Calibration method and device, computer device, electronic equipment, medium and product

Abstract

The invention discloses an inflection point calibration method, a health degree estimation method, an electric quantity balancing method, an inflection point calibration device, a computer device, electronic equipment, a computer readable storage medium and a computer program product. In the battery inflection point calibration method, the effectiveness of a plurality of to-be-determined inflection points can be obtained and investigated in a predetermined voltage interval. Under the condition that the undetermined inflection point is newly acquired, the candidate inflection point can be compared with the newly acquired undetermined inflection point, and whether the newly acquired undetermined inflection point is effective or not is judged according to the electric quantity difference corresponding to the two inflection points and the change rate of the voltage relative to the electric quantity. And if the newly acquired undetermined inflection point is valid, considering that the credibility of the newly acquired undetermined inflection point is higher, and replacing the newly acquired undetermined inflection point as a candidate inflection point. After each undetermined inflection point is investigated, the candidate inflection point is a calibration inflection point. On the premise of ensuring the triggering rate of the undetermined inflection point in the preset voltage interval, the accuracy of the calibrated inflection point is ensured, and the condition of calibrating a wrong inflection point is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of inflection point calibration, and more specifically, to a battery inflection point calibration method, a battery health estimation method, a battery charge balancing method, a battery inflection point calibration device, a computer device, an electronic device, a computer-readable storage medium, and a computer program product. Background Art

[0002] During the charge and discharge process of the battery, the point where the voltage changes fastest is called the inflection point. The inflection point is an important parameter of the battery. The battery status can be evaluated and the battery performance can be improved based on the inflection point of the battery. Therefore, it is of great significance to accurately calibrate the inflection point. However, the voltage curve of the battery during the charge and discharge process may also fluctuate abnormally due to the voltage fluctuation of the connected power grid or the pulse voltage fluctuation, and it is easy to be miscalibrated as an inflection point. This will affect the accuracy of the battery status assessment and therefore cannot improve the battery performance accordingly. Summary of the invention

[0003] Embodiments of the present application provide a battery inflection point calibration method, a battery health estimation method, a battery charge balancing method, a battery inflection point calibration device, a computer device, an electronic device, a computer-readable storage medium, and a computer program product.

[0004] The inflection point calibration method of a battery provided in an embodiment of the present application includes: when the battery is charged and discharged, sequentially obtaining at least one pending inflection point within a predetermined voltage range; calibrating the first pending inflection point as a candidate inflection point; when the number of pending inflection points is greater than one, sequentially examining the next pending inflection point, and when the next pending inflection point satisfies a first predetermined condition, replacing the next pending inflection point as the candidate inflection point, the first predetermined condition being that the rate of change of the voltage of the next pending inflection point with respect to the charge is greater than a first predetermined multiple of the rate of change of the voltage of the candidate inflection point with respect to the charge, or the predetermined condition being that the rate of change of the voltage of the next pending inflection point with respect to the charge is greater than the rate of change of the voltage of the candidate inflection point with respect to the charge and the charge difference between the next pending inflection point and the candidate inflection point is less than a first predetermined charge difference; calibrating the candidate inflection point as the calibration inflection point.

[0005] In the inflection point calibration method of the battery provided in the embodiment of the present application, the validity of multiple pending inflection points can be obtained and examined within a predetermined voltage interval. In the case of a newly obtained pending inflection point, the candidate inflection point can be compared with the newly obtained pending inflection point, and the validity of the newly obtained pending inflection point can be determined based on the power difference corresponding to the two inflection points and the rate of change of voltage relative to power. If the newly obtained pending inflection point is valid, it is considered that the newly obtained pending inflection point has a higher credibility, and the newly obtained pending inflection point is replaced as the candidate inflection point. After examining each pending inflection point, the candidate inflection point is the calibration inflection point.

[0006] In this way, the calibration method provided in the embodiment of the present application obtains the pending inflection points through multiple investigations, and determines whether the pending inflection points are valid by setting a judgment mechanism. On the premise of ensuring the trigger rate of the pending inflection points within the predetermined voltage range, the accuracy of the calibrated inflection points is also ensured to avoid the situation of calibrating the wrong inflection points.

[0007] In certain embodiments, when the battery is charged and discharged, at least one pending inflection point is sequentially obtained within a predetermined voltage range, including: when the battery is charged and discharged, obtaining the voltage and current of the battery; determining the battery charge and the rate of change of the battery voltage relative to the battery charge according to the voltage and current of the battery; when the battery voltage is within a predetermined voltage range, determining the pending inflection point according to the rate of change of the battery voltage relative to the battery charge.

[0008] In some embodiments, the battery has N voltage platform intervals, N is an integer greater than or equal to 2, and when the voltage is within a predetermined voltage interval, the pending inflection point is determined according to the rate of change of the battery voltage relative to the charge, including: when the battery voltage is between two of the voltage platform intervals, the pending inflection point is determined according to the rate of change of the battery voltage relative to the charge.

[0009] In certain embodiments, the calibration method includes: when the number of the pending inflection points is greater than one, examining the next pending inflection point in turn, and when the next pending inflection point satisfies a second predetermined condition, calibrating the candidate inflection point and the pending inflection point as invalid inflection points.

[0010] In some embodiments, the second predetermined condition is that the rate of change of the voltage relative to the charge of the next pending inflection point is less than a second predetermined multiple of the rate of change of the voltage relative to the charge of the candidate inflection point and the charge difference corresponding to the next pending inflection point and the candidate inflection point is greater than or equal to a second predetermined charge difference.

[0011] The battery health estimation method provided in the embodiment of the present application includes: when the battery is charged and discharged, at least one pending inflection point is obtained in sequence within a predetermined voltage range; the first pending inflection point is calibrated as a candidate inflection point; when the number of the pending inflection points is greater than one, the next pending inflection point is examined in sequence, and when the next pending inflection point satisfies a first predetermined condition, the next pending inflection point is replaced as the candidate inflection point; the first predetermined condition is that the rate of change of the voltage of the next pending inflection point relative to the charge is greater than a first predetermined multiple of the rate of change of the voltage of the candidate inflection point relative to the charge, or the predetermined condition is that the rate of change of the voltage of the next pending inflection point relative to the charge is greater than the rate of change of the voltage of the candidate inflection point relative to the charge and the charge difference between the next pending inflection point and the candidate inflection point is less than a first predetermined charge difference; the candidate inflection point is calibrated as a calibrated inflection point; and the health of the battery is determined according to the calibrated inflection point.

[0012] The power balancing method provided in the embodiment of the present application includes: when the battery is charged and discharged, at least one pending inflection point is sequentially obtained within a predetermined voltage range; the first pending inflection point is calibrated as a candidate inflection point; when the number of the pending inflection points is greater than one, the next pending inflection point is examined in turn, and when the next pending inflection point satisfies a first predetermined condition, the next pending inflection point is replaced as the candidate inflection point; the first predetermined condition is that the rate of change of the voltage of the next pending inflection point relative to the power is greater than a first predetermined multiple of the rate of change of the voltage of the candidate inflection point relative to the power, or the predetermined condition is that the rate of change of the voltage of the next pending inflection point relative to the power is greater than the rate of change of the voltage of the candidate inflection point relative to the power and the power difference between the next pending inflection point and the candidate inflection point is less than a first predetermined power difference; calibrating the candidate inflection point as a calibrated inflection point; when the battery needs to be balanced, the charging and discharging of the battery is controlled according to the calibrated inflection point of the battery to balance the power of the battery.

[0013] The inflection point calibration device of the battery provided in the embodiment of the present application includes an acquisition module and a calibration module. The acquisition module is configured to sequentially acquire at least one pending inflection point within a predetermined voltage range when the battery is charged and discharged. The calibration module is configured to calibrate the first pending inflection point as a candidate inflection point. The calibration module is also configured to examine the next pending inflection point in sequence when the number of pending inflection points is greater than one, and replace the next pending inflection point as a candidate inflection point when the next pending inflection point satisfies a predetermined first predetermined condition, the first predetermined condition being that the rate of change of the voltage of the next pending inflection point relative to the electric quantity is greater than the first predetermined multiple of the rate of change of the voltage of the candidate inflection point relative to the electric quantity, or the predetermined condition being that the rate of change of the voltage of the next pending inflection point relative to the electric quantity is greater than the rate of change of the voltage of the candidate inflection point relative to the electric quantity and the electric quantity difference corresponding to the next pending inflection point and the candidate inflection point is less than the first predetermined electric quantity difference. The calibration module is also configured to calibrate the candidate inflection point as a calibration inflection point.

[0014] The computer device provided in the embodiment of the present application includes a memory and a processor. The memory is configured to store a computer program. When the processor executes the computer program, it implements the inflection point calibration method, health estimation method and power balancing method provided in the embodiment of the present application.

[0015] The electronic device provided in the embodiments of the present application includes the inflection point calibration device provided in the embodiments of the present application or the computer device provided in the embodiments of the present application.

[0016] The computer-readable storage medium provided in the embodiments of the present application stores a computer program / instruction. When the computer program is executed by one or more processors, the inflection point calibration method, health estimation method and power balancing method provided in the embodiments of the present application are implemented.

[0017] The computer program product provided in the embodiments of the present application includes a computer program / instruction. When the computer program / instruction is executed by a processor, the inflection point calibration method, health estimation method and power balancing method provided in the embodiments of the present application are implemented.

[0018] In the inflection point calibration method of the battery provided in the embodiment of the present application, the validity of multiple pending inflection points can be obtained and examined within a predetermined voltage interval. In the case of a newly obtained pending inflection point, the candidate inflection point can be compared with the newly obtained pending inflection point, and the validity of the newly obtained pending inflection point can be determined based on the power difference corresponding to the two inflection points and the rate of change of voltage relative to power. If the newly obtained pending inflection point is valid, it is considered that the newly obtained pending inflection point has a higher credibility, and the newly obtained pending inflection point is replaced as the candidate inflection point. After examining each pending inflection point, the candidate inflection point is the calibration inflection point.

[0019] In this way, the calibration method provided in the embodiment of the present application obtains the pending inflection points through multiple investigations, and determines whether the pending inflection points are valid by setting a judgment mechanism. On the premise of ensuring the trigger rate of the pending inflection points within the predetermined voltage range, the accuracy of the calibrated inflection points is also ensured to avoid the situation of calibrating the wrong inflection points.

[0020] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0022] Figure 1 is a schematic diagram of an inflection point calibration method provided in certain embodiments of the present application;

[0023] Figure 2 is a schematic diagram of a health estimation method and a power balancing method provided in certain embodiments of the present application;

[0024] Figure 3 is a schematic diagram of an inflection point calibration method provided in certain embodiments of the present application;

[0025] Figure 4 is a curve graph corresponding to the battery inflection point provided in certain embodiments of the present application;

[0026] Figure 5 is a schematic diagram of an inflection point calibration method provided in certain embodiments of the present application;

[0027] Figure 6 is a curve graph corresponding to the battery inflection point provided in certain embodiments of the present application;

[0028] Figure 7 is a curve graph corresponding to the battery inflection point provided in certain embodiments of the present application;

[0029] Figure 8 It is a curve graph corresponding to the battery inflection point provided in certain embodiments of the present application. DETAILED DESCRIPTION

[0030] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions from beginning to end. The embodiments described below with reference to the accompanying drawings are optional and are only used to explain the embodiments of the present application, and cannot be understood as limiting the embodiments of the present application.

[0031] During the charge and discharge process of the battery, the point where the voltage changes fastest is called the inflection point. The inflection point is an important parameter of the battery. The battery status can be evaluated and the battery performance can be improved based on the inflection point of the battery. Therefore, it is of great significance to accurately calibrate the inflection point. However, the voltage curve of the battery during the charge and discharge process may also fluctuate abnormally due to the voltage fluctuation of the connected power grid or the pulse voltage fluctuation, and it is easy to be miscalibrated as an inflection point. This will affect the accuracy of the battery status assessment and therefore cannot improve the battery performance accordingly.

[0032] In order to solve the above technical problems, the embodiments of the present application provide a battery inflection point calibration method, a battery health estimation method, a battery charge balancing method, a battery inflection point calibration device, a computer device, an electronic device, a computer-readable storage medium and a computer program product.

[0033] Reference Figure 1 The inflection point calibration method of the battery provided in the embodiment of the present application includes:

[0034] Step 01: When the battery is being charged or discharged, at least one undetermined inflection point is sequentially obtained within a predetermined voltage range;

[0035] Step 021: Mark the first undetermined inflection point as a candidate inflection point;

[0036] Step 022: when the number of pending inflection points is greater than one, examine the next pending inflection point in turn, and when the next pending inflection point satisfies a first predetermined condition, replace the next pending inflection point as a candidate inflection point, the first predetermined condition being that the rate of change of the voltage of the next pending inflection point relative to the electric quantity is greater than a first predetermined multiple of the rate of change of the voltage of the candidate inflection point relative to the electric quantity, or the predetermined condition being that the rate of change of the voltage of the next pending inflection point relative to the electric quantity is greater than the rate of change of the voltage of the candidate inflection point relative to the electric quantity and the electric quantity difference corresponding to the next pending inflection point and the candidate inflection point is less than a first predetermined electric quantity difference;

[0037] Step 03: Calibrate the candidate inflection points as calibration inflection points.

[0038] In the inflection point calibration method of the battery provided in the embodiment of the present application, the validity of multiple pending inflection points can be obtained and examined within a predetermined voltage interval. In the case of a newly obtained pending inflection point, the candidate inflection point can be compared with the newly obtained pending inflection point, and the validity of the newly obtained pending inflection point can be determined based on the power difference corresponding to the two inflection points and the rate of change of voltage relative to power. If the newly obtained pending inflection point is valid, it is considered that the newly obtained pending inflection point has a higher credibility, and the newly obtained pending inflection point is replaced as the candidate inflection point. After examining each pending inflection point, the candidate inflection point is the calibration inflection point.

[0039] In this way, the calibration method provided in the embodiment of the present application obtains the pending inflection points through multiple investigations, and determines whether the pending inflection points are valid by setting a judgment mechanism. On the premise of ensuring the trigger rate of the pending inflection points within the predetermined voltage range, the accuracy of the calibrated inflection points is also ensured to avoid the situation of calibrating the wrong inflection points.

[0040] Specifically, in step 01, the predetermined voltage interval may be a pre-set voltage interval. When the material and parameters of the battery are known, the preset voltage curve of the battery during the charging and discharging process can be determined, and the voltage interval corresponding to the preset inflection point in the voltage curve is determined. The predetermined voltage interval may cover the vicinity of the preset inflection point, ensuring that even if the voltage fluctuates abnormally, the inflection point after deviation will not be outside the predetermined voltage interval.

[0041] During the process of battery charging and discharging, the battery voltage changes. The inflection point of the battery voltage within the predetermined voltage range can be obtained and recorded as a pending inflection point, so that the calibration inflection point can be determined from the pending inflection point later to ensure that the calibration inflection point is within the predetermined voltage range and avoid calibration inflection point errors. The pending inflection point can be marked as A1~An, where n is any positive integer.

[0042] In step 021, A1 can be marked as a candidate inflection point.

[0043] In step 022, if n is equal to 1, the output candidate inflection point is A1. If n is greater than 1, the next undetermined inflection point is examined in sequence from A2 to An to determine the output candidate inflection point. Each examination is to compare the candidate inflection point with the next undetermined inflection point. If the next undetermined inflection point meets the first predetermined condition, the original candidate inflection point can be discarded and the next undetermined inflection point can be replaced by a new candidate inflection point.

[0044] For example, taking the case where a total of three pending inflection points are obtained within a predetermined voltage range, the three pending inflection points are marked as A1 to A3, the rate of change of the voltage corresponding to A1 relative to the electric quantity is X1, the electric quantity corresponding to A1 is Q1, the rate of change of the voltage corresponding to A2 relative to the electric quantity is X2, the electric quantity corresponding to A2 is Q2, the rate of change of the voltage corresponding to A3 relative to the electric quantity is X3, the electric quantity corresponding to A3 is Q3, the first predetermined multiple is k1, and the first predetermined electric quantity difference is △Q1.

[0045] In some embodiments, A1 can be first marked as a candidate inflection point, and A2 can be compared with A1. If X2 is greater than k1*X1, or X2 is greater than X1 and Q2-Q1 is less than ΔQ1, A2 can replace A1 as a candidate inflection point. If the above conditions are not met, A1 can be a candidate inflection point.

[0046] If A2 is compared with A1 and A1 is a candidate inflection point, A3 is compared with A1. If X3 is greater than k1*X1, or X3 is greater than X1 and Q3-Q1 is less than △Q1, A3 can replace A1 as a candidate inflection point. If the above conditions are not met, A1 can be a candidate inflection point.

[0047] If A2 is a candidate inflection point after comparison with A1, A3 is compared with A2. If X3 is greater than k1*X2, or X3 is greater than X2 and Q3-Q2 is less than △Q1, A3 can replace A2 as a candidate inflection point. If the above conditions are not met, A2 can be a candidate inflection point.

[0048] In some embodiments, k1 is 1.5, and ΔQ1 is 3% of the rated capacity of the battery.

[0049] In step 03, the candidate inflection points outputted by calibration are calibrated inflection points.

[0050] The battery health prediction method provided in the embodiment of the present application includes the above-mentioned steps 01, 021, 022, and 03. After the above-mentioned step 03, the battery health prediction method also includes: determining the battery health according to the calibration inflection point.

[0051] Specifically, refer to Figure 2 The constant term inflection point capacity (QHVTP) and the charge capacity after the high inflection point (QHVP) can be used to calibrate the power corresponding to the inflection point in two predetermined voltage intervals. If the battery is fully charged, the maximum capacity (Qmax) can be calculated by adding the constant term inflection point capacity (QHVTP) to the charge capacity after the high inflection point (QHVP), Qmax = QHVTP + QHVP. The current battery health status can be obtained by calculating the ratio of Qmax to the maximum capacity at the factory.

[0052] The battery power balancing method provided in the embodiment of the present application includes the above-mentioned steps 01, 021, 022, and 03. After the above-mentioned step 03, the battery power balancing method also includes: when the battery needs to be balanced, controlling the charging and discharging of the battery according to the calibrated inflection point of the battery to balance the battery.

[0053] Specifically, refer to Figure 2 There is a difference ΔQHVTP between the electric charges QHVTP_i corresponding to the high inflection points of different batteries. Through the self-discharge of the battery with relatively high charge, the charge of the battery with relatively high charge is reduced by ΔQHVTP to achieve the purpose of improving battery consistency and realizing battery charge balance.

[0054] The inflection point calibration device of the battery provided in the embodiment of the present application includes an acquisition module and a calibration module. The acquisition module is configured to sequentially acquire at least one pending inflection point within a predetermined voltage range when the battery is charged and discharged. The calibration module is configured to calibrate the first pending inflection point as a candidate inflection point. The calibration module is also configured to examine the next pending inflection point in sequence when the number of pending inflection points is greater than one, and replace the next pending inflection point as a candidate inflection point when the next pending inflection point satisfies a predetermined first predetermined condition, the first predetermined condition being that the rate of change of the voltage of the next pending inflection point relative to the electric quantity is greater than the first predetermined multiple of the rate of change of the voltage of the candidate inflection point relative to the electric quantity, or the predetermined condition being that the rate of change of the voltage of the next pending inflection point relative to the electric quantity is greater than the rate of change of the voltage of the candidate inflection point relative to the electric quantity and the electric quantity difference corresponding to the next pending inflection point and the candidate inflection point is less than the first predetermined electric quantity difference. The calibration module is also configured to calibrate the candidate inflection point as a calibration inflection point.

[0055] The computer device provided in the embodiment of the present application includes a memory and a processor. The memory is configured to store a computer program. When the processor executes the computer program, it implements the inflection point calibration method, health estimation method and power balancing method provided in the embodiment of the present application.

[0056] The electronic device provided in the embodiments of the present application includes the inflection point calibration device provided in the embodiments of the present application or the computer device provided in the embodiments of the present application.

[0057] The computer-readable storage medium provided in the embodiments of the present application stores a computer program / instruction. When the computer program is executed by one or more processors, the inflection point calibration method, health estimation method and power balancing method provided in the embodiments of the present application are implemented.

[0058] The computer program product provided in the embodiments of the present application includes a computer program / instruction. When the computer program / instruction is executed by a processor, the inflection point calibration method, health estimation method and power balancing method provided in the embodiments of the present application are implemented.

[0059] Reference Figure 3 In some embodiments, step 01: when the battery is charged or discharged, sequentially obtaining at least one pending inflection point within a predetermined voltage interval includes:

[0060] Step 011: When the battery is charging or discharging, obtain the voltage and current of the battery;

[0061] Step 012: determining the battery power and the rate of change of the battery voltage relative to the battery power according to the battery voltage and current;

[0062] Step 013: When the battery voltage is within a predetermined voltage range, determine a pending inflection point according to a rate of change of the battery voltage relative to the battery charge.

[0063] Specifically, in step 011, during the process of battery charging and discharging, the voltage and current of the battery are detected and recorded in real time.

[0064] In step 012, the corresponding relationship between the battery voltage and the battery charge is determined based on the recorded voltage and current of the battery and the battery charge value that changes during the charge and discharge process, and the rate of change of the battery voltage relative to the battery charge curve is determined based on the voltage-charge curve.

[0065] In step 013, when the battery voltage is within a predetermined voltage range, the undetermined inflection point is determined according to the rate of change of the battery voltage relative to the power. When the battery voltage is within the predetermined voltage range, the point on the rate of change of power-power curve reaches a peak value, and the point can be determined as the undetermined inflection point.

[0066] In some embodiments, the voltage-capacity curve and the rate of change of capacity-capacity curve can refer to Figure 4 .

[0067] In some embodiments, the battery has N voltage platform intervals, N is an integer greater than or equal to 2, and when the voltage is within a predetermined voltage interval, the pending inflection point is determined based on the rate of change of the battery voltage relative to the charge, including: when the battery voltage is between two voltage platform intervals, the pending inflection point is determined based on the rate of change of the battery voltage relative to the charge.

[0068] Specifically, the N voltage platform intervals of the battery can be set as voltage platform interval X1 to voltage platform interval XN, the voltage interval between voltage platform interval X1 and voltage platform interval X2 can be the predetermined voltage interval 1, and the voltage interval between voltage platform interval XN-1 and voltage platform interval XN can be the predetermined voltage interval N-1.

[0069] Among them, when the battery voltage is located in a predetermined voltage interval between two voltage platform intervals, the above steps 01 to 03 can be executed to obtain the calibration inflection point corresponding to the predetermined voltage interval, so that N-1 calibration inflection points corresponding to N-1 predetermined voltage intervals can be obtained.

[0070] by Figure 4 For example, the battery has three voltage platform intervals, and the voltage interval between every two voltage platform intervals is a predetermined voltage interval. There are two calibrated inflection points in total, and the power corresponding to the two calibrated inflection points is recorded as QLVTP and QHVTP respectively.

[0071] In certain embodiments, the calibration method comprises:

[0072] When the number of pending inflection points is greater than one, the next pending inflection point is examined in sequence, and when the next pending inflection point satisfies a second predetermined condition, the candidate inflection point and the pending inflection point are marked as invalid inflection points.

[0073] In the battery inflection point calibration method provided in the embodiment of the present application, the validity of multiple pending inflection points can be obtained and examined within a predetermined voltage range. In the case of a newly obtained pending inflection point, the candidate inflection point can be compared with the newly obtained pending inflection point. If the pending inflection point satisfies the second predetermined condition, it is considered that the risk of obtaining an incorrect inflection point is high, and the inflection point obtained in this charge and discharge is invalid, and the battery health estimation and power balancing will not be performed based on the obtained inflection point.

[0074] In some embodiments, the second predetermined condition is that the rate of change of the voltage relative to the charge of the next pending inflection point is less than a second predetermined multiple of the rate of change of the voltage relative to the charge of the candidate inflection point and the charge difference corresponding to the next pending inflection point and the candidate inflection point is greater than or equal to the second predetermined charge difference.

[0075] Specifically, taking the example of obtaining a total of three pending inflection points within a predetermined voltage range, the three pending inflection points are marked as A1~A3, the rate of change of the voltage corresponding to A1 relative to the electric quantity is X1, the electric quantity corresponding to A1 is Q1, the rate of change of the voltage corresponding to A2 relative to the electric quantity is X2, the electric quantity corresponding to A2 is Q2, the rate of change of the voltage corresponding to A3 relative to the electric quantity is X3, the electric quantity corresponding to A3 is Q3, the second predetermined multiple is k2, and the second predetermined electric quantity difference is △Q2.

[0076] In some embodiments, A1 may be first calibrated as a candidate inflection point, and A2 is compared with A1. If X2 is less than k2*X1 and Q2-Q1 is greater than or equal to ΔQ1, the inflection point is wrong and no new inflection point is obtained.

[0077] If A2 is compared with A1 and A1 is the candidate inflection point, A3 is compared with A1. If X3 is less than k2*X1 and Q3-Q1 is greater than or equal to △Q2, the inflection point is wrong and no new inflection point is obtained.

[0078] If A2 is a candidate inflection point after comparison with A1, A3 is compared with A2. If X3 is less than k2*X2 and Q3-Q2 is greater than or equal to △Q2, the inflection point is wrong and no new inflection point is obtained.

[0079] In some embodiments, k2 is 1.5, and ΔQ2 is 3% of the rated capacity of the battery.

[0080] Reference Figure 5In the above step 022, when the number of pending inflection points is greater than 1, the newly acquired pending inflection point and the candidate inflection point are queried. If the newly acquired pending inflection point meets the above first predetermined condition, the newly acquired pending inflection point replaces the candidate inflection point. If the newly acquired pending inflection point meets the above second predetermined condition, the inflection point acquired during this charge and discharge process is invalid. If the newly acquired pending inflection point does not meet the above first predetermined condition and the above second predetermined condition, the candidate inflection point is maintained unchanged. After the battery charge and discharge are completed, the candidate inflection point is calibrated as the calibration inflection point.

[0081] Reference Figure 6 , within the predetermined voltage range, two pending inflection points are obtained, and the first pending inflection point is first determined as the candidate inflection point. Since the voltage-to-electricity change rate corresponding to the second pending inflection point is greater than 1.5 times the voltage-to-electricity change rate corresponding to the first pending inflection point, the second pending inflection point replaces the candidate inflection point. After the charge and discharge are completed, the second pending inflection point is the calibration inflection point.

[0082] Reference Figure 7 , curve L1 may be a charge-discharge curve of voltage B1, and curve L2 may be a charge-discharge curve of voltage B2. Battery B1 has a predetermined voltage interval, which may be a range of 3350mv to 3450mv. Battery B2 has two predetermined voltage intervals, the first predetermined voltage interval may be a range of 3250mv to 3350mv, and the second predetermined voltage interval may be a range of 3400mv to 3450mv.

[0083] For battery B1, a pending inflection point is obtained within the range of 3350 mv to 3450 mv, and the pending inflection point is the correct inflection point.

[0084] For battery B2, a pending inflection point is obtained within the range of 3250mv to 3350mv, which is the correct inflection point. Two pending inflection points are obtained within the range of 3400mv to 3450mv, and the difference between the power corresponding to the second pending inflection point and the power corresponding to the first pending inflection point is greater than 3% of the battery calibrated power, and the voltage-power change rate corresponding to the second pending inflection point is less than 1.5 times the voltage-power change rate corresponding to the first pending inflection point, so the second pending inflection point is an incorrect inflection point.

[0085] Reference Figure 8 After the wrong inflection point is determined, all the inflection points obtained this time are invalid, and the inflection points corresponding to the curves L1 and L2 are cleared.

[0086] In the description of this specification, the descriptions with reference to the terms "certain embodiments", "in an example", "exemplarily", etc., mean that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0087] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0088] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are optional and cannot be understood as limitations to the present application. A person skilled in the art can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for calibrating the inflection point of a battery, characterized in that: The inflection point calibration method comprises: When the battery is charged and discharged, sequentially obtaining at least one inflection point to be determined within a predetermined voltage interval; Marking the first undetermined inflection point as a candidate inflection point; In the case where the number of the pending inflection points is greater than one, the next pending inflection point is examined in sequence, and in the case where the next pending inflection point satisfies a first predetermined condition, the next pending inflection point is replaced as the candidate inflection point, the first predetermined condition being that the rate of change of the voltage of the next pending inflection point relative to the electric quantity is greater than a first predetermined multiple of the rate of change of the voltage of the candidate inflection point relative to the electric quantity, or the predetermined condition being that the rate of change of the voltage of the next pending inflection point relative to the electric quantity is greater than the rate of change of the voltage of the candidate inflection point relative to the electric quantity and the electric quantity difference corresponding to the next pending inflection point and the candidate inflection point is less than a first predetermined electric quantity difference; The candidate inflection point is calibrated as a calibrated inflection point.

2. The battery inflection point calibration method according to claim 1, characterized in that: The method of sequentially acquiring at least one pending inflection point within a predetermined voltage interval when the battery is being charged or discharged comprises: When the battery is charged or discharged, obtaining the voltage and current of the battery; Determining the battery power and the rate of change of the battery voltage relative to the battery power according to the battery voltage and current; When the voltage of the battery is within a predetermined voltage range, the undetermined inflection point is determined according to a rate of change of the voltage of the battery relative to the power level.

3. The battery inflection point calibration method according to claim 2, characterized in that: The battery has N voltage platform intervals, where N is an integer greater than or equal to 2, and when the voltage is within a predetermined voltage interval, determining the undetermined inflection point according to a rate of change of the voltage of the battery relative to the amount of electricity includes: When the voltage of the battery is between the two voltage platform intervals, the undetermined inflection point is determined according to the rate of change of the voltage of the battery relative to the charge.

4. The battery inflection point calibration method according to claim 1, characterized in that: The calibration method comprises: When the number of the pending inflection points is greater than one, the next pending inflection point is examined in turn, and when the next pending inflection point satisfies a second predetermined condition, the candidate inflection point and the pending inflection point are marked as invalid inflection points.

5. The battery inflection point calibration method according to claim 4, characterized in that: The second predetermined condition is that the rate of change of the voltage relative to the charge of the next pending inflection point is less than a second predetermined multiple of the rate of change of the voltage relative to the charge of the candidate inflection point and the charge difference corresponding to the next pending inflection point and the candidate inflection point is greater than or equal to a second predetermined charge difference.

6. A method for estimating battery health, characterized in that: The health status estimation method comprises: When the battery is charged and discharged, sequentially obtaining at least one inflection point to be determined within a predetermined voltage interval; Marking the first undetermined inflection point as a candidate inflection point; When the number of the pending inflection points is greater than one, examine the next pending inflection point in turn, and when the next pending inflection point satisfies the first predetermined condition, replace the next pending inflection point as the candidate inflection point; The first predetermined condition is that the rate of change of the voltage relative to the power of the next inflection point to be determined is greater than a first predetermined multiple of the rate of change of the voltage relative to the power of the candidate inflection point, or the predetermined condition is that the rate of change of the voltage relative to the power of the next inflection point to be determined is greater than the rate of change of the voltage relative to the power of the candidate inflection point and the power difference between the next inflection point to be determined and the candidate inflection point is less than a first predetermined power difference; Calibrate the candidate inflection point as a calibration inflection point; The health of the battery is determined according to the calibrated inflection point.

7. A battery power balancing method, characterized in that: The power balancing method comprises: When the battery is charged and discharged, sequentially obtaining at least one inflection point to be determined within a predetermined voltage interval; Marking the first undetermined inflection point as a candidate inflection point; When the number of the pending inflection points is greater than one, examine the next pending inflection point in turn, and when the next pending inflection point satisfies the first predetermined condition, replace the next pending inflection point as the candidate inflection point; The first predetermined condition is that the rate of change of the voltage relative to the power of the next inflection point to be determined is greater than a first predetermined multiple of the rate of change of the voltage relative to the power of the candidate inflection point, or the predetermined condition is that the rate of change of the voltage relative to the power of the next inflection point to be determined is greater than the rate of change of the voltage relative to the power of the candidate inflection point and the power difference between the next inflection point to be determined and the candidate inflection point is less than a first predetermined power difference; Calibrate the candidate inflection point as a calibration inflection point; When the battery needs to be balanced, the charging and discharging of the battery is controlled according to the calibrated inflection point of the battery to balance the power of the battery.

8. A battery inflection point calibration device, characterized in that: The calibration device comprises: an acquisition module, configured to sequentially acquire at least one undetermined inflection point within a predetermined voltage interval when the battery is charged or discharged; A calibration module is configured to calibrate the first pending inflection point as a candidate inflection point. The calibration module is also configured to examine the next pending inflection point in turn when the number of the pending inflection points is greater than one, and replace the next pending inflection point as the candidate inflection point when the next pending inflection point satisfies a first predetermined condition. The first predetermined condition is that the rate of change of the voltage of the next pending inflection point with respect to the electrical quantity is greater than a first predetermined multiple of the rate of change of the voltage of the candidate inflection point with respect to the electrical quantity, or the predetermined condition is that the rate of change of the voltage of the next pending inflection point with respect to the electrical quantity is greater than the rate of change of the voltage of the candidate inflection point with respect to the electrical quantity and the electrical quantity difference corresponding to the next pending inflection point and the candidate inflection point is less than a first predetermined electrical quantity difference. The calibration module is also configured to calibrate the candidate inflection point as a calibration inflection point.

9. A computer device, characterized in that: The computer device includes a memory and a processor, the memory is configured to store a computer program, and when the processor executes the computer program, it implements the battery inflection point calibration method described in any one of claims 1 to 5, the battery health estimation method described in claim 6, or the battery pack charge balancing method described in claim 7.

10. An electronic device, characterized in that: The electronic device comprises: Battery; The battery inflection point calibration device as described in claim 8 or the computer device as described in claim 9.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program. When the computer program is executed by one or more processors, it implements the battery inflection point calibration method described in any one of claims 1 to 5, the battery health estimation method described in claim 6, or the battery pack charge balancing method described in claim 7.

12. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instruction is executed by the processor, the inflection point calibration method of the battery described in any one of claims 1 to 5, the health estimation method of the battery described in claim 6, or the battery pack power balancing method described in claim 7 is implemented.

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