Battery power correction method, controller, battery management system, battery and vehicle
Patent Information
- Application Number
- CN202511547622.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-24
- Publication Date
- 2026-08-21
AI Technical Summary
以上方式均未考虑电池放电过程中电压值和电流值具有响应迟滞性，无法及时捕捉放电过程中真实的电压值和电流值，导致最终计算的SOC精度不足
[0037]A third aspect of this application provides a battery management system, including the controller described in the second aspect of this application.
Smart Images
Figure CN122607118A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery management technology, and in particular to a battery power correction method, controller, battery management system, battery, and vehicle. Background Technology
[0002] When a power battery is in operation and has its remaining State of Charge (SOC), if the user frequently fails to fully charge the battery or uses the vehicle continuously for extended periods, the calibrated SOC of the power battery will have a significant error, impacting the user experience. Current technologies typically correct the battery SOC using only the voltage and current values under stable conditions (such as the state of the battery after a certain period of inactivity), or only the instantaneous voltage and current values obtained during battery discharge. Neither of these methods considers the hysteresis of voltage and current values during battery discharge, failing to capture the true voltage and current values in a timely manner, resulting in insufficient accuracy in the final calculated SOC. Summary of the Invention
[0003] The embodiments of this application provide a battery power correction method, a controller, a battery management system, a battery, and a vehicle.
[0004] A first aspect of this application provides a battery power correction method, the method comprising:
[0005] Obtain the first voltage value and the first current value of the battery at the current moment when the battery is in a discharging state;
[0006] Calculate the second voltage value and the second current value of the battery based on the first voltage value and the first current value;
[0007] The battery charge correction value is determined based on the first voltage value, the first current value, the second voltage value, and the second current value;
[0008] The remaining battery capacity is corrected based on the power correction value.
[0009] In some embodiments, calculating the second voltage value and the second current value of the battery based on the first voltage value and the first current value of the battery includes:
[0010] The forgetting factor is determined based on the first temperature value of the battery;
[0011] The second voltage value is calculated based on the first voltage value and the forgetting factor;
[0012] The second current value is calculated based on the first current value and the forgetting factor.
[0013] In some embodiments, determining the battery charge correction value based on the first voltage value, the first current value, the second voltage value, and the second current value includes:
[0014] When the first temperature value is greater than or equal to the first temperature threshold:
[0015] The first target charge value is obtained by querying the constant current discharge curve based on the first voltage value, the first current value, the first temperature value, and the battery's state of health (SOH).
[0016] The second target charge value is obtained by querying the constant current discharge curve based on the second voltage value, the second current value, the first temperature value, and the battery's state of health (SOH).
[0017] A first correction condition is determined based on the first temperature value, the first target charge value, the first voltage value, and the first current value; a second correction condition is determined based on the first temperature value, the second target charge value, the second voltage value, and the second current value.
[0018] The power correction value is determined based on the first correction condition and the second correction condition.
[0019] In some embodiments, the first correction condition includes:
[0020] The first target power value is less than the first remaining power threshold, and the first current value is the maximum discharge pulse current value of the battery within the first time interval, and the first voltage value is greater than the difference between the voltage value and the average voltage value but less than a preset voltage difference.
[0021] The average voltage value is the average of the voltages of all cells in the battery.
[0022] In some embodiments, the second correction condition includes:
[0023] When the second target power value is less than the second remaining power threshold and the first temperature value is less than the second temperature threshold, the difference between the first current value and the second current value is greater than the first preset current value.
[0024] In some embodiments, determining the power correction value based on the first correction condition and the second correction condition includes:
[0025] If the first temperature value, the first target power value, the first voltage value, and the first current value satisfy the first correction condition, and the first temperature value, the second target power value, the second voltage value, and the second current value do not satisfy the second correction condition, the power correction value is the first target power value.
[0026] In some embodiments, determining the power correction value based on the first correction condition and the second correction condition includes:
[0027] If the first temperature value, the first target power value, the first voltage value, and the first current value do not meet the first correction condition, but the first temperature value, the second target power value, the second voltage value, and the second current value meet the second correction condition, the power correction value is the second target power value.
[0028] In some embodiments, determining the power correction value based on the first correction condition and the second correction condition includes:
[0029] If the first temperature value, the first target power value, the first voltage value, and the first current value satisfy the first correction condition, and the first temperature value, the second target power value, the second voltage value, and the second current value satisfy the second correction condition, the power correction value is determined based on the first target power value and the second target power value.
[0030] In some embodiments, determining the power correction value based on the first target power value and the second target power value includes:
[0031] The power correction value is the minimum value between the first target power value and the second target power value.
[0032] In some embodiments, correcting the remaining battery capacity based on the power correction value includes:
[0033] If the power correction value is less than the remaining power value, the remaining power value of the battery is set to the power correction value; if the power correction value is greater than or equal to the remaining power value, the remaining power value of the battery is not modified.
[0034] In some embodiments, before determining the battery charge correction value based on the first voltage value, the first current value, the second voltage value, and the second current value, the method includes:
[0035] The constant current discharge curve is generated based on the temperature change, instantaneous voltage, and instantaneous remaining charge.
[0036] In a second aspect, a controller is proposed, including a memory and a processor; the memory stores a computer program, and the processor is used to run the computer program in the memory to execute the battery power correction method described in the first aspect of this application.
[0037] A third aspect of this application provides a battery management system, including the controller described in the second aspect of this application.
[0038] A fourth aspect of this application provides a battery including the battery management system described in the third aspect of this application.
[0039] A fifth aspect of this application provides a vehicle comprising the battery described in the fourth aspect of this application.
[0040] This application obtains a first voltage value and a first current value at the current moment when the battery is in a discharging state, and calculates a second voltage value and a second current value from the first voltage value and the first current value. A battery capacity correction value is determined using the first voltage value, the first current value, the second voltage value, and the second current value. The remaining battery capacity is then corrected based on this correction value. Compared with existing technologies, this method improves the accuracy of calculating the remaining battery capacity by using the first voltage value and the first current value at the current moment when the battery is in a discharging state, combining these values with corrections to generate a second voltage value and a second current value with a smooth curve during the battery's discharge process, generating a battery capacity correction value, and then correcting the remaining battery capacity based on this correction value.
[0041] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description
[0042] 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 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.
[0043] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.
[0044] Figure 1 This is a schematic diagram of a battery power correction method according to an embodiment of this application;
[0045] Figure 2 This is a schematic diagram of a dynamic control curve for battery charging current according to an embodiment of this application;
[0046] Figure 3 This is a schematic diagram of temperature rise during a constant current discharge test process according to an embodiment of this application;
[0047] Figure 4 This is a lookup process for the remaining charge of a battery according to one embodiment of this application;
[0048] Figure 5 This is a schematic diagram of a controller structure according to an embodiment of this application. Detailed Implementation
[0049] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.
[0050] The theoretical basis of this application is that when a power battery is in a constant current discharge state, its voltage curve, after prolonged polarization, is theoretically lower than the dynamic discharge voltage. Therefore, the actual SOC of the battery cell will theoretically not be higher than the SOC obtained by looking up the table based on this voltage curve. The algorithm incorporates the constant current discharge curve of the power battery obtained from pre-offline cell testing. When the battery is in discharge mode, if the temperature meets the requirements, the SOC is obtained by looking up the table based on the current discharge current and voltage or smoothed current and voltage and temperature. If the current vehicle SOC is higher than the table SOC, it can be considered that the current SOC is too high, and it is adjusted down to the table SOC.
[0051] Specifically, embodiments of this application provide a method for correcting the remaining state of charge (SOC) of a battery, such as... Figure 1 As shown, the method includes:
[0052] S101: Obtain the first voltage value and the first current value of the battery at the current moment when the battery is in a discharging state;
[0053] S102: Calculate the second voltage value and the second current value of the battery based on the first voltage value and the first current value;
[0054] S103: Determine the battery charge correction value based on the first voltage value, the first current value, the second voltage value, and the second current value;
[0055] S104: Correct the remaining battery capacity value according to the power correction value.
[0056] In the Battery Management System (BMS) of a power battery, the first voltage and first current values of the battery at the current moment during discharge are typically acquired in real time. However, during battery discharge, the voltage recovery rates of the multiple cells differ, and the discharge current is also affected by temperature, resulting in deviations from the actual voltage and current values of the battery. Therefore, it is necessary to calculate the second voltage and second current values of the battery based on the first voltage and first current values. These second voltage and second current values represent the true voltage and current values of the battery under temperature influence.
[0057] Then, by combining the first voltage value, the first current value, the second voltage value, and the second current value, the battery's charge correction value is determined. The remaining charge value of the battery is then corrected based on this correction value to ensure accurate dynamic correction of the battery's State of Charge (SOC). This significantly reduces accumulated errors, especially when the battery is under high-current pulse discharge, experiencing sudden temperature changes, or after battery aging. This application significantly improves the accuracy of SOC estimation errors when the battery is in a low charge range (e.g., SOC less than 30%).
[0058] This application obtains a first voltage value and a first current value at the current moment when the battery is in a discharging state, and calculates a second voltage value and a second current value from the first voltage value and the first current value. A battery capacity correction value is determined using the first voltage value, the first current value, the second voltage value, and the second current value. The remaining battery capacity is then corrected based on this correction value. Compared with existing technologies, this method improves the accuracy of calculating the remaining battery capacity by using the first voltage value and the first current value at the current moment when the battery is in a discharging state, combining these values with corrections to generate a second voltage value and a second current value with a smooth curve during the battery's discharge process, generating a battery capacity correction value, and then correcting the remaining battery capacity based on this correction value.
[0059] In some embodiments, calculating the second voltage value and the second current value of the battery based on the first voltage value and the first current value of the battery includes:
[0060] The forgetting factor is determined based on the first temperature value of the battery;
[0061] The second voltage value is calculated based on the first voltage value and the forgetting factor;
[0062] The second current value is calculated based on the first current value and the forgetting factor.
[0063] Optionally, calculating the second voltage and second current values of the battery based on the first voltage and first current values includes: determining a forgetting factor based on the first temperature value of the battery; calculating the second voltage value based on the first voltage value and the forgetting factor; and calculating the second current value based on the first current value and the forgetting factor. The forgetting factor λ is calculated by associating the battery surface temperature T collected by the temperature sensor with a preset temperature-aging model, and its expression is:
[0064] λ = exp(-k·(T - T_ref));
[0065] Where λ is the forgetting factor, k is the temperature sensitivity coefficient, and T_ref is the reference temperature.
[0066] The forgetting factor ranges from 0 to 1. It is used to weight historical data, making the filter more dependent on the current measured value at low temperatures (λ approaches 1) and more dependent on historical trends at high temperatures (λ approaches 0), thereby suppressing polarization drift at high temperatures and voltage hysteresis at low temperatures.
[0067] Therefore, the expression for calculating the second voltage value using the forgetting factor and the first voltage value is:
[0068] V2 = λ·V2+ (1-λ)·V1;
[0069] Where V2 is the second voltage value, λ is the forgetting factor, and V1 is the first voltage value.
[0070] The expression for calculating the second current value using the forgetting factor and the first current value is:
[0071] I2 = λ·I2 + (1-λ)·I1;
[0072] Where I2 is the second current value, λ is the forgetting factor, and I1 is the first current value.
[0073] Dynamic smoothing of the first voltage and first current values is achieved by using a first-order low-pass filter to generate the second voltage and second current values, which can effectively eliminate transient noise interference.
[0074] In some embodiments, determining the battery charge correction value based on the first voltage value, the first current value, the second voltage value, and the second current value includes:
[0075] When the first temperature value is greater than or equal to the first temperature threshold
[0076] The first target charge value is obtained by querying the constant current discharge curve based on the first voltage value, the first current value, the first temperature value, and the health status of the battery.
[0077] The second target charge value is obtained by querying the constant current discharge curve based on the second voltage value, the second current value, the first temperature value, and the health status of the battery.
[0078] The first correction condition is determined based on the first temperature value, the first target charge value, the first voltage value, and the first current value;
[0079] The second correction condition is determined based on the first temperature value, the second target charge value, the second voltage value, and the second current value;
[0080] The power correction value is determined based on the first correction condition and the second correction condition.
[0081] Optionally, the battery capacity correction value is determined based on a first voltage value, a first current value, a second voltage value, and a second current value. This includes: when the first temperature value is greater than or equal to a first temperature threshold, obtaining a first target capacity value by querying a constant current discharge curve based on the first voltage value, the first current value, the first temperature value, and the battery's State of Health (SOH); obtaining a second target capacity value by querying a constant current discharge curve based on the second voltage value, the second current value, the first temperature value, and the battery's State of Health (SOH); determining a first correction condition based on the first temperature value, the first target capacity value, the first voltage value, and the first current value; determining a second correction condition based on the first temperature value, the second target capacity value, the second voltage value, and the second current value; and determining the capacity correction value based on the first and second correction conditions. The first temperature threshold is typically set to 15°C, but can be adjusted based on the battery's usage scenario and discharge performance, and is not limited here.
[0082] The constant current discharge curves are constructed by the battery manufacturer through standard constant current discharge experiments at different State of Health (SOH) levels (e.g., from 100% to 70%) and temperature ranges (e.g., -20℃ to 45℃), and stored in the controller's memory. Each curve corresponds to a two-dimensional SOH-temperature index. This mechanism is the first to achieve adaptive updates of the discharge curves as the battery ages, overcoming the defect of traditional fixed curves that misjudge the State of Charge (SOC) after aging.
[0083] In some embodiments, the first correction condition includes:
[0084] The first target power value is less than the first remaining power threshold, and the first current value is the maximum discharge pulse current value of the battery within the first time interval, and the first voltage value is greater than the difference between the voltage value and the average voltage value but less than a preset voltage difference.
[0085] The average voltage value is the average of the voltages of all cells in the battery.
[0086] Optionally, based on battery polarization characteristics, for example, during battery discharge, a process of first discharging with a small current and then discharging with a large current results in a higher voltage than continuous high current discharge. Therefore, the SOC obtained from the current high-rate current curve is higher than the theoretical value. Thus, it is safer to take the maximum of the battery's maximum discharge pulse current value within the first time interval as the first current value. The first current value and the first time interval can be adjusted according to actual test conditions. Simultaneously, since the battery contains multiple cells, the average voltage value is the average voltage of all cells in the battery. It is necessary to ensure that the first voltage value is close to the average voltage value. Therefore, the first correction condition needs to meet the following conditions: the first target charge value is less than the first remaining charge threshold, the first current value is the maximum discharge pulse current value of the battery within the first time interval, and the first voltage value is greater than the difference between the first and average voltage values but less than a preset voltage difference; where the average voltage value is the average voltage of all cells in the battery. The values of the first remaining charge threshold, the first time interval, and the preset voltage difference can be set according to the battery's application scenario, battery performance, and vehicle performance.
[0087] For example, the first remaining battery capacity threshold is typically set to 30%, the first time interval is 300 seconds, the maximum discharge pulse current is 5C, and the preset voltage difference is 0.05V. The first correction condition must meet the following conditions: the first target battery capacity is less than 30%, the first current value is the maximum discharge pulse current value of the battery within 300 seconds (i.e., 5C), and the first voltage value is greater than the average voltage of all cells in the battery, with the difference being less than 0.05V. Otherwise, the first correction condition is not met.
[0088] In some embodiments, the second correction condition includes:
[0089] When the second target power value is less than the second remaining power threshold and the first temperature value is less than the second temperature threshold, the difference between the first current value and the second current value is greater than the first preset current value.
[0090] Optionally, because the battery voltage recovers slowly after a voltage drop caused by a large current pulse when the battery is at low temperatures, the SOC obtained from the table based on the current low rate and low voltage is too low and should not be used. Therefore, the second correction condition needs to meet the following conditions: the first temperature value is less than the second temperature threshold, the difference between the first current value and the second current value is greater than the first preset current value, and the second target charge value is less than the second remaining charge threshold. The values of the second temperature threshold, the first preset current value, and the second remaining charge threshold can be set according to the battery's application scenario, battery performance, and vehicle performance.
[0091] For example, if the second temperature threshold is set to 15℃, the first preset current value is 0.3A, and the second remaining power threshold is 8%, then the second correction condition must meet the following conditions: the first temperature value is less than 15℃, the difference between the first current value and the second current value is greater than 0.3A, and the second target power value is less than 8%; otherwise, the second correction condition is not met.
[0092] In some embodiments, determining the power correction value based on the first correction condition and the second correction condition includes:
[0093] If the first temperature value, the first target power value, the first voltage value, and the first current value satisfy the first correction condition, and the first temperature value, the second target power value, the second voltage value, and the second current value do not satisfy the second correction condition, the power correction value is the first target power value.
[0094] Optionally, the power correction value is determined according to the first correction condition and the second correction condition, including: when the first temperature value, the first target power value, the first voltage value, and the first current value satisfy the first correction condition, and the first temperature value, the second target power value, the second voltage value, and the second current value do not satisfy the second correction condition, the power correction value is the first target power value.
[0095] The first correction condition is used to identify the voltage drop caused by the internal resistance voltage drop of the battery under high-rate discharge. If the first voltage value of the battery deviates little from the average voltage value of all telecommunications batteries, it indicates good battery consistency, and the voltage drop truly reflects the power consumption. Therefore, the first target capacity value under the first correction condition should be used to correct the SOC. This strategy prioritizes the use of measured data under high-temperature, high-rate discharge conditions to avoid overestimation of SOC due to filtering delay.
[0096] In some embodiments, determining the power correction value based on the first correction condition and the second correction condition includes:
[0097] If the first temperature value, the first target power value, the first voltage value, and the first current value do not meet the first correction condition, but the first temperature value, the second target power value, the second voltage value, and the second current value meet the second correction condition, the power correction value is the second target power value.
[0098] Optionally, the power correction value is determined according to the first correction condition and the second correction condition, including: if the first temperature value, the first target power value, the first voltage value, and the first current value do not meet the first correction condition, and the first temperature value, the second target power value, the second voltage value, and the second current value meet the second correction condition, the power correction value is the second target power value.
[0099] Because the second correction condition is used to identify the current response lag caused by the decrease in lithium-ion diffusion rate under low-temperature conditions, the measured first current value may be too high due to sensor delay. The filtered current value (second current value) is closer to the true electrochemical response, and the filtered value should be used to correct the SOC. This strategy prioritizes the use of the filtered predicted value under low-temperature and low-current conditions to avoid underestimating the SOC due to current sampling delay.
[0100] In some embodiments, determining the power correction value based on the first correction condition and the second correction condition includes:
[0101] If the first temperature value, the first target charge value, the first voltage value, and the first current value satisfy the first correction condition, and the first temperature value, the second target charge value, the second voltage value, and the second current value satisfy the second correction condition, then...
[0102] The power correction value is determined based on the first target power value and the second target power value.
[0103] Optionally, the power correction value is determined based on the first correction condition and the second correction condition, including: when the first temperature value, the first target power value, the first voltage value, and the first current value satisfy the first correction condition, and the first temperature value, the second target power value, the second voltage value, and the second current value satisfy the second correction condition, the power correction value is determined based on the first target power value and the second target power value. This situation occurs at the intersection of extreme operating conditions, such as low-temperature high-rate discharge, where the system enters a dual-condition triggering mode and initiates a decision fusion mechanism; therefore, the power correction value is determined using the first target power value and the second target power value.
[0104] In some embodiments, determining the power correction value based on the first target power value and the second target power value includes:
[0105] The power correction value is the minimum of the first target power value and the second target power value.
[0106] Optionally, a power correction value can be determined based on a first target power value and a second target power value, including: the power correction value being the minimum of the first target power value and the second target power value. In this case, by taking the minimum of the first target power value and the second target power value as the power correction value, a conservative correction can be made to the remaining SOC, ensuring that the safety of the range prediction is prioritized when uncertainty is highest, and avoiding the risk of over-discharge.
[0107] In some embodiments, correcting the remaining battery capacity based on the power correction value includes:
[0108] If the power correction value is less than the remaining power value, the remaining power value of the battery is set as the power correction value.
[0109] If the power correction value is greater than or equal to the remaining power value, the remaining power value of the battery will not be modified.
[0110] Optionally, the remaining battery capacity can be corrected based on a power correction value. This includes: setting the remaining battery capacity to the correction value if the correction value is less than the remaining capacity; and not modifying the remaining battery capacity if the correction value is greater than or equal to the remaining capacity. Generally, if the correction value is greater than or equal to the remaining capacity, it indicates a problem with the correction data or that the battery's State of Charge (SOC) does not need correction. If the correction value is less than the remaining capacity, the SOC needs to be corrected, and the remaining capacity is set to the correction value. This method prevents the SOC from being erroneously inflated, ensures one-way correction, avoids "battery jumps" caused by noise-induced false triggering, and increases user confidence in the battery life prediction.
[0111] In some embodiments, before determining the battery charge correction value based on the first voltage value, the first current value, the second voltage value, and the second current value, the method includes:
[0112] The constant current discharge curve is generated based on temperature, instantaneous voltage, and instantaneous remaining charge.
[0113] Optionally, since this application obtains the first target charge value and the second target charge value by querying the pre-built constant current discharge curve using the first voltage value, the first current value, the second voltage value, and the second current value, before determining the battery charge correction value based on the first voltage value, the first current value, the second voltage value, and the second current value, it is necessary to generate a constant current discharge curve based on experimental data, the battery temperature change, instantaneous voltage, and instantaneous remaining charge.
[0114] Because the instantaneous voltage of a battery's constant current discharge is significantly affected by the battery's temperature and instantaneous discharge current rate, and this effect is monotonic—the higher the instantaneous discharge current rate and the lower the temperature, the lower the instantaneous voltage under the same SOC conditions—the built-in curves need to take these parameters into account. Testing battery cells requires testing discharge curves at different discharge current rates and temperatures, and needs to cover different vehicle usage scenarios. Therefore, the discharge current rate and temperature range should be as wide as possible. For cells in different aging states, constant current discharge curves under different SOH conditions can be tested in advance and incorporated into the controller. Alternatively, the relationship between SOC-voltage curves and SOH formulas can be obtained based on the relationship between curves at the same rate and temperature under different SOH conditions. After obtaining the SOC lookup table value of the cell curve at the initial stage of the battery's life cycle, this formula can be used for mapping to obtain the corrected SOC value for the entire life cycle.
[0115] The generation process is performed by the controller in real time during vehicle operation, or by generating constant current discharge curves in real time under simulated vehicle operation conditions in the laboratory. After each complete discharge cycle (SOC from 90% to 10%), the system collects temperature change curves, instantaneous discharge current ratio, instantaneous voltage and corresponding SOC data, and generates new constant current discharge curve segments by fitting the data using the least squares method, updating the curve library in the controller's memory, thus realizing the self-learning and self-adaptation of the discharge model.
[0116] For example, such as Figure 2 As shown, the instantaneous discharge current of the battery is set to 0.1C, 0.3C, ..., 1C, 2C, with corresponding temperatures of -25℃, -20℃, ..., 40℃, 45℃, for a total of 12 test groups (parameter curves can be added or removed according to actual test conditions). By combining the instantaneous voltage and the corresponding SOC, 12 voltage-SOC curves at different rates and temperatures can be obtained. The voltage-charge data points collected within each interval are clustered, and a weighted fitting is performed using the SOH value to generate a dynamic discharge curve matrix with temperature and SOH dimensions. The dynamic discharge curve matrix can also be updated periodically to ensure that the constant current discharge curve model always reflects the battery's true aging and thermal response characteristics.
[0117] At the same time, such as Figure 3 As shown, when obtaining the target SOC value from the constant current discharge curve, the impact of temperature T changes during the constant current discharge test on the battery SOC must be considered. Because the constant current discharge process is continuous, even with controlled initial temperature, a temperature rise will occur during discharge, and the temperature rise trend is as follows... Figure 3 Curve 2 in the middle, therefore according to Figure 3Treating the discharge curve of line 2 in the figure as an isothermal curve will cause a large deviation. To solve the SOC error caused by this phenomenon, the temperature during the constant current discharge process needs to be imported into the model as a variable with the same change as the voltage, so as to obtain a three-dimensional curve of SOC-voltage-temperature at a certain discharge rate. Then, the dimensions are reduced step by step to finally obtain the target SOC.
[0118] The specific query process is as follows: Each discharge curve with the same rate corresponds to n three-dimensional voltage-temperature-SOC curves. Based on the voltage-temperature-SOC table, the corresponding SOC array [SOC0, SOC1, ... SOCn] and temperature array [T0, T1, ... Tn] are obtained. Based on the current temperature Tmin, the [T0, T1, ... Tn]-[SOC0, SOC1, ... SOCn] table obtained in the above operation is looked up. Linear interpolation is performed based on Tmin to obtain SOCTarget. The same operation is performed on the two rate curves adjacent to the current current rate, and finally the SOC lookup results [SOCTarget1, SOCTarget2] under different discharge rates are obtained. Linear interpolation is performed on the [SOCTarget1, SOCTarget2] table according to the current rate I to obtain SOCTarget.
[0119] Taking an instantaneous voltage of 2700mV, a temperature of 25℃, and an instantaneous discharge current ratio of 1.3C as an example, the query process is as follows: Figure 4 As shown: First, based on the instantaneous voltage of 2700mV, temperature of 25℃, and instantaneous discharge current ratio of 1.3C, look up the voltage-temperature-SOC table to obtain the corresponding first SOC array [SOC0, SOC1, SOC2, SOC3] and the first temperature T array [T0, T1, T2, T3]; take the SOC2 corresponding to temperature 25℃ (T2), and denot it as SOC_1c. Then, look up the voltage-temperature-SOC table on the two adjacent current ratio curves to obtain the corresponding second SOC array [SOC0, SOC1, SOC2, SOC3] and the first temperature T array [T0, T1, T2, T3]; take the SOC2 corresponding to temperature 25℃ (T2), and denot it as SOC_2c. Linear interpolation was performed between the instantaneous discharge current multiplier of 1.3C and the [SOC_1c, SOC_2c] table corresponding to the temperature of 25℃T2 obtained from the two queries to obtain the final result SOC@[2700mV, 25℃, 1.3C].
[0120] This application embodiment also provides a controller, the controller comprising:
[0121] Memory and processor;
[0122] The memory stores a computer program, and the processor is used to run the computer program in the memory to execute the battery power correction method of the present application embodiment.
[0123] Figure 5 This is a structural block diagram of the controller according to an embodiment of the present invention.
[0124] like Figure 5 As shown, the controller 500 includes a processor 501 and a memory 503. The processor 501 and the memory 503 are connected, for example, via a bus 502. Optionally, the controller 500 may also include a transceiver 504. It should be noted that in practical applications, the transceiver 504 is not limited to one, and the structure of the controller 500 does not constitute a limitation on the embodiments of the present invention.
[0125] The controller in this application is connected to the BMS system and the power battery system, and acquires the temperature of the temperature monitoring device in the BMS system in real time at a preset acquisition cycle, and then sends it to the memory 503 for storage. The battery power correction method of this application is then processed by the processor 501.
[0126] The processor 501 may be a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this invention. The processor 501 may also be a combination that implements computational functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.
[0127] Bus 502 may include a path for transmitting information between the aforementioned components. Bus 502 may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. Bus 502 can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 5 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.
[0128] The memory 503 is used to store a computer program corresponding to the data processing method of the above embodiments of the present invention, and the computer program is controlled and executed by the processor 501. The processor 501 is used to execute the computer program stored in the memory 503 to implement the content shown in the foregoing method embodiments.
[0129] The controller 500 includes, but is not limited to, mobile terminals such as mobile phones, laptops, digital radio receivers, personal digital assistants (PDAs), tablet computers (PADs), portable multimedia players (PMPs), and in-vehicle terminals (such as in-vehicle navigation terminals), as well as fixed terminals such as digital TVs and desktop computers. Figure 5 The controller 500 shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments of the present invention.
[0130] This application also provides a battery management system, including the controller described above.
[0131] The battery management system of this application includes the controller described above, and can execute the battery power correction method described above.
[0132] The battery management system of this application obtains a first voltage value and a first current value at the current moment when the battery is in a discharging state, and calculates a second voltage value and a second current value from the first voltage value and the first current value. A battery charge correction value is determined using the first voltage value, the first current value, the second voltage value, and the second current value, and then the remaining battery charge value is corrected based on the charge correction value. Compared with the prior art, by using the first voltage value and the first current value at the current moment when the battery is in a discharging state, and combining the correction of the first voltage value and the first current value to generate a second voltage value and a second current value with a smooth curve during the battery's discharge process, the battery charge correction value is generated, and the remaining battery charge value is corrected based on the charge correction value, which improves the accuracy of calculating the remaining battery charge.
[0133] This application also provides a battery, including the battery management system described above.
[0134] The battery in this application embodiment includes the battery management system described above, and the battery includes a lithium-ion battery or a battery with other structures.
[0135] This application's battery can obtain a first voltage value and a first current value at the current moment when the battery is in a discharging state, and calculate a second voltage value and a second current value from the first voltage value and the first current value. A battery capacity correction value is determined using the first voltage value, the first current value, the second voltage value, and the second current value, and then the remaining battery capacity value is corrected based on the capacity correction value. Compared with existing technologies, this method, by using the first voltage value and the first current value at the current moment when the battery is in a discharging state, and combining this with the correction of the first voltage value and the first current value to generate a second voltage value and a second current value with a smooth curve during the battery's discharge process, generates a battery capacity correction value, and then corrects the remaining battery capacity value based on the capacity correction value, thus improving the accuracy of the remaining battery capacity calculation.
[0136] This application also provides a vehicle including the aforementioned battery.
[0137] The vehicle in this application embodiment includes the battery described above. The vehicle is a new energy vehicle. The battery management system is integrated into the vehicle domain controller and is connected to the vehicle controller, thermal management system, etc. via CAN bus. This enables closed-loop control of battery charging current and coordinated optimization of power correction.
[0138] This application describes a method for determining the battery's remaining charge level by acquiring the first voltage and first current values at the current moment when the battery is discharging. The method calculates a second voltage and a second current value based on these values, determines a charge correction value, and then adjusts the remaining charge level accordingly. Compared to existing technologies, this method uses the first voltage and first current values at the current moment when the battery is discharging. It combines these values with adjustments to generate a second voltage and a second current value with a smooth discharge curve, generates a charge correction value, and then adjusts the remaining charge level based on this value. This improves the accuracy of remaining charge level calculation, preventing errors in mileage calculation due to abnormal battery charge level display, which could lead to breakdowns or other safety incidents.
[0139] This application also provides a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. The vehicle's processor reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the vehicle to perform the battery power correction method provided in the various optional implementations of the above embodiments.
[0140] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be performed by a computer program, or by a computer program controlling related hardware. The computer program can be stored in a computer-readable storage medium and loaded and executed by a processor.
[0141] According to one aspect of this application, a computer-readable storage medium is provided that stores instructions that, when executed by a processor, configure the processor to perform the aforementioned battery power correction method.
[0142] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, compact disc read-only memory (CD-ROM), optical storage, etc.) containing computer-usable program code.
[0143] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0144] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0145] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0146] In a typical configuration, a computing device includes one or more processors (Central Processing Unit, CPU), input / output interfaces, network interfaces, and memory.
[0147] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash memory (flash RAM). Memory is an example of computer-readable media.
[0148] Computer-readable media include both permanent and non-permanent, removable and non-removable media, which can store information using any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random-access memory (SRAM), dynamic random-access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device. As defined in this article, computer-readable media do not include transient media, such as modulated communication signals and carrier waves.
[0149] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0150] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.
[0151] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.
[0152] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.
Claims
1. A battery charge correction method, characterized in that, include: Obtain the first voltage value and the first current value of the battery at the current moment when the battery is in a discharging state; Calculate the second voltage value and the second current value of the battery based on the first voltage value and the first current value; The battery charge correction value is determined based on the first voltage value, the first current value, the second voltage value, and the second current value; The remaining battery capacity is corrected based on the stated capacity correction value.
2. The method according to claim 1, characterized in that, The step of calculating the second voltage value and the second current value of the battery based on the first voltage value and the first current value of the battery includes: The forgetting factor is determined based on the first temperature value of the battery; The second voltage value is calculated based on the first voltage value and the forgetting factor; The second current value is calculated based on the first current value and the forgetting factor.
3. The method according to claim 1, characterized in that, Determining the battery charge correction value based on the first voltage value, the first current value, the second voltage value, and the second current value includes: When the first temperature value is greater than or equal to the first temperature threshold The first target charge value is obtained by querying the constant current discharge curve based on the first voltage value, the first current value, the first temperature value, and the health status of the battery. The second target charge value is obtained by querying the constant current discharge curve based on the second voltage value, the second current value, the first temperature value, and the health status of the battery. The first correction condition is determined based on the first temperature value, the first target charge value, the first voltage value, and the first current value; The second correction condition is determined based on the first temperature value, the second target charge value, the second voltage value, and the second current value; The power correction value is determined based on the first correction condition and the second correction condition.
4. The method according to claim 3, characterized in that, The first correction condition includes: The first target power value is less than the first remaining power threshold, and the first current value is the maximum discharge pulse current value of the battery within the first time interval, and the first voltage value is greater than the difference between the voltage value and the average voltage value but less than a preset voltage difference. The average voltage value is the average of the voltages of all cells in the battery.
5. The method according to claim 3, characterized in that, The second modification condition includes: When the second target power value is less than the second remaining power threshold and the first temperature value is less than the second temperature threshold, the difference between the first current value and the second current value is greater than the first preset current value.
6. The method according to claim 3, characterized in that, Determining the power correction value based on the first correction condition and the second correction condition includes: If the first temperature value, the first target power value, the first voltage value, and the first current value satisfy the first correction condition, and the first temperature value, the second target power value, the second voltage value, and the second current value do not satisfy the second correction condition, the power correction value is the first target power value.
7. The method according to claim 3, characterized in that, Determining the power correction value based on the first correction condition and the second correction condition includes: If the first temperature value, the first target power value, the first voltage value, and the first current value do not meet the first correction condition, but the first temperature value, the second target power value, the second voltage value, and the second current value meet the second correction condition, the power correction value is the second target power value.
8. The method according to claim 3, characterized in that, Determining the power correction value based on the first correction condition and the second correction condition includes: If the first temperature value, the first target charge value, the first voltage value, and the first current value satisfy the first correction condition, and the first temperature value, the second target charge value, the second voltage value, and the second current value satisfy the second correction condition, then... The power correction value is determined based on the first target power value and the second target power value.
9. The method according to claim 8, characterized in that, Determining the power correction value based on the first target power value and the second target power value includes: The power correction value is the minimum of the first target power value and the second target power value.
10. The method according to claim 1, characterized in that, The step of correcting the remaining battery capacity based on the power correction value includes: If the power correction value is less than the remaining power value, the remaining power value of the battery is set as the power correction value. If the power correction value is greater than or equal to the remaining power value, the remaining power value of the battery will not be modified.
11. The method according to claim 3, characterized in that, Before determining the battery charge correction value based on the first voltage value, the first current value, the second voltage value, and the second current value, the process includes: The constant current discharge curve is generated based on the temperature change, instantaneous voltage, and instantaneous remaining charge.
12. A controller, characterized in that, include: Memory and processor; The memory stores a computer program, and the processor is configured to run the computer program in the memory to perform the battery power correction method according to any one of claims 1 to 11.
13. A battery management system, characterized in that, Includes the controller as described in claim 12.
14. A battery, characterized in that, Includes the battery management system described in claim 13.
15. A vehicle, characterized in that, Includes the battery described in claim 14.