Battery power extraction method, battery power extraction apparatus, device, and medium

Abstract

The embodiment of the application provides a battery power extraction method, a battery power extraction device, equipment and a medium, and belongs to the technical field of batteries. The method comprises the following steps: performing constant-voltage pulse testing on a target battery under a first parameter group to obtain first limit power values at multiple time points; performing time extrapolation fitting according to the multiple first limit power values to obtain a first power-time relationship equation; determining second limit power values of the target battery at multiple test temperatures under a second parameter group; performing temperature extrapolation fitting according to the multiple second limit power values to obtain a power-temperature relationship equation; and performing power extraction according to the first power-time relationship equation and the power-temperature relationship equation to obtain a permissible limit power value. According to the embodiment of the application, only a small amount of test data is needed to extrapolate the limit power values covering the full time, full temperature and full state of charge, so that the battery power extraction efficiency and accuracy are improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery power extraction method, battery power extraction device, equipment and medium. Background Technology

[0002] In related technologies, the hybrid pulse power characteristic (HPPC) standard test method is typically used for battery charge / discharge limit power testing. HPPC testing is based on constant current pulses. To obtain the limit power at different time scales (e.g., 5s, 10s, 30s, 60s), it is often necessary to perform long-duration discrete pulse tests for each time point, or to conduct multiple rounds of testing. This traditional constant current testing method presents a trade-off between workload and data accuracy: to cover different states of charge, different temperatures, and different pulse durations, each pulse needs to be left to stand still for a long time to ensure a stable initial state. If the test matrix is ​​extremely large, the test cycle can last for weeks or even months, consuming a significant amount of manpower and resources. Reducing the test data and supplementing the remaining data through fitting, on the other hand, leads to a decrease in data accuracy. Summary of the Invention

[0003] The main objective of this application is to propose a battery power extraction method, a battery power extraction device, an equipment, and a medium that can extrapolate the ultimate power value covering the entire time, temperature, and state of charge with only a small amount of test data, thereby improving the efficiency and accuracy of battery power extraction.

[0004] To achieve the above objectives, a first aspect of this application proposes a battery power extraction method, the method comprising: A constant voltage pulse test is performed on the target battery under a first set of parameters to obtain a first limit power value at multiple moments within the pulse duration; wherein, the first set of parameters includes a test temperature and a state of charge, and the first limit power value is obtained under the extreme condition of maintaining the potential of the target battery at a safe threshold boundary; The first power-time relationship equation is obtained by extrapolating and fitting multiple first limit power values ​​over time. Based on the power value obtained from the constant voltage pulse test and / or the power value calculated using the first power-time relationship equation, a second limit power value for the target battery at multiple test temperatures under the second parameter set is determined; wherein, the second parameter set includes a state of charge and a time. By performing temperature extrapolation fitting based on multiple second limit power values, a power-temperature relationship equation is obtained. Power is extracted based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value.

[0005] Optionally, the step of extracting power based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value includes: By using the first power-time relationship equation, power values ​​are extrapolated to obtain time-extrapolated power values ​​for multiple unmeasured time points; By using the power-temperature relationship equation, power values ​​are extrapolated to obtain power values ​​for multiple unmeasured temperatures. Based on all the time extrapolated power values ​​and all the temperature extrapolated power values, a power mapping table corresponding to temperature and state of charge at multiple time points is constructed. The allowable power limit value is obtained by querying the power mapping table corresponding to the current operating time of the target battery based on the current operating temperature and current state of charge of the target battery.

[0006] Optionally, the step of extracting power based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value includes: The power-temperature relationship equation is used to extrapolate the power value, and the extrapolated power value of the third parameter set at multiple times is obtained; wherein, the third parameter set includes an unmeasured temperature and a state of charge; A second power-time relationship equation is obtained by performing time extrapolation fitting based on multiple temperature extrapolation power values; Each of the first power time relationship equations and each of the second power time relationship equations are taken as the target power time relationship equations; Based on the slope in the target power time relationship equation, a slope mapping table corresponding to temperature and state of charge is constructed; based on the intercept in the target power time relationship equation, an intercept mapping table corresponding to temperature and state of charge is constructed. The allowable power slope is obtained by querying the slope mapping table based on the current operating temperature and current state of charge of the target battery, and the allowable power intercept is obtained by querying the intercept mapping table. The allowable power limit value is calculated based on the allowable power slope, the allowable power intercept, and the current operating time of the target battery.

[0007] Optionally, the step of extracting power based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value further includes: Temperature extrapolation fitting is performed based on the slopes in multiple target power time relationship equations to obtain slope temperature relationship equations; Temperature extrapolation fitting is performed based on the intercepts in multiple target power time relationship equations to obtain intercept temperature relationship equations; Power state parameters are extracted from the slope temperature relation equation and the intercept temperature relation equation, and a power state parameter mapping table corresponding to the state of charge is constructed based on the power state parameters. The allowable power state parameters are obtained by querying the power state parameter mapping table based on the current operating state of charge of the target battery. The allowable power slope and allowable power intercept are calculated based on the allowable power state parameters and the current operating temperature of the target battery. The allowable limit power value is calculated based on the allowable power slope, the allowable power intercept, and the current operating time of the target battery.

[0008] Optionally, the step of performing time extrapolation fitting based on multiple first limiting power values ​​to obtain a first power-time relationship equation includes: The power-time coordinate is obtained by taking the reciprocal of the first limiting power value as the vertical axis and the square root of the time corresponding to the first limiting power value as the horizontal axis. The first power-time relationship equation is obtained by linear fitting based on multiple power-time coordinates.

[0009] Optionally, the step of performing temperature extrapolation fitting based on multiple second limiting power values ​​to obtain a power-temperature relationship equation for power changing with temperature includes: The power-temperature coordinate is obtained by taking the logarithm of the second limiting power value as the vertical axis and the reciprocal of the test temperature corresponding to the second limiting power value as the horizontal axis. The power-temperature relationship equation is obtained by linear fitting of multiple power-temperature coordinates.

[0010] Optionally, the step of performing a constant voltage pulse test on the target battery under the first parameter set to obtain a first limit power value at multiple moments within the pulse duration includes: Under the first parameter set, a constant voltage pulse test is performed on the target battery according to the constant voltage potential to obtain the measured current decay curve within the pulse duration. The current at multiple moments in the measured current decay curve is multiplied by the constant voltage potential to obtain the first limit power value at multiple moments.

[0011] To achieve the above objectives, a second aspect of this application provides a battery power extraction device, the device comprising: The first power acquisition module is used to perform a constant voltage pulse test on the target battery under a first parameter set to obtain a first limit power value at multiple moments within the pulse duration; wherein, the first parameter set includes a test temperature and a state of charge, and the first limit power value is obtained under the extreme condition of maintaining the potential of the target battery at a safe threshold boundary; The time extrapolation fitting module is used to perform time extrapolation fitting based on multiple first limit power values ​​to obtain a first power-time relationship equation. The second power acquisition module is used to determine the second limit power value of the target battery at multiple test temperatures under the second parameter set based on the power value obtained from the constant voltage pulse test and / or the power value calculated using the first power-time relationship equation; wherein the second parameter set includes a state of charge and a time. The temperature extrapolation and fitting module is used to perform temperature extrapolation and fitting based on multiple second limit power values ​​to obtain a power-temperature relationship equation. The power extraction module is used to extract power based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value.

[0012] To achieve the above objectives, a third aspect of this application provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the method described in the first aspect.

[0013] To achieve the above objectives, a fourth aspect of the present application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the method described in the first aspect.

[0014] The battery power extraction method, battery power extraction device, electronic device, and computer-readable storage medium proposed in this application first perform a constant voltage pulse test on the target battery under a first parameter set (the first parameter set includes a test temperature and a state of charge), obtaining first limit power values ​​at multiple moments, and then obtaining a first power-time relationship equation corresponding to the test temperature and state of charge. In this way, by modifying the test temperature and / or state of charge, first power-time relationship equations under different first parameter sets can be obtained. Next, based on the power values ​​obtained from the constant voltage pulse test and / or the power values ​​calculated using the first power-time relationship equation, second limit power values ​​for the target battery at multiple test temperatures under a second parameter set (the second parameter set includes a state of charge and a moment), such that these second limit power values ​​are directly or indirectly related to the power values ​​obtained from the constant voltage pulse test. Then, based on the multiple second limit power values, a power-temperature relationship equation is obtained. In this way, by modifying the state of charge and / or moment, power-temperature relationship equations under different second parameter sets can be obtained. Finally, power is extracted based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value of the target battery at any temperature, any state of charge, and any time. It is evident that this application utilizes the characteristic of natural current decay under constant voltage pulse testing, requiring only a small amount of test data to extrapolate the limit power value covering all time, all temperature, and all states of charge, thus improving the efficiency and accuracy of battery power extraction. Attached Figure Description

[0015] Figure 1 This is a flowchart of the battery power extraction method provided in the embodiments of this application; Figure 2 yes Figure 1 The first flowchart of step 150; Figure 3 yes Figure 1 The second flowchart of step 150; Figure 4 yes Figure 1 The third flowchart for step 150; Figure 5 This is a schematic diagram of the hardware structure of the battery power extraction device provided in the embodiments of this application; Figure 6 This is a schematic diagram of the hardware structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0017] It should be noted that although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the device or the order in the flowchart. The terms "first," "second," etc., in the specification, claims, and the aforementioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0019] This application relates to the field of battery technology, and more specifically, to the field of battery management and state estimation technology. Specifically, it relates to a battery power extraction method based on constant voltage pulse testing across the entire time scale, temperature range, and state of charge. This battery power extraction method can be applied to battery power system control strategies.

[0020] Traditional battery charge / discharge power limit testing typically employs the Hybrid Pulse Power Characteristic (HPPC) standard test method. HPPC testing is based on constant current pulses. To obtain the power limit at different time scales (e.g., 5s, 10s, 30s, 60s), it is often necessary to perform long-duration discrete pulse tests at each time point, or to conduct multiple rounds of testing. This traditional constant current testing method has the following serious drawbacks: 1. The conflict between workload and data accuracy: To cover different states of charge (SOC), temperatures, and pulse durations, each pulse requires a long resting period to ensure a stable initial state. If the test matrix is ​​extremely large, the test cycle can last for weeks or even months, consuming a significant amount of manpower and resources. If only a small number of points are measured and the remaining data is supplemented by fitting, the data accuracy will decrease.

[0021] 2. Inability to achieve continuous coverage across the entire time scale: Traditional methods can only obtain power at specific discrete time points (such as a fixed 10s or 30s), and cannot continuously and dynamically evaluate the limiting power at any time (such as 7s, 15s or longer).

[0022] 3. Excessive memory consumption of the battery management system: To apply this data in the vehicle battery management system, traditional strategies require storing a large number of two-dimensional tables (e.g., one "temperature-SOC" two-dimensional table for each of 5s, 10s, 30s, and 60s). As the time dimension and temperature resolution increase, the non-volatile memory space of the battery management system is severely consumed, and the switching and interpolation calculations between multiple tables not only increase the algorithm complexity but also easily introduce accumulated errors.

[0023] The technical problem to be solved by this application is to overcome the shortcomings of existing HPPC constant current pulse power testing, such as long testing time, inability to cover continuous points across the entire time scale, high memory consumption due to the storage of multiple power meters in traditional battery management systems, and inability to achieve online agile calculation at arbitrary time scales.

[0024] This application aims to provide a power extraction method based on constant voltage pulse testing. By exploring the electrochemical kinetics of current decay under constant voltage pulse testing, it can extrapolate the ultimate power value covering the entire time, temperature, and SOC dimensions with only a small amount of test data. It also provides a parameterized table mapping control strategy that significantly reduces the storage space of the battery management system.

[0025] The battery power extraction method, battery power extraction device, electronic device, and computer-readable storage medium provided in this application are specifically described through the following embodiments. First, the battery power extraction method in this application is described.

[0026] Figure 1 This is an optional flowchart of the battery power extraction method provided in the embodiments of this application. Figure 1 The method may include, but is not limited to, steps 110 to 150.

[0027] Step 110: Perform a constant voltage pulse test on the target battery under the first parameter set to obtain the first limit power value at multiple moments within the pulse duration.

[0028] The first parameter set includes a test temperature and a state of charge (SOC). Multiple first parameter sets are obtained by combining multiple test temperatures and multiple SOCs in pairs. A first parameter set can be represented as (test temperature, state of charge). For example, multiple first parameter sets include (T1, SOC1), (T1, SOC2), (T1, SOC3), (T1, SOC4), (T2, SOC1), (T2, SOC2), (T2, SOC3), and (T2, SOC4).

[0029] The first limiting power value is obtained under the extreme condition of maintaining the target battery potential at the safety threshold boundary (also known as constant voltage potential).

[0030] In one embodiment, step 110 may include: Under the first parameter set, a constant voltage pulse test is performed on the target battery according to the constant voltage potential to obtain the measured current decay curve during the pulse duration. The current at multiple moments in the measured current decay curve is multiplied by the constant voltage potential to obtain the first limit power value at multiple moments.

[0031] Specifically, under the first parameter set (including set temperature and specific SOC point), a constant voltage pulse test is applied to the target battery to maintain its potential at a constant voltage level. The constant voltage potential for constant voltage pulse charging can be selected from two options: 1. Conventional test scheme: using the nominal charging cutoff voltage of the battery cell as the constant voltage clamping threshold; 2. High-precision limit test scheme (adapted to three-electrode system cells): pre-testing the three-electrode cell to calibrate the total voltage of the positive and negative electrodes corresponding to the point where the negative electrode potential exactly reaches 0V (or Li / Li+, the critical potential for lithium metal deposition), and using this voltage as the constant voltage potential for the charging constant voltage pulse. This scheme can accurately anchor the lithium deposition risk boundary of the battery cell, and the obtained charging limit power is closer to the actual safety upper limit of the battery cell, especially suitable for low-temperature charging power calibration scenarios. During the constant voltage pulse test applied to the target battery, the current decay curve I(t) is collected within the pulse duration. Finally, the product of the current value at any moment in the current decay curve and the constant voltage potential is defined as the first limit power value P at that moment. T+SOC (t) = I(t) × V.

[0032] For example, if the first parameter set is (T1, SOC1), and multiple time points include t1, t2, and t3, then the current decay curve I(t) is specifically I. T1+SOC1 (t), then the first limiting power value P of t1 can be obtained. T1+SOC1 The first limiting power values ​​P of (t1) and t2 T1+SOC1 The first limiting power values ​​P of (t2) and t3 T1+SOC1 (t3).

[0033] For example, if the first parameter set is (T2, SOC1), and multiple time points include t1, t2, and t3, then the current decay curve I(t) is specifically I. T2+SOC1 (t), then the first limiting power value P of t1 can be obtained. T2+SOC1 The first limiting power values ​​P of (t1) and t2 T2+SOC1 The first limiting power values ​​P of (t2) and t3 T2+SOC1 (t3).

[0034] Similar to the process of obtaining the first limiting power values ​​at multiple times (t1, t2, t3) when the first parameter set is (T1, SOC1) or (T2, SOC1), the first limiting power values ​​at multiple times of the first parameter set (T1, SOC2), (T1, SOC3), (T1, SOC4), (T2, SOC2), (T2, SOC3), (T2, SOC4), etc., can be obtained.

[0035] As can be seen from the example above, different sets of first parameters correspond to different current decay curves, and thus the first limit power values ​​obtained at multiple moments are also different.

[0036] It should be noted that the constant voltage pulse test should be performed at at least two test temperatures (such as T1 and T2), and at each test temperature, the constant voltage pulse test should be performed at all preset SOC points (such as SOC1, SOC2, SOC3, and SOC4) within the voltage threshold range.

[0037] In one embodiment, if the constant voltage pulse test is a constant voltage pulse discharge, the discharge test temperature is preferably in the range of -40°C to 15°C. If the constant voltage pulse test is a constant voltage pulse charge, the charging test temperature is preferably in the range of -20°C to 20°C. The constant voltage pulse duration is preferably in the range of 5s to 60s.

[0038] When performing constant voltage pulse discharge in the high SOC range, if the voltage cannot be stably clamped to the discharge cutoff voltage and an effective current decay curve cannot be obtained due to the target battery's strong discharge capacity and the initial discharge current exceeding the current output limit of the test equipment, the constant voltage pulse discharge at that SOC point at room temperature / high temperature can be omitted, and only the constant voltage pulse discharge at that SOC point at low temperature can be completed. Subsequently, the Arrhenius temperature extrapolation method (refer to step 140) is used to back-calculate the full-time-scale limit power value of that SOC point at room temperature and high temperature from the measured power value at low temperature. Power calibration of the entire SOC range can be completed without upgrading the high-current test equipment.

[0039] Step 120: Perform time extrapolation fitting based on multiple first limit power values ​​to obtain the first power-time relationship equation.

[0040] The time extrapolation fitting here refers to using the first limit power value within the existing observation range to establish a functional relationship (equation) of power changing with time through mathematical methods, so as to use this equation to predict or estimate the power value at future times (or unobserved time points) that are outside the existing observation range.

[0041] In one embodiment, step 120 may include: The power-time coordinate is obtained by taking the reciprocal of the first limiting power value as the vertical axis and the square root of the time corresponding to the first limiting power value as the horizontal axis. The first power-time relationship equation is obtained by linear fitting of multiple power-time coordinates.

[0042] Specifically, the power time coordinate is ( The power-time relationship equation is 1 / P = K· +B. Where K is the slope (characterizing the rate of change of diffusion impedance) and B is the intercept (characterizing the sum of ohmic impedance and charge transfer impedance). Based on the first power-time relationship equation, the limiting power value at any unmeasured time can be calculated outwards or inwards.

[0043] For example, the first parameter set is (T1, SOC1), and combined with the first limiting power value obtained above, it includes P. T1+SOC1 (t1), P T1+SOC1 (t2), P T1+SOC1 (t3), at this time the power time coordinate includes ( , 1 / P T1+SOC1 (t1)), ( , 1 / P T1+SOC1 (t2)), ( , 1 / P T1+SOC1 (t3)). By performing linear fitting based on these three power time coordinates, the slope K corresponding to (T1, SOC1) can be obtained. T1+SOC1 and intercept B T1+SOC1 Thus, the first power-time relationship equation is obtained as 1 / P=K. T1+SOC1 · +B T1+SOC1 .

[0044] For example, the first parameter set is (T2, SOC1), and combined with the first limiting power value obtained above, it includes P. T2+SOC1 (t1), P T2+SOC1 (t2), P T2+SOC1 (t3), at this time the power time coordinate includes ( , 1 / P T2+SOC1 (t1)), ( , 1 / P T2+SOC1 (t2)), ( , 1 / P T2+SOC1 (t3)). By performing linear fitting based on these three power time coordinates, the slope K corresponding to (T2, SOC1) can be obtained. T2+SOC1 and intercept B T2+SOC1 Thus, the first power-time relationship equation is obtained as 1 / P=K. T2+SOC1 · +B T2+SOC1 .

[0045] Similar to the process of fitting the first power-time relationship equation when the first parameter set is (T1, SOC1) or (T2, SOC1), the first power-time relationship equations with the first parameter set such as (T1, SOC2), (T1, SOC3), (T1, SOC4), (T2, SOC2), (T2, SOC3), and (T2, SOC4) can be obtained by fitting.

[0046] The advantage of the above embodiments is that, by utilizing the diffusion dynamics characteristics implied by the first limiting power values ​​at multiple moments under constant voltage pulse testing, the first power-time relationship equation can be fitted, making it convenient to obtain the power value at any unmeasured moment.

[0047] Step 130: Based on the power value obtained from the constant voltage pulse test and / or the power value calculated using the first power-time relationship equation, determine the second limit power value of the target battery at multiple test temperatures under the second parameter set.

[0048] The second parameter set includes a state of charge and a time. Multiple second parameter sets are obtained by combining multiple states of charge and multiple times in pairs. The second parameter set can be represented as (state of charge, time). For example, multiple second parameter sets include (SOC1, t1), (SOC1, t2), (SOC1, t3), (SOC2, t1), (SOC2, t2), (SOC2, t3), (SOC3, t1), (SOC3, t2), (SOC3, t3), (SOC4, t1), (SOC4, t2), (SOC4, t3).

[0049] For the second parameter set being (SOC1, t1) and multiple test temperatures including T1 and T2, the power value at t1 can be calculated based on the power values ​​obtained from the constant voltage pulse test at (T1, SOC1) and t1, and / or using the first power-time relationship equation of (T1, SOC1), thus obtaining the second limiting power value P corresponding to T1, SOC1, and t1. SOC1+t1 (T1); The power value at t1 can be calculated based on the power values ​​obtained from constant voltage pulse testing at (T2, SOC1) and t1, and / or using the first power-time relationship equation at (T2, SOC1), thus obtaining the second limiting power value P corresponding to T2, SOC1, and t1. SOC1+t1 (T2).

[0050] Similar to the process of obtaining the second limit power values ​​at multiple test temperatures (T1, T2) when the second parameter group is (SOC1, t1), the second limit power values ​​at multiple test temperatures under the second parameter group can be obtained as follows: (SOC1, t2), (SOC1, t3), (SOC2, t1), (SOC2, t2), (SOC2, t3), (SOC3, t1), (SOC3, t2), (SOC3, t3), (SOC4, t1), (SOC4, t2), (SOC4, t3).

[0051] Step 140: Perform temperature extrapolation fitting based on multiple second limit power values ​​to obtain the power-temperature relationship equation.

[0052] Temperature extrapolation fitting here refers to using the second limit power value within the existing observation range to establish a functional relationship (equation) between power and temperature through mathematical methods, so as to use this equation to predict or estimate the power value at temperatures outside the existing observation range (or unobserved temperatures).

[0053] In one embodiment, step 140 may include: The power-temperature coordinate system is obtained by taking the logarithm of the second limit power value as the ordinate and the reciprocal of the test temperature corresponding to the second limit power value as the abscissa. By performing linear fitting on multiple power-temperature coordinates, the power-temperature relationship equation is obtained.

[0054] Specifically, the power-temperature coordinate system is (1 / T, lnP), and the power-temperature relationship equation is lnP = A·(1 / T) + C. Here, A is the slope, and C is the intercept. Based on the power-temperature relationship equation, the limiting power value at any unmeasured temperature can be calculated outwards or inwards.

[0055] For example, the second parameter set is (SOC1, t1), which, combined with the second limiting power value obtained above, includes P. SOC1+t1 (T1), P SOC1+t1 (T2), at this time the power-temperature coordinates include (1 / T1, lnP) SOC1+t1 (T1)), (1 / T2, lnP) SOC1+t1 (T2)). By performing a linear fit based on these two power-time coordinates, the slope A corresponding to (SOC1, t1) can be obtained. SOC1+t1 and intercept C SOC1+t1 Thus, the power-temperature relationship equation is obtained as lnP=A SOC1+t1 ·(1 / T)+C SOC1+t1 .

[0056] Similar to the process of fitting the power-temperature relationship equation when the second parameter set is (SOC1, t1), we can obtain the power-temperature relationship equations with the second parameter set as (SOC1, t2), (SOC1, t3), (SOC2, t1), (SOC2, t2), (SOC2, t3), (SOC3, t1), (SOC3, t2), (SOC3, t3), (SOC4, t1), (SOC4, t2), and (SOC4, t3).

[0057] Step 150: Extract power based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value.

[0058] By utilizing the first power-time relationship equations of multiple first parameter groups, the power value at the unmeasured time of each first parameter group can be calculated without the need for constant voltage pulse testing across the entire time scale. Similarly, by utilizing the power-temperature relationship equations of multiple second parameter groups, the power value at the unmeasured temperature of each second parameter group can be calculated without the need for constant voltage pulse testing across the entire temperature scale. Therefore, this application leverages the natural decay characteristic of current under constant voltage pulse testing, requiring only a small amount of test data to extrapolate the ultimate power value covering the entire time, temperature, and state of charge, thus improving the efficiency and accuracy of battery power extraction.

[0059] In one embodiment, reference is made to Figure 2 Step 150 may include: Step 210: Calculate the power value using the first power-time relationship equation to obtain the extrapolated power values ​​for multiple unmeasured time points; Step 220: Calculate the power value using the power-temperature relationship equation to obtain extrapolated power values ​​for multiple unmeasured temperatures; Step 230: Based on the extrapolated power values ​​for all times and all extrapolated power values ​​for all temperatures, construct a power mapping table corresponding to temperature and state of charge at multiple time points. Step 240: Based on the current operating temperature and current state of charge of the target battery, query the power mapping table corresponding to the current operating time of the target battery to obtain the allowable limit power value.

[0060] In step 210, the extrapolated power values ​​for multiple unmeasured moments not within the pulse duration can be calculated using the first power-time relationship equation. This means that the extrapolated power values ​​for multiple unmeasured moments can be obtained when the first parameter set is (T1, any one of SOC1 to SOCn) or (T2, any one of SOC1 to SOCn). For example, for the case where the first parameter set is (T1, SOC1) and the multiple unmeasured moments include t4, t5, and t6, the first power-time relationship equation 1 / P=K for (T1, SOC1) can be used. T1+SOC1 · +B T1+SOC1 The extrapolated power values ​​P for time intervals t4, t5, and t6 are calculated. T1+SOC1 (t4), P T1+SOC1 (t5), P T1+SOC1 (t6).

[0061] In step 220, the extrapolated power values ​​for multiple unmeasured temperatures outside the test temperature range can be calculated using the power-temperature relationship equation. This means that the extrapolated power values ​​for multiple unmeasured temperatures can be obtained when the second parameter set is any one of SOC1 to SOCn and any one of t1 to tn. For example, for the case where the second parameter set is (SOC1, t1) and the multiple unmeasured temperatures include T3, T4, and T5, the power-temperature relationship equation lnP=A (SOC1, t1) can be used. SOC1+t1 ·(1 / T)+C SOC1+t1 The extrapolated power values ​​P for temperatures T3, T4, and T5 were calculated. SOC1+t1 (T3), P SOC1+t1 (T4), P SOC1+t1 (T5).

[0062] In step 230, based on all time extrapolated power values ​​and all temperature extrapolated power values, a full-scale limit power value set can be obtained. This full-scale limit power value set includes multiple limit power values ​​corresponding to temperature, state of charge, and time. The limit power values ​​corresponding to the same time in the full-scale limit power value set are grouped to obtain power mapping tables corresponding to temperature and state of charge at multiple times.

[0063] For example, based on the first limiting power values ​​at multiple moments (t1, t2, t3) within the pulse duration at the test temperature (T1, T2) and state of charge (SOC1 to SOCn), and the time-extrapolated power values ​​at multiple untested moments (t4 to tn), as well as the second limiting power values ​​at multiple test temperatures (T1, T2) and multiple untested temperatures (T3 to Tn) at the state of charge (SOC1 to SOCn) and moments (t1 to tn), the power values ​​corresponding to the state of charge (SOC1 to SOCn) and temperature (T1 to Tn) at each moment (t1 to tn) are extracted. This results in a two-dimensional "SOC-temperature" power map table for each moment (t1 to tn) and its corresponding power values, which is then stored in the battery management system. For instance, the power points for all SOC and temperature at conventional preset times (e.g., 5s, 10s, 30s, 60s) are extracted and multiple two-dimensional power maps are created.

[0064] In step 240, the power mapping table corresponding to the current operating time of the target battery is first located from multiple power mapping tables based on the current operating time of the target battery. Then, the power mapping table is queried based on the current operating temperature and current state of charge of the target battery to obtain the allowable limit power value. For example, under vehicle operating conditions, the battery management system obtains the allowable limit power value by directly consulting the two-dimensional power map table at the corresponding time.

[0065] The advantage of the above embodiments is that, based on the first power-time relationship equation and the power-temperature relationship equation, a power mapping table covering the entire SOC, temperature, and time scale can be generated, thereby improving the efficiency and accuracy of power extraction.

[0066] In one embodiment, reference is made to Figure 3 Step 150 may include: Step 310: Calculate the power value using the power-temperature relationship equation to obtain the extrapolated power value of the third parameter set at multiple times; wherein, the third parameter set includes an unmeasured temperature and a state of charge. Step 320: Perform time extrapolation fitting based on multiple temperature extrapolated power values ​​to obtain the second power-time relationship equation; Step 330: Take each first power time relationship equation and each second power time relationship equation as the target power time relationship equation; Step 340: Based on the slope in the target power time relationship equation, construct a slope mapping table corresponding to temperature and state of charge; based on the intercept in the target power time relationship equation, construct an intercept mapping table corresponding to temperature and state of charge. Step 350: Based on the current operating temperature and current state of charge of the target battery, query the slope mapping table to obtain the allowable power slope, and query the intercept mapping table to obtain the allowable power intercept. Based on the allowable power slope, allowable power intercept, and the current operating time of the target battery, calculate the allowable limit power value.

[0067] In step 310, for example, the power-temperature relationship equation for (SOC1, t1) is lnP=A SOC1+t1 ·(1 / T)+C SOC1+t1 The extrapolated power value P at temperature T3 can be calculated. SOC1+t1 (T3), thus obtaining the extrapolated power value P at temperature t1 when the third parameter set is (T3, SOC1). SOC1+t1 (T3). Similarly, the power-temperature relationship equation based on (SOC1, t2) is lnP=A SOC1+t2 ·(1 / T)+C SOC1+t2 The extrapolated power value P at temperature t2 when the third parameter set is (T3, SOC1) can be calculated. SOC1+t2 (T3). Similarly, the power-temperature relationship equation based on (SOC1, t3) is lnP=A SOC1+t3 ·(1 / T)+C SOC1+t3 The extrapolated power value P at temperature t3 when the third parameter set is (T3, SOC1) can be calculated. SOC1+t3 (T3).

[0068] It should be noted that in step 110, the first limiting power values ​​at multiple times under the first parameter group can be obtained. The temperatures in the first parameter group include T1 and T2, but not T3, T4, and T5. In step 310, based on the power-temperature relationship equation, the power value is extrapolated to the temperature at multiple times under the third parameter group, where the temperatures include T3, T4, and T5. Therefore, this application can obtain the corresponding limiting power values ​​without performing constant voltage pulse testing on the target battery under the third parameter group, thus improving testing efficiency.

[0069] In step 320, for example, the reciprocal of the extrapolated power value is used as the vertical axis, and the square root of the time corresponding to the extrapolated power value is used as the horizontal axis to obtain the extrapolated power time coordinate; a second power time relationship equation is obtained by linear fitting based on multiple extrapolated power time coordinates.

[0070] For example, the third parameter set is (T3, SOC1), and combined with the temperature extrapolation power value obtained above, it includes P. SOC1+t1 (T3), P SOC1+t2 (T3), P SOC1+t3 (T3), at this time the power time coordinate includes ( , 1 / P SOC1+t1 (T3) , 1 / P SOC1+t2 (T3) , 1 / P SOC1+t3 (T3)). By performing linear fitting based on these three extrapolated power time coordinates, the slope K corresponding to (T3, SOC1) can be obtained. T3+SOC1 and intercept B T3+SOC1 Thus, the second power-time relationship equation is obtained as 1 / P=K. T3+SOC1 · +B T3+SOC1 .

[0071] In step 330, each first power time relationship equation and each second power time relationship equation are used as target power time relationship equations, and target power time relationship equations covering the entire temperature (T1 to Tn) and the full state of charge (SOC to SOCn) can be obtained.

[0072] In step 340, the slope K and intercept B of the target power time relationship equations for each temperature and each state of charge are used as mapping matrix elements to construct a two-dimensional slope mapping table and a two-dimensional intercept mapping table for "SOC-temperature".

[0073] In step 350, for example under vehicle operating conditions, the battery power system determines the current allowable slope K in real time by looking up tables (including a two-dimensional slope mapping table and a two-dimensional intercept mapping table) based on the current operating state of charge and current operating temperature. allowable and the current allowable intercept B allowable Then obtain the current running time t of the battery power system control strategy as currently defined. current By using the formula 1 / P=K allowable · +B allowable Calculate the current running time t online in real time current The continuous dynamic allowable limit power value.

[0074] The advantage of the above embodiments is that it eliminates the need to store the limiting power values ​​at all times, all temperatures, and all states of charge. Instead, it stores slope mapping tables and intercept mapping tables corresponding to temperature and state of charge, thus saving storage resources.

[0075] In one embodiment, reference is made to Figure 4 Step 150 may include steps 310 to 330, and also includes steps 410 to 440.

[0076] Step 410: Perform temperature extrapolation fitting based on the slopes in multiple target power time relationship equations to obtain slope temperature relationship equations; Step 420: Perform temperature extrapolation fitting based on the intercepts in multiple target power time relationship equations to obtain the intercept temperature relationship equation; Step 430: Extract the power state parameters from the slope temperature relation equation and the intercept temperature relation equation, and construct a power state parameter mapping table corresponding to the state of charge based on the power state parameters. Step 440: Query the power state parameter mapping table according to the current state of charge of the target battery to obtain the allowable power state parameters. Calculate the allowable power slope and allowable power intercept based on the allowable power state parameters and the current operating temperature of the target battery. Calculate the allowable limit power value based on the allowable power slope, allowable power intercept, and the current operating time of the target battery.

[0077] In step 410, the logarithm (lnK) of the slope in the target power-time relationship equation corresponding to temperature and state of charge is used as the ordinate, and the reciprocal (1 / T) of the temperature corresponding to the target power-time relationship equation is used as the abscissa to obtain the slope-temperature coordinates (lnK, 1 / T). Linear fitting is performed on multiple slope-temperature coordinates for the same state of charge to obtain the slope-temperature relationship equation corresponding to the state of charge as lnK = k1·1 / T + b1. k1 represents the slope of the first state, and b1 represents the intercept of the first state.

[0078] In step 420, the logarithm (lnB) of the intercept in the target power-time relationship equation corresponding to temperature and state of charge is used as the ordinate, and the reciprocal (1 / T) of the temperature corresponding to the target power-time relationship equation is used as the abscissa to obtain the intercept temperature coordinate (lnB, 1 / T). Linear fitting is performed on multiple intercept temperature coordinates for the same state of charge to obtain the intercept temperature relationship equation corresponding to the state of charge as lnB = k2·1 / T + b2. K2 represents the slope of the second state, and b2 represents the intercept of the second state.

[0079] In step 430, the power state parameters for the charged state are obtained by combining the first-state slope and first-state intercept in the slope-temperature relationship equation corresponding to the charged state, and the second-state slope and second-state intercept in the intercept-temperature relationship equation corresponding to the charged state. A power state parameter mapping table corresponding to the charged state is then constructed based on the power state parameters for all charged states.

[0080] For example, after obtaining the slope K and intercept B of the target power-time relationship equations for different states of charge and temperatures, the responses of K and B at different temperatures are further extrapolated and fitted based on the Arrhenius equation. The fitted equations are: lnK = k1·1 / T + b1 and lnB = k2·1 / T + b2. Based on the above two equations, the power state parameters (including k1, b1, k2, and b2) for each state of charge are extracted, and a power state parameter mapping table that varies with the state of charge is constructed.

[0081] In step 440, for example in vehicle-mounted conditions, the battery management system determines the allowable power state parameters (including k1) by consulting the power state parameter mapping table based on the current state of charge of the target battery. allowable b1 allowable k2 allowable b2 allowable ), and combined with the current operating temperature T current Calculate the allowable power slope K allowable =k1 allowable ·1 / T current +b1 allowable and allowable power intercept B allowable =k1 allowable ·1 / T current +b1 allowable Finally, based on the current running time t current And formula 1 / P=K allowable · +B allowable Calculate the current allowable power limit value.

[0082] The advantage of the above embodiments is that instead of storing a two-dimensional table, a one-dimensional table corresponding to the state of charge (i.e., a power state parameter mapping table) is stored, which further saves storage resources and improves query efficiency.

[0083] In the first example, a ternary lithium-ion battery cell with a nominal capacity of 100Ah is used as the target battery to fully demonstrate the entire process of extracting maximum power across all states of charge (SOC), temperatures, and time scales. The target battery's discharge cutoff voltage is 2.8V, and its charging cutoff voltage is 4.4V. The battery power extraction method may include the following steps: 1. Test environment preparation: Place the target battery in a high and low temperature control chamber and select two test temperatures, T1=0℃ and T2=15℃, to conduct the test; after the temperature control chamber temperature stabilizes, let the target battery stand for no less than 2 hours to ensure that the temperature of the target battery body is consistent with the ambient temperature.

[0084] 2. SOC Adjustment: The target battery is adjusted to a specific SOC using a standard charge and discharge procedure. The SOC test points are set to 0%, 10%, 20%, ..., 100%, for a total of 11 test points. After each SOC adjustment, the cell is left to stand for 120 minutes to ensure the stability of the internal electrochemical state.

[0085] 3. Constant voltage pulse loading: Apply constant voltage pulse discharge to the target battery to clamp the battery voltage to the discharge cutoff voltage of 2.8V (safe voltage lower limit). The pulse duration is 60s, and the current decay curve I(t) during the pulse duration is collected. Constant voltage pulse charging uses the same model of three-electrode cell for pre-calibration: at the corresponding SOC and temperature, the total voltage at the battery terminal when the negative electrode potential drops to 0V (lithium plating critical point) (e.g., the battery terminal voltage at 20% SOC at 15℃ is 3.41V). This current voltage is used as the constant voltage pulse clamping threshold to ensure that the charging limit power obtained by the test corresponds exactly to the lithium plating risk critical point of the cell, avoiding the redundancy of lithium plating risk or underestimation of power caused by testing with the cutoff voltage.

[0086] 4. Calculation of the first limiting power value: Since the constant voltage V remains constant throughout the pulse duration, the first limiting power value at any time t is: P_measured(t) = I(t) × V. Taking the discharge condition of 0℃ and 50% SOC as an example, the current and corresponding power at typical times are as follows: When t1 = 5s, the discharge current I = 1361.7A, and the first limiting power P_5s = 1361.7A × 2.8V = 3812W; when t2 = 10s, the discharge current I = 1173.3A, and the first limiting power P_10s = 1173.3A × 2.8V = 3284W; when t3 = 30s, the discharge current I = 917A, and the first limiting power P_30s = 917A × 2.8V = 2567W.

[0087] 5. Time-dimensional extrapolation (based on Cottrell diffusion kinetics): Under constant voltage pulses, the cell current decay is dominated by the lithium-ion diffusion process inside the electrode, strictly following the Cottrell equation, which is expressed as the reciprocal of power 1 / P and the square root of time. The relationship is linear. The corresponding coordinate values ​​for the first limiting power value at 0℃ and 50% SOC are shown in Table 1.

[0088] Table 1

[0089] by Using least-squares linear fitting with K as the x-axis and 1 / P as the y-axis, the power-time relationship equation is obtained: 1 / P = K· +B. The fitting yielded a slope K = 3.87 × 10⁻⁶ for this working condition. -5 W -1 ·s -1 / 2 Intercept B = 1.78 × 10 -4 W -1 The goodness of fit R²≈0.997 verified the accuracy of the linear relationship.

[0090] For example, extrapolating the short-time limiting power at t=15s: ≈3.873, substituting, we get 1 / P = 3.87 × 10 -5 ×3.873+1.78×10 -4 =3.28×10 -4 This corresponds to P_15s≈3045W. Extrapolating the long-term limiting power at t=60s: ≈7.746, substituting, we get 1 / P = 3.87 × 10 -5 ×7.746+1.78×10 -4 =4.78×10 -4 The corresponding value is P_60s≈2090W.

[0091] Based on the above method, the K and B parameters corresponding to all SOC test points can be obtained in a single temperature test.

[0092] 6. Temperature Dimension Extrapolation (Based on Arrhenius Thermal Activation Mechanism): The temperature response of battery power is dominated by the thermal activation characteristics of electrochemical reactions, following Arrhenius's law, which shows that the logarithm of power lnP is linearly related to the reciprocal of thermodynamic temperature 1 / T.

[0093] Taking a constant voltage pulse discharge with a state of charge (SOC) of 30% and a t=10s as an example, the power values ​​at two test temperatures are extracted: T1=0℃=273.15K, corresponding to a power P1=2531W, lnP1≈7.8364, 1 / T1≈0.003661K. -1T2 = 15℃ = 288.15K, corresponding power P2 = 5243W, lnP2 ≈ 8.5646, 1 / T2 ≈ 0.003470K -1 Based on linear fitting of (0.003661, 7.8364) and (0.003470, 8.5646), the temperature slope A≈-3821.44K and the temperature intercept C≈21.83 are obtained. Therefore, the power-temperature relationship equation is lnP=-3821.44·(1 / T)+21.83.

[0094] Temperature extrapolation is performed based on the power-temperature relationship equation. For example, the 10-second discharge limit power at -20℃ (253.15K) is calculated as follows: 1 / T = 0.003950K. -1 Substituting this into the equation, we get lnP = 6.7311, corresponding to P ≈ 838.05 W. Alternatively, based on the K and B values ​​under different SOCs, a linear fit can be performed on the temperature, showing a linear relationship between the logarithm of the parameters and the reciprocal of the temperature. This allows us to derive the temperature fitting equation for the K and B values.

[0095] Taking a discharge power of 20% SOC and t=10s as an example: T1=0℃=273.15K, corresponding to K=1.44×10 -4 W -1 ·s -1 / 2 B = 2.03 × 10 -4 W -1 , lnK≈-6.5023, lnB≈-5.2591, 1 / T1≈0.003661K -1 T2 = 15℃ = 288.15K, corresponding to K = 5.42 × 10⁻⁶. 5 W -1 ·s -1 / 2 B = 1.2 × 10 4 W -1 , lnK≈-7.3385, lnB≈-5.8781, 1 / T2≈0.003470K -1 Linear fitting was performed with 1 / T as the abscissa and lnK and lnB as the ordinates, respectively, to obtain the slope-temperature relationship equation and the intercept-temperature relationship equation: lnK=k1·(1 / T)+b1; lnB=k2·(1 / T)+b2. The fitted values ​​for this SOC were k1≈4387.97K; k2≈3248.23K, b1≈-22.57; b2≈-17.15.

[0096] Based on the slope-temperature relationship equation and the intercept-temperature relationship equation, temperature extrapolation was performed, and the calculated K value for a SOC of 20% at -20℃ was 5.32 × 10⁻⁶. -3 W -1 ·s -1 / 2 B = 1.33 × 10-2 W -1 Furthermore, the power P_30s = 23.56W can be calculated for 30s.

[0097] By employing the aforementioned process of single constant-voltage pulse testing + time extrapolation + temperature extrapolation, a minimum of only 2 temperature points, 11 SOC points, and a single 60-second constant-voltage pulse can cover the entire temperature range of -40℃ to 55℃, the entire SOC range of 0% to 100%, and the entire time scale of 1s to 100s, providing a limit power database. The testing cycle is shortened by more than 85% compared to the traditional HPPC method. In actual experiments, a temperature testing group can be added to improve the accuracy of the temperature fitting equation.

[0098] In the second example (full-scale discrete table-based BMS power control strategy), a two-dimensional power table (including power mapping tables corresponding to temperature and state of charge at multiple time points) is constructed: Based on the full-scale limit power database obtained in the first example, a discrete power map table adapted to low-end battery management system chips is constructed, compatible with the lookup logic of traditional battery management systems. From the full-scale limit power database, commonly used pulse times (5s, 10s, 30s, 60s) for automotive scenarios are extracted, and a two-dimensional discharge / charge power table of "temperature-SOC" is constructed for each time dimension. The table temperature range is set to -40℃ to 55℃, with 5℃ intervals, for a total of 20 temperature nodes; the SOC range is 0% to 100%, with 5% intervals, for a total of 21 SOC nodes. Taking the 5s discharge power table as an example, the table format is shown in Table 2.

[0099] Table 2

[0100] Battery Management System Online Table Lookup Process: (1) Real-time acquisition of the voltage, current and temperature of the target battery, and obtaining the current SOC through the SOC estimation algorithm; (2) Receiving the power request from the vehicle controller, obtaining the target pulse duration, and matching the closest discrete time dimension power mapping table; (3) Based on the current operating temperature and the current SOC, using the bilinear interpolation algorithm in the corresponding power mapping table to calculate the limit charge and discharge power under the current operating conditions; (4) After boundary correction in combination with battery overvoltage, undervoltage, overcurrent and other safety constraints, the final allowable limit power value is output to the vehicle controller.

[0101] In the third example (time-dimensional parameterized BMS power control strategy), a two-dimensional parameter table is constructed: To eliminate storage redundancy in discrete-time tables and achieve online power calculation at arbitrary time scales, this example parameterizes the power characteristics in the time dimension, constructing a two-dimensional parameter map table based on the dynamic parameters K and B. Based on the K and B parameters fitted in the first example for each operating condition, a two-dimensional slope mapping table and a two-dimensional intercept mapping table (collectively referred to as a set of parameter tables) of "temperature-SOC" are constructed respectively. The table format is shown in Table 3.

[0102] Table 3

[0103] The battery management system online calculation process is as follows: (1) Real-time acquisition of the target battery temperature and current SOC, and receiving the target duration t of the vehicle power request; (2) Based on the current operating temperature and current SOC, bilinear interpolation is performed in the slope and intercept two-dimensional parameter tables to obtain the dynamic parameters K and B under the current operating conditions; (3) Substituting into the power-time relationship equation, the limit power is calculated in real time: P=1 / (K· +B); (4) After the safety boundary constraint correction, output the final allowable limit power.

[0104] In the fourth example (Time-Temperature Dual-Parameterized SOC Single-Table BMS Power Control Strategy), to maximize storage space compression and adapt to resource-constrained BMS chips or high-resolution parameter scenarios, this example further parameterizes the temperature-dimensional response characteristics, constructing a power state parameter mapping table that only varies with the SOC in one dimension. One-dimensional SOC parameter table construction: For each SOC, the K and B values ​​at different temperatures are linearly fitted based on the Arrhenius equation, yielding: ln K = k1·(1 / T) + b1 and ln B = k2·(1 / T) + b2. For each SOC, the above four power state parameters are stored, constructing a one-dimensional mapping table that only varies with the SOC, as shown in Table 4.

[0105]

[0106] The complete online calculation process of the battery management system is as follows: (1) Real-time acquisition of the current state of charge of the battery cell and the thermodynamic temperature T of the single cell, and receiving the target duration t of the power request of the whole vehicle; (2) Based on the current state of charge, linear interpolation is performed in the one-dimensional parameter table to obtain the four power state parameters corresponding to the current state of charge, namely k1, b1, k2, and b2; (3) Substitute into the Arrhenius equation to calculate the dynamic parameters K and B at the current temperature: K=exp(k1 / T+b1), B=exp(k2 / T+b2); (4) Substitute into the power-time relationship equation to calculate the limit power under the current operating condition: P=1 / (K· +B); (5) After combining the cell voltage and current safety thresholds for boundary constraints, output the final allowable limit power.

[0107] Storage resource quantification comparison: Taking 21 SOC nodes and 20 temperature nodes as examples, the storage resource and space quantification comparison analysis of the three strategies is shown in Table 5.

[0108] Table 5

[0109] This application can achieve the following technical effects: 1. Improved testing efficiency: Traditional HPPC constant current pulse tests require multiple discrete tests at different times. However, this application utilizes the natural decay of current under constant voltage pulse testing to capture all the ultimate power characteristics across the entire time scale from short to long time with a single constant voltage pulse test, reducing the testing workload and cycle by more than 80%.

[0110] 2. Rigorous physical extrapolation with extremely high full-scale accuracy: This application does not rely on blind mathematical fitting, but is based on standard electrochemical mechanisms. The current decay under constant voltage pulse testing strictly follows the Cottrell characteristic, manifested as 1 / P and The linearity of the time and temperature response is highly linear, while the temperature response follows the Arrhenius thermal activation energy law. This ensures that the application maintains extremely high accuracy even when extrapolating over a wide range of time and temperature dimensions.

[0111] 3. Revolutionary Release of Battery Management System Storage Space (Extremely Simplified Storage): Compared to Strategy 1 (steps 210 to 240), which still requires storing multiple discrete-time two-dimensional tables, Strategy 2 (steps 310 to 350) condenses and compresses the power tables of arbitrary time dimensions into a single two-dimensional table concerning K and B, achieving continuous, stepless online calculation of time-scale variations. Strategy 3 (steps 310 to 330 and 410 to 440) goes a step further, parameterizing both time and temperature dimensions, compressing the originally massive high-dimensional database into a single one-dimensional power state parameter mapping table. This significantly frees up the Flash memory space of the battery management system.

[0112] Please see Figure 5 This application also provides a battery power extraction device that can implement the above-described battery power extraction method. The battery power extraction device includes: The first power acquisition module 510 is used to perform a constant voltage pulse test on the target battery under a first parameter set to obtain a first limit power value at multiple moments within the pulse duration; wherein, the first parameter set includes a test temperature and a state of charge; The time extrapolation fitting module 520 is used to perform time extrapolation fitting based on multiple first limit power values ​​to obtain the first power-time relationship equation; The second power acquisition module 530 is used to determine the second limit power value of the target battery at multiple test temperatures under the second parameter set based on the power value obtained from the constant voltage pulse test and / or the power value calculated using the first power-time relationship equation; wherein the second parameter set includes a state of charge and a time. The temperature extrapolation and fitting module 540 is used to perform temperature extrapolation and fitting based on multiple second limit power values ​​to obtain the power-temperature relationship equation. The power extraction module 550 is used to extract power based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value.

[0113] This application also provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the above-described battery power extraction method. This electronic device can be any smart terminal, including tablet computers, in-vehicle computers, etc.

[0114] Please see Figure 6 , Figure 6 The hardware structure of an electronic device according to another embodiment is illustrated. The electronic device includes: The processor 610 can be implemented using a general-purpose central processing unit (CPU), microprocessor, application specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this application. The memory 620 can be implemented as a read-only memory (ROM), static storage device, dynamic storage device, or random access memory (RAM). The memory 620 can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory 620 and called and executed by the processor 610 to execute the battery power extraction method of the embodiments of this application. The input / output interface 630 is used to realize information input and output; The communication interface 640 is used to enable communication and interaction between this device and other devices. Communication can be achieved through wired means (such as USB, network cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.). Bus 550 transmits information between various components of the device (e.g., processor 610, memory 620, input / output interface 630, and communication interface 640); The processor 610, memory 620, input / output interface 630 and communication interface 640 are connected to each other within the device via bus 650.

[0115] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described battery power extraction method.

[0116] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0117] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0118] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0119] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0120] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0121] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0122] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0123] In the several 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 the units described above 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 system, 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 apparatuses or units may be electrical, mechanical, or other forms.

[0124] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0125] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0126] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes multiple instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing programs, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0127] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A method for extracting battery power, characterized in that, The method includes: A constant voltage pulse test is performed on the target battery under a first set of parameters to obtain a first limit power value at multiple moments within the pulse duration; wherein, the first set of parameters includes a test temperature and a state of charge, and the first limit power value is obtained under the extreme condition of maintaining the potential of the target battery at a safe threshold boundary; The first power-time relationship equation is obtained by extrapolating and fitting multiple first limit power values ​​over time. Based on the power value obtained from the constant voltage pulse test and / or the power value calculated using the first power-time relationship equation, a second limit power value for the target battery at multiple test temperatures under the second parameter set is determined; wherein, the second parameter set includes a state of charge and a time. By performing temperature extrapolation fitting based on multiple second limit power values, a power-temperature relationship equation is obtained. Power is extracted based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value.

2. The method according to claim 1, characterized in that, The step of extracting power based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value includes: By using the first power-time relationship equation, power values ​​are extrapolated to obtain time-extrapolated power values ​​for multiple unmeasured time points; By using the power-temperature relationship equation, power values ​​are extrapolated to obtain power values ​​for multiple unmeasured temperatures. Based on all the time extrapolated power values ​​and all the temperature extrapolated power values, a power mapping table corresponding to temperature and state of charge at multiple time points is constructed. The allowable power limit value is obtained by querying the power mapping table corresponding to the current operating time of the target battery based on the current operating temperature and current state of charge of the target battery.

3. The method according to claim 1, characterized in that, The step of extracting power based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value includes: The power-temperature relationship equation is used to extrapolate the power value, and the extrapolated power value of the third parameter set at multiple times is obtained; wherein, the third parameter set includes an unmeasured temperature and a state of charge; A second power-time relationship equation is obtained by performing time extrapolation fitting based on multiple temperature extrapolation power values; Each of the first power time relationship equations and each of the second power time relationship equations are taken as the target power time relationship equations; Based on the slope in the target power time relationship equation, a slope mapping table corresponding to temperature and state of charge is constructed; based on the intercept in the target power time relationship equation, an intercept mapping table corresponding to temperature and state of charge is constructed. The allowable power slope is obtained by querying the slope mapping table based on the current operating temperature and current state of charge of the target battery, and the allowable power intercept is obtained by querying the intercept mapping table. The allowable power limit value is calculated based on the allowable power slope, the allowable power intercept, and the current operating time of the target battery.

4. The method according to claim 3, characterized in that, The step of extracting power based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value further includes: Temperature extrapolation fitting is performed based on the slopes in multiple target power time relationship equations to obtain slope temperature relationship equations; Temperature extrapolation fitting is performed based on the intercepts in multiple target power time relationship equations to obtain intercept temperature relationship equations; Power state parameters are extracted from the slope temperature relation equation and the intercept temperature relation equation, and a power state parameter mapping table corresponding to the state of charge is constructed based on the power state parameters. The allowable power state parameters are obtained by querying the power state parameter mapping table based on the current state of charge of the target battery. The allowable power slope and allowable power intercept are calculated based on the allowable power state parameters and the current operating temperature of the target battery. The allowable limit power value is calculated based on the allowable power slope, the allowable power intercept, and the current operating time of the target battery.

5. The method according to any one of claims 1 to 4, characterized in that, The step of performing time extrapolation fitting based on multiple first limiting power values ​​to obtain the first power-time relationship equation includes: The power-time coordinate is obtained by taking the reciprocal of the first limiting power value as the vertical axis and the square root of the time corresponding to the first limiting power value as the horizontal axis. The first power-time relationship equation is obtained by linear fitting based on multiple power-time coordinates.

6. The method according to any one of claims 1 to 4, characterized in that, The step of performing temperature extrapolation fitting based on multiple second-limit power values ​​to obtain the power-temperature relationship equation as a function of power and temperature includes: The power-temperature coordinate is obtained by taking the logarithm of the second limit power value as the vertical axis and the reciprocal of the test temperature corresponding to the second limit power value as the horizontal axis. The power-temperature relationship equation is obtained by linear fitting of multiple power-temperature coordinates.

7. The method according to any one of claims 1 to 4, characterized in that, The constant voltage pulse test is performed on the target battery under the first parameter set to obtain the first limit power value at multiple moments within the pulse duration, including: Under the first parameter set, a constant voltage pulse test is performed on the target battery according to the constant voltage potential to obtain the measured current decay curve within the pulse duration. The current at multiple moments in the measured current decay curve is multiplied by the constant voltage potential to obtain the first limit power value at multiple moments.

8. A battery power extraction device, characterized in that, The device includes: The first power acquisition module is used to perform a constant voltage pulse test on the target battery under a first parameter set to obtain a first limit power value at multiple moments within the pulse duration; wherein, the first parameter set includes a test temperature and a state of charge, and the first limit power value is obtained under the extreme condition of maintaining the potential of the target battery at a safe threshold boundary; The time extrapolation fitting module is used to perform time extrapolation fitting based on multiple first limit power values ​​to obtain a first power-time relationship equation. The second power acquisition module is used to determine the second limit power value of the target battery at multiple test temperatures under the second parameter set based on the power value obtained from the constant voltage pulse test and / or the power value calculated using the first power-time relationship equation; wherein the second parameter set includes a state of charge and a time. The temperature extrapolation and fitting module is used to perform temperature extrapolation and fitting based on multiple second limit power values ​​to obtain a power-temperature relationship equation. The power extraction module is used to extract power based on the first power-time relationship equation and the power-temperature relationship equation to obtain the allowable limit power value.

9. An electronic device, characterized in that, The electronic device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the method according to any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the method described in any one of claims 1 to 7.

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