PI) control to ensure that the actual output power 408 of the battery does not exceed the maximum discharge power 402. For example, the vehicle controller determines the battery's basic allowable power 407 based on the battery's current temperature and current state of charge (SOC). It then adjusts the basic allowable power 407 based on the difference between the actual output power 408 and the maximum discharge power 402, resulting in an adjusted allowable power. Finally, a target allowable power 403 is determined based on the adjusted allowable power. By limiting the target allowable power 403, the actual output power 408 of the battery can be kept below the maximum discharge power 402.

[0038] By determining the target allowable power of the power battery and then limiting its output power accordingly, it is possible to limit the power battery's output power during the temperature rise process from low temperature. Since the target allowable power is determined based on a target temperature rise path—a path that simultaneously satisfies the conditions of optimal range and minimum heating energy consumption—it is possible to limit the power battery's output power according to this optimal temperature rise path. This forces the power battery to discharge along this path, thus helping to improve the vehicle's range under low-temperature conditions.

[0039] Figure 5 This is a schematic flowchart illustrating a battery control method provided in an exemplary embodiment of this application. This method can be used in an vehicle controller, for example, for... Figure 3 The battery management system in the system shown. For example... Figure 5 As shown, the method includes: Step 502: Obtain the temperature rise coefficient of the power battery.

[0040] A power battery includes a battery used to provide electrical energy for the vehicle's power; a power battery can also be called a high-voltage battery. In some embodiments, the vehicle in this application includes at least one of a pure electric vehicle and a hybrid vehicle. In some embodiments, the vehicle in this application includes at least one of a four-wheeled vehicle, a two-wheeled vehicle, a three-wheeled vehicle, and a vehicle with other numbers of wheels. The vehicle controller in this application is a controller integrated into the vehicle for managing vehicle components. In some embodiments, the vehicle controller in this application includes a Battery Management System (BMS).

[0041] The temperature rise coefficient reflects the rate of temperature increase of a power battery under both heating and self-heating conditions. It can also be understood as the rate of temperature increase of the power battery during heating and self-heating processes. The self-heating of the power battery refers to the heat generated by the battery itself during operation / discharge.

[0042] Optionally, the temperature rise coefficient of the power battery is related to the power power used to heat the battery and the battery's self-heating capability. For example, the higher the power power used to heat the battery, the greater the temperature rise coefficient; the lower the power power used to heat the battery, the smaller the temperature rise coefficient. The stronger the battery's self-heating capability, the greater the temperature rise coefficient; the weaker the battery's self-heating capability, the smaller the temperature rise coefficient.

[0043] Step 504: Determine the maximum discharge power based on the temperature rise coefficient.

[0044] The maximum discharge power of a power battery is used to limit its output power. The maximum discharge power of a power battery can be understood as the maximum power it can output while simultaneously achieving the best driving range and optimal energy consumption. Alternatively, it can be understood as the maximum power that the battery can output under the following conditions: Figure 2 Under the condition of discharge via the second temperature rise path, the maximum power that the power battery can output is determined.

[0045] The maximum discharge power is determined based on the discharge power of the power battery under the target temperature rise path, and can also be understood as the discharge power used to limit the power battery from discharging along the target temperature rise path. The temperature rise path in this embodiment reflects the changes in the power battery's SOC and temperature; for details, please refer to the preceding text. Figure 2 The target temperature rise path can be understood as Figure 2Temperature rise path 2 is shown as one of the three temperature rise paths. The target temperature rise path is the path by which the power battery rises from its current temperature to the target temperature under the given temperature rise coefficient. For example, the target temperature rise path is the path by which the power battery discharges to the target SOC, or the path with the maximum discharge capacity or the largest decrease in SOC, within the path from the current temperature to the target temperature under the given temperature rise coefficient. The current temperature is the temperature of the power battery when the vehicle controller determines the maximum discharge power; it can also be understood as the real-time temperature of the power battery. It should be noted that other concepts involving "current" in this application can refer to the definition here.

[0046] The target temperature is higher than the current temperature. The target temperature is the temperature at which the basic allowable power of the power battery at the target SOC meets the power threshold, for example, the temperature at which the basic allowable power at the target SOC is greater than or equal to the power threshold. Optionally, the target temperature is the lowest temperature at which the basic allowable power of the power battery at the target SOC meets the power threshold. The target SOC is lower than the current SOC of the power battery. The target SOC can be preset. In some embodiments, the target SOC is 0%. The basic allowable power of the power battery is determined according to a preset correspondence, which includes the correspondence between different SOCs and different temperatures and different basic allowable powers. The preset correspondence can be implemented as the parameter table mentioned above. The power threshold is preset, for example, based on the minimum power required to meet vehicle driving needs.

[0047] For example, continue to refer to Figure 1 The power battery meets the power threshold in interval 102, but does not meet the power threshold in interval 101. With a target SOC of 0%, the target temperature is -5℃. It should be noted that the above target SOC setting corresponds to the condition of maximizing driving range, and the above target temperature selection corresponds to the condition of optimal energy consumption. Furthermore, SOC=0% does not mean that the power battery cannot discharge completely, because the power battery usually still reserves some energy at SOC=0%. Therefore, different temperatures will affect the basic allowable power of the power battery at SOC=0%.

[0048] Step 506: Determine the target allowable power based on the maximum discharge power.

[0049] The target allowable power is used to limit the output power of the power battery. For example, the vehicle controller controls the output power of the power battery according to the target allowable power to ensure that the output power of the power battery does not exceed the target allowable power. Optionally, the vehicle controller directly determines the maximum discharge power as the target allowable power, or adjusts the basic allowable power of the power battery according to the maximum discharge power, and determines the target allowable power based on the adjustment result of the basic allowable power.

[0050] It should be noted that because the data used to determine the target allowable power includes instantaneous data (such as the temperature rise coefficient and the current temperature), the target allowable power will change dynamically over time. Accordingly, the target allowable power can also be called the dynamic allowable power.

[0051] It should be noted that the method provided in this application embodiment can be used not only to control the output power of the vehicle's power battery, but also to control the output power of other power density batteries (such as the batteries of drones). This application embodiment does not limit this.

[0052] In summary, the method provided in this embodiment, by determining the target allowable power of the power battery and then limiting its output power accordingly, can limit the power battery's output power during the process of warming up from a low temperature. Since the target allowable power is determined based on a target temperature rise path, which simultaneously satisfies the conditions of optimal range and minimum heating energy consumption, the power battery's output power can be limited according to this optimal temperature rise path. This forces the power battery to discharge along this optimal temperature rise path, thus helping to improve the vehicle's range under low-temperature conditions.

[0053] Figure 6 This is a schematic flowchart illustrating a battery control method provided in an exemplary embodiment of this application. This method can be used in an vehicle controller, for example, for... Figure 3 The battery management system in the system shown. For example... Figure 6 As shown, the method includes: Step 602: Obtain the temperature rise coefficient of the power battery.

[0054] A power battery includes a battery used to provide electrical energy for the vehicle's power; a power battery can also be called a high-voltage battery. In some embodiments, the vehicle in this application includes at least one of a pure electric vehicle and a hybrid vehicle. The vehicle controller in this application is a controller integrated into the vehicle for managing vehicle components. In some embodiments, the vehicle controller in this application includes a Battery Management System (BMS).

[0055] The temperature rise coefficient reflects the rate of temperature increase of a power battery under both heating and self-heating conditions. It can also be understood as the rate of temperature increase of the power battery during heating and self-heating processes. The self-heating of the power battery refers to the heat generated by the battery itself during operation / discharge.

[0056] In some embodiments, the on-board controller acquires the thermal management heat transfer capability and the battery self-heating capability of the power battery. Then, based on these two capabilities, it determines the temperature rise rate of the power battery, and subsequently determines the temperature rise coefficient of the power battery. The thermal management heat transfer capability reflects the power power used to heat or dissipate heat from the power battery; it can also be understood as the heating power of the thermal management system for the power battery. The battery self-heating capability reflects the power battery's ability to convert electrical energy into heat energy during operation; it can also be understood as the power battery's self-heating power.

[0057] Optionally, the on-board controller determines the thermal management heat exchange capability of the power battery based on the inlet temperature, outlet temperature, thermal conductivity, and heat exchange efficiency of the heat exchange fluid. The thermal management heat exchange capability of the power battery can be calculated using the following formula: (1) in, This indicates the heat exchange capacity of thermal management, measured in W. Indicates the temperature of the inlet liquid. Indicates the outlet liquid temperature. This indicates the thermal conductivity of the heat transfer fluid, which is the heat transfer power that can be transferred per degree Celsius temperature difference, and the unit is W / ℃. This indicates the heat exchange efficiency of the power battery.

[0058] Optionally, the vehicle controller determines the battery's self-heating capability based on the battery's current, open circuit voltage (OCV), and voltage. The battery's self-heating capability can be calculated using the following formula: (2) in, This indicates the battery's self-heating capacity, measured in W. This indicates the current of the power battery, such as the current output current of the power battery. This indicates the open-circuit voltage of the power battery. For example, the current open-circuit voltage of the power battery can be obtained by looking up a table based on the current SOC of the power battery. The voltage of the power battery, such as the current voltage of the power battery, can be obtained by monitoring the voltage of the entire power battery pack, or by monitoring the voltage of all individual cells of the power battery and then adding them together.

[0059] The thermal management heat exchange capacity of a power battery is positively correlated with its temperature rise rate, as is its self-heating capacity. Optionally, the vehicle controller determines the temperature rise rate of the power battery based on its thermal management heat exchange capacity, self-heating capacity, thermal conductivity, and temperature rise conversion efficiency. The temperature rise rate of the power battery can be calculated using the following formula: (3) in, This indicates the rate of temperature rise of the power battery, measured in °C / s. Indicates the thermal conductivity of the power battery. This indicates the temperature rise conversion efficiency of the power battery. (Introduction) The reason is that the power battery exchanges heat with the environment, but not all of the heat exchange power and self-heating power will become the internal energy of the power battery to generate a temperature rise. Some of the energy will be dissipated into the environment.

[0060] By comprehensively determining the temperature rise rate of the power battery from two dimensions—thermal management heat exchange capacity (external heating) and battery self-heating capacity (internal electrical energy to heat energy conversion)—the temperature rise coefficient of the power battery can be obtained. The determined temperature rise coefficient can fully reflect the true temperature change characteristics of the power battery under the combined action of external thermal management and internal electrochemical reaction.

[0061] Optionally, when the temperature rise rate of the power battery is determined, the on-board controller directly determines the temperature rise rate of the power battery as the temperature rise coefficient, or performs low-pass filtering on the temperature rise rate determined within a past second time period to obtain the temperature rise coefficient. Here, the second time period can be a preset duration. Performing low-pass filtering on the temperature rise rate determined within the past second time period can be understood as performing long-term low-pass filtering on the previously determined temperature rise rate. Long-term low-pass filtering is used to filter out glitches in the data to determine the characteristics of the data over a period of time. When the temperature rise coefficient is determined through long-term low-pass filtering, the temperature rise coefficient can also be called the long-term temperature rise coefficient.

[0062] By applying a low-pass filter to the temperature rise rate over the past second time period to obtain the temperature rise coefficient, the influence of short-term fluctuations and outliers can be smoothed out, resulting in a more stable and reliable temperature rise coefficient. This avoids large fluctuations in subsequent power determination caused by drastic changes in the instantaneous temperature rise rate, thereby improving the reliability of power determination.

[0063] Step 604: Determine the maximum discharge power based on the temperature rise coefficient.

[0064] The maximum discharge power of a power battery is used to limit its output power. The maximum discharge power of a power battery can be understood as the maximum power it can output while simultaneously achieving the best driving range and optimal energy consumption. Alternatively, it can be understood as the maximum power that the battery can output under the following conditions: Figure 2 Under the condition of discharge via the second temperature rise path, the maximum power that the power battery can output is determined.

[0065] The maximum discharge power is used to limit the power battery to discharge according to the target temperature rise path. In this embodiment, the temperature rise path reflects the changes in the power battery's SOC and temperature. The target temperature rise path is the path the power battery takes from its current temperature to a target temperature under a given temperature rise coefficient. For example, the target temperature rise path is the path where the power battery discharges to the target SOC, or the path with the maximum discharge or the largest decrease in SOC, within the path from the current temperature to the target temperature under the given temperature rise coefficient. The target temperature rise path can be understood as... Figure 2 Temperature rise path 2 is shown as one of the three temperature rise paths. Optionally, the maximum discharge power is determined based on the target current, for example, based on the target current and the voltage of the power battery. The target current is the current at which the power battery discharges according to the target duration corresponding to the target temperature rise path, for example, the average current at which the power battery discharges to the target SOC according to the target duration, for example, determined based on the current capacity of the power battery and the target duration. The target duration is the time it takes for the power battery to rise from the current temperature to the target temperature under the temperature rise coefficient, and the target duration is related to the difference between the target temperature and the current temperature and the temperature rise coefficient.

[0066] The target temperature is higher than the current temperature. The target temperature is the temperature at which the basic allowable power of the battery at the target SOC meets a power threshold, for example, the temperature at which the basic allowable power at the target SOC is greater than or equal to the power threshold. Optionally, the target temperature is the lowest temperature at which the basic allowable power of the battery at the target SOC meets the power threshold. The target SOC is lower than the current SOC of the battery. The target SOC may be preset. In some embodiments, the target SOC is 0%. The power threshold is preset, for example, based on the minimum power required to meet vehicle driving needs.

[0067] Optionally, the vehicle controller determines the target temperature of the power battery at the target SOC based on the correlation between the battery's SOC, temperature, and basic allowable power. For example, when the target SOC is 0%, the vehicle controller determines the battery temperature when the basic allowable power equals the power threshold, thus obtaining the target temperature. After determining the target temperature, the vehicle controller determines the first difference between the target temperature and the current temperature of the power battery, and then determines the quotient of this first difference and the battery's temperature rise coefficient, thus obtaining the target duration. The vehicle controller then determines the maximum discharge power based on the target duration. The target duration can be calculated using the following formula: (4) (5) in, Indicates the target temperature. This indicates the current temperature of the power battery. This represents the first difference. Indicates the target duration. This represents the temperature rise coefficient. For example, Figure 7 This is a schematic diagram of a first difference provided in an exemplary embodiment of this application. (See diagram below.) Figure 7 As shown, the vehicle controller first determines the target temperature corresponding to the power battery, and then determines the first difference based on the target temperature and the current temperature.

[0068] By determining the target temperature through the correlation between the SOC, temperature, and basic allowable power of the power battery, and then combining the current temperature to calculate the temperature difference and target duration, the process of determining the maximum discharge power has a clear physical meaning and an operable calculation path, thus improving the accuracy of power determination.

[0069] Optionally, the vehicle controller determines the current capacity of the power battery based on its current state of charge (SOC). The current capacity can also be understood as the capacity to be discharged. For example, the vehicle controller obtains the nominal capacity of the power battery and calculates the product of the nominal capacity and the current SOC to obtain the current capacity. Then, the vehicle controller determines the target current based on the quotient of the current capacity and the target duration, and determines the maximum discharge power based on the product of the target current and the current voltage of the power battery. The target current can also be called the maximum allowable average discharge current, and the maximum discharge power can also be called the maximum allowable average discharge power. The target current can be calculated using the following formula: (6) (7) in, This indicates the current capacity of the power battery. Indicates the current SOC of the power battery. For the target SOC, This indicates the nominal capacity of the power battery. Indicates the target current.

[0070] For example, Figure 8 This is a schematic diagram illustrating the process of determining the maximum discharge power according to an exemplary embodiment of this application. Figure 8As shown, the vehicle controller determines the thermal management heat exchange capacity 802 of the power battery based on the thermal management circuit parameter 801, and determines the battery self-heating capacity 804 of the power battery based on the power battery parameter 803. Then, it determines the temperature rise coefficient 805 based on the thermal management heat exchange capacity 802 and the battery self-heating capacity 804, and determines the target duration 807 based on the first difference 806 determined by the target temperature and the current temperature. Then, it determines the target current based on the target duration 807, and determines the maximum discharge power 808 based on this.

[0071] By determining the current capacity based on the current SOC of the power battery, obtaining the target current by dividing the current capacity by the target duration, and finally calculating the maximum discharge power of the power battery in combination with the current voltage, the real-time state parameters such as the current capacity and voltage of the power battery are fully considered, making the calculation of the maximum discharge power more in line with the actual working conditions of the power battery and improving the accuracy of power determination.

[0072] Step 606: Determine the basic allowable power of the power battery based on its current temperature and current SOC.

[0073] The basic allowable power of the power battery is determined according to a preset correspondence, which includes the correspondence between different states of charge (SOC) and different temperatures and different basic allowable powers. This preset correspondence can be implemented as the parameter table mentioned earlier. The vehicle controller can determine the corresponding basic allowable power based on the current temperature and current SOC of the power battery through the preset correspondence.

[0074] Step 608: Adjust the basic allowable power based on the difference between the actual output power and the maximum discharge power of the power battery to obtain the adjusted allowable power.

[0075] The actual output power of the power battery is the power actually output during the discharge process. Optionally, the on-board controller performs low-pass filtering on the actual output power of the power battery within a past first time period to obtain the actual output power. Here, the first time period can be a preset duration. Low-pass filtering on the actual output power of the power battery within the past first time period can be understood as performing long-term low-pass filtering on the past actual output power of the power battery. Long-term low-pass filtering is used to filter out glitches in the data to determine the characteristics of the data over a period of time. When the actual output power is determined through long-term low-pass filtering, the actual output power can also be referred to as the long-term actual power.

[0076] By applying a low-pass filter to the actual output power of the power battery during the first time period, the smoothed actual output power is obtained. This effectively filters out high-frequency noise and transient fluctuations in the power signal, avoids frequent and large adjustments to the allowable power due to instantaneous power spikes, makes the power limiting strategy more stable and reliable, and improves the stability of the system.

[0077] Optionally, the on-board controller adjusts the basic allowable power using PI control to obtain the adjusted allowable power. During this process, the on-board controller determines a second difference between the actual output power and the maximum discharge power, and determines a power derating amount based on this second difference. The power derating amount is used to adjust the basic allowable power. Then, the on-board controller determines the adjusted allowable power based on the difference between the basic allowable power and the power derating amount.

[0078] The power derating is determined by the difference between the actual output power and the maximum discharge power. By deducting from the basic allowable power, the degree of power overrun is quantified into a specific power derating, making the adjustment process controllable and realizing a more refined power management strategy.

[0079] Optionally, when adjusting the basic allowable power based on PI control, in determining the power derating, the on-board controller determines a first value based on the product of a second difference and a first coefficient, and a second value based on the product of the integral of the second difference over time and the second coefficient. Then, the power derating is determined based on the sum of the first and second values. Here, the first coefficient can be called the proportional coefficient, and the first value can be called the proportional derating. The second coefficient can be called the integral coefficient, and the second value can be called the integral derating. The integral of the second difference over time refers to the integration over time starting from the target time, where the target time is the moment when the output power of the power battery is controlled using the method provided in this application embodiment. The adjusted allowable power can be calculated using the following formula: (8) (9) (10) in, This indicates the adjusted allowable power. Indicates the basic allowable power. This indicates the power derating amount. Indicates the second difference. Indicates the actual output power. This indicates the maximum discharge power. Indicates the first coefficient. This represents the second coefficient.

[0080] The power derating is determined by considering not only the instantaneous difference between the actual output power and the maximum discharge power (proportional term), but also the cumulative effect of this difference over time (integral term). This allows for simultaneous responses to both short-term power spikes and sustained power overruns, making the derating strategy more reasonable.

[0081] Step 610: Determine the target allowable power based on the adjusted allowable power.

[0082] The target allowable power is used to limit the output power of the power battery. For example, the vehicle controller controls the output power of the power battery according to the target allowable power so that the output power of the power battery does not exceed the target allowable power.

[0083] By introducing a mechanism that dynamically adjusts the basic allowable power based on the difference between the actual output power and the maximum discharge power, the target allowable power not only depends on the temperature and SOC state of the power battery, but can also be adaptively corrected according to the real-time discharge situation, thereby making fuller use of the power battery's discharge capacity while ensuring range.

[0084] Optionally, the vehicle controller may directly determine the adjusted allowable power as the target allowable power, or determine the target allowable power by combining information other than the adjusted allowable power. For example, the vehicle controller may determine the maximum value between the adjusted allowable power and the preset allowable power, and determine the target allowable power based on the minimum value between this maximum value and the basic allowable power. The preset allowable power is pre-set, for example, based on the minimum power required to meet the vehicle's driving experience. The target allowable power can be determined using the following formula: (11) in, Indicates the target allowable power. This indicates the adjusted allowable power. Indicates the preset allowable power. This indicates the basic allowable power.

[0085] The target allowable power is determined by taking the maximum value of the adjusted allowable power and the preset allowable power, and then taking the minimum value of the basic allowable power. This sets reasonable upper and lower limits for the target allowable power, ensuring that it is not lower than the preset minimum power, while avoiding the risk of over-discharge caused by exceeding the basic allowable power. This enhances the safety redundancy of power management while ensuring the driving experience.

[0086] For example, Figure 9 This is a power schematic diagram provided in an exemplary embodiment of this application. For example... Figure 9 As shown, Figure 9 The effect of adjusting the baseline allowable power through PI control to limit the actual output power of the power battery is shown.

[0087] It should be noted that because the data used to determine the target allowable power includes instantaneous data (such as the temperature rise coefficient and the current temperature), the target allowable power will change dynamically over time. Accordingly, the target allowable power can also be called the dynamic allowable power.

[0088] In summary, the method provided in this embodiment, by determining the target allowable power of the power battery and then limiting its output power accordingly, can limit the power battery's output power during the process of warming up from a low temperature. Since the target allowable power is determined based on a target temperature rise path, which simultaneously satisfies the conditions of optimal range and minimum heating energy consumption, the power battery's output power can be limited according to this optimal temperature rise path. This forces the power battery to discharge along this optimal temperature rise path, thus helping to improve the vehicle's range under low-temperature conditions.

[0089] The method provided in this application includes: determining the basic allowable power of the power battery, determining the temperature rise coefficient of the power battery based on thermal management heating and the self-heating of the power battery, determining the discharge time and maximum discharge power required for the ideal temperature rise path according to the temperature rise coefficient, and then controlling the allowable power derating of the power battery to ensure that the power battery can discharge according to the temperature rise path as much as possible to extend the driving range.

[0090] For example, Figure 10 This is a schematic diagram illustrating the process of controlling the output power of a power battery according to an exemplary embodiment of this application. Figure 10 As shown, in step S1, the basic allowable power of the power battery is determined.

[0091] In step S2, the thermal management heat transfer capacity Q of the power battery is calculated. heat The calculation can be performed using the heat loss from the heating circuit, or other methods. For example, assuming the inlet liquid temperature T in the thermal management circuit of the power battery is known... in outlet liquid temperature T out Heat exchange liquid thermal conductivity G th The heat exchange efficiency of the power battery is η ex The heat exchange capacity of thermal management can be calculated using the formula mentioned above.

[0092] In step S3, the self-heating capacity Q of the power battery is calculated. self The calculation method can be simplified by treating the power battery as a pure resistive model. Voltage divisions, except for the initial voltage drop (OCV), are caused by pure resistance and generate heat. Specifically, the current OCV is obtained by looking up a table (the table lookup is determined through prior testing and is an inherent characteristic of each battery type), and the current overall battery voltage U can be monitored through voltage sampling. pack (Or, the voltage of all individual cells in the battery pack can be sampled and monitored, and then summed to obtain the total pack voltage), and the battery pack output current I. pack (If the discharge direction is defined as positive and the charging direction as negative), the battery's self-heating capacity can be calculated using the formula mentioned above.

[0093] In step S4, after obtaining the thermal management heat transfer capacity and the battery self-heating power, the temperature rise rate R of the power battery can be calculated. batt For each battery pack, its thermal conductivity G will be determined in advance through testing. batt And the temperature rise conversion efficiency η of the battery in low-temperature environments. re (Because the battery exchanges heat with the environment, not all of the heat exchange power and self-heating power will become the battery's internal energy and cause a temperature rise; some will be dissipated into the environment.) Therefore, the temperature rise rate can be calculated using the formula mentioned above.

[0094] In steps S5-S7, the temperature rise rate is subjected to long-term low-pass filtering to obtain a relatively stable temperature rise coefficient R. batt,LP Once this temperature rise coefficient is obtained, the temperature rise path from the current vehicle state of discharge to depletion can be planned, which means the above-mentioned... Figure 2 The second temperature rise path in the diagram involves monitoring the current temperature T of the power battery (for the battery pack, due to the bottleneck effect, this refers to the lowest temperature of a single cell) and the current State of Charge (SOC, similarly, due to the bottleneck effect, this refers to the lowest SOC of a single battery cell). Assuming SOC = 0%, the temperature at which the battery power capability is considered insufficient is T0. Then, the required temperature rise ΔT of the power battery can be obtained. Dividing the required temperature rise ΔT by the temperature rise coefficient yields the target time t required to reach the target temperature. need Discharging from the current SOC to 0% yields the required discharge capacity ΔQ, which is the ratio of the current SOC to the battery's nominal capacity Q. nom The product of ΔQ and t. Divide the required discharge capacity ΔQ by the target duration t. need The maximum permissible average discharge current (target current) I can be obtained. max,allw The maximum permissible average discharge current I was obtained through calculation. max,allw Multiply by the current voltage U pack The dynamic maximum permissible average discharge power (maximum discharge power) P is obtained. max,allw .

[0095] In steps S8-S11, the actual output power P of the power battery is monitored. act The actual output power P is obtained by performing a long-term low-pass filter on it. act,LP This represents the vehicle's driving habits over a relatively long period during this driving journey, and can make some predictions about future operating conditions. The P mentioned earlier... max,allw The goal is to prevent the actual output power from being exceeded for an extended period. Therefore, a constant-target control logic needs to be established. This logic can be implemented using various methods from automatic control theory, such as PI control. The control target is the maximum discharge power P. max,allwThe object of observation is the actual output power P. act,LP The controlled object is the basic allowable power P. base The control logic ensures the actual output power P by reducing the allowable power of the BMS output. act,LP It will not exceed the maximum discharge power P for an extended period of time. max,allw The allowable power should be suppressed as much as possible. Assume the allowable power after algorithm control (adjusted allowable power) is P. dy It is equal to the basic allowable power P. base Subtract the controlled power derating ΔP. This power derating is calculated by the PI control, i.e., calculating the actual output power P. act,LP With maximum discharge power P max,allw The difference ΔP obsr Multiply by the set proportional coefficient k p The proportional derating is obtained by integrating this power difference over time and multiplying it by the integration coefficient k. i The integral derating is obtained, and the sum of the two is the total power derating.

[0096] It should be noted that the power derating mentioned above cannot be too large. If the allowable power is reduced without limit simply to extend the driving range, it will result in insufficient vehicle power and a very poor driving experience. Therefore, a minimum base power (preset allowable power) P is defined. low This minimum base power ensures a normal driving experience for the vehicle without excessively reducing its power performance. The power limit (target allowable power) adjusted in this application will not be lower than this value (if it is lower, it will be limited to this value), unless the base allowable power P before algorithm control is reached. base It is already below this minimum base power P low This threshold is generally in the tens of kW range and depends on the specific vehicle model and other controls such as electric drive.

[0097] By limiting the vehicle's maximum operating power to the target allowable power controlled according to the above scheme, the vehicle can achieve the longest possible range while ensuring its power. In addition, several phenomena involved in this application need to be explained. First, if the calculated maximum discharge power P... max,allw Compared to the actual output power P act,LP It needs to be even larger, which means that the current allowable power does not need to be included in the limitations of this application, that is, it can be based on the basic allowable power P. base Limiting the overall vehicle power usage will not cause entry Figure 1 The interval 101 (meaning the power is cut off before the SOC reaches 0) indicates that, according to the current temperature rise path after thermal management intervention, at least... Figure 2The temperature rise path shown is 2, or even 3. This could be due to excessive heating from thermal management, or even without thermal management, the temperature rise from the battery's own heating is sufficient, or the battery's operating temperature is inherently high. Secondly, because all the above variables are calculated in real-time during driving, they are affected by various factors, leading to variations in the maximum discharge power P. max,allw The calculation results may change. For example, a change in the thermal management's ability to heat the battery, or more heat being diverted from the passenger compartment, can indirectly lead to a decrease in the maximum discharge power P. max,allw The calculated result decreases, while the increased heating level of thermal management leads to increased heating power to the battery, which in turn increases the calculated result. Alternatively, prolonged aggressive driving with high power demand can also increase the actual output power P. act,LP A large value will also indirectly lead to a decrease in the maximum discharge power P. max,allw The calculated result decreases, which in turn leads to a decrease in the allowable power P after control. dy,fnl This reduces the vehicle's permissible power output. While this reduction makes driving more relaxed, after a period of time, the actual output power P... act,LP As the power derating caused by the algorithm gradually decreases, it will slowly diminish.

[0098] The method provided in this application addresses the issue that relying solely on the thermal management system's strategy to heat the power battery at low temperatures may not guarantee the longest possible driving range. Even with sufficient heating, aggressive driving habits can cause the battery charge to drop rapidly, and the thermal management system may not provide enough time to fully heat the battery to a level suitable for charge release. This method, from the perspective of battery power capability control, indirectly suppresses aggressive driving by limiting the allowable power of the power battery. While ensuring the power capability required for a comfortable driving experience, extending the discharge time provides the thermal management system with sufficient time to heat the power battery, thereby improving the battery's performance at low SOC and thus enhancing the driving range.

[0099] It should be noted that this application may display prompt interfaces, pop-ups, or output voice prompts before and during the collection of user data. These prompt interfaces, pop-ups, or voice prompts are used to inform the user that their data is being collected. This ensures that the application only begins the steps for collecting user data after receiving confirmation from the user regarding the prompt interface or pop-up; otherwise (i.e., without user confirmation), the steps for collecting user data end, meaning no user data is collected. In other words, all user data collected in this application is collected with the user's consent and authorization, and the collection, use, and processing of related user data must comply with the relevant laws, regulations, and standards of the relevant countries and regions.

[0100] It should be noted that the order of the method steps provided in the embodiments of this application can be appropriately adjusted, and the steps can also be added or removed as appropriate. Any method variations that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the protection scope of this application, and therefore will not be elaborated further.

[0101] Figure 11 This is a schematic diagram of the structure of a battery control device provided in an exemplary embodiment of this application. Figure 11 As shown, the device includes: The acquisition module 1101 is used to acquire the temperature rise coefficient of the power battery, which reflects the rate of temperature increase of the power battery under heating and self-heating conditions. The determining module 1102 is used to determine the maximum discharge power according to the temperature rise coefficient. The maximum discharge power is determined according to the discharge power of the power battery under the target temperature rise path. The target temperature rise path is the path of the power battery from the current temperature to the target temperature under the temperature rise coefficient. The target temperature is the temperature at which the basic allowable power of the power battery under the target SOC meets the power threshold. The determining module 1102 is further configured to determine a target allowable power based on the maximum discharge power, wherein the target allowable power is used to limit the output power of the power battery.

[0102] In an optional design, the maximum discharge power is determined based on a target current, which is the current at which the power battery discharges according to the target duration corresponding to the target temperature rise path, and the target duration is the time it takes for the power battery to rise from the current temperature to the target temperature under the temperature rise coefficient.

[0103] In an optional design, the determining module 1102 is used for: Based on the correlation between the SOC, temperature and basic allowable power of the power battery, the target temperature corresponding to the target SOC of the power battery is determined. Determine a first difference between the target temperature and the current temperature of the power battery; The target duration is obtained by determining the quotient of the first difference and the temperature rise coefficient; The maximum discharge power is determined based on the target duration.

[0104] In an optional design, the determining module 1102 is used for: Determine the current capacity of the power battery based on its current state of charge (SOC). The target current is determined based on the quotient of the current capacity and the target duration; The maximum discharge power is determined by multiplying the target current by the current voltage of the power battery.

[0105] In an optional design, the determining module 1102 is used for: The basic allowable power of the power battery is determined based on its current temperature and current state of charge (SOC). The basic allowable power is adjusted based on the difference between the actual output power of the power battery and the maximum discharge power to obtain the adjusted allowable power; The target allowable power is determined based on the adjusted allowable power.

[0106] In an optional design, the determining module 1102 is used for: Determine a second difference between the actual output power and the maximum discharge power; The power derating amount is determined based on the second difference; The adjusted allowable power is determined based on the difference between the basic allowable power and the power derating.

[0107] In an optional design, the determining module 1102 is used for: The first value is determined by multiplying the second difference by the first coefficient; The second value is determined by the product of the integral of the second difference over time and the second coefficient; The power derating amount is determined based on the sum of the first value and the second value.

[0108] In an optional design, the determining module 1102 is used for: Determine the maximum value between the adjusted allowable power and the preset allowable power; The target allowable power is determined based on the minimum value between the maximum value and the basic allowable power.

[0109] In an optional design, the determining module 1102 is used for: The actual output power of the power battery during the first time period is obtained by low-pass filtering.

[0110] In an optional design, the acquisition module 1101 is used for: The thermal management heat exchange capacity of the power battery is obtained, and the thermal management heat exchange capacity is used to reflect the power for heating or dissipating heat from the power battery. The self-heating capacity of the power battery is obtained, and the self-heating capacity is used to reflect the ability of the power battery to convert electrical energy into heat energy during operation. The determining module 1102 is used for: The temperature rise rate is determined based on the heat exchange capacity of the thermal management system and the self-heating capacity of the battery. The temperature rise coefficient is determined based on the temperature rise rate.

[0111] In an optional design, the determining module 1102 is used for: The temperature rise rate determined within the second time period is low-pass filtered to obtain the temperature rise coefficient.

[0112] It should be noted that the battery control device provided in the above embodiments is only an example of the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the battery control device and the battery control method embodiments provided in the above embodiments belong to the same concept, and the specific implementation process can be found in the method embodiments, which will not be repeated here.

[0113] This application also provides an on-board controller, which includes a processor and a memory, wherein the memory stores at least one program; the processor is used to execute the at least one program in the memory to implement the battery control method provided in the above-described method embodiments.

[0114] Figure 12 This is a structural block diagram of an in-vehicle controller provided in an exemplary embodiment of this application. Typically, the in-vehicle controller 1200 includes a processor 1201 and a memory 1202.

[0115] Processor 1201 may include one or more processing cores, such as a quad-core processor, a 12-core processor, etc. Processor 1201 may be implemented using at least one hardware form selected from Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), and Programmable Logic Array (PLA). Processor 1201 may also include a main processor and a coprocessor. The main processor, also known as the Central Processing Unit (CPU), is used to process data in the wake-up state; the coprocessor is a low-power processor used to process data in the standby state. In some embodiments, processor 1201 may include a Graphics Processing Unit (GPU), which is responsible for rendering and drawing the content required to be displayed on the screen. In some embodiments, processor 1201 may also include an Artificial Intelligence (AI) processor, which is used to handle computational operations related to machine learning.

[0116] The memory 1202 may include one or more computer-readable storage media, which may be non-transitory. The memory 1202 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory devices. In some embodiments, the non-transitory computer-readable storage media in the memory 1202 are used to store at least one instruction, which is executed by the processor 1201 to implement the battery control method provided in the method embodiments of this application.

[0117] In some embodiments, the vehicle controller 1200 may also optionally include an input interface 1203 and an output interface 1204. The processor 1201, memory 1202, and input interfaces 1203 and 1204 can be connected via a bus or signal lines. Various peripheral devices can be connected to the input interfaces 1203 and 1204 via a bus, signal lines, or a circuit board. The input interfaces 1203 and 1204 can be used to connect at least one input / output related peripheral device to the processor 1201 and memory 1202.

[0118] In some embodiments, the processor 1201, memory 1202, and input interface 1203 and output interface 1204 are integrated on the same chip or circuit board; in some other embodiments, any one or two of the processor 1201, memory 1202, and input interface 1203 and output interface 1204 can be implemented on separate chips or circuit boards, and the embodiments of this application do not limit this.

[0119] Those skilled in the art will understand that the structure shown above does not constitute a limitation on the vehicle controller 1200, and may include more or fewer components than shown, or combine certain components, or use different component arrangements.

[0120] In an exemplary embodiment, a chip is also provided, the chip including programmable logic circuitry and / or program instructions, which, when the chip is run on the vehicle controller 1200, is used to implement the battery control method provided in the method embodiments of this application.

[0121] In an exemplary embodiment, a vehicle is also provided, the vehicle including an on-board controller for executing the battery control method provided in the method embodiments of this application.

[0122] In an exemplary embodiment, a computer-readable storage medium is also provided, which stores at least one program that is loaded and executed by a processor to implement the battery control method provided in the method embodiments of this application.

[0123] In an exemplary embodiment, a computer program product is also provided, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the battery control method provided in the method embodiments of this application.

[0124] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware or by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

[0125] Those skilled in the art will recognize that the functions described in the embodiments of this application in one or more of the above examples can be implemented using hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable storage medium or transmitted as one or more instructions or code on a computer-readable storage medium. Computer-readable storage media include computer storage media and communication media, wherein communication media include any medium that facilitates the transmission of a computer program from one place to another. Storage media can be any available medium accessible to a general-purpose or special-purpose computer.

[0126] The above are merely optional embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery control method, characterized in that, The method includes: The temperature rise coefficient of the power battery is obtained, which reflects the rate of temperature increase of the power battery under heating and self-heating conditions. The maximum discharge power is determined based on the temperature rise coefficient. The maximum discharge power is determined based on the discharge power of the power battery under the target temperature rise path. The target temperature rise path is the path of the power battery from the current temperature to the target temperature under the temperature rise coefficient. The target temperature is the temperature at which the basic allowable power of the power battery under the target state of charge (SOC) meets the power threshold. The target allowable power is determined based on the maximum discharge power, and the target allowable power is used to limit the output power of the power battery.

2. The method according to claim 1, characterized in that, The maximum discharge power is determined based on the target current, which is the current at which the power battery discharges according to the target duration corresponding to the target temperature rise path, and the target duration is the time it takes for the power battery to rise from the current temperature to the target temperature under the temperature rise coefficient.

3. The method according to claim 2, characterized in that, The step of determining the maximum discharge power based on the temperature rise coefficient includes: Based on the correlation between the SOC, temperature and basic allowable power of the power battery, the target temperature corresponding to the target SOC of the power battery is determined. Determine a first difference between the target temperature and the current temperature of the power battery; The target duration is obtained by determining the quotient of the first difference and the temperature rise coefficient; The maximum discharge power is determined based on the target duration.

4. The method according to claim 3, characterized in that, Determining the maximum discharge power based on the target duration includes: Determine the current capacity of the power battery based on its current state of charge (SOC). The target current is determined based on the quotient of the current capacity and the target duration; The maximum discharge power is determined by multiplying the target current by the current voltage of the power battery.

5. The method according to any one of claims 1 to 4, characterized in that, Determining the target allowable power based on the maximum discharge power includes: The basic allowable power of the power battery is determined based on its current temperature and current state of charge (SOC). The basic allowable power is adjusted based on the difference between the actual output power of the power battery and the maximum discharge power to obtain the adjusted allowable power; The target allowable power is determined based on the adjusted allowable power.

6. The method according to claim 5, characterized in that, The step of adjusting the basic allowable power based on the difference between the actual output power of the power battery and the maximum discharge power to obtain the adjusted allowable power includes: Determine a second difference between the actual output power and the maximum discharge power; The power derating amount is determined based on the second difference; The adjusted allowable power is determined based on the difference between the basic allowable power and the power derating.

7. The method according to claim 6, characterized in that, The step of determining the power derating based on the second difference includes: The first value is determined by multiplying the second difference by the first coefficient; The second value is determined by the product of the integral of the second difference over time and the second coefficient; The power derating amount is determined based on the sum of the first value and the second value.

8. The method according to claim 5, characterized in that, Determining the target allowable power based on the adjusted allowable power includes: Determine the maximum value between the adjusted allowable power and the preset allowable power; The target allowable power is determined based on the minimum value between the maximum value and the basic allowable power.

9. The method according to claim 5, characterized in that, The method further includes: The actual output power of the power battery during the first time period is obtained by low-pass filtering.

10. The method according to any one of claims 1 to 4, characterized in that, The process of obtaining the temperature rise coefficient of the power battery includes: The thermal management heat exchange capacity of the power battery is obtained, and the thermal management heat exchange capacity is used to reflect the power for heating or dissipating heat from the power battery. The self-heating capacity of the power battery is obtained, and the self-heating capacity is used to reflect the ability of the power battery to convert electrical energy into heat energy during operation. The temperature rise rate is determined based on the heat exchange capacity of the thermal management system and the self-heating capacity of the battery. The temperature rise coefficient is determined based on the temperature rise rate.

11. The method according to claim 10, characterized in that, Determining the temperature rise coefficient based on the temperature rise rate includes: The temperature rise rate determined within the second time period is low-pass filtered to obtain the temperature rise coefficient.

12. A battery control device, characterized in that, The device includes: The acquisition module is used to acquire the temperature rise coefficient of the power battery, which reflects the rate of temperature increase of the power battery under heating and self-heating conditions. The determination module is used to determine the maximum discharge power based on the temperature rise coefficient. The maximum discharge power is determined based on the discharge power of the power battery under the target temperature rise path. The target temperature rise path is the path of the power battery from the current temperature to the target temperature under the temperature rise coefficient. The target temperature is the temperature at which the basic allowable power of the power battery under the target SOC meets the power threshold. The determining module is further configured to determine a target allowable power based on the maximum discharge power, wherein the target allowable power is used to limit the output power of the power battery.

13. A vehicle-mounted controller, characterized in that, The vehicle controller includes a processor and a memory, wherein the memory stores at least one program; the processor is used to execute the at least one program in the memory to implement the battery control method as described in any one of claims 1 to 11.

14. A vehicle, characterized in that, The vehicle includes an on-board controller for performing the battery control method as described in any one of claims 1 to 11.

15. A computer-readable storage medium, characterized in that, The readable storage medium stores at least one program segment, which is loaded and executed by a processor to implement the battery control method as described in any one of claims 1 to 11.

16. A computer program product, characterized in that, The computer program product includes computer instructions stored in a computer-readable storage medium, a processor of a computer device reading the computer instructions from the computer-readable storage medium, and the processor executing the computer instructions to cause the computer device to perform the battery control method as described in any one of claims 1 to 11.

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