A method for correcting soc-ocv of an electric vehicle

Abstract

The application discloses a kind of electric vehicle SOC-OCV's correction method, comprising: SOC-OCV correction is carried out to power battery, and after SOC-OCV correction, the ΔSOC1 value needing correction is stored;During discharging, the ΔSOC1 value is corrected according to the capacity discharged after SOC is 0%;During charging, the ΔSOC1 value is corrected according to the jump amplitude of SOC.The electric vehicle SOC-OCV's correction method of the application, after SOC-OCV correction, the ΔSOC1 value needing correction is stored, and the ΔSOC1 value is corrected during charging and discharging, to prevent the next error correction current SOC 原 ;It can eliminate the difference between the calibrated SOC-OCV parameter and the current battery pack SOC-OCV parameter;SOC-OCV correction is carried out only after confirming the real SOC-OCV parameter value of battery pack, effectively avoiding SOC-OCV false correction.

Description

Technical Field

[0001] This invention relates to the field of battery management system technology, and more particularly to a correction method for a State of Charge (SOC)-Occupancy Vehicle (OCV) in electric vehicles. Background Technology

[0002] Currently, the parameters in the SOC (State of Charge) algorithms for domestic pure electric vehicles are calibrated using a certain number of samples. However, limitations in domestic lithium iron phosphate battery manufacturing capabilities mean that the calibrated parameters cannot guarantee an error of ≤4% compared to every battery pack in mass production. Furthermore, due to time and resource constraints, it's impossible to calibrate the SOC-OCV parameters for every battery pack. Additionally, the voltage acquisition accuracy of mainstream domestic BMS (Battery Management Systems) is currently ±3‰, and the voltage acquisition accuracy of BMS is not entirely consistent.

[0003] Therefore, there is an urgent need for a correction method for electric vehicle SOC-OCV. Summary of the Invention

[0004] The purpose of this invention is to provide a method for correcting the SOC-OCV of an electric vehicle to solve the problems in the prior art and eliminate the difference between the calibrated SOC-OCV parameters and the current battery pack SOC-OCV parameters.

[0005] This invention provides a method for correcting the state of charge (SOC) to open-vehicle (OCV) state of an electric vehicle, comprising:

[0006] Perform SOC-OCV correction on the power battery, and after SOC-OCV correction, store the △SOC1 value that needs to be corrected;

[0007] During the discharge process, the value of ΔSOC1 is corrected based on the capacity discharged by the battery pack after the SOC is 0%.

[0008] During the charging process, the value of ΔSOC1 is corrected according to the amplitude of the SOC jump.

[0009] The method for correcting the SOC-OCV of an electric vehicle as described above, preferably, involves correcting the SOC-OCV of the power battery and storing the ΔSOC1 value to be corrected after the SOC-OCV correction, specifically including:

[0010] After the vehicle controller is activated, it is determined whether the battery resting time is greater than the preset resting time threshold.

[0011] If so, the SOC1 value corresponding to the current lowest single cell voltage and the current lowest cell temperature is obtained by linear interpolation in the pre-calibrated MAP table. The MAP table is used to characterize the relationship between the lowest single cell voltage, the lowest cell temperature and the SOC1 value.

[0012] Determine whether the SOC1 value corresponding to the current lowest single cell voltage and the current lowest cell temperature is less than the first preset SOC threshold;

[0013] If so, then determine SOC. 原 - Is SOC1 greater than the first preset amplitude, where SOC 原 Used to indicate the SOC value of the battery in real time before it is left to stand;

[0014] If so, then by using the formula △SOC1=SOC 原 -SOC1, calculate the △SOC1 value that needs to be corrected, and store the △SOC1 value that needs to be corrected.

[0015] In the electric vehicle SOC-OCV correction method described above, preferably, the preset resting time threshold is 0.75h-1.5h, the first preset SOC threshold is 13%-20%, and the first preset amplitude is 3%-6%.

[0016] The electric vehicle SOC-OCV correction method described above, preferably, includes, in addition to, performing SOC-OCV correction on the power battery and storing the ΔSOC1 value to be corrected after SOC-OCV correction, the method further includes:

[0017] If the battery resting time is not greater than the preset resting time threshold, or the SOC1 value corresponding to the current lowest single cell voltage and the current lowest battery temperature is not less than the first preset SOC threshold, or SOC 原 If SOC1 is not greater than the first preset amplitude, exit correction mode.

[0018] The electric vehicle SOC-OCV correction method described above preferably includes, in the step of correcting the ΔSOC1 value based on the capacity discharged by the battery pack after the SOC reaches 0% during the discharge process, specifically comprising:

[0019] In discharge mode, determine whether the OCV correction flag is 1;

[0020] If so, then determine SOC. 原 Is it less than or equal to the second preset SOC threshold?

[0021] If so, determine whether the battery pack can discharge to the minimum single cell voltage to reach the preset voltage threshold after the SOC is 0%.

[0022] If so, record the discharge capacity of the battery from 0% SOC to the point where the lowest single cell voltage reaches the preset voltage threshold.

[0023] Based on discharge capacity, rated capacity, and battery health, the formula SOC2 = A1 / (C) is used. 额定 *SOH) calculates SOC2, where SOC2 represents the true SOC when SOC is displayed as 0%, A1 represents the discharge capacity, and C 额定 The rated capacity is indicated by SOH, and the battery health status is indicated by SOH.

[0024] Using the formula △SOC 1-1 =SOC 原 -SOC1-SOC2, calculate the correction result of △SOC1 value;

[0025] If SOC 原 If the value is not less than or equal to the second preset SOC threshold, then during the discharge process, it is determined whether the ΔSOC1 value needs to be corrected based on the discharge current, discharge time, and battery pack voltage difference.

[0026] The above-described correction method for SOC-OCV of electric vehicles, wherein, preferably, in SOC... 原 If the value is not less than or equal to the second preset SOC threshold, during the discharge process, determining whether to correct the ΔSOC1 value based on the discharge current, discharge time, and battery pack voltage difference specifically includes:

[0027] Determine whether the following conditions are met: I ≤ 0.1C, t ≥ 10s, ΔV ≤ 20mV, or I > 2C, t ≥ 5s, ΔV ≤ I + 50mV, where I represents the discharge current, C represents the discharge rate, t represents the discharge time, and ΔV represents the maximum single-cell voltage V. max and the lowest single cell voltage V min The pressure difference;

[0028] If satisfied, then use the formula △SOC 1-2 =0, calculate the correction result of △SOC1 value, that is, no correction is needed for SOC-OCV;

[0029] If the conditions are not met, exit correction mode.

[0030] In the electric vehicle SOC-OCV correction method described above, preferably, the second preset SOC threshold is 25%-35%, and the preset voltage threshold is 2.1V-2.5V.

[0031] The electric vehicle SOC-OCV correction method described above, preferably, further includes correcting the ΔSOC1 value based on the capacity discharged by the battery pack after the SOC reaches 0% during the discharge process, and further includes:

[0032] If the OCV correction flag is not 1, or if the battery pack cannot discharge to the minimum single cell voltage to reach the preset voltage threshold after the SOC is 0%, then exit the correction mode.

[0033] The electric vehicle SOC-OCV correction method described above preferably includes, in the charging process, correcting the ΔSOC1 value based on the SOC jump amplitude, specifically comprising:

[0034] In discharge mode, determine whether the OCV correction flag is 1;

[0035] If so, can the battery be charged to 99% SOC?

[0036] If the battery can be charged to 99% SOC, then adjust the SOC to 100%.

[0037] If the battery cannot be charged to 99% SOC, then the formula ΔSOC3 = 100% - SOC can be used. 跳变 Calculate the SOC jump amplitude ΔSOC3 before reaching full charge, where SOC 跳变 This represents the SOC value before jumping to 100%;

[0038] Using the formula △SOC 1-3 =SOC 原 -SOC1-△SOC3, calculate the corrected value of △SOC1.

[0039] The electric vehicle SOC-OCV correction method described above, preferably, includes, during the charging process, correcting the ΔSOC1 value based on the SOC jump amplitude, further comprising:

[0040] If the OCV correction flag is not 1, exit correction mode.

[0041] This invention provides a method for correcting the State of Charge (SOC) to Offset Volume (OCV) of an electric vehicle. After an SOC-OCV correction occurs, the method stores the ΔSOC1 value that needs correction and corrects it online during subsequent discharge or charging processes to prevent incorrect correction of the current SOC in the future. 原 It can eliminate the difference between the calibrated SOC-OCV parameters and the current SOC-OCV parameters of the battery pack; SOC-OCV correction can only be performed after the actual SOC-OCV parameter values ​​of the battery pack are confirmed online, which can effectively avoid incorrect SOC-OCV correction. Attached Figure Description

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described below with reference to the accompanying drawings, wherein:

[0043] Figure 1 A flowchart illustrating an embodiment of the electric vehicle SOC-OCV correction method provided by the present invention;

[0044] Figure 2 Logic diagram modified for SOC-OCV;

[0045] Figure 3 The logic diagram for correcting the ΔSOC1 value during the discharge process;

[0046] Figure 4 The logic diagram for correcting the ΔSOC1 value during the charging process. Detailed Implementation

[0047] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The descriptions of the exemplary embodiments are merely illustrative and are in no way intended to limit the present disclosure or its application or use. The present disclosure may be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided so that the present disclosure will be thorough and complete, and will fully express the scope of the disclosure to those skilled in the art. It should be noted that, unless specifically stated otherwise, the relative arrangement of components and steps, the composition of materials, numerical expressions, and values ​​set forth in these embodiments should be interpreted as exemplary only and not as limiting.

[0048] The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. Terms such as “including” or “contains” mean that the element preceding the term encompasses the element listed after it, and do not exclude the possibility of encompassing other elements as well. Terms such as “above” and “below” are used only to indicate relative positional relationships; when the absolute position of the described object changes, this relative positional relationship may also change accordingly.

[0049] In this disclosure, when a specific component is described as being located between a first component and a second component, an intermediary component may or may not be present between the specific component and the first or second component. When a specific component is described as connecting to other components, the specific component may be directly connected to the other components without having an intermediary component, or it may not be directly connected to the other components but may have an intermediary component.

[0050] All terms used in this disclosure (including technical or scientific terms) have the same meaning as understood by one of ordinary skill in the art to which this disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary, such as a dictionary, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and not as having an idealized or highly formalized meaning, unless expressly defined herein.

[0051] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0052] Currently, the main strategies for estimating battery SOC include: open-circuit voltage method, ampere-hour integration method, artificial neural network method, and Kalman filtering method. The industry primarily uses ampere-hour integration supplemented by OCV correction algorithms for battery SOC estimation; however, based on the fact that battery pack consistency is within a normal range, the SOC estimation error can be controlled within ±4%.

[0053] Since the industry standard for battery SOC-OCV correction is generally based on V... min T min After obtaining the current OCV value from the table, the current SOC value is directly or indirectly corrected (accelerating the SOC decrease during discharge). It is assumed that the error between the parameters calibrated by the SOC algorithm and the current battery pack is ≤4%, and no judgment is made regarding whether the current battery pack has tolerance faults before performing SOC-OCV correction, which may lead to incorrect repairs.

[0054] like Figure 1 As shown, the electric vehicle SOC-OCV correction method provided in this embodiment specifically includes the following steps in actual implementation:

[0055] Step S1: Perform SOC-OCV correction on the power battery, and after SOC-OCV correction, store the ΔSOC1 value that needs to be corrected.

[0056] like Figure 2 As shown, in one embodiment of the electric vehicle SOC-OCV correction method of the present invention, step S1 may specifically include:

[0057] Step S11: After the vehicle controller (VCU) is activated, determine whether the battery resting time is greater than the preset resting time threshold.

[0058] The preset resting time threshold is 0.75h-1.5h, for example, 1h. It should be noted that the present invention does not specifically limit the preset resting time threshold.

[0059] Step S12: If yes, then in the pre-calibrated MAP table, the SOC1 value corresponding to the current lowest single cell voltage and the current lowest battery temperature is obtained by looking up the table through linear interpolation. The MAP table is used to characterize the relationship between the lowest single cell voltage, the lowest battery temperature and the SOC1 value.

[0060] The vehicle controller collects the current lowest single-cell voltage and the current lowest battery temperature, and the MAP table is stored in the vehicle controller. Table 1 shows an example of the MAP table.

[0061] Table 1 MAP Table

[0062]

[0063]

[0064] Step S13: Determine whether the SOC1 value corresponding to the current lowest single cell voltage and the current lowest cell temperature is less than the first preset SOC threshold.

[0065] The first preset SOC threshold is 13%-20%, for example, 15%. It should be noted that the present invention does not specifically limit the first preset SOC threshold.

[0066] Step S14: If yes, then determine SOC. 原 - Is SOC1 greater than the first preset amplitude, where SOC 原 Used to indicate the SOC value of the battery in real time before it is left to stand.

[0067] The first preset amplitude is 3%-6%, for example, 4%. It should be noted that the present invention does not specifically limit the first preset amplitude.

[0068] Step S15: If so, then use the formula △SOC1=SOC 原 -SOC1, calculate the △SOC1 value that needs to be corrected, and store the △SOC1 value that needs to be corrected.

[0069] Here, △SOC1 is not necessarily accurate, because SOC1 comes from V. min T min The table shows the results of previous battery pack calibrations, which may not perfectly match the current SOC-OCV data of the battery pack. Therefore, ΔSOC1 needs to be corrected during subsequent discharge or charging processes.

[0070] For example, if SOC 原 =50%, and by looking up the table, SOC1 = 18%, then △SOC1 = SOC 原 -SOC1=50%-18%=32%.

[0071] Furthermore, such as Figure 2 As shown, in some embodiments of the present invention, step S1 further includes:

[0072] Step S16: If the battery resting time is not greater than a preset resting time threshold, or the SOC1 value corresponding to the current lowest single-cell voltage and the current lowest battery temperature is not less than a first preset SOC threshold, or the SOC... 原If SOC1 is not greater than the first preset amplitude, exit correction mode.

[0073] Step S2: During the discharge process, the value of ΔSOC1 is corrected based on the capacity discharged by the battery pack after the SOC is 0%.

[0074] like Figure 3 As shown, in one embodiment of the electric vehicle SOC-OCV correction method of the present invention, step S2 may specifically include:

[0075] Step S21: In discharge mode, determine whether the OCV correction flag is 1.

[0076] Step S22: If yes, then determine SOC. 原 Is it less than or equal to the second preset SOC threshold?

[0077] The second preset SOC threshold is 25%-35%, for example, 30%. It should be noted that the present invention does not specifically limit the second preset SOC threshold.

[0078] Step S23: If yes, then determine whether the battery pack can discharge to the minimum single cell voltage reaching the preset voltage threshold after the SOC is 0%.

[0079] The preset voltage threshold is 2.1V-2.5V, for example, 2.3V. It should be noted that the present invention does not specifically limit the preset voltage threshold.

[0080] Step S24: If yes, record the discharge capacity of the battery from 0% SOC to the minimum single cell voltage reaching the preset voltage threshold.

[0081] Step S25: Based on the discharge capacity, rated capacity, and battery health, use the formula SOC2 = A1 / (C 额定 *SOH) calculates SOC2, where SOC2 represents the true SOC when SOC is displayed as 0%, A1 represents the discharge capacity, and C 额定 The rated capacity is indicated by Ah, and SOH indicates the battery health status.

[0082] Step S26: Using the formula △SOC 1-1 =SOC 原 -SOC1-SOC2, calculate the corrected value of △SOC1.

[0083] Based on the capacity released after SOC reaches 0%, the required correction SOC2 is calculated to correct the original ΔSOC1.

[0084] In one embodiment of the present invention, the rated capacity (C) of the battery pack 额定The capacity is 100Ah. During the discharge process, when the vehicle enters discharge mode, the State of Charge (SOC) is recorded. 原 After reaching 0%, the continuously released capacity is A1, and SOC2 = A1 / (C 额定 *SOH)=10Ah / (100%*100Ah)=10%.

[0085] The next time the SOC-OCV correction occurs, △SOC1-1=SOC 原 -SOC1-SOC2=50%-18%-10%=22%.

[0086] So the next time SOC-OCV correction occurs, i.e., SOC... 原 When it is 50%, the corrected SOC1 is 28% (50% - 22% = 28%).

[0087] Step S27, if SOC 原 If the value is not less than or equal to the second preset SOC threshold, then during the discharge process, it is determined whether the ΔSOC1 value needs to be corrected based on the discharge current, discharge time, and battery pack voltage difference.

[0088] like Figure 3 As shown, in one embodiment of the electric vehicle SOC-OCV correction method of the present invention, in SOC 原 If the value is not less than or equal to the second preset SOC threshold, step S27 may specifically include:

[0089] Step S271: Determine whether the following conditions are met: I≤0.1C, t≥10s, ΔV≤20mV, or I>2C, t≥5s, ΔV≤I+50mV.

[0090] Where I represents the discharge current, C represents the rate of discharge (e.g., if the rated capacity of the battery pack is 100Ah, then 1C = 100A, and the battery pack current I = 0.1C = 10A); t represents the discharge time, ΔV = V max -V min That is, ΔV represents the highest single-cell voltage V. max and the lowest single cell voltage V min The pressure difference. In the formula △V≤I+50mV, I only takes the numerical value, not the unit; that is, only the value of I is used.

[0091] Step S272: If satisfied, then use the formula △SOC 1-2 =0, calculate the correction result of △SOC1 value, that is, no correction is needed for SOC-OCV.

[0092] During the discharge process, if SOC 原 It was not discharged to 0%, but the discharge current I < 0.1C and t ≥ 10s are satisfied. According to ΔV = Vmax -V min ≤20mV, or discharge current I≥2C (1.5C in the table), t≥5s, ΔV=V max -V min If the voltage is ≤I+50mV, it can be confirmed that there is no large voltage difference problem in the current battery system, and SOC-OCV does not need to be corrected, and △SOC1=0%.

[0093] The consistency of the battery pack is determined by judging whether the voltage difference of the battery pack is within a very small range under the conditions of satisfying the discharge current and discharge time. If the consistency of the battery pack is very good, then no correction of SOC-OCV is required. If a correction is made to △SOC1, then it is an incorrect correction.

[0094] Step S273: If the condition is not met, exit the correction mode.

[0095] Furthermore, such as Figure 3 As shown, in one embodiment of the electric vehicle SOC-OCV correction method of the present invention, step S2 further includes:

[0096] Step S28: If the OCV correction flag is not 1, or the battery pack cannot discharge to the minimum single cell voltage reaching the preset voltage threshold after the SOC is 0%, then exit the correction mode.

[0097] Step S3: During the charging process, the value of △SOC1 is corrected according to the jump amplitude of SOC.

[0098] like Figure 4 As shown, in one embodiment of the electric vehicle SOC-OCV correction method of the present invention, step S3 may specifically include:

[0099] Step S31: In discharge mode, determine whether the OCV correction flag is 1.

[0100] Step S32: If yes, can the battery be charged to 99% SOC?

[0101] Step S33: If the battery can be charged to 99% SOC, then adjust the SOC to 100%.

[0102] Step S34: If the battery cannot be charged to 99% SOC, then use the formula △SOC3 = 100% - SOC 跳变 Calculate the SOC jump amplitude ΔSOC3 before reaching full charge, where SOC 跳变 This represents the SOC value before jumping to 100%.

[0103] Step S35: Using the formula △SOC 1-3 =SOC 原-SOC1-△SOC3, calculate the corrected value of △SOC1.

[0104] In one embodiment of the present invention, after the electric vehicle begins charging, the State of Charge (SOC) jumps directly from 90% to 100% (fully charged state) during the charging process. That is, ΔSOC3 = 100% - 90% = 10%, from which ΔSOC is calculated. 1-3 =SOC 原 -SOC1-SOC3=50%-18%-(100%-90%)=22%.

[0105] So the next time SOC-OCV correction occurs, i.e., SOC... 原 When it is 50%, the corrected SOC1 = 28% (50% - 22% = 28%).

[0106] like Figure 4 As shown, in one embodiment of the electric vehicle SOC-OCV correction method of the present invention, step S3 further includes:

[0107] Step S35: If the OCV correction flag is not 1, exit the correction mode.

[0108] The electric vehicle SOC-OCV correction method provided in this embodiment of the invention stores the ΔSOC1 value that needs to be corrected after an SOC-OCV correction occurs, and performs online correction on the ΔSOC1 value during subsequent discharge or charging processes to prevent incorrect correction of the current SOC in the next instance. 原 It can eliminate the difference between the calibrated SOC-OCV parameters and the current SOC-OCV parameters of the battery pack; SOC-OCV correction can only be performed after the actual SOC-OCV parameter values ​​of the battery pack are confirmed online, which can effectively avoid incorrect SOC-OCV correction.

[0109] The embodiments of this disclosure have now been described in detail. To avoid obscuring the concept of this disclosure, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.

[0110] While specific embodiments of this disclosure have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of this disclosure. The scope of this disclosure is defined by the appended claims.

Claims

1. A method for correcting the state of charge (SOC) of an electric vehicle to an open-circuit vehicle (OCV), characterized in that, include: Perform SOC-OCV correction on the power battery, and after SOC-OCV correction, store the △SOC1 value that needs to be corrected; During the discharge process, the value of ΔSOC1 is corrected based on the capacity discharged by the battery pack after the SOC reaches 0%. During the charging process, the value of ΔSOC1 is corrected according to the magnitude of the SOC jump. The process of performing SOC-OCV correction on the power battery and storing the ΔSOC1 value to be corrected after SOC-OCV correction specifically includes: After the vehicle controller is activated, it is determined whether the battery resting time is greater than the preset resting time threshold. If so, the SOC1 value corresponding to the current lowest single cell voltage and the current lowest cell temperature is obtained by linear interpolation in the pre-calibrated MAP table. The MAP table is used to characterize the relationship between the lowest single cell voltage, the lowest cell temperature and the SOC1 value. Determine whether the SOC1 value corresponding to the current lowest single cell voltage and the current lowest cell temperature is less than the first preset SOC threshold; If so, then determine SOC. 原 - Is SOC1 greater than the first preset amplitude, where SOC 原 Used to indicate the SOC value of the battery in real time before it is left to stand; If so, then by using the formula △SOC1=SOC 原 -SOC1, calculate the required correction value of △SOC1, and store the required correction value of △SOC1. During the discharge process, the value of ΔSOC1 is corrected based on the capacity discharged by the battery pack after the SOC reaches 0%, specifically including: In discharge mode, determine whether the OCV correction flag is 1; If so, then determine SOC. 原 Is it less than or equal to the second preset SOC threshold? If so, determine whether the battery pack can discharge to the minimum single cell voltage to reach the preset voltage threshold after the SOC is 0%. If so, record the discharge capacity of the battery from 0% SOC to the point where the lowest single cell voltage reaches the preset voltage threshold. Based on discharge capacity, rated capacity, and battery health, the formula SOC2 = A1 / (C) is used. 额定 *SOH) calculates SOC2, where SOC2 represents the true SOC when SOC is displayed as 0%, A1 represents the discharge capacity, and C 额定 The rated capacity is indicated by SOH, and the battery health status is indicated by SOH. Using the formula △SOC 1-1 =SOC 原 -SOC1-SOC2, calculate the correction result of △SOC1 value; If SOC 原 If the value is not less than or equal to the second preset SOC threshold, then during the discharge process, based on the discharge current, discharge time, and battery pack voltage difference, it is determined whether the ΔSOC1 value needs to be corrected. During the charging process, the value of ΔSOC1 is corrected according to the amplitude of the SOC jump, specifically including: In charging mode, check if the OCV correction flag is 1; If so, can the battery be charged to 99% SOC? If the battery can be charged to 99% SOC, then adjust the SOC to 100%. If the battery cannot be charged to 99% SOC, then the formula ΔSOC3 = 100% - SOC can be used. 跳变 Calculate the SOC jump amplitude ΔSOC3 before reaching full charge, where SOC 跳变 This represents the SOC value before jumping to 100%; Using the formula △SOC 1-3 =SOC 原 -SOC1-△SOC3, calculate the corrected value of △SOC1.

2. The correction method for electric vehicle SOC-OCV according to claim 1, characterized in that, The preset resting time threshold is 0.75h-1.5h, the first preset SOC threshold is 13%-20%, and the first preset amplitude is 3%-6%.

3. The correction method for electric vehicle SOC-OCV according to claim 1, characterized in that, The step of performing SOC-OCV correction on the power battery and storing the ΔSOC1 value to be corrected after SOC-OCV correction also includes: If the battery resting time is not greater than the preset resting time threshold, or the SOC1 value corresponding to the current lowest single cell voltage and the current lowest battery temperature is not less than the first preset SOC threshold, or SOC 原 If SOC1 is not greater than the first preset amplitude, exit correction mode.

4. The correction method for electric vehicle SOC-OCV according to claim 1, characterized in that, The second preset SOC threshold is 25%-35%, and the preset voltage threshold is 2.1V-2.5V.

5. The correction method for electric vehicle SOC-OCV according to claim 1, characterized in that, The method of correcting the ΔSOC1 value based on the capacity discharged by the battery pack after reaching 0% SOC during the discharge process also includes: If the OCV correction flag is not 1, or if the battery pack cannot discharge to the minimum single cell voltage to reach the preset voltage threshold after the SOC is 0%, then exit the correction mode.

6. The correction method for electric vehicle SOC-OCV according to claim 1, characterized in that, The method of correcting the ΔSOC1 value based on the SOC jump amplitude during charging also includes: If the OCV correction flag is not 1, exit correction mode.

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