Battery peak current test method, device, test equipment and storage medium

Abstract

The present invention discloses a battery peak current testing method, device, testing equipment and storage medium. The testing method comprises: determining test parameters of a battery to be tested, wherein the test parameters include a target remaining power and a target pulse duration; determining a reference voltage based on the target remaining power; testing the battery to be tested with the reference voltage as the test voltage and detecting the current after the test duration is equal to a preset test duration to obtain an initial test current; testing the battery to be tested according to the initial test current, the preset current step length and the target pulse duration to obtain the peak current of the battery to be tested under the test parameter test, so that those skilled in the art can locate the initial test current through a reference voltage close to the cut-off voltage of the battery to be tested, the initial test current is closer to the peak current, and compared with the current test method test by randomly selecting the current, the number of tests to obtain the peak current is small, the test cycle is shortened, the test efficiency is improved, and the production efficiency of the battery is finally improved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery testing, and in particular to a battery peak current testing method, device, testing equipment and storage medium. Background Art

[0002] The power performance of pure electric vehicles depends on the charging and discharging capabilities of lithium-ion batteries. The pulse peak current of the battery can evaluate the battery's short-term (10s / 30s / 60s) charging and discharging current limit capabilities under different charge states.

[0003] At present, the test method for battery pulse peak current is the test current method. The test current method randomly selects a current as the initial current for testing. After each test, if the battery voltage does not reach the cut-off voltage, the current is increased and tested again until the battery voltage reaches the cut-off voltage. The current tested is the peak current.

[0004] It can be seen that the current test method requires multiple tests to obtain the peak current, which leads to a long test cycle of the current test method and low test efficiency and production efficiency. Summary of the invention

[0005] The present invention provides a battery peak current testing method, device, testing equipment and storage medium to solve the problem of low efficiency in the battery peak current testing method in the prior art.

[0006] In a first aspect, the present invention provides a battery peak current testing method, comprising:

[0007] Determine test parameters of the battery to be tested, wherein the test parameters include a target remaining power and a target pulse duration;

[0008] determining a reference voltage based on the target remaining power;

[0009] Performing a constant voltage test on the battery to be tested with the reference voltage as the test voltage, and detecting the current after the test time is equal to the preset test time to obtain an initial test current;

[0010] A constant voltage test is performed on the battery to be tested according to the initial test current, the preset current step length, and the target pulse duration to obtain a peak current of the battery to be tested under the test parameter test.

[0011] In a second aspect, the present invention provides a battery peak current testing device, comprising:

[0012] A test parameter determination module, used to determine the test parameters of the battery to be tested, wherein the test parameters include a target remaining power and a target pulse duration;

[0013] A reference voltage determination module, configured to determine a reference voltage based on the target remaining power;

[0014] An initial test current acquisition module, used to perform a constant voltage test on the battery to be tested with the reference voltage as the test voltage, and detect the current after the test time is equal to the preset test time to obtain an initial test current;

[0015] The peak current test module is used to perform a constant voltage test on the battery to be tested according to the initial test current, the preset current step length and the target pulse duration to obtain the peak current of the battery to be tested under the test parameter test.

[0016] In a third aspect, the present invention provides a testing device, the testing device comprising:

[0017] at least one processor; and

[0018] a memory communicatively connected to the at least one processor; wherein,

[0019] The memory stores a computer program that can be executed by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the battery peak current testing method described in the first aspect of the present invention.

[0020] In a fourth aspect, the present invention provides a computer-readable storage medium storing computer instructions, wherein the computer instructions are used to enable a processor to implement the battery peak current testing method described in the first aspect of the present invention when executed.

[0021] In this embodiment, a reference voltage is first determined by the target remaining power in the test parameters of the battery to be tested, and a constant voltage test is first performed on the battery to be tested with the reference voltage to obtain an initial test current, and a test current method test is performed on the battery to be tested with the initial test current, a preset current step and a target pulse duration to obtain a peak current, that is, the initial test current is first positioned by a constant voltage test using a reference voltage, so that technical personnel in this field can position the initial test current by a reference voltage close to the cut-off voltage of the battery to be tested, and the initial test current is closer to the peak current. Compared with randomly selecting a current for a test current method test, this embodiment obtains a peak current with fewer tests, shortens the test cycle, improves the test efficiency of the battery, and ultimately improves the production efficiency of the battery.

[0022] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0024] Figure 1 is a flow chart of a battery peak current testing method provided in Embodiment 1 of the present invention;

[0025] Figure 2 is a flow chart of a battery peak current testing method provided by Embodiment 2 of the present invention;

[0026] Figure 3 is a flow chart of a battery peak current testing method provided by Embodiment 3 of the present invention;

[0027] Figure 4 It is a structural schematic diagram of a battery peak current testing device provided by Embodiment 4 of the present invention;

[0028] Figure 5 It is a structural schematic diagram of the testing equipment provided in Embodiment 5 of the present invention. DETAILED DESCRIPTION

[0029] In order to enable people in the technical field to better understand the scheme of the present invention, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present invention.

[0030] Embodiment 1

[0031] Figure 1 This is a flow chart of a battery peak current testing method provided in the first embodiment of the present invention. This embodiment can be applied to testing the charging current peak value and the discharging current peak value within the target pulse duration when the battery has a target remaining power. The method can be executed by a battery peak current testing device, which can be implemented in the form of hardware and / or software, and can be configured in a testing device. Figure 1 As shown, the battery peak current test method includes:

[0032] S101 . Determine test parameters of a battery to be tested, where the test parameters include a target remaining power and a target pulse duration.

[0033] The application scenario of this embodiment is to test the charging peak current and discharging peak current of the battery in various pulse durations under different remaining power levels. The test parameters of the battery to be tested may include the target remaining power level of the battery to be tested and the target pulse duration of the test.

[0034] For the battery to be tested, the target remaining power may be more than one, for example, the target remaining power may be at least one of 20%, 30%, 50%, 70%, 90%, and the target pulse duration may be at least one of 10s, 30s, 60s.

[0035] In an example, when the test parameters are a target remaining power of 20% and a target pulse duration of 10s, it means that it is necessary to test the charging peak current and discharging peak current of the battery under test within 10s when the remaining power is 20%; when the test parameters are a target remaining power of 30% and a target pulse duration of 30s, it means that it is necessary to test the charging peak current and discharging peak current of the battery under test within 30s when the remaining power is 30%, and so on. The test parameters indicate that it is necessary to test the charging peak current and discharging peak current of the battery under test within the pulse duration at different remaining powers.

[0036] Of course, the test parameters may also include environmental parameters, such as the ambient temperature of the test environment, etc. In addition, determining the test parameters of the battery to be tested may refer to determining the test parameters of the battery to be tested at each test point. In this embodiment, the test parameters of a test point may include the remaining power and the pulse duration, and of course, the ambient temperature. The following is an example of the test parameters of multiple test points of the battery to be tested at 25° C.:

[0037]

[0038] A test parameter table can be established in advance. When the battery to be tested needs to be tested, the remaining power and pulse duration corresponding to each test point can be obtained from the above test parameter table. For example, when it is necessary to test the charging peak current and discharging peak current of the battery to be tested at each test point, the test parameters of each test point can be found from the above test parameter table.

[0039] S102: Determine a reference voltage based on a target remaining power.

[0040] The peak current may refer to: using the test current method to charge or discharge the battery under test at a constant current, so that the current when the voltage of the battery under test is greater than the cut-off voltage (charging) or less than the cut-off voltage (discharging) is the peak current. Based on this, a reference voltage may be defined, and the absolute value of the difference between the reference voltage and the cut-off voltage is within a preset value range. In one example, during the charging peak current test, the reference voltage is less than the cut-off voltage, and the preset value is 0.02-0.03, and the greater the remaining power, the smaller the reference voltage; during the discharge peak current test, the reference voltage is greater than the cut-off voltage, the preset value is 0.08-0.11, and the greater the remaining power, the greater the reference voltage.

[0041] Exemplarily, during the charging peak current test, the cut-off voltage of the battery to be tested is 3.65V, when the target remaining power is 30% to 70%, the reference voltage can be 3.60~3.63V, when the target remaining power is 90%, the reference voltage can be 3.58~3.62V; during the discharge peak current test, the cut-off voltage of the battery to be tested is 2.50V, when the target remaining power is 60%, the reference voltage can be 2.60~2.65V, when the target remaining power is 50%, the reference voltage can be 2.60~2.65V, when the target remaining power is 20%, the reference voltage is 2.58~2.63V, and the preset test duration is 15s.

[0042] Of course, those skilled in the art may also set different cut-off voltages and reference voltages according to different specified batteries, and the embodiment of the present invention does not limit the cut-off voltage and the reference voltage.

[0043] Optionally, for the battery to be tested, a remaining power-reference voltage comparison table may be pre-established for the battery to be tested, in which different remaining powers correspond to reference voltages, so as to find the reference voltage corresponding to the target remaining power in the remaining power-reference voltage comparison table.

[0044] S103, testing the battery to be tested by using the reference voltage as the test voltage, and detecting the current after the test time is equal to the preset test time to obtain an initial test current.

[0045] Specifically, the remaining power of the battery to be tested can be adjusted to the target remaining power first, and then the reference voltage is used as the test voltage to perform constant voltage charging or constant voltage discharge on the battery to be tested, and the test duration is counted when the test starts. When the test duration is equal to the preset test duration (for example, it can be 15s), the charging current or discharging current is detected, and the detected charging current or discharging current is used as the initial test current.

[0046] S104 , testing the battery to be tested according to the initial test current, the preset current step length, and the target pulse duration, and obtaining the peak current of the battery to be tested under the test parameter test.

[0047] This embodiment adopts the test current method to iteratively test the battery to be tested, so as to obtain the peak current of the battery to be tested under different test parameter tests, wherein the iterative starting test current is the initial test current, and each iteration performs constant current charging or constant current discharge test on the battery to be tested, and detects the voltage of the battery to be tested in real time. During the constant current charging and constant current discharge, it is determined whether the voltage within the target pulse duration reaches the cut-off voltage. If so, the current of the previous round of iterative test is used as the peak current. If not, the test current is updated with a preset current step as the growth value, and the battery to be tested is continuously discharged or charged at a constant current with the updated test current until the voltage reaches the cut-off voltage. Since the test is started with the initial test current as the starting current, the initial test current is the current obtained after the reference voltage is used to determine the reference voltage through the target remaining power, and the battery to be tested is tested at a constant voltage with the reference voltage, so that the initial current is closer to the peak current. Compared with the prior art of randomly selecting a current as the starting current for the test current method test, the number of tests to the peak current is small.

[0048] In this embodiment, a reference voltage is first determined by the target remaining power in the test parameters of the battery to be tested, and a constant voltage test is first performed on the battery to be tested with the reference voltage to obtain an initial test current, and a test current method test is performed on the battery to be tested with the initial test current, a preset current step and a target pulse duration to obtain a peak current, that is, the initial test current is first positioned by a constant voltage test using a reference voltage, so that technical personnel in this field can position the initial test current by a reference voltage close to the cut-off voltage of the battery to be tested, and the initial test current is closer to the peak current. Compared with randomly selecting a current for a test current method test, this embodiment obtains a peak current with fewer tests, shortens the test cycle, improves the test efficiency of the battery, and ultimately improves the production efficiency of the battery.

[0049] Embodiment 2

[0050] Figure 2 This is a flow chart of a battery peak current testing method provided in the second embodiment of the present invention. The embodiment of the present invention is optimized based on the above-mentioned first embodiment. Figure 2 As shown, the battery peak current test method includes:

[0051] S201 . Determine test parameters of the battery to be tested, where the test parameters include a target remaining power and a target pulse duration.

[0052] The application scenario of this embodiment is to test the charging peak current of the battery in various pulse durations under different remaining power levels. The test parameters of the battery to be tested may include the target remaining power level of the battery to be tested and the target pulse duration of the test.

[0053] This embodiment takes the target remaining power of 30%, 50%, 70%, and 90% and the target pulse duration of 30s as an example to test the charging peak current of the battery to be tested within 30s when the target remaining power of the battery to be tested is 30%, 50%, 70%, and 90% respectively.

[0054] Of course, the target pulse duration may also be 10s, 60s, etc., and the target remaining power may also be 40%, 80%, etc. This embodiment does not limit the values ​​of the target remaining power and the target pulse duration.

[0055] S202: In a comparison table of remaining power and reference voltage established for the battery to be tested, a voltage matching the target remaining power is searched as the reference voltage.

[0056] The remaining power-reference voltage comparison table includes reference voltages corresponding to each remaining power. For each specification of the battery to be tested, different remaining powers may correspond to different reference voltages, and different remaining powers may also correspond to the same reference voltage.

[0057] A technician in this field can set up a remaining power-reference voltage comparison table for each specification of the battery to be tested. For example, after performing charging tests on a large number of batteries to be tested, the technicians in this field can obtain the reference voltage corresponding to each remaining power through data statistical analysis, so that after the battery to be tested is charged at a constant voltage for a preset period of time with the reference voltage, the charging current is detected. When the battery to be tested is tested by the test current method with the charging current as the initial test current, the charging peak current can be obtained by testing once or twice.

[0058] The following is an example of the reference voltage corresponding to different remaining power levels, as shown in Table 1:

[0059] SOC Reference voltage / V Cut-off voltage / V 30％ 3.63 3.65 50％ 3.63 3.65 70％ 3.63 3.65 90％ 3.62 3.65

[0060] It can be seen from Table 1 above that during the charging peak current test, the reference voltage is less than the cut-off voltage, and the absolute value of the difference between the reference voltage and the cut-off voltage is between 0.02-0.03. In another example, the reference voltage is negatively correlated with the remaining power, that is, the greater the remaining power, the smaller the reference voltage. In another example, when the remaining power is within a specified range (such as 30%-70% remaining power in Table 1), it has the same reference voltage (such as 3.63V). When the remaining power is greater than the specified value (such as the remaining power is greater than 90% in Table 1), it corresponds to another reference voltage (such as 3.62V).

[0061] In another optional embodiment, in addition to setting up a remaining power-reference voltage comparison table, a remaining power-reference voltage curve can also be set to determine the reference voltage corresponding to different remaining powers through the curve, or a calculation formula with the remaining power as the independent variable and the reference voltage as the dependent variable can be set to calculate the reference voltage corresponding to different remaining powers.

[0062] After determining the target remaining power of the battery to be tested, the reference voltage that matches the target remaining power can be found in the comparison table shown in Table 1. Taking the target remaining power of 30% as an example, the reference voltage is 3.63V. By using the remaining power-reference voltage comparison table pre-set for the battery to be tested, the reference voltages corresponding to different remaining powers can be quickly found.

[0063] S203: Adjust the remaining power of the battery to be tested to the target remaining power.

[0064] For each battery to be tested, when it is necessary to test the charge level of the battery to be tested to be the target remaining charge level, the peak charging current of the battery to be tested within the target pulse duration, then the remaining current of the battery to be tested needs to be adjusted to the target remaining current. In one example, when the remaining charge of the battery to be tested is greater than the target remaining charge, the battery to be tested is discharged until the remaining charge of the battery to be tested is equal to the target remaining charge; when the remaining charge of the battery to be tested is less than the target remaining charge, the battery to be tested is charged until the remaining charge of the battery to be tested is equal to the target remaining charge.

[0065] S204, performing constant voltage charging on the battery to be tested with a reference voltage, and detecting the charging current after the charging time is equal to the preset test time, to serve as the initial test current.

[0066] Specifically, when constant voltage charging of the battery to be tested is started with a reference voltage, a timer is started to count the charging time, and the charging current is detected in real time through a current detection device. The charging current detected when the charging time is equal to the preset test time is used as the initial test current. In an example, the preset test time can be 15s, and of course it can also be other time lengths.

[0067] Since the reference voltage is close to the cut-off voltage, after the battery to be tested is subjected to constant voltage charging prediction test time with the reference voltage, the charging current is close to the charging peak current. The number of tests to obtain the charging peak current by using the charging current method as the initial test current is small.

[0068] S205: Determine the initial test current as the current charging current.

[0069] This embodiment uses the test current method to iteratively test the battery to be tested to obtain the peak current of the battery to be tested when charging for the target pulse duration at the target remaining power. The initial test current can be used as the charging current of the first iteration, that is, the current charging current.

[0070] S206: Adjust the remaining power of the battery to be tested to the target remaining power.

[0071] Since the battery to be tested is charged at a constant voltage with the reference voltage in S204, it is necessary to adjust the remaining power of the battery to be tested to the target remaining power before each current test.

[0072] S207, performing constant current charging on the battery to be tested with the current charging current, and detecting the voltage of the battery to be tested.

[0073] Specifically, in the current test method, the battery to be tested is charged with a constant current at the current charging current each time, and when the constant current charging starts, the charging time is counted by a timer, and the voltage of the battery to be tested is detected by a voltage detection device.

[0074] S208: Determine whether the voltage is greater than a preset first cut-off voltage within the target pulse duration.

[0075] The first cut-off voltage is a voltage preset in the charging peak current test. Batteries to be tested of different specifications have different first cut-off voltages. When the voltage of the battery to be tested is greater than the first cut-off voltage during the current test method test, it indicates that the charging peak current is tested. It is necessary to determine whether the voltage is greater than the first cut-off voltage within the target pulse duration during each test. If so, execute S209, if not, execute S210.

[0076] S209, determining that a charging current previous to the current charging current is a charging peak current of the battery under test within a target pulse duration when the remaining power of the battery under test is the target remaining power.

[0077] If the voltage of the battery under test is greater than the cut-off voltage within the target pulse duration during constant current charging of the battery under test with the current charging current, it can be determined that the previous charging current is the peak charging current.

[0078] S210, increasing the current charging current by using a preset current step size as an adjustment value.

[0079] If, during the constant-current charging process of the battery to be tested with the current charging current, the voltage of the battery to be tested is less than the cut-off voltage after the target pulse duration ends, it can be determined that the current charging current is not the peak charging current, and the charging current is increased, that is, the charging current is increased by a preset current step as the current charging current, and the battery to be tested is returned to S206 for a new round of constant-current charging until it is detected that the voltage of the battery to be tested is greater than the first cut-off voltage.

[0080] In order to enable those skilled in the art to more clearly understand the test method of the charging peak current in the embodiment of the present invention, the following is described with reference to examples:

[0081] Take the charging peak current of the battery under test with a 1C capacity of 154Ah at 25°C and a pulse charging time of 30s at 30%, 50%, 70%, and 90% SOC points as an example;

[0082] S1. Adjust the remaining power of the battery to be tested to 30%;

[0083] S2. Determine the reference voltage of 3.63V when the SOC is 30% by Table 1. Use this reference voltage to charge the battery under test at a constant voltage for 15s. Record the current at the end of the constant voltage charging as I0.

[0084] S3, leaving the battery to be tested for 40 seconds to eliminate polarization;

[0085] S4, discharging the battery to be tested so that the SOC of the battery to be tested is adjusted to 30%;

[0086] S5, charging the battery to be tested with a constant current of I0 for 30 seconds, and recording the voltage of the battery to be tested in real time. If the voltage does not reach the cut-off voltage of 3.65V, execute S6, otherwise execute S11;

[0087] S6. Leave the battery to be tested for 40 seconds to eliminate polarization;

[0088] S7, discharging the battery to be tested so that the SOC of the battery to be tested is adjusted to 30%;

[0089] S8, the charging current is increased by 0.2C to obtain the current I1, and the battery to be tested is charged with the current I1 at a constant current for 30s, and the voltage of the battery to be tested is recorded in real time. If the voltage does not reach the cut-off voltage of 3.65V, execute S9, otherwise execute S11;

[0090] S9, leaving the battery to be tested for 40 seconds to eliminate polarization;

[0091] S10, discharging the battery to be tested so that the SOC of the battery to be tested is adjusted to 30%, repeating the above S8-S9 until the voltage reaches the cut-off voltage of 3.65V, and then executing S11;

[0092] S11, determining the last charging current as the charging peak current;

[0093] S12, looping from S1 to S11 until the peak charging current at the pulse charging time of 30s at the SOC points of 50%, 70%, and 90% is completed.

[0094] The test results are shown in Table 2 below:

[0095]

[0096] Taking the case of 30% SOC in Table 2 as an example, the battery to be tested is first charged at constant voltage for 15s with a reference voltage of 3.63. At the end of constant voltage charging, I0 = 545A. After the SOC of the battery to be tested is adjusted to 30%, the battery to be tested is charged at constant current with I0 = 545A. At the end of constant current charging for 30s, the voltage of the battery to be tested is 3.6432V, which has not yet reached the cut-off voltage of 3.65V. Then, 0.2C is added to I0 = 545A to obtain current I1 = 576A. The battery to be tested is charged at constant current with current I1. When the charging time is 20.41s, the voltage reaches the cut-off voltage. Then the current I0 is determined as the charging peak current within 30s when the battery to be tested has a remaining capacity of 30%. Then, according to the above steps, the charging peak current of the battery to be tested is tested at 50%, 70%, and 90% SOC points when the pulse charging time is 30s.

[0097] From the test data in Table 2 above, it can be seen that after the current I0 is obtained by constant voltage charging with a reference voltage, the charging peak current is tested by the current test method using I0 as the charging current. The charging peak current can be obtained through two tests. Compared with randomly selecting a current as the charging current for the current test method test, the number of tests is greatly reduced.

[0098] After determining the target remaining capacity and target pulse duration of the battery to be tested, the present embodiment searches for a voltage matching the target remaining capacity in a remaining capacity-reference voltage comparison table established for the battery to be tested as the reference voltage, performs constant voltage charging on the battery to be tested with the reference voltage, detects the charging current after the charging duration is equal to the preset test duration, and uses it as the initial test current. The initial test current is determined as the current charging current, and the battery to be tested is charged with the current charging current at a constant current, and detects the voltage of the battery to be tested to determine whether the voltage is greater than the preset first cut-off voltage within the target pulse duration. If so, it is determined that the previous charging current of the current charging current is the charging peak current of the battery to be tested within the target pulse duration when the remaining capacity of the battery to be tested is the target remaining capacity. If not, the current charging current is increased by the preset current step as the adjustment value to continue testing the charging peak current, so that those skilled in the art can locate the initial test current by a reference voltage close to the cut-off voltage of the battery to be tested, and the initial test current is closer to the charging peak current. Compared with randomly selecting a current for the current test method test, the present embodiment obtains fewer tests for the charging peak current, shortens the test cycle, improves the battery test efficiency, and ultimately improves the battery production efficiency.

[0099] Embodiment 3

[0100] Figure 3This is a flow chart of a battery peak current testing method provided in Embodiment 3 of the present invention. This embodiment of the present invention is optimized based on Embodiment 1 above. Figure 3 As shown, the battery peak current test method includes:

[0101] S301 : Determine test parameters of the battery to be tested, where the test parameters include a target remaining power and a target pulse duration.

[0102] The application scenario of this embodiment is to test the discharge peak current of the battery in various pulse durations at different remaining capacities. The test parameters of the battery to be tested may include the target remaining capacity of the battery to be tested and the target pulse duration of the test.

[0103] This embodiment takes the target remaining power of 60%, 50%, and 20% and the target pulse duration of 60s as an example to test the discharge peak current of the battery under test within 60s when the target remaining power of the battery under test is 60%, 50%, and 20% respectively.

[0104] Of course, the target pulse duration may also be 10s, 30s, etc., and the target remaining power may also be 40%, 80%, etc. This embodiment does not limit the values ​​of the target remaining power and the target pulse duration.

[0105] S302: In a comparison table of remaining power and reference voltage established for the battery to be tested, a voltage matching the target remaining power is searched as the reference voltage.

[0106] A technician in this field can set up a remaining power-reference voltage comparison table for each specification of the battery to be tested. For example, after performing discharge tests on a large number of batteries to be tested, the technicians in this field can obtain the reference voltage corresponding to each remaining power through data statistical analysis, so that after the battery to be tested is subjected to constant voltage discharge for a preset period of time using the reference voltage, the discharge current is detected, and when the test battery is tested using the test current method with the discharge current as the initial test current, the discharge peak current can be obtained by testing once or twice.

[0107] The following is an example of the reference voltage corresponding to different remaining power levels, as shown in Table 3:

[0108] SOC Reference voltage / V Cut-off voltage / V 60％ 2.61 2.50 50％ 2.60 2.50 20％ 2.58 2.50

[0109] S303: Adjust the remaining power of the battery to be tested to the target remaining power.

[0110] Taking the discharge peak current of the battery to be tested when the remaining power is 60% as an example, the remaining power of the battery to be tested needs to be adjusted to 60%.

[0111] S304, performing constant voltage discharge on the battery to be tested with a reference voltage, and detecting a discharge current after the discharge time is equal to a preset test time to serve as an initial test current.

[0112] As shown in Table 3 above, the battery to be tested is discharged at a constant voltage of 2.61V, and the discharge current is detected after the discharge time is equal to the preset test time. The discharge current is recorded as the initial test current after discharging at a constant voltage of 2.61V for 30s.

[0113] S305: Determine the initial test current as the current discharge current.

[0114] S306: Adjust the remaining power of the battery to be tested to the target remaining power.

[0115] The remaining power of the battery to be tested is adjusted to 60%.

[0116] S307 , performing constant current discharge on the battery to be tested with the current discharge current, and detecting the voltage of the battery to be tested.

[0117] Specifically, in the current test method, the battery to be tested is discharged at a constant current with the current discharge current each time, the discharge duration is counted by a timer when the constant current discharge starts, and the voltage of the battery to be tested is detected by a voltage detection device.

[0118] S308, determining whether the voltage is less than a preset second cut-off voltage within the target pulse duration;

[0119] The second cutoff voltage is a voltage preset in the discharge peak current test. Batteries to be tested of different specifications have different second cutoff voltages. When the voltage of the battery to be tested is less than the second cutoff voltage during the current test method test, it indicates that the discharge peak current is tested. It is necessary to determine whether the voltage is less than the second cutoff voltage within the target pulse duration during each test. If so, execute S309; ​​if not, execute S310.

[0120] S309, determining that a discharge current previous to the current discharge current is a discharge peak current of the battery under test within a target pulse duration when the remaining power of the battery under test is the target remaining power.

[0121] If the voltage of the battery under test is less than the second cut-off voltage within the target pulse duration during constant current discharge of the battery under test with the current discharge current, it can be determined that the previous discharge current is the discharge peak current.

[0122] S310, increasing the current discharge current by taking the preset current step length as the adjustment value, and returning to the step of adjusting the remaining power of the battery to be tested to the target remaining power.

[0123] If, during the constant current discharge process of the battery to be tested with the current discharge current, the voltage of the battery to be tested is greater than the second cut-off voltage after the target pulse duration ends, it can be determined that the current discharge current is not the peak discharge current, and the discharge current is increased, that is, the discharge current is increased with a preset current step as the current discharge current, so as to return to S306 to perform a new round of constant current discharge on the battery to be tested, until it is detected that the voltage of the battery to be tested is less than the second cut-off voltage.

[0124] In order to enable those skilled in the art to more clearly understand the test method of the discharge peak current in the embodiment of the present invention, the following is described with reference to examples:

[0125] Take the discharge peak current of the battery with a 1C capacity of 130Ah at 10°C and a pulse discharge duration of 60s at 60%, 50%, and 20% SOC as an example:

[0126] The specific steps of Example 1 are as follows:

[0127] S1. Adjust the remaining power of the battery to be tested to 60%;

[0128] S2. Determine the reference voltage of 2.61V when the SOC is 60% by Table 3. Use this reference voltage to discharge the battery under test at a constant voltage for 30s. Record the current at the end of the constant voltage discharge as I0.

[0129] S3, leaving the battery to be tested for 40 seconds to eliminate polarization;

[0130] S4, charging the battery to be tested so that the SOC of the battery to be tested is adjusted to 30%;

[0131] S5, discharge the battery to be tested at a constant current of 10 for 60 seconds, and record the voltage of the battery to be tested in real time. If the voltage is greater than the cut-off voltage of 2.50V, execute S6, otherwise execute S11;

[0132] S6. Leave the battery to be tested for 40 seconds to eliminate polarization;

[0133] S7, charging the battery to be tested so that the SOC of the battery to be tested is adjusted to 30%;

[0134] S8, the discharge current is increased by 0.2C to obtain the current I1, and the battery to be tested is discharged at a constant current for 60s with the current I1, and the voltage of the battery to be tested is recorded in real time. If the voltage is greater than the cut-off voltage 2.50V, execute S9, otherwise execute S11;

[0135] S9, leaving the battery to be tested for 40 seconds to eliminate polarization;

[0136] S10, charging the battery to be tested so that the SOC of the battery to be tested is adjusted to 30%, repeating the above S8-9 until the voltage is less than the cut-off voltage of 2.5V, and then executing S11;

[0137] S11, determining the last discharge current as the discharge peak current;

[0138] S12, cycle S1 to S11 until the discharge peak current is reached when the pulse charging time is 60s and the SOC point is 50%, 20%.

[0139] The test results are shown in Table 4 below:

[0140]

[0141] Taking the SOC of 60% in Table 4 as an example, the battery to be tested is first discharged at a constant voltage of 2.61 for 30s. At the end of the constant voltage discharge, I0=690A. After the SOC of the battery to be tested is adjusted to 60%, the battery to be tested is discharged at a constant current of I0=690A. At the end of the constant current discharge for 60s, the voltage of the battery to be tested is 2.5130V, which has not reached the cut-off voltage of 2.5V. Then, 0.2C is added to I0=690A to obtain a current I1=716A. The battery to be tested is discharged at a constant current of I1. When the discharge time is 23s, the voltage reaches the cut-off voltage of 2.5V. Then, the current I0 is determined as the discharge peak current within 60s when the battery to be tested has a remaining capacity of 60%. Then, according to the above steps, the discharge peak current of the battery to be tested at the SOC points of 50% and 20% when the pulse charging time is 60s is tested in sequence.

[0142] From the test data in the above table, we can know that after the current I0 is obtained by constant voltage discharge through the reference voltage, the discharge peak current is tested by the current test method using I0 as the discharge current. The discharge peak current can be obtained through two tests. Compared with randomly selecting a current as the discharge current for the current test method test, the number of tests is greatly reduced.

[0143] After determining the target remaining power and target pulse duration of the battery to be tested, this embodiment searches for a voltage matching the target remaining power as the reference voltage in a remaining power-reference voltage comparison table established for the battery to be tested, performs constant voltage discharge on the battery to be tested with the reference voltage, and detects the discharge current as the initial test current after the discharge duration is equal to the preset test duration. The initial test current is determined as the current discharge current, and the battery to be tested is discharged at a constant current with the current discharge current, and the voltage of the battery to be tested is detected to determine whether the voltage is greater than the preset second cut-off voltage within the target pulse duration. If so, the front end of the current discharge current is determined. When a discharge current is the target remaining power of the battery to be tested, the peak discharge current of the battery to be tested within the target pulse duration. If not, the current discharge current is increased by taking the preset current step as the adjustment value to continue testing the discharge peak current, so that those skilled in the art can locate the initial test current by a reference voltage close to the cut-off voltage of the battery to be tested. The initial test current is closer to the discharge peak current. Compared with randomly determining a current to perform a test current method test, the present embodiment obtains a smaller number of tests for obtaining the discharge peak current, shortens the test cycle, improves the test efficiency of the battery, and ultimately improves the production efficiency of the battery.

[0144] Embodiment 4

[0145] Figure 4 This is a schematic diagram of the structure of a battery peak current test device provided by the fourth embodiment of the present invention. Figure 4 As shown, the battery peak current test device includes:

[0146] A test parameter determination module 401 is used to determine the test parameters of the battery to be tested, wherein the test parameters include a target remaining power and a target pulse duration;

[0147] A reference voltage determination module 402, configured to determine a reference voltage based on the target remaining power;

[0148] An initial test current acquisition module 403 is used to test the battery to be tested using the reference voltage as the test voltage, and detect the current after the test time is equal to the preset test time to obtain an initial test current;

[0149] The peak current testing module 404 is used to test the battery to be tested according to the initial test current, the preset current step length and the target pulse duration to obtain the peak current of the battery to be tested under the test parameter test.

[0150] Optionally, the reference voltage determination module 402 includes:

[0151] The reference voltage search unit is used to search for a voltage matching the target remaining power as the reference voltage in a remaining power-reference voltage comparison table established for the battery to be tested.

[0152] Optionally, the initial test current acquisition module 403 includes:

[0153] A first target remaining power adjustment unit, used for adjusting the remaining power of the battery to be tested to the target remaining power;

[0154] The constant voltage charging unit is used to perform constant voltage charging on the battery to be tested with the reference voltage, and detect the charging current after the charging time is equal to the preset test time, so as to serve as the initial test current.

[0155] Optionally, the peak current testing module 404 includes:

[0156] a current charging current determining unit, configured to determine the initial test current as the current charging current;

[0157] A second target remaining power adjustment unit, used for adjusting the remaining power of the battery to be tested to the target remaining power;

[0158] A constant current charging unit, used for performing constant current charging on the battery to be tested with the current charging current, and detecting the voltage of the battery to be tested;

[0159] A charging cut-off voltage judgment unit, used to judge whether the voltage is greater than a preset first cut-off voltage within the target pulse duration;

[0160] a charging peak current determining unit, configured to determine that a charging current previous to the current charging current is a charging peak current of the battery under test within the target pulse duration when the remaining power of the battery under test is the target remaining power;

[0161] The current charging current adjustment unit is used to increase the current charging current by a preset current step length as an adjustment value, and return to the second target remaining power adjustment unit.

[0162] Optionally, the initial test current acquisition module 403 includes:

[0163] a third target remaining power adjustment unit, configured to adjust the remaining power of the battery to be tested to the target remaining power;

[0164] The constant voltage discharge unit is used to perform constant voltage discharge on the battery to be tested with the reference voltage, and detect the discharge current as the initial test current after the discharge time is equal to the preset test time.

[0165] Optionally, the peak current testing module 404 includes:

[0166] a current discharge current determination unit, configured to determine the initial test current as the current discharge current;

[0167] a fourth target remaining power adjustment unit, configured to adjust the remaining power of the battery to be tested to the target remaining power;

[0168] A constant current discharge unit, used for performing constant current discharge on the battery to be tested with the current discharge current, and detecting the voltage of the battery to be tested;

[0169] A discharge cut-off voltage judgment unit, used to judge whether the voltage is less than a preset second cut-off voltage within the target pulse duration;

[0170] a discharge peak current determination unit, configured to determine that a discharge current previous to the current discharge current is a discharge peak current of the battery under test within the target pulse duration when the remaining power of the battery under test is the target remaining power;

[0171] The current discharge current adjustment unit is used to increase the current discharge current by taking a preset current step length as an adjustment value, and return to the fourth target remaining power adjustment unit.

[0172] Optionally, during the charging peak current test, the cut-off voltage of the battery to be tested is 3.65V, when the target remaining power is 30% to 70%, the reference voltage is 3.60 to 3.63V, and when the target remaining power is 90%, the reference voltage is 3.58 to 3.62V;

[0173] During the discharge peak current test, the cut-off voltage of the battery to be tested is 2.50V, when the target remaining power is 60%, the reference voltage is 2.60-2.65V, when the target remaining power is 50%, the reference voltage is 2.60-2.65V, when the target remaining power is 20%, the reference voltage is 2.58-2.63V;

[0174] The preset test duration is 15 seconds.

[0175] The battery peak current testing device provided in the embodiment of the present invention can execute the battery peak current testing method provided in the first, second and third embodiments of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0176] Embodiment 5

[0177] Figure 5 A schematic diagram of a test device 50 that can be used to implement an embodiment of the present invention is shown. Test device 50 is intended to represent a device that includes various forms of digital computers, such as a laptop computer, desktop computer, workstation, personal digital assistant, server, blade server, mainframe computer, and other suitable computers.

[0178] like Figure 5 As shown, the test device 50 includes at least one processor 51, and a memory connected to the at least one processor 51, such as a read-only memory (ROM) 52, a random access memory (RAM) 53, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 51 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 52 or the computer program loaded from the storage unit 58 to the random access memory (RAM) 53. In the RAM 53, various programs and data required for the operation of the test device 50 can also be stored. The processor 51, the ROM 52 and the RAM 53 are connected to each other through a bus 54. An input / output (I / O) interface 55 is also connected to the bus 54.

[0179] A number of components in the test device 50 are connected to the I / O interface 55, including: an input unit 56, such as a keyboard, a mouse, etc.; an output unit 57, such as various types of displays, speakers, etc.; a storage unit 58, such as a disk, an optical disk, etc.; and a communication unit 59, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 59 allows the test device 50 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0180] The processor 51 may be a variety of general and / or dedicated processing components with processing and computing capabilities. Some examples of the processor 51 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 51 executes the various methods and processes described above, such as a battery peak current test method.

[0181] In some embodiments, the battery peak current test method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 58. In some embodiments, part or all of the computer program may be loaded and / or installed on the test device 50 via the ROM 52 and / or the communication unit 59. When the computer program is loaded into the RAM 53 and executed by the processor 51, one or more steps of the battery peak current test method described above may be performed. Alternatively, in other embodiments, the processor 51 may be configured to execute the battery peak current test method in any other appropriate manner (e.g., by means of firmware).

[0182] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0183] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0184] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0185] To provide interaction with a user, the systems and techniques described herein may be implemented on a test device 50 having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the test device 50. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0186] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0187] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A battery peak current testing method, characterized in that: include: Determine test parameters of the battery to be tested, wherein the test parameters include a target remaining power and a target pulse duration; The reference voltage is determined based on the target remaining power; wherein the absolute value of the difference between the reference voltage and the cut-off voltage is within a preset value range; during the charging peak current test, the reference voltage is less than the cut-off voltage, and the greater the remaining power, the smaller the reference voltage; during the discharging peak current test, the reference voltage is greater than the cut-off voltage, and the greater the remaining power, the greater the reference voltage; Testing the battery to be tested using the reference voltage as the test voltage, and detecting the current after the test time is equal to the preset test time to obtain an initial test current; The battery to be tested is tested according to the initial test current, the preset current step length, and the target pulse duration to obtain a peak current of the battery to be tested under the test parameter test.

2. The battery peak current testing method according to claim 1, characterized in that: The determining of the reference voltage based on the target remaining power comprises: In the remaining power-reference voltage comparison table established for the battery to be tested, a voltage matching the target remaining power is searched as the reference voltage.

3. The battery peak current testing method according to claim 1, characterized in that: The method of testing the battery to be tested by using the reference voltage as the test voltage and detecting the current after the test time is equal to the preset test time to obtain the initial test current includes: Adjusting the remaining power of the battery to be tested to the target remaining power; The battery to be tested is charged at a constant voltage using the reference voltage, and a charging current is detected after the charging time is equal to the preset test time to serve as an initial test current.

4. The battery peak current testing method according to claim 3, characterized in that: The step of testing the battery to be tested according to the initial test current, the preset current step length, and the target pulse duration to obtain a peak current of the battery to be tested under the test parameter test includes: Determining the initial test current as the current charging current; Adjusting the remaining power of the battery to be tested to the target remaining power; Performing constant current charging on the battery to be tested with the current charging current, and detecting the voltage of the battery to be tested; Determining whether the voltage is greater than a preset first cut-off voltage within the target pulse duration; If yes, determining that the charging current before the current charging current is the charging peak current of the battery under test within the target pulse duration when the remaining power of the battery under test is the target remaining power; If not, the current charging current is increased by using a preset current step length as an adjustment value, and the process returns to the step of adjusting the remaining power of the battery to be tested to the target remaining power.

5. The battery peak current testing method according to claim 1, characterized in that: The method of testing the battery to be tested by using the reference voltage as the test voltage and detecting the current after the test time is equal to the preset test time to obtain the initial test current includes: Adjusting the remaining power of the battery to be tested to the target remaining power; The battery to be tested is discharged at a constant voltage using the reference voltage, and a discharge current is detected after the discharge duration is equal to the preset test duration to serve as an initial test current.

6. The battery peak current testing method according to claim 5, characterized in that: The step of testing the battery to be tested according to the initial test current, the preset current step length, and the target pulse duration to obtain a peak current of the battery to be tested under the test parameter test includes: Determining the initial test current as the current discharge current; Adjusting the remaining power of the battery to be tested to the target remaining power; Performing constant current discharge on the battery to be tested with the current discharge current, and detecting the voltage of the battery to be tested; Determining whether the voltage is less than a preset second cut-off voltage within the target pulse duration; If yes, determining that the previous discharge current of the current discharge current is the discharge peak current of the battery under test within the target pulse duration when the remaining power of the battery under test is the target remaining power; If not, the current discharge current is increased by using a preset current step length as an adjustment value, and the process returns to the step of adjusting the remaining power of the battery to be tested to the target remaining power.

7. The battery peak current testing method according to any one of claims 1 to 6, characterized in that: During the charging peak current test, the cut-off voltage of the battery to be tested is 3.65V, when the target remaining power is 30% to 70%, the reference voltage is 3.60~3.63V, and when the target remaining power is 90%, the reference voltage is 3.58~3.62V; During the discharge peak current test, the cut-off voltage of the battery to be tested is 2.50V, when the target remaining power is 60%, the reference voltage is 2.60~2.65V, when the target remaining power is 50%, the reference voltage is 2.60~2.65V, when the target remaining power is 20%, the reference voltage is 2.58~2.63V; The preset test duration is 15 seconds.

8. A battery peak current test device, characterized in that: include: A test parameter determination module, used to determine the test parameters of the battery to be tested, wherein the test parameters include a target remaining power and a target pulse duration; A reference voltage determination module, configured to determine a reference voltage based on the target remaining power; wherein the absolute value of the difference between the reference voltage and the cut-off voltage is within a preset value range; during a charging peak current test, the reference voltage is less than the cut-off voltage, and the greater the remaining power, the smaller the reference voltage; during a discharging peak current test, the reference voltage is greater than the cut-off voltage, and the greater the remaining power, the greater the reference voltage; An initial test current acquisition module, used to test the battery to be tested with the reference voltage as the test voltage, and detect the current after the test time is equal to the preset test time to obtain an initial test current; The peak current testing module is used to test the battery to be tested according to the initial test current, the preset current step length and the target pulse duration to obtain the peak current of the battery to be tested under the test parameter test.

9. A testing device, characterized in that: The test equipment includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can perform the battery peak current testing method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the battery peak current testing method according to any one of claims 1 to 7 when executed.

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