Battery SOC estimation method and system, storage medium and electronic equipment

Abstract

The invention discloses a battery SOC estimation method and system, a storage medium and electronic equipment, and the method comprises the steps: obtaining open-circuit voltage and SOC data at multiple groups of temperatures, dividing a platform region from a voltage slope, dynamically updating an OCV-SOC curve corresponding to the current temperature and a platform region interval through two times of interpolation, and determining whether the current voltage is in the platform region or not. The SOC is calculated by adaptively selecting ampere-hour integration (platform area) or extended Kalman filtering (non-platform area). The system comprises a data acquisition module, a data processing module, a twice interpolation module and a calculation module. According to the scheme, a traditional mode of defining a platform area in a solidified SOC interval is abandoned, the platform area is dynamically recognized, the algorithm is accurately matched, the OCV-SOC curve precision is improved, the advantage of multi-algorithm fusion is achieved, and the local and overall precision of SOC estimation is effectively improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of automobile batteries, and in particular relates to a battery SOC estimation method, system, storage medium and electronic equipment. Background Art

[0002] The state of charge (SOC), as a key parameter that characterizes the percentage of remaining charge in a battery, is the core state variable of the battery management system (BMS). Its accuracy plays a vital role in the realization of functions such as estimating the remaining mileage of electric vehicles, setting charge and discharge power limits, and overcharge and over-discharge protection.

[0003] At present, SOC estimation methods can be roughly divided into two categories according to the application scenarios: engineering applications and laboratory explorations: one is the engineering application method that uses single or comprehensive algorithms such as ampere-hour integration, open circuit voltage (OCV) correction, and Kalman filtering; the other is the laboratory exploratory method based on electrochemical property modeling or big data driving. The former has the advantage of rapid engineering application and can meet the basic functional requirements of BMS, while the latter has a relatively high technical threshold because it needs to build a complex electrochemical model or rely on large-scale computing power training supported by massive data. In view of the above characteristics, the current SOC estimation in the engineering field mainly adopts the first type of method. After continuous optimization, the engineering application level of this type of method has reached a certain level of accuracy. By introducing more optimization and correction algorithms, it is gradually adapting to the increasing demand for SOC accuracy.

[0004] However, current BMS engineering applications still primarily rely on the ampere-hour integration method combined with the open-circuit voltage method for SOC calculation, with only a few scenarios employing the extended Kalman filter algorithm to improve estimation accuracy. Existing algorithms are either single-form or, despite integrating multiple algorithms, lack rational strategies. This makes it difficult to effectively improve SOC estimation and the estimation accuracy to meet actual requirements. Furthermore, traditional methods often define the open-circuit voltage plateau from the perspective of SOC, presetting a fixed SOC range (e.g., 20%-90%) as the plateau. This definition has theoretical flaws and is difficult to accurately reflect the actual voltage plateau characteristics of the battery in actual operating environments. Summary of the Invention

[0005] The purpose of the present invention is to provide a battery SOC estimation method, system, storage medium and electronic device to solve the problems in the prior art.

[0006] To this end, the present invention provides a battery SOC estimation method, the steps comprising:

[0007] Acquire test data sets at multiple temperature groups, wherein the test data sets include open circuit voltage and its corresponding SOC;

[0008] Performing data processing on the test data group to obtain open circuit voltage platform region 1 corresponding to a plurality of groups of the test data groups;

[0009] Input the current temperature, interpolate the multiple test data sets for the first time, and obtain the interpolation data set corresponding to the current temperature;

[0010] Performing a quadratic interpolation on the open circuit voltage platform region one to obtain an open circuit voltage platform region two corresponding to the current temperature;

[0011] The current voltage is obtained, and based on whether the current voltage is within the range of the second open circuit voltage platform zone, a corresponding calculation method is selected to calculate the SOC corresponding to the current temperature.

[0012] As a further description of the above technical solution, after obtaining the second open circuit voltage platform range corresponding to the current temperature, when the battery system meets a preset condition, the open circuit voltage is corrected based on the interpolation data set.

[0013] As a further description of the above technical solution, the step of processing the test data group to obtain the open circuit voltage platform regions corresponding to the plurality of test data groups includes:

[0014] Obtaining a corresponding curve of the open circuit voltage and SOC;

[0015] Obtaining the slope of the curve, and dividing the curve into region 1 and region 2 based on the slope;

[0016] The open circuit voltage platform region 1 is determined according to the open circuit voltage of the region 1.

[0017] As a further description of the above technical solution, when a preset condition is met, correcting the open circuit voltage based on the interpolation data set includes:

[0018] The preset condition is the open circuit voltage correction condition;

[0019] If the battery system does not meet the open circuit voltage correction condition, the current SOC storage value is read as the SOC initial value;

[0020] If the battery system meets the open circuit voltage correction condition, the SOC is corrected based on the interpolation data set.

[0021] As a further description of the above technical solution, the open circuit voltage correction condition includes that the battery system rest time is greater than a preset time, and the open circuit voltage is not within the range of the open circuit voltage platform zone II.

[0022] As a further description of the above technical solution, the step of selecting a corresponding calculation method to calculate the SOC corresponding to the current temperature based on whether the current voltage is within the range of the open circuit voltage platform zone II includes:

[0023] If the current voltage is within the range of interval 2 of the open circuit voltage platform region, the SOC is calculated using ampere-hour integration;

[0024] If the current voltage is in a range other than the open circuit voltage platform range, the SOC is calculated using an extended Kalman filter algorithm.

[0025] On the other hand, a battery SOC estimation system is also provided, comprising:

[0026] A data acquisition module, wherein the data acquisition module is used to obtain test data groups at multiple temperature groups;

[0027] A data processing module, configured to perform data processing on the test data group to obtain an open circuit voltage platform region 1 corresponding to each of a plurality of test data groups;

[0028] Interpolation module 1, after inputting the current temperature, interpolating the plurality of test data groups for the first time to obtain an interpolation data group corresponding to the current temperature;

[0029] Interpolation module 2, the interpolation module 2 is used to perform a first and second interpolation on the open circuit voltage platform region to obtain a second open circuit voltage platform region corresponding to the current temperature;

[0030] A calculation module is used to obtain a current voltage and, based on whether the current voltage is within the range of the open circuit voltage platform zone II, select a corresponding calculation method to calculate the SOC corresponding to the current temperature.

[0031] As a further description of the above technical solution, a correction module is included, and the correction module is used to correct the open circuit voltage based on the interpolation data group when the battery system meets the preset conditions.

[0032] On the other hand, a computer-readable storage medium is provided which stores a computer program for a battery SOC estimation method, wherein the computer program enables a computer to execute the battery SOC estimation method according to any one of claims 1 to 4.

[0033] In another aspect, an electronic device is provided, comprising:

[0034] one or more processors; memory; and

[0035] One or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the programs including instructions for executing the battery SOC estimation method according to any one of claims 1 to 4.

[0036] Beneficial effects:

[0037] The present invention provides a battery SOC estimation method, system, storage medium and electronic device, abandoning the traditional method of defining the open-circuit voltage platform area by solidifying the SOC interval, and finely dividing the platform area and non-platform area based on the voltage itself. At the same time, the OCV-SOC curve is updated in real time to provide a more accurate mathematical relationship, thereby improving the local SOC estimation accuracy when a single algorithm is executed. It can also more accurately identify the open-circuit voltage platform area, and accordingly allocate the optimal algorithm selection under different working conditions, giving full play to the advantages of multi-algorithm fusion, and effectively improving the overall accuracy of SOC estimation. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0039] Figure 1 This is a flow chart of the battery SOC estimation method provided by the present invention.

[0040] Figure 2 This is a graph of OCV-SOC test data at different temperatures.

[0041] Figure 3 The open circuit voltage platform area curve corresponding to the OCV-SOC test data at different temperatures.

[0042] Figure 4 This is the OCV-SOC data curve obtained by the first interpolation at zero °C.

[0043] Figure 5 The open circuit voltage platform curve of OCV-SOC obtained by quadratic interpolation at zero °C. DETAILED DESCRIPTION

[0044] The present invention may be more readily understood by referring to the following detailed description of preferred embodiments of the present invention and the included Examples. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention pertains. In the event of a conflict, the definitions in this specification shall prevail.

[0045] The present invention provides a battery SOC estimation method, system, storage medium and electronic device. The existing lithium-ion battery SOC estimation has the following problems: the ampere-hour integral error accumulates, the open-circuit voltage correction efficiency is low, the extended Kalman filter is prone to error correction in the platform area, and the traditional definition of the platform area based on the SOC interval has theoretical defects.

[0046] The technical concept of the present invention is to dynamically identify the open-circuit voltage platform area from the voltage slope through two-layer derivative interpolation based on multiple sets of OCV-SOC data from offline tests, and update the OCV-SOC curve and the corresponding platform area in real time according to the temperature. When the battery is powered on, it first determines whether the open-circuit voltage correction conditions are met, and then adaptively switches the ampere-hour integration or extended Kalman filter algorithm according to whether the current voltage is in the platform area to improve the SOC estimation accuracy.

[0047] like Figure 1-3 As shown, a battery SOC estimation method includes the following steps:

[0048] Acquire test data sets under multiple temperature groups, wherein the test data sets include open circuit voltage and its corresponding SOC, wherein each temperature group corresponds to multiple open circuit voltages and SOCs, for example, under the temperature conditions of -20°C, 20°C and 50°C, acquire 15-25 groups of OCV-SOC data curves (such as Figure 2 ), for example, the OCV-SOC data curve is named OCV_1, the OCV-SOC data curve corresponding to 20°C is named OCV_2, and the OCV-SOC data curve corresponding to 50°C is named OCV_3; wherein the test data group can be obtained by performing offline testing on the battery.

[0049] The test data sets are processed to obtain intervals 1 of the open circuit voltage platform regions corresponding to the multiple test data sets. Specifically, the slopes are calculated for the multiple test data sets, and the open circuit voltage platform region and non-platform region are divided based on the slopes combined with the curves formed by the multiple test data sets. The two ends of the open circuit voltage platform region are then confirmed. For example, the platform region of OCV_1 is confirmed to be interval AB, the platform region of OCV_2 is confirmed to be interval CD, and the platform region of OCV_3 is confirmed to be interval EF. That is, the present application confirms the open circuit voltage platform region from the voltage, rather than the traditional method of solidifying or specifying a certain SOC interval (such as 20%-90%) as the open circuit voltage platform region. This avoids the problem of platform region division distortion caused by the non-constant relationship between OCV and SOC and the need to correct the SOC value.

[0050] Input the current temperature, interpolate multiple test data sets for the first time, and obtain the interpolation data set corresponding to the current temperature (such as Figure 4Specifically, given the significant differences in the OCV-SOC curves of batteries at different temperatures (e.g., different curve shapes at -20°C, 20°C, and 50°C), using a fixed curve without considering the temperature factor will introduce significant errors. Temperature interpolation can dynamically generate the OCV-SOC curve corresponding to the current temperature, providing an accurate mathematical model that matches the actual operating temperature for the open circuit voltage correction and extended Kalman filter algorithm, thereby improving the accuracy of the open circuit voltage correction during the SOC estimation process.

[0051] The first and second interpolation of the open circuit voltage platform area can be performed by a linear interpolation algorithm to obtain the second open circuit voltage platform area corresponding to the current temperature, and determine the actual open circuit voltage platform area corresponding to the current temperature, so as to provide a basis for subsequent SOC calculation to improve the accuracy of SOC calculation. For example, Figure 5 Points G and H are interpolated longitudinally on OCV_now in the figure, and interval GH is the open circuit voltage platform interval 2 of the OCV-SOC curve in the current state;

[0052] The current voltage is obtained, and based on whether it is within the open-circuit voltage plateau region (Interval 2), the corresponding calculation method is selected to calculate the SOC corresponding to the current temperature. Specifically, the current voltage is determined to be within the plateau region of the current OCV-SOC curve, namely the open-circuit voltage plateau region (Interval 2). If so, the SOC is calculated using the ampere-hour integration algorithm. If not, the SOC is calculated using the extended Kalman filter algorithm. This leverages the advantages of different SOC estimation methods and improves the overall accuracy of SOC estimation. It is understandable that the voltage in the open-circuit voltage plateau region changes very slowly with SOC (the voltage slope approaches zero). At this time, the voltage signal cannot accurately reflect the actual SOC change. Algorithms that rely on voltage signals (such as the extended Kalman filter) are prone to miscorrection due to noise or slight fluctuations in the input signal. The ampere-hour integration algorithm calculates SOC by accumulating charge and discharge currents. Its principle is simple and real-time. When the voltage changes slightly in the plateau region, the accumulated error grows relatively slowly. It also does not rely on dynamic correction of the voltage signal, thus avoiding the misjudgment problem of the extended Kalman filter in the plateau region. In the non-plateau region, the voltage varies significantly with SOC (with a steeper voltage slope). At this point, the relationship between the voltage signal and SOC is more clearly defined, providing effective state feedback for the algorithm. The extended Kalman filter algorithm establishes a battery state-space model and recursively estimates SOC using voltage measurements, providing a self-correcting function. In the non-plateau region, where voltage varies significantly, the algorithm leverages the strong correlation between voltage and SOC to correct the accumulated error in the ampere-hour integral in real time, improving estimation accuracy and avoiding the loss of accuracy of a single ampere-hour integral due to accumulated errors.

[0053] In one embodiment, after obtaining the open circuit voltage platform zone interval 2 corresponding to the current temperature, when the battery system meets the preset conditions, the open circuit voltage is corrected based on the interpolation data set. Specifically, before obtaining the open circuit voltage platform zone interval 2 and calculating the SOC, when the battery system meets the preset conditions, the open circuit voltage is corrected based on the interpolation data set. That is, at the initial stage of powering on the battery system, it is first determined whether the open circuit voltage correction condition is met. If not, the SOC storage value is read. If met, the SOC is corrected by looking up the table using the currently updated OCV-SOC curve. In one embodiment, the open circuit voltage correction condition includes that the battery system has been stationary for more than 1 hour and the current voltage is not within the range of the open circuit voltage platform zone interval 2. It is understandable that the correspondence between the open circuit voltage OCV and the SOC can only be accurately obtained when the battery is in a stable open circuit state (i.e., no charge and discharge current, and the voltage is sufficiently stable). If the battery has not yet met the open circuit voltage correction condition at the initial stage of powering on, directly using OCV correction will cause SOC estimation errors due to signal distortion. If the correction is forced without determining the conditions, the voltage in the unstable state may be misjudged as OCV, thereby introducing an erroneous SOC correction value, which in turn reduces the estimation accuracy.

[0054] When the open-circuit voltage correction conditions are not met (e.g., the system has just been powered on and the battery is still in a dynamic state), the historically stored SOC value is read as the initial value. This value is based on valid data from the previous shutdown, ensuring the basic reliability of the initial estimate and preventing sudden changes or lack of basis for the initial SOC value. The stored value serves as a temporary benchmark, allowing the system to enter the SOC estimation process during startup. When subsequent conditions are met, OCV corrections are then performed to ensure the continuity of the estimation process. If the conditions are met (e.g., the battery is in a stable open-circuit state), the SOC is corrected through a table lookup, directly utilizing the corresponding relationship between OCV and SOC to perform a one-time calibration of the accumulated error in the ampere-hour integral, providing a more accurate initial value for subsequent estimates.

[0055] In one embodiment, the step of processing the test data group to obtain the open circuit voltage platform region corresponding to each of the plurality of test data groups includes:

[0056] Obtain the corresponding curve of open circuit voltage and SOC;

[0057] Obtain the slope of the curve and divide it into area 1 and area 2 based on the slope;

[0058] The open circuit voltage plateau region 1 is determined based on the open circuit voltage of region 1. Region 1 and region 2 correspond to the open circuit voltage plateau region and non-plateau region, respectively. It should be clear that the plateau region corresponds to the flat region in the curve. When dividing based on slope, the larger the slope, i.e., the steeper the curve, the non-plateau region, and the smaller the slope, i.e., the flatter part of the curve, corresponds to the open circuit voltage plateau region.

[0059] In one embodiment, when a preset condition is met, correcting the open circuit voltage based on the interpolation data set includes:

[0060] The preset condition is the open circuit voltage correction condition;

[0061] If the battery system does not meet the open circuit voltage correction condition, the current SOC storage value is read as the SOC initial value;

[0062] If the battery system meets the open circuit voltage correction condition, the SOC is corrected based on the interpolation data set.

[0063] This step initially selects a reliable correction method based on pre-defined conditions at system power-up. If these conditions are not met, historical data is relied upon. When these conditions are met, precise correction is enabled, ensuring high reliability of SOC estimation from the start-up phase and laying the foundation for the subsequent dynamic switching between ampere-hour integration and the extended Kalman filter.

[0064] In one embodiment, the open circuit voltage correction condition includes:

[0065] In one embodiment, the step of selecting a corresponding calculation method to calculate the SOC corresponding to the current temperature based on whether the current voltage is within the range of the open circuit voltage platform zone II includes:

[0066] If the current voltage is within the range of the open-circuit voltage plateau, the SOC is calculated using the ampere-hour integration algorithm. It should be noted that the ampere-hour integration algorithm calculates the SOC by accumulating the product of current and time (ampere-hours) during the battery's charge and discharge processes. This algorithm calculates the current SOC based on the battery's initial SOC and the integral of the charge and discharge currents. This algorithm is one of the fundamental methods used in SOC estimation engineering applications, with its simple principle and strong real-time performance.

[0067] If the current voltage is within the range of the non-open circuit voltage platform area, the extended Kalman filter algorithm is used to calculate the SOC. It should be clear that the extended Kalman filter algorithm is based on the battery state space model and uses recursive estimation to fuse the system model prediction value with the actual measurement value (such as voltage) to dynamically correct the SOC and has self-correction capabilities.

[0068] Through this step, the platform area can be dynamically identified based on the voltage itself, breaking the limitations of the traditional fixed SOC range, making the algorithm switching strategy more in line with the actual voltage characteristics of the battery under different temperatures and working conditions, thereby improving the overall accuracy of SOC estimation.

[0069] On the other hand, the present invention also provides a battery SOC estimation system, comprising:

[0070] A data acquisition module is used to obtain test data sets at multiple temperatures;

[0071] A data processing module is used to process the test data group to obtain open circuit voltage platform region 1 corresponding to each of the multiple test data groups;

[0072] Interpolation module 1, after inputting the current temperature, interpolation module 1 first interpolates multiple test data sets to obtain the interpolation data set corresponding to the current temperature;

[0073] Interpolation module 2, interpolation module 2 is used to perform primary and secondary interpolation on the open circuit voltage platform area interval to obtain the open circuit voltage platform area interval 2 corresponding to the current temperature;

[0074] The calculation module is used to obtain the current voltage and, based on whether the current voltage is within the range of the open circuit voltage platform zone 2, select a corresponding calculation method to calculate the SOC corresponding to the current temperature.

[0075] In one embodiment, the estimation system further includes a correction module, configured to correct the open circuit voltage based on the interpolation data set when the battery system meets a preset condition.

[0076] In another aspect, the present invention further provides a computer-readable storage medium storing a computer program for executing the vehicle system operation protection method, wherein the computer program causes a computer to execute the following steps:

[0077] Acquire test data sets at multiple temperature groups, wherein the test data sets include open circuit voltage and its corresponding SOC;

[0078] Performing data processing on the test data group to obtain open circuit voltage platform intervals corresponding to the plurality of test data groups;

[0079] Input the current temperature, interpolate multiple test data sets for the first time, and obtain the interpolation data set corresponding to the current temperature;

[0080] Perform quadratic interpolation on the first and second intervals of the open circuit voltage platform region to obtain the second interval of the open circuit voltage platform region corresponding to the current temperature;

[0081] The current voltage is obtained, and based on whether the current voltage is within the range of the open circuit voltage platform zone 2, a corresponding calculation method is selected to calculate the SOC corresponding to the current temperature.

[0082] Among them, the computer-readable storage medium can be a computer storage medium or a communication medium. The communication medium includes any medium that facilitates the transmission of a computer program from one place to another. The computer storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer. For example, a computer-readable storage medium is coupled to a processor so that the processor can read information from the computer-readable storage medium and write information to the computer-readable storage medium. Of course, the computer-readable storage medium can also be an integral part of the processor. The processor and the computer-readable storage medium can be located in an application-specific integrated circuit (ASIC). In addition, the ASIC can be located in a user device. Of course, the processor and the computer-readable storage medium can also exist in a communication device as discrete components.

[0083] Specifically, the computer-readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random-access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk or optical disk. The storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0084] In another aspect, the present invention further provides an electronic device, comprising:

[0085] one or more processors; memory; and

[0086] One or more programs, wherein the one or more programs are stored in a memory and configured to be executed by one or more processors, the programs comprising steps for performing the following steps:

[0087] Acquire test data sets at multiple temperature groups, wherein the test data sets include open circuit voltage and its corresponding SOC;

[0088] Performing data processing on the test data group to obtain open circuit voltage platform intervals corresponding to the plurality of test data groups;

[0089] Input the current temperature, interpolate multiple test data sets for the first time, and obtain the interpolation data set corresponding to the current temperature;

[0090] Perform quadratic interpolation on the first and second intervals of the open circuit voltage platform region to obtain the second interval of the open circuit voltage platform region corresponding to the current temperature;

[0091] The current voltage is obtained, and based on whether the current voltage is within the range of the open circuit voltage platform zone 2, a corresponding calculation method is selected to calculate the SOC corresponding to the current temperature.

[0092] Memory is used to store computer programs. This memory may include high-speed random access memory (RAM) and non-volatile memory (NVM), such as at least one disk storage device. It can also be a USB flash drive, a mobile hard drive, a read-only memory, a magnetic disk, or an optical disk.

[0093] Specifically, the above-mentioned memory is an internal memory, which can be used to store computer-pointable program codes, and the executable program codes include instructions. The internal memory may include a program storage area and a data storage area. The program storage area may store an operating system, an application required for at least one function, etc. The data storage area may store data created during the use of the electronic device, etc. In addition, the internal memory may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, a universal flash storage (UFS), etc. The processor executes various functional applications and data processing of the electronic device by running instructions stored in the internal memory and / or instructions stored in a memory provided in the processor.

[0094] A processor is used to execute a computer program stored in a memory to implement the vehicle system operation protection method in the above embodiment. The processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in the present invention can be directly implemented as a hardware processor, or can be implemented by a combination of hardware and software modules in the processor.

[0095] Optionally, the memory can be independent or integrated with the processor. The above-mentioned processor may include one or more processing units, for example: the processor may include an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural-network processing unit (NPU), etc. Among them, different processing units can be independent devices or integrated into one or more processors. The controller can generate an operation control signal based on the instruction opcode and timing signal to complete the control of instruction fetching and execution.

[0096] When the memory is a device independent of the processor, the electronic device may further include a bus. The bus is used to connect the memory and the processor. The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be divided into address buses, data buses, control buses, etc.

[0097] It should be noted that, through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus the necessary general hardware platform. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or certain parts of the embodiment. In this article, relational 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 such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. Without further constraints, an element defined by the phrase "comprises a..." does not preclude the existence of additional identical elements in the process, method, article or apparatus that includes the element.

[0098] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A battery SOC estimation method, characterized in that the steps include: Acquire test data sets at multiple temperature groups, wherein the test data sets include open circuit voltage and its corresponding SOC; Performing data processing on the test data group to obtain open circuit voltage platform region 1 corresponding to a plurality of groups of the test data groups; Input the current temperature, interpolate the multiple test data sets for the first time, and obtain the interpolation data set corresponding to the current temperature; Performing a quadratic interpolation on the open circuit voltage platform region one to obtain an open circuit voltage platform region two corresponding to the current temperature; The current voltage is obtained, and based on whether the current voltage is within the range of the second open circuit voltage platform zone, a corresponding calculation method is selected to calculate the SOC corresponding to the current temperature.

2. The estimation method according to claim 1, wherein: After obtaining the second open circuit voltage platform region corresponding to the current temperature, when the battery system meets a preset condition, the open circuit voltage is corrected based on the interpolation data set.

3. The estimation method according to claim 1, wherein: The step of processing the test data group to obtain the open circuit voltage platform regions corresponding to the plurality of test data groups includes: Obtaining a corresponding curve of the open circuit voltage and SOC; Obtaining the slope of the curve, and dividing the curve into region 1 and region 2 based on the slope; The open circuit voltage platform region 1 is determined according to the open circuit voltage of the region 1.

4. The estimation method according to claim 2, characterized in that When a preset condition is met, correcting the open circuit voltage based on the interpolation data set includes: The preset condition is the open circuit voltage correction condition; If the battery system does not meet the open circuit voltage correction condition, the current SOC storage value is read as the SOC initial value; If the battery system meets the open circuit voltage correction condition, the SOC is corrected based on the interpolation data set.

5. The estimation method according to claim 4, characterized in that The open circuit voltage correction condition includes that the battery system rest time is greater than a preset time, and the open circuit voltage is not within the range of the second open circuit voltage platform range.

6. The estimation method according to claim 1, wherein: The step of selecting a corresponding calculation method to calculate the SOC corresponding to the current temperature based on whether the current voltage is within the range of the open circuit voltage platform zone II includes: If the current voltage is within the range of interval 2 of the open circuit voltage platform region, the SOC is calculated using ampere-hour integration; If the current voltage is in a range other than the open circuit voltage platform range, the SOC is calculated using an extended Kalman filter algorithm.

7. A battery SOC estimation system, characterized in that: include: A data acquisition module, wherein the data acquisition module is used to obtain test data groups at multiple temperature groups; A data processing module, configured to perform data processing on the test data group to obtain an open circuit voltage platform region 1 corresponding to each of a plurality of test data groups; Interpolation module 1, after inputting the current temperature, interpolating the plurality of test data groups for the first time to obtain an interpolation data group corresponding to the current temperature; Interpolation module 2, the interpolation module 2 is used to perform a first and second interpolation on the open circuit voltage platform region to obtain a second open circuit voltage platform region corresponding to the current temperature; A calculation module is used to obtain a current voltage and, based on whether the current voltage is within the range of the open circuit voltage platform zone II, select a corresponding calculation method to calculate the SOC corresponding to the current temperature.

8. The estimation system according to claim 7, wherein: A correction module is included, and the correction module is used to correct the open circuit voltage based on the interpolation data group when the battery system meets the preset conditions.

9. A computer-readable storage medium, characterized in that The computer stores a computer program for a battery SOC estimation method, wherein the computer program enables a computer to execute the battery SOC estimation method according to any one of claims 1 to 6.

10. An electronic device, characterized in that: include: one or more processors; Memory; as well as One or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the programs including instructions for executing the battery SOC estimation method according to any one of claims 1 to 6.

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