State of Charge Estimation Method, Computer Device, and Computer Storage Medium

Abstract

The present application discloses a method, device, and storage medium for estimating the state of charge based on a data model to improve the accuracy of SOC estimation. The method part includes: using the current voltage, real-time current, real-time temperature, and charge-discharge cycle count of the battery to estimate the true remaining capacity of the battery at present in the battery data model; using the next correction target voltage, real-time current, real-time temperature, and charge-discharge cycle count to estimate the true remaining capacity corresponding to the correction target voltage; calculating the calculated remaining capacity of the battery based on ampere-hour integration, and determining the calculated full discharge capacity at present according to the previous charging result; calculating the self-discharge rate of the battery based on the calculated remaining capacity, the true remaining capacity corresponding to the current voltage, and the true remaining capacity of the next correction target voltage; using the self-discharge rate to correct the calculated remaining capacity to obtain the corrected calculated remaining capacity; and determining the current state of charge of the battery by calculating the full discharge capacity and the corrected calculated remaining capacity.

Description

Technical Field

[0001] This application relates to the field of computer technology, and in particular, to a method for estimating the state of charge, a computer device, and a computer storage medium. Background Art

[0002] The state of charge (SOC) of a battery (full English name: State of Charge, abbreviation: SOC) is a parameter that reflects the remaining capacity of the battery. Without accurate SOC, overcharging and over-discharging may occur frequently during normal use, which may lead to a shortened battery life. For users, without accurate SOC, it may also be impossible to accurately estimate the battery performance and usage time. Therefore, the accuracy evaluation of SOC is of great significance.

[0003] Currently, the current remaining capacity is often directly calculated by ampere-hour integration, and the SOC is calculated by combining the current full-discharge capacity calculated from the previous charge. However, the accurate estimation of SOC involves non-linear effects such as open-circuit voltage, instantaneous current, charge and discharge rate, ambient temperature, and battery temperature. These external characteristics are affected by different materials, different processes, etc., and interact with each other. The SOC simply calculated by the above method is prone to deviation and fluctuation. Therefore, there is an urgent need for an accurate SOC estimation method. Summary of the Invention

[0004] This application provides a method for estimating the state of charge based on a data model, a computer device, and a computer storage medium to solve the technical problem that the SOC is prone to deviation.

[0005] In a first aspect, a method for estimating the state of charge based on a data model for the discharge state of a battery is provided, including:

[0006] Using the current voltage, real-time current, real-time temperature, and charge and discharge cycle times of the battery, estimate the current true remaining capacity RMC0 of the battery in the battery data model;

[0007] Using the next correction target voltage, real-time current, real-time temperature, and charge and discharge cycle times of the battery, estimate the true remaining capacity RMC1 corresponding to the next correction target voltage;

[0008] Based on ampere-hour integration, calculate the current calculated remaining capacity RMC of the battery, and determine the current calculated full-discharge capacity FDC according to the previous charge result;

[0009] According to the calculated remaining capacity RMC, the true remaining capacity RMC0 corresponding to the current voltage, and the true remaining capacity RMC1 of the next correction target voltage, calculate the self-discharge rate K1 of the next discharge stage of the battery;

[0010] Using the self-discharge rate K1, correct the calculated remaining capacity RMC to obtain the corrected calculated remaining capacity RMC 、 ;

[0011] Based on the calculated full discharge capacity FDC and the corrected calculated remaining capacity RMC 、 , determine the current state of charge of the battery.

[0012] Furthermore, estimating the current state of charge of the battery based on the calculated full discharge capacity FDC and the corrected calculated remaining capacity RMC 、 includes:

[0013] When using the current voltage, current real-time current, real-time temperature, and number of charge and discharge cycles to determine the current true full discharge capacity FDC0 of the battery in the battery data model;

[0014] Based on the calculated full discharge capacity FDC and the true full discharge capacity FDC0, correct the currently calculated full discharge capacity FDC of the battery to obtain the corrected calculated full discharge capacity FDC 、 ;

[0015] Based on the corrected calculated full discharge capacity FDC 、 and the corrected calculated remaining capacity RMC 、 , estimate the current state of charge of the battery.

[0016] Furthermore, calculate the self-discharge rate K1 of the battery in the next stage by the following method:

[0017] K1 = (RMC – RMC1) * A / (RMC0 – RMC1);

[0018] Furthermore, the corrected calculated remaining capacity RMC 、 is obtained by the following method:

[0019] RMC 、 = K1 * RMC / A;

[0020] Furthermore, the step of correcting the currently calculated full discharge capacity FDC of the battery based on the calculated full discharge capacity FDC and the true full discharge capacity FDC0 to obtain the corrected calculated full discharge capacity FDC 、 includes:

[0021] Calculate the capacity difference between the calculated full discharge capacity FDC and the true full discharge capacity FDC0;

[0022] Determine the full discharge correction value RMCn per unit time according to the capacity difference;

[0023] When the calculated full discharge capacity FDC is greater than the true full discharge capacity FDC0, the calculated full discharge capacity FDC decreases by the full discharge correction value RMCn per unit time to obtain the corrected calculated full discharge capacity FDC 、 ;

[0024] When the calculated full discharge capacity FDC is less than the true full discharge capacity FDC0, the calculated full discharge capacity FDC increases by the full discharge correction value RMCn per unit time to obtain the corrected calculated full discharge capacity FDC 、 。

[0025] Further, the data model is obtained in advance in the following manner:

[0026] The charge and discharge data of the battery are recorded in real time. The charge and discharge data include the charge and discharge sequence times, the temperature corresponding to each cycle, the charge and discharge voltage, the charge and discharge current data, and the remaining capacity and full discharge capacity of the battery corresponding to the recorded charge and discharge data;

[0027] Based on the charge and discharge data of the battery and the remaining capacity and full discharge capacity of the battery corresponding to the charge and discharge data, the data model is established.

[0028] In a second aspect, a method for estimating the state of charge based on a data model is provided for the charging state of a battery, including:

[0029] Using the current voltage, real-time current, real-time temperature and charge and discharge cycle times of the battery, estimate the current true remaining capacity RMC0 of the battery in the battery data model;

[0030] Using the next correction target voltage, real-time current, real-time temperature and charge and discharge cycle times of the battery, estimate the true remaining capacity RMC1 corresponding to the next correction target voltage;

[0031] Based on ampere-hour integration, calculate the current calculated remaining capacity RMC of the battery, and determine the current calculated full charge capacity FCC according to the previous discharge result;

[0032] According to the calculated remaining capacity RMC, the true remaining capacity RMC0 corresponding to the current voltage and the true remaining capacity RMC1 of the next correction target voltage, calculate the self-charging rate K2 of the next charging stage of the battery;

[0033] Using the self-charging rate K2, correct the calculated remaining capacity RMC to obtain the corrected calculated remaining capacity RMC 、 ;

[0034] Through the calculated full charge capacity FCC and the corrected calculated remaining capacity RMC 、, determine the current state of charge of the battery.

[0035] Further, calculate the self - charging rate K2 of the battery in the next stage in the following manner:

[0036] K2 = (RMC1–RMC) * A / (RMC1–RMC0);

[0037] In a third aspect, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the state - of - charge estimation method according to any one of the first aspect or the second aspect are implemented.

[0038] In a fourth aspect, a computer - readable storage medium is provided. The computer - readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the state - of - charge estimation method according to any one of the first aspect or the second aspect are implemented.

[0039] In the above solution, based on the data - model method, after determining the self - discharge / charging rate, the self - discharge / charging rate is used to correct the calculated remaining RMC obtained by the ampere - hour algorithm during the discharge / charging process, so as to obtain a more accurate corrected calculated remaining capacity RMC 、 , and then through the full - discharge capacity FDC and the corrected calculated remaining capacity RMC 、 , estimate the current state of charge of the battery, effectively improving the accuracy of the final real - time state of charge SOC. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments of the present application. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0041] Figure 1 is a flowchart of the state - of - charge estimation method in Embodiment 1 of the present application;

[0042] Figure 2 is another flowchart of the state - of - charge estimation method in Embodiment 2 of the present application;

[0043] Figure 3 is a schematic block diagram of the state - of - charge estimation device provided in Embodiment 3 of the present application;

[0044] Figure 4 is a schematic diagram of the computer device in Embodiment 5 of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0046] In the present application, a method for estimating the state of charge based on a data model is proposed. This method for estimating the state of charge can be used to estimate the state of charge during the charging or discharging process of a battery. The core idea is to calculate the self-discharge rate and self-charging rate during the charging or discharging process of the battery in combination with the data model, so as to use the self-discharge rate to correct the remaining capacity participating in the SOC calculation during the discharging process, making the final SOC closer to the actual situation, and using the self-charging rate to correct the remaining capacity participating in the SOC calculation during the charging process, making the final SOC closer to the actual situation. The following will be divided into the discharging process and the charging process to describe in detail the method for estimating the state of charge based on the data model provided by the present application.

[0047] Embodiment 1

[0048] Please refer to Figure 1 As shown, a method for estimating the state of charge based on a data model is provided for the discharging state. The method includes the following steps:

[0049] S10: Obtain the current battery parameters of the battery. The current battery parameters include the current voltage, the current real-time current, the real-time temperature, and the number of charge-discharge cycles.

[0050] The above battery may refer to the batteries of various electrical devices in various application scenarios, which is not limited in the present application. When it is necessary to obtain the real-time SOC value of the battery for display or participate in the decision-making of other functional modules, it is necessary to accurately obtain the real-time SOC value of the battery. First, the current battery parameters of the battery need to be obtained.

[0051] Among them, the process of a battery being fully charged and discharged once completely is called a charge-discharge cycle. It can be understood that after multiple cycles, the battery life will decay, and the corresponding remaining capacity, full charge and full discharge capacity, etc. will be different. That is to say, the current number of charge-discharge cycles of the battery corresponds to different decay degrees. Therefore, in the present application, in order to accurately evaluate the actual SOC situation of the battery, the current battery parameters obtained also include the current number of charge-discharge cycles of the battery.

[0052] It should be noted that the current battery may be in a discharging state or a charging state. When the current battery is in a discharging state, the current voltage is the discharging voltage and the current real-time current is the discharging current; when the current battery is in a charging state, the current voltage is the charging voltage and the current real-time current is the charging current. This Embodiment 1 is the discharging process of the battery. Taking the discharging state as an example, for instance, in the current battery parameters, the number of charge-discharge cycles is the 100th cycle, the current battery temperature is 35 °C, the current discharging current is 10 A, and the discharging voltage is 4000 mV.

[0053] S20: Using the current voltage, real-time current, real-time temperature, and number of charge-discharge cycles of the battery, estimate the current true remaining capacity RMC0 of the battery in the data model.

[0054] S30: Using the next corrected target voltage, real-time current, real-time temperature, and number of charge-discharge cycles of the battery, estimate the true remaining capacity RMC1 corresponding to the next corrected target voltage.

[0055] After obtaining the current battery parameters of the above battery, the true remaining capacity RMC0 corresponding to the current voltage of the battery and the true remaining capacity RMC1 corresponding to the next corrected target voltage can be determined in the data model of the battery by using the current real-time current, real-time temperature, and number of charge-discharge cycles.

[0056] It should be noted that in this application, the data model of the battery is a data model obtained based on a large amount of test data of the battery. This data model is used to estimate the true remaining capacity of the battery by using the current battery parameters, that is, the true remaining capacity in this application is obtained based on the data model.

[0057] In one embodiment, the data model is obtained in advance through the following method: Record the charge-discharge data of the battery in real time. The charge-discharge data includes the number of charge-discharge sequences, the temperature corresponding to each cycle, charge-discharge voltage, charge-discharge current data, and record the remaining capacity and full discharge capacity of the battery corresponding to the charge-discharge data; establish the data model based on the charge-discharge data of the battery and the remaining capacity and full discharge capacity of the battery corresponding to the charge-discharge data.

[0058] That is to say, the data model is obtained by conducting tests on the battery based on the actual charge and discharge test data of the battery. Specifically, for example, during the test, if it is the 100th charge and discharge cycle, the battery temperature is 35°C, the discharge current is 10 A, the discharge voltage is 4000 mV, and the remaining capacity and full discharge capacity of the battery corresponding to this condition are recorded. Another example is that during the test, if it is the 200th charge and discharge cycle, the battery temperature is -10°C, the discharge current is 20 A, the discharge voltage is 3000 mV, and the corresponding true remaining capacity and true full discharge capacity are also recorded. Based on the same test, the test is continuously repeated to obtain a large amount of actual test record data. Finally, a data model is established with a large amount of actual test record data. In this way, the established data model establishes the corresponding relationship between the real-time temperature, voltage, current, charge and discharge cycle times and the true remaining capacity and true full discharge capacity.

[0059] In this way, through the pre-established data model, using the current voltage, current real-time current, real-time temperature, and charge and discharge cycle times, the current true remaining capacity RMC0 of the battery can be determined in the battery data model. Through the pre-established data model, using the next target correction voltage, current real-time current, real-time temperature, and charge and discharge cycle times, the true remaining capacity RMC1 of the battery corresponding to the next target correction voltage can be determined in the battery data model.

[0060] Specifically, the current voltage, current real-time current, real-time temperature, and charge and discharge cycle times are compared with the data in the data model to determine the corresponding true remaining capacity RMC0 under the current voltage, current real-time current, real-time temperature, and charge and discharge cycle times. The next target correction voltage, current real-time current, real-time temperature, and charge and discharge cycle times are compared with the data in the data model to determine the corresponding true remaining capacity RMC1 under the next target correction voltage, current real-time current, real-time temperature, and charge and discharge cycle times.

[0061] It should be noted that as described above, after establishing the data model, the remaining capacity of the battery corresponding to different voltages under different conditions can be known. For example, it is known that under a certain condition, the true remaining capacity at 3500 mV and the true remaining capacity at 3600 mV. Then, for the corresponding discharge process, the voltage will become lower and lower. When the current is 3600 mV, the next target correction voltage is 3500 mV. Therefore, through the data model, the true remaining capacity corresponding to the next target correction voltage can also be known.

[0062] For example, using the 100th cycle, real-time temperature of 35°C, current discharge current of 10 A, and current discharge voltage of 3500 mV, determine the true remaining capacity RMC0 corresponding to the current discharge voltage of 3500 mV. Using the 100th cycle, real-time temperature of 35°C, and current discharge current of 10 A, determine the true remaining capacity RMC1 corresponding to the next target correction of 3400 mV.

[0063] S40: Calculate the current calculated remaining capacity RMC of the battery based on ampere-hour integration, and determine the current calculated full discharge capacity FDC according to the previous charging result.

[0064] It should be noted that in this application, the calculated remaining capacity RMC will also be obtained based on ampere-hour integration. It is emphasized that the current calculated remaining capacity RMC is calculated using ampere-hour integration, and this calculated remaining capacity RMC = A*H (real-time current * time). Due to many factors such as current measurement accuracy and time calculation deviation, there will be a certain deviation between the current calculated remaining capacity RMC and the true remaining capacity RMC0. Therefore, subsequent calculations are needed to gradually bring the two closer and correct the deviation of the calculated remaining capacity RMC.

[0065] Among them, the calculated full discharge capacity FDC is calculated from the previous charge. In theory, the charged capacity and the discharged capacity are the same. Therefore, in this application, the total capacity charged in the previous charge is used as the theoretical value of the full discharge capacity for the next discharge, that is, the calculated full discharge capacity FDC is equal to the total charged capacity in the previous charging state.

[0066] S50: Calculate the self-discharge rate K1 of the next discharge stage of the battery according to the calculated remaining capacity RMC, the true remaining capacity RMC0 corresponding to the current voltage, and the true remaining capacity RMC1 of the next correction target voltage.

[0067] S60: Use the self-discharge rate K1 to correct the calculated remaining capacity RMC to obtain the corrected calculated remaining capacity RMC 、 。

[0068] In one embodiment, the self-discharge rate K1 of the next stage of the battery is calculated in the following manner:

[0069] K1 = (RMC – RMC1) * A / (RMC0 – RMC1);

[0070] As described above, K1 represents the self-discharge rate, RMC represents the calculated remaining capacity, RMC1 represents the true remaining capacity of the next correction target voltage, RMC0 represents the true remaining capacity corresponding to the current voltage, and A represents the amplification factor. Specifically, considering the unit problem and for ease of calculation, this A can be 1000.

[0071] To facilitate the understanding of the self-discharge rate K1, an example is given here to illustrate the self-discharge rate K1.

[0072] Suppose the current voltage is 3600 mV, the corresponding true remaining capacity RMC0 is 6000 mAH, and the true remaining capacity RMC1 corresponding to the next target corrected voltage of 3500 mV is 5000 mAH. Then, when the current discharge voltage changes from 3600 mV to 3500 mV, the true capacity discharged is the difference between RMC0 and RMC1, that is, 1000 mAH. Similarly, assume that the calculated remaining capacity RMC corresponding to 3600 mV is 5900 mAH, and the true remaining capacity RMC1 corresponding to the next target corrected voltage of 3500 mV is still 5000 mAH. Then, during the discharge process, the difference in the calculated remaining capacity discharged from 3600 mV to 3500 mV is 900 mAH.

[0073] Then, according to the above calculation method of the self-discharge rate K1, the self-discharge rate K1 value can be obtained as K1 = (5900 - 5000) / (6000 - 5000) = 0.9. It can be seen that this self-discharge rate K1 value reflects the deviation relationship between the calculated remaining capacity RMC calculated by actual ampere-hour integration and the final true remaining capacity RMC1.

[0074] Therefore, it is necessary to correct the calculated remaining capacity RMC using the self-discharge rate K1.

[0075] For the convenience of calculation, take the amplification factor A as 1000. It is necessary to amplify the self-discharge rate K1 by 1000, and the obtained K1 value = (5900 - 5000) * 1000 / (6000 - 5000) = 900. Use K1 to correct the calculated remaining capacity RMC, that is: RMC 、 = K1 * RMC / A; where RMC 、 represents the corrected calculated remaining capacity, K1 represents the self-discharge rate, RMC represents the calculated remaining capacity, and A represents the amplification factor.

[0076] S70: Estimate the current state of charge of the battery through the calculated full discharge capacity FDC and the corrected calculated remaining capacity RMC 、 , and estimate the current state of charge of the battery.

[0077] In this way, from SOC = RMC / FDC, it can be seen that after correcting RMC, the final current real-time SOC can be obtained through the calculated full discharge capacity FDC and the corrected calculated remaining capacity RMC 、 is obtained.

[0078] It should be noted that when the calculated remaining capacity RMC decreases, the final SOC will decrease accordingly. For example, if the true SOC = 5000 / 10000 = 50%, and assume SOC = (5000–10) / 10000 = 49.9000%, it can be seen that when the calculated remaining capacity RMC decreases by 10, the SOC changes by 0.1000%. Therefore, based on the data model method of the present application, after determining the self-discharge rate K1, the calculated remaining capacity RMC is corrected using the self-discharge rate K1, and a more accurate corrected calculated remaining capacity RMC can be obtained. 、 , and then through the calculated full discharge capacity FDC and the corrected calculated remaining capacity RMC 、 , estimate the current state of charge of the battery, effectively improving the accuracy of the final real-time state of charge SOC.

[0079] It should be noted that, for another example, assume the true SOC =5000 / 10000 = 50%, and the calculated SOC = 5000 / 11000 = 45.45%. It can be seen that even if the calculated remaining capacity RMC is corrected to approach the true value, when the calculated full discharge capacity FDC is different, there is still a deviation in the SOC.

[0080] It can be seen that if the calculated remaining capacity RMC and the calculated full discharge capacity FDC change simultaneously, it will cause the SOC to change slowly or quickly. For example, the calculated SOC = 5000 / 11000 = 45.4545%, and SOC = (5000–10) / 11000 =44.3636%. It can be seen that when the calculated remaining capacity RMC decreases by 10, the SOC changes by 0.0909%, that is, the difference between the calculated SOC and the true SOC becomes larger by 0.0091%. Assume that SOC = (5000–10) / (11000 -5) =45.3842%. It can be seen that when the calculated remaining capacity RMC decreases by 10 and the calculated full discharge capacity FDC decreases by 5, the SOC changes by 0.0703%, that is, the difference between the calculated SOC and the true SOC becomes larger by 0.0297%.

[0081] Therefore, while adding the correction to the calculated remaining capacity RMC, it is also necessary to add the correction to the calculated full discharge capacity FDC. Therefore, in one embodiment, further, in step S70, that is: through the calculated full discharge capacity FDC and the corrected calculated remaining capacity RMC 、 , estimate the current state of charge of the battery, which specifically includes the following steps:

[0082] S80: When using the current voltage, the current real-time current, the real-time temperature, and the charge and discharge cycle times, in the battery data model, determine the current true full discharge capacity FDC0 of the battery.

[0083] S90: Correct the current calculated full discharge capacity FDC of the battery according to the calculated full discharge capacity FDC and the true full discharge capacity FDC0 to obtain the corrected calculated full discharge capacity FDC. 、 。

[0084] S100: Estimate the current state of charge of the battery according to the corrected calculated full discharge capacity FDC 、 and the corrected calculated remaining capacity RMC. 、

[0085] Similarly, based on the data model, after obtaining the current battery parameters of the above battery, the true full discharge capacity FDC0 corresponding to the current voltage of the battery can be determined in the battery data model by using the current real-time current, real-time temperature, and number of charge and discharge cycles. Subsequently, correct the current calculated full discharge capacity FDC of the battery according to the calculated full discharge capacity FDC and the true full discharge capacity FDC0 to obtain the corrected calculated full discharge capacity FDC. 、 。

[0086] Specifically, as an example, correct the current calculated full discharge capacity FDC of the battery according to the calculated full discharge capacity FDC and the true full discharge capacity FDC0 to obtain the corrected calculated full discharge capacity FDC. 、 The specific steps are as follows:

[0087] Calculate the capacity difference between the calculated full discharge capacity FDC and the true full discharge capacity FDC0.

[0088] Determine the full discharge correction value RMCn per unit time according to the capacity difference.

[0089] When the calculated full discharge capacity FDC is greater than the true full discharge capacity FDC0, the calculated full discharge capacity FDC is reduced by the full discharge correction value RMCn per unit time to obtain the corrected calculated full discharge capacity FDC. 、 ;

[0090] When the calculated full discharge capacity FDC is less than the true full discharge capacity FDC0, the calculated full discharge capacity FDC is increased by the full discharge correction value RMCn per unit time to obtain the corrected calculated full discharge capacity FDC. 、 。

[0091] It can be seen that in the embodiment of the present application, while correcting the calculation of the remaining capacity RMC, the calculation of the full discharge capacity FDC is also corrected. Specifically, according to the difference between the currently calculated full discharge capacity FDC and the true full discharge capacity FDC0 obtained based on the data model, FDC approaches FDC0 once per second. That is, if FDC is greater than FDC0, then FDC decreases by a fixed value RMCn per second; if FDC is less than FDC0, then FDC increases by a fixed value RMCn per second, so as to correct the calculated full discharge capacity FDC in real time. 、 , that is to say, the calculated full discharge capacity FDC within a unit time 、 is all corrected.

[0092] In this way, the calculated full discharge capacity FDC and the calculated remaining capacity RMC finally used to calculate the SOC are both corrected capacities, that is, SOC = RMC 、 / FDC 、 . For example, SOC = (5000 - 5 - ((11000 - 5) * 10 / 10000)) / (11000 - 5) = 45.3842%. It can be seen that after adding the correction of RMC and FDC, the SOC has changed by 0.1248% (the gap with the true SOC has become smaller by 0.0248%). That is to say, after a certain correction time, the calculated RMC and FDC will gradually approach the true values, and the finally calculated SOC will also gradually approach the true values.

[0093] It should be emphasized here that in the present application, although the true remaining capacity RMC0 and the current true full discharge capacity FDC0 have been estimated through the data model, the true remaining capacity RMC0 and the current true full discharge capacity FDC0 are not directly used to calculate the SOC in the present application. Because the battery actually changes with voltage and current, the corresponding estimated true remaining capacity RMC0 and the true full discharge capacity FDC0 will also change, which will cause the estimated SOC to keep jittering. For stable processing, it is necessary to use the true capacity as a reference and use an algorithm to approach it, so as to obtain the final real-time = SOC, effectively improving the accuracy of the finally calculated real-time SOC.

[0094] Embodiment 2

[0095] Please refer to Figure 2 as shown, a method for estimating the state of charge based on a data model is provided for the charging state. The method includes the following steps:

[0096] S101: Obtain the current battery parameters of the battery, where the current battery parameters include the current voltage, the current real-time current, the real-time temperature, and the number of charge and discharge cycles.

[0097] The above-mentioned battery may refer to the battery of an electrical device in various application scenarios, and the present application does not make any limitations. When it is necessary to obtain the real-time SOC value of the battery for display or to participate in the decision-making of other functional modules, it is necessary to accurately obtain the real-time SOC value of the battery. First, the current battery parameters of the battery need to be obtained.

[0098] Among them, the process of a complete charge and discharge of the battery once is called a charge and discharge cycle. It can be understood that after multiple cycles, the battery life will decay, and the corresponding remaining capacity, full charge and discharge capacity, etc. will be different. That is to say, the current charge and discharge cycle times of the battery correspond to different decay degrees. Therefore, in the present application, in order to accurately evaluate the actual SOC situation of the battery during the charging process, it is also necessary to obtain the current charge and discharge cycle times of the battery.

[0099] It should be noted that the current battery may be in a discharging state or a charging state. When the current battery is in a discharging state, the current voltage is the discharging voltage and the current real-time current is the discharging current; when the current battery is in a charging state, the current voltage is the charging voltage and the current real-time current is the charging current. For example, in this Embodiment 2, it is in a charging state. Taking the charging state as an example, among the current battery parameters, the charge and discharge cycle times are the 111th cycle, the current battery temperature is 36°C, the current charging current is 9A, and the charging voltage is 3000 mV.

[0100] S102: Estimate the current true remaining capacity RMC0 of the battery in the battery data model by using the current voltage, real-time current, real-time temperature, and charge and discharge cycle times of the battery.

[0101] S103: Estimate the true remaining capacity RMC1 corresponding to the next correction target voltage by using the next correction target voltage, real-time current, real-time temperature, and charge and discharge cycle times of the battery.

[0102] After obtaining the current battery parameters of the above-mentioned battery, the true remaining capacity RMC0 corresponding to the current voltage of the battery and the true remaining capacity RMC1 corresponding to the next correction target voltage can be determined in the battery data model by using the current real-time current, real-time temperature, and charge and discharge cycle times.

[0103] It should be noted that in the present application, the data model of the battery is the same data model as that in the foregoing embodiment, and will not be described repeatedly here.

[0104] Specifically, compare the current voltage, the current real-time current, the real-time temperature, and the number of charge and discharge cycles with the data in the data model to determine the corresponding true remaining capacity RMC0 at the current charging voltage, the current real-time charging current, the real-time temperature, and the number of charge and discharge cycles. Compare the next target correction voltage, the current real-time charging current, the real-time temperature, and the number of charge and discharge cycles with the data in the data model to obtain the true remaining capacity RMC0 corresponding to the next target correction voltage at the current real-time current, the real-time temperature, and the number of charge and discharge cycles.

[0105] It should be noted that, as described above, after establishing the model, it is possible to know the remaining capacity corresponding to different charging voltages under different conditions. For example, it is known that under a certain condition, the true remaining capacity at 3500 mV and the true remaining capacity at 3600 mV. Then, for the charging process, the voltage will become higher and higher. When the current is 3500 mV, the next target correction voltage is 3600 mV. Therefore, through the data model, it is also possible to know the true remaining capacity corresponding to the next target correction voltage.

[0106] For example, using the 110th cycle, the real-time temperature of 36 °C, the current discharge current of 9 A, and the current charging voltage of 3500 mV, determine the true remaining capacity RMC0 corresponding to the current charging voltage of 3500 mV. Using the 110th cycle, the real-time temperature of 36 °C, and the current discharge current of 9 A, determine the true remaining capacity RMC1 corresponding to the next target correction of 3600 mV.

[0107] S104: Calculate the current calculated remaining capacity RMC of the battery based on ampere-hour integration, and determine the current calculated full charge capacity FCC according to the previous charging result.

[0108] It should be noted that in the embodiments of the present application, the calculated remaining capacity RMC is also obtained based on ampere-hour integration. It is also worth emphasizing that the currently calculated calculated remaining capacity RMC is also calculated using ampere-hour integration. This RMC = A*H (real-time current * time). Due to many factors such as current measurement accuracy and time calculation deviation, there will be a certain deviation between the currently calculated calculated remaining capacity RMC and the true remaining capacity RMC0. Therefore, for the charging process, it is also necessary to correct the deviation of the calculated remaining capacity RMC later to gradually bring the two closer.

[0109] Among them, the calculated full charge capacity FCC is calculated from the previous discharge. Theoretically, the charged capacity and the discharged capacity are the same. Therefore, in the present application, the total capacity of the previous discharge is used as the theoretical value of the full discharge capacity for the next charge, that is, the previous calculated full discharge capacity FDC is used as the current calculated full charge capacity FCC.

[0110] S105: Calculate the self-charging rate K2 of the next discharge stage of the battery according to the calculated remaining capacity RMC, the real remaining capacity RMC0 corresponding to the current voltage and the real remaining capacity RMC1 of the next corrected target voltage.

[0111] S106: Using the self-charging rate K2, correcting the calculated remaining capacity RMC to obtain a corrected calculated remaining capacity RMC 、 .

[0112] In one embodiment, the self-charging rate K2 of the battery in the next stage is calculated as follows:

[0113] K2= (RMC1–RMC) * A / (RMC1–RMC0);

[0114] As mentioned above, K2 represents the self-charging rate, RMC represents the calculated remaining capacity, RMC1 represents the actual remaining capacity of the next corrected target voltage, RMC0 represents the actual remaining capacity corresponding to the current voltage, and A represents the amplification factor. Specifically, considering the unit problem, for the convenience of calculation, A can be 1000. After RMC is corrected using the self-charging rate K2, RMC 、 =K2*RMC / A; where RMC 、 represents the corrected calculated remaining capacity, K2 represents the self-charging rate, RMC represents the calculated remaining capacity, and A represents the amplification factor.

[0115] S107: Calculating the full charge capacity FCC and correcting the remaining capacity RMC 、 , estimating the current state of charge of the battery.

[0116] Thus, from SOC = RMC / FCC, after correcting RMC, the current real-time SOC can be calculated by calculating the full charge capacity FCC and correcting the remaining capacity RMC. 、 get.

[0117] It should be noted that in one embodiment, during the charging state, while adding the correction for calculating the remaining capacity RMC, the correction for calculating the full charge capacity FCC can also be added. The process of correcting the calculated full charge capacity FCC is similar to the process of correcting the calculated full discharge capacity FDC in the foregoing embodiment. Specifically, based on the data model, the true remaining full charge capacity FCC0 is first obtained. Specifically, the capacity difference between the calculated full charge capacity FCC and the true full charge capacity FCC0 is calculated; according to the capacity difference between the calculated full charge capacity FCC and the true full charge capacity FCC0, the full charge correction value RMCm per unit time is determined; when the calculated full charge capacity RMCm is greater than the true full charge capacity FCC0, the calculated full discharge capacity FCC is reduced by the full charge correction value RMCm per unit time to obtain the corrected calculated full charge capacity FCC 、 ; when the calculated full charge capacity FCC is less than the true full charge capacity FCC0, the calculated full charge capacity FCC is increased by the full charge correction value RMCm per unit time to obtain the corrected calculated full charge capacity FCC 、 , it can be seen that compared with the process of correcting the calculated full discharge capacity FDC, the difference is that one is the discharge state and the other is the charging state. For more details, reference can be made to the correction of the calculated full discharge capacity FDC in the foregoing embodiment, and specific descriptions are not repeated here

[0118] After a certain correction time, the calculated remaining capacity RMC and the calculated full charge capacity FCC will gradually approach the true values, and the finally calculated SOC will also gradually approach the true value

[0119] It should also be emphasized here that in the present application, although the true remaining capacity RMC0 and the current true full charge capacity FCC0 can be estimated through the data model, the true remaining capacity RMC0 and the current true full discharge capacity FCC0 are not directly used to calculate the SOC in the present application. Because during the charging state, the battery actually changes with the voltage and current, and the corresponding estimated true remaining capacity RMC0 and the true full charge capacity FDC0 will also change, which will cause the estimated SOC to jitter continuously. For stable processing, the true capacity is used as a reference and an algorithm is used to approximate, so as to obtain the final real-time SOC, effectively improving the accuracy of the finally calculated real-time SOC

[0120] In summary, a method for estimating the state of charge based on a data model is proposed. This method for estimating the state of charge can be used to estimate the state of charge during the charging or discharging process of a battery. By combining the data model, the self-discharge rate and self-charging rate during the charging or discharging process of the battery are calculated. Then, the self-discharge rate is used to correct the remaining capacity involved in the SOC calculation during the discharging process, making the final SOC closer to the actual situation. The self-charging rate is used to correct the remaining capacity involved in the SOC calculation during the charging process, making the final SOC closer to the actual situation.

[0121] It should be understood that the magnitudes of the sequence numbers of the steps in the above embodiments do not imply the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0122] Embodiment 3

[0123] Figure 3 The principle block diagram of a state-of-charge estimation device based on a data model corresponding one-to-one to the state-of-charge estimation method based on a data model in Embodiments 1 and 2 is shown. As Figure 3 shown, the state-of-charge estimation based on the data model includes an estimation module 10, a calculation module 20, a correction module 30, and a determination module 40. Among them:

[0124] In one embodiment, the state-of-charge estimation device based on the data model is used for estimating the SOC in the discharging state. Specifically:

[0125] The estimation module 10 is configured to use the current voltage, real-time current, real-time temperature, and charge-discharge cycle number of the battery to estimate the true remaining capacity RMC0 of the battery at present in the battery data model; use the next correction target voltage, real-time current, real-time temperature, and charge-discharge cycle number of the battery to estimate the true remaining capacity RMC1 corresponding to the next correction target voltage;

[0126] The calculation module 20 is configured to calculate the calculated remaining capacity RMC of the battery based on ampere-hour integration, and determine the current calculated full-discharge capacity FDC according to the previous charging result; calculate the self-discharge rate K1 of the next discharging stage of the battery according to the calculated remaining capacity RMC, the true remaining capacity RMC0 corresponding to the current voltage, and the true remaining capacity RMC1 of the next correction target voltage;

[0127] The correction module 30 is configured to use the self-discharge rate K1 to correct the calculated remaining capacity RMC to obtain the corrected calculated remaining capacity RMC 、 ;

[0128] The determination module 40 is configured to pass through the calculated full-discharge capacity FDC and the corrected calculated remaining capacity RMC、 , determine the current state of charge of the battery.

[0129] In one embodiment, the estimation module 10 is specifically configured to:

[0130] When using the current voltage, the current real-time current, the real-time temperature, and the number of charge and discharge cycles, in the battery data model, determine the current true full discharge capacity of the battery;

[0131] According to the calculated full discharge capacity and the true full discharge capacity, correct the currently calculated full discharge capacity of the battery to obtain a corrected calculated full discharge capacity;

[0132] Estimate the current state of charge of the battery according to the corrected calculated full discharge capacity and the corrected calculated remaining capacity.

[0133] In one embodiment, the calculation module 20 is specifically configured to calculate the self-discharge rate in the following manner:

[0134] K1 = (RMC – RMC1) * A / (RMC0 – RMC1);

[0135] Wherein, K1 represents the self-discharge rate, RMC represents the calculated remaining capacity, RMC1 represents the true remaining capacity of the next corrected target voltage, RMC0 represents the true remaining capacity corresponding to the current voltage, and A represents the amplification factor.

[0136] In one embodiment, the correction module 30 is specifically configured to obtain the corrected calculated remaining capacity in the following manner:

[0137] RMC 、 = K1 * RMC / A;

[0138] Wherein, RMC 、 represents the corrected calculated remaining capacity, K1 represents the self-discharge rate, RMC represents the calculated remaining capacity, and A represents the amplification factor.

[0139] In one embodiment, the correction module 30 is specifically configured to:

[0140] Calculate the capacity difference between the calculated full discharge capacity and the true full discharge capacity;

[0141] Determine the full discharge correction value per unit time according to the capacity difference;

[0142] When the calculated full discharge capacity is greater than the true full discharge capacity, reduce the calculated full discharge capacity by the full discharge correction value per unit time to obtain the corrected calculated full discharge capacity;

[0143] When the calculated full discharge capacity is less than the true full discharge capacity, increase the calculated full discharge capacity by the full discharge correction value per unit time to obtain a corrected calculated full discharge capacity.

[0144] In one embodiment, the data model is obtained in advance in the following manner:

[0145] Record the charge and discharge data of the battery in real time. The charge and discharge data includes the number of charge and discharge cycles, the temperature corresponding to each cycle, the charge and discharge voltage, the charge and discharge current data, and record the remaining capacity and full discharge capacity of the battery corresponding to the charge and discharge data.

[0146] Establish the data model based on the charge and discharge data of the battery and the remaining capacity and full discharge capacity of the battery corresponding to the charge and discharge data.

[0147] In one embodiment, a state of charge estimation device based on a data model is used for estimating the state of charge SOC. Specifically:

[0148] The estimation module 10 is configured to use the current voltage, real-time current, real-time temperature, and charge and discharge cycle number of the battery to estimate the current true remaining capacity RMC0 of the battery in the battery data model; use the next corrected target voltage, real-time current, real-time temperature, and charge and discharge cycle number of the battery to estimate the true remaining capacity RMC1 corresponding to the next corrected target voltage.

[0149] The calculation module 20 is configured to calculate the current calculated remaining capacity RMC of the battery based on ampere-hour integration, and calculate the current calculated full charge capacity FCC according to the previous discharge result; calculate the self-charging rate K2 of the next charging stage of the battery according to the calculated remaining capacity RMC, the true remaining capacity RMC0 corresponding to the current voltage, and the true remaining capacity RMC1 of the next corrected target voltage.

[0150] The correction module 30 is configured to use the self-charging rate K2 to correct the calculated remaining capacity RMC to obtain a corrected calculated remaining capacity RMC 、 ;

[0151] The determination module 40 is configured to determine the current state of charge of the battery through the calculated full charge capacity FCC and the corrected calculated remaining capacity RMC 、 , to determine the current state of charge of the battery.

[0152] In one embodiment, the calculation module 20 is specifically configured to calculate the self-charging rate in the following manner:

[0153] K2 = (RMC1 – RMC) * A / (RMC1 – RMC0);

[0154] Wherein, K2 represents the self-discharge rate, RMC represents the calculated remaining capacity, RMC1 represents the true remaining capacity of the next corrected target voltage, RMC0 represents the true remaining capacity corresponding to the current voltage, and A represents the amplification factor.

[0155] It should be noted that the functions or steps implemented by the state of charge estimation device based on the data model correspond one by one to the discharge state or charge state process of the state of charge estimation method based on the data model in the foregoing embodiments. For details, reference can be made to the description of the foregoing method embodiments, which will not be repeated here.

[0156] Embodiment 4

[0157] This embodiment provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the state of charge estimation method based on the data model in Embodiment 1 or 2. To avoid repetition, it will not be elaborated here. Alternatively, when the computer program is executed by a processor, it implements the functions of each module in the state of charge estimation device in Embodiment 3. To avoid repetition, it will not be elaborated here.

[0158] It can be understood that the computer-readable storage medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signals, telecommunication signals, etc.

[0159] Embodiment 5

[0160] Figure 4 is a schematic diagram of a computer device provided by an embodiment of the present application. As Figure 4 shown, the computer device 60 in this embodiment includes: a processor 61, a memory 62, and a computer program 63 stored in the memory 62 and executable on the processor 61. When the processor 61 executes the computer program 63, it implements the steps of the state of charge estimation method based on the data model in Embodiment 1 above, such as Figure 1 the steps S10 to S70, steps S101 - S107 shown. Alternatively, when the processor 61 executes the computer program 63, it implements the functions of each module in the state of charge estimation device based on the data model in Embodiment 3 above, such as Figure 3 the functions of the estimation module 10, calculation module 20, correction module 30, determination module 40 and other modules shown.

[0161] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above-mentioned division of each functional unit and module is used as an example. In actual applications, the above-mentioned functions can be allocated to different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above.

[0162] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A state of charge estimation method for the discharge state of a battery, characterized in that, it includes: Using the current voltage, real-time current, real-time temperature and charge-discharge cycle times of the battery, in the battery data model, estimate the current true remaining capacity of the battery. The battery data model is a data model established based on the charge-discharge data of the battery, and the remaining capacity and full discharge capacity corresponding to the battery under the charge-discharge data; Using the next corrected target voltage, real-time current, real-time temperature and charge-discharge cycle times of the battery, in the battery data model, estimate the true remaining capacity corresponding to the next corrected target voltage; Calculate the current calculated remaining capacity of the battery based on ampere-hour integration, and determine the current calculated full discharge capacity according to the previous charging result; Calculate the self-discharge rate of the next discharge stage of the battery according to the calculated remaining capacity, the true remaining capacity corresponding to the current voltage and the true remaining capacity of the next corrected target voltage; Using the self-discharge rate, correct the calculated remaining capacity to obtain the corrected calculated remaining capacity RMC 、 ; Estimate the current state of charge of the battery through the calculated full discharge capacity and the corrected calculated remaining capacity; Calculate the self-discharge rate of the next discharge stage of the battery in the following way: K1 = (RMC – RMC1) * A / (RMC0 – RMC1); where, K1 represents the self-discharge rate, RMC represents the calculated remaining capacity, RMC1 represents the true remaining capacity of the next corrected target voltage, RMC0 represents the true remaining capacity corresponding to the current voltage, and A represents the amplification factor.

2. The state of charge estimation method according to claim 1, characterized in that, The estimating the current state of charge of the battery through the calculated full discharge capacity and the corrected calculated remaining capacity includes: Using the current voltage, current real-time current, real-time temperature and charge-discharge cycle times, in the battery data model, determine the current true full discharge capacity of the battery; According to the calculated full discharge capacity and the true full discharge capacity, correct the current calculated full discharge capacity of the battery to obtain the corrected calculated full discharge capacity; Estimate the current state of charge of the battery according to the corrected calculated full discharge capacity and the corrected calculated remaining capacity.

3. The state of charge estimation method according to claim 1, characterized in that, The corrected calculated remaining capacity is obtained in the following way: RMC 、 = K1 * RMC / A; Among them, RMC 、 represents the corrected calculated remaining capacity, K1 represents the self-discharge rate, RMC represents the calculated remaining capacity, and A represents the amplification factor.

4. The state of charge estimation method according to claim 2, characterized in that, The correcting the current calculated full discharge capacity of the battery according to the calculated full discharge capacity and the true full discharge capacity to obtain the corrected calculated full discharge capacity includes: Calculate the capacity difference between the calculated full discharge capacity and the true full discharge capacity; Determine the full discharge correction value per unit time according to the capacity difference; When the calculated full discharge capacity is greater than the true full discharge capacity, make the calculated full discharge capacity decrease by the full discharge correction value per unit time to obtain the corrected calculated full discharge capacity; When the calculated full discharge capacity is less than the true full discharge capacity, make the calculated full discharge capacity increase by the full discharge correction value per unit time to obtain the corrected calculated full discharge capacity.

5. The state of charge estimation method according to any one of claims 1-4, characterized in that, The battery data model is obtained in advance in the following manner: The charge and discharge data of the battery are recorded in real time. The charge and discharge data include the number of charge and discharge cycles, the temperature corresponding to each cycle, the charge and discharge voltage, the charge and discharge current data, and the remaining capacity and full discharge capacity of the battery corresponding to the recorded charge and discharge data. Based on the charge and discharge data of the battery, and the remaining capacity and full discharge capacity of the battery corresponding to the charge and discharge data, the battery data model is established.

6. A state of charge estimation method for the charging state of a battery Characterized in that It includes: Using the current voltage, real-time current, real-time temperature and number of charge and discharge cycles of the battery, in the battery data model, estimate the true remaining capacity of the battery at present. The battery data model is a data model established based on the charge and discharge data of the battery, and the remaining capacity and full discharge capacity of the battery corresponding to the charge and discharge data. Using the next correction target voltage, real-time current, real-time temperature and number of charge and discharge cycles of the battery, estimate the true remaining capacity corresponding to the next correction target voltage. Based on ampere-hour integration, calculate the calculated remaining capacity of the battery at present, and determine the calculated full charge capacity at present according to the previous discharge result. According to the calculated remaining capacity, the true remaining capacity corresponding to the current voltage and the true remaining capacity of the next correction target voltage, calculate the self-charging rate of the next charging stage of the battery. Using the self-charging rate, correct the calculated remaining capacity to obtain the corrected calculated remaining capacity. Through the calculated full charge capacity and the corrected calculated remaining capacity, determine the state of charge of the battery at present. The self-charging rate of the next charging stage of the battery is calculated in the following manner: K2 = (RMC1–RMC) * A / (RMC1–RMC0); where K2 represents the self-charging rate, RMC represents the calculated remaining capacity, RMC1 represents the true remaining capacity of the next correction target voltage, RMC0 represents the true remaining capacity corresponding to the current voltage, and A represents the amplification factor.

7. A computer device, including a memory, a processor, and a computer program stored in the memory and operable on the processor Characterized in that When the processor executes the computer program, it implements the steps of the state of charge estimation method according to any one of claims 1 to 6.

8. A computer-readable storage medium storing a computer program Characterized in that When the computer program is executed by the processor, it implements the steps of the state of charge estimation method according to any one of claims 1 to 6.

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