Battery charge state correction method, electronic equipment and computer storage medium

Abstract

The invention discloses a state of charge correction method of a battery, electronic equipment and a computer storage medium. The method for correcting the state of charge of the battery comprises the following steps: acquiring a first battery capacity when the battery is fully charged and cut off and a second battery capacity when the battery is fully discharged and cut off; judging whether the battery capacity of the battery meets a preset battery capacity condition or not based on the first battery capacity and the second battery capacity; if the preset battery capacity condition is met, correcting the battery capacity of the battery based on the first battery capacity and the second battery capacity to obtain a corrected battery capacity; and correcting the state of charge of the battery based on the corrected battery capacity. Through the above mode, according to the charge state correction method, the battery capacity is corrected based on the first battery capacity when the battery is fully charged and cut off and the second battery capacity when the battery is fully discharged and cut off, so that the charge state of the battery can be corrected without standing the battery, and the precision of the charge state of the battery is improved.

Description

Technical Field

[0001] This application relates to the technical calculation field of battery management systems, and particularly relates to a method for correcting the state of charge of a battery, an electronic device, and a computer storage medium. Background Art

[0002] In recent years, lithium batteries have been widely used in the energy storage field and the electric vehicle field. The state of charge (SOC, also called remaining charge) of a lithium-ion battery cannot be directly measured by an instrument, and currently, a series of algorithms (such as the ampere-hour integration method, the Kalman filter method, and the neural network method, etc.) are used for estimation. The Kalman filter method and the neural network method have high accuracy, but the algorithms are complex. Especially, the neural network method requires a large amount of data for training in advance. Therefore, they are not widely used in engineering practice. Currently, the most widely used method in the industry is the ampere-hour integration method.

[0003] However, the ampere-hour integration method is also affected by the battery capacity when calculating the state of charge. In the ampere-hour integration method, the battery capacity is regarded as a fixed constant. But in actual engineering practice, the battery capacity will change. As the number of battery cycles increases, the battery capacity will continuously decrease. Therefore, there is an urgent need for a method to correct the battery capacity to correct the state of charge of the battery. Summary of the Invention

[0004] This application proposes a method for correcting the state of charge of a battery, an electronic device, and a computer storage medium, aiming to solve the above problems.

[0005] To solve the above technical problems, a technical solution adopted by this application is: to provide a method for correcting the state of charge of a battery. The method for correcting the state of charge of the battery includes: obtaining a first battery capacity when the battery is fully charged until cut-off and a second battery capacity when the battery is fully discharged until cut-off; judging whether the battery capacity of the battery meets a preset battery capacity condition based on the first battery capacity and the second battery capacity; if the preset battery capacity condition is met, correcting the battery capacity of the battery based on the first battery capacity and the second battery capacity to obtain a corrected battery capacity; correcting the state of charge of the battery based on the corrected battery capacity.

[0006] Among them, the step of judging whether the battery capacity of the battery meets the preset battery capacity condition based on the first battery capacity and the second battery capacity includes: calculating the average value of the first battery capacity and the second battery capacity; judging whether the difference between the average value and a preset battery capacity threshold is less than a preset difference.

[0007] Among them, the state of charge correction method further includes: obtaining a first moment when the battery is fully charged and a second moment when the battery is fully discharged; after the step of determining whether the battery capacity of the battery meets the preset battery capacity condition based on the first battery capacity and the second battery capacity, the state of charge correction method further includes: in response to the battery capacity of the battery meeting the preset battery capacity condition, calculating the time difference before the first moment and the second moment; determining whether the time difference meets the preset time requirement; if the preset time requirement is met, then performing the step of correcting the battery capacity of the battery based on the first battery capacity and the second battery capacity.

[0008] Among them, the step of obtaining a first moment when the battery is fully charged and a second moment when the battery is fully discharged includes: determining whether the battery has reached full charge cut-off or full discharge cut-off; in response to the battery reaching full charge cut-off, recording the first moment when the battery reaches full charge cut-off, waiting for the battery to reach full discharge cut-off, and recording the second moment when the battery reaches full discharge cut-off; in response to the battery reaching full discharge cut-off, recording the second moment when the battery reaches full discharge cut-off, waiting for the battery to reach full charge cut-off, and recording the first moment when the battery reaches full charge cut-off.

[0009] Among them, the step of obtaining a first battery capacity when the battery is fully charged and a second battery capacity when the battery is fully discharged includes: determining whether the battery has reached full charge cut-off or full discharge cut-off; in response to the battery reaching full charge cut-off, recording the first battery capacity of the battery at full charge cut-off, waiting for the battery to reach full discharge cut-off, and recording the second battery capacity of the battery at full discharge cut-off; in response to the battery reaching full discharge cut-off, recording the second battery capacity of the battery at full discharge cut-off, waiting for the battery to reach full charge cut-off, and recording the first battery capacity of the battery at full charge cut-off.

[0010] Among them, the step of correcting the battery capacity based on the first battery capacity and the second battery capacity to obtain a corrected battery capacity includes: calculating the average value of the first battery capacity and the second battery capacity; obtaining the battery capacity before correction and the correction ratio of the battery; calculating the corrected battery capacity based on the battery capacity before correction, the correction ratio, and the average value.

[0011] Among them, the step of correcting the state of charge of the battery based on the corrected battery capacity includes: obtaining the initial battery capacity of the battery; correcting the state of charge using the ampere-hour integration method based on the corrected battery capacity and the initial battery capacity.

[0012] Among them, the open-circuit voltage range of the battery includes a first voltage range, a second voltage range, and a third voltage range, and the second voltage range is located between the first voltage range and the third voltage range. The state-of-charge correction method further includes: obtaining the current open-circuit voltage of the battery; determining whether the current open-circuit voltage is in the first voltage range or the third voltage range; if it is in the first voltage range, correcting the state of charge of the battery based on the first mapping relationship and the open-circuit voltage; if it is in the third voltage range, correcting the state of charge of the battery based on the second mapping relationship and the open-circuit voltage; the first mapping relationship is the mapping relationship between the open-circuit voltage within the preset first voltage range and the state of charge of the battery; the second mapping relationship is the mapping relationship between the open-circuit voltage within the preset third voltage range and the state of charge of the battery.

[0013] To solve the above technical problems, another technical solution adopted by this application is: to provide an electronic device, which includes a processor and a memory connected to the processor. Among them, program data is stored in the memory, and the processor executes the program data stored in the memory to execute the state-of-charge correction method of the battery in any one of the above.

[0014] To solve the above technical problems, another technical solution adopted by this application is: to provide a computer-readable storage medium, which stores program instructions internally, and the program instructions are executed by the processor to implement the state-of-charge correction method of the battery in any one of the above.

[0015] The beneficial effect of this application is: different from the prior art, the state-of-charge correction method of the battery in this application first obtains the first battery capacity when the battery is fully charged and cut off and the second battery capacity when the battery is fully discharged and cut off; and judges whether the battery capacity of the battery meets the preset battery capacity condition based on the first battery capacity and the second battery capacity; if it meets the preset battery capacity condition, the battery capacity of the battery is corrected based on the first battery capacity and the second battery capacity to obtain the corrected battery capacity; finally, the state of charge of the battery is corrected based on the corrected battery capacity. In the above manner, this application can correct the battery capacity based on the first battery capacity when the battery is fully charged and cut off and the second battery capacity when the battery is fully discharged and cut off, and thus can correct the state of charge of the battery without standing the battery, thereby improving the accuracy of the state of charge of the battery. Description of the Drawings

[0016] The drawings here are incorporated into the specification and form a part of this specification. These drawings show embodiments consistent with this application and are used together with the specification to explain the technical solutions of this application.

[0017] Figure 1 It is a schematic flowchart of the first embodiment of the state-of-charge correction method of this application;

[0018] Figure 2 is Figure 1 The flowchart of a specific embodiment of step S102;

[0019] Figure 3 is Figure 1 The flowchart of a specific embodiment of step S103;

[0020] Figure 4 is Figure 1 The flowchart of a specific embodiment of step S104;

[0021] Figure 5 is Figure 1 The flowchart of a specific embodiment of step S101;

[0022] Figure 6 The flowchart of the second embodiment of the state of charge correction method of the present application;

[0023] Figure 7 is Figure 6 The flowchart of a specific embodiment of step S603;

[0024] Figure 8 The flowchart of the third embodiment of the state of charge correction method of the present application;

[0025] Figure 9 The schematic diagram of the OCV-SOC curve of an embodiment of the battery of the present application;

[0026] Figure 10 The schematic diagram of the structure of an embodiment of the electronic device of the present application;

[0027] Figure 11 The schematic diagram of the structure of an embodiment of the computer storage medium of the present application. Detailed implementation manners

[0028] The embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to illustrate the technical solutions of the present application more clearly, so they are only examples and cannot be used to limit the protection scope of the present application.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion.

[0030] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0031] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0032] In recent years, lithium batteries have been widely used in the fields of energy storage and electric vehicles. The state of charge (SOC, also known as the remaining power) of lithium-ion batteries cannot be directly measured by instruments. Currently, a series of algorithms (such as the ampere-hour integration method, the Kalman filter method, and the neural network method, etc.) are used for estimation. The Kalman filter method and the neural network method have high accuracy, but the algorithms are complex, especially the neural network method, which requires a large amount of data for training in advance. Therefore, it is not widely used in engineering practice. At present, the most widely used method in the industry is the ampere-hour integration method.

[0033] The method of obtaining the battery SOC using the ampere-hour integration method is shown in formula (1):

[0034]

[0035] Among them, SOC represents the current battery capacity of the battery, SOC 0 Represents the initial capacity of the battery, C N represents the capacity of the battery, η represents the charge and discharge efficiency, and I represents the battery current.

[0036] From formula (1), we can see that the ampere-hour integration method is simple to calculate and convenient for engineering application. However, it is also affected by the initial state of charge SOC of the battery. 0 The impact on accuracy is huge. Once SOC 0 If there is an error, then the error will be directly reflected in the SOC estimation result. At the same time, formula (1) integrates the current, which introduces the measurement error of the current I into the SOC estimation result. More seriously, this error will continue to accumulate with the estimation iteration, making the SOC estimation result worse and worse. This is the problem of SOC cumulative error.

[0037] In addition, the ampere-hour integration method is also affected by the battery capacity when calculating the state of charge. In formula (1), the battery capacity CN are regarded as a fixed constant. However, in actual engineering practice, the battery capacity C N will change. As the number of battery charge-discharge cycles increases, the battery capacity C N will continuously decrease. Therefore, there is an urgent need for a method to correct the battery capacity to correct the SOC of the battery.

[0038] To solve the above problems, this application first proposes a method for correcting the state of charge of a battery. Please refer to Figure 1 , Figure 1 which is a schematic flowchart of the first embodiment of the state of charge correction method of this application. As Figure 1 shown, the state of charge correction method of this embodiment specifically includes steps S101 to S104:

[0039] Step S101: Obtain the first battery capacity when the battery is fully charged and the second battery capacity when the battery is fully discharged.

[0040] In this embodiment, before correcting the state of charge of the battery, it is first necessary to obtain the first battery capacity when the battery reaches the full charge cut-off point and the second battery capacity when the battery reaches the full discharge cut-off point.

[0041] Exemplarily, taking a lithium iron phosphate battery as an example, the full discharge cut-off point can be selected when the single cell voltage drops to 2.0V (sometimes a higher voltage, such as a value between 2.1V and 2.5V, is also selected to protect the battery). If the battery is charged by a constant current and constant voltage method, the full charge cut-off point can be selected after the battery reaches the constant voltage charging stage (for example, when the single cell is 3.65V, the battery pack with 10 single cells is 36.5V, and so on), and the current drops to 0.02C (if the battery is 24Ah, 1C is 24A, and 0.02C is 0.48A).

[0042] Step S102: Determine whether the battery capacity of the battery meets the preset battery capacity condition based on the first battery capacity and the second battery capacity.

[0043] After obtaining the first battery capacity when the battery reaches the full charge cut-off point and the second battery capacity when the battery reaches the full discharge cut-off point, the average value of the first battery capacity and the second battery capacity can be calculated, the gap between the average value and the preset battery capacity condition can be obtained, and it can be determined whether the gap is within the allowable range. If it is within the allowable range, it is determined that the preset battery capacity condition is satisfied. If it is not within the allowable range, it is determined that the preset battery capacity condition is not satisfied, and the first battery capacity when the battery reaches the full charge cut-off point and the second battery capacity when the battery reaches the full discharge cut-off point are obtained again; wherein, the allowable range of the gap between the average value and the preset battery capacity condition can be set to 5% - 15%. In other embodiments, the allowable range of the gap between the average value and the preset battery capacity condition can also be set according to user requirements, which is not limited herein.

[0044] If the preset battery capacity condition is satisfied, go to step S103.

[0045] Step S103: Correct the battery capacity of the battery based on the first battery capacity and the second battery capacity to obtain the corrected battery capacity.

[0046] If the battery capacity of the battery meets the preset battery capacity condition, the battery capacity can be corrected based on the average value of the first battery capacity and the second battery capacity and the battery correction ratio to obtain the corrected battery capacity of the battery. The calculation method of the corrected battery capacity is as described below and will not be elaborated herein.

[0047] Step S104: Correct the state of charge of the battery based on the corrected battery capacity.

[0048] After obtaining the corrected battery capacity of the battery, the corrected battery capacity can be substituted into formula (1) of the ampere-hour integration method to obtain the state of charge of the battery corresponding to the corrected battery capacity, thereby realizing the correction of the state of charge of the battery.

[0049] Different from the prior art, the method for correcting the state of charge of the battery in this application first obtains the first battery capacity when the battery is fully charged and cut off and the second battery capacity when the battery is fully discharged; and determines whether the battery capacity of the battery meets the preset battery capacity condition based on the first battery capacity and the second battery capacity; if the preset battery capacity condition is satisfied, the battery capacity of the battery is corrected based on the first battery capacity and the second battery capacity to obtain the corrected battery capacity; and finally, the state of charge of the battery is corrected based on the corrected battery capacity. Through the above method, this application can correct the battery capacity based on the first battery capacity when the battery is fully charged and cut off and the second battery capacity when the battery is fully discharged, and then can correct the state of charge of the battery without standing the battery, thereby improving the accuracy of the state of charge of the battery.

[0050] Optionally, the method for determining whether the battery capacity of a battery meets a preset battery capacity condition based on a first battery capacity and a second battery capacity is as follows Figure 2 shown. Please refer to Figure 2 , Figure 2 which Figure 1 is a schematic flowchart of a specific embodiment of step S102. As Figure 2 shown, this embodiment can implement step S102 through the method shown in Figure 2 . The specific implementation steps include steps S201 to S202:

[0051] Step S201: Calculate the average value of the first battery capacity and the second battery capacity.

[0052] After obtaining the first battery capacity when the battery reaches the full charge cut-off point and the second battery capacity when the battery reaches the full discharge cut-off point, the average value of the first battery capacity and the second battery capacity can be calculated.

[0053] Step S202: Determine whether the difference between the average value and a preset battery capacity threshold is less than a preset difference.

[0054] After calculating the average value of the first battery capacity and the second battery capacity, at this time, the preset battery capacity threshold in the preset battery capacity condition can be obtained, and the average value is compared with the preset battery capacity threshold to determine whether the difference between the two is less than the preset difference.

[0055] Among them, if the difference between the two is less than the preset difference, the battery capacity meets the preset battery capacity condition; if the difference between the two is greater than or equal to the preset difference, the battery capacity meets the preset battery capacity condition.

[0056] Optionally, the method for correcting the battery capacity based on the first battery capacity and the second battery capacity to obtain a corrected battery capacity is as follows Figure 3 shown. Please refer to Figure 3 , Figure 3 which Figure 1 is a schematic flowchart of a specific embodiment of step S103. As Figure 3 shown, this embodiment can implement step S103 through the method shown in Figure 3 . The specific implementation steps include steps S301 to S303:

[0057] Step S301: Calculate the average value of the first battery capacity and the second battery capacity.

[0058] When correcting the capacity of the battery, obtain the average value of the first battery capacity and the second battery capacity.

[0059] Step S302: Obtain the battery capacity before correction and the correction ratio of the battery.

[0060] At this time, when correcting the battery, it is also necessary to obtain the battery capacity before correction and the correction ratio of the battery. Among them, the correction ratio is generally set to 30% - 60%.

[0061] Step S303: Calculate the corrected battery capacity based on the battery capacity before correction, the correction ratio, and the average value.

[0062] Finally, calculate the corrected battery capacity based on the battery capacity before correction, the correction ratio, and the average value. Among them, the calculation formula of the corrected battery capacity is shown in formula (2):

[0063]

[0064] Among them, C R is the corrected battery capacity, C N is the battery capacity before correction of the battery, C avg is the average value of the first battery capacity and the second battery capacity, is the correction ratio.

[0065] Optionally, the method for correcting the state of charge of the battery based on the corrected battery capacity is as Figure 4 shown. Please refer to Figure 4 , Figure 4 is Figure 1 a schematic flow chart of a specific embodiment of step S104. As Figure 4 shown, this embodiment can implement step S104 through the method as Figure 4 shown. The specific implementation steps include step S401 to step S402:

[0066] Step S401: Obtain the initial battery capacity of the battery.

[0067] As described above, after obtaining the corrected battery capacity of the battery, when correcting the SOC of the battery, it is also necessary to obtain the initial battery capacity of the battery.

[0068] Step S402: Correct the state of charge using the ampere-hour integration method based on the corrected battery capacity and the initial battery capacity.

[0069] After obtaining the initial battery capacity and the corrected battery capacity of the battery, the two can be substituted into formula (1) of the ampere-hour integration method to recalculate the SOC of the battery, thereby realizing the correction of the SOC of the battery.

[0070] Optionally, the method for obtaining the first battery capacity at the end of full charge and the second battery capacity at the end of full discharge of the battery is as Figure 5 shown. Please refer to Figure 5 , Figure 5 is Figure 1 a schematic flow chart of a specific embodiment of step S101. AsFigure 5 As shown, this embodiment can implement step S101 through the method shown in Figure 5 Specific implementation steps include steps S501 to S503:

[0071] Step S501: Determine whether the battery has reached full charge cut-off or full discharge cut-off.

[0072] When obtaining the first battery capacity at full charge cut-off and the second battery capacity at full discharge cut-off of the battery, it is first necessary to judge the state of the battery to determine whether the battery has reached full charge cut-off or full discharge cut-off.

[0073] Step S502: In response to the battery reaching full charge cut-off, record the first battery capacity of the battery at full charge cut-off, wait for the battery to reach full discharge cut-off, and record the second battery capacity of the battery at full discharge cut-off.

[0074] If the battery reaches full charge cut-off, record the first battery capacity at the current full charge cut-off, and judge whether the discharge of the current battery is effective. If it is effective, wait for the battery to reach full discharge cut-off, and record the second battery capacity of the battery at full discharge cut-off.

[0075] Step S503: In response to the battery reaching full discharge cut-off, record the second battery capacity of the battery at full discharge cut-off, wait for the battery to reach full charge cut-off, and record the first battery capacity of the battery at full charge cut-off.

[0076] If the battery reaches full discharge cut-off, record the second battery capacity at the current full discharge cut-off, and judge whether the charging of the current battery is effective. If it is effective, wait for the battery to reach full charge cut-off, and record the first battery capacity of the battery at full charge cut-off.

[0077] Optionally, the present application further proposes a method for correcting the state of charge of a battery. Please refer to Figure 6 , Figure 6 is a schematic flow chart of the second embodiment of the method for correcting the state of charge of the present application. As shown in Figure 6 The method for correcting the state of charge of this embodiment specifically includes steps S601 to S605:

[0078] Step S601: Obtain the first battery capacity at full charge cut-off and the second battery capacity at full discharge cut-off of the battery.

[0079] Step S601 is the same as step S101 and will not be elaborated here.

[0080] Step S602: Based on the first battery capacity and the second battery capacity, judge whether the battery capacity of the battery meets the preset battery capacity condition.

[0081] Step S602 is the same as step S102 and will not be elaborated here.

[0082] If the preset battery capacity condition is met, go to step S603.

[0083] Step S603: Obtain the first moment when the battery is fully charged and the second moment when the battery is fully discharged, and calculate the time difference between the first moment and the second moment.

[0084] Step S604: Determine whether the time difference meets the preset time requirement.

[0085] After the battery meets the preset battery capacity condition, it is also necessary to obtain the first moment when the battery is fully charged and the second moment when the battery is fully discharged, and calculate the time difference between the first moment and the second moment. At this time, after obtaining the time difference between the full charge cut-off and the full discharge cut-off of the battery, it is determined whether the time difference is within the set range. If it is within the set range, it is determined that the preset time requirement is met. Among them, the set range of time can be set to 24h to 72h in this embodiment. In other embodiments, the set range of time can also be set based on the actual requirements of the battery and will not be limited here.

[0086] If the preset time requirement is met, go to step S605.

[0087] Step S605: Correct the battery capacity of the battery based on the first battery capacity and the second battery capacity to obtain the corrected battery capacity.

[0088] Step S605 is the same as step S103 and will not be elaborated here.

[0089] Step S606: Correct the state of charge of the battery based on the corrected battery capacity.

[0090] Step S606 is the same as step S104 and will not be elaborated here.

[0091] Optionally, the method for obtaining the first moment when the battery is fully charged and the second moment when the battery is fully discharged is as Figure 7 shown. Please refer to Figure 7 , Figure 7 which Figure 6 is the flowchart of a specific embodiment of step S603. As Figure 7 shown, this embodiment can implement the steps of obtaining the first moment when the battery is fully charged and the second moment when the battery is fully discharged in step S603 through the method as Figure 7 shown. The specific implementation steps include steps S701 to S703:

[0092] Step S701: Determine whether the battery has reached full charge cut-off or full discharge cut-off.

[0093] When obtaining the first battery capacity at the full charge cut-off and the second battery capacity at the full discharge cut-off of the battery, it is first necessary to determine the state of the battery to judge whether the battery has reached the full charge cut-off or the full discharge cut-off.

[0094] Step S702: In response to the battery reaching the full charge cut-off, record the first moment when the battery reaches the full charge cut-off, wait for the battery to reach the full discharge cut-off, and record the second moment when the battery reaches the full discharge cut-off.

[0095] If the battery reaches the full charge cut-off, record the first moment when the full charge cut-off currently occurs, and judge whether the discharge of the current battery is effective. If it is effective, wait for the battery to reach the full discharge cut-off, and record the second moment of the battery when the full discharge cut-off occurs.

[0096] Step S703: In response to the battery reaching the full discharge cut-off, record the second moment when the battery reaches the full discharge cut-off, wait for the battery to reach the full charge cut-off, and record the first moment when the battery reaches the full charge cut-off.

[0097] If the battery reaches the full discharge cut-off, record the second battery capacity when the full discharge cut-off currently occurs, and judge whether the charging of the current battery is effective. If it is effective, wait for the battery to reach the full charge cut-off, and record the first battery capacity of the battery when the full charge cut-off occurs.

[0098] Among them, in this embodiment, the steps of obtaining the first battery capacity at the full charge cut-off and the second battery capacity at the full discharge cut-off of the battery and the steps of obtaining the first moment at the full charge cut-off and the second moment at the full discharge cut-off of the battery can be carried out synchronously.

[0099] That is, the first battery capacity and the first moment at the full charge cut-off of the battery can be obtained synchronously, and the second battery capacity and the second moment at the full discharge cut-off can be obtained.

[0100] Optionally, based on the above embodiment, the present application further proposes a method for correcting the state of charge of a battery. Please refer to Figure 8 , Figure 8 is a schematic flow chart of the third embodiment of the method for correcting the state of charge of the present application. In this embodiment, the open circuit voltage range of the battery includes a first voltage range, a second voltage range, and a third voltage range, and the second voltage range is located between the first voltage range and the third voltage range. As Figure 8 shown, the method for correcting the state of charge of this embodiment further includes steps S801 to S804:

[0101] Step S801: Obtain the current open circuit voltage of the battery.

[0102] In this embodiment, first obtain the current open circuit voltage of the battery after a long-term static state.

[0103] Step S802: Determine whether the current open-circuit voltage is within the first voltage range or the third voltage range.

[0104] After obtaining the current open-circuit voltage of the battery, it is necessary to determine whether the current open-circuit voltage is within the first voltage range or the third voltage range; if the current open-circuit voltage is within the first voltage range, go to step S803, and if the current open-circuit voltage is within the third voltage range, go to step S804.

[0105] Step S803: Correct the state of charge of the battery based on the first mapping relationship and the open-circuit voltage.

[0106] If the open-circuit voltage of the battery is within the first voltage range, correct the state of charge of the battery based on the first mapping relationship between the open-circuit voltage within the preset first voltage range and the state of charge of the battery and the open-circuit voltage.

[0107] Step S804: If it is within the third voltage range, correct the state of charge of the battery based on the second mapping relationship and the open-circuit voltage.

[0108] Wherein, in this embodiment, the first mapping relationship is the mapping relationship between the open-circuit voltage within the preset first voltage range and the state of charge of the battery; the second mapping relationship is the mapping relationship between the open-circuit voltage within the preset third voltage range and the state of charge of the battery.

[0109] If the open-circuit voltage of the battery is within the third voltage range, correct the state of charge of the battery based on the second mapping relationship between the open-circuit voltage within the preset third voltage range and the state of charge of the battery and the open-circuit voltage.

[0110] As described above, research shows that there is a certain functional relationship between the open-circuit voltage and the SOC of a lithium battery, as shown in formula (3):

[0111] OCV = f(SOC) (3)

[0112] Wherein, OCV represents the open-circuit voltage of the lithium battery, that is, the voltage value measured at both ends of the lithium battery after a long-term static state (more than 30 minutes), and SOC represents the state of charge of the battery.

[0113] Please refer to Figure 9 , Figure 9 which is a schematic diagram of the OCV-SOC curve of an embodiment of the battery in this application. In engineering practice, the SOC value is often corrected through the Figure 9 shown OCV-SOC curve, so as to solve the cumulative error problem of the above SOC estimation. This method is called the open-circuit voltage correction method. As Figure 9As shown, the OCV-SOC curve of the ternary battery is approximately a straight line. Therefore, after establishing the functional relationship between OCV and SOC through the OCV-SOC curve, the SOC can be corrected by the OCV value measured after the lithium battery stands still.

[0114] However, for the lithium iron phosphate battery as shown in Figure 9 , its OCV-SOC curve has a plateau region (i.e., the part that is approximately a horizontal line in Figure 9 ). If the OCV value after standing still falls within the plateau region, because there is a certain error in the measurement of OCV (generally several mV to more than ten mV), it will cause the accuracy of the SOC corrected by this curve to decrease instead. This may cause overcharging and over-discharging of the battery in engineering practice, and further lead to fire or even explosion.

[0115] In this embodiment, taking the lithium iron phosphate battery as an example, as can be seen from Figure 9 , the two ends of the OCV-SOC curve of the lithium iron phosphate battery are as shown in Figure 9 . Avoid the plateau region of the lithium iron phosphate battery and only correct at the two ends of the OCV-SOC curve of the lithium iron phosphate battery.

[0116] Therefore, in this embodiment, only the formulas at the two ends of the OCV-SOC curve need to be established, that is, to construct the first mapping relationship between the open-circuit voltage within the preset first voltage range and the state of charge of the battery and the second mapping relationship between the open-circuit voltage within the preset third voltage range and the state of charge of the battery as described above, as shown in formula (4):

[0117]

[0118] Among them, OCV L represents the current open-circuit voltage of the battery when the power is low, SOC L represents the remaining capacity of the battery when the power is low, OCV H represents the current open-circuit voltage of the battery when the power is high, and SOC H represents the remaining capacity of the battery when the power is high. In this embodiment, the first voltage range can be set to 3.1V to 2.0V, and the third voltage range can be set to 3.4V to 3.65V. In other embodiments, the first voltage range and the third voltage range can be set based on actual needs and are not limited herein.

[0119] Optionally, the present application further proposes an electronic device. Please refer to Figure 10 , Figure 10 is a schematic structural diagram of an embodiment of the electronic device of the present application. The electronic device 200 includes a processor 201 and a memory 202 connected to the processor 201.

[0120] The processor 201 may also be referred to as a CPU (Central Processing Unit). The processor 201 may be an integrated circuit chip with the ability to process signals. The processor 201 may also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0121] The memory 202 is used to store the program data required for the operation of the processor 201.

[0122] The processor 201 is also used to execute the program data stored in the memory 202 to implement the state-of-charge correction method for the battery in any of the above items.

[0123] Optionally, the present application further proposes a computer storage medium. Please refer to Figure 11 , Figure 11 which is a schematic structural diagram of an embodiment of the computer storage medium of the present application.

[0124] The computer storage medium 300 of the embodiment of the present application stores program instructions 310 internally, and the program instructions 310 are executed to implement the state-of-charge correction method for the battery in any of the above items.

[0125] Among them, the program instructions 310 may form a program file and be stored in the above storage medium in the form of a software product, so that an electronic device (which may be a personal computer, a server, or a network device, etc.) or a processor can execute all or part of the steps of the methods in various embodiments of the present application. And the foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs that can store program codes, or terminal devices such as computers, servers, mobile phones, and tablets.

[0126] The computer storage medium 300 of this embodiment may be, but is not limited to, a USB flash drive, an SD card, a PD optical drive, a mobile hard disk, a large-capacity floppy drive, a flash memory, a multimedia memory card, a server, etc.

[0127] In one embodiment, a computer program product or a computer program is provided. The computer program product or the computer program includes computer instructions, and the computer instructions are stored in a computer storage medium. The processor of the electronic device reads the computer instructions from the computer storage medium, and the processor executes the computer instructions, so that the electronic device executes the steps in the above method embodiments.

[0128] In addition, when the above functions are implemented in the form of software functions and sold or used as independent products, they can be stored in a storage medium readable by a mobile terminal. That is, the present application also provides a storage device storing program data, and the program data can be executed to implement the methods of the above embodiments. The storage device can be a USB flash drive, an optical disc, a server, etc. That is to say, the present application can be embodied in the form of a software product, which includes several instructions for causing an intelligent terminal to execute all or part of the steps of the methods of the various embodiments.

[0129] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0130] Any process or method description in the flowchart or described in other ways herein can be understood as representing a mechanism, segment, or portion of code including one or more executable instructions for implementing a specific logical function or process. The scope of the preferred embodiments of the present application includes additional implementations, where the functions can be executed in a substantially simultaneous manner or in a reverse order according to the involved functions, rather than in the order shown or discussed, which should be understood by those skilled in the technical field to which the embodiments of the present application belong.

[0131] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definitional sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (which can be a personal computer, server, network device, or other system that can fetch instructions from the instruction execution system, apparatus, or device and execute the instructions), or used in conjunction with these instruction execution systems, apparatuses, or devices. For the purposes of this specification, a "computer storage medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which a program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then storing it in a computer memory.

[0132] The above are only embodiments of the present application, and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present application.

Claims

1. A method for correcting the state of charge of a battery, characterized in that, it includes: obtaining a first battery capacity when the battery is fully charged and a second battery capacity when the battery is fully discharged; judging whether the battery capacity of the battery meets a preset battery capacity condition based on the first battery capacity and the second battery capacity; if the preset battery capacity condition is met, correcting the battery capacity of the battery based on the first battery capacity and the second battery capacity to obtain a corrected battery capacity; correcting the state of charge of the battery based on the corrected battery capacity.

2. The state of charge correction method according to claim 1, characterized in that, the step of judging whether the battery capacity of the battery meets a preset battery capacity condition based on the first battery capacity and the second battery capacity includes: calculating an average value of the first battery capacity and the second battery capacity; judging whether the difference between the average value and a preset battery capacity threshold is less than a preset difference.

3. The state of charge correction method according to claim 2, characterized in that, the state of charge correction method further includes: obtaining a first moment when the battery is fully charged and a second moment when the battery is fully discharged; after the step of judging whether the battery capacity of the battery meets a preset battery capacity condition based on the first battery capacity and the second battery capacity, the state of charge correction method further includes: in response to the battery capacity of the battery meeting the preset battery capacity condition, calculating a time difference before the first moment and the second moment; judging whether the time difference meets a preset time requirement; if the preset time requirement is met, performing the step of correcting the battery capacity of the battery based on the first battery capacity and the second battery capacity.

4. The state of charge correction method according to claim 3, characterized in that, the step of obtaining a first moment when the battery is fully charged and a second moment when the battery is fully discharged includes: judging whether the battery has reached the full charge cut-off or the full discharge cut-off; in response to the battery reaching the full charge cut-off, recording the first moment when the battery reaches the full charge cut-off, waiting for the battery to reach the full discharge cut-off, and recording the second moment when the battery reaches the full discharge cut-off; in response to the battery reaching the full discharge cut-off, recording the second moment when the battery reaches the full discharge cut-off, waiting for the battery to reach the full charge cut-off, and recording the first moment when the battery reaches the full charge cut-off.

5. The state of charge correction method according to claim 1, characterized in that, the step of obtaining a first battery capacity when the battery is fully charged and a second battery capacity when the battery is fully discharged includes: judging whether the battery has reached the full charge cut-off or the full discharge cut-off; in response to the battery reaching the full charge cut-off, recording the first battery capacity of the battery at the full charge cut-off, waiting for the battery to reach the full discharge cut-off, and recording the second battery capacity of the battery at the full discharge cut-off; In response to the full discharge cut-off of the battery, record the second battery capacity of the battery at the full discharge cut-off, and wait for the battery to reach the full charge cut-off, and record the first battery capacity of the battery at the full charge cut-off.

6. The state of charge correction method according to claim 1, wherein, the step of correcting the battery capacity based on the first battery capacity and the second battery capacity to obtain a corrected battery capacity includes: calculating the average value of the first battery capacity and the second battery capacity; obtaining the battery capacity and correction ratio of the battery before correction; calculating the corrected battery capacity based on the battery capacity before correction, the correction ratio and the average value.

7. The state of charge correction method according to claim 1, wherein, the step of correcting the state of charge of the battery based on the corrected battery capacity includes: obtaining the initial battery capacity of the battery; correcting the state of charge based on the corrected battery capacity and the initial battery capacity of the battery by using the ampere-hour integration method.

8. The state of charge correction method according to claim 1, wherein, the open-circuit voltage range of the battery includes a first voltage range, a second voltage range and a third voltage range, and the second voltage range is located between the first voltage range and the third voltage range. The state of charge correction method further includes: obtaining the current open-circuit voltage of the battery; judging whether the current open-circuit voltage is in the first voltage range or the third voltage range; if it is in the first voltage range, correcting the state of charge of the battery based on the first mapping relationship and the open-circuit voltage; if it is in the third voltage range, correcting the state of charge of the battery based on the second mapping relationship and the open-circuit voltage; the first mapping relationship is a preset mapping relationship between the open-circuit voltage in the first voltage range and the state of charge of the battery; the second mapping relationship is a preset mapping relationship between the open-circuit voltage in the third voltage range and the state of charge of the battery.

9. An electronic device, wherein, the electronic device includes a processor and a memory connected to the processor. Among them, program data is stored in the memory, and the processor executes the program data stored in the memory to execute the state of charge correction method of the battery according to any one of claims 1-8.

10. A computer storage medium, wherein, program instructions are stored therein, and the program instructions are executed to implement the state of charge correction method of the battery according to any one of claims 1-8.

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