Battery power correction method, device, vehicle and computer readable storage medium

Abstract

The application provides a battery power correction method and device, a vehicle and a computer readable storage medium, and relates to the technical field of vehicles. The method comprises the following steps: when a correction condition of a remaining power of a battery pack is met, it is judged whether a power-off event of the vehicle is triggered; if yes, a depolarization operation of the battery pack is performed; in the case that the depolarization of the battery pack is completed, a voltage extreme value in voltages of all single batteries of the battery pack is obtained; and the remaining power of the battery pack is corrected according to the voltage extreme value. The application can realize active correction of the SOC of the battery pack of the vehicle, and is beneficial to improving the accuracy of SOC estimation.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and more specifically, to a battery charge correction method, apparatus, vehicle, and computer-readable storage medium in the field of vehicle technology. Background Technology

[0002] Currently, the calibration strategy for the remaining battery charge (SOC) in battery management systems (BMS) mainly calibrates the battery's SOC through specific external conditions or events. Although this strategy is effective in some simple scenarios, it suffers from problems such as high dependence, uncertain calibration timing, and error accumulation after long-term use, and cannot provide accurate SOC estimates. Summary of the Invention

[0003] This application provides a battery charge correction method, apparatus, vehicle, and computer-readable storage medium. This application realizes active correction of the State of Charge (SOC) of the vehicle battery pack, which helps to improve the accuracy of SOC estimation.

[0004] In a first aspect, a battery power correction method is provided, the battery power correction method comprising: when the correction conditions for the remaining power of the battery pack are met, determining whether a power-down event of the vehicle is triggered; if so, performing a depolarization operation of the battery pack; when the battery pack depolarization is completed, obtaining the voltage extreme value among the voltages of all individual cells in the battery pack; and correcting the remaining power of the battery pack according to the voltage extreme value.

[0005] Based on the above technical solution, this application embodiment adopts a technical solution that determines whether a vehicle power-off event is triggered when the correction condition for the remaining charge of the battery pack is met. If the vehicle power-off event is triggered, the depolarization operation of the battery pack is performed. After the battery pack depolarization is completed, the remaining charge of the battery pack is corrected according to the voltage extreme value among the voltages of all individual cells in the battery pack. This achieves the proactive correction of the battery pack's SOC when the need for SOC correction is detected, during the period when the user stops using the vehicle. This solves the problems of uncertain SOC calibration timing and error accumulation after long-term use in traditional passive calibration strategies. It not only improves the frequency and quality of SOC calibration but also improves the accuracy of SOC estimation.

[0006] In one possible implementation, the voltage extremes include a maximum single-cell voltage and a minimum single-cell voltage. Correcting the remaining capacity of the battery pack based on the voltage extremes includes: querying a first mapping table between open-circuit voltage and a first preset remaining capacity based on the maximum single-cell voltage to obtain a first capacity; querying the first mapping table based on the minimum single-cell voltage to obtain a second capacity; and correcting the remaining capacity of the battery pack based on the first capacity and the second capacity. By using the maximum and minimum single-cell voltages after battery pack depolarization is completed to correct the battery pack's SOC, the accuracy of SOC estimation, system safety and reliability can be significantly improved, energy management can be optimized, and user experience can be enhanced.

[0007] In one possible implementation, correcting the remaining power of the battery pack based on the first power level and the second power level includes: querying a second mapping relationship based on extreme power levels to obtain a target remaining power level; wherein the extreme power level includes the first power level and the second power level, the second mapping relationship includes multiple preset extreme power levels and each of the multiple preset extreme power levels corresponds to a second preset remaining power level; and correcting the remaining power of the battery pack to the target remaining power level.

[0008] In one possible implementation, obtaining the first energy level by querying a first mapping table of open-circuit voltage and first preset remaining energy level based on the maximum single-cell voltage includes: if the first mapping table includes the maximum single-cell voltage, determining the first preset remaining energy level corresponding to the open-circuit voltage that is the same as the maximum single-cell voltage in the first mapping table as the first energy level; if the first mapping table does not include the maximum single-cell voltage, determining the first energy level based on the voltage value and difference algorithm in the first mapping table.

[0009] In one possible implementation, before performing the depolarization operation of the battery pack, the battery power correction method further includes: maintaining the connection between the battery pack and the vehicle load. This ensures that after a power-down event is triggered, the connection between the battery pack and the vehicle load is not immediately disconnected. Instead, the switching module between the battery pack and the vehicle load is closed to maintain the connection, allowing the battery pack to discharge with a small current until depolarization is complete. This shortens the time the battery management system spends waiting to correct the State of Charge (SOC), facilitating faster SOC correction. After correcting the remaining battery power based on the voltage extreme value, the battery power correction method further includes: disconnecting the connection between the battery pack and the vehicle load.

[0010] In one possible implementation, the battery power correction method further includes: obtaining the cumulative discharge amount of the battery pack while maintaining the connection between the battery pack and the vehicle load; and determining that the battery pack depolarization is complete if the cumulative discharge amount is greater than or equal to a first threshold.

[0011] In one possible implementation, before determining whether a vehicle power-down event is triggered when the correction condition for the remaining battery charge of the battery pack is met, the battery charge correction method further includes: obtaining the cumulative charge and discharge amount of the battery pack; if the cumulative charge and discharge amount is greater than a second threshold, determining whether the difference between the remaining battery charge of the battery pack at any adjacent time is less than or equal to a third threshold; if yes, determining that the correction condition is met; if no, determining that the correction condition is not met.

[0012] Secondly, a battery power correction device is provided, the battery power correction device comprising:

[0013] The event judgment module is used to determine whether the vehicle power-off event has been triggered when the correction condition of the remaining battery power is met.

[0014] The battery control module is used to perform a depolarization operation of the battery pack when the power-down event is triggered.

[0015] The voltage acquisition module is used to acquire the voltage extreme value among all the individual cells of the battery pack after the battery pack depolarization is completed.

[0016] A power correction module is used to correct the remaining power of the battery pack based on the voltage extreme value.

[0017] In one possible implementation, the voltage extremes include the maximum single-cell voltage and the minimum single-cell voltage, and the charge correction module includes:

[0018] The first query unit is used to query a first mapping table between the open-circuit voltage and the first preset remaining power based on the maximum single-unit voltage to obtain the first power.

[0019] The second query unit is used to query the first mapping table based on the minimum single-unit voltage to obtain the second charge level;

[0020] The correction unit is used to correct the remaining power of the battery pack based on the first power level and the second power level.

[0021] In one possible implementation, the correction unit is specifically used to query a second mapping relationship based on the extreme power level to obtain the target remaining power level; wherein the extreme power level includes the first power level and the second power level, the second mapping relationship includes multiple preset extreme power levels and each of the multiple preset extreme power levels corresponds to a second preset remaining power level; and the remaining power level of the battery pack is corrected to the target remaining power level.

[0022] In one possible implementation, the first query unit is specifically used to determine the first preset remaining power corresponding to the open circuit voltage that is the same as the maximum single-cell voltage in the first mapping table as the first power when the first mapping table includes the maximum single-cell voltage; and to determine the first power according to the voltage value and difference algorithm in the first mapping table when the first mapping table does not include the maximum single-cell voltage.

[0023] In one possible implementation, the battery power correction device includes:

[0024] The device control unit is used to maintain the connection between the battery pack and the vehicle load before the battery control module performs the depolarization operation of the battery pack;

[0025] The device control unit is further configured to disconnect the battery pack from the vehicle load after the power correction module corrects the remaining power of the battery pack according to the voltage extreme value.

[0026] In one possible implementation, the battery power correction device includes:

[0027] The polarization determination unit is used to obtain the cumulative discharge amount of the battery pack while maintaining the connection between the battery pack and the vehicle load; and to determine that the depolarization of the battery pack is completed if the cumulative discharge amount is greater than or equal to a first threshold.

[0028] In one possible implementation, the event judgment module is further configured to obtain the cumulative charge and discharge amount of the battery pack; if the cumulative charge and discharge amount is greater than a second threshold, determine whether the difference between the remaining charge of the battery pack at any adjacent time is less than or equal to a third threshold; if yes, determine that the correction condition is met; if no, determine that the correction condition is not met.

[0029] Thirdly, a vehicle is provided, including a memory and a processor. The memory is used to store executable program code, and the processor is used to call and run the executable program code from the memory, causing the vehicle to perform the battery power correction method in the first aspect or any possible implementation thereof.

[0030] Fourthly, a computer program product is provided, comprising: computer program code, which, when run on a computer, causes the computer to execute the battery power correction method in the first aspect or any possible implementation thereof.

[0031] Fifthly, a computer-readable storage medium is provided that stores computer program code, which, when executed on a computer, causes the computer to perform the battery power correction method of the first aspect or any possible implementation thereof. Attached Figure Description

[0032] Figure 1 A schematic flowchart of a battery power correction method provided in an embodiment of this application is shown;

[0033] Figure 2 A schematic diagram of the OCV-SOC curve is shown;

[0034] Figure 3 A schematic diagram showing the connection between the battery pack and the vehicle load is shown;

[0035] Figure 4 This paper shows a schematic diagram of the structure of a battery power correction device provided in an embodiment of this application;

[0036] Figure 5 A schematic diagram of the structure of a vehicle provided in an embodiment of this application is shown. Detailed Implementation

[0037] The technical solutions in this application will be clearly and thoroughly described below with reference to the accompanying drawings. In the description of the embodiments of this application, unless otherwise stated, " / " means "or," for example, A / B can mean A or B. "And / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, in the description of the embodiments of this application, "multiple" refers to two or more than two.

[0038] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0039] Currently, the battery management system (BMS) primarily uses specific external conditions or events to calibrate the battery's State of Charge (SOC), a passive calibration strategy. While effective in some simple scenarios, this approach suffers from high dependency, uncertain calibration timing, and error accumulation over long-term use, ultimately failing to provide accurate SOC estimates. SOC refers to the ratio of the battery's current remaining charge to its fully charged state, typically expressed as a percentage. In the automotive field, SOC informs the driver of the battery's remaining charge, aiding in trip planning.

[0040] To address the aforementioned issues, this application provides a battery charge correction method, apparatus, vehicle, and computer-readable storage medium. This application achieves active correction of the State of Charge (SOC) of the vehicle battery pack through proactive intervention, solving problems such as uncertain SOC calibration timing and error accumulation after long-term use in traditional passive calibration strategies. This not only improves the frequency and quality of SOC calibration but also enhances the accuracy of SOC estimation.

[0041] The following is an embodiment of a battery power correction method provided in this application specification.

[0042] Figure 1 A schematic flowchart of a battery power correction method provided in an embodiment of this application is shown, such as... Figure 1 As shown in the embodiments of this application, the battery power correction method is applied to the battery management system of a vehicle. The battery management system is an electronic control system used to monitor and manage the operating status of the battery pack and provide safety protection for the battery to ensure it operates in optimal condition, extend battery life, and guarantee the safe operation of the vehicle. The functions of this battery management system include battery status monitoring (such as voltage, current, and temperature), fault diagnosis, and thermal management.

[0043] The above-mentioned battery power correction methods include the following schemes:

[0044] S110: When the correction condition for the remaining charge of the battery pack is met, determine whether the vehicle power-off event has been triggered.

[0045] In an exemplary embodiment, for new energy vehicles (e.g., hybrid electric vehicles, electric vehicles), the battery pack generally refers to the vehicle's power battery; for gasoline vehicles, the battery pack generally refers to the storage battery. If the battery management system determines, based on the battery pack's charging and discharging status and its previous remaining SOC, that the conditions for correcting the battery pack's current SOC are met, then it considers that the battery pack's current SOC has not been corrected and needs to be corrected.

[0046] To ensure that the battery pack's State of Charge (SOC) is accurate at any given time and does not fluctuate suddenly, SOC correction is generally performed after the user has used the vehicle. When the remaining battery charge correction condition is met, the system checks whether a power-down event has been triggered. Specifically, this determines whether the user intends to stop using the vehicle. If a power-down event is triggered, it indicates the user's intention to stop using the vehicle. The method for determining whether a power-down event has been triggered depends on the vehicle's actual power-down control strategy. Example 1: Class A vehicles are equipped with a power-down switch (e.g., a physical power-down switch and / or a virtual power-down switch). When the vehicle is stationary, if the user triggers the power-down switch, the battery management system receives the power-down command from the switch and determines that a power-down event has been triggered. Example 2: Class B vehicles are not equipped with a power-down switch. When the vehicle is stationary, the battery management system receives a locking completion command from the vehicle locking system and determines that a power-down event has been triggered.

[0047] S120: When a power-down event of the vehicle is triggered, perform a depolarization operation on the battery pack.

[0048] Failure to depolarize the battery pack before correcting the current State of Charge (SOC) can lead to a series of problems that affect the accuracy of the battery management system and the lifespan of the battery pack. Negative impacts of not depolarizing the battery pack include: increased SOC estimation errors, reduced accuracy of battery health assessments, decreased system safety and reliability, shortened battery pack lifespan, and more.

[0049] To avoid the potential negative impact of not depolarizing the battery pack, after determining that a power-off event has been triggered (the user stops using the vehicle), the battery management system proactively prepares for the correction of the current SOC. That is, instead of immediately correcting the current SOC of the battery pack, it performs a depolarization operation on the battery pack.

[0050] Performing a battery pack depolarization operation can include: disconnecting the battery pack from the vehicle load, and then depolarizing the battery pack by allowing it to stand still; after disconnecting the battery pack from the vehicle load, the user can visually see that the vehicle is powered down (for example, the user sees that the dashboard, various displays, etc., in the car are all turned off). Performing a battery pack depolarization operation can also include: although the user triggers a power-down event, the vehicle does not immediately disconnect the battery pack from the vehicle load, but instead maintains the connection between the battery pack and the vehicle load, and then depolarizes the battery pack by discharging a small current. In this depolarization method, after the user triggers the vehicle's power-down event, the vehicle pretends to be powered down, and the user can visually confirm that the vehicle is powered down. However, in reality, the battery management system delays its response to the power-down event trigger command and continues to maintain the connection between the battery pack and the vehicle's load. Only after the battery pack depolarization is completed and the subsequent SOC correction operation is finished will the system respond to the power-down event trigger command, thereby disconnecting the connection between the battery pack and the vehicle's load, meaning the vehicle is truly powered down.

[0051] S130: After the battery pack depolarization is completed, obtain the voltage extreme value among the voltages of all individual cells in the battery pack.

[0052] The battery pack consists of multiple individual cells, which are electrically connected in series, parallel, or a combination thereof. All individual cells have identical electrical properties (voltage, current, capacity). After detecting that the battery pack depolarization is complete, the battery management system actively performs a correction operation on the current state of charge (SOC) of the battery pack. The correction process includes: obtaining the voltage extreme values ​​among the voltages of all individual cells in the battery pack. For example, if the battery pack contains 1000 individual cells, 1000 voltages can be obtained. By comparing the magnitudes of these 1000 voltages, the voltage extreme values ​​can be obtained, including the maximum and / or minimum values ​​among these 1000 voltages.

[0053] S140: Corrects the remaining battery pack capacity based on voltage extreme values.

[0054] After obtaining the voltage extreme values ​​among all individual battery cells, the target remaining capacity of the battery pack, i.e. the target SOC, is estimated based on the voltage extreme values. The current SOC is then corrected to the target SOC, i.e., the current SOC = the target SOC, thereby achieving the correction of the current SOC.

[0055] This application embodiment employs a technical solution that determines whether a vehicle power-off event has been triggered when the remaining battery pack charge correction condition is met. If the vehicle power-off event is triggered, a battery pack depolarization operation is performed. After the battery pack depolarization is completed, the remaining battery pack charge is corrected based on the voltage extreme values ​​among the voltages of all individual cells in the battery pack. This achieves proactive correction of the battery pack's SOC while the user is not using the vehicle when a correction is detected. This solves the problems of uncertain SOC calibration timing and error accumulation after long-term use in traditional passive calibration strategies. It not only improves the frequency and quality of SOC calibration but also enhances the accuracy of SOC estimation.

[0056] The following are Figure 1 The specific implementation methods of each step in the illustrated embodiment will be explained below:

[0057] In one possible implementation, voltage extremes include the maximum cell voltage (maximum) and the minimum cell voltage (minimum). The above-mentioned correction of the battery pack's remaining capacity based on voltage extremes includes the following steps:

[0058] The first energy level is obtained by querying the first mapping table between the open-circuit voltage and the first preset remaining energy level based on the maximum single-cell voltage;

[0059] The second charge level is obtained by querying the first mapping table based on the minimum unit voltage;

[0060] Adjust the remaining battery power based on the first and second battery levels.

[0061] When there is no vehicle load at the two ends of the battery pack, the voltage at the two ends of the battery pack is called the open circuit voltage (OCV). The first mapping table between the open circuit voltage and the first preset remaining power is also called the OCV-SOC mapping table. The OCV-SOC mapping table is obtained by the OCV-SOC curve. Figure 2 A schematic diagram of the OCV-SOC curve is shown. The OCV-SOC curve is as follows: Figure 2 As shown in Table 1, the OCV-SOC mapping table can be interpreted as the first preset remaining power.

[0062] Table 1

[0063]

[0064]

[0065] After obtaining the maximum cell voltage, the SOC value corresponding to the maximum cell voltage can be found in Table 1, which is the first capacity. Similarly, after obtaining the minimum cell voltage, the SOC value corresponding to the minimum cell voltage can be found in Table 1, which is the second capacity. Then, based on the first and second capacity values, the target SOC of the battery pack is estimated, and the current SOC is corrected to the target SOC.

[0066] By correcting the state of charge (SOC) of the battery pack using the maximum and minimum single-cell voltages when battery pack depolarization is complete, the accuracy of SOC estimation, system safety and reliability can be significantly improved, energy management can be optimized, and user experience can be enhanced.

[0067] In one possible implementation, the aforementioned first and second charge levels, along with the steps to correct the remaining charge of the battery pack, include:

[0068] The target remaining power is obtained by querying the second mapping relationship based on the extreme power value; wherein, the extreme power value includes the first power value and the second power value, and the second mapping relationship includes multiple preset extreme power values ​​and the second preset remaining power value corresponding to each of the multiple preset extreme power values;

[0069] Adjust the remaining battery power of the battery pack to the target remaining battery power.

[0070] Table 2

[0071]

[0072] The second mapping relationship is shown in Table 2. Each preset extreme energy level in Table 2 includes a first preset energy level corresponding to the maximum single-cell voltage and a second preset energy level corresponding to the minimum single-cell voltage. A1max, A2max, ... can all be understood as the first preset energy level, and A1min, A2min, ... can all be understood as the second preset energy level. For example, if the first energy level is A2max and the second energy level is A2min, then the target SOC is A2m, which means the current SOC is corrected to A2m. By querying the second mapping relationship through extreme energy levels, the target remaining energy level can be obtained, which can improve the SOC correction efficiency.

[0073] In one possible implementation, the aforementioned first and second charge levels, along with the steps to correct the remaining charge of the battery pack, include:

[0074] The average value method is used to take the average value of the first and second battery levels as the target SOC. The target SOC is calculated as (first battery level + second battery level) / 2. Then, the current SOC is adjusted to the target SOC.

[0075] In one possible implementation, the aforementioned first and second charge levels, along with the steps to correct the remaining charge of the battery pack, include:

[0076] According to the weighted average method, the first and second energy levels are weighted and averaged to obtain the target SOC, i.e., target SOC = w1 × first energy level + w2 × second energy level. Then, the current SOC is corrected to the target SOC. Here, w1 is the weight corresponding to the maximum single-cell voltage, w2 is the weight corresponding to the minimum single-cell voltage, and w1 + w2 = 1.

[0077] In one possible implementation, obtaining the first energy level by querying a first mapping table between the open-circuit voltage and the first preset remaining energy level based on the maximum single-cell voltage includes the following steps:

[0078] If the first mapping table includes the maximum single-cell voltage, the first preset remaining charge corresponding to the open-circuit voltage that is the same as the maximum single-cell voltage in the first mapping table is determined as the first charge.

[0079] If the first mapping table does not include the maximum single-cell voltage, the first charge is determined based on the voltage values ​​in the first mapping table and the difference algorithm.

[0080] Considering whether the first mapping table includes the maximum cell voltage or not, the method for determining the first charge level differs depending on whether the maximum cell voltage is included. If the first mapping table includes the maximum cell voltage, the first charge level can be directly obtained by looking up the table. Specifically, the open-circuit voltage that matches the maximum cell voltage in the first mapping table is retrieved, and the first preset remaining charge level corresponding to the retrieved open-circuit voltage is the first charge level. For example, if the maximum cell voltage is 3.64V, then the first charge level is 50%.

[0081] If the first mapping table does not include the maximum single-cell voltage, it means that the first charge cannot be directly obtained by looking up the table. Therefore, the first charge is calculated using the voltage values ​​in the first mapping table and a difference algorithm. This allows for accurate calculation of the first charge even when the maximum single-cell voltage is not included in the first mapping table. For example, if the maximum single-cell voltage is 3.70V, which does not exist in Table 1, the first charge corresponding to the maximum single-cell voltage is calculated using a linear difference formula. The linear difference formula is as follows:

[0082]

[0083] For example, SOC = 3.70V, OCV1 = 3.64V, SOC1 = 50%, OCV2 = 3.74V, SOC2 = 60%, SOC 插 =56%, meaning the first charge corresponding to the maximum single-unit voltage is 56%.

[0084] In one possible implementation, the above-mentioned method of querying the first mapping table based on the minimum single-cell voltage to obtain the second charge includes the following steps:

[0085] If the first mapping table includes the minimum unit voltage, the first preset remaining charge corresponding to the open circuit voltage that is the same as the minimum unit voltage in the first mapping table is determined as the second charge.

[0086] If the minimum unit voltage is not included in the first mapping table, the second charge is determined based on the voltage values ​​in the first mapping table and the difference algorithm.

[0087] The method for determining the second charge level is the same as the method for determining the first charge level when the first mapping table includes the minimum single-cell voltage and does not include the minimum single-cell voltage. This will not be repeated in the embodiments of this application.

[0088] One possible implementation is, such as Figure 3 As shown, Figure 3 The diagram illustrates the connection between a battery pack and a vehicle load. D represents the battery pack, R represents the vehicle load, and K represents the switching module. The switching module connects the battery pack and the vehicle load. When the switching module is closed, the connection between the battery pack and the vehicle load is established, forming a circuit. When the switching module is open, the connection between the battery pack and the vehicle load is broken, and a circuit cannot be formed. The switching module can be a relay or a switching circuit composed of transistors, MOSFETs, or other switching devices.

[0089] Before performing the depolarization operation of the battery pack, the battery capacity correction method further includes the following steps:

[0090] Maintain the connection between the battery pack and the vehicle load.

[0091] Considering the relatively long depolarization time during resting mode, the battery management system (BMS) spends a considerable amount of time waiting to correct the State of Charge (SOC), making it impossible to complete SOC correction quickly. Therefore, to complete SOC correction more quickly, after a power-down event is triggered, the connection between the battery pack and the vehicle load is not immediately disconnected. Instead, the switching module between the battery pack and the vehicle load is closed to maintain the connection, allowing the battery pack to discharge with a small current until depolarization is complete. This shortens the long waiting time for SOC correction by the BMS, facilitating faster SOC correction. Figure 3 As shown, Figure 3 The switching module in the battery pack is a relay. During battery pack depolarization, the relay is always in a closed state, meaning that the battery pack is always connected to the vehicle load.

[0092] After correcting the remaining battery capacity based on the voltage extreme value, the battery capacity correction method further includes the following steps:

[0093] Disconnect the battery pack from the vehicle load.

[0094] Because the relay remains closed during battery pack depolarization and SOC correction, the vehicle is not actually powered off. Once the battery pack's current SOC correction is complete, the control switch module disconnects, breaking the connection between the battery pack and the vehicle load, thus achieving true vehicle power-off control. Figure 3 As shown, Figure 3 The switching module in the battery pack is a relay. After the current SOC of the battery pack is corrected, the relay is in the off state, and the connection between the battery pack and the vehicle load is disconnected.

[0095] In one possible implementation, the above battery power correction method further includes the following steps:

[0096] While maintaining the connection between the battery pack and the vehicle load, the cumulative discharge of the battery pack is obtained;

[0097] If the cumulative discharge is greater than or equal to the first threshold, the battery pack depolarization is determined to be complete.

[0098] Since the battery pack depolarization operation is performed while maintaining the connection between the battery pack and the vehicle load and controlling the battery pack to discharge with a small current, the determination of whether the battery pack depolarization is complete is specifically based on obtaining the cumulative discharge amount of the battery pack while maintaining the connection with the vehicle load. The cumulative discharge amount is the sum of the discharge amounts during the battery pack depolarization process. The relationship between the cumulative discharge amount and a first threshold (i.e., the discharge amount threshold) is used to determine whether the battery pack depolarization is complete. If the cumulative discharge amount is greater than or equal to the first threshold, it indicates that the battery pack depolarization is complete; if the cumulative discharge amount is less than the first threshold, it indicates that the battery pack depolarization is not complete, and the process returns to the step of obtaining the cumulative discharge amount of the battery pack until the relationship between the cumulative discharge amount and the first threshold determines that the battery pack depolarization is complete, thereby executing the subsequent SOC correction operation, which is to execute the step of obtaining the voltage extreme value among the voltages of all individual cells in the battery pack.

[0099] In one possible implementation, before determining whether a vehicle power-down event has been triggered when the correction condition for the remaining battery charge of the battery pack is met, the battery charge correction method further includes:

[0100] Obtain the cumulative charge and discharge amount of the battery pack;

[0101] If the cumulative charge and discharge amount is greater than the second threshold, determine whether the difference between the remaining charge of the battery pack at any adjacent time is less than or equal to the third threshold.

[0102] If so, the correction condition is satisfied;

[0103] If not, the correction condition is not met.

[0104] The process for determining whether the SOC correction conditions are met includes the following steps: Before each SOC correction, the battery pack's charge and discharge amounts are accumulated to obtain the cumulative charge / discharge amount, i.e., cumulative charge / discharge amount = charge amount + discharge amount. After obtaining the cumulative charge / discharge amount, the relationship between the cumulative charge / discharge amount and a second threshold is determined. The second threshold is N times the rated capacity of the battery pack, where N is a positive integer greater than or equal to 2. If the cumulative charge / discharge amount is greater than the second threshold, it is initially considered that the battery pack's SOC needs correction, and then it is further determined whether the battery pack's SOC has been corrected in the past. Determining whether the battery pack's State of Charge (SOC) has been previously corrected includes, if the cumulative charge / discharge amount exceeds a second threshold, determining whether the difference between the remaining battery charge at any adjacent time point is less than or equal to a third threshold. For example, if the difference between the SOC at time t (the current time) and the SOC at time t-1 is greater than the third threshold, it indicates that the battery pack's SOC has been previously corrected, and subsequent correction operations are unnecessary. If the difference between the SOC at time t (the current time) and the SOC at time t-1 is less than or equal to the third threshold, it indicates that the battery pack's SOC has not been previously corrected, and subsequent correction operations are required, further determining that the battery pack's SOC needs correction. Once the current SOC of the battery pack has been corrected, the cumulative charge / discharge amount of the battery pack is reset to zero and begins accumulating again from zero.

[0105] By determining whether the difference between the remaining charge and discharge capacity of the battery pack at any adjacent time is less than or equal to the third threshold when the cumulative charge and discharge capacity is greater than the second threshold, the accuracy of determining whether the SOC correction of the battery pack is required is improved, and the situation of correcting the SOC when no correction is needed is avoided.

[0106] The following is an embodiment of a battery power correction method provided in this application specification.

[0107] This application specification provides a battery capacity correction method including the following scheme:

[0108] S210: Obtain the cumulative charge and discharge amount of the battery pack; before each SOC correction, the charge and discharge amount of the battery pack will be accumulated to obtain the cumulative charge and discharge amount, that is, cumulative charge and discharge amount = charge amount + discharge amount.

[0109] S211: Determine whether the cumulative charge and discharge amount is greater than the second threshold. If yes, it indicates that the SOC of the battery pack needs to be corrected, and execute S212; otherwise, execute S210.

[0110] S212: Determine whether the difference between the SOC of the battery pack at any adjacent time is less than or equal to the third threshold. If yes, it means that the SOC of the battery pack has not been corrected before, and it also means that the SOC of the battery pack needs to be corrected. Execute S213. If no, do not perform the SOC correction operation.

[0111] S213: Determine whether the vehicle power-off event has been triggered. If yes, it indicates that the user intends to stop using the vehicle, and execute S214; otherwise, execute S212.

[0112] S214: Controls the closing of the switching module between the battery pack and the vehicle load to maintain the connection between the battery pack and the vehicle load, and performs a depolarization operation on the battery pack. Specifically, while maintaining the connection between the battery pack and the vehicle load, it controls the battery pack to discharge a small current to perform depolarization.

[0113] S215: Obtain the cumulative discharge amount of the battery pack.

[0114] S216: Determine whether the cumulative discharge amount is greater than or equal to the first threshold to determine whether the battery pack depolarization is complete. If yes, proceed to S217; otherwise, proceed to S215.

[0115] S217: Obtain the maximum and minimum cell voltages (i.e., minimum values) among all the individual cells in the battery pack.

[0116] S218: The first energy level is obtained by querying a first mapping table of open-circuit voltage and first preset remaining energy level based on the maximum single-cell voltage, and the second energy level is obtained by querying the first mapping table based on the minimum single-cell voltage. Specifically, if the first mapping table includes the maximum single-cell voltage, the first preset remaining energy level corresponding to the open-circuit voltage in the first mapping table that is the same as the maximum single-cell voltage is determined as the first energy level; if the first mapping table does not include the maximum single-cell voltage, the first energy level is determined based on the voltage values ​​in the first mapping table and a difference algorithm. Similarly, if the first mapping table includes the minimum single-cell voltage, the first preset remaining energy level corresponding to the open-circuit voltage in the first mapping table that is the same as the minimum single-cell voltage is determined as the second energy level; if the first mapping table does not include the minimum single-cell voltage, the second energy level is determined based on the voltage values ​​in the first mapping table and a difference algorithm.

[0117] S219: The target SOC is obtained by querying the second mapping relationship based on the extreme power values. The extreme power values ​​include the first power value and the second power value. The second mapping relationship includes multiple preset extreme power values ​​and their corresponding second preset remaining power values. Furthermore, the average of the first and second power values ​​is used as the target SOC using the average method: Target SOC = (First Power Value + Second Power Value) / 2. The current SOC is then corrected to the target SOC. Alternatively, the target SOC is obtained by performing a weighted average calculation on the first and second power values ​​using the weighted average method: Target SOC = w1 × First Power Value + w2 × Second Power Value. The current SOC is then corrected to the target SOC. Here, w1 is the weight corresponding to the maximum single-unit voltage, w2 is the weight corresponding to the minimum single-unit voltage, and w1 + w2 = 1.

[0118] S220: Correct the current SOC of the battery pack to the target SOC, i.e., current SOC correction = target SOC.

[0119] S221: Controls the switching module between the battery pack and the vehicle load to disconnect the connection between the battery pack and the vehicle load, thereby achieving true power-off control of the vehicle.

[0120] S222: Exit the SOC correction process. The current SOC correction of the battery pack is now complete.

[0121] The battery power correction method provided in this application has the following technical effects:

[0122] 1. Actively correct the SOC of the battery pack, which means that it no longer relies solely on occasional calibration opportunities during vehicle use, but actively creates calibration conditions through certain mechanisms to ensure that the SOC of the battery pack can be maintained accurately even under adverse conditions.

[0123] 2. Improve the accuracy of SOC estimation. Discharging with a small current during the battery pack depolarization period can reduce the polarization effect inside the battery pack, so that the open circuit voltage can more accurately reflect the state of the battery pack, thereby improving the accuracy of SOC estimation.

[0124] 3. Reduce error accumulation. Long-term lack of calibration will lead to the accumulation of SOC estimation errors. However, the active calibration strategy can correct the error before it accumulates to a certain level, which can prevent the SOC deviation from being too large and affecting the user experience and battery life.

[0125] 4. Optimize the user experience. Users no longer need to worry about inaccurate SOC display due to prolonged lack of calibration conditions. This increases users' confidence in the status of the vehicle's battery pack and makes it easier for users to accurately estimate the vehicle's pure electric range through the SOC displayed on the vehicle's dashboard.

[0126] The following are embodiments of the apparatus described in this application, which can be used to execute the embodiments of the method described in this application. For details not disclosed in the apparatus embodiments of this application, please refer to the embodiments of the method described in this application.

[0127] Figure 4 A schematic diagram of a battery power correction device provided in an embodiment of this application is shown, as follows: Figure 4 As shown, the battery power correction device 400 includes:

[0128] The event judgment module 410 is used to determine whether the vehicle power-off event is triggered when the correction condition of the remaining power of the battery pack is met.

[0129] The battery control module 420 is used to perform a depolarization operation of the battery pack when the power-down event is triggered.

[0130] The voltage acquisition module 430 is used to acquire the voltage extreme value among the voltages of all individual cells in the battery pack after the battery pack depolarization is completed.

[0131] The power correction module 440 is used to correct the remaining power of the battery pack according to the voltage extreme value.

[0132] In one possible implementation, the voltage extremes include the maximum single-cell voltage and the minimum single-cell voltage, and the power correction module 440 includes:

[0133] The first query unit is used to query a first mapping table between the open-circuit voltage and the first preset remaining power based on the maximum single-unit voltage to obtain the first power.

[0134] The second query unit is used to query the first mapping table based on the minimum single-unit voltage to obtain the second charge level;

[0135] The correction unit is used to correct the remaining power of the battery pack based on the first power level and the second power level.

[0136] In one possible implementation, the correction unit is specifically used to query a second mapping relationship based on the extreme power level to obtain the target remaining power level; wherein the extreme power level includes the first power level and the second power level, the second mapping relationship includes multiple preset extreme power levels and each of the multiple preset extreme power levels corresponds to a second preset remaining power level; and the remaining power level of the battery pack is corrected to the target remaining power level.

[0137] In one possible implementation, the first query unit is specifically used to determine the first preset remaining power corresponding to the open circuit voltage that is the same as the maximum single-cell voltage in the first mapping table as the first power when the first mapping table includes the maximum single-cell voltage; and to determine the first power according to the voltage value and difference algorithm in the first mapping table when the first mapping table does not include the maximum single-cell voltage.

[0138] In one possible implementation, the battery power correction device 400 includes:

[0139] The device control unit is used to maintain the connection between the battery pack and the vehicle load before the battery control module 420 performs the depolarization operation of the battery pack;

[0140] The device control unit is further configured to disconnect the battery pack from the vehicle load after the power correction module 440 corrects the remaining power of the battery pack according to the voltage extreme value.

[0141] In one possible implementation, the battery power correction device 400 includes:

[0142] The polarization determination unit is used to obtain the cumulative discharge amount of the battery pack while maintaining the connection between the battery pack and the vehicle load; and to determine that the depolarization of the battery pack is completed if the cumulative discharge amount is greater than or equal to a first threshold.

[0143] In one possible implementation, the event judgment module 410 is further configured to obtain the cumulative charge and discharge amount of the battery pack; if the cumulative charge and discharge amount is greater than a second threshold, determine whether the difference between the remaining charge of the battery pack at any adjacent time is less than or equal to a third threshold; if yes, determine that the correction condition is met; if no, determine that the correction condition is not met.

[0144] It should be noted that the battery power correction device provided in the above embodiments is only illustrated by the division of the above functional modules when executing the battery power correction method. In actual 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 power correction device and the battery power correction method embodiments provided in the above embodiments belong to the same concept. Therefore, for details not disclosed in the device embodiments of this application, please refer to the embodiments of the battery power correction method described above in this application, which will not be repeated here.

[0145] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0146] Figure 5 This application provides a schematic diagram of the structure of a vehicle according to an embodiment of the present application. Figure 5 As shown, the vehicle 500 includes a memory 501 and a processor 502. The memory 501 stores executable program code 5011, and the processor 502 is used to call and execute the executable program code 5011 to perform a battery power correction method.

[0147] This embodiment can divide the vehicle into functional modules according to the above method example. For example, each function can be assigned to a separate module, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.

[0148] When each functional module is divided according to its corresponding function, the vehicle may include: an event judgment module, a battery control module, a voltage acquisition module, a power correction module, etc. It should be noted that all relevant content of each step involved in the above method embodiments can be referenced from the functional description of the corresponding functional module, and will not be repeated here.

[0149] The vehicle provided in this embodiment is used to execute the battery power correction method described above, and thus can achieve the same effect as the above implementation method.

[0150] When using integrated units, the vehicle may include a processing module and a storage module. The processing module is used to control and manage the vehicle's movements. The storage module is used to support the vehicle in executing relevant program code and data.

[0151] The processing module may be a processor or a controller, which can implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this application. The processor may also be a combination of functions that implement computing capabilities, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and microprocessors, etc., and the storage module may be a memory.

[0152] This embodiment also provides a computer-readable storage medium storing computer program code. When the computer program code is run on a computer, the computer executes the aforementioned method steps to implement a battery power correction method in the above embodiment.

[0153] This embodiment also provides a computer program product that, when run on a computer, causes the computer to perform the aforementioned related steps to implement a battery power correction method as described in the above embodiment.

[0154] In addition, the vehicle provided in the embodiments of this application may specifically be a chip, component or module. The vehicle may include a connected processor and a memory. The memory is used to store instructions. When the vehicle is running, the processor may call and execute the instructions to make the chip execute a battery power correction method in the above embodiments.

[0155] In this embodiment, the vehicle, computer-readable storage medium, computer program product, or chip are all used to execute the corresponding battery power correction method provided above. Therefore, the beneficial effects that can be achieved can be referred to the beneficial effects in the corresponding battery power correction method provided above, and will not be repeated here.

[0156] Through the above description of the embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual 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.

[0157] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0158] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions 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 scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A battery charge correction method, characterized in that, The battery power correction method includes: Obtain the cumulative charge and discharge amount of the battery pack; If the cumulative charge and discharge amount is greater than the second threshold, determine whether the difference between the remaining charge of the battery pack at any adjacent time is less than or equal to the third threshold. If so, the correction condition is satisfied; If not, it is determined that the correction conditions are not met; When the correction condition for the remaining charge of the battery pack is met, it is determined whether the vehicle power-down event has been triggered. Maintain the connection between the battery pack and the vehicle load; If so, perform the depolarization operation of the battery pack; Once the battery pack depolarization is complete, obtain the voltage extreme values ​​among the voltages of all individual cells in the battery pack. The remaining charge of the battery pack is corrected based on the voltage extreme value; Disconnect the battery pack from the vehicle load.

2. The battery charge correction method according to claim 1, characterized in that, The voltage extreme values ​​include the maximum single-cell voltage and the minimum single-cell voltage, and the step of correcting the remaining capacity of the battery pack based on the voltage extreme values ​​includes: The first energy level is obtained by querying the first mapping table between the open-circuit voltage and the first preset remaining energy level based on the maximum single-unit voltage; The second charge level is obtained by querying the first mapping table based on the minimum unit voltage; The remaining power of the battery pack is adjusted based on the first power level and the second power level.

3. The battery power correction method according to claim 2, characterized in that, The step of adjusting the remaining power of the battery pack based on the first power level and the second power level includes: The target remaining power is obtained by querying the second mapping relationship based on the extreme power value; wherein, the extreme power value includes the first power value and the second power value, and the second mapping relationship includes multiple preset extreme power values ​​and the second preset remaining power value corresponding to each of the multiple preset extreme power values; The remaining power of the battery pack is adjusted to the target remaining power.

4. The battery charge correction method according to claim 2, characterized in that, The step of querying the first mapping table between the open-circuit voltage and the first preset remaining power based on the maximum single-unit voltage to obtain the first power includes: If the first mapping table includes the maximum single-cell voltage, the first preset remaining charge corresponding to the open-circuit voltage that is the same as the maximum single-cell voltage in the first mapping table is determined as the first charge. If the first mapping table does not include the maximum single-unit voltage, the first charge is determined based on the voltage values ​​in the first mapping table and the difference algorithm.

5. The battery charge correction method according to claim 1, characterized in that, The battery power correction method further includes: While maintaining the connection between the battery pack and the vehicle load, the cumulative discharge amount of the battery pack is obtained; If the cumulative discharge is greater than or equal to the first threshold, it is determined that the battery pack depolarization is complete.

6. A battery power correction device, characterized in that, The battery power correction device includes: The event judgment module is used to determine whether the vehicle power-off event has been triggered when the correction condition of the remaining battery power is met. The battery control module is used to perform a depolarization operation of the battery pack when the power-down event is triggered. The voltage acquisition module is used to acquire the voltage extreme value among all the individual cells of the battery pack after the battery pack depolarization is completed. A power correction module is used to correct the remaining power of the battery pack according to the voltage extreme value; The device control unit is configured to maintain the connection between the battery pack and the vehicle load before the battery control module performs the depolarization operation of the battery pack; and to disconnect the connection between the battery pack and the vehicle load after the power correction module corrects the remaining power of the battery pack according to the voltage extreme value. The event judgment module is further configured to obtain the cumulative charge and discharge amount of the battery pack; if the cumulative charge and discharge amount is greater than the second threshold, determine whether the difference between the remaining power of the battery pack at any adjacent time is less than or equal to the third threshold; if yes, determine that the correction condition is met; if no, determine that the correction condition is not met.

7. A vehicle, characterized in that, The vehicles include: Memory, used to store executable program code; A processor is configured to call and run the executable program code from the memory, causing the vehicle to perform the battery power correction method as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed, implements the battery power correction method as described in any one of claims 1 to 5.

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