Testing Method, Device and Storage Medium for Maximum Current of a Rechargeable Battery

Abstract

The present invention discloses a method, device, and storage medium for testing the maximum current of a rechargeable battery. The method for testing the maximum current of a rechargeable battery includes: when the rechargeable battery is in a preset state of charge, controlling the rechargeable battery to be charged or discharged according to a preset pulse current until the state parameter of the rechargeable battery meets the cut-off condition; reassigning a value to the preset pulse current according to the relative relationship between the time of pulse charge and discharge and a first preset time; repeating the step of charging or discharging the rechargeable battery according to the preset pulse current after the value is reassigned, and re-determining the relative relationship between the time of pulse charge and discharge and the first preset time until the relative relationship changes; determining the maximum current as the preset pulse current assigned in the previous time or the preset pulse current before the previous assignment. The solution of the present invention improves the degree of automation of the test, the simplicity of the process, and the accuracy of the result.

Description

Technical Field

[0001] Embodiments of the present invention relate to battery testing technologies, and in particular, to a method, apparatus, and storage medium for testing the maximum current of a rechargeable battery. Background Art

[0002] As a common reference test for evaluating the pulse and kinetic performance of rechargeable batteries, Imax testing plays an extremely important role in the development process of rechargeable batteries.

[0003] In the actual process of conducting such tests, there is often no clear test method or test process, and there are many steps that require manual intervention. This traditional method is time-consuming and laborious, and the results are also inaccurate. Summary of the Invention

[0004] The present invention provides a method, apparatus, and storage medium for testing the maximum current of a rechargeable battery to improve the degree of automation, accuracy, and simplicity.

[0005] In a first aspect, embodiments of the present invention provide a method for testing the maximum current of a rechargeable battery. The method for testing the maximum current of a rechargeable battery includes: when the rechargeable battery is in a preset state of charge, controlling the rechargeable battery to charge or discharge according to a preset pulse current until the state parameter of the rechargeable battery meets a cut-off condition; reassigning a value to the preset pulse current according to the relative relationship between the time of pulse charge and discharge and a first preset time; repeating the step of charging or discharging the rechargeable battery with the reassigned preset pulse current and re-determining the relative relationship between the time of pulse charge and discharge and the first preset time until the relative relationship changes; determining the maximum current as the preset pulse current assigned in the previous time or the preset pulse current before the previous assignment.

[0006] Optionally, reassigning a value to the preset pulse current according to the relative relationship between the time of pulse charge and discharge and a first preset time includes:

[0007] Judging whether the time of pulse charge and discharge is greater than or equal to the first preset time. If so, making the preset pulse current equal to the value of the original preset pulse current plus a preset change amount; otherwise, making the preset pulse current equal to the value of the original preset pulse current minus the preset change amount.

[0008] Optionally, after the relative relationship changes, it further includes:

[0009] Making the preset change amount equal to half of the original preset change amount, and then returning to the first step.

[0010] Optionally, before controlling the rechargeable battery to charge or discharge according to a preset pulse current, it further includes:

[0011] Determine the preset change amount according to the accuracy requirement.

[0012] Optionally, determining the maximum current as the preset pulse current assigned last time or the preset pulse current before the last assignment includes:

[0013] If the relative relationship determined last time is that the time of the pulse charge and discharge is greater than or equal to the first preset time, then output the maximum current as the preset pulse current;

[0014] If the relative relationship determined last time is that the time of the pulse charge and discharge is less than the first preset time, then output the maximum current as the preset pulse current before the last assignment.

[0015] Optionally, before adjusting the rechargeable battery to the preset state of charge, it further includes: calibrating the charge and discharge capacity of the rechargeable battery.

[0016] Optionally, after calibrating the capacity of the rechargeable battery, it further includes:

[0017] Adjust the rechargeable battery to the preset state of charge, wherein the maximum current of the rechargeable battery is different under different states of charge;

[0018] Let the rechargeable battery stand for a second preset time.

[0019] Optionally, the cut-off condition includes: the voltage reaches the preset voltage value or the capacity reaches the preset capacity value.

[0020] In a second aspect, an embodiment of the present invention further provides a test device for the maximum current of a rechargeable battery. The test device for the maximum current of a rechargeable battery includes: a pulse charge and discharge module, an assignment module, a relative relationship determination module, and a maximum current determination module. The pulse charge and discharge module is used to control the rechargeable battery to charge or discharge according to a preset pulse current when the rechargeable battery is in a preset state of charge until the state parameter of the rechargeable battery meets the cut-off condition; the assignment module is used to re-assign the preset pulse current according to the relative relationship between the time of the pulse charge and discharge and the first preset time; the relative relationship determination module is used to repeat the steps of charging or discharging the rechargeable battery according to the re-assigned preset pulse current and re-determine the relative relationship between the time of the pulse charge and discharge and the first preset time until the relative relationship changes; the maximum current determination module is used to determine the maximum current as the preset pulse current assigned last time or the preset pulse current before the last assignment.

[0021] In a third aspect, an embodiment of the present invention further provides a computer-readable storage medium storing a computer program, which when executed implements the method for testing the maximum current of a rechargeable battery as described in any one of the first aspects.

[0022] The method, device and storage medium for testing the maximum current of a rechargeable battery provided by the embodiments of the present invention charge or discharge at a preset pulse current under a preset state of charge until the rechargeable battery meets the cut-off condition, and then judge the relative relationship between the time of pulse charge and discharge and a first preset time. Reassign the preset pulse current according to the relative relationship, repeat the steps of charging or discharging the rechargeable battery according to the reassigned preset pulse current, and re-determine the relative relationship between the time of pulse charge and discharge and the first preset time until the relative relationship changes. At this time, the maximum current is determined to be the preset pulse current assigned last time or the preset pulse current before the last assignment, realizing the programmed determination of the maximum current of the rechargeable battery. The steps are simple, convenient for automatic implementation, solve the problem of cumbersome methods in the test of the maximum current of rechargeable batteries, and improve the degree of automation, accuracy and simplicity. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic flow chart of a method for testing the maximum current of a rechargeable battery provided by an embodiment of the present invention;

[0024] Figure 2 is a schematic flow chart of another method for testing the maximum current of a rechargeable battery provided by an embodiment of the present invention;

[0025] Figure 3 is a schematic structural diagram of a device for testing the maximum current of a rechargeable battery provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that for the sake of description, only parts related to the present invention are shown in the drawings rather than all the structures.

[0027] An embodiment of the present invention provides a method for testing the maximum current of a rechargeable battery. Figure 1 is a schematic flow chart of a method for testing the maximum current of a rechargeable battery provided by an embodiment of the present invention. Refer to Figure 1 The method for testing the maximum current of a rechargeable battery includes:

[0028] S101. When the rechargeable battery is in a preset state of charge, control the rechargeable battery to charge or discharge according to a preset pulsed current until the state parameters of the rechargeable battery meet the cut-off condition.

[0029] Specifically, since the maximum current of the rechargeable battery may vary under different state-of-charge regulations, before performing the maximum current test, the state of charge of the rechargeable battery needs to be adjusted to the preset state of charge according to actual requirements, and then further tests can be carried out. When the rechargeable battery is in the preset nuclear state, a charge and discharge device can be used to control the rechargeable battery to continuously charge or discharge at a preset pulsed current until the state parameters of the rechargeable battery meet the cut-off condition. Among them, during the charging or discharging process, the charge and discharge current is always kept equal to the preset pulsed current. The state parameters can include battery voltage, battery capacity, and state of charge.

[0030] S102. Reassign a value to the preset pulsed current according to the relative relationship between the time of pulsed charge and discharge and the first preset time.

[0031] Specifically, the time of pulsed charging is the duration during which the rechargeable battery charges or discharges at the preset pulsed current in step S101. The first preset time is a preset time determination value set in advance by the tester according to the preset state of charge, capacity of the rechargeable battery, and the factory requirements of the rechargeable battery, etc., and can be obtained through experiments. After the state parameters of the rechargeable battery meet the cut-off condition, compare the relative relationship between the time of pulsed charge and discharge in step S101 and the first preset time. The relative relationship can include greater than or equal to and less than. If the time of pulsed charge and discharge is greater than or equal to the first preset time, it indicates that the current of pulsed charging or discharging is too small. At this time, the preset pulsed current is less than the actual pulsed current of this rechargeable battery, so the value of the preset pulsed current needs to be appropriately increased. If the time of pulsed charge and discharge is less than the first preset time, it indicates that the current of pulsed charging or discharging is too large. At this time, the preset pulsed current is greater than or equal to the actual pulsed current of this rechargeable battery, so the value of the preset pulsed current needs to be appropriately decreased.

[0032] S103. Repeat the steps of charging or discharging the rechargeable battery according to the reassigned preset pulsed current, and re-determine the relative relationship between the time of pulsed charge and discharge and the first preset time until the relative relationship changes.

[0033] Specifically, the rechargeable battery is adjusted again to the preset state of charge, which is the same as the preset state of charge in step S101. Then, control the rechargeable battery to charge or discharge according to the preset pulse current after re - assignment until the state parameters of the rechargeable battery meet the cut - off condition. Then, compare the relative relationship between the re - determined pulse charge - discharge time and the first preset time again. If the relative relationship changes from greater than or equal to to less than or from less to greater than or equal to, proceed to the next step; otherwise, re - assign the preset pulse current according to the relative relationship determined this time and repeat this step until the relative relationship changes.

[0034] S104. Determine that the maximum current is the preset pulse current assigned last time or the preset pulse current before the last assignment.

[0035] Specifically, if the relative relationship determined last time is that the pulse charge - discharge time is less than the first preset time, it indicates that the value of the maximum current is between the value of the preset pulse current after the last assignment and the value of the preset pulse current before the last assignment. Then, determine that the maximum current is the preset pulse current before the last assignment. If the relative relationship determined last time is that the pulse charge - discharge time is greater than or equal to the first preset time, it indicates that the value of the maximum current is between the value of the preset pulse current after the last assignment and the value of the preset pulse current before the last assignment. Then, determine that the maximum current is the preset pulse current after the last assignment. This ensures that the determined maximum current value does not exceed the actual maximum current, guaranteeing the safe and stable operation of the battery.

[0036] The method for testing the maximum current of the rechargeable battery provided in this embodiment charges or discharges the rechargeable battery with a preset pulse current under a preset state of charge until the rechargeable battery meets the cut - off condition. Then, judge the relative relationship between the pulse charge - discharge time and the first preset time, re - assign the preset pulse current according to the relative relationship, repeat the steps of charging or discharging the rechargeable battery according to the re - assigned preset pulse current, and re - determine the relative relationship between the pulse charge - discharge time and the first preset time until the relative relationship changes. At this time, it is determined that the maximum current is the preset pulse current assigned last time or the preset pulse current before the last assignment, realizing the programmed determination of the maximum current of the rechargeable battery. The steps are simple, convenient for automatic implementation, solve the problems of cumbersome method and low automation degree in the test of the maximum current of the rechargeable battery, and improve the accuracy and simplicity of the test.

[0037] Figure 2 is a schematic flowchart of another method for testing the maximum current of a rechargeable battery provided by an embodiment of the present invention. Referring to Figure 2 , the method for testing the maximum current of a rechargeable battery includes:

[0038] S201. Determine the preset change amount according to the accuracy requirement.

[0039] Specifically, the tester can determine the preset variation according to the accuracy requirement of the test result of the maximum current. Different types of rechargeable batteries have different accuracy requirements for the test results of the maximum current. The smaller the preset variation, the higher the result accuracy, and at the same time, the number of test cycles and time will increase accordingly. Exemplarily, the preset variation can be 0.1 A, and the error of the maximum current can be controlled within 0.1 A.

[0040] S202. Calibrate the charge-discharge capacity of the rechargeable battery.

[0041] Specifically, at the preset temperature, use a battery capacity calibration device to calibrate the charge capacity and discharge capacity of the rechargeable battery respectively, accurately determine the charge capacity and discharge capacity of the rechargeable battery, and improve the accuracy of the cut-off conditions for pulse discharge and pulse charging in the subsequent steps. Among them, the rechargeable battery can be a lithium-ion battery. Exemplarily, the rechargeable battery can be charged and discharged at 1C for five cycles, and the average value of the charge capacity determined from the last three cycles of charge and discharge is taken as the calibration value of the charge capacity, and the average value of the discharge capacity determined from the last three cycles of charge and discharge is taken as the calibration value of the discharge capacity.

[0042] S203. Adjust the rechargeable battery to the preset state of charge.

[0043] Among them, the maximum current of the rechargeable battery is different under different states of charge. Specifically, use a charge-discharge device to charge or discharge the rechargeable battery, and adjust the state of charge of the rechargeable battery to the preset state of charge. The preset state of charge is selected by the tester according to actual needs to test the maximum current of the rechargeable battery under different states of charge. Exemplarily, the preset state of charge can be 50%.

[0044] S204. Leave the rechargeable battery standing for a second preset time.

[0045] Specifically, leave the rechargeable battery standing for a second preset time to make the rechargeable battery consistent with the preset temperature and reduce the error influence caused by charge-discharge heating. Exemplarily, the preset temperature can be 25 degrees Celsius.

[0046] S205. When the rechargeable battery is in the preset state of charge, control the rechargeable battery to charge or discharge according to the preset pulse current until the state parameter of the rechargeable battery meets the cut-off condition.

[0047] Specifically, if a maximum charging current test is required, the rechargeable battery is charged according to a preset pulse current until the state parameters of the rechargeable battery meet the cut-off condition. If a maximum discharging current test is required, the rechargeable battery is discharged according to a preset pulse current until the state parameters of the rechargeable battery meet the cut-off condition. The cut-off condition for the maximum charging current test can be that the voltage of the rechargeable battery reaches the upper limit voltage or the capacity of the rechargeable battery reaches the upper limit capacity. The cut-off condition for the maximum discharging current test can be that the voltage of the rechargeable battery reaches the lower limit voltage or the capacity of the rechargeable battery reaches the lower limit capacity. When the state parameters of the rechargeable battery meet the cut-off condition, record the duration of charging or discharging, which is denoted as the time of pulse charge and discharge.

[0048] S206. Determine whether the time of pulse charge and discharge is greater than or equal to a first preset time. If so, set the preset pulse current to the value of the original preset pulse current plus a preset change amount; otherwise, set the preset pulse current to the value of the original preset pulse current minus a preset change amount.

[0049] Specifically, determine whether the time of pulse charge and discharge is greater than or equal to a first preset time. If so, it indicates that the current used for pulse charging or discharging may be too small. At this time, the preset pulse current is less than or equal to the actual pulse current of the rechargeable battery. Therefore, it is necessary to appropriately increase the value of the preset pulse current, so set the preset pulse current to the value of the original preset pulse current plus a preset change amount. Otherwise, it indicates that the current used for pulse charging or discharging is too large. At this time, the preset pulse current is greater than the actual pulse current of the rechargeable battery. Therefore, it is necessary to appropriately reduce the value of the preset pulse current, so set the preset pulse current to the value of the original preset pulse current minus a preset change amount.

[0050] S207. Repeat the steps of charging or discharging the rechargeable battery according to the re-assigned preset pulse current, and re-determine the relative relationship between the time of pulse charge and discharge and the first preset time until the relative relationship changes.

[0051] Specifically, control the rechargeable battery to charge or discharge according to the newly assigned preset pulse current. Whether it is charging or discharging here needs to be consistent with step S205. Furthermore, determine the relative relationship between the charge and discharge time and the first preset time. If the relative relationship is the same as the result of the previous judgment, repeat this step until the relative relationship changes, that is, changes from greater than or equal to to less than, or from less than to greater than or equal to.

[0052] S208. If the previously determined relative relationship is that the time of pulse charge and discharge is greater than or equal to the first preset time, output the maximum current as the preset pulse current.

[0053] Specifically, if the previous relative relationship changes and the previously determined relative relationship is that the pulse charge-discharge time is greater than or equal to the first preset time, it indicates that the maximum current value is between the previously determined preset pulse current and the preset pulse current before the previous determination. At this time, determining the previously determined preset pulse current as the maximum current can ensure that the error is within the preset variation, and the determined maximum current value will not exceed the actual maximum current value, ensuring that the current in the rechargeable battery during operation is less than the maximum current, greatly reducing the risks such as spontaneous combustion caused by excessive current.

[0054] S209. If the previously determined relative relationship is that the pulse charge-discharge time is less than the first preset time, then output the maximum current as the preset pulse current before the previous assignment.

[0055] Specifically, if the previous relative relationship changes and the previously determined relative relationship is that the pulse charge-discharge time is less than the first preset time, it indicates that the maximum current value is between the preset pulse current before the previous determination and the previously determined preset pulse current. At this time, determining the preset pulse current before the previous determination as the maximum current can ensure that the error is within the preset variation, and the determined maximum current value will not exceed the actual maximum current value, ensuring that the current in the rechargeable battery during operation is less than the maximum current, greatly reducing the risks such as spontaneous combustion caused by excessive current.

[0056] The method for testing the maximum current of the rechargeable battery provided in this embodiment can reassign the preset pulse current according to the relative relationship between the pulse charge-discharge time and the first preset time, and then repeat the steps of charging or discharging the rechargeable battery, and re-determine the relative relationship between the pulse charge-discharge time and the first preset time until the relative relationship changes. At this time, it is determined that the maximum current is the preset pulse current assigned in the previous time or the preset pulse current before the previous assignment, realizing the programmed determination of the maximum current of the rechargeable battery. The steps are simple, convenient for automatic implementation, the preset variation can be set according to the requirement of accuracy, and the accuracy and applicability of the test results can be improved.

[0057] Optionally, continue to refer to Figure 2 , in step S201, a preset variation larger than the actual requirement can be set. And after the relative relationship changes, the preset variation can be further reduced, and then according to the current preset variation and the current preset pulse current, return to step S203 to re-determine the maximum current. Among them, the way to reduce the preset variation can be to set the preset variation to half of the original preset variation. Such a judgment method can quickly narrow the selection range of the maximum current in the early stage of judgment, which can not only improve the test accuracy but also greatly reduce the number of cycles compared with setting a smaller preset variation at the beginning, saving the test time.

[0058] An embodiment of the present invention also provides a test device for the maximum current of a rechargeable battery. Figure 3 It is a schematic structural diagram of a test device for the maximum current of a rechargeable battery provided by an embodiment of the present invention. Refer to Figure 3 , the test device includes: a pulse charge and discharge module 301, an assignment module 302, a relative relationship determination module 303, and a maximum current determination module 304; the pulse charge and discharge module 301 is configured to control the rechargeable battery to charge or discharge according to a preset pulse current when the rechargeable battery is in a preset state of charge until the state parameter of the rechargeable battery meets the cut-off condition; the assignment module 302 is configured to re-assign the preset pulse current according to the relative relationship between the time of pulse charge and discharge and a first preset time; the relative relationship determination module 303 is configured to repeat the steps of charging or discharging the rechargeable battery according to the re-assigned preset pulse current and re-determine the relative relationship between the time of pulse charge and discharge and the first preset time until the relative relationship changes; the maximum current determination module 304 is configured to determine that the maximum current is the preset pulse current assigned last time or the preset pulse current before the last assignment.

[0059] An embodiment of the present invention also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed, it implements the test method for the maximum current of any rechargeable battery as described above.

[0060] The test method, device, and storage medium for the maximum current of the rechargeable battery provided in this embodiment can re-assign the preset pulse current according to the relative relationship between the time of pulse charge and discharge and the first preset time, and then repeat the steps of charging or discharging the rechargeable battery and re-determine the relative relationship between the time of pulse charge and discharge and the first preset time until the relative relationship changes. At this time, it is determined that the maximum current is the preset pulse current assigned last time or the preset pulse current before the last assignment, realizing the programmed determination of the maximum current of the rechargeable battery. The steps are simple, convenient for automatic implementation, and the preset change amount can be set according to the requirement for accuracy, which can improve the accuracy and applicability of the test results.

[0061] The above products can execute the methods provided in any embodiment of the present invention and have the corresponding functional modules and beneficial effects of the executed methods.

[0062] Note that the above is only a preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, re-adjustments, combinations, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for testing the maximum current of a rechargeable battery, characterized in that, Including: When the rechargeable battery is in a preset state of charge, controlling the rechargeable battery to be charged or discharged according to a preset pulse current until the state parameter of the rechargeable battery meets the cut-off condition, where the cut-off condition includes that the capacity reaches a preset capacity value; Reassigning the preset pulse current according to the relative relationship between the time of pulse charge and discharge and a first preset time; Repeating the step of charging or discharging the rechargeable battery according to the preset pulse current after reassigning, and re-determining the relative relationship between the time of pulse charge and discharge and the first preset time until the relative relationship changes; Determining the maximum current as the preset pulse current of the previous assignment or the preset pulse current before the previous assignment.

2. The method for testing the maximum current of the rechargeable battery according to claim 1, wherein, Reassigning the preset pulse current according to the relative relationship between the time of pulse charge and discharge and a first preset time, including: Judging whether the time of pulse charge and discharge is greater than or equal to the first preset time. If so, making the preset pulse current equal to the value of the original preset pulse current plus a preset change amount; otherwise, making the preset pulse current equal to the value of the original preset pulse current minus a preset change amount.

3. The method for testing the maximum current of a rechargeable battery according to claim 2, characterized in that, After the relative relationship changes, further including: Making the preset change amount equal to half of the original preset change amount, and then returning to the first step.

4. The method for testing the maximum current of a rechargeable battery according to claim 2, characterized in that Before controlling the rechargeable battery to be charged or discharged according to the preset pulse current, further including: Determining the preset change amount according to the accuracy requirement.

5. The method for testing the maximum current of a rechargeable battery according to claim 1, characterized in that, Determining the maximum current as the preset pulse current of the previous assignment or the preset pulse current before the previous assignment, including: If the relative relationship determined previously is that the time of pulse charge and discharge is greater than or equal to the first preset time, outputting the maximum current as the preset pulse current; If the relative relationship determined previously is that the time of pulse charge and discharge is less than the first preset time, outputting the maximum current as the preset pulse current before the previous assignment.

6. The test method for the maximum current of a rechargeable battery according to claim 1, characterized in that Before adjusting the rechargeable battery to the preset state of charge, further including: Calibrating the charge and discharge capacity of the rechargeable battery.

7. The test method for the maximum current of the rechargeable battery according to claim 6, wherein After calibrating the charge and discharge capacity of the rechargeable battery, further including: Adjusting the rechargeable battery to the preset state of charge, where the maximum current of the rechargeable battery is different in different states of charge; Letting the rechargeable battery stand for a second preset time.

8. A test device for the maximum current of a rechargeable battery, characterized in that, Including: A pulse charge and discharge module, configured to control the rechargeable battery to be charged or discharged according to a preset pulse current when the rechargeable battery is in a preset state of charge until the state parameter of the rechargeable battery meets the cut-off condition, where the cut-off condition includes that the capacity reaches a preset capacity value; An assignment module, configured to reassign the preset pulse current according to the relative relationship between the time of pulse charge and discharge and a first preset time; A relative relationship determination module, configured to repeat the step of charging or discharging the rechargeable battery according to the preset pulse current after reassigning, and re-determine the relative relationship between the time of pulse charge and discharge and the first preset time until the relative relationship changes; The maximum current determination module is configured to determine that the maximum current is the preset pulse current assigned in the previous time or the preset pulse current before the previous assignment.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed, it implements the test method for the maximum current of the rechargeable battery according to any one of claims 1-7.

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