A battery cluster soc estimation method

Abstract

The present application relates to the technical field of battery SOC estimation, and discloses a battery cluster SOC estimation method, which calibrates the rated capacity of the battery cluster through capacity calibration, guarantees that the BMS system can obtain the actual capacity of the battery cluster and optimizes the precision error of SOC caused by battery aging, calibrates SOC through battery cluster static OCV-SOC, avoids the fact that the specific size of self-consumption power cannot be predicted in the case that the battery cluster is not used for a long time, obtains the static calibration SOC according to the open-circuit voltage state of the battery cell, and calibrates the consumed power back in the charging and discharging process, so that the SOC does not change in the static state, thereby accurately realizing the estimation of the SOC of the battery cluster and avoiding the influence on customer use.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery SOC estimation, and particularly relates to a battery cluster SOC estimation method. BACKGROUND

[0002] SOC (State of Charge) refers to the ratio of the current remaining capacity of the battery to its rated capacity. As a core component of the BMS (Battery Monitoring and Management System), SOC is not only a key element of the energy storage system, but also a decisive indicator to ensure the stable operation of the energy storage power station. It plays a crucial role in improving the service life of the battery and ensuring the safety of use.

[0003] However, as a key parameter inside the battery, the direct and accurate measurement of SOC is difficult to achieve, and can only rely on various estimation methods for approximate calculation.

[0004] Currently, the industry generally adopts a method combining the ampere-hour integration method and the open-circuit voltage method to estimate SOC. Among them, the ampere-hour integration method is prone to errors in the current measurement link due to the limitations of sampling accuracy and sampling interval. These errors will continue to accumulate over time, resulting in inaccurate SOC estimation results. In addition, as the use time of the battery increases, the aging of the battery will cause its capacity to gradually decrease and its internal resistance to continuously increase, making the SOC estimation process more complex and challenging.

[0005] Therefore, in view of the problems existing in the prior art, it is necessary to conduct in-depth research and improvement.

[0006] The above information is given as background information only to assist with understanding the present disclosure, and does not determine or acknowledge whether any of the above is available as prior art with respect to the present disclosure. SUMMARY

[0007] The present application provides a battery cluster SOC estimation method to solve the problems in the prior art.

[0008] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0009] In a first aspect, the present application provides a battery cluster SOC estimation method, which comprises:

[0010] S1, calibrating the rated capacity of the battery cluster;

[0011] S2, judging whether the battery cluster is in a static state; if yes, executing S3, and if no, executing S4;

[0012] S3, obtaining the average single cell voltage and the static display SOC of the battery cluster, and searching the set OCV-SOC data table to find the calibration SOC corresponding to the average single cell voltage of the battery cluster, and correcting the static display SOC of the battery cluster to the found calibration SOC;

[0013] S4, judging whether the battery cluster is in a charging state; if yes, executing S5, and if no, executing S12;

[0014] S5, when the battery cluster is in a charging state, judging whether the calibration SOC of the battery cluster is greater than or equal to the static display SOC of the battery cluster; the calibration SOC of the battery cluster is determined by searching in the OCV-SOC data table when the battery cluster is in a static state; if yes, executing S6, and if no, executing S9;

[0015] S6, judging whether the difference between the real-time SOC of the battery cluster and the static display SOC of the battery cluster is less than or equal to ∆SOC difference*2; the ∆SOC difference at this time = the calibration SOC of the battery cluster - the static display SOC of the battery cluster; if yes, executing S7, and if no, executing S8;

[0016] S7, calculating the calibrated SOC of the battery cluster according to the following formula:

[0017] the calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster*2);

[0018] S8, calculating the calibrated SOC of the battery cluster according to the following formula:

[0019] the calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster;

[0020] S9, judging whether the difference between the real-time SOC of the battery cluster and the static display SOC of the battery cluster is less than or equal to ∆SOC difference; the ∆SOC difference at this time = the static display SOC of the battery cluster - the calibration SOC of the battery cluster; if yes, executing S10, and if no, executing S11;

[0021] S10, calculating the calibrated SOC of the battery cluster according to the following formula:

[0022] the calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster*0.5);

[0023] S11, calculating the calibrated SOC of the battery cluster according to the following formula:

[0024] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster;

[0025] S12, determine that the battery cluster is in a discharging state, when the battery cluster is in the discharging state, determine whether the calibrated SOC of the battery cluster is greater than or equal to the static display SOC of the battery cluster; the calibrated SOC of the battery cluster is determined by looking up in an OCV-SOC data table when the battery cluster is in a static state; if yes, perform S13, if not, perform S16;

[0026] S13, determine whether the difference between the static display SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to the ∆SOC difference value; the ∆SOC difference value at this time = the calibrated SOC of the battery cluster - the static display SOC of the battery cluster; if yes, perform S14, if not, perform S15;

[0027] S14, calculate the calibrated SOC of the battery cluster according to the following formula:

[0028] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 0.5);

[0029] S15, calculate the calibrated SOC of the battery cluster according to the following formula:

[0030] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster;

[0031] S16, determine whether the difference between the static display SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to the ∆SOC difference value * 2; the ∆SOC difference value at this time = the static display SOC of the battery cluster - the calibrated SOC of the battery cluster; if yes, perform S17, if not, perform S18;

[0032] S17, calculate the calibrated SOC of the battery cluster according to the following formula:

[0033] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 2);

[0034] S18, calculate the calibrated SOC of the battery cluster according to the following formula:

[0035] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster.

[0036] Further, in the battery cluster SOC estimation method, the S1 comprises:

[0037] S101, record the accumulated charge capacity at the charge stop time and the accumulated discharge capacity at the charge stop time of the battery cluster after the battery cluster is fully charged;

[0038] S102, record the accumulated charge capacity at the discharge stop time and the accumulated discharge capacity at the discharge stop time of the battery cluster after the battery cluster is fully discharged within a second set time;

[0039] S103, calculate the actual capacity of the battery cluster according to the accumulated charge capacity at the charge stop time, the accumulated discharge capacity at the charge stop time, the accumulated charge capacity at the discharge stop time and the accumulated discharge capacity at the discharge stop time, and correct the rated capacity of the battery cluster to the calculated actual capacity, thereby completing the calibration of the rated capacity of the battery cluster.

[0040] Further, in the battery cluster SOC estimation method, the calculation formula of the actual capacity of the battery cluster is:

[0041] The actual capacity of the battery cluster = (the accumulated discharge capacity at the discharge stop time - the accumulated discharge capacity at the charge stop time) - (the accumulated charge capacity at the discharge stop time - the accumulated charge capacity at the charge stop time).

[0042] Further, in the battery cluster SOC estimation method, before the S3, the method further comprises:

[0043] S2.5, judge whether the standing time of the battery cluster is greater than a first set time; if yes, execute S3, if not, continue to execute S2.5.

[0044] Further, in the battery cluster SOC estimation method, the S3 is specifically:

[0045] Obtain the average single cell voltage and the standing display SOC of the battery cluster, and find the calibration SOC corresponding to the average single cell voltage of the battery cluster from the set OCV-SOC data table through bisection method, and correct the standing display SOC of the battery cluster to the found calibration SOC.

[0046] Further, in the battery cluster SOC estimation method, the calculation formula of the real-time SOC of the battery cluster is:

[0047] The real-time SOC of the battery cluster = (the remaining capacity of the battery cluster ÷ the actual capacity of the battery cluster) * 100%.

[0048] Further, in the battery cluster SOC estimation method, the method further comprises:

[0049] S21, during the charging process of the battery cluster, when the real-time SOC of the battery cluster is greater than 75%, obtain the maximum single cell voltage of the battery cluster and the real-time SOC of the battery cluster.

[0050] S22, find the dynamic calibration SOC of the battery cluster corresponding to the maximum single cell voltage of the battery cluster from the set OCV-SOC data table;

[0051] S23, determine whether the dynamic calibration SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if yes, execute S24, and if no, execute S27;

[0052] S24, determine whether the difference between the dynamic calibration SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if yes, execute S25, and if no, execute S26;

[0053] S25, calculate the calibrated SOC of the battery cluster according to the following formula:

[0054] Calibrated SOC of the battery cluster = remaining capacity of the battery cluster + (ampere-hour integrated quantity of the battery cluster * 2);

[0055] S26, calculate the calibrated SOC of the battery cluster according to the following formula:

[0056] Calibrated SOC of the battery cluster = remaining capacity of the battery cluster + (ampere-hour integrated quantity of the battery cluster * 4);

[0057] S27, determine whether the dynamic calibration SOC of the battery cluster is less than the real-time SOC of the battery cluster; if yes, execute S28, and if no, execute S211;

[0058] S28, determine whether the difference between the real-time SOC of the battery cluster and the dynamic calibration SOC of the battery cluster is less than or equal to 5; if yes, execute S29, and if no, execute S210;

[0059] S29, calculate the calibrated SOC of the battery cluster according to the following formula:

[0060] Calibrated SOC of the battery cluster = remaining capacity of the battery cluster + (ampere-hour integrated quantity of the battery cluster * 0.5);

[0061] S210, calculate the calibrated SOC of the battery cluster according to the following formula:

[0062] Calibrated SOC of the battery cluster = remaining capacity of the battery cluster + (ampere-hour integrated quantity of the battery cluster * 0.25);

[0063] S211, determine that the dynamic calibration SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and calculate the calibrated SOC of the battery cluster according to the following formula:

[0064] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster.

[0065] Further, in the battery cluster SOC estimation method, the method further comprises:

[0066] S31, during discharging of the battery cluster, when real-time SOC of the battery cluster is less than 25%, obtaining minimum single cell voltage of the battery cluster and real-time SOC of the battery cluster;

[0067] S32, searching for dynamic calibration SOC of the battery cluster corresponding to the minimum single cell voltage of the battery cluster from a set OCV-SOC data table;

[0068] S33, judging whether the dynamic calibration SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if yes, performing S34, and if no, performing S37;

[0069] S34, judging whether the difference between the dynamic calibration SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if yes, performing S35, and if no, performing S36;

[0070] S35, calculating the calibrated SOC of the battery cluster according to the following formula:

[0071] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 0.5);

[0072] S36, calculating the calibrated SOC of the battery cluster according to the following formula:

[0073] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 0.25);

[0074] S37, judging whether the dynamic calibration SOC of the battery cluster is less than the real-time SOC of the battery cluster; if yes, performing S38, and if no, performing S311;

[0075] S38, judging whether the difference between the real-time SOC of the battery cluster and the dynamic calibration SOC of the battery cluster is less than or equal to 5; if yes, performing S39, and if no, performing S310;

[0076] S39, calculating the calibrated SOC of the battery cluster according to the following formula:

[0077] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 2);

[0078] S310, calculate the calibrated SOC of the battery cluster according to the following formula:

[0079] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 4);

[0080] S311, determine that the dynamic calibrated SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and calculate the calibrated SOC of the battery cluster according to the following formula:

[0081] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster.

[0082] In a second aspect, the present application provides a computer device, comprising a memory and a processor, the memory stores a computer program, and the processor implements the battery cluster SOC estimation method provided in the first aspect when executing the computer program.

[0083] In a third aspect, the present application provides a computer readable storage medium, which stores computer executable instructions, and the computer executable instructions are executed by a computer processor to implement the battery cluster SOC estimation method provided in the first aspect.

[0084] Compared with the prior art, the present application has the following beneficial effects:

[0085] The battery cluster SOC estimation method provided by the present application first calibrates the rated capacity of the battery cluster through capacity calibration, ensures that the BMS system can obtain the actual capacity of the battery cluster and optimizes the precision error of the SOC caused by battery aging, then calibrates the SOC through the battery cluster static OCV-SOC, avoids the fact that the specific size of the self-consumption power cannot be predicted in the case that the battery cluster is not used for a long time, obtains the static calibration SOC according to the open-circuit voltage state of the battery cell, and calibrates the consumed power back in the charging and discharging process, so as to ensure that the SOC does not change in the static state, thereby accurately realizing the estimation of the SOC of the battery cluster and avoiding the influence on the use of customers.

[0086] The present application has other characteristics and advantages, which will be apparent or will be described in detail in the accompanying drawings and subsequent specific embodiments incorporated herein, which together serve to explain the specific principles of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0087] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0088] Figure 1 is a flowchart of a battery cluster SOC estimation method provided by an embodiment of the present application;

[0089] Figure 2 is a flowchart of a battery cluster SOC estimation method provided by an embodiment of the present application;

[0090] Figure 3 is a detailed flowchart of S1 mentioned by an embodiment of the present application;

[0091] Figure 4 is a structural schematic diagram of a computer device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0092] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0093] In this paper, the term "embodiment" means that the specific features, structures or characteristics described in combination with the embodiment can be included in at least one embodiment of the present application. The term "embodiment" appearing at various positions in the specification does not necessarily refer to the same embodiment, and does not particularly limit the independence or association between other embodiments. In principle, in this application, as long as there is no technical contradiction or conflict, each technical feature mentioned in each embodiment can be combined in any way to form a corresponding implementable technical solution.

[0094] Unless otherwise defined, the meanings of the technical terms used in this paper are the same as those commonly understood by those skilled in the art to which the present application belongs; the use of related terms in this paper is only for the purpose of describing specific embodiments, and is not intended to limit the present application.

[0095] In the description of the present application, the word "and / or" is a description of the logical relationship between the objects, which means that there can be three relationships, for example, A and / or B, which means that there are three cases: A exists, B exists, and A and B exist at the same time. In addition, the character " / " in this paper generally represents that the associated objects before and after are a "or" logical relationship.

[0096] In the present application, the terms such as "first" and "second" are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual number, primary or secondary, or order relationship between the entities or operations.

[0097] In the present application, the "includes", "contains", "has", or other similar expressions used in the statements are intended to cover non-exclusive inclusion, and the expressions do not exclude the presence of additional elements in the process, method or product including the elements, so that the process, method or product including a series of elements can not only include those defined elements, but also include other elements not explicitly listed, or also include elements inherent to such process, method or product.

[0098] In the present application, the expressions such as "greater than", "less than", "exceed" are understood as not including the number; the expressions such as "above", "below", "within" are understood as including the number. In addition, in the description of the embodiments of the present application, the meaning of "multiple" is more than two (including two), and similar expressions related to "multiple" are also understood in this way, for example, "multiple groups", "multiple times", etc., unless otherwise explicitly specified.

[0099] In the description of the embodiments of the present application, the spatial-related expressions used, such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "vertical", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. The indicated orientation or position relationship is based on the orientation or position relationship shown in the specific embodiment or the drawing, and is only for the convenience of describing the specific embodiments of the present application or for the reader to understand, and does not indicate or imply that the indicated device or component must have a specific position, a specific orientation, or be constructed or operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0100] Unless otherwise explicitly specified or limited, in the description of the embodiments of the present application, the terms "mount", "connect", "connect", "fix", "set", etc. should be understood broadly. For example, the "connection" can be a fixed connection, or a detachable connection, or an integral setting; it can be a mechanical connection, or an electrical connection, or a communication connection; it can be directly connected, or indirectly connected through an intermediate medium; it can be the internal communication or interaction relationship of two elements. For those skilled in the art to which the present application belongs, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0101] Embodiment one

[0102] In view of the defects in the prior art, the applicant, based on years of rich practical experience and professional knowledge in this field, and with the use of theory, actively researches and innovates to create a technology that can solve the defects in the prior art. After continuous research, design, and repeated trial samples and improvements, the present invention is finally created, which has practical value.

[0103] Please refer to Figures 1-2 The embodiment one of the present application provides a flowchart of a battery cluster SOC estimation method, which is suitable for the scene of estimating the SOC of a battery cluster. The method specifically includes the following steps:

[0104] S1, calibrate the rated capacity of the battery cluster.

[0105] It should be noted that this step is to ensure the accuracy of the rated capacity data of the battery cluster, because the actual capacity of the battery will change due to factors such as aging and temperature change during use. By calibration, the rated capacity data in the BMS (Battery Management System) can be updated, providing a basis for subsequent SOC estimation.

[0106] S2, determine whether the battery cluster is in a stationary state; if yes, execute S3, if not, execute S4.

[0107] It should be noted that the stationary state means that the battery cluster is not charging or discharging, and is in a stationary state. This step is to determine whether the OCV (Open Circuit Voltage) method can be used for SOC estimation, because the OCV method is most accurate after the battery is stationary for a period of time.

[0108] S3, obtain the average cell voltage and stationary display SOC of the battery cluster, and find the calibration SOC corresponding to the average cell voltage of the battery cluster from the set OCV-SOC data table, and correct the stationary display SOC of the battery cluster to the found calibration SOC.

[0109] It should be noted that when the battery cluster is in a stationary state, the voltage of each battery cell in the battery cluster is measured to calculate the average cell voltage. Then, according to the voltage value, the corresponding calibration SOC is found in the pre-set OCV-SOC data table. This calibration SOC will be used to correct the stationary display SOC of the battery cluster to improve accuracy.

[0110] S4, determine whether the battery cluster is in a charging state; if yes, execute S5, if not, execute S12.

[0111] It should be noted that if the battery cluster is not in a static state, it means that it is in a charging or discharging state, and this step is to distinguish whether the battery cluster is in a charging or discharging state, so as to take different SOC estimation strategies.

[0112] S5, when the battery cluster is in a charging state, judging whether the calibrated SOC of the battery cluster is greater than or equal to the static display SOC of the battery cluster; the calibrated SOC of the battery cluster is determined by looking up in the OCV-SOC data table when the battery cluster is in a static state; if yes, S6 is executed, if no, S9 is executed.

[0113] It should be noted that this step is to judge the relationship between the calibrated SOC and the static display SOC to determine whether further calibration is needed.

[0114] S6, judging whether the difference between the real-time SOC of the battery cluster and the static display SOC of the battery cluster is less than or equal to ∆SOC difference*2; at this time, ∆SOC difference = the calibrated SOC of the battery cluster - the static display SOC of the battery cluster; if yes, S7 is executed, if no, S8 is executed.

[0115] S7, calculating the calibrated SOC of the battery cluster according to the following formula:

[0116] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster*2).

[0117] S8, calculating the calibrated SOC of the battery cluster according to the following formula:

[0118] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster.

[0119] It should be noted that in S6-S8, for the case that the battery cluster is in a charging state, if the calibrated SOC is greater than or equal to the static display SOC, and the difference between the real-time SOC and the static display SOC is within a certain range (∆SOC difference*2), the enhanced ampere-hour integration method (multiplied by 2) is adopted for SOC calibration to reflect the SOC change in the charging process more quickly.

[0120] S9, judging whether the difference between the real-time SOC of the battery cluster and the static display SOC of the battery cluster is less than or equal to ∆SOC difference; at this time, ∆SOC difference = the static display SOC of the battery cluster - the calibrated SOC of the battery cluster; if yes, S10 is executed, if no, S11 is executed.

[0121] S10, calculating the calibrated SOC of the battery cluster according to the following formula:

[0122] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 0.5).

[0123] S11, the calibrated SOC of the battery cluster is calculated according to the following formula:

[0124] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster.

[0125] It should be noted that in S9-S11, for the case that the battery cluster is in a charging state, if the calibrated SOC is less than the static display SOC, or the difference between the real-time SOC and the static display SOC exceeds a certain range, the standard ampere-hour integration method is used for SOC calibration.

[0126] S12, determine that the battery cluster is in a discharging state, and determine whether the calibrated SOC of the battery cluster is greater than or equal to the static display SOC of the battery cluster when the battery cluster is in a discharging state; the calibrated SOC of the battery cluster is determined by looking up in the OCV-SOC data table when the battery cluster is in a static state; if yes, execute S13, if no, execute S16.

[0127] S13, determine whether the difference between the static display SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to the ∆SOC difference value; the ∆SOC difference value at this time = the calibrated SOC of the battery cluster - the static display SOC of the battery cluster; if yes, execute S14, if no, execute S15.

[0128] S14, the calibrated SOC of the battery cluster is calculated according to the following formula:

[0129] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 0.5).

[0130] S15, the calibrated SOC of the battery cluster is calculated according to the following formula:

[0131] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster.

[0132] S16, determine whether the difference between the static display SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to the ∆SOC difference value * 2; the ∆SOC difference value at this time = the static display SOC of the battery cluster - the calibrated SOC of the battery cluster; if yes, execute S17, if no, execute S18.

[0133] S17, the calibrated SOC of the battery cluster is calculated according to the following formula:

[0134] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 2).

[0135] S18, calculate the calibrated SOC of the battery cluster according to the following formula:

[0136] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster.

[0137] It should be noted that in S12-S18, the logic is similar to the charging state, but the discharge condition is processed. It also includes judging the relationship between the calibrated SOC and the static display SOC, the difference between the real-time SOC and the static display SOC, and using the enhanced or standard ampere-hour integration method for SOC calibration.

[0138] Specifically, S12: determine that the battery cluster is in a discharge state.

[0139] S13-S15: If the calibrated SOC is greater than or equal to the static display SOC, and the difference between the static display SOC and the real-time SOC is within a certain range (ΔSOC difference), then the SOC is calibrated using the weakened ampere-hour integration method (multiplied by 0.5) to reflect the SOC change during discharge, but the calibration speed is slowed down to avoid over-calibration.

[0140] S16-S18: If the calibrated SOC is less than the static display SOC, or the difference between the static display SOC and the real-time SOC exceeds a certain range (ΔSOC difference * 2), then the SOC is calibrated using the standard ampere-hour integration method.

[0141] The battery cluster SOC estimation method of the embodiment of the application combines the OCV method and the ampere-hour integration method, and considers the static, charging and discharging states of the battery cluster, as well as the relationship between the calibrated SOC and the static display SOC, to realize accurate estimation of the SOC of the battery cluster. This method not only improves the accuracy of SOC estimation, but also enhances the reliability and stability of the battery management system.

[0142] Please refer to Figure 3 In one embodiment of the present embodiment, S1 is further refined into the following three specific steps to achieve more accurate capacity calibration:

[0143] S101, after the battery cluster is fully charged, record the accumulated charging capacity at the time of charging stop and the accumulated discharging capacity at the time of charging stop.

[0144] It is to be noted that, first, the battery cluster is subjected to full charging operation, i.e. it is charged to its maximum capacity. At the time when the charging stops, the accumulated charging capacity at that time (i.e. the total amount of electricity charged from the first charging to the present charging) and the accumulated discharging capacity at the time when the charging stops (i.e. the total amount of electricity discharged by the battery cluster before the present charging, for considering the historical usage of the battery) are recorded.

[0145] S102, after the battery cluster is subjected to full discharging operation for a second set time, the accumulated charging capacity at the time when the discharging stops and the accumulated discharging capacity at the time when the discharging stops are recorded.

[0146] It is to be noted that, immediately after, the battery cluster is subjected to full discharging operation for a second set time. This second set time is to ensure that the battery cluster has sufficient time to be fully discharged, while avoiding the damage to the battery caused by too long time of discharging, which can be eight hours for example.

[0147] At the time when the discharging stops, the accumulated charging capacity at that time (i.e. the total amount of electricity charged by the battery cluster before the present discharging, for considering the possible charging history) and the accumulated discharging capacity at the time when the discharging stops (i.e. the total amount of electricity discharged from the first discharging to the present discharging) are also recorded.

[0148] S103, the actual capacity of the battery cluster is calculated according to the accumulated charging capacity at the time when the charging stops, the accumulated discharging capacity at the time when the charging stops, the accumulated charging capacity at the time when the discharging stops and the accumulated discharging capacity at the time when the discharging stops, and the rated capacity of the battery cluster is corrected to the calculated actual capacity, thereby completing the calibration of the rated capacity of the battery cluster.

[0149] It is to be noted that, by using the accumulated charging capacity and the accumulated discharging capacity recorded in the steps S101 and S102, the actual capacity of the battery cluster is calculated by a specific calculation method.

[0150] This actual capacity reflects the real energy storage capability of the battery cluster in the current state.

[0151] Finally, the rated capacity of the battery cluster is corrected to the calculated actual capacity, thereby completing the calibration of the rated capacity of the battery cluster.

[0152] In one embodiment of the present embodiment, the calculation formula of the actual capacity of the battery cluster is as follows:

[0153] The actual capacity of the battery cluster = (the accumulated discharging capacity at the time when the discharging stops - the accumulated discharging capacity at the time when the charging stops) - (the accumulated charging capacity at the time when the discharging stops - the accumulated charging capacity at the time when the charging stops).

[0154] It is to be noted that this formula is derived based on the principle of energy conservation of the battery and the change of electricity in the charging and discharging process.

[0155] Substitute the four values recorded above into the formula, the actual capacity of the battery cluster can be obtained. This value reflects the true energy storage capability of the battery cluster in the current state, and is an important basis for subsequent SOC estimation.

[0156] It should be noted that this formula assumes that there are no other energy losses (such as battery self-discharge, heat loss, etc.) during charging and discharging, or that these losses have been taken into account. In actual application, the formula may need to be modified or adjusted according to specific circumstances.

[0157] In addition, this formula also emphasizes the need to accurately record the charging and discharging history of the battery cluster when calibrating the capacity, to ensure the accuracy of the calculation. This usually needs to be realized through the BMS (Battery Management System), which can monitor and record the charging and discharging state of the battery cluster in real time.

[0158] In one embodiment of the present embodiment, before S3, the method further comprises:

[0159] S2.5 judges whether the resting time of the battery cluster is greater than the first set time; if yes, S3 is executed, if not, S2.5 is continued.

[0160] It should be noted that this first set time is a threshold value, which is used to ensure that the battery cluster has been in a resting state for a long enough time, so that its open circuit voltage can be stable and accurately reflect the SOC of the battery.

[0161] The OCV method relies on the open circuit voltage of the battery cluster in the resting state to estimate the SOC. If the resting time of the battery cluster is not long enough, the open circuit voltage may not be stable, resulting in inaccurate SOC estimation. By adding S2.5 step, it can be ensured that the battery cluster has been in a stable state before executing the OCV method.

[0162] By ensuring the stability of the battery cluster in the resting state, the accuracy and reliability of the SOC estimation can be improved. This is very important for the performance of the battery management system and the long-term use of the battery cluster.

[0163] In summary, the S2.5 step is added to ensure that the battery cluster has been in a stable resting state before executing the OCV method, so as to improve the accuracy and reliability of the SOC estimation.

[0164] In one embodiment of the present embodiment, S3 is specifically:

[0165] The average single cell voltage and the static display SOC of the battery cluster are obtained, and the calibration SOC corresponding to the average single cell voltage of the battery cluster is found by bisection from the set OCV-SOC data table, and the static display SOC of the battery cluster is corrected to the found calibration SOC.

[0166] It should be noted that bisection is an efficient search algorithm that can quickly find the position of the target value in an ordered array.

[0167] The specific process of bisection search is as follows:

[0168] First, the minimum and maximum values of OCV in the OCV-SOC data table and the corresponding minimum and maximum values of SOC are determined.

[0169] Then, the intermediate OCV value and the corresponding intermediate SOC value are calculated.

[0170] Compare the average single cell voltage of the battery cluster with the intermediate OCV value:

[0171] If the average single cell voltage is less than the intermediate OCV value, continue searching in the left half of the data table;

[0172] If the average single cell voltage is greater than the intermediate OCV value, continue searching in the right half of the data table;

[0173] If the average single cell voltage is equal to (or very close to) the intermediate OCV value, the corresponding SOC value is found.

[0174] Repeat the above process until the OCV value closest to the average single cell voltage of the battery cluster and its corresponding SOC value are found.

[0175] In one embodiment of the embodiment, the real-time SOC of the battery cluster is calculated by ampere-hour integration, and the current integration is performed every 100 ms, and the specific calculation formula is:

[0176] The real-time SOC of the battery cluster = (the remaining capacity of the battery cluster ÷ the actual capacity of the battery cluster) * 100%.

[0177] It should be noted that in the embodiment, the real-time SOC of the battery cluster is calculated by ampere-hour integration. Ampere-hour integration is a commonly used battery SOC estimation method, which estimates the remaining capacity of the battery based on the current integration in the battery charging and discharging process, thereby obtaining the SOC value, providing reliable data support for the decision of the battery management system. At the same time, combined with the periodic capacity calibration and SOC correction steps, the accuracy and reliability of SOC estimation can be further improved.

[0178] To further improve the accuracy of SOC estimation, the embodiment of the present application also considers the calibration of the end SOC in the charging and discharging process, that is, when the real-time SOC of the battery cluster is greater than 75% or less than 25%, the dynamic calibration SOC of the battery cluster is confirmed by the maximum or minimum single cell voltage and the preset dynamic SOC-OCV data table, so that the real-time SOC of the battery cluster is accelerated or decelerated to chase the dynamic calibration SOC of the battery cluster, and the SOC error is reduced.

[0179] Specifically, in one implementation of the embodiment, for the case of charging the battery cluster, the method further comprises:

[0180] S21, during the charging process of the battery cluster, when the real-time SOC of the battery cluster is greater than 75%, the maximum single cell voltage of the battery cluster and the real-time SOC of the battery cluster are obtained.

[0181] S22, the dynamic calibration SOC of the battery cluster corresponding to the maximum single cell voltage of the battery cluster is found from the set OCV-SOC data table.

[0182] S23, it is judged whether the dynamic calibration SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if yes, S24 is executed, and if no, S27 is executed.

[0183] S24, it is judged whether the difference between the dynamic calibration SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if yes, S25 is executed, and if no, S26 is executed.

[0184] S25, the calibrated SOC of the battery cluster is calculated according to the following formula:

[0185] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 2).

[0186] S26, the calibrated SOC of the battery cluster is calculated according to the following formula:

[0187] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 4).

[0188] S27, it is judged whether the dynamic calibration SOC of the battery cluster is less than the real-time SOC of the battery cluster; if yes, S28 is executed, and if no, S211 is executed.

[0189] S28, it is judged whether the difference between the real-time SOC of the battery cluster and the dynamic calibration SOC of the battery cluster is less than or equal to 5; if yes, S29 is executed, and if no, S210 is executed.

[0190] S29, calculate the calibrated SOC of the battery cluster according to the following formula:

[0191] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 0.5).

[0192] S210, calculate the calibrated SOC of the battery cluster according to the following formula:

[0193] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 0.25).

[0194] S211, determine that the dynamic calibrated SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and calculate the calibrated SOC of the battery cluster according to the following formula:

[0195] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster.

[0196] It should be noted that this method compares the real-time SOC with the dynamic calibrated SOC obtained based on the maximum single cell voltage, and adjusts the calculation coefficient of the ampere-hour integrated quantity according to the difference, thereby realizing dynamic calibration of the SOC of the battery cluster. This method helps to further improve the accuracy of SOC estimation, especially in the terminal region of the charging process, helps to reduce the SOC error, and improves the performance of the battery management system and the long-term use reliability of the battery cluster.

[0197] In an embodiment of the present embodiment, for the discharging of the battery cluster, the method further comprises:

[0198] S31, during the discharging of the battery cluster, when the real-time SOC of the battery cluster is less than 25%, obtaining the minimum single cell voltage of the battery cluster and the real-time SOC of the battery cluster;

[0199] S32, searching for the dynamic calibrated SOC of the battery cluster corresponding to the minimum single cell voltage of the battery cluster from the set OCV-SOC data table;

[0200] S33, determining whether the dynamic calibrated SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if yes, performing S34, and if no, performing S37;

[0201] S34, determining whether the difference between the dynamic calibrated SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if yes, performing S35, and if no, performing S36;

[0202] S35, calculating the calibrated SOC of the battery cluster according to the following formula:

[0203] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 0.5);

[0204] S36, the calibrated SOC of the battery cluster is calculated according to the following formula:

[0205] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 0.25);

[0206] S37, it is judged whether the dynamic calibrated SOC of the battery cluster is less than the real-time SOC of the battery cluster; if yes, S38 is executed, and if no, S311 is executed;

[0207] S38, it is judged whether the difference between the real-time SOC of the battery cluster and the dynamic calibrated SOC of the battery cluster is less than or equal to 5; if yes, S39 is executed, and if no, S310 is executed;

[0208] S39, the calibrated SOC of the battery cluster is calculated according to the following formula:

[0209] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 2);

[0210] S310, the calibrated SOC of the battery cluster is calculated according to the following formula:

[0211] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + (the ampere-hour integrated quantity of the battery cluster * 4);

[0212] S311, it is determined that the dynamic calibrated SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and the calibrated SOC of the battery cluster is calculated according to the following formula:

[0213] The calibrated SOC of the battery cluster = the remaining capacity of the battery cluster + the ampere-hour integrated quantity of the battery cluster.

[0214] It should be noted that this method compares the real-time SOC with the dynamic calibrated SOC based on the minimum single cell voltage, and adjusts the calculation coefficient of the ampere-hour integrated quantity according to the difference, thereby realizing the dynamic calibration of the SOC of the battery cluster. This method helps to further improve the accuracy of SOC estimation, especially in the terminal region of the discharge process, helps to reduce the SOC error, and improves the performance of the battery management system and the long-term use reliability of the battery cluster.

[0215] Although the terms battery cluster, rated capacity, calibration, etc. are used more frequently in this application, the possibility of using other terms is not excluded. The use of these terms is merely to facilitate the description and explanation of the essence of the present application; any additional limitation is contrary to the spirit of the present application.

[0216] The battery cluster SOC estimation method provided by the embodiment of the present application firstly carries out a capacity calibration process to ensure that the rated capacity of the battery pack is accurately adjusted. This process is crucial for the battery management system (BMS) because it can help the BMS system to accurately obtain the actual capacity of the battery pack and further optimize the SOC estimation accuracy error caused by battery aging.

[0217] Next, the method adopts the relationship between the open circuit voltage OCV and the SOC under the static condition of the battery pack to calibrate the SOC. This step is particularly crucial because it can effectively deal with the problem that the self-consumption power of the battery pack is difficult to estimate after a long period of idling. Specifically, the method accurately obtains the calibration SOC value under the static condition according to the open circuit voltage state of the battery cell. In addition, the method also considers the power loss during the charging and discharging cycle of the battery and performs corresponding calibration compensation to ensure that the SOC value remains stable even under static conditions.

[0218] Finally, the SOC-OCV dynamic calibration SOC is performed at the end of the charging and discharging of the battery cluster, and the dynamic calibration SOC is obtained by looking up the preset dynamic SOC-OCV table according to the maximum or minimum single cell voltage of the battery cluster and the power of the battery cluster. The SOC of the battery cluster is calibrated to avoid the jump of the SOC of the battery cluster at the end of charging and discharging, and further improve the accuracy of the SOC estimation of the battery cluster.

[0219] This series of fine operations collectively ensures the high accuracy of the SOC estimation of the battery pack, thereby minimizing the inconvenience and impact on the customer's use caused by the deviation of the SOC estimation. In summary, the battery pack SOC estimation method provided by the present application not only improves the estimation accuracy, but also enhances the overall performance and reliability of the battery management system.

[0220] Embodiment two

[0221] Figure 4 A structural schematic diagram of a computer device is provided for the second embodiment of the present application. Figure 4 A block diagram of an exemplary computer device 12 suitable for implementing embodiments of the present application is shown. Figure 4 The computer device 12 shown is merely an example and should not impose any limitation on the function and scope of use of the embodiments of the present application.

[0222] As shown Figure 4 , computer device 12 is in the form of a general-purpose computing device. Components of computer device 12 can include, but are not limited to, one or more processors or processing units 16, a system memory 28, and a bus 18 that couples various system components including system memory 28 to processing unit 16.

[0223] Bus 18 represents one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, a graphics bus (e.g., an Accelerated Graphics Port, or AGP bus) and a local bus using any of a variety of bus architectures

[0224] Computer device 12 typically includes a variety of computer system readable media. Such media can be any available media that is accessible by computer device 12 and includes both

[0225] System memory 28 can include computer system readable media in the form of volatile memory, such as random access memory (RAM) 30 and / or cache memory 32. Computer device 12 can further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, storage system 34 can be provided for reading from and writing to a non-removable, non-volatile magnetic media (e.g., a "hard drive") Figure 4 (not shown) is typically provided as residual storage across computer device 12, and can be used for storing data that is less frequently accessed. Although exemplary computer device 12 is described as utilizing a magnetic media storage device, those skilled in the art will appreciate that other types of storage media, such as optical media like Blu-ray™ discs, DVD's, CD's, and the like, can also be used. It is to be appreciated that the storage media used in computer device 12 can be removable, non-removable, or a combination thereof. Figure 4 (not shown) is typically provided as residual storage across computer device 12, and can be used for storing data that is less frequently accessed. Although exemplary computer device 12 is described as utilizing a magnetic media storage device, those skilled in the art will appreciate that other types of storage media, such as optical media like Blu-ray™ discs, DVD's, CD's, and the like, can also be used. It is to be appreciated that the storage media used in computer device 12 can be removable, non-removable, or a combination thereof.

[0226] Program / utility 40 having a set (at least one) of program modules 42 can be stored in, for example, memory 28 by way of example, without limitation, operating system, one or more application programs, other program modules, and program data, each of which

[0227] Computer device 12 can also communicate with one or more external devices 14 such as a keyboard, a pointing device, a display 24, etc.; one or more devices that enable a user to interact with computer device 12; and / or any devices (e.g., network card, modem, etc.) that enable computer device 12 to communicate with one or more other computing devices. Such communication can occur via Input / Output (I / O) interface(s) 22. Still yet, computer device 12 can communicate with one or more networks, such as a local area network (LAN), a general wide area network (WAN), and / or a public network such as the Internet, via network adapter 20. As depicted, network adapter 20 communicates with the other components of computer device 12 via bus 18. It should be appreciated that although not shown, other hardware and / or software modules could be used in conjunction with computer device 12. Examples, include, but are not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data archival storage systems, etc. Figure 4

[0228] Processing unit 16 performs various function applications and data processing by running programs stored in system memory 28, such as implementing the battery cluster SOC estimation method provided by embodiments of the present application.

[0229] Embodiment Three

[0230] Embodiment Three of the present application provides a computer readable storage medium, having computer executable instructions stored thereon, which when executed by a processor implement the battery cluster SOC estimation method provided by all embodiments of the present application.

[0231] Any combination of one or more computer readable medium can be employed. The computer readable medium can be a computer readable signal medium or a computer readable storage medium. A computer readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer readable storage medium include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In this document, the computer readable storage medium can be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

[0232] ​A computer readable signal medium can include a propagated data signal with computer executable code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal can take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination thereof. A computer readable signal medium can be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate or transport programming code.

[0233] Program code embodied on a computer readable medium can be transmitted using any appropriate medium, including but not limited to wireless, wire line, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0234] Computer program code for carrying out operations of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0235] Finally, it should be noted that the technical solutions of the above embodiments have been described in the specification and drawings of the present application, but the patent protection scope of the present application should not be limited thereto. Any equivalent structure or equivalent flow replacement or modification based on the essential concept of the present application, using the content described in the specification and drawings of the present application, and directly or indirectly implementing the technical solutions of the above embodiments in other related technical fields, etc., are all included in the patent protection scope of the present application.

Claims

1. A method for estimating the state of charge (SOC) of a battery cluster, characterized in that, The method includes: S1. Calibrate the rated capacity of the battery cluster; S2. Determine whether the battery cluster is in a static state; if yes, proceed to S3; otherwise, proceed to S4. S3. Obtain the average cell voltage and static display SOC of the battery cluster, and find the calibration SOC corresponding to the average cell voltage of the battery cluster from the set OCV-SOC data table, and correct the static display SOC of the battery cluster to the found calibration SOC. S4. Determine whether the battery cluster is in a charging state; if yes, proceed to S5; if no, proceed to S12. S5. When the battery cluster is in a charging state, determine whether the calibration SOC of the battery cluster is greater than or equal to the static display SOC of the battery cluster; the calibration SOC of the battery cluster is determined by looking up in the OCV-SOC data table when the battery cluster is in a static state; if yes, proceed to S6; if no, proceed to S9. S6. Determine whether the difference between the real-time SOC of the battery cluster and the static display SOC of the battery cluster is less than or equal to ∆SOC difference * 2; at this time, ∆SOC difference = calibration SOC of the battery cluster - static display SOC of the battery cluster; if yes, then execute S7, otherwise execute S8. S7. Calculate the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2). S8. Calculate the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + the ampere-hour integral of the battery cluster; S9. Determine whether the difference between the real-time SOC of the battery cluster and the static display SOC of the battery cluster is less than or equal to the ∆SOC difference; at this time, the ∆SOC difference = the static display SOC of the battery cluster - the calibration SOC of the battery cluster; if yes, then execute S10, if no, then execute S11. S10. Calculate the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5). S11. Calculate the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + the ampere-hour integral of the battery cluster; S12. Determine that the battery cluster is in a discharging state. When the battery cluster is in a discharging state, determine whether the calibration SOC of the battery cluster is greater than or equal to the static display SOC of the battery cluster. The calibration SOC of the battery cluster is determined by looking up the OCV-SOC data table when the battery cluster is in a static state. If yes, proceed to S13; otherwise, proceed to S16. S13. Determine whether the difference between the static display SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to the ∆SOC difference; at this time, the ∆SOC difference = the calibration SOC of the battery cluster - the static display SOC of the battery cluster; if yes, then execute S14; if no, then execute S15. S14. Calculate the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5). S15. Calculate the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + the ampere-hour integral of the battery cluster; S16. Determine whether the difference between the static display SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to ∆SOC difference * 2; at this time, ∆SOC difference = static display SOC of the battery cluster - calibration SOC of the battery cluster; if yes, then execute S17, if no, then execute S18. S17. Calculate the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2). S18. Calculate the calibrated SOC of the battery cluster according to the following formula: The SOC of the calibrated battery cluster = the remaining capacity of the battery cluster + the ampere-hour integral of the battery cluster.

2. The battery cluster SOC estimation method according to claim 1, characterized in that, S1 includes: S101. After fully charging the battery cluster, record the cumulative charging capacity and cumulative discharging capacity of the battery cluster when charging stops. S102. After the battery cluster is fully discharged within a second set time, record the cumulative charging capacity and the cumulative discharging capacity of the battery cluster when the discharge stops. S103. Calculate the actual capacity of the battery cluster based on the cumulative charging capacity when charging stops, the cumulative discharging capacity when charging stops, the cumulative charging capacity when discharging stops, and the cumulative discharging capacity when discharging stops, and correct the rated capacity of the battery cluster to the calculated actual capacity, thereby completing the calibration of the rated capacity of the battery cluster.

3. The battery cluster SOC estimation method according to claim 2, characterized in that, The formula for calculating the actual capacity of the battery cluster is: The actual capacity of the battery cluster = (cumulative discharge capacity when discharge stops - cumulative discharge capacity when charging stops) - (cumulative charging capacity when discharge stops - cumulative charging capacity when charging stops).

4. The battery cluster SOC estimation method according to claim 1, characterized in that, Prior to S3, the method further includes: S2.5 Determine whether the resting time of the battery cluster is greater than the first set time; if yes, then execute S3; if no, then continue to execute S2.

5.

5. The battery cluster SOC estimation method according to claim 1, characterized in that, Specifically, S3 is: The average cell voltage and static displayed SOC of the battery cluster are obtained, and the calibration SOC corresponding to the average cell voltage of the battery cluster is found from the set OCV-SOC data table by binary search. The static displayed SOC of the battery cluster is then corrected to the found calibration SOC.

6. The battery cluster SOC estimation method according to claim 1, characterized in that, The formula for calculating the real-time SOC of the battery cluster is as follows: The real-time SOC of the battery cluster = (remaining capacity of the battery cluster ÷ actual capacity of the battery cluster) * 100%.

7. The battery cluster SOC estimation method according to claim 1, characterized in that, The method further includes: S21. During the charging process of the battery cluster, when the real-time SOC of the battery cluster is greater than 75%, the maximum single-cell voltage of the battery cluster and the real-time SOC of the battery cluster are obtained. S22. Find the dynamic calibration SOC of the battery cluster corresponding to the maximum single cell voltage of the battery cluster from the set OCV-SOC data table; S23. Determine whether the dynamic calibration SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if yes, proceed to S24; if no, proceed to S27. S24. Determine whether the difference between the dynamic calibration SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if yes, proceed to S25; if no, proceed to S26. S25. Calculate the calibrated SOC of the battery cluster according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2). S26. Calculate the calibrated SOC of the battery cluster according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 4). S27. Determine whether the dynamic calibration SOC of the battery cluster is less than the real-time SOC of the battery cluster; if yes, proceed to S28; if no, proceed to S211. S28. Determine whether the difference between the real-time SOC of the battery cluster and the dynamic calibration SOC of the battery cluster is less than or equal to 5; if yes, proceed to S29; if no, proceed to S210. S29. Calculate the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5). S210. Calculate the calibrated SOC of the battery cluster according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.25). S211. Determine that the dynamic calibration SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and calculate the calibrated SOC of the battery cluster according to the following formula: The SOC of the calibrated battery cluster = the remaining capacity of the battery cluster + the ampere-hour integral of the battery cluster.

8. The battery cluster SOC estimation method according to claim 1, characterized in that, The method further includes: S31. During the discharge process of the battery cluster, when the real-time SOC of the battery cluster is less than 25%, the minimum single-cell voltage of the battery cluster and the real-time SOC of the battery cluster are obtained. S32. Find the dynamic calibration SOC of the battery cluster corresponding to the minimum single cell voltage of the battery cluster from the set OCV-SOC data table; S33. Determine whether the dynamic calibration SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if yes, then execute S34; if no, then execute S37. S34. Determine whether the difference between the dynamic calibration SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if yes, proceed to S35; if no, proceed to S36. S35. Calculate the calibrated SOC of the battery cluster according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5). S36. Calculate the calibrated SOC of the battery cluster according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.25). S37. Determine whether the dynamic calibration SOC of the battery cluster is less than the real-time SOC of the battery cluster; if yes, execute S38; if no, execute S311. S38. Determine whether the difference between the real-time SOC of the battery cluster and the dynamic calibration SOC of the battery cluster is less than or equal to 5; if yes, proceed to S39; if no, proceed to S310. S39. Calculate the calibrated SOC of the battery cluster according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2). S310. Calculate the calibrated SOC of the battery cluster according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 4). S311. Determine that the dynamic calibration SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and calculate the calibrated SOC of the battery cluster according to the following formula: The SOC of the calibrated battery cluster = the remaining capacity of the battery cluster + the ampere-hour integral of the battery cluster.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the battery cluster SOC estimation method as described in any one of claims 1-8.

10. A computer-readable storage medium having computer-executable instructions stored thereon, characterized in that, The computer-executable instructions are executed by a computer processor to implement the battery cluster SOC estimation method as described in any one of claims 1-8.

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