Consistency detection method and system in battery circulation process

Abstract

The embodiment of the invention provides a consistency detection method and system in a battery circulation process, and the method comprises the steps: detecting the weight and internal resistance of a target battery, and selecting a to-be-detected battery based on a detection result; setting a test environment, performing a charge-discharge cycle test on the to-be-tested battery, and recording the discharge capacity, the charge capacity and the actual SOC of the battery in the middle and later cycles of the charge-discharge cycle test; based on the discharge capacity, the charge capacity and the actual SOC of the battery, respectively calculating corresponding parameter standard deviations, including a discharge capacity standard deviation, a charge capacity standard deviation and an actual SOC standard deviation of the battery; and determining a parameter error range based on the parameter standard deviation, screening the to-be-detected batteries through the parameter error range, and determining optimal batteries in consistency grouping.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium batteries, and in particular to a consistency detection method and system during a battery cycle. Background Art

[0002] With the rapid development of new energy, lithium-ion batteries are widely used in various industries due to their environmental protection, good cycle performance and high energy density. For example, they are used in 3C products, electric vehicles and various facility energy storage devices. During use, the inconsistency of lithium batteries is a key point that needs to be considered, especially in battery packs (such as battery packs in electric vehicles). This inconsistency will significantly affect the performance and life of the entire system.

[0003] The inconsistency of lithium batteries mainly comes from the manufacturing and use process. Static inconsistency is affected by production processes, technologies, equipment, etc., and is difficult to eliminate. Dynamic inconsistency is affected by operating conditions, environment, etc., and has a greater impact on performance. Therefore, in actual use, it is also indispensable to identify the consistency of the battery during operation.

[0004] At present, the consistency screening method is usually carried out after the capacity is offline. The batteries are grouped in a shelved state and the batteries are sorted using performance indicators such as capacity, internal resistance, and K value. The static consistency screening method is fast, but it is difficult to predict the changing trend of the battery and has low accuracy, which is not conducive to the subsequent performance of the battery. Summary of the invention

[0005] In view of the problems existing in the prior art, an embodiment of the present invention provides a method and system for detecting consistency during a battery cycle.

[0006] An embodiment of the present invention provides a method for detecting consistency during a battery cycle, the method comprising: Detect the weight and internal resistance of the target battery, and select the battery to be tested based on the test results; Setting a test environment, performing a charge-discharge cycle test on the battery to be tested, and recording the discharge capacity, charge capacity, and actual SOC of the battery in the later cycles of the charge-discharge cycle test; Based on the discharge capacity, the charge capacity and the actual SOC of the battery, respectively calculate the corresponding parameter standard deviations, the parameter standard deviations including: the discharge capacity standard deviation, the charge capacity standard deviation and the actual SOC standard deviation of the battery; The parameter error range is determined based on the parameter standard deviation, and the batteries to be tested are screened according to the parameter error range to determine the preferred batteries for the consistency grouping.

[0007] In one embodiment, the method further comprises: Setting the ambient temperature and current, charging the battery under test with a constant current, and switching to constant voltage charging after the battery under test is charged to a preset value until the battery under test is fully charged; The fully charged battery to be tested is discharged with a constant current until the battery voltage reaches the cut-off voltage.

[0008] In one embodiment, the method further comprises: Based on the discharge capacity, the capacity value of the battery to be tested that reaches the rated capacity of the discharge capacity is calculated, and the ratio of the capacity value to the discharge capacity is calculated to obtain the actual SOC of the battery.

[0009] In one embodiment, the method further comprises: Obtaining a target number of the preferred batteries, adjusting an error multiple between the parameter standard deviation and an average value of test data based on the target number, and calculating a parameter error range through the error multiple between the average value and the parameter standard deviation; The batteries to be tested are screened through the parameter error range to determine the preferred batteries whose discharge capacity, charge capacity and actual SOC of the batteries are within the corresponding parameter error range.

[0010] In one embodiment, the method further comprises: The preferred batteries are sorted according to the discharge capacity, the charge capacity and the actual SOC of the battery, and the preferred batteries are divided into groups according to the sorting results.

[0011] An embodiment of the present invention provides a consistency detection system during a battery cycle, the system comprising: A detection module is used to detect the weight and internal resistance of the target battery and select the battery to be tested based on the detection results; A test module, used to set a test environment, perform a charge-discharge cycle test on the battery to be tested, and record the discharge capacity, charge capacity and actual SOC of the battery in the later cycle of the charge-discharge cycle test; A calculation module, used to calculate the corresponding parameter standard deviation based on the discharge capacity, the charge capacity and the actual SOC of the battery, respectively, wherein the parameter standard deviation includes: a discharge capacity standard deviation, a charge capacity standard deviation and a battery actual SOC standard deviation; A screening module is used to determine a parameter error range based on the parameter standard deviation, screen the batteries to be tested through the parameter error range, and determine a preferred battery for consistency grouping.

[0012] In one embodiment, the system further comprises: A charging module, used to set the ambient temperature and current size, charge the battery to be tested with a constant current, and switch to constant voltage charging after the battery to be tested is charged to a preset value until the battery to be tested is fully charged; The discharge module is used to discharge the fully charged battery to be tested at a constant current until the battery voltage reaches the cut-off voltage.

[0013] In one embodiment, the system further comprises: The second calculation module is used to calculate the capacity value of the battery to be tested to reach the rated capacity of the discharge capacity based on the discharge capacity, calculate the ratio of the capacity value to the discharge capacity, and obtain the actual SOC of the battery.

[0014] An embodiment of the present invention provides an electronic device, including a processor and a memory; The processor is connected to the memory; The memory is used to store executable program code; The processor runs a program corresponding to the executable program code by reading the executable program code stored in the memory, so as to execute the method described in one or more embodiments.

[0015] An embodiment of the present invention provides a non-transitory computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the consistency detection method during the battery cycling process are implemented.

[0016] In view of the above, in one or more embodiments of the present specification, the weight and internal resistance of the target battery are detected, and the battery to be tested is selected based on the detection results; the test environment is set, and the battery to be tested is subjected to charge and discharge cycle tests, and the discharge capacity, charging capacity and actual SOC of the battery in the middle and late cycles of the charge and discharge cycle test are recorded; based on the discharge capacity, charging capacity and actual SOC of the battery, the corresponding parameter standard deviations are calculated respectively, and the parameter standard deviations include: discharge capacity standard deviation, charging capacity standard deviation, and actual SOC standard deviation of the battery; the parameter error range is determined based on the parameter standard deviation, and the battery to be tested is screened through the parameter error range to determine the preferred battery for consistency grouping. In this way, the battery can be screened by parameter difference based on the data during the cycle. While the operation is simple, the battery performance can be accurately predicted through the cycle process, thereby improving the accuracy of the detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 This is a flow chart of a method for detecting consistency during a battery cycle provided by an embodiment of this specification.

[0019] Figure 2 It is a structural schematic diagram of a consistency detection system during a battery cycle process provided by an embodiment of this specification.

[0020] Figure 3 It is a structural schematic diagram of an electronic device provided by an embodiment of this specification. DETAILED DESCRIPTION

[0021] The subject matter described herein will now be discussed with reference to example embodiments. It should be understood that the discussion of these embodiments is only to enable those skilled in the art to better understand and implement the subject matter described herein, and is not a limitation of the scope of protection, applicability or examples set forth in the claims. The functions and arrangements of the elements discussed can be changed without departing from the scope of protection of the contents of this specification. Various examples can omit, replace or add various processes or components as needed. For example, the described method can be performed in an order different from the described order, and various steps can be added, omitted or combined. In addition, the features described relative to some examples can also be combined in other examples.

[0022] As used herein, the term "including" and its variations represent open terms, meaning "including but not limited to". The term "based on" means "based at least in part on". The terms "one embodiment" and "an embodiment" mean "at least one embodiment". The term "another embodiment" means "at least one other embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other definitions may be included below, whether explicit or implicit. Unless the context clearly indicates otherwise, the definition of a term is consistent throughout the specification.

[0023] like Figure 1 As shown, an embodiment of the present invention provides a method for detecting consistency during battery cycling, comprising: Step S101, detecting the weight and internal resistance of a target battery, and selecting a battery to be tested based on the detection results.

[0024] Specifically, when it is necessary to perform consistency detection on the target battery, it is necessary to first select a battery to be tested with a consistency basis from the target battery. Among them, the consistency basis detection method can be through detecting the weight and internal resistance of the target battery. The weight usually reflects the consistency of the internal materials of the battery, and the internal resistance is directly related to the energy loss and heat generation of the battery during operation, obtaining the preset weight range and internal resistance standard, and selecting the target battery that meets the weight range and internal resistance standard as the battery to be tested. Among them, the weight range can be that the deviation between the weight of the target battery and the standard weight is less than a preset percentage, and the internal resistance standard is a preset smaller internal resistance range.

[0025] Step S102, setting a test environment, performing a charge-discharge cycle test on the battery to be tested, and recording the discharge capacity, charge capacity and actual SOC of the battery in the later cycles of the charge-discharge cycle test.

[0026] Specifically, the test environment of the battery to be tested is set, wherein the test environment may include the ambient temperature and the current size, such as placing the screened battery in a well-controlled temperature environment (such as a thermostat), and setting the ambient temperature to 25±2°C adapted to the battery. Then, a small to medium-intensity current (e.g., 1 / 10C to 1 / 2C) is used for charge and discharge cycle testing, and the charge and discharge cycle testing may be multiple charge and discharge cycles. The cycle process includes first charging in constant current (CC) mode, and then switching to constant voltage (CV) mode to continue charging until full when the battery voltage reaches a predetermined value. Discharging is performed at a constant current until the battery voltage drops to the cut-off voltage, so that the internal chemical state of the battery tends to be stable through multiple charge and discharge cycles in a stable environment, thereby obtaining more accurate and reliable capacity data. In order to obtain more accurate capacity data, during multiple charge and discharge cycles, after each charge and discharge, the battery is given a certain amount of rest time (e.g., 1 hour) to allow the internal chemical reaction of the battery to reach a state of equilibrium before entering the next cycle, which can further reduce the measurement error caused by internal chemical imbalance.

[0027] In the charge and discharge cycle test, the discharge capacity, charge capacity and actual SOC of the battery in the later cycle are obtained. For example, if three cycles of charge and discharge are performed, the charging process in the third cycle is analyzed, because the chemical substances inside the battery are distributed stably in the later cycles, and the measured data is the most accurate. The measured data include: the actual discharge capacity C0 measured in the third cycle; the data of the constant current charging stage during the third cycle, that is, the amount of electricity charged in CC mode, which represents the absorption capacity of the battery under constant current charging conditions, which is the battery's charge capacity C1; and based on the actual discharge capacity C0 measured previously, the capacity value C2 corresponding to when the battery reaches 90% of its rated capacity is calculated. Then use the formula (C2 / C0)*100% to calculate the actual SOC percentage of the battery at this point, which is the actual SOC of the battery.

[0028] Step S103, based on the discharge capacity, the charge capacity and the actual SOC of the battery, respectively calculate the corresponding parameter standard deviations, the parameter standard deviations include: discharge capacity standard deviation, charge capacity standard deviation, and actual SOC standard deviation of the battery.

[0029] Specifically, when calculating the discharge capacity, charge capacity and actual SOC of the battery, the corresponding standard deviations are calculated respectively, including: counting the actual discharge capacity C0 of all the batteries to be tested, and then calculating the standard deviation S1 of C0; counting the charge capacity C1 charged in the constant current charging stage of all the batteries to be tested, and then calculating the standard deviation S2 of C1; counting the actual SOC percentages of all the batteries to be tested at the 90% SOC point (rated capacity), and then calculating the standard deviation S3 of these percentages.

[0030] Step S104, determining a parameter error range based on the parameter standard deviation, screening the batteries to be tested by using the parameter error range, and determining preferred batteries for consistency grouping.

[0031] Specifically, the parameter error range is determined based on the parameter standard deviation, where the standard deviation σ is a statistic of the parameter, indicating the degree of dispersion between a set of values ​​and their average value, and 1σ, 2σ, and 3σ represent one standard deviation, two standard deviations, and three standard deviations of the data distribution, respectively, i.e., the error multiple. In this embodiment, the number of preferred batteries (batteries that pass the consistency test) is obtained, and the error multiple between the parameter standard deviation and the average value of the test data is adjusted according to the target number. For example, when the error multiple is 1, i.e., the parameter error range of one standard deviation range, about 68.27% of the data (battery) load requirements are within the parameter error range of the average value ± one standard deviation; when the error multiple is 2, i.e., the parameter error range of two standard deviations range, about 95.45% of the data (battery) load requirements are within the parameter error range of the average value ± two standard deviations; when the error multiple is 3, i.e., the parameter error range of three standard deviations range, about 99.73% of the data (battery) load requirements are within the parameter error range of the average value ± three standard deviations. The parameter error range is used to screen the batteries to be tested and determine the preferred batteries for consistency grouping.

[0032] For example, the screening process: the average value of the discharge capacity C0 is 2000mAh, and the standard deviation S1 is 50mAh; the average value of the charging capacity C1 in the constant current charging stage is 1800mAh, and the standard deviation S2 is 40mAh; the average value of the actual SOC percentage at 90% SOC is 90.5%, and the standard deviation S3 is 0.5%.

[0033] If the mean ± 2σ range is selected as the parameter error range: C0: 2000±2*50=[1900, 2100]mAh C1: 1800±2*40=[1720, 1880]mAh 90% SOC percentage: 90.5±2*0.5 =[89.5%, 91.5%] The screening criteria are: discharge capacity C0 is between [1900, 2100] mAh, charging capacity C1 in the constant current charging stage is between [1720, 1880] mAh, and the actual SOC percentage at 90% SOC is between [89.5%, 91.5%]. The preferred battery is determined based on the screening criteria.

[0034] In addition, for the preferred batteries, they can also be sorted according to the discharge capacity, charging capacity and actual SOC of the battery, and the preferred batteries can be divided into groups according to the sorting results. For example, a multidimensional sorting algorithm (such as K-means clustering or hierarchical clustering) can be used to simultaneously consider C0, C1 and 90% SOC percentage, so as to determine the battery groups with high consistency in multiple parameters, and group the battery groups with high consistency in multiple parameters to ensure their consistent performance under actual working conditions.

[0035] The embodiment of the present invention provides a method for detecting consistency during a battery cycle, which detects the weight and internal resistance of a target battery, selects a battery to be tested based on the detection results; sets a test environment, performs a charge-discharge cycle test on the battery to be tested, and records the discharge capacity, charge capacity, and actual SOC of the battery in the middle and late cycles of the charge-discharge cycle test; calculates the corresponding parameter standard deviations based on the discharge capacity, charge capacity, and actual SOC of the battery, respectively, and the parameter standard deviations include: discharge capacity standard deviation, charge capacity standard deviation, and actual SOC standard deviation of the battery; determines the parameter error range based on the parameter standard deviation, and screens the battery to be tested through the parameter error range to determine the preferred battery for consistency grouping. In this way, the battery can be screened through the parameter difference of the data during the cycle, which is simple to operate, and can also accurately predict the battery performance through the cycle process, thereby improving the accuracy of the detection.

[0036] See also Figure 2 , Figure 2 Schematic diagram of a consistency detection system for a battery cycle provided in an embodiment of the present application. Figure 2 As shown, the system comprises: The detection module S201 is used to detect the weight and internal resistance of the target battery and select the battery to be tested based on the detection results; The test module S202 is used to set the test environment, perform a charge-discharge cycle test on the battery to be tested, and record the discharge capacity, charge capacity and actual SOC of the battery in the later cycle of the charge-discharge cycle test; A calculation module S203 is used to calculate the corresponding parameter standard deviation based on the discharge capacity, the charge capacity and the actual SOC of the battery, wherein the parameter standard deviation includes: a discharge capacity standard deviation, a charge capacity standard deviation and a battery actual SOC standard deviation; The screening module S204 is used to determine a parameter error range based on the parameter standard deviation, screen the batteries to be tested according to the parameter error range, and determine preferred batteries for consistency grouping.

[0037] In another embodiment, a battery cycle consistency detection system further includes: A charging module, used to set the ambient temperature and current size, charge the battery to be tested with a constant current, and switch to constant voltage charging after the battery to be tested is charged to a preset value until the battery to be tested is fully charged; The discharge module is used to discharge the fully charged battery to be tested at a constant current until the battery voltage reaches a cut-off voltage.

[0038] In another embodiment, a battery cycle consistency detection system further includes: The second calculation module is used to calculate the capacity value of the battery to be tested to reach the rated capacity of the discharge capacity based on the discharge capacity, calculate the ratio of the capacity value to the discharge capacity, and obtain the actual SOC of the battery.

[0039] Those skilled in the art can clearly understand that the technical solutions of the embodiments of the present application can be implemented with the help of software and / or hardware. The "unit" and "module" in this specification refer to software and / or hardware that can independently complete or cooperate with other components to complete specific functions, where the hardware can be, for example, a field programmable gate array (FPGA), an integrated circuit (IC), etc.

[0040] Each processing unit and / or module of the embodiments of the present application may be implemented by an analog circuit that implements the functions described in the embodiments of the present application, or may be implemented by software that executes the functions described in the embodiments of the present application.

[0041] See also Figure 3 , which shows a schematic diagram of the structure of an electronic device involved in an embodiment of the present application, the electronic device can be used to implement Figure 1 The method in the embodiment shown. Figure 3 As shown, the electronic device 300 may include: at least one processor 301 , at least one network interface 304 , a user interface 303 , a memory 305 , and at least one communication bus 302 .

[0042] The communication bus 302 is used to realize the connection and communication between these components.

[0043] The user interface 303 may include a display screen (Display) and a camera (Camera). Optionally, the user interface 303 may also include a standard wired interface and a wireless interface.

[0044] The network interface 304 may optionally include a standard wired interface or a wireless interface (such as a WI-FI interface).

[0045] Among them, the processor 301 may include one or more processing cores. The processor 301 uses various interfaces and lines to connect various parts of the entire electronic device 300, and executes various functions and processes data of the terminal 300 by running or executing instructions, programs, code sets or instruction sets stored in the memory 305, and calling data stored in the memory 305. Optionally, the processor 301 can be implemented in at least one hardware form of digital signal processing (Digital Signal Processing, DSP), field programmable gate array (Field-Programmable Gate Array, FPGA), and programmable logic array (Programmable Logic Array, PLA). The processor 301 can integrate one or a combination of a processor (Central Processing Unit, CPU), an image processor (Graphics Processing Unit, GPU) and a modem. Among them, the CPU mainly processes the operating system, user interface and application programs; the GPU is responsible for rendering and drawing the content to be displayed on the display screen; the modem is used to process wireless communications. It can be understood that the above-mentioned modem may not be integrated into the processor 301, and it can be implemented separately through a chip.

[0046] Among them, the memory 305 may include a random access memory (Random Access Memory, RAM) and may also include a read-only memory (Read-Only Memory). Optionally, the memory 305 includes a non-transitory computer-readable storage medium. The memory 305 can be used to store instructions, programs, codes, code sets or instruction sets. The memory 305 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above-mentioned various method embodiments, etc.; the data storage area may store data involved in the above-mentioned various method embodiments, etc. The memory 305 may also be optionally at least one storage device located away from the aforementioned processor 301. As Figure 3 As shown, the memory 305 as a computer storage medium may include an operating system, a network communication module, a user interface module, and program instructions.

[0047] exist Figure 3 In the electronic device 300 shown, the user interface 303 is mainly used to provide an input interface for the user and obtain the data input by the user; and the processor 301 can be used to call the interactive application based on image generation stored in the memory 305, and perform the following operations: detect the weight and internal resistance of the target battery, and select the battery to be tested based on the detection results; set the test environment, perform charge and discharge cycle tests on the battery to be tested, and record the discharge capacity, charging capacity and actual SOC of the battery in the middle and late cycles of the charge and discharge cycle test; based on the discharge capacity, charging capacity and actual SOC of the battery, respectively calculate the corresponding parameter standard deviation, the parameter standard deviation includes: discharge capacity standard deviation, charging capacity standard deviation, actual SOC standard deviation of the battery; determine the parameter error range based on the parameter standard deviation, screen the battery to be tested through the parameter error range, and determine the preferred battery for consistency grouping.

[0048] The present application also provides a computer-readable storage medium on which a computer program is stored, and when the program is executed by a processor, the steps of the above method are implemented. The computer-readable storage medium may include, but is not limited to, any type of disk, including a floppy disk, an optical disk, a DVD, a CD-ROM, a micro drive, and a magneto-optical disk, a ROM, a RAM, an EPROM, an EEPROM, a DRAM, a VRAM, a flash memory device, a magnetic card or an optical card, a nanosystem (including a molecular memory IC), or any type of medium or device suitable for storing instructions and / or data.

[0049] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0050] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0051] In the several embodiments provided in the present application, it should be understood that the disclosed device can be implemented in other ways. For example, the device embodiments described above are only schematic, such as the division of the units, which is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some service interfaces, and the indirect coupling or communication connection of devices or units can be electrical or other forms.

[0052] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual measurement needs to achieve the purpose of the solution of this embodiment.

[0053] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0054] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a memory, including a number of instructions to enable a computer device (which can be a personal computer, server or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned memory includes: U disk, read-only memory (ROM), random access memory (RAM), mobile hard disk, disk or optical disk and other media that can store program codes.

[0055] A person skilled in the art may understand that all or part of the steps in the various methods of the above embodiments may be completed by entering a program to instruct related hardware, and the program may be stored in a computer-readable memory, which may include a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0056] The above is a description of a specific embodiment of the specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

Claims

1. A method for detecting consistency during battery cycling, the method comprising: Detect the weight and internal resistance of the target battery, and select the battery to be tested based on the test results; Setting a test environment, performing a charge-discharge cycle test on the battery to be tested, and recording the discharge capacity, charge capacity, and actual SOC of the battery in the later cycles of the charge-discharge cycle test; Based on the discharge capacity, the charge capacity and the actual SOC of the battery, respectively calculate the corresponding parameter standard deviations, the parameter standard deviations including: the discharge capacity standard deviation, the charge capacity standard deviation and the actual SOC standard deviation of the battery; The parameter error range is determined based on the parameter standard deviation, and the batteries to be tested are screened according to the parameter error range to determine the preferred batteries for the consistency grouping.

2. The method according to claim 1, characterized in that The setting of the test environment and performing a charge-discharge cycle test on the battery to be tested includes: Setting the ambient temperature and current, charging the battery under test with a constant current, and switching to constant voltage charging after the battery under test is charged to a preset value until the battery under test is fully charged; The fully charged battery to be tested is discharged with a constant current until the battery voltage reaches the cut-off voltage.

3. The method according to claim 1, characterized in that The method further comprises: Based on the discharge capacity, the capacity value of the battery to be tested that reaches the rated capacity of the discharge capacity is calculated, and the ratio of the capacity value to the discharge capacity is calculated to obtain the actual SOC of the battery.

4. The method according to claim 1, characterized in that: The step of determining a parameter error range based on the parameter standard deviation, screening the batteries to be tested by using the parameter error range, and determining a preferred battery for consistency grouping includes: Obtaining a target number of the preferred batteries, adjusting an error multiple between the parameter standard deviation and an average value of test data based on the target number, and calculating a parameter error range through the error multiple between the average value and the parameter standard deviation; The batteries to be tested are screened through the parameter error range to determine the preferred batteries whose discharge capacity, charge capacity and actual SOC of the batteries are within the corresponding parameter error range.

5. The method according to claim 4, characterized in that The method further comprises: The preferred batteries are sorted according to the discharge capacity, the charge capacity and the actual SOC of the battery, and the preferred batteries are divided into groups according to the sorting results.

6. A consistency detection system during battery cycling, characterized in that: The system comprises: A detection module is used to detect the weight and internal resistance of the target battery and select the battery to be tested based on the detection results; A test module, used to set a test environment, perform a charge-discharge cycle test on the battery to be tested, and record the discharge capacity, charge capacity and actual SOC of the battery in the later cycle of the charge-discharge cycle test; A calculation module, used to calculate the corresponding parameter standard deviation based on the discharge capacity, the charge capacity and the actual SOC of the battery, respectively, wherein the parameter standard deviation includes: a discharge capacity standard deviation, a charge capacity standard deviation and a battery actual SOC standard deviation; A screening module is used to determine a parameter error range based on the parameter standard deviation, screen the batteries to be tested through the parameter error range, and determine a preferred battery for consistency grouping.

7. The system according to claim 6, characterized in that The system further comprises: A charging module, used to set the ambient temperature and current size, charge the battery to be tested with a constant current, and switch to constant voltage charging after the battery to be tested is charged to a preset value until the battery to be tested is fully charged; The discharge module is used to discharge the fully charged battery to be tested at a constant current until the battery voltage reaches a cut-off voltage.

8. The system according to claim 7, characterized in that The system further comprises: The second calculation module is used to calculate the capacity value of the battery to be tested to reach the rated capacity of the discharge capacity based on the discharge capacity, calculate the ratio of the capacity value to the discharge capacity, and obtain the actual SOC of the battery.

9. An electronic device comprising a processor and a memory; The processor is connected to the memory; The memory is used to store executable program code; The processor runs a program corresponding to the executable program code by reading the executable program code stored in the memory, so as to execute the method according to any one of claims 1 to 5.

10. A computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the method according to any one of claims 1 to 5.

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