CN114371412A - Method, device and storage medium for testing the maximum current of a rechargeable battery - Google Patents

Abstract

The invention discloses a method and a device for testing the maximum current of a rechargeable battery and a storage medium. The method for testing the maximum current of the rechargeable battery comprises the following steps: under the condition that a rechargeable battery is in a preset charge state, controlling the rechargeable battery to be charged or discharged according to a preset pulse current until the state parameter of the rechargeable battery meets a cut-off condition; reassigning the preset pulse current according to the relative relation between the pulse charging and discharging time and the first preset time; repeating the steps of charging or discharging the rechargeable battery according to the reassigned preset pulse current, and re-determining the relative relationship between the pulse charging and discharging time and the first preset time until the relative relationship changes; and determining the maximum current as the preset pulse current assigned last time or the preset pulse current before the last assignment. The scheme of the invention improves the automation degree of the test, the simplicity and the cleanliness of the process and the accuracy of the result.

Description

Method, device and storage medium for testing the maximum current of a rechargeable battery

technical field

Embodiments of the present invention relate to battery testing technology, and in particular, to a method, device and storage medium for testing the maximum current of a rechargeable battery.

Background technique

As a common reference test for evaluating the pulse and dynamic performance of rechargeable batteries, Imax test has an extremely important position in the development process of rechargeable batteries.

In the actual process of such testing, there is often no clear testing method or testing process, and many steps are required for human intervention. This traditional method is time-consuming and labor-intensive, and the results are inaccurate.

SUMMARY OF THE INVENTION

The present invention provides a method, device and storage medium for testing the maximum current of a rechargeable battery, so as to improve the degree of automation, accuracy and simplicity.

In a first aspect, an embodiment of the present invention provides 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 according to The preset pulse current is charged or discharged until the state parameter of the rechargeable battery meets the cut-off condition; according to the relative relationship between the pulse charging and discharging time and the first preset time, the preset pulse current is reassigned; according to the reassignment Repeat the steps of charging or discharging the rechargeable battery with the subsequent preset pulse current, and re-determine the relative relationship between the pulse charging and discharging time and the first preset time, until the relative relationship changes; determine The maximum current is the preset pulse current of the previous assignment or the preset pulse current before the previous assignment.

Optionally, re-assign the preset pulse current according to the relative relationship between the pulse charging and discharging time and the first preset time, including:

Determine whether the pulse charge and discharge time is greater than or equal to the first preset time, if so, make the preset pulse current equal to the value of the original preset pulse current plus a preset change, otherwise make the preset pulse current The current is equal to the value of the original preset pulse current minus the preset variation.

Optionally, after the relative relationship is changed, it also includes:

After making the preset change amount equal to half of the original preset change amount, return to the first step.

Optionally, before controlling the rechargeable battery to charge or discharge according to the preset pulse current, the method further includes:

The preset change amount is determined according to precision requirements.

Optionally, determining that the maximum current is the preset pulse current of the previous assignment or the preset pulse current before the previous assignment, including:

If the previously determined relative relationship is that the pulse charge and discharge time is greater than or equal to a first preset time, output the maximum current as the preset pulse current;

If the previously determined relative relationship is that the pulse charging and discharging time is less than the first preset time, the maximum current is output as the preset pulse current before the last assignment.

Optionally, before adjusting the rechargeable battery to a preset state of charge, the method further includes: calibrating the charge and discharge capacity of the rechargeable battery.

Optionally, after performing capacity calibration on the rechargeable battery, the method further includes:

adjusting the rechargeable battery to a preset state of charge, wherein the rechargeable battery has different maximum currents in different states of charge;

The rechargeable battery is left to stand for a second preset time.

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

In a second aspect, an embodiment of the present invention further provides a device for testing the maximum current of a rechargeable battery. The device for testing 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 charging and discharging module is used to control the rechargeable battery to charge or discharge according to the preset pulse current when the rechargeable battery is in the preset state of charge, until the state parameter of the rechargeable battery meets the cut-off condition; the assignment module is used for According to the relative relationship between the pulse charging and discharging time and the first preset time, the preset pulse current is re-assigned; the relative relationship determination module is used for repeating the rechargeable battery according to the re-assigned preset pulse current. step of charging or discharging, and re-determine the relative relationship between the time of pulse charging and discharging and the first preset time until the relative relationship changes; the maximum current determination module is used to determine that the maximum current is the value of the previous assignment. The preset pulse current or the preset pulse current before the previous assignment.

In a third aspect, an embodiment of the present invention further provides a computer-readable storage medium storing a computer program, which implements the method for testing the maximum current of a rechargeable battery according to any one of the first aspect when the computer program is executed.

In the method, device and storage medium for testing the maximum current of a rechargeable battery provided by the embodiments of the present invention, charging or discharging is performed with a preset pulse current in a preset state of charge until the rechargeable battery meets the cut-off condition, and then the pulse charge and discharge are determined. The relative relationship between the time and the first preset time, the preset pulse current is re-assigned according to the relative relationship, and the steps of charging or discharging the rechargeable battery are repeated according to the re-assigned preset pulse current, and re- Determine the relative relationship between the time of pulse charging and discharging 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 of the previous assignment or the value before the previous assignment. The preset pulse current realizes the programmed determination of the maximum current of the rechargeable battery, the steps are simple and convenient for automatic implementation, solve the problem of complicated methods in the maximum current test of the rechargeable battery, and improve the degree of automation, accuracy and simplicity.

Description of drawings

1 is a schematic flowchart of a method for testing the maximum current of a rechargeable battery according to an embodiment of the present invention;

2 is a schematic flowchart of another method for testing the maximum current of a rechargeable battery according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a device for testing the maximum current of a rechargeable battery according to an embodiment of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention. In addition, it should be noted that, for the convenience of description, the drawings only show some but not all structures related to the present invention.

The embodiment of the present invention provides a method for testing the maximum current of a rechargeable battery. 1 is a schematic flowchart of a method for testing the maximum current of a rechargeable battery according to an embodiment of the present invention. Referring to FIG. 1, the method for testing the maximum current of a rechargeable battery includes:

S101. When the rechargeable battery is in a preset state of charge, control the rechargeable battery to charge or discharge according to a preset pulse current until the state parameter of the rechargeable battery satisfies the cut-off condition.

Specifically, since the maximum current of the rechargeable battery may be different under different state-of-charge adjustments, it is necessary to adjust the state of charge of the rechargeable battery to the preset state of charge according to actual needs before performing the maximum current test, and then make further testing. When the rechargeable battery is in a preset nuclear power state, a charging and discharging device can be used to control the rechargeable battery to continuously charge or discharge with a preset pulse current until the state parameters of the rechargeable battery meet the cut-off condition. , the charge and discharge current is always kept equal to the preset pulse current, and the state parameters can include battery voltage, battery capacity and state of charge.

S102 , re-assign the preset pulse current according to the relative relationship between the pulse charging and discharging time and the first preset time.

Specifically, the pulse charging time is the duration of charging or discharging the rechargeable battery according to the preset pulse 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 of the rechargeable battery, the capacity, and the factory requirements of the rechargeable battery, and can be obtained by experiments. After the state parameter of the rechargeable battery satisfies the cut-off condition, the relative relationship between the pulse charging and discharging time in step S101 and the first preset time is compared, and the relative relationship may include greater than or equal to and less than. If the time of pulse charging and discharging is greater than or equal to the first preset time, it indicates that the current of pulse charging or discharging is small, and the preset pulse current at this time is less than the actual pulse current of the rechargeable battery, so it is necessary to adjust the value of the preset pulse current. Make appropriate additions. If the time of pulse charging and discharging is less than the first preset time, it indicates that the current of pulse charging or discharging is too large, and the preset pulse current at this time is greater than or equal to the actual pulse current of the rechargeable battery, so it is necessary to adjust the value of the preset pulse current. appropriate reduction.

S103. Repeat the step of charging or discharging the rechargeable battery according to the reassigned preset pulse current, and re-determine the relative relationship between the pulse charging and discharging time and the first preset time until the relative relationship changes.

Specifically, the rechargeable battery is adjusted to a preset state of charge again, and the preset state of charge is the same as the preset state of charge in step S101. The rechargeable battery is then controlled to be charged or discharged according to the reassigned preset pulse current until the state parameter of the rechargeable battery satisfies the cut-off condition. Then compare and re-determine the relative relationship between the pulse charging and discharging time and the first preset time. If the relative relationship changes from greater than or equal to less than or from less than to greater than or equal to, enter the next step, otherwise, according to the relative relationship determined this time After the relationship is re-assigned to the preset pulse current again, this step is repeated until the relative relationship changes.

S104. Determine that the maximum current is the preset pulse current of the previous assignment or the preset pulse current before the previous assignment.

Specifically, if the previously determined relative relationship is that the time of pulse charging and discharging 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 previous assignment and the preset pulse current before the previous assignment. between the values, the maximum current is determined to be the preset pulse current before the previous assignment. If the relative relationship determined last time is that the time of pulse charge and discharge is greater than or equal to the first preset time, it indicates that the value of the maximum current is the difference between the value of the preset pulse current after the previous assignment and the preset pulse current before the previous assignment. value, the maximum current is determined to be the preset pulse current after the previous assignment. This ensures that the determined maximum current value does not exceed the actual maximum current, thereby ensuring the safe and stable operation of the battery.

In the method for testing the maximum current of a rechargeable battery provided in this embodiment, charging or discharging is performed with a preset pulse current in a preset state of charge until the rechargeable battery meets the cut-off condition, and then the time of pulse charge and discharge is determined to be the same as the first preset pulse current. Set the relative relationship of 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 pulse charging and discharging time and the first preset pulse current. Set the relative relationship of time until the relative relationship changes. At this time, it is determined that the maximum current is the preset pulse current of the previous assignment or the preset pulse current before the previous assignment, and the programmed determination of the maximum current of the rechargeable battery is realized. The steps are simple and convenient for automatic implementation, which solves the problems of complicated methods and low degree of automation in the maximum current test of the rechargeable battery, and improves the accuracy and simplicity of the test.

2 is a schematic flowchart of another method for testing the maximum current of a rechargeable battery according to an embodiment of the present invention. Referring to FIG. 2 , the method for testing the maximum current of a rechargeable battery includes:

S201. Determine a preset change amount according to a precision requirement.

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 requirements for the accuracy of the test results of the maximum current. Exemplarily, the preset change amount may be 0.1A, and the error of the maximum current may be controlled within 0.1A.

S202 , calibrating the charge and discharge capacity of the rechargeable battery.

Specifically, at a preset temperature, a battery capacity calibration device is used to calibrate the charging capacity and the discharging capacity of the rechargeable battery respectively, so as to accurately determine the charging capacity and discharging capacity of the rechargeable battery, and improve the cut-off conditions of the pulse discharge and pulse charging in the subsequent steps. accuracy. Wherein, the rechargeable battery may be a lithium-ion battery. Exemplarily, the rechargeable battery can be charged and discharged at 1C for five cycles, the average value of the charging capacity determined by the last three cycles of charging and discharging is taken as the calibration value of the charging capacity, and the average value of the discharging capacity determined by the last three cycles of charging and discharging is taken as the discharge capacity. The nominal value of the capacity.

S203. Adjust the rechargeable battery to a preset state of charge.

Among them, the maximum current of the rechargeable battery is different in different states of charge. Specifically, a charging and discharging device is used to charge or discharge the rechargeable battery, and the state of charge of the rechargeable battery is adjusted to a preset state of charge. The preset state of charge is selected by the tester according to actual needs to test different states of charge. The maximum current for charging the battery. Illustratively, the preset state of charge may be 50%.

S204, leaving the rechargeable battery to stand for a second preset time.

Specifically, the rechargeable battery is left to stand for a second preset time, so that the rechargeable battery is consistent with the preset temperature, and the influence of errors caused by charging and discharging heating is reduced. Exemplarily, the preset temperature may be 25 degrees Celsius.

S205 , when the rechargeable battery is in a 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 satisfies the cut-off condition.

Specifically, if the charging maximum current test needs to be performed, the rechargeable battery is charged according to the preset pulse current until the state parameter of the rechargeable battery satisfies the cut-off condition. If the discharge maximum current test needs to be performed, the rechargeable battery is discharged according to the preset pulse current until the state parameters of the rechargeable battery meet the cut-off condition. The cut-off condition of the charging maximum current test may 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 of the discharge maximum current test may 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 battery meet the cut-off condition, the duration of charging or discharging is recorded, which is recorded as the time of pulse charging and discharging.

S206: Determine whether the pulse charging and discharging time is greater than or equal to the first preset time, and if so, set the preset pulse current equal to the value of the original preset pulse current plus the preset change, otherwise make the preset pulse current equal to the original preset pulse The value of the current minus the preset change amount.

Specifically, it is determined whether the time of pulse charging and discharging is greater than or equal to the first preset time, and if so, it indicates that the current used for pulse charging or discharging may be too small, and the preset pulse current at this time 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 that the preset pulse current is equal to the value of the original preset pulse current plus the 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, the value of the preset pulse current needs to be appropriately reduced, so the preset pulse current is equal to the original pulse current. The value of the preset pulse current minus the preset variation.

S207. Repeat the step of charging or discharging the rechargeable battery according to the reassigned preset pulse current, and re-determine the relative relationship between the pulse charging and discharging time and the first preset time until the relative relationship changes.

Specifically, the rechargeable battery is controlled to be charged or discharged according to the newly assigned preset pulse current, and whether charging or discharging here needs to be consistent with step S205. Then determine the relative relationship between the charging and discharging 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, from greater than or equal to less than, or from less than to greater than equal.

S208 , if the previously determined relative relationship is that the pulse charging and discharging time is greater than or equal to the first preset time, output the maximum current as the preset pulse current.

Specifically, if the last relative relationship changes and the last determined relative relationship is that the time of pulse charge and discharge is greater than or equal to the first preset time, it means that the maximum current value is the difference between the previously determined preset pulse current and the last determined pulse current. Between the previous preset pulse currents, at this time, the preset pulse current determined previously is determined as the maximum current, which 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 of the rechargeable battery is less than the maximum current during operation, which greatly reduces the risk of spontaneous combustion caused by excessive current.

S209 , if the previously determined relative relationship is that the pulse charging and discharging time is less than the first preset time, the output maximum current is the preset pulse current before the last assignment.

Specifically, if the last relative relationship changes and the last determined relative relationship is that the time of pulse charge and discharge is less than the first preset time, it means that the maximum current value is the preset pulse current before the last determination and the last determined pulse current. Between the preset pulse currents, the preset pulse current before the previous determination is determined as the maximum current, which 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 of the rechargeable battery is less than the maximum current during operation, which greatly reduces the risk of spontaneous combustion caused by excessive current.

In the method for testing the maximum current of a rechargeable battery provided in this embodiment, the preset pulse current can be reassigned according to the relative relationship between the pulse charging and discharging time and the first preset time, and then the steps of charging or discharging the rechargeable battery are repeated. , and re-determine the relative relationship between the pulse charging and discharging time and the first preset time until the relative relationship changes, at which time it is determined that the maximum current is the preset pulse current of the previous assignment or the preset pulse before the previous assignment The current realizes the programmed determination of the maximum current of the rechargeable battery. The steps are simple and convenient for automatic implementation. The preset variation can be set according to the demand for accuracy, which can improve the accuracy and applicability of the test results.

Optionally, continuing to refer to FIG. 2 , in step S201 , a preset change amount larger than the actual demand may be set. After the relative relationship changes, the preset change amount may be further reduced, and then the process returns to step S203 to re-determine the maximum current according to the preset change amount at this time and the preset pulse current at this time. The method of reducing the preset change amount may be to set the preset change amount to be half of the original preset change amount. 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 to setting a smaller preset change at the beginning, saving test time.

The embodiment of the present invention also provides a device for testing the maximum current of a rechargeable battery. FIG. 3 is a schematic structural diagram of a test device for the maximum current of a rechargeable battery according to an embodiment of the present invention. Referring to FIG. 3 , the test device includes 300 : a pulse charge and discharge module 301 , an assignment module 302 , a relative relationship determination module 303 and a maximum current The determination module 304; the pulse charge and discharge module 301 is used to control the rechargeable battery to charge or discharge according to the preset pulse current when the rechargeable battery is in the preset state of charge, until the state parameter of the rechargeable battery satisfies the cut-off condition; the assignment module 302 for re-assigning the preset pulse current according to the relative relationship between the time of pulse charging and discharging and the first preset time; the relative relationship determining module 303 is used to repeatedly charge or discharge the rechargeable battery according to the re-assigned preset pulse current step, and re-determine the relative relationship between the pulse charging and discharging time and the first preset time until the relative relationship changes; the maximum current determination module 304 is used to determine that the maximum current is the preset pulse current of the previous assignment or the previous assignment The previous preset pulse current.

Embodiments of the present invention also provide a computer-readable storage medium. A computer-readable storage medium storing a computer program, when the computer program is executed, the method for testing the maximum current of any rechargeable battery as described above is implemented.

The method, device, and storage medium for testing the maximum current of a rechargeable battery provided in this embodiment can re-assign the preset pulse current according to the relative relationship between the pulse charge and discharge time and the first preset time, and then repeat the process of the rechargeable battery. Steps of charging or discharging, and re-determine the relative relationship between the pulse charging and discharging time and the first preset time, until the relative relationship changes, at which time it is determined that the maximum current is the preset pulse current of the previous assignment or the previous assignment The previous preset pulse current realizes the programmatic determination of the maximum current of the rechargeable battery. The steps are simple and convenient for automatic implementation. The preset variation can be set according to the requirements for accuracy, which can improve the accuracy and applicability of the test results.

The above product can execute the method provided by any embodiment of the present invention, and has corresponding functional modules and beneficial effects for executing the method.

Note that the above are only preferred embodiments of the present invention and applied technical principles. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, 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, and can also include more other equivalent embodiments without departing from the concept of the present invention. The scope is determined by the scope of the appended claims.

Claims (10)

1. a method for testing the maximum current of a rechargeable battery, comprising: When the rechargeable battery is in the preset state of charge, controlling the rechargeable battery to charge or discharge according to the preset pulse current until the state parameter of the rechargeable battery satisfies the cut-off condition; reassigning the preset pulse current according to the relative relationship between the pulse charging and discharging time and the first preset time; Repeat the step of charging or discharging the rechargeable battery according to the reassigned preset pulse current, and re-determine the relative relationship between the pulse charging and discharging time and the first preset time, until the relative relationship occurs Variety; It is determined that the maximum current is 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 a 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 the first preset time, comprising: Determine whether the pulse charge and discharge time is greater than or equal to the first preset time, if so, make the preset pulse current equal to the value of the original preset pulse current plus a preset change, otherwise make the preset pulse current The current is equal to the value of the original preset pulse current minus the preset variation. 3. The method for testing the maximum current of a rechargeable battery according to claim 2, wherein after the relative relationship changes, the method further comprises: After making the preset change amount equal to half of the original preset change amount, return to the first step. 4. The method for testing the maximum current of a rechargeable battery according to claim 2, wherein before controlling the rechargeable battery to charge or discharge according to a preset pulse current, the method further comprises: The preset change amount is determined according to precision requirements. 5. The method for testing the maximum current of a rechargeable battery according to claim 1, wherein determining that the maximum current is the preset pulse current of the previous assignment or the preset pulse current before the previous assignment ,include: If the previously determined relative relationship is that the pulse charge and discharge time is greater than or equal to a first preset time, output the maximum current as the preset pulse current; If the previously determined relative relationship is that the pulse charging and discharging time is less than the first preset time, the maximum current is output as the preset pulse current before the last assignment. 6. The method for testing the maximum current of a rechargeable battery according to claim 1, wherein before adjusting the rechargeable battery to a preset state of charge, the method further comprises: The charging and discharging capacity of the rechargeable battery is calibrated. 7. The method for testing the maximum current of a rechargeable battery according to claim 6, characterized in that, after the rechargeable battery is subjected to charge-discharge capacity calibration, the method further comprises: adjusting the rechargeable battery to a preset state of charge, wherein the rechargeable battery has different maximum currents in different states of charge; The rechargeable battery is left to stand for a second preset time. 8 . The method for testing the maximum current of a rechargeable battery according to claim 1 , wherein the cut-off condition comprises: the voltage reaches a preset voltage value or the capacity reaches a preset capacity value. 9 . 9. A test device for the maximum current of a rechargeable battery, comprising: a pulse charging and discharging module, 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 satisfies the cut-off condition; an assignment module, configured to re-assign the preset pulse current according to the relative relationship between the pulse charging and discharging time and the first preset time; A relative relationship determination module, configured to 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 pulse charging and discharging time and the first preset time , until the relative relationship changes; A maximum current determination module, configured to determine that the maximum current is the preset pulse current of the previous assignment or the preset pulse current before the previous assignment. 10. A computer-readable storage medium storing a computer program, wherein when the computer program is executed, the method for testing the maximum current of a rechargeable battery according to any one of claims 1-8 is implemented.

Images