Battery SOC Calibration Method, System, Storage Medium and Terminal

Abstract

The present invention provides a battery SOC calibration method, system, storage medium and terminal. The method includes the following steps: obtaining the voltage and cumulative charge capacity during battery charging at a preset time interval; constructing a correlation curve between the cumulative charge capacity and the voltage; obtaining the inflection point of the correlation curve when the battery is close to full charge, and constructing a fitting curve between the cumulative charge capacity and the voltage from the inflection point to the end of charging based on the correlation curve; extending the fitting curve to obtain an extension line, and determining the point on the extension line where the voltage is the maximum voltage value of the battery; calculating the calibrated SOC corresponding to the charging time n. The battery SOC calibration method, system, storage medium and terminal of the present invention are based on the fitting of battery charging data to effectively calibrate the battery SOC.

Description

Technical Field

[0001] The present invention relates to the technical field of the State of Charge (SOC) of batteries, and particularly to a method, a system, a storage medium, and a terminal for calibrating the SOC of a battery. Background Art

[0002] With the rapid development of the new energy field, lithium batteries have become the preferred energy source for new energy vehicles and energy storage power stations due to their high energy density, long cycle life, and other characteristics.

[0003] SOC is the ratio of the remaining capacity of a storage battery after being used for a period of time or left unused for a long time to its capacity in a fully charged state, usually expressed as a percentage, and its value range is 0 to 1. When SOC = 0, it means the battery is completely discharged; when SOC = 1, it means the battery is fully charged. The SOC of the battery determines how much power the device has left, whether it is sufficient to continue normal operation, and whether it needs to be charged. Therefore, accurately estimating the SOC of the battery is of great significance.

[0004] In the prior art, methods such as the ampere-hour integration method and the Kalman filtering method are usually used for estimating the SOC of the battery. However, there will be certain errors in predicting the SOC by the above methods, especially when approaching full charge or full discharge, the SOC error will be greater. Summary of the Invention

[0005] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a method, a system, a storage medium, and a terminal for calibrating the SOC of a battery, which can effectively calibrate the SOC of the battery based on the fitting of the charging data of the battery.

[0006] In a first aspect, the present invention provides a method for calibrating the SOC of a battery, the method comprising the following steps: obtaining the voltage and the cumulative charge capacity during battery charging at a preset time interval; constructing a correlation curve between the cumulative charge capacity and the voltage; obtaining an inflection point of the correlation curve when the battery is close to full charge, and constructing a fitting curve between the cumulative charge capacity and the voltage from the inflection point to the end point of charging based on the correlation curve; extending the fitting curve to obtain an extension line, and determining a point on the extension line where the voltage is the maximum voltage value of the battery; according to calculating the calibrated SOC corresponding to the charging time n, where represents the reverse cumulative charge capacity from the end point of charging to the charging time n, Q cap represents the rated capacity of the battery, represents the calibrated SOC corresponding to the end point of charging.

[0007] In an implementation manner of the first aspect, it further includes according to calculating the calibrated SOC corresponding to the end point of charging, where represents the cumulative charge capacity corresponding to the point on the extension line where the voltage is the maximum battery voltage value, represents the cumulative charge capacity corresponding to the charge end point on the fitting curve.

[0008] In one implementation manner of the first aspect, the cumulative charge capacity during battery charging is obtained by any of the following methods:

[0009] Obtain the current during battery charging, and obtain the cumulative charge capacity based on the ampere-hour integration method;

[0010] Obtain the current during battery charging, and obtain the cumulative charge capacity based on the Kalman filtering method;

[0011] Measure the cumulative charge capacity using an instrument.

[0012] In one implementation manner of the first aspect, the fitting curve is Q j = m1×U j + m0, where both m1 and m0 represent the coefficients of the linear equation, and where U j represents the voltage at the j-th moment, and Q j represents the cumulative charge capacity charged to the j-th moment.

[0013] In one implementation manner of the first aspect, is set to 1.

[0014] In one implementation manner of the first aspect, it further includes comparing the calibrated SOC and the measured SOC, and analyzing the error of the measured SOC.

[0015] In one implementation manner of the first aspect, it further includes when the battery starts to discharge, using the calibrated SOC corresponding to the charge end point as the initial SOC for discharge.

[0016] In a second aspect, the present invention provides a battery SOC calibration system, including an acquisition module, a construction module, a fitting module, an extension module, and a calibration module;

[0017] The acquisition module is used to acquire the voltage and cumulative charge capacity during battery charging at a preset time interval;

[0018] The construction module is used to construct the correlation curve between the cumulative charge capacity and the voltage;

[0019] The fitting module is used to obtain the inflection point of the correlation curve when the battery is close to full charge, and construct the fitting curve between the cumulative charge capacity and the voltage between the inflection point and the charge end point based on the correlation curve;

[0020] The extension module is used to extend the fitted curve to obtain an extension line, and determine the point on the extension line where the voltage is the maximum battery voltage value;

[0021] The calibration module is used to calculate the calibrated SOC corresponding to the charging time n, where represents the reverse cumulative charge capacity between the end point of charging and the charging time n, and Q cap represents the rated capacity of the battery, represents the calibrated SOC corresponding to the end point of charging.

[0022] In a third aspect, the present invention provides a storage medium, on which a computer program is stored, and when the program is executed by a processor, the above-mentioned battery SOC calibration method is implemented.

[0023] In a fourth aspect, the present invention provides a battery SOC calibration terminal, including: a processor and a memory;

[0024] The memory is used to store a computer program;

[0025] The processor is used to execute the computer program stored in the memory, so that the battery SOC calibration terminal executes the above-mentioned battery SOC calibration method.

[0026] As described above, the battery SOC calibration method, system, storage medium and terminal of the present invention have the following beneficial effects:

[0027] (1) The calibration of the battery SOC is realized by the relationship between the voltage and the cumulative capacity during battery charging, and the accuracy is high;

[0028] (2) No additional test conditions and equipment are required, and only the sampled data of the battery is relied on, which greatly increases the application scenarios and scope, and has strong practicability;

[0029] (3) It can be applied to each charging process of the battery to ensure that the SOC is still accurate during multiple charge and discharge cycles, and it does not require the battery to start charging from a zero state of charge. The SOC calibration can be carried out when the battery state of charge is 20% or 30%;

[0030] (4) As the battery is used, the internal resistance of the battery increases due to aging, resulting in an increase in the battery voltage. Therefore, the highest voltage after the aged battery is fully charged must be greater than the maximum single-cell voltage U max specified in the specification. The present invention requires that the battery SOC be 100% when the battery voltage is U max , so that when the voltage of the aged battery exceeds U max , charging should no longer be carried out, thus protecting the battery. Description of the Drawings

[0031] Figure 1 Shown is a flowchart of the battery SOC calibration method of the present invention in an embodiment;

[0032] Figure 2 Shown is a schematic diagram of the cumulative capacity and voltage of a battery changing with time during charging in an embodiment;

[0033] Figure 3 Shown is a fitting graph of the cumulative capacity and voltage of a battery changing with time during charging in an embodiment;

[0034] Figure 4 Shown is a comparison schematic diagram of the SOC correction value and the SOC measurement value obtained by the battery SOC calibration method of the present invention in an embodiment;

[0035] Figure 5 Shown is a schematic structural diagram of the battery SOC calibration system of the present invention in an embodiment;

[0036] Figure 6 Shown is a schematic structural diagram of the battery SOC calibration terminal of the present invention in an embodiment.

[0037] Description of component numbers

[0038] 51 Acquisition module

[0039] 52 Construction module

[0040] 53 Fitting module

[0041] 54 Extension module

[0042] 55 Calibration module

[0043] 61 Processor

[0044] 62 Memory Detailed implementation manners

[0045] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0046] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0047] In actual application scenarios, batteries are always charged from a certain lower capacity to full charge or nearly full charge. The battery SOC calibration method, system, storage medium, and terminal of the present invention achieve SOC calibration based on the fitting of battery charging data, thereby greatly expanding the application scenarios and scope. It should be noted that the discharge data of the battery is not used because in most real scenarios, to ensure battery safety, the battery is basically not fully discharged or nearly fully discharged during use, resulting in a relatively large error in the fitting result.

[0048] As Figure 1 shown, in one embodiment, the battery SOC calibration method of the present invention includes the following steps:

[0049] Step S1: Obtain the voltage and cumulative charge capacity of the battery during charging at a preset time interval.

[0050] Specifically, when the battery is in the charging state, information such as the voltage, current, SOC, and temperature of the battery is collected at every preset time interval; at the same time, the cumulative charge capacity of the battery from the charging moment is obtained. For example, the cumulative charge capacity corresponding to the jth sampling can be expressed as where Δt k is the time interval between the kth and (k - 1)th samplings, i k is the current at the kth sampling, and i k-1 is the current at the (k - 1)th sampling, where k ≤ j.

[0051] In one embodiment of the present invention, the cumulative charge capacity of the battery during charging is obtained by any of the following methods:

[0052] 11) Obtain the current of the battery during charging, and obtain the cumulative charge capacity based on the ampere-hour integration method.

[0053] 12) Obtain the current of the battery during charging, and obtain the cumulative charge capacity based on the Kalman filtering method;

[0054] 13) Measure the cumulative charge capacity using an instrument.

[0055] Step S2: Construct the correlation curve between the cumulative charge capacity and the voltage.

[0056] Specifically, as Figure 2As shown, with the cumulative charge capacity as the horizontal axis and the voltage as the vertical axis, an association curve between the two is constructed based on the acquired cumulative charge capacity and voltage, where point P2 represents the end point of charging.

[0057] Step S3: Obtain the inflection point of the association curve when the battery is approaching full charge, and construct a fitting curve of the cumulative charge capacity and voltage between the inflection point and the end point of charging based on the association curve.

[0058] Specifically, from Figure 2 it can be seen that when the battery is approaching full charge, the association curve has an inflection point P1 when the voltage is around 4.00V. On the association curve, starting from the inflection point and ending at the end point of charging, a linear fit is performed to obtain the fitting curve Q j = m1×U j + m0, where both m1 and m0 represent the coefficients of the linear equation, where U j represents the voltage at time j, and Q j represents the cumulative charge capacity when charging to time j. Preferably, the goodness of fit is 0.9947.

[0059] Step S4: Extend the fitting curve to obtain an extension line, and determine the point on the extension line where the voltage is the maximum voltage value of the battery.

[0060] Specifically, as Figure 3 shown, extend the fitting curve along the direction of increasing horizontal axis until the fitting curve intersects the straight line where the maximum voltage of the single battery required by the battery specification book is located at point P3. Preferably, the SOC corresponding to P3 is 100%, indicating that the battery is fully charged.

[0061] Step S5: Calculate the calibrated SOC corresponding to the charging time n according to , where represents the reverse cumulative charge capacity between the end point of charging and the charging time n, Q cap represents the rated capacity of the battery, represents the calibrated SOC corresponding to the end point of charging.

[0062] Specifically, first calculate the calibrated SOC corresponding to the end point of charging according to , where represents the cumulative charge capacity corresponding to the point on the extension line where the voltage is the maximum voltage value of the battery, represents the cumulative charge capacity corresponding to the end point of charging on the fitting curve.

[0063] Then, based on the reverse ampere-hour integration method, calculate the reverse cumulative charge capacity from the end of charging to the charging time n It should be noted that during the entire charging sampling process, the last sampling (i.e., the end-th sampling) is used as the starting point for the reverse ampere-hour integration calculation to calculate the corresponding reverse cumulative capacity at the actual n-th sampling. Among them, Δt k is the time interval between the k-th and (k - 1)-th reverse samplings, and i k is the current at the k-th reverse sampling. represents the reverse cumulative capacity calculated by the reverse ampere-hour integration from the end point of charging to the n-th sampling, where end ≥ k ≥ n.

[0064] Therefore, after the calculation is completed the calibrated SOC corresponding to the charging time n is

[0065] In an embodiment of the present invention, the battery SOC calibration method of the present invention further includes comparing the calibrated SOC and the measured SOC, analyzing the error of the measured SOC, so as to judge whether the measured SOC is too large or too small, providing a direction for more accurate estimation of SOC. As Figure 4 shown, in most stages of charging, the difference between the measured SOC and the calibrated SOC is not large and they almost coincide. However, when the battery is close to full charge, the error of the measured SOC gradually increases, being about 2.5% larger than the calibrated SOC. If the measured SOC is not calibrated, the battery cannot be fully charged, resulting in the inability to fully utilize the battery energy, and at the same time, over-discharge may occur during discharge.

[0066] When the battery starts to discharge, the calibrated SOC corresponding to the end point of charging is used as the initial SOC of discharge to ensure that the SOC of the battery during discharge is more accurate. At the next charging after the discharge ends, the battery SOC calibration method of the present invention is still followed, so as to ensure that the SOC still has high accuracy during the charge and discharge cycles of the battery.

[0067] The protection scope of the battery SOC calibration method described in the embodiments of the present invention is not limited to the execution order of the steps listed in this embodiment. Any solution achieved by adding or subtracting steps of the prior art and replacing steps according to the principle of the present invention is included in the protection scope of the present invention.

[0068] The embodiments of the present invention also provide a battery SOC calibration system. The battery SOC calibration system can implement the battery SOC calibration method described in the present invention. However, the implementation devices of the battery SOC calibration system described in the present invention include but are not limited to the structures of the battery SOC calibration system listed in this embodiment. Any structural deformation and replacement of the prior art made according to the principle of the present invention are included in the protection scope of the present invention.

[0069] As Figure 5As shown, in one embodiment, the battery SOC calibration system of the present invention includes an acquisition module 51, a construction module 52, a fitting module 53, an extension module 54, and a calibration module 55.

[0070] The acquisition module 51 is used to acquire the voltage and cumulative charge capacity of the battery during charging at a preset time interval.

[0071] Specifically, when the battery is in the charging state, information such as the voltage, current, SOC, and temperature of the battery is collected at every preset time interval; meanwhile, the cumulative charge capacity of the battery from the charging moment is acquired. For example, the cumulative charge capacity corresponding to the jth sampling can be expressed as where Δt k is the time interval between the kth and (k - 1)th samplings, and i k is the current at the kth sampling, and i k-1 is the current at the (k - 1)th sampling, where k ≤ j.

[0072] In one embodiment of the present invention, the cumulative charge capacity of the battery during charging is acquired by any of the following methods:

[0073] 11) Acquire the current of the battery during charging, and acquire the cumulative charge capacity based on the ampere-hour integration method.

[0074] 12) Acquire the current of the battery during charging, and acquire the cumulative charge capacity based on the Kalman filtering method;

[0075] 13) Measure the cumulative charge capacity with an instrument.

[0076] The construction module 52 is connected to the acquisition module 51 and is used to construct the correlation curve between the cumulative charge capacity and the voltage.

[0077] Specifically, as Figure 2 shown, with the cumulative charge capacity as the horizontal axis and the voltage as the vertical axis, the correlation curve between the two is constructed based on the acquired cumulative charge capacity and voltage, where point P2 represents the end point of charging.

[0078] The fitting module 53 is connected to the construction module 52 and is used to acquire the inflection point of the correlation curve when the battery is close to full charge, and construct the fitting curve of the cumulative charge capacity and voltage between the inflection point and the end point of charging based on the correlation curve.

[0079] Specifically, as can be seen from Figure 2 , when the battery is close to full charge, the correlation curve has an inflection point P1 when the voltage is around 4.00V. On the correlation curve, starting from the inflection point and ending at the end point of charging, a linear fitting is performed to obtain the fitting curve Q j = m1×U j+m0, where both m1 and m0 represent the coefficients of a linear equation, where U j represents the voltage at time j, and represents Q j the cumulative charge capacity charged up to time j. Preferably, the goodness of fit is 0.9947.

[0080] The extension module 54 is connected to the fitting module 53 and is used to extend the fitting curve to obtain an extension line and determine the point on the extension line where the voltage is the maximum voltage value of the battery.

[0081] Specifically, as Figure 3 shown, extend the fitting curve along the direction of increasing horizontal axis until the fitting curve intersects the straight line where the maximum voltage of the single battery required by the battery specification book at point P3. Preferably, the SOC corresponding to P3 is 100%, indicating that the battery is fully charged.

[0082] The calibration module 55 is connected to the extension module 54 and is used for

[0083] According to calculate the calibrated SOC corresponding to the charging time n, where represents the reverse cumulative charge capacity between the end point of charging and the charging time n, Q cap represents the rated capacity of the battery, represents the calibrated SOC corresponding to the end point of charging.

[0084] Specifically, first according to calculate the calibrated SOC corresponding to the end point of charging, where represents the cumulative charge capacity corresponding to the point on the extension line where the voltage is the maximum voltage value of the battery, represents the cumulative charge capacity corresponding to the end point of charging on the fitting curve.

[0085] Then, based on the reverse ampere-hour integration method, calculate the reverse cumulative charge capacity from the end of charging to the charging time n It should be noted that during the entire charging sampling process, the last sampling (i.e., the end-th sampling) is used as the starting point for reverse ampere-hour integration calculation to calculate the reverse cumulative capacity corresponding to the actual n-th sampling. Among them, Δt k is the time interval between the k-th and (k - 1)-th reverse samplings, i k is the current at the k-th reverse sampling, represents the reverse cumulative capacity calculated by reverse ampere-hour integration from the end point of charging to the n-th sampling, where end ≥ k ≥ n.

[0086] Therefore, after the calculation is completed the calibrated SOC corresponding to the charging time n is

[0087] In an embodiment of the present invention, the battery SOC calibration system of the present invention further includes a comparison module, which is used to compare the calibrated SOC and the measured SOC, analyze the error of the measured SOC, so as to judge whether the measured SOC is too large or too small, and provide a direction for more accurate estimation of SOC. As Figure 4 shown, in most stages of charging, the difference between the measured SOC and the calibrated SOC is not large and they almost coincide. However, when the battery is close to full charge, the error of the measured SOC gradually increases, and it is about 2.5% larger than the calibrated SOC. If the measured SOC is not calibrated, the battery cannot be fully charged, resulting in insufficient utilization of battery energy, and over-discharge may occur during discharge.

[0088] When the battery discharges, the calibrated SOC corresponding to the end point of charging is used as the initial SOC of discharge to ensure that the SOC of the battery during discharge is more accurate. During the next charging after discharge, the battery SOC calibration method of the present invention is still followed, so as to ensure that the SOC still has high accuracy with the charge and discharge cycles of the battery.

[0089] It should be noted that the division of each module of the above device is only a division of logical functions. In actual implementation, it can be fully or partially integrated into a physical entity, or physically separated. And these modules can all be implemented in the form of software called by a processing element, or all be implemented in the form of hardware, or some modules be implemented in the form of software called by a processing element and some modules be implemented in the form of hardware. For example, the x module can be a separately established processing element, or be integrated in a certain chip of the above device. In addition, the x module can also be stored in the memory of the above device in the form of program code, and the function of the above x module can be called and executed by a certain processing element of the above device. The implementation of other modules is similar. These modules can be fully or partially integrated together, or can be independently implemented. The processing element mentioned here can be an integrated circuit with the ability to process signals. In the implementation process, each step of the above method or each of the above modules can be completed by the integrated logic circuit in the processor element or the instructions in the form of software. The above modules can be one or more integrated circuits configured to implement the above method, for example: one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Field Programmable Gate Arrays (FPGAs), etc. When a certain module above is implemented in the form of a program code scheduled by a processing element, the processing element can be a general-purpose processor, such as a Central Processing Unit (CPU) or other processors that can call program code. These modules can be integrated together and implemented in the form of a System-on-a-chip (SOC).

[0090] A computer program is stored on the storage medium of the present invention, and when the program is executed by a processor, the above battery SOC calibration method is implemented. Preferably, the storage medium includes: various media such as ROM, RAM, magnetic disk, USB flash drive, memory card or optical disc that can store program code.

[0091] As Figure 6 shown, in an embodiment, the battery SOC calibration terminal of the present invention includes: a processor 61 and a memory 62.

[0092] The memory 62 is used to store a computer program. The memory 62 includes: various media such as ROM, RAM, magnetic disk, USB flash drive, memory card or optical disc that can store program code.

[0093] The processor 61 is connected to the memory 62 and is configured to execute the computer program stored in the memory, so that the battery SOC calibration terminal executes the above-mentioned battery SOC calibration method.

[0094] Preferably, the processor may be a general-purpose processor, including a central processing unit (CPU for short), a network processor (NP for short), etc.; it may also be a digital signal processor (DSP for short), an application specific integrated circuit (ASIC for short), a field programmable gate array (FPGA for short), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0095] The above embodiments merely illustrate the principles and effects of the present invention, rather than limiting the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A method for calibrating the state of charge (SOC) of a battery, characterized in that: The method includes the following steps: Obtain the voltage and cumulative charge capacity during battery charging at a preset time interval; Construct a correlation curve between the cumulative charge capacity and the voltage; Obtain the inflection point of the correlation curve when the battery is approaching full charge, and construct a fitting curve between the cumulative charge capacity and the voltage from the inflection point to the end point of charging based on the correlation curve; Extend the fitting curve to obtain an extension line, and determine the point on the extension line where the voltage is the maximum voltage value of the battery; According to calculate the calibrated SOC corresponding to the charging time n, where represents the reverse cumulative charging capacity between the charging end point and the charging time n, Q cap represents the rated capacity of the battery, represents the calibrated SOC corresponding to the charging end point; It further includes calculating a calibrated SOC corresponding to the charging end point according to where represents the cumulative charging capacity corresponding to the point on the extension line where the voltage is the maximum voltage value of the battery, represents the cumulative charging capacity corresponding to the charging end point on the fitting curve, represents the SOC corresponding to the point on the extension line where the voltage is the maximum voltage value of the battery.

2. The battery SOC calibration method according to claim 1, characterized in that: The cumulative charge capacity during battery charging is obtained by any of the following methods: Obtain the current during battery charging, and obtain the cumulative charge capacity based on the ampere-hour integration method; Obtain the current during battery charging, and obtain the cumulative charge capacity based on the Kalman filtering method; Measure the cumulative charge capacity using an instrument.

3. The battery SOC calibration method according to claim 1, characterized in that: The fitting curve is Q j = m1 × U j + m0, where both m1 and m0 represent the coefficients of the linear equation, and where U j represents the voltage at time j, and Q j represents the cumulative charge capacity charged up to time j.

4. The battery SOC calibration method according to claim 1, wherein: Set to 1.

5. The battery SOC calibration method according to claim 1, wherein: It further includes comparing the calibrated SOC and the measured SOC, and analyzing the error of the measured SOC.

6. The battery SOC calibration method according to claim 1, characterized in that: It further includes, when the battery starts to discharge, using the calibrated SOC corresponding to the end point of charging as the initial SOC for discharging.

7. A battery SOC calibration system, characterized in that: It includes an acquisition module, a construction module, a fitting module, an extension module, and a calibration module; The acquisition module is used to obtain the voltage and cumulative charge capacity during battery charging at a preset time interval; The construction module is used to construct a correlation curve between the cumulative charge capacity and the voltage; The fitting module is used to obtain the inflection point of the correlation curve when the battery is approaching full charge, and construct a fitting curve between the cumulative charge capacity and the voltage from the inflection point to the end point of charging based on the correlation curve; The extension module is used to extend the fitting curve to obtain an extension line, and determine the point on the extension line where the voltage is the maximum voltage value of the battery; The calibration module is used to calculate the calibrated SOC corresponding to the charging time n according to where represents the reverse cumulative charging capacity from the end point of charging to the charging time n, and Q cap represents the rated capacity of the battery Indicates the calibrated SOC corresponding to the end point of charging; According to calculate the calibrated SOC corresponding to the end point of charging, where represents the cumulative charge capacity corresponding to the point on the extension line where the voltage is the maximum voltage value of the battery, represents the cumulative charge capacity corresponding to the end point of charging on the fitting curve, represents the SOC corresponding to the point on the extension line where the voltage is the maximum voltage value of the battery.

8. A storage medium having a computer program stored thereon, characterized in that, When the program is executed by a processor, it implements the battery SOC calibration method according to any one of claims 1 to 6.

9. A battery SOC calibration terminal, characterized in that, It includes: A processor and a memory; The memory is used to store a computer program; The processor is used to execute the computer program stored in the memory, so that the battery SOC calibration terminal executes the battery SOC calibration method according to any one of claims 1 to 6.

Images