Lithium iron phosphate battery SOC correction method, apparatus and device, storage medium and computer program product

Abstract

The invention relates to the technical field of battery application, in particular to a lithium iron phosphate battery SOC correction method and device, equipment, a storage medium and a computer program product. The method comprises the following steps: determining SOC variation according to voltage data and current data of a to-be-processed battery cell; determining an SOC estimated value according to the SOC variation and the initial SOC value; if the to-be-processed cell is in the plateau period, performing interpolation calculation through a preset open-circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value; and determining a target SOC value according to the SOC estimation value, the first correction value and the second correction value. According to the method, the SOC variation is determined according to the voltage data and the current data, the SOC estimation value is calculated by combining the initial SOC value, and finally the target SOC value is determined by integrating the SOC estimation value and the two correction values, so that the SOC estimation precision is improved.

Description

Technical Field

[0001] The present application relates to the field of battery application technology, and in particular to a method, device, equipment, storage medium and computer program product for correcting the SOC of a lithium iron phosphate battery. Background Art

[0002] With the rapid development of electric vehicles, energy storage systems and other fields, the demand for lithium iron phosphate (LiFePO4, LFP) batteries is growing. LFP batteries have become core components widely used in the new energy industry due to their high safety, long cycle life and stable working characteristics. However, the performance and life of the battery are closely related to the accuracy of its management system, among which the accurate estimation of the state of charge (SOC) is particularly critical. SOC reflects the remaining capacity of the battery and plays an important role in the charge and discharge control, safety protection and life management of the battery. At present, SOC estimation mainly relies on methods such as the ampere-hour integration method and the open circuit voltage (OCV) method. The ampere-hour integration method calculates the change in charge by accumulating the product of current and time, but this method is easily affected by current sensor drift and cumulative errors; while the OCV method estimates the relationship between open circuit voltage and SOC, but in the plateau period of LFP batteries (i.e., the SOC interval with a gentle voltage change), the relationship between OCV and SOC is not obvious, making it difficult for the OCV method to accurately estimate SOC at this stage. Therefore, how to improve the accuracy of SOC estimation of lithium iron phosphate batteries has become a technical problem that needs to be solved urgently. Summary of the invention

[0003] The main purpose of this application is to provide a lithium iron phosphate battery SOC correction method, device, equipment, storage medium and product, aiming to solve the technical problem of how to improve the SOC estimation accuracy of lithium iron phosphate batteries.

[0004] To achieve the above objectives, the present application provides a method for correcting SOC of a lithium iron phosphate battery, the method comprising:

[0005] Determine the SOC change according to the voltage data and current data of the battery cell to be processed;

[0006] Determining an estimated SOC value according to the SOC change and an initial SOC value;

[0007] If the battery cell to be processed is in a plateau period, interpolation calculation is performed through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value;

[0008] A target SOC value is determined according to the SOC estimated value, the first correction value, and the second correction value.

[0009] In one embodiment, before the step of performing interpolation calculation by using a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value if the battery cell to be processed is in a plateau period, the step further includes:

[0010] Determine the voltage change and current change of the battery cell to be processed according to the voltage data and the current data;

[0011] Acquiring temperature data of the battery cell to be processed, and determining temperature changes of the battery cell to be processed according to the temperature data;

[0012] Based on the voltage change, the current change and the temperature change, it is determined whether the battery cell to be processed is in the plateau period.

[0013] In one embodiment, if the battery cell to be processed is in a plateau period, the step of performing interpolation calculation through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value includes:

[0014] According to the current temperature of the battery cell to be processed, selecting the corresponding open circuit voltage mapping table in the preset open circuit voltage mapping table set as the first correction table;

[0015] Based on the first correction table, interpolate the SOC estimation value to obtain the first correction value;

[0016] According to the current temperature and the current charge and discharge rate of the battery cell to be processed, selecting a corresponding dynamic internal resistance mapping table in the preset dynamic internal resistance mapping table set as a second correction table;

[0017] Based on the second correction table, the SOC estimation value is interpolated to obtain the second correction value.

[0018] In one embodiment, the step of determining a target SOC value according to the SOC estimation value, the first correction value, and the second correction value includes:

[0019] Determining whether a difference between the SOC estimation value, the first correction value, and the second correction value exceeds a preset difference threshold;

[0020] If not, based on a first preset weight rule, the SOC estimation value, the first correction value and the second correction value are weighted and summed to obtain the target SOC value.

[0021] In one embodiment, before the step of determining the target SOC value according to the SOC estimated value, the first correction value and the second correction value, the method further includes:

[0022] If the battery cell to be processed is not in a plateau period, based on a second preset weight rule, the SOC estimation value, the first correction value and the second correction value are weighted and summed to obtain the target SOC value; wherein the weight corresponding to the SOC estimation value in the second preset weight rule is greater than the weight corresponding to the SOC estimation value in the first preset weight rule.

[0023] In one embodiment, after the step of determining the target SOC value according to the SOC estimated value, the first correction value and the second correction value, the method further includes:

[0024] Verifying the target SOC value based on a preset SOC range standard;

[0025] If the verification is successful, the current SOC state of the battery cell to be processed is updated based on the target SOC value.

[0026] In addition, to achieve the above-mentioned purpose, the present application also proposes a lithium iron phosphate battery SOC correction device, the lithium iron phosphate battery SOC correction device comprising:

[0027] A preliminary module, used to determine the SOC change according to the voltage data and current data of the battery cell to be processed;

[0028] An estimation module, configured to determine an estimated SOC value according to the SOC change and an initial SOC value;

[0029] A correction module, configured to obtain a first correction value and a second correction value by performing interpolation calculation through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set if the battery cell to be processed is in a plateau period;

[0030] A target module is used to determine a target SOC value according to the SOC estimation value, the first correction value and the second correction value.

[0031] In addition, to achieve the above-mentioned purpose, the present application also proposes a lithium iron phosphate battery SOC correction device, which includes: a memory, a processor, and a lithium iron phosphate battery SOC correction program stored in the memory and executable on the processor, and the lithium iron phosphate battery SOC correction program is configured to implement the steps of the lithium iron phosphate battery SOC correction method as described above.

[0032] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, on which a lithium iron phosphate battery SOC correction program is stored. When the lithium iron phosphate battery SOC correction program is executed by a processor, the steps of the lithium iron phosphate battery SOC correction method described above are implemented.

[0033] In addition, to achieve the above-mentioned purpose, the present application also proposes a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of the lithium iron phosphate battery SOC correction method as described above are implemented.

[0034] The present application determines the SOC change amount according to the voltage data and current data of the battery cell to be processed; determines the SOC estimation value according to the SOC change amount and the initial SOC value; if the battery cell to be processed is in a plateau period, interpolation calculation is performed through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value; and determines the target SOC value according to the SOC estimation value, the first correction value and the second correction value. The present application determines the SOC change amount according to the voltage data and the current data, and calculates the SOC estimation value in combination with the initial SOC value. In the plateau period, the open circuit voltage mapping table set and the dynamic internal resistance mapping table set are used for interpolation calculation to obtain the first and second correction values. Finally, the target SOC value is determined by combining the SOC estimation value and the two correction values. Through multiple data fusion and correction, the error caused by voltage stability in the plateau period is effectively compensated, and the accuracy and stability of SOC estimation are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a flow chart of the first embodiment of the SOC correction method for a lithium iron phosphate battery of the present application;

[0036] Figure 2 This is a schematic diagram of a sub-process in the second embodiment of the SOC correction method for a lithium iron phosphate battery of the present application;

[0037] Figure 3 This is a schematic diagram of a sub-process in the third embodiment of the SOC correction method for a lithium iron phosphate battery of the present application;

[0038] Figure 4 This is a schematic diagram of the module structure of the SOC correction device for a lithium iron phosphate battery according to an embodiment of the present application;

[0039] Figure 5 Schematic diagram of the device structure of the hardware operating environment involved in the lithium iron phosphate battery SOC correction method in the embodiment of the present application.

[0040] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0041] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0042] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0043] It should be noted that with the rapid development of electric vehicles, energy storage systems and other fields, the demand for lithium iron phosphate (LiFePO4, LFP) batteries is growing. LFP batteries have become core components widely used in the new energy industry due to their high safety, long cycle life and stable working characteristics. However, the performance and life of the battery are closely related to the accuracy of its management system, among which the accurate estimation of the state of charge (SOC) is particularly critical. SOC reflects the remaining capacity of the battery and plays an important role in the charge and discharge control, safety protection and life management of the battery. At present, SOC estimation mainly relies on methods such as the ampere-hour integration method and the open circuit voltage (OCV) method. The ampere-hour integration method calculates the change in power by accumulating the product of current and time, but this method is easily affected by current sensor drift and cumulative errors; while the OCV method estimates the relationship between open circuit voltage and SOC, but in the plateau period of LFP batteries (i.e., the SOC interval with a gentle voltage change), the relationship between OCV and SOC is not obvious, making it difficult for the OCV method to accurately estimate SOC at this stage. Therefore, how to improve the accuracy of SOC estimation of lithium iron phosphate batteries has become a technical problem that needs to be solved urgently.

[0044] The main solution of the present application is: determine the SOC change according to the voltage data and current data of the battery cell to be processed; determine the SOC estimation value according to the SOC change and the initial SOC value; if the battery cell to be processed is in a plateau period, interpolate the calculation through the preset open circuit voltage mapping table set and the preset dynamic internal resistance mapping table set to obtain the first correction value and the second correction value; determine the target SOC value according to the SOC estimation value, the first correction value and the second correction value.

[0045] The present application determines the SOC change based on the voltage data and the current data, and calculates the SOC estimate value in combination with the initial SOC value. During the plateau period, the open-circuit voltage mapping table set and the dynamic internal resistance mapping table set are used for interpolation calculation to obtain the first and second correction values. Finally, the target SOC value is determined by combining the SOC estimate value and the two correction values. Through multiple data fusion and correction, the error caused by voltage stability during the plateau period is effectively compensated, and the accuracy and stability of the SOC estimation are improved.

[0046] It should be noted that the execution subject of the method of this embodiment can be a computing service device with data processing, network communication and program running functions, or it can be the above-mentioned lithium iron phosphate battery SOC correction device with the same or similar functions. This embodiment and the following embodiments will be described by taking the lithium iron phosphate battery SOC correction device as an example.

[0047] Based on this, the first embodiment of the SOC correction method of the lithium iron phosphate battery of the present application is proposed, please refer to Figure 1 , Figure 1This is a flow chart of the first embodiment of the SOC correction method for a lithium iron phosphate battery of the present application.

[0048] In this embodiment, the method includes the following steps:

[0049] S1: Determine the SOC change according to the voltage data and current data of the battery cell to be processed;

[0050] It should be noted that the battery cell is the basic unit inside the battery, which includes the positive electrode, negative electrode, electrolyte and other parts. The battery cell is the core component of the battery, and multiple battery cells can form a complete battery pack. Voltage data refers to the voltage value monitored in real time during the charging and discharging process of the battery cell, which is used to reflect the state of charge (SOC) and operating status of the battery cell. Current data refers to the current value passing through the battery cell during the charging and discharging process. Positive current indicates charging and negative current indicates discharging. Current data and voltage data jointly determine the charging and discharging behavior of the battery. The SOC change refers to the change in the SOC (state of charge) of the battery cell within a specific time. SOC indicates the percentage of the remaining capacity of the battery cell relative to its maximum capacity. The change in SOC can be calculated by the accumulation of current over time.

[0051] Specifically, the voltage and current data of the battery cells are monitored in real time through sensors. These data are collected periodically to ensure accurate tracking of the charging and discharging process of the battery cells. The monitored current data is used to determine whether it is currently in a charging or discharging state, and to record changes according to different current directions. The system will input this data into the battery management system (BMS) as the basis for SOC estimation.

[0052] Furthermore, the change in SOC is calculated by the ampere-hour integration method. Specifically, within a time interval, the system multiplies the collected current value by the time length to obtain the change in charge value within the time period. Then, this charge change value is compared with the total capacity of the battery to calculate the change in SOC. The change in SOC for each period of time is added or subtracted from the SOC at the previous moment to obtain an updated SOC estimate.

[0053] By monitoring voltage and current data in real time and calculating the SOC change, the system can accurately capture the charge and discharge status of the battery cell at every moment, avoiding the estimation error that may be caused by relying on a single data (such as voltage). Compared with simple voltage monitoring, this method can provide more accurate SOC estimation during the voltage plateau period, effectively avoiding the estimation deviation caused by voltage stability. In addition, this step can reflect the true state of the battery under different operating conditions (such as charge and discharge at different rates) through the accumulation calculation of current and time. This calculation method ensures the real-time and reliability of SOC estimation, provides accurate basic data for correction and optimization in subsequent steps, and helps to improve the safety of the battery management system and the service life of the battery.

[0054] S2: determining an estimated SOC value according to the SOC change and the initial SOC value;

[0055] It should be noted that the initial SOC value refers to the SOC value of the battery at the beginning of the calculation, which indicates the percentage of the remaining power in the battery cell to the total capacity at that moment. The initial SOC value is the basic reference point for subsequent SOC estimation and dynamic correction. The SOC estimation value is the current SOC value calculated based on the initial SOC value and the SOC change. It is the estimated result of the remaining power state of the battery cell at a specific moment, which is used to guide charging and discharging strategies and battery management.

[0056] Specifically, the initial SOC value is recorded at the beginning of the calculation, that is, the percentage of the remaining power in the battery cell to the total capacity at that moment. This initial SOC value may come from the record when the battery is fully charged, or the previous SOC estimation result is used as a reference starting point. After that, the system calculates the SOC change within a certain period of time through the real-time collected current data and the ampere-hour integration method, and adds or subtracts it from the initial SOC value.

[0057] Furthermore, the calculation method is adjusted according to the charge and discharge state of the battery cell: charging state: add the SOC change to the initial SOC value to calculate the current SOC estimate of the battery cell; discharging state: subtract the SOC change from the initial SOC value to estimate the current SOC. This process is accumulated hour by hour, that is, the SOC estimate in each time period will be used as the initial SOC value of the next stage, ensuring the continuity and real-time nature of the SOC estimation results.

[0058] This step ensures the accuracy and continuity of the SOC estimation by combining the SOC change with the initial SOC value. This method of addition or subtraction can not only track the battery's state of charge in real time, but also prevent the error of a single estimation from affecting the global result. In addition, this method provides basic data for responding to state changes of battery cells under different operating conditions (such as high-rate charge and discharge or plateau period). This method of updating the SOC hourly improves the robustness of the battery management system. The SOC estimation can be adjusted in real time during the charging and discharging process to avoid misjudgment caused by sensor drift or calculation errors, and provides a reliable basis for corrections during the subsequent plateau period. At the same time, this process ensures the safety of the battery in different application scenarios, avoids overcharging or over-discharging, and improves the battery life and system stability.

[0059] S3: if the battery cell to be processed is in a plateau period, interpolation calculation is performed through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value;

[0060] It should be noted that the plateau period refers to a certain SOC interval of the lithium iron phosphate battery during the charging and discharging process. The voltage change amplitude is small in this interval. Even if the SOC changes significantly, the voltage change is very limited. This makes it difficult to accurately estimate the SOC based solely on voltage data. The open circuit voltage mapping table set (OCV-map) is a correspondence table between the open circuit voltage and SOC of the battery cell measured and recorded in advance under different temperature and SOC conditions. These tables are used to supplement the nonlinear relationship between voltage and SOC during the plateau period. The dynamic internal resistance mapping table set (DCR-map) is a pre-established mapping table that records the internal resistance changes of the battery cell under different temperatures, SOC levels and charge and discharge rates, and is used to reflect the characteristics of the battery under dynamic working conditions. The first correction value is the SOC correction value obtained by interpolation of the open circuit voltage mapping table, which compensates for the estimation error caused by the insignificant voltage change during the plateau period. The second correction value is the SOC correction value obtained by interpolation based on the dynamic internal resistance mapping table, which reflects the impact of internal resistance changes on SOC estimation.

[0061] Specifically, determine and select the corresponding open circuit voltage mapping table (OCV-map) and dynamic internal resistance mapping table (DCR-map)

[0062] The system first selects the OCV table that best matches the current temperature conditions from the open circuit voltage mapping table set according to the current temperature of the battery cell to be processed. At the same time, according to the temperature and charge and discharge rate of the battery cell, the corresponding DCR table is selected from the dynamic internal resistance mapping table set. This step ensures that the selected mapping table accurately reflects the current operating conditions.

[0063] Furthermore, linear interpolation is performed between adjacent data points in the OCV table based on the current SOC estimate. If the SOC estimate does not fall exactly on a data point in the OCV table, the corresponding open circuit voltage is estimated by interpolation, and the first correction value is derived from this. In the DCR table, the internal resistance data point corresponding to the SOC range is found using the current charge and discharge rate and temperature, and the dynamic internal resistance correction value under the current SOC state is obtained by interpolation calculation. This internal resistance value reflects the impact of the dynamic behavior of the battery on the SOC.

[0064] By combining the OCV mapping table and the DCR mapping table for interpolation calculation during the plateau period, this method effectively compensates for the SOC estimation error during the voltage stable period. The open circuit voltage mapping table provides supplementary information of the nonlinear voltage-SOC relationship, so that the SOC estimation no longer depends on a single voltage signal. The introduction of the dynamic internal resistance mapping table fully considers the impact of temperature and rate changes on SOC, making the estimation result more accurate. This multi-table interpolation correction strategy improves the robustness and accuracy of SOC estimation and avoids the deviation caused by the single voltage estimation method during the plateau period. By introducing dynamic internal resistance correction, it can also reflect the actual state of the battery under complex working conditions, thereby improving the reliability of the battery management system (BMS), extending the battery life and ensuring the safe operation of the system.

[0065] S4: determining a target SOC value according to the SOC estimated value, the first correction value and the second correction value;

[0066] It should be noted that the target SOC value is the final SOC value obtained by combining the SOC estimation value, the first correction value and the second correction value, and serves as the basis for the battery management system (BMS) to manage the battery status in real time.

[0067] Specifically, the SOC estimation value, the first correction value and the second correction value are first compared to check whether the difference between them is within the preset threshold range. If the difference between the three values ​​exceeds the threshold, there may be an abnormality, such as sensor drift, data collection error, etc. The system will trigger an alarm and enter the abnormality handling process.

[0068] Furthermore, if the differences between the three key values ​​are within a reasonable range, the system will weight the SOC estimation value, the first correction value and the second correction value based on the first preset weight rule. During the plateau period, the weights of the first correction value and the second correction value are appropriately increased to compensate for the error of the SOC estimation value; during the non-plateau period, the weight of the SOC estimation value will be higher because the voltage change is more consistent with the SOC change.

[0069] This step ensures the accuracy of the final target SOC value by comprehensively calculating the SOC estimation value, the first correction value, and the second correction value. Especially during the plateau period, the error of the single voltage signal estimation is large, and the OCV and DCR corrections can effectively improve the accuracy of the SOC estimation. In addition, based on the flexible adjustment of the weight rules under different working conditions, the system can adapt to different charging and discharging states to achieve more accurate battery management. This multi-fusion calculation strategy enables the battery management system to accurately grasp the state of the battery cell in a complex environment, avoid the risk of overcharging or over-discharging, and ensure the safety and service life of the battery. At the same time, the determination of the target SOC value provides a reliable management basis for the system, which helps to optimize the charging and discharging efficiency of the battery.

[0070] This embodiment determines the SOC change according to the voltage data and current data of the battery cell to be processed; determines the SOC estimation value according to the SOC change and the initial SOC value; if the battery cell to be processed is in a plateau period, interpolation calculation is performed through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value; and determines the target SOC value according to the SOC estimation value, the first correction value and the second correction value. This embodiment determines the SOC change according to the voltage data and the current data, and calculates the SOC estimation value in combination with the initial SOC value. In the plateau period, the open circuit voltage mapping table set and the dynamic internal resistance mapping table set are used for interpolation calculation to obtain the first and second correction values. Finally, the target SOC value is determined by combining the SOC estimation value and the two correction values. Through multiple data fusion and correction, the error caused by voltage stability in the plateau period is effectively compensated, and the accuracy and stability of SOC estimation are improved.

[0071] Based on the above first embodiment, a second embodiment of the SOC correction method for a lithium iron phosphate battery of the present application is proposed. Figure 2 , Figure 2 This is a schematic diagram of a sub-process in the second embodiment of the SOC correction method for a lithium iron phosphate battery of the present application.

[0072] like Figure 2 As shown, in this embodiment, before step S3, the following is further included:

[0073] S3a: determining a voltage change and a current change of the battery cell to be processed according to the voltage data and the current data;

[0074] S3b: Acquire temperature data of the battery cell to be processed, and determine temperature change of the battery cell to be processed according to the temperature data;

[0075] S3c: Based on the voltage change, the current change and the temperature change, determine whether the battery cell to be processed is in the plateau period.

[0076] It should be noted that voltage change refers to the voltage change trend of the battery cell over a period of time, including voltage rise, fall or stability. It is used to determine the charge and discharge status of the battery cell and whether it is in the voltage plateau period. Current change refers to the current fluctuation of the battery cell during the charge and discharge process, including the current size, direction (charging or discharging) and changes over time. Temperature data refers to the real-time temperature value of the battery cell during operation. Temperature change describes the temperature change trend of the battery cell over time, which is used to analyze whether the temperature is stable and whether it may affect the battery status.

[0077] Specifically, the voltage, current and temperature of the battery cell are collected in real time through sensors, and these data are continuously recorded at set time intervals. Afterwards, the system will process the collected data and calculate the voltage change rate, current change rate and temperature change rate over a period of time. If the voltage changes little between multiple time points, it is considered that the battery cell voltage tends to be stable. Analyze whether the current fluctuation is maintained within a small range to determine whether the current battery cell is in a stable charging and discharging state. If the battery cell temperature fluctuates little over a period of time, it means that the temperature is relatively stable and will not have a significant impact on the voltage and internal resistance.

[0078] Furthermore, if the voltage remains stable for a certain period of time, that is, the change amplitude is lower than the preset threshold, the battery cell may be in a plateau period. When the current remains stable and there is no obvious fluctuation, it indicates that the current battery cell is in a constant charge and discharge state. The stability of the temperature verifies the authenticity of the voltage change. If the temperature fluctuation is small and the voltage change is not obvious, it further supports the judgment that the battery cell is in a plateau period. If the changes in the above three parameters all meet the stability conditions, the system will judge that the battery cell is in a plateau period; otherwise, it is considered that the battery cell has not entered the plateau period and the conventional SOC estimation method needs to be used for calculation.

[0079] By monitoring the changes in voltage, current and temperature, the system can accurately determine whether the battery cell is in a plateau period. This multi-parameter judgment method overcomes the limitations of relying solely on voltage monitoring and effectively improves the accuracy of SOC estimation during the plateau period. In addition, through the introduction of temperature data, the system can identify the impact of the environment on the state of the battery cell and ensure the reliability of the judgment results. The comprehensive judgment of this step lays the foundation for SOC correction during the plateau period, enabling the system to flexibly switch between different estimation strategies. During the plateau period, interpolation correction can be performed through the mapping table, while in the non-plateau period, the ampere-hour integration method is relied on for estimation, thereby improving the overall accuracy of SOC estimation and the safety of battery management.

[0080] Based on the above first embodiment, in this embodiment, step S3 includes:

[0081] S31: selecting, according to the current temperature of the battery cell to be processed, a corresponding open circuit voltage mapping table in the preset open circuit voltage mapping table set as a first correction table;

[0082] S32: performing interpolation calculation on the SOC estimation value based on the first correction table to obtain the first correction value;

[0083] S33: selecting a corresponding dynamic internal resistance mapping table in the preset dynamic internal resistance mapping table set as a second correction table according to the current temperature and current charge and discharge rate of the battery cell to be processed;

[0084] S34: Based on the second correction table, interpolate the SOC estimation value to obtain the second correction value.

[0085] It should be noted that the open circuit voltage mapping table set (OCV-map) contains multiple mapping tables of the relationship between battery SOC (state of charge) and open circuit voltage under different temperature conditions. Each table corresponds to a specific temperature environment and is used to reflect the voltage change characteristics of the battery at different temperatures. The first correction table is a mapping table corresponding to the current battery cell temperature selected from the OCV mapping table set, which is used to interpolate and correct the SOC estimation value to compensate for the error caused by the insignificant voltage change during the plateau period. The dynamic internal resistance mapping table set (DCR-map) records the internal resistance change relationship of the battery cell at different temperatures, SOC levels and charge and discharge rates. It is used to reflect the resistance characteristics of the battery cell under dynamic working conditions. The second correction table is a mapping table selected from the DCR mapping table set based on the current temperature and charge and discharge rate of the battery cell, which is used to further correct the SOC estimation value. The charge and discharge rate indicates the ratio between the current battery cell charge or discharge current and its rated capacity, such as 1C, 0.5C, etc. This parameter affects the internal resistance performance and working state of the battery.

[0086] Specifically, according to the current temperature of the battery cell, the open circuit voltage mapping table corresponding to the temperature is searched in the OCV mapping table set and used as the first correction table. According to the position of the SOC estimate in the mapping table, the system determines that it is located between two adjacent data points. The linear interpolation method is used to calculate between these two data points to obtain the voltage corresponding value of the SOC estimate. This interpolation result is used as the first correction value to compensate for the error caused by the unclear relationship between voltage and SOC during the plateau period.

[0087] Furthermore, according to the current temperature and charge / discharge rate of the battery cell, a corresponding dynamic internal resistance mapping table is selected from the DCR mapping table set and used as the second correction table. According to the position of the SOC estimated value in the internal resistance mapping table, it is judged that it is located between two adjacent SOC data points. Through linear interpolation calculation, the system estimates the corresponding internal resistance correction value between the two data points and uses it as the second correction value. This correction value is used to reflect the impact of temperature and rate changes on the internal resistance.

[0088] By combining the OCV mapping table and the DCR mapping table, the accuracy of SOC estimation is effectively improved. First, the introduction of the OCV mapping table compensates for the error in SOC estimation when the voltage change of the battery is not obvious during the plateau period, making the estimation result more accurate. Secondly, the DCR mapping table reflects the impact of temperature and charge and discharge rate on the internal resistance of the battery cell, and further corrects the SOC estimation value to ensure its applicability under different working conditions. This dual correction mechanism not only improves the accuracy and robustness of SOC estimation, but also can flexibly adjust the estimation strategy according to different working conditions, ensuring that the battery management system (BMS) can reliably control the battery status, thereby avoiding overcharging or over-discharging, extending the battery life, and improving the safety and stability of the system.

[0089] This embodiment determines the SOC change according to the voltage data and current data of the battery cell to be processed; determines the SOC estimation value according to the SOC change and the initial SOC value; if the battery cell to be processed is in a plateau period, interpolation calculation is performed through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value; and determines the target SOC value according to the SOC estimation value, the first correction value and the second correction value. This embodiment determines the SOC change according to the voltage data and the current data, and calculates the SOC estimation value in combination with the initial SOC value. In the plateau period, the open circuit voltage mapping table set and the dynamic internal resistance mapping table set are used for interpolation calculation to obtain the first and second correction values. Finally, the target SOC value is determined by combining the SOC estimation value and the two correction values. Through multiple data fusion and correction, the error caused by voltage stability in the plateau period is effectively compensated, and the accuracy and stability of SOC estimation are improved.

[0090] Based on the above second embodiment, a third embodiment of the SOC correction method of the lithium iron phosphate battery of the present application is proposed. Figure 3 , Figure 3 This is a schematic diagram of a sub-process in the third embodiment of the SOC correction method for a lithium iron phosphate battery of the present application.

[0091] In this embodiment, step S4 includes:

[0092] S41: determining whether a difference between the SOC estimation value, the first correction value, and the second correction value exceeds a preset difference threshold;

[0093] S42: If not, based on a first preset weight rule, weighted sum the SOC estimation value, the first correction value, and the second correction value to obtain the target SOC value.

[0094] It should be noted that the difference value refers to the difference between the SOC estimation value, the first correction value and the second correction value, which is used to measure whether these estimation results are consistent. The preset difference threshold is a tolerance range pre-set by the system, which is used to determine whether the difference between multiple SOC estimation results is within a reasonable range. The first preset weight rule is a weight ratio assigned to the SOC estimation value, the first correction value and the second correction value according to the importance of different parameters, which is used to calculate the target SOC value by weighted summation.

[0095] Specifically, the differences between the SOC estimation value, the first correction value, and the second correction value are compared one by one, and the difference values ​​between them are calculated. If all these difference values ​​are within the preset difference threshold range set by the system, it is considered that the consistency between the various estimation values ​​is good, and a weighted sum calculation can be performed. If a certain difference value exceeds the threshold, the system may consider that a certain estimation result is abnormal, for example, due to sensor drift or data error. At this time, the system will trigger an alarm or enter the abnormality handling process, and will not directly use these data to calculate the target SOC value.

[0096] Furthermore, according to the operating conditions of the system (such as during a plateau period or a non-plateau period), weights are assigned to the estimated SOC value, the first correction value, and the second correction value. For example, during a plateau period, the weights of the first correction value and the second correction value may be increased. The estimated SOC value, the first correction value, and the second correction value are weighted and summed according to the set weight ratio to calculate the target SOC value. The target SOC value is used as the final output to guide the operation of the battery management system.

[0097] By judging whether the difference value exceeds the preset threshold, the system can filter out estimation results that may have errors or anomalies to ensure the reliability and accuracy of the target SOC value. At the same time, based on the first preset weight rule, weighted summation calculation is performed, so that the system can flexibly adapt to the SOC estimation needs under different working conditions. The introduction of this weighted summation method avoids the error accumulation caused by a single estimation method and improves the robustness and adaptability of SOC estimation. The system can pay more attention to the correction value during the plateau period and rely more on the SOC estimation value during the non-plateau period, so that accurate SOC estimation results can be output in various states to ensure the safety and stability of battery operation.

[0098] Based on the above second embodiment, in this embodiment, before step S4, the following is further included:

[0099] S4A: If the battery cell to be processed is not in a plateau period, based on a second preset weight rule, the SOC estimation value, the first correction value and the second correction value are weighted and summed to obtain the target SOC value; wherein the weight corresponding to the SOC estimation value in the second preset weight rule is greater than the weight corresponding to the SOC estimation value in the first preset weight rule.

[0100] It should be noted that the second preset weight rule refers to a weighted rule used when the battery cell is not in a plateau period, and the weight ratio of the SOC estimation value is higher than the first preset weight rule in the plateau period.

[0101] Specifically, first determine whether the battery cell is in a plateau period based on the changes in voltage, current and temperature data. If the system detects that the voltage changes significantly with SOC, it determines that the battery cell is not in a plateau period and enters the normal SOC estimation process.

[0102] Furthermore, in the non-plateau period, since the voltage change can more directly reflect the SOC state, the system will rely on the SOC estimate as the main reference, so the weight ratio of the SOC estimate is relatively large. The weight ratio of the first correction value and the second correction value at this time will be relatively small. According to the second preset weight rule, the SOC estimate, the first correction value and the second correction value are weighted and summed to obtain the final target SOC value. Since the battery cell is not in a plateau period at this time, the system mainly relies on the SOC estimate to reflect the real-time status of the battery.

[0103] By adopting the second preset weight rule, this step ensures that the system relies on the SOC estimate first when the battery cell is not in the plateau period, making full use of the accuracy and real-time performance of the ampere-hour integration method. This weighting strategy avoids the errors that may be caused by relying on the OCV and DCR correction values ​​when the voltage changes significantly, thereby improving the adaptability and accuracy of the SOC estimation. In addition, by flexibly switching the weight rules, the system can adapt to different working conditions, focusing on the correction value during the plateau period and relying on the SOC estimate during the non-plateau period. This strategy improves the robustness of the battery management system and ensures that the battery can output accurate SOC values ​​in various states, thereby optimizing the charge and discharge control strategy, extending the battery life and ensuring the safety and stability of the system.

[0104] Based on the above second embodiment, in this embodiment, after step S4, the following is further included:

[0105] S4a: verifying the target SOC value based on a preset SOC range standard;

[0106] S4b: If the verification is successful, the current SOC state of the battery cell to be processed is updated based on the target SOC value.

[0107] It should be noted that the SOC range standard is a pre-set reasonable range or threshold of SOC, which is used to determine whether the target SOC value is within a safe and effective range. For example, SOC should generally be between 0% and 100%, but in some application scenarios there may be stricter range requirements (such as 20% to 80%). The current SOC state refers to the SOC value of the battery cell at the current point in time, which represents the remaining capacity of the battery cell and is the key data for the battery management system (BMS) to perform charge and discharge control and safety protection.

[0108] Specifically, the calculated target SOC value is compared with the preset SOC range standard to check whether the value is within a reasonable SOC range. For example: if the SOC value exceeds 100%, it indicates that there may be errors in the calculation, such as current accumulation errors or sensor drift. If the SOC value is lower than 0% or other set minimum thresholds, it may indicate abnormal battery consumption or misjudgment of the status. If the target SOC value fails to pass verification, the system will trigger a corresponding alarm and take measures as appropriate, such as adjusting calculation parameters or recalculating the SOC value to ensure the accuracy of the battery status.

[0109] Furthermore, if the target SOC value passes the range verification, the system will use this value as the current SOC state of the battery cell and record this value in the battery management system (BMS) for subsequent charge and discharge management. The updated SOC state is used as the initial SOC value for the next time period, and the battery charge and discharge strategy is adjusted according to this state. For example, when the SOC approaches the upper limit, the system will limit further charging to prevent overcharging; when the SOC approaches the lower limit, the system may stop discharging to prevent over-discharge.

[0110] By verifying the target SOC value based on the preset SOC range standard, this step ensures the accuracy and reliability of the SOC value and avoids battery damage or performance degradation that may be caused by incorrect SOC calculation. After verification, the current SOC status of the battery cell is updated in time, providing reliable basic data for the system's charge and discharge control and safety management. This process improves the robustness of the battery management system and ensures the continuity of SOC estimation and management. At the same time, through reasonable SOC update and control strategies, risks such as overcharging and over-discharging of the battery can be avoided, the battery life can be extended, and the safe and stable operation of the system can be guaranteed.

[0111] This embodiment determines the SOC change according to the voltage data and current data of the battery cell to be processed; determines the SOC estimation value according to the SOC change and the initial SOC value; if the battery cell to be processed is in a plateau period, interpolation calculation is performed through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value; and determines the target SOC value according to the SOC estimation value, the first correction value and the second correction value. This embodiment determines the SOC change according to the voltage data and the current data, and calculates the SOC estimation value in combination with the initial SOC value. In the plateau period, the open circuit voltage mapping table set and the dynamic internal resistance mapping table set are used for interpolation calculation to obtain the first and second correction values. Finally, the target SOC value is determined by combining the SOC estimation value and the two correction values. Through multiple data fusion and correction, the error caused by voltage stability in the plateau period is effectively compensated, and the accuracy and stability of SOC estimation are improved.

[0112] In one embodiment, a method for correcting the SOC of a lithium iron phosphate battery during the charge and discharge process is provided, comprising the following stages: obtaining a discharge DCR-map (including three test durations of 2s, 5s and 10s) and a dynamic discharge OCV-map when discharging from 100% SOC to 0% at 0.2C, 0.33C, 0.5C, 1C, 2C, and MaxC (maximum discharge rate) at (-30°C, -20°C, -10°C, 0°C, 10°C, 25°C, 45°C, and 55°C). At the same time, obtain a dynamic charging OCV-map and a charging DCR-map (10s, 30s, 60s) tested according to the charging map. When the battery cell is charged / discharged during the discharge plateau, the SOC is obtained by comparing the dynamic charging / discharging OCV-maps at different rates according to the current temperature T, charging / discharging current I and duration t, and battery cell voltage V. V1 At the same time, according to the changes in charge / discharge current and cell voltage, the charge / discharge DCR at this time can be obtained. By comparing the charge / discharge DCR-map at different rates, the linear difference is taken to obtain the SOC R1 ; At the same time, according to the on-time points, SOC Ah ; The formula to define the true SOC is, SOC real =A*SOC V1 +B*SOC R1 +C*SOC Ah , (where A, B, and C are proportional coefficients, A+B+C=1, and real-time correction is performed based on the SOC correction result in the non-platform area). When the accuracy requirement of SOC is further improved, it can be extended to:

[0113] Where n is a constant. The value of n can be corrected based on actual needs and test verification data to obtain the true SOC at the end of the plateau discharge.

[0114] The present application also provides a lithium iron phosphate battery SOC correction device, please refer to Figure 4 , Figure 4 This is a schematic diagram of the module structure of the SOC correction device for a lithium iron phosphate battery in an embodiment of the present application. The SOC correction device for a lithium iron phosphate battery includes:

[0115] A preliminary module 401 is used to determine the SOC change according to the voltage data and current data of the battery cell to be processed;

[0116] An estimation module 402, configured to determine an estimated SOC value according to the SOC change and an initial SOC value;

[0117] A correction module 403 is used to obtain a first correction value and a second correction value by performing interpolation calculation through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set if the battery cell to be processed is in a plateau period;

[0118] The target module 404 is configured to determine a target SOC value according to the estimated SOC value, the first correction value, and the second correction value.

[0119] The SOC correction device for a lithium iron phosphate battery provided in the embodiment of the present application adopts the SOC correction method for a lithium iron phosphate battery in the above embodiment, and can solve the technical problem of how to improve the SOC estimation accuracy of a lithium iron phosphate battery. Compared with the prior art, the beneficial effects of the SOC correction device for a lithium iron phosphate battery provided in the embodiment of the present application are the same as the beneficial effects of the SOC correction method for a lithium iron phosphate battery provided in the above embodiment, and other technical features in the SOC correction device for a lithium iron phosphate battery are the same as the features disclosed in the above embodiment method, and are not described in detail here.

[0120] The present application provides a lithium iron phosphate battery SOC correction device, which includes: at least one processor; and a memory connected to the at least one processor in communication; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the lithium iron phosphate battery SOC correction method in the above-mentioned embodiment.

[0121] Reference below Figure 5, which shows a schematic diagram of the structure of a lithium iron phosphate battery SOC correction device suitable for implementing the embodiment of the present application. The lithium iron phosphate battery SOC correction device in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 5 The lithium iron phosphate battery SOC correction device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0122] like Figure 5 As shown, the lithium iron phosphate battery SOC correction device may include a processing device 1001 (such as a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the lithium iron phosphate battery SOC correction device are also stored. The processing device 1001, ROM1002 and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; storage devices 1003 including, for example, a magnetic tape, a hard disk, etc.; and communication devices 1009. The communication device 1009 can allow the lithium iron phosphate battery SOC correction device to communicate wirelessly or wired with other devices to exchange data. Although the figure shows a lithium iron phosphate battery SOC correction device with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or have alternatively.

[0123] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0124] The lithium iron phosphate battery SOC correction device provided by the present application adopts the lithium iron phosphate battery SOC correction method in the above embodiment, which can solve the technical problem of how to improve the SOC estimation accuracy of the lithium iron phosphate battery. Compared with the prior art, the beneficial effects of the lithium iron phosphate battery SOC correction device provided by the present application are the same as the beneficial effects of the lithium iron phosphate battery SOC correction method provided by the above embodiment, and the other technical features of the lithium iron phosphate battery SOC correction device are the same as the features disclosed in the previous embodiment method, which will not be repeated here.

[0125] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0126] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0127] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the lithium iron phosphate battery SOC correction method in the above-mentioned embodiment.

[0128] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, 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 disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above. The computer-readable storage medium may be included in the SOC correction device for the lithium iron phosphate battery; or may exist independently without being assembled into the SOC correction device for the lithium iron phosphate battery.

[0129] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by the lithium iron phosphate battery SOC correction device, the lithium iron phosphate battery SOC correction device: determines the SOC change according to the voltage data and current data of the battery cell to be processed; determines the SOC estimation value according to the SOC change and the initial SOC value; if the battery cell to be processed is in a plateau period, interpolation calculation is performed through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value; and determines the target SOC value according to the SOC estimation value, the first correction value and the second correction value. The computer program code for performing the operation of the present application can be written in one or more programming languages ​​or a combination thereof, and the programming language includes an object-oriented programming language such as Java, Smalltalk, C++, and a conventional procedural programming language such as "C" language or a similar programming language. The program code can be executed completely on the user's computer, partially on the user's computer, as an independent software package, partially on the user's computer and partially on a remote computer, or completely on a remote computer or server. In the case of a remote computer, 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 it can be connected to an external computer (for example, through the Internet using an Internet service provider).

[0130] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0131] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0132] The readable storage medium provided in the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned lithium iron phosphate battery SOC correction method, and can solve the technical problem of how to improve the SOC estimation accuracy of lithium iron phosphate batteries. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in the present application are the same as the beneficial effects of the lithium iron phosphate battery SOC correction method provided in the above-mentioned embodiment, and will not be repeated here.

[0133] An embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the above-mentioned lithium iron phosphate battery SOC correction method.

[0134] The computer program product provided in this application can solve the technical problem of how to improve the SOC estimation accuracy of lithium iron phosphate batteries. Compared with the prior art, the beneficial effects of the computer program product provided in the embodiment of this application are the same as the beneficial effects of the lithium iron phosphate battery SOC correction method provided in the above embodiment, which will not be repeated here.

[0135] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent processing scope of the present application.

Claims

1. A method for correcting SOC of a lithium iron phosphate battery, characterized in that: The method comprises: Determine the SOC change according to the voltage data and current data of the battery cell to be processed; Determining an estimated SOC value according to the SOC change and an initial SOC value; If the battery cell to be processed is in a plateau period, interpolation calculation is performed through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value; A target SOC value is determined according to the SOC estimated value, the first correction value, and the second correction value.

2. The method according to claim 1, characterized in that Before the step of performing interpolation calculation to obtain the first correction value and the second correction value by using a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set if the battery cell to be processed is in a plateau period, the step further includes: Determine the voltage change and current change of the battery cell to be processed according to the voltage data and the current data; Acquiring temperature data of the battery cell to be processed, and determining temperature changes of the battery cell to be processed according to the temperature data; Based on the voltage change, the current change and the temperature change, it is determined whether the battery cell to be processed is in the plateau period.

3. The method according to claim 1, characterized in that If the battery cell to be processed is in a plateau period, the step of performing interpolation calculation through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set to obtain a first correction value and a second correction value includes: According to the current temperature of the battery cell to be processed, selecting the corresponding open circuit voltage mapping table in the preset open circuit voltage mapping table set as the first correction table; Based on the first correction table, interpolate the SOC estimation value to obtain the first correction value; According to the current temperature and the current charge and discharge rate of the battery cell to be processed, selecting a corresponding dynamic internal resistance mapping table in the preset dynamic internal resistance mapping table set as a second correction table; Based on the second correction table, the SOC estimation value is interpolated to obtain the second correction value.

4. The method according to claim 1, characterized in that The step of determining a target SOC value according to the SOC estimated value, the first correction value, and the second correction value comprises: Determining whether a difference between the SOC estimation value, the first correction value, and the second correction value exceeds a preset difference threshold; If not, based on a first preset weight rule, the SOC estimation value, the first correction value and the second correction value are weighted and summed to obtain the target SOC value.

5. The method according to claim 4, characterized in that Before the step of determining the target SOC value according to the SOC estimated value, the first correction value and the second correction value, the method further includes: If the battery cell to be processed is not in a plateau period, based on a second preset weight rule, the SOC estimation value, the first correction value and the second correction value are weighted and summed to obtain the target SOC value; wherein the weight corresponding to the SOC estimation value in the second preset weight rule is greater than the weight corresponding to the SOC estimation value in the first preset weight rule.

6. The method according to claim 4, characterized in that After the step of determining the target SOC value according to the SOC estimated value, the first correction value and the second correction value, the method further includes: Verifying the target SOC value based on a preset SOC range standard; If the verification is successful, the current SOC state of the battery cell to be processed is updated based on the target SOC value.

7. A lithium iron phosphate battery SOC correction device, characterized in that: The device comprises: A preliminary module, used to determine the SOC change according to the voltage data and current data of the battery cell to be processed; An estimation module, used for determining an estimated SOC value according to the SOC change amount and an initial SOC value; A correction module, configured to obtain a first correction value and a second correction value by performing interpolation calculation through a preset open circuit voltage mapping table set and a preset dynamic internal resistance mapping table set if the battery cell to be processed is in a plateau period; A target module is used to determine a target SOC value according to the SOC estimation value, the first correction value and the second correction value.

8. A computer device, characterized in that: The device comprises: a memory, a processor, and a lithium iron phosphate battery SOC correction program stored in the memory and executable on the processor, wherein the lithium iron phosphate battery SOC correction program is configured to implement the steps of the lithium iron phosphate battery SOC correction method as described in any one of claims 1 to 6.

9. A storage medium, characterized in that: The storage medium stores a lithium iron phosphate battery SOC correction program, and when the lithium iron phosphate battery SOC correction program is executed by the processor, the steps of the lithium iron phosphate battery SOC correction method according to any one of claims 1 to 6 are implemented.

10. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the steps of the lithium iron phosphate battery SOC correction method according to any one of claims 1 to 6 are implemented.

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