Method and device for obtaining battery model parameters, computer device and storage medium

Abstract

The application relates to a battery model parameter acquisition method and device, computer equipment, a storage medium and a computer program product. The method comprises the following steps: obtaining test curves by testing a target battery at different temperatures through a charging and discharging device, and determining the target test curves corresponding to each temperature. For each temperature, the curve slope of the target test curve corresponding to the temperature is identified to obtain curve slope data. For each temperature, the state of charge interval is determined based on the curve slope data. The pulse time for pulse testing is obtained based on the state of charge interval to determine the voltage change curve. Based on the voltage change curves corresponding to each temperature, parameter fitting is performed through a pre-constructed equivalent circuit model to obtain the parameters of the battery model corresponding to the target battery. In this way, the accuracy of the battery model parameters is greatly improved.

Description

Technical Field

[0001] This application relates to the field of new energy battery technology, and in particular to a method, apparatus, computer device, storage medium and computer program product for obtaining battery model parameters. Background Technology

[0002] With the development of new energy battery technology, simulation modeling is required to evaluate battery performance. This modeling process necessitates obtaining the parameters of the battery model.

[0003] In traditional technologies, HPPC (Hybrid Pulse Power Characterization) testing is used to obtain parameters of a battery model. However, to save testing time, HPPC often collects data at the same SOC (State of Charge) intervals. This results in insufficient data collection, making it impossible to accurately obtain the battery model's parameters and significantly reducing the accuracy of parameter acquisition. Summary of the Invention

[0004] Therefore, it is necessary to provide a method, apparatus, computer device, computer-readable storage medium, and computer program product for obtaining battery model parameters to address the aforementioned technical problems.

[0005] Firstly, this application provides a method for obtaining battery model parameters. The method includes:

[0006] Based on the test curves obtained by performing multiple tests on the target battery at different temperatures using a charge-discharge device, the target test curves corresponding to each temperature are determined; wherein, the target test curves characterize the changes in voltage with charge state during the test process;

[0007] For each temperature, the slope of the target test curve corresponding to the corresponding temperature is identified to obtain the slope data of the target test curve at the corresponding temperature.

[0008] For each temperature, based on the slope data of the curve corresponding to the target test curve at the corresponding temperature, the charge state interval corresponding to the target test curve at the corresponding temperature is determined, wherein the charge state interval characterizes the adjustment value of the charge state during the pulse test;

[0009] For each temperature, multiple pulse currents corresponding to the corresponding temperature are determined, and based on the charge state interval and pulse current corresponding to the target test curve at the corresponding temperature, the pulse time at the corresponding temperature is determined. The pulse time is used to instruct the charging and discharging device to perform pulse testing.

[0010] Obtain voltage change curves corresponding to various temperatures obtained by pulse testing of the target battery based on the pulse time using a charge-discharge device; the voltage change curves characterize the change of voltage with pulse current and time.

[0011] Based on the voltage change curves corresponding to each temperature, parameters are fitted using a pre-constructed equivalent circuit model to obtain the parameters of the battery model corresponding to the target battery.

[0012] Secondly, this application also provides a device for obtaining battery model parameters. The device includes:

[0013] Based on the test curves obtained by performing multiple tests on the target battery at different temperatures using a charge-discharge device, the target test curves corresponding to each temperature are determined; wherein, the target test curves characterize the changes in voltage with charge state during the test process;

[0014] For each temperature, the slope of the target test curve corresponding to the corresponding temperature is identified to obtain the slope data of the target test curve at the corresponding temperature.

[0015] For each temperature, based on the slope data of the curve corresponding to the target test curve at the corresponding temperature, the charge state interval corresponding to the target test curve at the corresponding temperature is determined, wherein the charge state interval characterizes the adjustment value of the charge state during the pulse test;

[0016] For each temperature, multiple pulse currents corresponding to the corresponding temperature are determined, and based on the charge state interval and pulse current corresponding to the target test curve at the corresponding temperature, the pulse time at the corresponding temperature is determined. The pulse time is used to instruct the charging and discharging device to perform pulse testing.

[0017] Obtain voltage change curves corresponding to various temperatures obtained by pulse testing of the target battery based on the pulse time using a charge-discharge device; the voltage change curves characterize the change of voltage with pulse current and time.

[0018] Based on the voltage change curves corresponding to each temperature, parameters are fitted using a pre-constructed equivalent circuit model to obtain the parameters of the battery model corresponding to the target battery.

[0019] Thirdly, this application also provides a computer device. The computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to perform the following steps:

[0020] Based on the test curves obtained by performing multiple tests on the target battery at different temperatures using a charge-discharge device, the target test curves corresponding to each temperature are determined; wherein, the target test curves characterize the changes in voltage with charge state during the test process;

[0021] For each temperature, the slope of the target test curve corresponding to the corresponding temperature is identified to obtain the slope data of the target test curve at the corresponding temperature.

[0022] For each temperature, based on the slope data of the curve corresponding to the target test curve at the corresponding temperature, the charge state interval corresponding to the target test curve at the corresponding temperature is determined, wherein the charge state interval characterizes the adjustment value of the charge state during the pulse test;

[0023] For each temperature, multiple pulse currents corresponding to the corresponding temperature are determined, and based on the charge state interval and pulse current corresponding to the target test curve at the corresponding temperature, the pulse time at the corresponding temperature is determined. The pulse time is used to instruct the charging and discharging device to perform pulse testing.

[0024] Obtain voltage change curves corresponding to various temperatures obtained by pulse testing of the target battery based on the pulse time using a charge-discharge device; the voltage change curves characterize the change of voltage with pulse current and time.

[0025] Based on the voltage change curves corresponding to each temperature, parameters are fitted using a pre-constructed equivalent circuit model to obtain the parameters of the battery model corresponding to the target battery.

[0026] Fourthly, this application also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program thereon, which, when executed by a processor, performs the following steps:

[0027] Based on the test curves obtained by performing multiple tests on the target battery at different temperatures using a charge-discharge device, the target test curves corresponding to each temperature are determined; wherein, the target test curves characterize the changes in voltage with charge state during the test process;

[0028] For each temperature, the slope of the target test curve corresponding to the corresponding temperature is identified to obtain the slope data of the target test curve at the corresponding temperature.

[0029] For each temperature, based on the slope data of the curve corresponding to the target test curve at the corresponding temperature, the charge state interval corresponding to the target test curve at the corresponding temperature is determined, wherein the charge state interval characterizes the adjustment value of the charge state during the pulse test;

[0030] For each temperature, multiple pulse currents corresponding to the corresponding temperature are determined, and based on the charge state interval and pulse current corresponding to the target test curve at the corresponding temperature, the pulse time at the corresponding temperature is determined. The pulse time is used to instruct the charging and discharging device to perform pulse testing.

[0031] Obtain voltage change curves corresponding to various temperatures obtained by pulse testing of the target battery based on the pulse time using a charge-discharge device; the voltage change curves characterize the change of voltage with pulse current and time.

[0032] Based on the voltage change curves corresponding to each temperature, parameters are fitted using a pre-constructed equivalent circuit model to obtain the parameters of the battery model corresponding to the target battery.

[0033] Fifthly, this application also provides a computer program product. The computer program product includes a computer program that, when executed by a processor, performs the following steps:

[0034] Based on the test curves obtained by performing multiple tests on the target battery at different temperatures using a charge-discharge device, the target test curves corresponding to each temperature are determined; wherein, the target test curves characterize the changes in voltage with charge state during the test process;

[0035] For each temperature, the slope of the target test curve corresponding to the corresponding temperature is identified to obtain the slope data of the target test curve at the corresponding temperature.

[0036] For each temperature, based on the slope data of the curve corresponding to the target test curve at the corresponding temperature, the charge state interval corresponding to the target test curve at the corresponding temperature is determined, wherein the charge state interval characterizes the adjustment value of the charge state during the pulse test;

[0037] For each temperature, multiple pulse currents corresponding to the corresponding temperature are determined, and based on the charge state interval and pulse current corresponding to the target test curve at the corresponding temperature, the pulse time at the corresponding temperature is determined. The pulse time is used to instruct the charging and discharging device to perform pulse testing.

[0038] Obtain voltage change curves corresponding to various temperatures obtained by pulse testing of the target battery based on the pulse time using a charge-discharge device; the voltage change curves characterize the change of voltage with pulse current and time.

[0039] Based on the voltage change curves corresponding to each temperature, parameters are fitted using a pre-constructed equivalent circuit model to obtain the parameters of the battery model corresponding to the target battery.

[0040] The aforementioned battery model parameter acquisition method, apparatus, computer equipment, storage medium, and computer program product obtain test curves by performing multiple tests on the target battery at different temperatures using a charge-discharge device. This allows for the determination of highly accurate and realistic target test curves for each temperature from these multiple tests; these target test curves characterize the voltage variation with charge state during the test. For each temperature, the slope of the target test curve corresponding to that temperature is identified, yielding the slope data for that temperature. This clearly reflects whether the curve changes smoothly during charge and discharge. For each temperature, based on the slope data of the target test curve at that temperature, the charge state interval corresponding to that temperature is determined. This charge state interval characterizes the adjustment value of the charge state during pulse testing. Thus, based on the curve changes characterized by the target test curve, the adjustment value of the charge state matching the curve changes can be quickly and effectively determined, significantly saving time in subsequent parameter determination processes. For each temperature, multiple pulse currents corresponding to that temperature are determined. Based on the charge state interval and pulse current corresponding to the target test curve at that temperature, the pulse time at that temperature is determined. This pulse time is used to instruct the charge / discharge device to perform pulse testing. This allows for real-time reflection of the pulse time used for pulse testing. Voltage change curves corresponding to each temperature are obtained after pulse testing of the target battery by the charge / discharge device based on these pulse times. These voltage change curves characterize the voltage change with pulse current and time. Based on these voltage change curves corresponding to each temperature, parameters are fitted using a pre-built equivalent circuit model to obtain the parameters of the battery model corresponding to the target battery. This allows for the acquisition of highly accurate battery model parameters while saving time, significantly increasing the accuracy of the battery model parameters. Attached Figure Description

[0041] Figure 1 This is an application environment diagram of a method for obtaining battery model parameters in one embodiment;

[0042] Figure 2 This is a flowchart illustrating a method for obtaining battery model parameters in one embodiment;

[0043] Figure 3 This is a schematic diagram of the target discharge curve in one embodiment;

[0044] Figure 4 This is a schematic diagram of the pulse current, charge state, and voltage curves in one embodiment;

[0045] Figure 5 This is a schematic diagram of an equivalent circuit model in one embodiment;

[0046] Figure 6 This is a flowchart illustrating the steps for determining the target test curve in one embodiment;

[0047] Figure 7 This is a flowchart illustrating the steps for determining curve slope data in one embodiment;

[0048] Figure 8 This is a schematic diagram of the first derivative curve in one embodiment;

[0049] Figure 9 This is a schematic diagram comparing experimental data in one embodiment;

[0050] Figure 10 This is a structural block diagram of a device for acquiring battery model parameters in one embodiment;

[0051] Figure 11 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0052] 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.

[0053] The method for obtaining battery model parameters provided in this application embodiment can be applied to, for example... Figure 1In the application environment shown, the charging / discharging device 102 communicates with the computer device 104 via a network. A data storage system can store the data that the computer device 104 needs to process. The data storage system can be integrated into the computer device 104 or placed in the cloud or on another network server. Based on the test curves obtained by the charging / discharging device 102 performing multiple tests on the target battery at different temperatures, the computer device 104 determines the target test curve corresponding to each temperature; wherein, the target test curve characterizes the change of voltage with charge state during the test. For each temperature, the computer device 104 identifies the slope of the target test curve corresponding to the corresponding temperature, obtaining the slope data of the curve corresponding to the target test curve at the corresponding temperature. For each temperature, based on the slope data of the curve corresponding to the target test curve at the corresponding temperature, the computer device 104 determines the charge state interval corresponding to the target test curve at the corresponding temperature, wherein, the charge state interval characterizes the adjustment value of the charge state during the pulse test. For each temperature, multiple pulse currents corresponding to that temperature are determined. Based on the charge state interval and pulse current corresponding to the target test curve at that temperature, the pulse time at that temperature is determined. This pulse time is used to instruct the charging / discharging device 102 to perform pulse testing. The computer device 104 acquires the voltage change curves corresponding to each temperature obtained by the charging / discharging device 102 performing pulse testing on the target battery based on the pulse time. These voltage change curves characterize the voltage change with pulse current and time. Based on these voltage change curves corresponding to each temperature, the computer device 104 performs parameter fitting through a pre-built equivalent circuit model to obtain the parameters of the battery model corresponding to the target battery. The charging / discharging device 102 can be an electronic measuring device with charging and discharging functions. The computer device 104 can be a terminal or a server. The terminal can be, but is not limited to, various personal computers, laptops, smartphones, tablets, IoT devices, and portable wearable devices. IoT devices can be smart speakers, smart TVs, smart air conditioners, smart in-vehicle devices, etc. Portable wearable devices can be smartwatches, smart bracelets, head-mounted devices, etc. A server can be implemented using a standalone server or a server cluster consisting of multiple servers.

[0054] In one embodiment, such as Figure 2 As shown, a method for obtaining battery model parameters is provided, and this method is applied to... Figure 1 Taking a computer device as an example, the explanation includes the following steps:

[0055] Step S202: Based on the test curves obtained by performing multiple tests on the target battery at different temperatures using a charge-discharge device, determine the target test curves corresponding to each temperature; wherein, the target test curves characterize the changes in voltage with charge state during the test process.

[0056] The charging / discharging equipment is an electronic measuring instrument used to perform charge / discharge tests on batteries. The test curve can be a charging test curve or a discharging test curve. Both the test curve and the target test curve have SOC (State of Charge) as the independent variable and the battery voltage as the dependent variable. SOC represents the percentage of remaining usable battery capacity. The target test curve can be a target charging test curve or a target discharging test curve. The temperature can be -20℃, -10℃, 0℃, 15℃, 25℃, 35℃, or 45℃, typically between -30℃ and 50℃.

[0057] Specifically, the computer equipment acquires test curves obtained by performing multiple charge-discharge tests on the target battery cell at different temperatures using a charge-discharge device. These test curves can be either discharge test curves or charging test curves. Based on these test curves, the capacity of the battery cell is determined. For each temperature, the computer equipment determines the target test curve corresponding to that temperature from multiple test curves based on the capacity of the test curves corresponding to that temperature. The charge-discharge device performs multiple charge-discharge tests on the battery cell at each temperature.

[0058] For example, a charging / discharging device performs five charging tests on a target battery cell at 25°C, obtaining a charging test curve C11 and a discharging test curve C12 for each test. A computer acquires these five charging and discharging test curves at 25°C and determines the capacity of each curve. Based on the capacities corresponding to the charging test curves, the computer determines the target charging curve at 25°C from the five charging test curves. Similarly, based on the capacities corresponding to the discharging test curves, the computer determines the target discharging curve at 25°C from the five discharging test curves. Figure 3 As shown in the figure, this is the target discharge curve at 25℃. In the figure, the vertical axis is voltage and the horizontal axis is state of charge (SOC).

[0059] Step S204: For each temperature, identify the slope of the target test curve corresponding to the corresponding temperature to obtain the slope data of the target test curve at the corresponding temperature.

[0060] The curve slope identification is used to determine the slope data of the curve. Each point on the target test curve represents the voltage value at a certain state of charge (SOC). This curve slope data can characterize the changes between adjacent points on the curve, and thus, characterize the changes of the entire target test curve.

[0061] Specifically, for each temperature, the computer device identifies the slope of the target test curve corresponding to the corresponding temperature, and obtains the slope data of the target test curve at each point at the corresponding temperature.

[0062] For example, at 25°C, the computer equipment identifies the slope of the target charging curve, obtaining the slope data corresponding to each point on the target charging curve. Similarly, the computer equipment identifies the slope of the target discharging curve, obtaining the slope data corresponding to each point on the target discharging curve.

[0063] Step S206: For each temperature, based on the slope data of the curve corresponding to the target test curve at the corresponding temperature, determine the charge state interval corresponding to the target test curve at the corresponding temperature, wherein the charge state interval characterizes the adjustment value of the charge state during the pulse test.

[0064] The charge state interval represents the difference between two charge states.

[0065] Specifically, for each temperature, the computer device, based on the curve slope data corresponding to the target test curve at that temperature, designates the charge state corresponding to a large change in curvature slope data as the first charge state, and the charge state corresponding to a gradual change in curvature slope data as the second charge state. The computer device determines the charge state interval of the first charge state as the first interval, and the charge state interval of the second charge state as the second interval. The first interval is smaller than the second interval. Specifically, the first interval for large changes in curvature slope data can be between 1.5% and 3%, and the second interval for gradual changes in curvature slope data can be between 5% and 10%.

[0066] It should be noted that large changes in curvature slope data indicate a large change in voltage for every unit change in charge state; conversely, gentle changes in curve slope data indicate a small change in charge for every unit change in charge state. Large changes in curvature slope data can be represented as a rapid rise or fall on a curve, while gentle changes in curve slope data can be represented as a flat curve.

[0067] Step S208: For each temperature, determine multiple pulse currents corresponding to the corresponding temperature, and based on the charge state interval and pulse current corresponding to the target test curve at the corresponding temperature, determine the pulse time at the corresponding temperature. The pulse time is used to instruct the charging and discharging device to perform pulse testing.

[0068] Specifically, for each temperature, the computer device determines the current range corresponding to that temperature and selects multiple pulse currents from that range. Based on the charge state interval and pulse current corresponding to the target test curve at that temperature, the pulse time at that temperature is determined. The computer device sends the pulse time and pulse current corresponding to each pulse current at that temperature to the charging / discharging device. The charging / discharging device performs pulse testing based on the pulse time and pulse current to obtain the voltage change curves corresponding to each temperature. During the pulse testing, the settling time T ≥ 5 min after each pulse, for example, 8 min ≤ T ≤ 180 min. Specifically, at 25°C, the charge state interval is 2% for charge states below 20%, 5% for charge states between 20% and 80%, and 2% for charge states above 80% and below 100%.

[0069] It should be noted that each temperature corresponds to a current range, and any two current ranges may overlap, intersect, or not overlap. For example, the current range is the same at normal temperatures of 25°C and 15°C, such as from 1C to 3C. However, the current range is different at sub-zero temperatures compared to normal temperatures. Considering that excessively high temperatures at sub-zero temperatures can damage the battery, the current range at sub-zero temperatures generally will not reach 3C (for a battery capacity of 40Ah, the pulse current is 120Ah).

[0070] Step S210: Obtain the voltage change curves corresponding to various temperatures obtained by the charging and discharging equipment performing pulse tests on the target battery based on the pulse time. These voltage change curves characterize the voltage changes with pulse current and time.

[0071] Specifically, for each temperature, the charging and discharging equipment performs pulse tests at the corresponding temperature according to the pulse duration of the target test curve, obtaining the voltage change curves corresponding to each temperature. The computer equipment acquires the voltage change curves corresponding to each temperature sent by the charging and discharging equipment. For example... Figure 4 As shown, the voltage (i.e., voltage in the figure) change curve is 4c. Among them, 4a is the pulse pattern of the pulse current (i.e. current in the figure) in the pulse test, and 4b is the change of the state of charge (SOC) over time when the pulse test is performed according to the pulses at various times (i.e. Time in the figure) in 4a.

[0072] Step S212: Based on the voltage change curves corresponding to each temperature, the parameters of the battery model corresponding to the target battery are obtained by fitting the parameters through a pre-constructed equivalent circuit model.

[0073] The equivalent circuit model in this application is a second-order equivalent circuit model. This equivalent circuit model consists of a power supply Voc, an internal resistance R0 (ohms), and two RC units connected in series. Each RC unit consists of a polarizing resistor and a polarizing capacitor connected in parallel, as detailed below. Figure 5 As shown. This parameter includes ohmic resistance, polarization resistance, time constant, and polarization capacitance.

[0074] Specifically, the computer device fits the voltage change curves corresponding to temperature to pre-built equivalent circuit models, obtaining parameters corresponding to temperature, pulse current, and charge state. For example, given temperature t, pulse current I1, and charge state X1, the values ​​of the ohmic resistance, polarization resistance, time constant, and polarization capacitance are obtained. This parameter fitting can be performed using data processing software such as Matlab, GT-Sute, and Amesim, employing at least one of the following methods: least squares method, Bayesian identification algorithm, and Kalman filtering algorithm.

[0075] The formula for the equivalent circuit model is as follows:

[0076]

[0077] C1=τ1 / R1

[0078] C2=τ2 / R2

[0079] Where U is the battery terminal voltage, U oc Let R0 be the open-circuit voltage, R1 and R2 be the ohmic resistors, τ1 and τ2 be the time constants, C1 and C2 be the polarization capacitors, and I be the pulse current. The RC circuit order N ≥ 1, preferably 2 ≤ N ≤ 5. Too few RC circuit orders result in inaccurate models, while too many RC circuit orders lead to excessive computational complexity, hindering parameter identification and simulation.

[0080] In the aforementioned method for obtaining battery model parameters, test curves are obtained by performing multiple tests on the target battery at different temperatures using a charging and discharging device. This allows for the determination of target test curves with high fidelity and accuracy for each temperature from these multiple tests. These target test curves characterize the voltage changes with charge state during the test. For each temperature, the slope of the target test curve corresponding to that temperature is identified, yielding slope data for that temperature. This clearly reflects whether the curve changes smoothly during charging and discharging. For each temperature, based on the slope data of the target test curve at that temperature, the charge state interval corresponding to that temperature is determined. This charge state interval characterizes the adjustment value of the charge state during pulse testing. Thus, based on the curve changes characterized by the target test curve, the adjustment value of the charge state matching the curve changes can be quickly and effectively determined, significantly saving time in subsequent parameter determination processes. For each temperature, multiple pulse currents corresponding to that temperature are determined. Based on the charge state interval and pulse current corresponding to the target test curve at that temperature, the pulse time at that temperature is determined. This pulse time is used to instruct the charging and discharging device to perform pulse testing. This method allows for real-time reflection of the pulse duration used for pulse testing. It acquires voltage change curves corresponding to various temperatures obtained from pulse testing of the target battery using a charge-discharge device based on this pulse duration. These voltage change curves characterize how the voltage changes with pulse current and time. Based on these voltage change curves corresponding to various temperatures, parameters are fitted using a pre-constructed equivalent circuit model to obtain the parameters of the battery model corresponding to the target battery. This approach achieves high accuracy in obtaining battery model parameters while saving time, significantly increasing the accuracy of the battery model parameters.

[0081] In one embodiment, such as Figure 6 As shown, based on the test curves obtained by performing multiple tests on the target battery at different temperatures using a charge-discharge device, the target test curves corresponding to each temperature are determined, including:

[0082] Step S602: For each temperature, with the current test count being the first test count, obtain a first number of first test curves at the corresponding temperature; wherein the first number is determined by the first test count.

[0083] The number of tests refers to the number of times the charging and discharging equipment performs charging and discharging tests on the target battery cell. For each temperature, one number of tests corresponds to a charging test curve and a discharging test curve.

[0084] Specifically, for each temperature, with the current test count being the first test count, the computer device acquires a first number of first test curves at the corresponding temperature. For example, at 25°C, assuming the first test count is 3 and the current test count is the 3rd, the computer device acquires 6 first test curves at 25°C.

[0085] It should be noted that the first test curve can be a charging test curve for the charging process or a discharging test curve for the discharging process. That is, at a certain temperature, for each test, two more first test curves are added, namely a charging test curve for the charging process and a discharging test curve for the discharging process. In other words, under the condition that the temperature does not change, the first number is twice the number of the first tests.

[0086] Step S604: For each temperature, determine the first capacity corresponding to each first test curve at the corresponding temperature, and based on the first capacity corresponding to each first test curve at the corresponding temperature, determine whether there is a target capacity among the multiple first capacities.

[0087] The first test curve can be either the first charging test curve during the charging process or the first discharging test curve during the discharging process. The first capacity can be either the first discharging capacity during the discharging process or the first charging capacity during the charging process. The target capacity can be either the target discharging capacity during the discharging process or the target charging capacity during the charging process.

[0088] Specifically, for each temperature, the computer device determines the first capacity corresponding to each first test curve at the corresponding temperature, and for the first charging capacity based on the first charging test curve characterizing the discharge process at the corresponding temperature, it determines whether there is a target charging capacity among the multiple first charging capacities, and based on the first discharging capacity based on the first discharging test curve characterizing the charging process, it determines whether there is a target discharging capacity among the multiple first discharging capacities.

[0089] Step S606: For each temperature, if the target capacity is not found among the multiple first capacities, continue to collect data until the current test number is the second test number.

[0090] The second test can generally be performed at least twice, preferably four times, to avoid unstable results due to too few tests. At the same time, it also avoids wasting testing time and resources by performing too many tests.

[0091] Specifically, for each temperature, if the target charging capacity is not found among the multiple first charging capacities but the target discharging capacity is found among the multiple first discharging capacities, data collection continues until the current test count is the second test count, in order to determine the target charging capacity. Alternatively, for each temperature, if the target charging capacity is found among the multiple first charging capacities but not among the multiple first discharging capacities, data collection continues until the current test count is the second test count, in order to determine the target discharging capacity. Or, for each temperature, if the target charging capacity is not found among the multiple first charging capacities but not among the multiple first discharging capacities, data collection continues until the current test count is the second test count, in order to determine the target charging capacity and the target discharging capacity.

[0092] Step S608: For each temperature, obtain a second number of second test curves at the corresponding temperature; wherein the second number is determined by the number of second tests.

[0093] It should be noted that the number of tests in the first test is less than the number of tests in the second test. The second test curve can be a second charging test curve during the charging process or a second discharging test curve during the discharging process.

[0094] Step S610: For each temperature, determine the second capacity corresponding to each second test curve at the corresponding temperature, and determine the average value of the second capacity based on multiple second capacities.

[0095] The second test curve can be either a second charging test curve during the charging process or a second discharging test curve during the discharging process. The second capacity can be either a second discharging capacity during the discharging process or a second charging capacity during the charging process. The average value of the second capacity can be either the average value of the second discharging capacity during the discharging process or the average value of the second charging capacity during the charging process.

[0096] Specifically, for each temperature, during the discharge process and under the corresponding temperature conditions, the second discharge capacity corresponding to each second discharge test curve is determined. The computer equipment performs an average calculation on the second discharge capacity to determine the average value of the second discharge capacity. For each temperature, during the charging process and under the corresponding temperature conditions, the second charging capacity corresponding to each second charging test curve is determined. The computer equipment performs an average calculation on the second charging capacity to determine the average value of the second charging capacity.

[0097] Step S612: For each temperature, compare each second capacity at the corresponding temperature with the average value of the second capacity to obtain the comparison result of the second capacity corresponding to each second capacity at the corresponding temperature.

[0098] Specifically, for each temperature, during the discharge process and at the corresponding temperature, the computer device compares each second discharge capacity with the average value of the second discharge capacity to obtain a comparison result of the second discharge capacity corresponding to each second discharge capacity during the discharge process and at the corresponding temperature. Similarly, for each temperature, during the charging process and at the corresponding temperature, the computer device compares each second charging capacity with the average value of the second charging capacity to obtain a comparison result of the second charging capacity corresponding to each second charging capacity during the charging process and at the corresponding temperature.

[0099] Step S614: For each temperature, based on the comparison results of the second capacity corresponding to each second capacity at the corresponding temperature, determine the target capacity from multiple second capacities, and take the second test curve corresponding to the target capacity as the target test curve at the corresponding temperature.

[0100] The target test curve can be either the target charging test curve during the charging process or the target discharging test curve during the discharging process.

[0101] Specifically, during the discharge process at the corresponding temperature, the computer equipment, based on the comparison results of the second discharge capacities corresponding to each second discharge capacity, determines the discharge difference between each second discharge capacity and the average value of the second discharge capacities, and takes the second discharge capacity corresponding to the smallest discharge difference as the target discharge capacity. The computer equipment uses the second discharge test curve corresponding to the target discharge capacity as the target discharge test curve at the corresponding temperature. During the charging process at the corresponding temperature, the computer equipment, based on the comparison results of the second charging capacities corresponding to each second charging capacity, determines the second charging difference between each second charging capacity and the average value of the second charging capacities, and takes the second charging capacity corresponding to the smallest second charging difference as the target charging capacity. The computer equipment uses the second charging test curve corresponding to the target charging capacity as the target charging test curve at the corresponding temperature.

[0102] In this embodiment, for each temperature, when the current test count is the first test count, the first capacity of the first test curve is pre-judged. This allows for a rapid and effective determination of whether the target capacity exists within the first capacity. By performing a coarse screening on each first test curve, additional testing can be avoided if the target capacity exists within the first capacity, saving testing time. For each temperature, if the target capacity does not exist among multiple first capacities, when the current test count is the second test count, the second capacity of the second test curve is re-judged. Combining the average value of the second capacity, the second capacity with the smallest difference from the average value of the second capacity is directly used as the target capacity, ensuring the effectiveness and accuracy of the target test curve.

[0103] In one embodiment, determining whether a target capacity exists among multiple first capacities based on the first capacities corresponding to each first test curve at the corresponding temperature includes: determining a maximum capacity, a minimum capacity, and a first capacity average value based on the first capacities corresponding to each first test curve at the corresponding temperature; comparing the difference between the maximum and minimum capacity values ​​with the first capacity average value to obtain a difference comparison result; if the difference comparison result is less than a difference threshold, determining that a target capacity exists among the multiple first capacities; if the difference comparison result is greater than or equal to the difference threshold, determining that no target capacity exists among the multiple first capacities.

[0104] The first test curve can be either the first charging test curve during the charging process or the first discharging test curve during the discharging process. The first capacity can be either the first discharging capacity during the discharging process or the first charging capacity during the charging process. The target capacity can be either the target discharging capacity during the discharging process or the target charging capacity during the charging process.

[0105] Specifically, for each temperature, during the charging process and at the corresponding temperature, the computer device determines the maximum charging capacity, the minimum charging capacity, and the average charging capacity based on the first charging capacity corresponding to each first charging test curve. The computer device subtracts the minimum charging capacity from the maximum charging capacity to obtain a first charging difference, and subtracts the average charging capacity from the first charging difference to obtain a charging difference comparison result. If the charging difference comparison result is less than the charging difference threshold, it is determined that a target charging capacity exists among the multiple first charging capacities; if the charging difference comparison result is greater than or equal to the charging difference threshold, it is determined that no target charging capacity exists among the multiple first charging capacities.

[0106] For each temperature, during the discharge process and at the corresponding temperature, the computer equipment determines the maximum discharge capacity, minimum discharge capacity, and average first discharge capacity based on the first discharge capacity corresponding to each first discharge test curve. The computer equipment subtracts the minimum discharge capacity from the maximum discharge capacity to obtain the first discharge difference, and subtracts the average first discharge capacity from the first discharge difference to obtain the discharge difference comparison result. If the discharge difference comparison result is less than the discharge difference threshold, it is determined that the target discharge capacity exists among the multiple first discharge capacities; if the discharge difference comparison result is greater than or equal to the discharge difference threshold, it is determined that the target discharge capacity does not exist among the multiple first discharge capacities.

[0107] For example, during discharge at 25°C, the first test is performed three times, resulting in three first discharge capacity curves. The computer equipment uses these three first discharge capacities—the maximum, minimum, and average discharge capacities—and subtracts the minimum from the maximum to obtain the first discharge difference. The computer equipment then subtracts the average discharge capacity from the first discharge difference to obtain the capacity range of the three tests. If this capacity range is less than 1%, a target discharge capacity is determined, and the test is stopped.

[0108] In this embodiment, the maximum capacity, minimum capacity, and average capacity are determined based on the first capacity corresponding to each first test curve at the corresponding temperature. Based on these values, a preliminary assessment of the first capacity of the first test curves is performed. This allows for a rapid and effective determination of whether the target capacity exists within the first capacity. By performing a coarse screening of each first test curve, additional testing can be avoided if the target capacity is present in the first capacity, thus saving testing time.

[0109] In one embodiment, the method further includes: for each temperature, if a target capacity exists among multiple first capacities, determining an average first capacity at the corresponding temperature based on the first capacity corresponding to each first test curve at the corresponding temperature; for each temperature, comparing each first capacity at the corresponding temperature with the average first capacity at the corresponding temperature to obtain a comparison result of the first capacity corresponding to each first capacity at the corresponding temperature; for each temperature, determining a target capacity from among the multiple first capacities based on the comparison result of the first capacity corresponding to each first capacity at the corresponding temperature, and using the first test curve corresponding to the target capacity as the target test curve at the corresponding temperature.

[0110] Specifically, for each temperature, during the discharge process and at the corresponding temperature, when a target discharge capacity exists within the first discharge capacity, the computer device calculates the average value of multiple first discharge capacities to obtain the average first discharge capacity. The computer device compares each average first discharge capacity with each individual first discharge capacity to obtain a comparison result corresponding to each first discharge capacity. Based on the comparison results, the computer device determines the first discharge difference between each first discharge capacity and the average first discharge capacity, and takes the first discharge capacity with the smallest first discharge difference as the target discharge capacity. The computer device uses the first discharge test curve corresponding to the target discharge capacity as the target discharge test curve at the corresponding temperature.

[0111] For each temperature, during the charging process, and assuming a target charging capacity exists within the first charging capacity at that temperature, the computer device calculates the average value of multiple first charging capacities to obtain the average first charging capacity. The computer device compares each average first charging capacity with each individual first charging capacity to obtain a comparison result corresponding to each first charging capacity. Based on the comparison results, the computer device determines the first charging difference between each first charging capacity and its average first charging capacity, and takes the first charging capacity with the smallest first charging difference as the target charging capacity. The computer device uses the first charging test curve corresponding to the target charging capacity as the target charging test curve at the corresponding temperature.

[0112] In this embodiment, if a target capacity is determined to exist within the first capacity, the average value of the first capacity is directly determined based on the first capacity. Combining the average value of the first capacity, the first capacity with the smallest difference from the average value is directly used as the target capacity. This achieves effective and accurate determination of the target test curve without requiring multiple additional tests. In other words, it saves testing time while ensuring accuracy, thus significantly improving the efficiency of the target test curve.

[0113] In one embodiment, such as Figure 7 As shown, for each temperature, the slope of the target test curve corresponding to that temperature is identified to obtain the slope data of the target test curve at that temperature, including:

[0114] Step S702: For each temperature, the first derivative curve corresponding to the target test curve at the corresponding temperature is determined by taking the first derivative of the target test curve at the corresponding temperature.

[0115] Specifically, for each temperature, the computer equipment uses MATLAB, ORIGIN, or EXCE1 software to perform first-order differentiation on the target test curve corresponding to that temperature, determining the first-order derivative curve at that temperature. For example, ... Figure 8 As shown in the figure, the effect is observed at 25℃. Figure 3 The first derivative curve is obtained by taking the first derivative of the target test curve shown.

[0116] Step S704: Based on the first derivative curve corresponding to the target test curve at the corresponding temperature, determine the slope data of the curve corresponding to the target test curve at the corresponding temperature.

[0117] Among them, the curve slope data are the slope values ​​corresponding to each state interval in the first-order conductor curve.

[0118] For each temperature, based on the slope data of the curve corresponding to the target test curve at that temperature, the charge state interval corresponding to the target test curve at that temperature is determined, including:

[0119] Step S706: For each temperature, compare the slope data of the curve corresponding to the target test curve at the corresponding temperature with the slope threshold to obtain multiple slope comparison results corresponding to the target test curve at the corresponding temperature.

[0120] Specifically, for each temperature, the computer device compares the slope data of the curve corresponding to the target test curve at the corresponding temperature with the slope threshold to obtain the slope comparison result corresponding to the target test curve at the corresponding temperature.

[0121] Step S708: For the comparison results of multiple slopes corresponding to the target test curve at the corresponding temperature, determine the charge state interval corresponding to the target test curve at the corresponding temperature.

[0122] Specifically, the computer device characterizes the slope comparison results as the charge state corresponding to a large change in curvature slope, as the first charge state, and characterizes the slope comparison results as the charge state corresponding to a gradual change in curvature slope data, as the second charge state. The computer device determines the charge state interval for the first charge state from a first interval range, and determines the charge state interval for the second charge state from a second interval range. For example, the first charge state can be a charge state below 20% or a charge state above 80%, and the second charge state is a charge state between 20% and 80%. It should be noted that the first interval range is smaller than the second interval range. For example, the first interval range is less than 5%, and the second interval range is greater than or equal to 5%.

[0123] In this embodiment, by taking the first derivative of the target test curve, the curve slope data can be quickly determined. Based on the curve slope data, the curve change of the target test curve can be accurately characterized. According to the curve change characterized by the target test curve, the charge state interval matching the curve change can be quickly and effectively determined, which greatly saves the time cost of subsequent parameter determination process.

[0124] In one embodiment, for each temperature, based on the multiple pulse currents corresponding to the corresponding temperature and the charge state interval corresponding to the corresponding temperature, the pulse time corresponding to each pulse current at the corresponding temperature is determined by the pulse time calculation formula.

[0125] The formula for calculating the pulse time t is as follows:

[0126]

[0127] Where C is the discharge rate and N is the charge state interval to be adjusted. For example, a charge state interval of 2% has a pulse rate of 3C (i.e., pulse current of 120Ah) and a pulse duration of 24s. A charge state interval of 5% has a pulse rate of 3C (i.e., pulse current of 120Ah) and a pulse duration of 60s.

[0128] In this embodiment, based on the charge state interval that accurately reflects the target test curve, a pulse time that matches the curve can be obtained. Thus, by using a charge state interval and pulse time that match the target test curve, a highly accurate and effective voltage change curve can be obtained.

[0129] To provide a clearer understanding of the technical solution of this application, a more detailed embodiment is provided and described below. Specifically:

[0130] Step 1: Determine the target test curve. The following description uses the discharge process as an example.

[0131] Specifically, for each temperature, with the current test count being the first test count, a first number of first test curves are acquired at the corresponding temperature. Based on the first capacity corresponding to each first test curve at the corresponding temperature, the maximum capacity, minimum capacity, and average first capacity are determined. The difference between the maximum and minimum capacity is compared with the average first capacity to obtain a difference comparison result. If the difference comparison result is less than a difference threshold, a target capacity is determined to exist among the multiple first capacities; if the difference comparison result is greater than or equal to the difference threshold, a target capacity is determined not to exist among the multiple first capacities. For each temperature, if no target capacity exists among the multiple first capacities, data acquisition continues until the current test count is the second test count. For each temperature, a second number of second test curves are acquired at the corresponding temperature. For each temperature, the second capacity corresponding to each second test curve at the corresponding temperature is determined, and based on the multiple second capacities, the average second capacity is determined. For each temperature, each second capacity at the corresponding temperature is compared with the average second capacity to obtain a comparison result of the second capacity corresponding to each second capacity at the corresponding temperature. For each temperature, based on the comparison results of the second capacity corresponding to each second capacity at that corresponding temperature, the target capacity is determined from multiple second capacities, and the second test curve corresponding to the target capacity is taken as the target test curve at the corresponding temperature.

[0132] For each temperature, if a target capacity exists among multiple first capacities, the average first capacity at that temperature is determined based on the first capacity corresponding to each first test curve at that temperature. For each temperature, each first capacity at that temperature is compared with the average first capacity at that temperature to obtain a comparison result of the first capacity corresponding to each first capacity at that temperature. For each temperature, based on the comparison result of the first capacity corresponding to each first capacity at that temperature, a target capacity is determined from among multiple first capacities, and the first test curve corresponding to the target capacity is taken as the target test curve at that temperature.

[0133] Step 2: Determine the charge state interval.

[0134] Specifically, for each temperature, the first derivative of the target test curve corresponding to that temperature is calculated using MATLAB or Origin software to determine the first derivative curve at that temperature. Based on this first derivative curve, the slope data of the curve corresponding to the target test curve at that temperature is determined. For each temperature, the slope data is compared with a slope threshold to obtain multiple slope comparison results. Based on these multiple slope comparison results, the charge state interval corresponding to the target test curve at that temperature is determined.

[0135] Step 3: Determine the pulse duration.

[0136] Specifically, for each temperature, multiple pulse currents corresponding to that temperature are determined. For each temperature, based on these pulse currents and the corresponding charge state interval, the pulse time corresponding to each pulse current at that temperature is determined using a pulse time calculation formula. The computer equipment sends the pulse times corresponding to each pulse current at each temperature, along with the individual pulse currents, to the charging / discharging equipment. The charging / discharging equipment performs pulse tests based on the pulse times and pulse currents to obtain voltage change curves corresponding to each temperature.

[0137] Step 4: Determine the parameters of the battery model based on the equivalent circuit model.

[0138] Specifically, a second-order equivalent circuit model is constructed based on the power supply, ohmic internal resistance, polarization resistance, and polarization capacitance. Then, based on the voltage change curves corresponding to various temperatures, parameters are fitted using the pre-constructed equivalent circuit model to obtain a parameter table containing the parameters of the battery model corresponding to the target battery. For example, this parameter table can be a three-dimensional table, with the independent variables being charge state, temperature, and pulse current.

[0139] Furthermore, to verify the accuracy of the parameters of the battery model in this application, the traditional HPPC method and the method of this application are compared. Figure 9 As shown, the discharge simulation data are obtained from traditional HPPC testing (10% interval) and the second-order equivalent circuit model established after the sampling interval in this embodiment. The scheme adopted in this embodiment can ensure the accuracy of the acquired parameters.

[0140] In this embodiment, multiple tests can determine the target test curves corresponding to each temperature with high fidelity and accuracy. By taking the first derivative of the target test curves, the smoothness of the curve changes during charging and discharging can be clearly reflected. Thus, based on the curve changes represented by the target test curves, the charge state interval matching the curve changes can be quickly and effectively determined, significantly saving time in subsequent parameter determination processes. Based on the highly adaptable charge state intervals, pulse testing can obtain highly accurate voltage change curves. In this way, while saving time, highly accurate battery model parameters can be obtained, greatly increasing the accuracy of the battery model parameters. Furthermore, compared to the traditional HPPC testing method, this embodiment requires approximately 4-6 hours to test pulse curve data at a single temperature and discharge rate. Testing at different discharge rates (e.g., testing four different discharge rates) at a certain temperature requires about one day. In contrast, the traditional HPPC method, if the test temperature is not 25°C, requires returning to 25°C for each charge state adjustment, and then adjusting back to the corresponding temperature for pulse discharge tests at different discharge rates (which can be tested simultaneously). Thus, the traditional HPPC method has a very long testing cycle for different SOCs at a certain temperature. This embodiment, however, adjusts the charge state while discharging pulses, eliminating the need to return to room temperature for adjustment, saving temperature adaptation time, and significantly shortening the test cycle and improving test accuracy.

[0141] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0142] Based on the same inventive concept, this application also provides a battery model parameter acquisition device for implementing the battery model parameter acquisition method described above. The solution provided by this device is similar to the implementation described in the above method; therefore, the specific limitations of one or more battery model parameter acquisition device embodiments provided below can be found in the limitations of the battery model parameter acquisition method described above, and will not be repeated here.

[0143] In one embodiment, such as Figure 10 As shown, a device for acquiring battery model parameters is provided, comprising: a first determining module 1002, an identification module 1004, a second determining module 1006, a third determining module 1008, an acquisition module 1010, and a fitting module 1012, wherein:

[0144] The first determining module 1002 is used to determine the target test curve corresponding to each temperature based on the test curve obtained by performing multiple tests on the target battery at different temperatures through a charging and discharging device; wherein, the target test curve characterizes the change of voltage with charge state during the test.

[0145] The identification module 1004 is used to identify the slope of the target test curve corresponding to each temperature, and obtain the slope data of the target test curve at the corresponding temperature.

[0146] The second determining module 1006 is used to determine, for each temperature, the charge state interval corresponding to the target test curve at the corresponding temperature based on the curve slope data corresponding to the target test curve at the corresponding temperature, wherein the charge state interval characterizes the adjustment value of the charge state during the pulse test.

[0147] The third determining module 1008 is used to determine multiple pulse currents corresponding to each temperature, and to determine the pulse time at the corresponding temperature based on the charge state interval and pulse current corresponding to the target test curve at the corresponding temperature. The pulse time is used to instruct the charging and discharging device to perform pulse testing.

[0148] The acquisition module 1010 is used to acquire the voltage change curves corresponding to various temperatures obtained by the charging and discharging equipment performing pulse tests on the target battery based on the pulse time. The voltage change curves characterize the change of voltage with pulse current and time.

[0149] The fitting module 1012 is used to perform parameter fitting based on the voltage change curves corresponding to each temperature, using a pre-built equivalent circuit model, to obtain the parameters of the battery model corresponding to the target battery.

[0150] In one embodiment, the first determining module 1002 is configured to, for each temperature, acquire a first number of first test curves at the corresponding temperature, where the current test count is a first test count; wherein the first number is determined by the first test count. For each temperature, determine the first capacity corresponding to each first test curve at the corresponding temperature, and based on the first capacity corresponding to each first test curve at the corresponding temperature, determine whether a target capacity exists among the multiple first capacities. For each temperature, if no target capacity exists among the multiple first capacities, continue sampling until the current test count is a second test count. For each temperature, acquire a second number of second test curves at the corresponding temperature; wherein the second number is determined by the second test count. For each temperature, determine the second capacity corresponding to each second test curve at the corresponding temperature, and based on the multiple second capacities, determine the average value of the second capacity. For each temperature, compare each second capacity at the corresponding temperature with the average value of the second capacity to obtain a comparison result of the second capacity corresponding to each second capacity at the corresponding temperature. For each temperature, based on the comparison result of the second capacity corresponding to each second capacity at the corresponding temperature, determine the target capacity from the multiple second capacities, and use the second test curve corresponding to the target capacity as the target test curve at the corresponding temperature.

[0151] In one embodiment, the first determining module 1002 is configured to determine a maximum capacity, a minimum capacity, and a first average capacity based on the first capacity corresponding to each first test curve at the corresponding temperature. The difference between the maximum and minimum capacity is compared with the first average capacity to obtain a difference comparison result. If the difference comparison result is less than a difference threshold, it is determined that a target capacity exists among the multiple first capacities; if the difference comparison result is greater than or equal to the difference threshold, it is determined that no target capacity exists among the multiple first capacities.

[0152] In one embodiment, the first determining module 1002 is configured to, for each temperature, if a target capacity exists among multiple first capacities, determine the average value of the first capacity at the corresponding temperature based on the first capacity corresponding to each first test curve at the corresponding temperature. For each temperature, each first capacity at the corresponding temperature is compared with the average value of the first capacity at the corresponding temperature to obtain a comparison result of the first capacity corresponding to each first capacity at the corresponding temperature. For each temperature, based on the comparison result of the first capacity corresponding to each first capacity at the corresponding temperature, a target capacity is determined from the multiple first capacities, and the first test curve corresponding to the target capacity is used as the target test curve at the corresponding temperature.

[0153] In one embodiment, the identification module 1004 is configured to, for each temperature, determine the first derivative curve corresponding to the target test curve at that temperature by taking the first derivative of the target test curve at that temperature. Based on the first derivative curve corresponding to the target test curve at that temperature, the slope data of the curve corresponding to the target test curve at that temperature is determined. For each temperature, the slope data of the curve corresponding to the target test curve at that temperature is compared with a slope threshold to obtain multiple slope comparison results corresponding to the target test curve at that temperature. For the multiple slope comparison results corresponding to the target test curve at that temperature, the charge state interval corresponding to the target test curve at that temperature is determined.

[0154] In one embodiment, the third determining module 1008 is used to determine, for each temperature, the pulse time corresponding to each pulse current at the corresponding temperature based on the multiple pulse currents corresponding to the corresponding temperature and the charge state interval corresponding to the corresponding temperature, by means of a pulse time calculation formula.

[0155] Each module in the aforementioned battery model parameter acquisition device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the operations corresponding to each module.

[0156] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 11 As shown, this computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The database stores data for acquiring battery model parameters. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communicating with external terminals via a network connection. When executed by the processor, the computer program implements a method for acquiring battery model parameters.

[0157] Those skilled in the art will understand that Figure 11The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0158] In one embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0159] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the steps in the above method embodiments.

[0160] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0161] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0162] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0163] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method of acquiring parameters of a battery model, characterized by, The method comprises: determining a target test curve corresponding to each temperature based on test curves obtained by testing the target battery at different temperatures by the charging and discharging device, wherein the target test curve represents the change of voltage with the state of charge during the test; for each temperature, identifying the curve slope of the target test curve corresponding to the respective temperature to obtain the curve slope data corresponding to the target test curve at the respective temperature; for each temperature, based on the curve slope data corresponding to the target test curve at the respective temperature, taking the state of charge corresponding to the large change of the curve slope data as the first state of charge, and taking the state of charge corresponding to the gentle change of the curve slope data as the second state of charge; determining the state of charge interval of the first state of charge as the first interval, and determining the state of charge interval of the second state of charge as the second interval, wherein the state of charge interval represents the adjustment value of the state of charge during the pulse test; for each temperature, determining a plurality of pulse currents corresponding to the respective temperature, and based on the plurality of pulse currents corresponding to the respective temperature and the state of charge interval corresponding to the respective temperature, determining the pulse time corresponding to each pulse current at the respective temperature by a pulse time calculation formula, wherein the pulse time is used to instruct the charging and discharging device to perform the pulse test; obtaining the voltage change curve corresponding to each temperature obtained by the charging and discharging device based on the pulse time for the pulse test on the target battery, wherein the voltage change curve represents the change of voltage with the pulse current and time; based on the voltage change curve corresponding to each temperature, performing parameter fitting by using the pre-constructed equivalent circuit model to obtain the parameters of the battery model corresponding to the target battery.

2. The method of claim 1, wherein, The method comprises: for each temperature, when the current test number is a first test number, obtaining a first number of first test curves at the respective temperature, wherein the first number is determined by the first test number; for each temperature, determining the first capacity corresponding to each first test curve at the respective temperature, and based on the first capacity corresponding to each first test curve at the respective temperature, determining whether a target capacity exists in the plurality of first capacities; for each temperature, when the target capacity does not exist in the plurality of first capacities, continuing to collect until the current test number is a second test number; for each temperature, obtaining a second number of second test curves at the respective temperature, wherein the second number is determined by the second test number; for each temperature, determining the second capacity corresponding to each second test curve at the respective temperature, and based on the plurality of second capacities, determining a second capacity average value; for each temperature, comparing each second capacity at the respective temperature with the second capacity average value to obtain a second capacity comparison result corresponding to each second capacity at the respective temperature. For each temperature, a target capacity is determined from the plurality of second capacities based on second capacity comparison results corresponding to each of the second capacities at the respective temperature, and a second test curve corresponding to the target capacity is taken as a target test curve at the respective temperature.

3. The method of claim 2, wherein, The determining whether the target capacity exists in the plurality of first capacities based on the first capacity corresponding to each of the first test curves at the respective temperature comprises: determining a maximum capacity value, a minimum capacity value, and a first capacity average value based on the first capacity corresponding to each of the first test curves at the respective temperature; comparing a difference between the maximum capacity value and the minimum capacity value with the first capacity average value to obtain a difference comparison result; in a case where the difference comparison result is less than a difference threshold, determining that the target capacity exists in the plurality of first capacities, and in a case where the difference comparison result is greater than or equal to the difference threshold, determining that the target capacity does not exist in the plurality of first capacities.

4. The method of claim 2, wherein, The method further comprises: For each temperature, in a case where the target capacity exists in the plurality of first capacities, determining a first capacity average value at the respective temperature based on the first capacity corresponding to each of the first test curves at the respective temperature; For each temperature, comparing each of the first capacities at the respective temperature with the first capacity average value at the respective temperature to obtain a first capacity comparison result corresponding to each of the first capacities at the respective temperature; For each temperature, a target capacity is determined from the plurality of second capacities based on second capacity comparison results corresponding to each of the second capacities at the respective temperature, and a second test curve corresponding to the target capacity is taken as a target test curve at the respective temperature.

5. The method of claim 1, wherein, The identifying the curve slope data corresponding to the target test curve at the respective temperature based on the first derivative curve corresponding to the target test curve at the respective temperature comprises: For each temperature, a first derivative curve corresponding to the target test curve at the respective temperature is determined by performing first-order derivation on the target test curve corresponding to the respective temperature; The identifying the curve slope data corresponding to the target test curve at the respective temperature based on the first derivative curve corresponding to the target test curve at the respective temperature comprises: The method further comprises: For each temperature, comparing the curve slope data corresponding to the target test curve at the respective temperature with a slope threshold to obtain a plurality of slope comparison results corresponding to the target test curve at the respective temperature; For each temperature, a target capacity is determined from the plurality of second capacities based on second capacity comparison results corresponding to each of the second capacities at the respective temperature, and a second test curve corresponding to the target capacity is taken as a target test curve at the respective temperature.

6. An apparatus for acquiring parameters of a battery model, characterized by comprising: The apparatus comprises: a first determining module configured to determine a target test curve corresponding to each temperature based on test curves obtained by performing a plurality of tests on a target battery at different temperatures by a charging and discharging device, wherein the target test curve represents a change of voltage with a change of state of charge during the test; an identifying module configured to, for each temperature, identify a curve slope of a target test curve corresponding to the respective temperature to obtain curve slope data corresponding to the target test curve at the respective temperature; and an identifying module configured to, for each temperature, identify a curve slope of a target test curve corresponding to the respective temperature to obtain curve slope data corresponding to the target test curve at the respective temperature; and The second determining module is configured to, for each temperature, determine, based on the curve slope data corresponding to the target test curve at the corresponding temperature, a charge state corresponding to a large change in the curve slope data as a first charge state, and a charge state corresponding to a gentle change in the curve slope data as a second charge state; determine a charge state interval of the first charge state as a first interval, and determine a charge state interval of the second charge state as a second interval, wherein the charge state interval represents an adjustment value of the charge state in the pulse test process. The third determining module is configured to, for each temperature, determine a plurality of pulse currents corresponding to the corresponding temperature, and determine, based on the plurality of pulse currents corresponding to the corresponding temperature and the charge state interval corresponding to the corresponding temperature, a pulse time corresponding to each pulse current at the corresponding temperature by using a pulse time calculation formula, wherein the pulse time is used to instruct the charge and discharge equipment to perform the pulse test. The acquisition module is configured to acquire a voltage change curve corresponding to each temperature, which is obtained by performing the pulse test on the target battery by the charge and discharge equipment based on the pulse time, and represents a change of the voltage with the pulse current and the time. The fitting module is configured to perform parameter fitting on an equivalent circuit model pre-constructed based on the voltage change curve corresponding to each temperature, to obtain a parameter of a battery model corresponding to the target battery.

7. The apparatus of claim 6, wherein, The first determining module is configured to, for each temperature, acquire a first number of first test curves at the corresponding temperature when the current test number is a first test number, wherein the first number is determined by the first test number; for each temperature, determine a first capacity corresponding to each first test curve at the corresponding temperature, and determine whether a target capacity exists in a plurality of first capacities based on the first capacity corresponding to each first test curve at the corresponding temperature; for each temperature, continue to collect until the current test number is a second test number, when the target capacity does not exist in the plurality of first capacities; for each temperature, acquire a second number of second test curves at the corresponding temperature, wherein the second number is determined by the second test number; for each temperature, determine a second capacity corresponding to each second test curve at the corresponding temperature, and determine a second capacity average based on the plurality of second capacities; for each temperature, compare each second capacity at the corresponding temperature with the second capacity average to obtain a second capacity comparison result corresponding to each second capacity at the corresponding temperature; and for each temperature, determine the target capacity from the plurality of second capacities based on the second capacity comparison result corresponding to each second capacity at the corresponding temperature, and determine the second test curve corresponding to the target capacity as the target test curve at the corresponding temperature.

8. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that, The processor executes the computer program to implement the steps of the method in any one of claims 1 to 5.

9. A computer readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method in any one of claims 1 to 5.

10. A computer program product comprising a computer program, characterized in that, The computer program, which when executed by the processor, implements the steps of the method of any one of claims 1 to 5.

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