Battery direct current internal resistance and battery capacity data preprocessing method, system and program product

Abstract

The application discloses a battery direct-current internal resistance and battery capacity data preprocessing method, system and program product, wherein the battery direct-current internal resistance data preprocessing method comprises the following steps: determining the current state of the period between the current moment and the previous moment according to the current change value of the current moment and the previous moment; calculating the battery direct-current internal resistance of the current moment and the true value interval of the battery direct-current internal resistance corresponding to the current moment according to the current state of the period between the current moment and the previous moment and the charge-discharge state of the battery; determining whether the battery direct-current internal resistance is the true value according to the true value interval; and correcting the battery direct-current internal resistance if the battery direct-current internal resistance is not the true value. The application determines the authenticity of the battery data and corrects the false value, improves the data quality, and reduces the battery SOH prediction time and improves the prediction accuracy of the battery SOH to a certain extent.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power batteries, in particular to a battery direct current resistance and battery capacity data preprocessing method, system and program product. BACKGROUND

[0002] The battery SOH (State of Healthy) is a key parameter of the power battery, which is a measure of the available energy of the battery and an important reference for predicting the remaining life of the battery. Therefore, the estimation of SOH is very important. The SOH of the power battery cannot be directly measured and needs to be estimated according to the related parameters in the use process of the battery.

[0003] The current estimation method based on big data is the most commonly used battery SOH estimation method. The technical scheme of the power battery SOH estimation method based on big data is generally as follows: first, obtain the battery mass data and process the data; then extract the features of the data and divide the data into training set and validation set; finally, build a data-based starting model, input the training set data into the model for operation, output the predicted value, compare the output layer result with the validation set, adjust the model parameters according to the comparison difference, and then continuously train the model and iterate the model parameters to achieve the final expected prediction result.

[0004] However, in the estimation method based on big data, the authenticity of the battery data is not considered during preprocessing. Without detailed preprocessing, the battery data imported into the data-driven model will increase the prediction time and affect the robustness of the model, and will also increase the estimation error and reduce the estimation accuracy. SUMMARY

[0005] The purpose of the present application is to provide a battery direct current resistance and battery capacity data preprocessing method, system and program product, which aims to solve the problem that the estimation method based on big data in the prior art does not consider the authenticity of the battery data during preprocessing.

[0006] To solve the above technical problems, the present application is realized by the following technical scheme:

[0007] On the one hand, the present application provides a battery direct current resistance data preprocessing method, comprising:

[0008] determining the current state of the period between the current time and the previous time according to the current change value of the current between the current time and the previous time;

[0009] calculating the battery direct current resistance at the current time and the true value interval of the battery direct current resistance corresponding to the current time according to the current state of the period between the current time and the previous time and the charge and discharge state of the battery;

[0010] determining whether the battery DC internal resistance is a true value according to the true value interval;

[0011] If the battery DC internal resistance is not a true value, the battery DC internal resistance is corrected.

[0012] Further, the current state of the period between the current time and the previous time is determined according to the current change value, comprising:

[0013] determining the current state of the period according to whether the current change value is greater than a preset change value;

[0014] If yes, the period is a variable current period;

[0015] If no, the period is a constant current period;

[0016] Wherein, the current value of the current time is I t , the current value of the previous time is I t-1 , and the current change value is |I t -I t-1 |.

[0017] Further, the battery DC internal resistance of the current time and the true value interval of the battery DC internal resistance corresponding to the current time are calculated according to the current state of the period between the current time and the previous time and the charge and discharge state of the battery, comprising:

[0018] When the period is a constant current period, the battery DC internal resistance R CC = ΔU / I;

[0019] In the charging state, ΔU = U t -U t-1 , R CC = (U t -U t-1 ) / I, and the maximum DC internal resistance is

[0020] In the discharging state, ΔU = U t-1 -U t , R CC = (U t-1 -U t ) / I, and the maximum DC internal resistance is

[0021] When the period is a variable current period, the battery DC internal resistance R RC = ΔU / ΔI;

[0022] In the charging state, ΔU = U t -U t-1, ΔI = |I t - t-1 |, R RC = (U t -U t-1 ) / |I t - t-1 |, the maximum value of DC internal resistance R max = (U max -U t-1 ) / |I t - t-1 |;

[0023] In the discharge state, ΔU = U t-1 -U t , ΔI = |I t -I t-1 |, R RC = (U t-1 -U t ) / |I t - t-1 |, the maximum value of DC internal resistance R max = (U t-1 -U min ) / |I t - t-1 |;

[0024] The true value interval of the DC internal resistance of the battery is [0, R max ];

[0025] Wherein, ΔU is the voltage change, U t is the voltage value at the current time, U t-1 is the voltage value at the previous time, I is the geometric mean current of the constant current period, that is ΔI is the current change, U max is the upper limit value of the battery voltage when U t is the maximum value, U min is the lower limit value of the battery voltage when U t is the maximum value, U max and U min are related to the material of the battery.

[0026] Further, if the DC internal resistance of the battery is not the true value, the DC internal resistance of the battery is corrected, comprising:

[0027] According to the SOC-OCV curve, the corresponding open circuit voltage OCV SOC，t at the current time is obtained;

[0028] According to U t = OCV SOC，t -I t R tObtaining the internal resistance value R of the current time t = (OCV SOC，t - U t ) / I t ;

[0029] Taking the battery DC internal resistance true value R t-1 of the previous time as a prior value, and taking the internal resistance value R t of the current time as an observation value, the battery DC corrected internal resistance BR t of the current time is calculated according to the Kalman filtering method.

[0030] On the other hand, the application also provides a battery capacity data preprocessing method, comprising:

[0031] calculating the capacity difference value of the battery capacity at the first time and the battery capacity at the second time after a preset time, and the theoretical maximum change value of the battery capacity between the first time and the second time;

[0032] judging whether the battery capacity at the second time is a true value according to the capacity difference value and the theoretical maximum change value of the battery capacity;

[0033] if the battery capacity at the second time is not a true value, then correcting the battery capacity at the second time.

[0034] Further, the calculation of the capacity difference value of the battery capacity at the first time and the battery capacity at the second time after a preset time, and the theoretical maximum change value of the battery capacity between the first time and the second time, comprises:

[0035] the battery capacity value at the first time is C t , the battery capacity value at the second time is C t+Δt , and the capacity difference value between the second time and the first time is (C t+Δt - C t );

[0036] the theoretical maximum change value of the battery capacity between the first time and the second time is ΔC max = I max * Δt;

[0037] wherein, the first time is t, the preset time is Δt, the second time is t+Δt, and I max is the maximum current value in the preset time.

[0038] Further, if the battery capacity at the second time is not a true value, then correcting the battery capacity at the second time, comprises:

[0039] obtaining the battery SOC at the first time and the second time t obtaining the battery SOC at the first time and the second time t+Δt ;

[0040] obtaining the battery SOC at the first time and the second time t obtaining the battery SOC at the first time and the second time t+Δt obtaining the battery SOC change (SOC t+Δt -SOC t ) at the first time and the second time;

[0041] obtaining the battery capacity change (AC = (SOC t+Δt -SOC t )*C N ) in the preset time according to the battery SOC change;

[0042] obtaining the battery capacity correction value C t+Δt =C t +AC at the second time according to the battery capacity change;

[0043] wherein C N is the rated capacity of the battery.

[0044] The application further provides a battery DC internal resistance data preprocessing system, comprising:

[0045] a first judging unit, configured to judge the current state of the period between the current time and the previous time according to the current change value of the current at the current time and the previous time;

[0046] a first calculating unit, configured to calculate the battery DC internal resistance at the current time and the true value interval of the battery DC internal resistance corresponding to the current time according to the current state of the period between the current time and the previous time and the charge-discharge state of the battery;

[0047] a second judging unit, configured to judge whether the battery DC internal resistance is true according to the true value interval;

[0048] a first correcting unit, configured to correct the battery DC internal resistance if the battery DC internal resistance is not true.

[0049] The application further provides a battery capacity data preprocessing system, comprising:

[0050] a second calculating unit, configured to calculate the capacity difference value of the battery capacity at the first time and the battery capacity at the second time after a preset time, and the theoretical maximum change value of the battery capacity between the first time and the second time;

[0051] a third judging unit, configured to judge whether the battery capacity at the second time is true according to the capacity difference value and the theoretical maximum change value of the battery capacity;

[0052] A second correction unit is configured to correct the battery capacity at the second time if the battery capacity at the second time is not a true value.

[0053] The application further provides a computer program product comprising a computer program which, when executed by a processor, implements the steps of the battery DC internal resistance data preprocessing method or the battery capacity data preprocessing method.

[0054] The application provides a battery DC internal resistance data preprocessing method, a battery capacity data preprocessing method, a system and a computer program product, wherein the battery DC internal resistance data preprocessing method comprises the following steps: determining the current state of the period between the current time and the previous time according to the current change value of the current between the current time and the previous time; calculating the battery DC internal resistance at the current time and the true value interval of the battery DC internal resistance corresponding to the current time according to the current state of the period between the current time and the previous time and the charge-discharge state of the battery; determining whether the battery DC internal resistance is a true value according to the true value interval; and correcting the battery DC internal resistance if the battery DC internal resistance is not a true value. The application determines the true and false of the battery data and corrects the false value, thereby improving the data quality, reducing the battery SOH prediction time and improving the prediction accuracy of the battery SOH to a certain extent. BRIEF DESCRIPTION OF DRAWINGS

[0055] In order to more clearly illustrate the technical solutions of the embodiments of the application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0056] Figure 1 The flowchart of the battery DC internal resistance data preprocessing method provided by the application is shown in the figure.

[0057] Figure 2 The flowchart of the battery capacity data preprocessing method provided by the application is shown in the figure.

[0058] Figure 3 The sub-flowchart of the battery DC internal resistance data preprocessing method provided by the application is shown in the figure.

[0059] Figure 4 The sub-flowchart of the battery DC internal resistance data preprocessing method provided by the application is shown in the figure.

[0060] Figure 5 The sub-flowchart of the battery DC internal resistance data preprocessing method provided by the application is shown in the figure.

[0061] Figure 6A sub-process schematic diagram of the battery direct current resistance data preprocessing method provided by the embodiment of the present application is shown in the figure;

[0062] Figure 7 A sub-process schematic diagram of the battery capacity data preprocessing method provided by the embodiment of the present application is shown in the figure;

[0063] Figure 8 A sub-process schematic diagram of the battery capacity data preprocessing method provided by the embodiment of the present application is shown in the figure;

[0064] Figure 9 A sub-process schematic diagram of the battery capacity data preprocessing method provided by the embodiment of the present application is shown in the figure;

[0065] Figure 10 A structure block diagram of the battery direct current resistance data preprocessing system provided by the embodiment of the present application is shown in the figure;

[0066] Figure 11 A structure block diagram of the battery capacity data preprocessing system provided by the embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0067] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0068] It should be understood that, when used in the specification and the appended claims, the terms “comprise” and “include” indicate the presence of described features, integers, steps, operations, elements, and / or components, but do not exclude one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0069] It should also be understood that the terms used in the present application specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the present application specification and the appended claims, unless otherwise clearly indicated by the context, the singular forms “a”, “an” and “the” are intended to include the plural forms.

[0070] It should be further understood that the term “and / or” used in the present application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0071] Combination Figure 1 As shown in the figure, in one aspect, the present application provides a battery direct current resistance data preprocessing method, comprising steps S10-S40:

[0072] S10, determining the current state of the period between the current time and the previous time according to the current change value of the current between the current time and the previous time;

[0073] S20, calculating the battery DC internal resistance of the current time and the true value interval of the battery DC internal resistance corresponding to the current time according to the current state of the period between the current time and the previous time and the charge-discharge state of the battery;

[0074] S30, determining whether the battery DC internal resistance is true according to the true value interval;

[0075] S40, if the battery DC internal resistance is not true, correcting the battery DC internal resistance.

[0076] In the embodiment of the application, when the battery SOH estimation method is performed, the working data of the battery is divided into multiple periods, the beginning and the end of each period are the current time and the previous time respectively, and when the battery DC internal resistance data of the current time is refined and pretreated, firstly, it is determined whether the current state of the period is in a constant current state or a variable current state according to the current change value of the current between the current time and the previous time, and whether the state of the battery is in a charging state or a discharging state according to the battery DC of the current time. Different current states and battery states will result in different calculation formulas of the battery DC internal resistance, and the battery DC internal resistance of the current time is calculated according to Ohm's law; secondly, the true value interval of the battery DC internal resistance corresponding to the current time is calculated according to the current state and the state of the battery, so as to determine whether the battery DC internal resistance is true; finally, when the battery DC internal resistance is not true, i.e. the battery DC internal resistance is a false value, the battery DC internal resistance is corrected. By judging the true and false of the battery DC internal resistance and correcting the false value, the quality of the battery DC internal resistance data is improved, and the battery SOH prediction time is reduced and the prediction accuracy of the battery SOH is improved to a certain extent.

[0077] Specifically, it is determined whether the state of the battery is in a charging state or a discharging state according to whether the current of the current time is less than zero; if yes, the battery is in a charging state; if no, the battery is in a discharging state. That is, I t <0, the battery is in a charging state, I t >0, the battery is in a discharging state.

[0078] In combination with Figure 3 As shown in FIG. 10, in some embodiments, the current state of the period between the current time and the previous time is determined according to the current change value of the current between the current time and the previous time, i.e. step S10 includes steps S101-S103:

[0079] S101, determining the current state of the period according to whether the current change value is greater than a preset change value;

[0080] S102, if yes, the time period is a variable current time period;

[0081] S103, if no, the time period is a constant current time period;

[0082] wherein the current value at the current time is I t , the current value at the previous time is I t-1 , and the current change value is |I t -I t-1 |.

[0083] In the embodiment, the current value I t at the current time and the current value I t-1 at the previous time are obtained, and the current change value is |I t -I t-1 |.

[0084] In some embodiments, the current change value is 1A, |I t -I t-1 |>1A, the time period is a variable current time period, and |I t -I t-1 |≤1A, the time period is a constant current time period. Figure 4 It can be understood that the preset change value can be set according to the accuracy of the battery SOH estimation. The current state of the time period is determined by the current change value, so that the value of the battery direct current resistance is more accurate, and the false judgment of the calculated battery direct current resistance is prevented, thereby improving the accuracy of the battery SOH estimation.

[0085] In some embodiments, the battery direct current resistance at the current time and the true value interval of the battery direct current resistance corresponding to the current time are calculated according to the current state of the time period between the current time and the previous time and the charge and discharge state of the battery, that is, step S20 includes steps S201-S203:

[0086] S201, when the time period is a constant current time period, the battery direct current resistance R CC =ΔU / I. In the charging state, ΔU=U t -U t-1 , R CC =(U t -U t-1 ) / I, and the maximum direct current resistance is

[0087] In the discharging state, ΔU=U t-1 -U t , R CC =(U t-1 -U t ) / I, and the maximum direct current resistance is

[0088] S202, When the time period is the converter period, the battery DC internal resistance R RC =ΔU / ΔI;

[0089] In the charging state, ΔU = U t -U t-1 ΔI=|I t -I t-1 |,R RC =(U t -U t-1 ) / |I t -I t-1 | Maximum DC internal resistance R max =(U max -U t-1 ) / |I t -I t-1 |;

[0090] In the discharge state, ΔU=U t-1 -U t ΔI=|I t -I t-1 |,R RC =(U t-1 -U t ) / |I t -I t-1 | Maximum DC internal resistance R max =(U t-1 -U min ) / |I t -I t-1 |;

[0091] S203, The true range of the battery's DC internal resistance is [0, R]. max ];

[0092] Where ΔU is the voltage change, U t U is the voltage value at the current moment. t-1 I represents the voltage value at the previous moment, and I represents the geometric mean current during the constant current period, i.e. ΔI is the change in current, U max U when charging t Maximum battery voltage upper limit, U min U during discharge t The lower limit of the maximum battery voltage, U max and U min It is related to the materials used in the battery.

[0093] In this embodiment, during the constant current period, the current I remains almost unchanged, and the geometric mean of the current is taken. During the charging state, the voltage gradually increases, and ΔU = Ut -U t-1 , R CC =(U t -U t-1 ) / I, in the discharge state, the voltage gradually decreases, ΔU=U t-1 -U t , R CC =(U t-1 -U t ) / I; in the current changing period, the current gradually changes, R RC =ΔU / ΔI. By the change of the current and the different states of the battery, the battery DC internal resistance is accurately calculated according to different formulas, which improves the accuracy of the battery SOH estimation. max and U min are related to the materials of the battery, and the commonly used battery materials in the prior art include ternary lithium battery, lithium manganate battery and lithium iron phosphate battery, wherein U max and U min of the ternary lithium battery are 4.3V and 2.8V respectively, U max and U min of the lithium manganate battery are 4.2V and 2.7V respectively, and U max and U min of the lithium iron phosphate battery are 3.65V and 2.5V respectively. According to different lithium batteries, the upper limit value and the lower limit value of the battery voltage are obtained, so as to calculate the maximum DC internal resistance R max in the corresponding state, the true value interval of the battery DC internal resistance is obtained more accurately, and then whether the battery DC internal resistance is the true value is accurately judged.

[0094] As shown in Figure 5 , in some embodiments, whether the battery DC internal resistance is the true value is judged according to the true value interval, that is, step S30 includes steps S301-S303:

[0095] S301, whether the battery DC internal resistance is the true value is judged according to whether the battery DC internal resistance is in its corresponding true value interval;

[0096] S302, if yes, the battery DC internal resistance is the true value;

[0097] S303, if no, the battery DC internal resistance is the false value.

[0098] In this embodiment, the battery DC internal resistance is the true value when it is in its corresponding true value interval, otherwise it is the false value. The true value interval judgment method can accurately and quickly judge the true and false of the battery DC internal resistance.

[0099] As shown in Figure 6As shown, in some embodiments, if the battery's DC internal resistance is not a true value, then the battery's DC internal resistance is corrected, i.e., step S40 includes steps S401 to S403:

[0100] S401. Obtain the corresponding open-circuit voltage OCV at the current moment based on the SOC-OCV curve. SOC，t ;

[0101] S402, according to U t =OCV SOC，t -I t R t Get the current internal resistance value R t =(OCV) SOC，t -U t ) / I t ;

[0102] S403, change the true value R of the battery DC internal resistance at the previous moment. t-1 As a priori value, the current internal resistance value R t As an observation, the current DC-corrected internal resistance BR of the battery is calculated using the Kalman filter method. t .

[0103] In this embodiment, during battery use, the state of charge (SOC) is the ratio of the actual amount of electricity provided in the current state to the amount of electricity provided in a fully charged state. Open circuit voltage (OCV) refers to the voltage measured when the battery is unloaded. The open circuit voltage changes with SOC; therefore, the corresponding open circuit voltage OCV at the current moment can be obtained from the SOC-OCV curve. SOC，t According to the actual voltage U t And according to U t =OCV SOC，t -I t R t The internal resistance R of the battery can be calculated. t Kalman filtering is a recursive algorithm for estimating the state of a dynamic system. Prior values ​​refer to the state predictions obtained based on the system's dynamic model and the current state estimate before estimating the current state. Observations refer to the actual measurement data acquired at the current moment, reflecting the true state of the system. The Kalman filtering method is used to calculate the current DC-corrected internal resistance BR of the battery. t The fast response and small error improve the accuracy of battery SOH estimation.

[0104] Combination Figure 2 As shown, on the other hand, the present invention also provides a battery capacity data preprocessing method, including steps S50 to S70:

[0105] S50, calculate a capacity difference value of the battery capacity at the first time and the battery capacity at the second time after the preset time, and a theoretical maximum change value of the battery capacity between the first time and the second time;

[0106] S60, judge whether the battery capacity at the second time is a true value according to the capacity difference value and the theoretical maximum change value of the battery capacity;

[0107] S70, if the battery capacity at the second time is not the true value, correct the battery capacity at the second time.

[0108] In the embodiment of the application, when the second time battery capacity data is preprocessed, that is, when the second time battery capacity is judged to be true or false, the capacity difference value between the second time and the first time before the predetermined time is needed to be judged. If the capacity difference value does not exceed the maximum change value of the capacity, the second time battery capacity data is a true value, otherwise, it is a false value, and the second time battery capacity needs to be corrected. By judging the true or false of the battery capacity and correcting the false value, the quality of the battery capacity data is improved, not only the battery SOH prediction time is reduced, the robustness of the battery SOH estimation model is avoided, but also the prediction accuracy of the battery SOH is improved, and the estimation error of the battery SOH is reduced.

[0109] In combination with Figure 7 In some embodiments, the capacity difference value of the battery capacity at the first time and the battery capacity at the second time after the preset time is calculated, and the theoretical maximum change value of the battery capacity between the first time and the second time, that is, step S50 includes steps S501-S502:

[0110] S501, the battery capacity value at the first time is C t , the battery capacity value at the second time is C t+Δt , and the capacity difference value between the second time and the first time is (C t+Δt -C t ) ;

[0111] S502, the theoretical maximum change value of the battery capacity between the first time and the second time is ΔC max =I max *Δt;

[0112] Wherein, the first time is t, the preset time is Δt, the second time is t+Δt, and I max is the maximum current value in the preset time.

[0113] In this embodiment, the preset time Δt is set according to the battery's operating environment. When determining the authenticity of the battery capacity at the second moment, it is necessary to judge based on the capacity difference between the second moment and the first moment before the preset time Δt. In practical application scenarios, the battery capacity value C at the first moment... t This is a true value to ensure the battery capacity value C at the second time step. t+Δt The accuracy of authenticity verification. Battery capacity is usually expressed in ampere-hours (Ah) or milliampere-hours (mAh), reflecting the amount of charge the battery can store and release. The maximum capacity change ΔC within a preset time Δt is also considered. max =I max *Δt.

[0114] Combination Figure 8 As shown, in some embodiments, the battery capacity at the second moment is determined to be a true value based on the capacity difference and the theoretical maximum change value of the battery capacity. That is, step S60 includes steps S601 to S603:

[0115] S601. Determine whether the battery capacity is the true value based on whether the capacity difference is less than the maximum capacity change value;

[0116] S602, If yes, then the battery capacity is the true value;

[0117] S603. If not, the battery capacity is a false value.

[0118] In this embodiment, if the capacity difference is less than the maximum capacity change, that is, the battery capacity value does not exceed the theoretical change, the battery capacity value at the second moment is the true value. If the capacity difference is greater than the maximum capacity change, the battery capacity value at the second moment is the false value. By judging the true or false value of the battery capacity value at the second moment, the false value can be avoided from affecting the accuracy of the battery SOH estimation, thus improving the accuracy of the battery SOH estimation.

[0119] Combination Figure 9 As shown, in some embodiments, if the battery capacity value at the second time moment is not a true value, the battery capacity value at the second time moment is corrected, that is, step S70 includes steps S701 to S704:

[0120] S701, Obtain the battery SOC at the first and second moments. t With battery SOC t+Δt ;

[0121] S702, based on battery SOC t With battery SOC t+Δt Obtain the change in battery SOC (SOC) t+Δt -SOC t );

[0122] S703, obtaining a battery capacity variation ΔC=(SOC t+Δt -SOC t )*C N ;

[0123] S704, obtaining a battery capacity correction value C t+Δt =C t +ΔC at the second moment according to the battery capacity variation.

[0124] Wherein, C N is the rated capacity of the battery.

[0125] In the embodiment, the battery SOC variation (SOC t+Δt -SOC t ) is the proportional change value of the battery power storage amount, C N is the rated capacity of the battery, (SOC t+Δt -SOC t )*C N is the battery capacity variation ΔC, and ΔC is actually the battery capacity variation from the first moment to the second moment, so the corrected battery capacity correction value C t+Δt =C t +ΔC at the second moment, by correcting the pseudo value, the quality of the battery capacity data is improved, not only the battery SOH prediction time is reduced, the robustness of the battery SOH estimation model is avoided, and the prediction accuracy of the battery SOH is improved, and the estimation error of the battery SOH is reduced.

[0126] In combination with Figure 10 , the application further provides a battery DC internal resistance data preprocessing system, comprising:

[0127] A first judgment unit 100 is used for judging the current state of the period between the current moment and the previous moment according to the current value and the previous value of the current at the current moment and the previous moment.

[0128] A first calculation unit 200 is used for calculating the battery DC internal resistance at the current moment and the true value interval of the battery DC internal resistance corresponding to the current moment according to the current state of the period between the current moment and the previous moment and the charge-discharge state of the battery.

[0129] A second judgment unit 300 is used for judging whether the battery DC internal resistance is true according to the true value interval.

[0130] A first correction unit 400 is used for correcting the battery DC internal resistance if the battery DC internal resistance is not true.

[0131] In the embodiment of the present application, the quality of the battery DC internal resistance data is improved by judging the authenticity of the battery DC internal resistance and correcting the false value, and the battery SOH prediction time is reduced and the battery SOH prediction accuracy is improved to a certain extent.

[0132] In combination Figure 11 As shown in the figure, the present application further provides a battery capacity data preprocessing system, comprising:

[0133] The second calculation unit 500 is configured to calculate a capacity difference value between the battery capacity at the first time and the battery capacity at the second time after the preset time, and a theoretical maximum change value of the battery capacity between the first time and the second time.

[0134] The third judgment unit 600 is configured to judge whether the battery capacity at the second time is a true value according to the capacity difference value and the theoretical maximum change value of the battery capacity.

[0135] The second correction unit 700 is configured to correct the battery capacity at the second time if the battery capacity at the second time is not a true value.

[0136] In the embodiment of the present application, the quality of the battery capacity data is improved by judging the authenticity of the battery capacity and correcting the false value, the battery SOH prediction time is reduced, the robustness of the battery SOH estimation model is avoided to be affected, the battery SOH prediction accuracy is improved, and the battery SOH estimation error is reduced.

[0137] The present application further provides a computer program product comprising a computer program, which, when executed by a processor, implements the steps of the above-mentioned battery DC internal resistance data preprocessing method or battery capacity data preprocessing method.

[0138] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can easily think of various equivalent modifications or replacements within the technical range disclosed by the present application, and these modifications or replacements should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A battery direct current internal resistance data preprocessing method, characterized in that, The method comprises the following steps: determining the current state of the period between the current time and the previous time according to the current change value of the current between the current time and the previous time; determining the current state of the period according to whether the current change value is greater than a preset change value; If yes, the time period is a variable current time period; if no, the time period is a constant current time period; wherein the current value at the current time is I t , the current value at the previous time is I t-1 , and the current change value is |I t -I t-1 |; calculating the battery DC resistance at the current time and the true value interval of the battery DC resistance corresponding to the current time according to the current state of the period between the current time and the previous time and the charge-discharge state of the battery; The battery direct current resistance R CC = ΔU / I; in the charging state, ΔU = U t -U t-1 , R CC = (U t -U t-1 ) / I, the maximum direct current resistance In the discharging state, ΔU = U t-1 -U t , R CC = (U t-1 -U t ) / I, the maximum direct current resistance When the period is a variable current period, the battery direct current resistance R RC = ΔU / ΔI; in the charging state, ΔU = U t -U t-1 , ΔI = |I t -I t-1 |, R RC = (U t -U t-1 ) / |I t -I t-1 |, the maximum direct current resistance R max = (U max -U t-1 ) / |I t -I t-1 |; in the discharging state, ΔU = U t-1 -U t , ΔI = |I t -I t-1 |, R RC = (U t-1 -U t ) / |I t -I t-1 |, the maximum direct current resistance R max = (U t-1 -U min ) / |I t -I t-1 |; the true value interval of the battery direct current resistance is [0, R max ]; wherein ΔU is a voltage change, U t is a voltage value at the current moment, U t-1 is a voltage value at the previous moment, I is a geometric mean current of the constant current period, that is ΔI is a current change, U max is an upper limit value of the battery voltage of the maximum value U t in the charging state, U min is an upper limit value of the battery voltage of the maximum value U t a lower limit value of the maximum battery voltage, U max and U min related to the materials of the battery; determining whether the battery DC resistance is a true value according to the true value interval; if the battery DC resistance is not a true value, correcting the battery DC resistance. According to the SOC-OCV curve, the open circuit voltage OCV corresponding to the current time is obtained SOC，t ; according to the U t = OCV SOC，t - I t R t The internal resistance value R of the current time is obtained t = (OCV SOC，t - U t ) / I t ; the battery DC internal resistance true value R t-1 of the previous time is taken as the prior value, the internal resistance value R t of the current time is taken as the observation value, and the battery DC corrected internal resistance BR t of the current time is calculated according to the Kalman filtering method.

2. A battery DC internal resistance data preprocessing system, characterized in that, The method comprises the following steps: a first determining unit is configured to determine the current state of the period between the current time and the previous time according to the current change value of the current between the current time and the previous time; determining the current state of the period according to whether the current change value is greater than a preset change value; If yes, the time period is a variable current time period; if no, the time period is a constant current time period; wherein the current value at the current time is I t , the current value at the previous time is I t-1 , and the current change value is |I t -I t-1 |; The first calculation unit is configured to calculate a battery direct current resistance at a current moment and a true value interval of the battery direct current resistance corresponding to the current moment according to a current state of a period between the current moment and a previous moment and a charge-discharge state of the battery; when the period is a constant current period, the battery direct current resistance R CC = ΔU / I; in a charging state, ΔU = U t -U t-1 , R CC = (U t -U t-1 ) / I, the maximum direct current resistance In a discharging state, ΔU = U t-1 -U t , R CC = (U t-1 -U t ) / I, the maximum direct current resistance When the period is a variable current period, the battery direct current resistance R RC = ΔU / ΔI; in a charging state, ΔU = U t -U t-1 , ΔI = |I t -I t-1 |, R RC = (U t -U t-1 ) / |I t -I t-1 |, the maximum direct current resistance R max = (U max -U t-1 ) / |I t -I t-1 |; in a discharging state, ΔU = U t-1 -U t , ΔI = |I t -I t-1 |, R RC = (U t-1 -U t ) / |I t -I t-1 |, the maximum direct current resistance R max = (U t-1 -U min ) / |I t -I t-1 |; the true value interval of the battery direct current resistance is [0, R max ]; wherein ΔU is a voltage variation, U t is a voltage value at the current moment, U t-1 is a voltage value at the previous moment, I is a geometric mean current of the constant current period, namely ΔI is a current variation, U max Umaxis the maximum value of the battery voltage t Umaxis the maximum value of the battery voltage min Uminis the minimum value of the battery voltage t Uminis the minimum value of the battery voltage max Umaxand Umin min related to the material of the battery a second determining unit is configured to determine whether the battery DC resistance is a true value according to the true value interval; The first correction unit is used to correct the battery's DC internal resistance if it is not a true value; and to obtain the corresponding open-circuit voltage OCV at the current moment based on the SOC-OCV curve. SOC，t According to U t =OCV SOC，t -I t R t Get the current internal resistance value R t =(OCV) SOC，t -U t ) / I t The true value of the battery's DC internal resistance R at the previous moment. t-1 As a priori value, the current internal resistance value R t As an observation, the current DC-corrected internal resistance BR of the battery is calculated using the Kalman filter method. t .

3. A computer program product comprising a computer program, characterized in that, the computer program is executed by the processor to realize the steps of the battery DC resistance data preprocessing method in claim 1.

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