Power battery SOC correction method and device, electric vehicle and storage medium

Abstract

The invention provides a power battery SOC correction method and device, an electric vehicle and a storage medium, and relates to the technical field of electric vehicles. The method comprises the following steps: acquiring a charge-discharge current history of a battery to be detected in the current driving cycle; determining the current polarization degree of the to-be-detected battery according to the charging and discharging current process and a battery cumulative polarization model; according to the current polarization degree and a pre-constructed pulse depolarization model, determining the pulse charge and discharge frequency and the execution duration of the to-be-tested battery; according to the pulse charging and discharging frequency and the execution duration, the battery to be tested is controlled to execute pulse charging and discharging operation, namely, controllable charging and discharging pulses are actively applied, polarization voltage elimination is accelerated, depolarization time is greatly shortened, after execution is finished, SOC correction is conducted on the battery to be tested, the corrected SOC of the battery to be tested is obtained, and on-demand immediate correction is achieved; long-time parking and waiting are not needed, the SOC correction frequency of the power battery is improved, and the dynamic response capability of the system to the driving condition change is enhanced.

Description

Technical Field

[0001] This application relates to the field of battery management technology, and more specifically, to a method, apparatus, electric vehicle, and storage medium for correcting the state of charge (SOC) of a power battery. Background Technology

[0002] With the rapid development of the new energy vehicle industry, the accuracy of state estimation of power batteries, as the core power source, directly affects the safety, range, and lifespan of the entire vehicle. Among these factors, the accurate estimation of the battery's state of charge (SOC) is particularly crucial.

[0003] Currently, most mainstream SOC estimation methods rely on open circuit voltage (OCV). They are mainly based on the inherent mapping relationship between the battery's open circuit voltage (OCV) and SOC for calibration. However, this method requires the battery to be in a completely quiescent or fully depolarized state to eliminate the influence of polarization voltage and thus obtain a stable terminal voltage.

[0004] However, in actual vehicle usage scenarios, achieving "complete depolarization" usually requires several hours or even longer of rest, which forces the SOC correction cycle to be longer and the correction frequency to be significantly reduced. This makes it difficult to meet the needs of high-frequency, real-time operation of vehicles and seriously affects the dynamic response capability and long-term accuracy of SOC estimation. Summary of the Invention

[0005] The purpose of this application is to provide a power battery SOC correction method, device, electric vehicle, and storage medium to address the shortcomings of the prior art, thereby solving the technical problems existing in the prior art.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows: In a first aspect, embodiments of this application provide a method for correcting the state of charge (SOC) of a power battery, the method comprising: The charging and discharging current history of the battery under test in this driving cycle is obtained. The charging and discharging current history refers to the recorded sequence of all charging and discharging current changes over time experienced by the battery under test during the entire use process, from the last effective depolarization to the current moment. Based on the charge / discharge current history and the pre-built battery cumulative polarization model, the current polarization degree of the battery under test is determined. Based on the current polarization level and the pre-built pulse depolarization model, the pulse charge / discharge frequency and execution duration of the battery under test are determined. According to the pulse charge / discharge frequency and execution duration, the battery under test is controlled to perform pulse charge / discharge operation, and after the execution is completed, the battery state of charge (SOC) of the battery under test is corrected to obtain the corrected SOC of the battery under test.

[0007] Optionally, the method further includes: Obtain a pre-constructed SOC evaluation model, which includes: a quasi-static SOC evaluation model, a fully charged SOC evaluation model, or a dynamic SOC evaluation model. Using the SOC evaluation model, the corrected SOC of the battery under test is evaluated multiple times to obtain multiple corrected SOC evaluation results. Based on the multiple revised SOC evaluation results, the battery accumulation optimization model was optimized to obtain the optimized battery accumulation optimization model.

[0008] Optionally, determining the current polarization of the battery under test based on the charge / discharge current history includes: Based on the charge and discharge current history, determine the charge and discharge current and temperature values ​​of the battery under test at different times; The charging and discharging current and temperature values ​​at different times are input into the battery cumulative polarization model to calculate the current polarization degree of the battery under test.

[0009] Optionally, determining the pulse charge / discharge frequency and execution duration of the battery under test based on its current polarization and a pre-built pulse depolarization model includes: Based on the current polarization degree of the battery under test, the cumulative polarization result of the battery under test is determined, and the cumulative polarization result includes: charging polarization or discharging polarization; The cumulative polarization result and the current temperature value of the battery under test are input into the pulse depolarization model to determine the discharge frequency and charging frequency of the battery under test. The duration of pulse charge / discharge is determined based on the current polarization of the battery under test.

[0010] Optionally, the execution duration includes the sum of the charging execution duration and the discharging execution duration; The step of determining the execution duration of pulse charging and discharging based on the current polarization of the battery under test includes: If the current polarization degree of the battery under test is less than a preset value, then the sum of the charging execution time and the discharging execution time is determined to be a preset fixed time. If the current polarization of the battery under test is greater than or equal to a preset value, then the sum of the charging execution time and the discharging execution time is determined to be greater than the fixed time.

[0011] Optionally, the processing strategy for the pulse depolarization model includes: The number of pulse charging and discharging times are set within a unit time. If the cumulative polarization result of the battery under test is charging polarization, then the number of discharging times is determined to be greater than the number of charging times; if the cumulative polarization result of the battery under test is discharging polarization, then the number of charging times is determined to be greater than the number of discharging times.

[0012] Optionally, the method further includes: During the pulse charge and discharge operation of the battery under test, the generated noise signal is monitored in real time. When the duration of the noise signal detected exceeds a predetermined duration of a preset noise threshold, a noise exceedance feedback signal is generated. The pulse depolarization model is optimized using the noise excess feedback signal to obtain the optimized pulse depolarization model.

[0013] Secondly, embodiments of this application provide a power battery SOC correction device, the device comprising: The acquisition module is used to acquire the charge and discharge current history of the battery under test in this driving cycle. The charge and discharge current history refers to the recorded sequence of all charge and discharge current changes over time experienced by the battery under test during the entire use process, from the last effective depolarization to the current moment. The determination module is used to determine the current polarization degree of the battery under test based on the charge and discharge current history and a pre-built battery cumulative polarization model; and to determine the pulse charge and discharge frequency and execution duration of the battery under test based on the current polarization degree and a pre-built pulse depolarization model. The control module is used to control the battery under test to perform pulse charging and discharging operations according to the pulse charging and discharging frequency and execution duration; The correction module is used to correct the state of charge (SOC) of the battery under test after execution, so as to obtain the corrected SOC of the battery under test.

[0014] Thirdly, embodiments of this application provide an electric vehicle, which includes a memory for storing one or more programs and a processor. When the one or more programs are executed by the processor, the aforementioned power battery SOC correction method is implemented.

[0015] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the aforementioned power battery SOC correction method.

[0016] The beneficial effects of this application are: This application provides a power battery SOC correction method, device, electric vehicle, and storage medium. Based on a battery cumulative polarization model, the current polarization degree of the battery under test is calculated. Using the current polarization degree and a pre-built pulse depolarization model, the pulse charge-discharge frequency and execution duration of the battery under test are determined. According to the pulse charge-discharge frequency and execution duration of the battery under test, controllable charge-discharge pulses are actively applied to accelerate the elimination of polarization voltage, significantly shorten the depolarization time, and achieve "on-demand real-time correction" without long-term parking waiting. This significantly improves the power battery SOC correction frequency, enhances the system's dynamic response capability to changes in driving conditions, and solves the problem that existing technologies cannot meet the needs of high-frequency, real-time operation of vehicles, which seriously affects the dynamic response capability and long-term accuracy of SOC estimation.

[0017] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A flowchart illustrating a power battery SOC correction method provided in an embodiment of this application; Figure 2 A flowchart illustrating another power battery SOC correction method provided in this application embodiment; Figure 3 A flowchart illustrating another power battery SOC correction method provided in this application embodiment; Figure 4 A flowchart illustrating another power battery SOC correction method provided in this application embodiment; Figure 5 A flowchart illustrating another power battery SOC correction method provided in this application embodiment; Figure 6 A flowchart illustrating another power battery SOC correction method provided in this application embodiment; Figure 7 This is a schematic diagram of the structure of a power battery SOC correction device provided in an embodiment of this application; Figure 8 This is a schematic diagram of the structure of an electric vehicle provided in an embodiment of this application. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0022] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0023] Please see Figure 1 , Figure 1 This is a flowchart illustrating a power battery SOC correction method provided in an embodiment of this application. Optionally, the main execution entity of the power battery SOC correction method can be the main control unit in an electric vehicle. Figure 1 The method includes: S101. Obtain the charge and discharge current history of the battery under test during this driving cycle.

[0024] Among them, the charge and discharge current history refers to the recorded sequence of all charge and discharge current changes over time during the entire use process of the battery under test, from the last effective depolarization to the current moment.

[0025] This driving cycle refers to a continuous process from the end of the last effective depolarization or rest to the current moment, such as a high-speed drive or a short trip.

[0026] In one feasible approach, the charge-discharge current history of the battery under test during the current driving cycle is obtained. The charge-discharge current history can characterize the actual power consumption behavior of the vehicle in the current driving cycle (i.e., the history of current changes). This allows the complex electrochemical process to be transformed into a quantifiable intensity of the "polarization effect" accumulated inside the battery, providing a basis for the subsequent precise application of pulse depolarization.

[0027] S102. Determine the current polarization degree of the battery under test based on the charge / discharge current history and the pre-built battery cumulative polarization model.

[0028] Among them, the battery cumulative polarization model is a mathematical model used to quantify the degree of internal polarization accumulated by a power battery due to its charging and discharging behavior over a period of time. It calculates an index reflecting the current "depolarization demand intensity" of the battery by analyzing the charging and discharging current history.

[0029] Among them, the degree of polarization is used to characterize the degree of battery aging.

[0030] S103. Based on the current polarization level and the pre-built pulse depolarization model, determine the pulse charge / discharge frequency and execution duration of the battery under test.

[0031] Among them, the pulse charge and discharge frequency includes the charging frequency and the discharging frequency. For example, within a fixed time period, the charging frequency is x and the discharging frequency is y. The execution duration refers to the duration of each charge and discharge cycle.

[0032] In one feasible approach, the current polarization level of the battery under test can be calculated using the charge / discharge current history and the battery cumulative polarization model. Then, using the pulse depolarization model and the current polarization level of the battery under test, the pulse charge / discharge frequency and execution duration of the battery under test can be obtained. That is, based on the polarization type of the battery under test (charge polarization / discharge polarization), the ratio of the number of charge / discharge pulses (such as y>x or x>y) can be obtained, thereby achieving directional depolarization and improving the accuracy and energy efficiency of the depolarization process.

[0033] S104. Control the battery under test to perform pulse charging and discharging operations according to the pulse charging and discharging frequency and execution duration. After the execution is completed, correct the battery state of charge (SOC) of the battery under test to obtain the corrected SOC of the battery under test.

[0034] In one feasible approach, the battery under test is controlled to perform pulse charge-discharge operations according to the calculated pulse charge-discharge frequency and execution duration. This involves actively applying controllable charge-discharge pulses to accelerate the elimination of polarization voltage and significantly shorten the depolarization time. After execution, i.e., when the battery depolarization is complete, the battery state of charge (SOC) of the battery under test is corrected using the individual battery cell voltage. This yields the corrected SOC of the battery under test, achieving "on-demand real-time correction" without the need for long-term parking and waiting. This increases the SOC correction frequency, improves the long-term accuracy of SOC, and enhances the system's dynamic response capability to changes in driving conditions.

[0035] In summary, this application provides a power battery SOC correction method. Based on a battery cumulative polarization model, it calculates the current polarization degree of the battery under test. Using the current polarization degree and a pre-built pulse depolarization model, it determines the pulse charge / discharge frequency and execution duration of the battery under test. According to the pulse charge / discharge frequency and execution duration of the battery under test, it actively applies controllable charge / discharge pulses to accelerate the elimination of polarization voltage, significantly shorten the depolarization time, and achieve "on-demand real-time correction." This eliminates the need for long-term parking and waiting, significantly improves the power battery SOC correction frequency, enhances the system's dynamic response capability to changes in driving conditions, and solves the problem in existing technologies that fail to meet the needs of high-frequency, real-time vehicle operation, severely affecting the dynamic response capability and long-term accuracy of SOC estimation.

[0036] Optionally, refer to Figure 2 The diagram shown is a flowchart illustrating another power battery SOC correction method provided in this application. Figure 2 As shown, the method also includes: S201. Obtain the pre-built SOC evaluation model.

[0037] The SOC evaluation models include: quasi-static SOC evaluation model, fully charged SOC evaluation model, or dynamic SOC evaluation model.

[0038] The quasi-static SOC evaluation model is as follows: after the vehicle is quasi-static, the SOC is corrected using the individual cell voltage. The corrected SOC is then compared with the SOC corrected after the previous depolarization to confirm whether the previous corrected SOC was too high or too low.

[0039] The full-charge SOC evaluation model is as follows: the SOC after the battery is fully charged and corrected is compared with the SOC after the previous depolarization correction to confirm whether the previous correction SOC was too high or too low.

[0040] The dynamic SOC evaluation model uses voltage as the core control. When the battery is charged and discharged according to its current power capacity, the voltage of each individual cell is compared with a preset voltage threshold. The voltage threshold is derived from data collected during the functional capability calibration process. Specifically, when the voltage of an individual cell is higher than the preset voltage value, it indicates that the previous SOC correction result was lower than the actual SOC; when the voltage of an individual cell is lower than the preset voltage value, it indicates that the previous SOC correction result was higher than the actual SOC.

[0041] S202. Using the SOC evaluation model, the SOC of the battery under test is evaluated multiple times after correction, and multiple corrected SOC evaluation results are obtained.

[0042] Among them, the corrected SOC evaluation results are used to characterize the direction and degree of deviation of the corrected SOC results.

[0043] S203. Based on the multiple revisions of the SOC evaluation results, the battery accumulation optimization model is optimized to obtain the optimized battery accumulation optimization model.

[0044] Optionally, during the entire life cycle of a power battery, its polarization characteristics exhibit a time-varying and nonlinear evolution trend due to material aging, internal resistance increase, and capacity decay. Existing depolarization control strategies are mostly based on fixed parameters or empirical models, lacking online perception of battery aging status and the ability to adaptively adjust the model. This leads to a gradual deterioration in the control effect of the depolarization process over time, making it impossible to achieve continuous optimization control throughout the entire life cycle. Therefore, in this embodiment, a SOC evaluation model (quasi-static evaluation model, full-charge evaluation model, and dynamic evaluation model) is introduced. The quasi-static SOC evaluation model, full-charge SOC evaluation model, or dynamic SOC evaluation model are used to evaluate the corrected SOC of the battery under test multiple times, obtaining multiple corrected SOC evaluation results. Then, the multiple corrected SOC evaluation results are summarized and aggregated. When the accumulated multiple evaluation results show that the pulse SOC correction has a deviation greater than a preset value A%, a feedback process is initiated. The SOC correction deviation is fed back to the battery cumulative polarization model to optimize model parameters such as the polarization coefficient σ in the battery cumulative polarization model. This enables the battery cumulative polarization model to achieve online self-learning and adaptive adjustment, ensuring high-precision estimation throughout the battery's entire lifespan and improving the long-term accuracy and lifespan adaptability of SOC estimation.

[0045] Optionally, refer to Figure 3 The diagram shown is a flowchart illustrating another power battery SOC correction method provided in this application. Figure 3 As shown, step S102 above includes: S301. Based on the charge and discharge current history, determine the charge and discharge current and temperature values ​​of the battery under test at different times.

[0046] S302. Input the charging and discharging current and temperature values ​​at different times into the battery cumulative polarization model to calculate the current polarization degree of the battery under test.

[0047] The degree of polarization is mainly affected by two dimensions: current and temperature.

[0048] In one feasible approach, the charging and discharging current and temperature values ​​of the battery under test at different times are obtained. For example, the current I1 and temperature T1 at time t1 are recorded, and the current I2 and temperature T2 at time t2 are recorded. Then, the current polarization degree of the battery under test can be calculated using the battery cumulative polarization model as shown in the following formula (1): i=σ1(I1,T1)+σ2(I2,T2)+……+σn(In,Tn) (1) Where i represents the degree of polarization and σ represents the polarization coefficient. The initial calibration is performed based on cell-level testing, and different currents and temperatures correspond to different σ values.

[0049] Optionally, refer to Figure 4 The diagram shown is a flowchart illustrating another power battery SOC correction method provided in this application. Figure 4 As shown, step S103 above includes: S401. Determine the cumulative polarization result of the battery under test based on the current polarization degree of the battery under test.

[0050] Among them, cumulative polarization results include: charging polarization or discharging polarization.

[0051] S402. Based on the cumulative polarization result of the battery under test and the current temperature value, input them into the pulse depolarization model to determine the discharge frequency and charging frequency of the battery under test.

[0052] S403. Determine the execution duration of pulse charging and discharging based on the current polarization degree of the battery under test.

[0053] In one feasible approach, the current polarization level of the battery under test is used to determine whether the cumulative polarization result of the battery under test is charging polarization or discharging polarization. Then, the cumulative polarization result of the battery under test and the current temperature value are input into the pulse depolarization model to calculate the discharge frequency, charging frequency x, and discharge frequency y of the battery under test. Based on the current polarization level of the battery under test, the execution duration of pulse charging and discharging is determined. That is, according to the polarization state of the battery under test, the frequency of pulse charging and discharging is adjusted to achieve battery depolarization under both charging polarization and discharging polarization conditions, thereby achieving the purpose of directional depolarization, improving pulse energy utilization efficiency, avoiding ineffective or reverse excitation, and improving the accuracy and energy efficiency ratio of the depolarization process.

[0054] Optionally, the execution duration includes the sum of the charging execution duration and the discharging execution duration; refer to Figure 5 The diagram shown is a flowchart illustrating another power battery SOC correction method provided in this application. Figure 5 As shown, step S103 above includes: S501. If the current polarization degree of the battery under test is less than the preset value, then the sum of the charging execution time and the discharging execution time is determined to be the preset fixed time.

[0055] In one feasible approach, if the current polarization of the battery under test is detected to be less than a preset value, it indicates that the current polarization of the battery under test is low, which means that its electrochemical response is good, its internal resistance is low, and its kinetic performance is superior. Therefore, a standard, fixed test cycle (e.g., 1 hour of charging + 1 hour of discharging = 2 hours in total) can be used to complete the effective evaluation, that is, to determine that the sum of the charging execution time and the discharging execution time is a preset fixed time.

[0056] S502. If the current polarization degree of the battery under test is greater than or equal to the preset value, then the sum of the charging execution time and the discharging execution time is determined to be greater than the fixed time.

[0057] In another feasible approach, if the current polarization of the battery under test is detected to be greater than or equal to a preset value, it indicates severe polarization, suggesting potential issues such as aging, interface deterioration, or electrolyte drying. In this case, the total charge-discharge test time needs to be extended to more fully stimulate its dynamic response behavior, thereby obtaining more refined aging characteristics, such as slow voltage relaxation processes and diffusion limitation effects. This means ensuring that the sum of the charging and discharging execution times is greater than a fixed duration. Therefore, the sum of the charging and discharging execution times is not constant but increases with the intensification of polarization, thus meeting the requirements of adaptive testing.

[0058] Optionally, the processing strategies for the pulse depolarization model include: The number of pulse charging and discharging times are set within a unit of time. If the cumulative polarization result of the battery under test is charging polarization, then the number of discharging times is greater than the number of charging times; if the cumulative polarization result of the battery under test is discharging polarization, then the number of charging times is greater than the number of discharging times.

[0059] In one feasible approach, the number of pulse charging and discharging pulses is set within a unit time. For example, within 1 minute, a cycle of "charging for 5 seconds → stopping for 2 seconds → charging for 5 seconds → stopping for 2 seconds" is executed, for a total of 3 complete cycles, meaning the charging frequency is 3 times and the discharging frequency is 3 times. If the cumulative polarization result of the battery under test is detected as charging polarization, indicating that the battery is in a state of "easy lithium plating" and "high negative electrode pressure" for a long time, then it is determined that the number of discharging pulses is greater than the number of charging pulses within a unit time. For example, within 1 minute, 4 discharging pulses and 2 charging pulses are executed to reduce charging excitation and enhance the discharging process to alleviate negative electrode overload.

[0060] In another feasible approach, if the cumulative positive polarization result of the battery under test is identified as discharge polarization, it indicates that the battery often experiences deep discharge and the risk of damage to the positive electrode is high. In this case, it is determined that the number of charging times per unit time is greater than the number of discharging times. For example, within 1 minute, 4 charging pulses and 2 discharging pulses are executed to reduce the discharge frequency and increase the charging excitation to activate the positive electrode.

[0061] Optionally, refer to Figure 6 The diagram shown is a flowchart illustrating another power battery SOC correction method provided in this application. Figure 6 As shown, the method includes: S601. During the pulse charge and discharge operation of the battery under test, the generated noise signal is monitored in real time.

[0062] S602. When the duration of the noise signal detected exceeds the preset noise threshold, a noise exceedance feedback signal is generated.

[0063] S603. Using the noise exceeding the standard feedback signal, the pulse depolarization model is optimized to obtain the optimized pulse depolarization model.

[0064] Optionally, during accelerated depolarization or SOC correction using pulsed charging and discharging, significant electromagnetic noise and mechanical vibration are often present. This is especially true under conditions of accelerated aging and uneven internal stress distribution, where the thermo-electro-mechanical coupling effect induced by the pulsed current further amplifies the noise level. High noise not only affects passenger comfort but may also interfere with the normal operation of in-vehicle electronic equipment. Current technologies lack real-time monitoring and feedback adjustment mechanisms for noise during the pulsed process, making it difficult to effectively suppress noise pollution while improving depolarization efficiency, thus hindering the widespread application of pulsed technology in in-vehicle environments.

[0065] Therefore, in this embodiment, in order to optimize the pulse depolarization model, it is proposed to monitor the generated noise signal in real time during the pulse charge and discharge operation of the battery under test. When the duration of the noise signal exceeds the predetermined duration of the preset noise threshold B dB, a noise exceedance feedback signal is generated. The pulse depolarization model is then optimized using the noise exceedance feedback signal to obtain the optimized pulse depolarization model. This dynamically adjusts the pulse charge and discharge operation frequency, reduces the number of charge and discharge pulses per unit time, weakens the polarization effect, suppresses noise, and improves the user experience.

[0066] In summary, this application provides a power battery SOC correction method that can balance depolarization efficiency, model adaptability, and noise control, achieving efficient, quiet, and reliable SOC state correction of new energy vehicle power batteries throughout their entire life cycle, improving the SOC correction probability and effectively enhancing long-term SOC accuracy. The SOC evaluation model feedback mechanism improves the iterative optimization of power battery parameters throughout their entire life cycle; the noise evaluation model feedback mechanism enhances the stability of the system during long-term use, effectively balancing user experience and the adverse effects of performance degradation after device aging.

[0067] Optionally, refer to Figure 7The diagram shown is a structural schematic of a power battery SOC correction device provided in this application. Figure 7 As shown, the device includes: The acquisition module 701 is used to acquire the charge and discharge current history of the battery under test in this driving cycle. The charge and discharge current history refers to the recorded sequence of all charge and discharge current changes over time experienced by the battery under test during the entire use process, from the last effective depolarization to the current moment. The determination module 702 is used to determine the current polarization degree of the battery under test based on the charge and discharge current history and a pre-built battery cumulative polarization model; and to determine the pulse charge and discharge frequency and execution duration of the battery under test based on the current polarization degree and a pre-built pulse depolarization model. Control module 703 is used to control the battery under test to perform pulse charging and discharging operations according to the pulse charging and discharging frequency and execution duration; The correction module 704 is used to correct the state of charge (SOC) of the battery under test after execution, so as to obtain the corrected SOC of the battery under test.

[0068] Optionally, the acquisition module 701 is also used for: Obtain a pre-constructed SOC evaluation model, which includes: a quasi-static SOC evaluation model, a fully charged SOC evaluation model, or a dynamic SOC evaluation model. The device also includes: The evaluation module is used to evaluate the corrected SOC of the battery under test multiple times using the SOC evaluation model, and obtain multiple corrected SOC evaluation results. The optimization module is used to optimize the battery accumulation optimization model based on the multiple revised SOC evaluation results, so as to obtain the optimized battery accumulation optimization model.

[0069] Optionally, module 702 is specifically used for: Based on the charge and discharge current history, determine the charge and discharge current and temperature values ​​of the battery under test at different times; The charging and discharging current and temperature values ​​at different times are input into the battery cumulative polarization model to calculate the current polarization degree of the battery under test.

[0070] Optionally, module 702 is specifically used for: Based on the current polarization degree of the battery under test, the cumulative polarization result of the battery under test is determined, and the cumulative polarization result includes: charging polarization or discharging polarization; The cumulative polarization result and the current temperature value of the battery under test are input into the pulse depolarization model to determine the discharge frequency and charging frequency of the battery under test. The duration of pulse charge / discharge is determined based on the current polarization of the battery under test.

[0071] Optionally, the execution duration includes the sum of the charging execution duration and the discharging execution duration; the determining module 702 is specifically used for: If the current polarization degree of the battery under test is less than a preset value, then the sum of the charging execution time and the discharging execution time is determined to be a preset fixed time. If the current polarization of the battery under test is greater than or equal to a preset value, then the sum of the charging execution time and the discharging execution time is determined to be greater than the fixed time.

[0072] Optionally, the processing strategy for the pulse depolarization model includes: The number of pulse charging and discharging times are set within a unit time. If the cumulative polarization result of the battery under test is charging polarization, then the number of discharging times is determined to be greater than the number of charging times; if the cumulative polarization result of the battery under test is discharging polarization, then the number of charging times is determined to be greater than the number of discharging times.

[0073] Optionally, the device further includes: The monitoring module is used to monitor the noise signal generated in real time during the pulse charge and discharge operation of the battery under test; The generation module is used to generate a noise exceedance feedback signal when the duration of the detected noise signal exceeds a predetermined duration of a preset noise threshold. The optimization module is used to optimize the pulse depolarization model using the noise excess feedback signal to obtain the optimized pulse depolarization model.

[0074] Optionally, refer to Figure 8 The diagram shown is a structural schematic of an electric vehicle provided in this application, which can integrate a main control unit with data processing capabilities.

[0075] The electric vehicle includes: processor 801 and memory 802.

[0076] The memory 802 is used to store programs, and the processor 801 calls the programs stored in the memory 802 to execute the above method embodiments. The specific implementation and technical effects are similar, and will not be described again here.

[0077] Optionally, this application also provides a program product, such as a computer-readable storage medium, including a program that, when executed by a processor, performs the above-described method embodiments.

[0078] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0079] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0080] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in a combination of hardware and software functional units.

[0081] The integrated units implemented as software functional units described above can be stored in a computer-readable storage medium. These software functional units, stored in a storage medium, include several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute some steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0082] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

[0083] It will be apparent to those skilled in the art that this application is not limited to the details of the exemplary embodiments described above, and that this application can be implemented in other specific forms without departing from the spirit or essential characteristics of this application. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this application is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this application. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for correcting the SOC of a power battery, characterized in that, The method comprises: obtaining the charge-discharge current history of the battery to be tested in the current driving cycle, wherein the charge-discharge current history refers to the record sequence of all the charge-discharge currents experienced by the battery to be tested in the whole use process from the last effective depolarization to the current time; determining the current polarization degree of the battery to be tested according to the charge-discharge current history and the pre-constructed battery cumulative polarization model; determining the pulse charge-discharge frequency and execution duration of the battery to be tested according to the current polarization degree and the pre-constructed pulse depolarization model; controlling the battery to be tested to perform pulse charge-discharge operation according to the pulse charge-discharge frequency and execution duration, and performing battery state of charge (SOC) correction on the battery to be tested after the execution ends to obtain the corrected SOC of the battery to be tested.

2. The method of claim 1, wherein, The method further comprises: obtaining a pre-constructed SOC evaluation model, wherein the SOC evaluation model comprises a quasi-static SOC evaluation model, a full-charge SOC evaluation model or a dynamic SOC evaluation model; evaluating the corrected SOC of the battery to be tested multiple times using the SOC evaluation model to obtain multiple corrected SOC evaluation results; optimizing the battery cumulative polarization model according to the multiple corrected SOC evaluation results to obtain an optimized battery cumulative polarization model.

3. The method of claim 1, wherein, The determination of the current polarization degree of the battery to be tested according to the charge-discharge current history comprises: determining the charge-discharge current and temperature value of the battery to be tested at different times according to the charge-discharge current history; inputting the charge-discharge current and temperature value at different times into the battery cumulative polarization model to calculate the current polarization degree of the battery to be tested.

4. The method of claim 1, wherein, The determination of the pulse charge-discharge frequency and execution duration of the battery to be tested according to the current polarization degree of the battery to be tested and the pre-constructed pulse depolarization model comprises: determining the cumulative polarization result of the battery to be tested according to the current polarization degree of the battery to be tested, wherein the cumulative polarization result comprises charge polarization or discharge polarization; determining the discharge frequency and charge frequency of the battery to be tested according to the cumulative polarization result of the battery to be tested and the current temperature value input into the pulse depolarization model; determining the execution duration of pulse charge-discharge according to the current polarization degree of the battery to be tested.

5. The method of claim 4, wherein, The execution duration comprises the sum of the charge execution duration and the discharge execution duration. The determination of the execution duration of pulse charge-discharge according to the current polarization degree of the battery to be tested comprises: if the current polarization degree of the battery to be tested is less than a preset value, determining that the sum of the charge execution duration and the discharge execution duration is a pre-set fixed duration; if the current polarization degree of the battery to be tested is greater than or equal to the preset value, determining that the sum of the charge execution duration and the discharge execution duration is greater than the fixed duration.

6. The method of claim 4, wherein, The processing strategy of the pulse depolarization model comprises: The number of pulse charging times and the number of pulse discharging times are set in a unit time, if the cumulative polarization result of the battery to be tested is charging polarization, it is determined that the number of discharging times is greater than the number of charging times; if the cumulative polarization result of the battery to be tested is discharging polarization, it is determined that the number of charging times is greater than the number of discharging times.

7. The method of claim 1, wherein, The method further comprises: In the process of performing the pulse charging and discharging operation on the battery to be tested, the generated noise signal is monitored in real time; When the duration of the noise signal monitored exceeds the predetermined duration of the preset noise threshold, a noise exceeding standard feedback signal is generated; The noise exceeding standard feedback signal is used to optimize the pulse depolarization model to obtain an optimized pulse depolarization model.

8. A power battery SOC correction device, characterized in that, The device comprises: An acquisition module is configured to acquire a charging and discharging current history of a battery to be tested in a current driving cycle, the charging and discharging current history being a record sequence of all charging and discharging currents experienced by the battery to be tested over time from the beginning of the last effective depolarization to the current time; A determination module is configured to determine a current polarization degree of the battery to be tested according to the charging and discharging current history and a battery cumulative polarization model constructed in advance, and determine a pulse charging and discharging frequency and execution duration of the battery to be tested according to the current polarization degree and a pulse depolarization model constructed in advance; A control module is configured to control the battery to be tested to perform a pulse charging and discharging operation according to the pulse charging and discharging frequency and execution duration; A correction module is configured to correct a state of charge (SOC) of the battery to be tested after the execution to obtain a corrected SOC of the battery to be tested.

9. An electric vehicle, characterized by It comprises: A processor, a storage medium and a bus, the storage medium stores machine readable instructions executable by the processor, when the electric vehicle is running, the processor and the storage medium communicate through the bus, the processor executes the machine readable instructions to perform the steps of the method of any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which is executed by the processor when running to perform the method of any one of claims 1-7.

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