Battery electrochemical damage consistency test method, device, equipment and medium

Abstract

The present invention discloses a battery electrochemical damage consistency test method, device, equipment and medium, the method comprising: obtaining test parameters, the test parameters are used to make each battery cell in the battery group to be tested perform a charge and discharge cycle according to the test parameters; obtaining the corresponding residual capacity of each battery cell after the charge and discharge cycle; according to the initial capacity and residual capacity of each battery cell, determining the damage deviation between two battery cells in a control group in a conventional battery group and a fast-charge battery group. The present invention determines the difference in the degree of electrochemical damage of each battery cell under the same fast-charge test conditions, that is, the damage deviation, by comparing the damage degree of each fast-charge cell horizontally, to characterize the consistency of the electrochemical damage test taken. The consistency performance is good, providing a feasible test method for testing electrochemical damage in the actual production and use of the battery.

Description

Technical Field

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

[0002] As a widely used energy storage device in modern society, batteries play an important role in the fields of automobiles, mobile phones, electronic products, etc. However, during the use of batteries, damage caused by various reasons, such as electrochemical damage, makes the batteries have safety hazards, which may lead to battery performance degradation or even explosion and fire.

[0003] There are few testing schemes for battery damage in the existing technology. It is crucial to measure the battery damage through reasonable testing methods and further measure the related performance changes of the damaged battery in order to understand the safety and reliability of the battery during use. However, the testing experiments are accidental, which makes it impossible to test the battery cells used in battery systems in batches one by one.

[0004] Therefore, damage consistency in battery safety performance testing has become one of the issues that the battery industry urgently needs to address. Summary of the invention

[0005] The purpose of the present invention is to provide a battery electrochemical damage consistency test method, device, equipment and medium, so as to provide a reliable test method for battery electrochemical damage consistency test.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] In a first aspect, the present invention provides a battery electrochemical damage consistency testing method, the method comprising:

[0008] Acquire test parameters, where the test parameters are used to make each battery cell in the battery group to be tested perform a charge and discharge cycle according to the test parameters, where the battery group to be tested includes a conventional battery group and a fast-charge battery group, where the conventional battery group includes at least one conventional battery cell, and the fast-charge battery group includes at least one fast-charge battery cell, where the conventional battery cells and the fast-charge batteries correspond one to one to form at least one control group, and where the test parameters include the charging efficiency and the discharging efficiency of each battery cell in the battery group to be tested, where the charging efficiency of the conventional battery cell is less than the charging efficiency of the fast-charge battery cell;

[0009] Obtain the remaining capacity of each battery cell after the charge and discharge cycle is performed;

[0010] Based on the initial capacity of each battery cell and the remaining capacity, the damage deviation between the two battery cells in the control group in the conventional battery pack and the fast-charging battery pack is determined, and the damage deviation indicates the consistency of the corresponding electrochemical damage test when the battery pack to be tested performs a charge and discharge cycle based on the test parameters.

[0011] Optionally, in the battery electrochemical damage consistency testing method provided by the present invention, the test parameters also include a charging cut-off voltage, a discharging cut-off voltage and a cycle period, and the charging efficiency for the conventional battery pack is lower than the charging efficiency for the fast-charging battery pack.

[0012] Optionally, the battery electrochemical damage consistency testing method provided by the present invention further comprises:

[0013] Based on the damage deviation, a consistency result of an electrochemical damage test corresponding to the battery pack to be tested when the battery pack to be tested performs a charge and discharge cycle based on the test parameters is determined.

[0014] Optionally, in the battery electrochemical damage consistency testing method provided by the present invention, determining the damage deviation between two battery cells in a control group in the conventional battery pack and the fast-charge battery pack according to the initial capacity and the remaining capacity of each battery cell comprises:

[0015] Determining a capacity retention rate of each battery cell according to the initial capacity and the remaining capacity;

[0016] Determining the battery damage of the fast-charging cells in each control group according to the capacity retention rate of each cell;

[0017] The damage deviation of each control group is determined according to the damage of each fast charging cell.

[0018] Optionally, in the battery electrochemical damage consistency testing method provided by the present invention, determining the capacity retention rate of each battery cell according to the initial capacity and the remaining capacity comprises:

[0019] The percentage of the remaining capacity of each battery cell to the initial capacity is calculated, and the percentage is used as the capacity retention rate of each battery cell.

[0020] Optionally, in the battery electrochemical damage consistency testing method provided by the present invention, determining the battery damage of the fast-charging cells in each control group according to the capacity retention rate of each battery cell comprises:

[0021] The difference between the capacity retention rate of the fast-charged cell in each control group and the capacity retention rate of the conventional cell was calculated as the damage of the fast-charged cell in each control group.

[0022] Optionally, in the battery electrochemical damage consistency testing method provided by the present invention, the determining the damage deviation of each control group according to the damage of each fast charging cell comprises:

[0023] Calculate the mean value of the damage deviation of each fast charging cell in each control group;

[0024] The difference between the damage of the fast-charging cells in each control group and the mean is calculated as the damage deviation of each fast-charging cell.

[0025] In a second aspect, the present invention provides a battery electrochemical damage consistency testing device, the device comprising:

[0026] A test module, used to obtain test parameters, wherein the test parameters are used to make each battery cell in the battery group to be tested perform a charge and discharge cycle according to the test parameters, wherein the battery group to be tested includes a conventional battery group and a fast-charge battery group, wherein the conventional battery group includes at least one conventional battery cell, and the fast-charge battery group includes at least one fast-charge battery cell, wherein the conventional battery cells and the fast-charge batteries correspond one to one to form at least one control group, wherein the test parameters include the charging efficiency and the discharging efficiency of each battery cell in the battery group to be tested, wherein the charging efficiency of the conventional battery cell is less than the charging efficiency of the fast-charge battery cell;

[0027] An acquisition module is used to obtain the remaining capacity of each battery cell after performing a charge and discharge cycle;

[0028] A determination module is used to determine the damage deviation between two battery cells in the control group in the conventional battery pack and the fast-charging battery pack based on the initial capacity of each battery cell and the remaining capacity, wherein the damage deviation indicates the consistency of the corresponding electrochemical damage test when the battery pack to be tested performs a charge and discharge cycle based on the test parameters.

[0029] In a third aspect, the present invention provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the battery electrochemical damage consistency testing method as described in the first aspect.

[0030] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the battery electrochemical damage consistency testing method as described in the first aspect is implemented.

[0031] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0032] The present invention provides a battery electrochemical damage consistency test method, device, equipment and medium, which performs multiple charge and discharge cycle operations on each battery cell in a battery pack to be tested according to set test parameters, that is, the battery cells in a conventional battery pack are charged and discharged according to conventional efficiency, and the battery cells in a fast-charging battery pack are charged and discharged quickly with high efficiency, and then the battery capacity after multiple charge and discharge cycles is tested, so as to utilize the capacity changes of each battery cell in the conventional battery pack and the fast-charging battery pack to determine the electrochemical damage degree of the battery cell after multiple charge and discharge cycles, and finally compare the damage degree of each fast-charging cell horizontally to determine the difference in the electrochemical damage degree of each battery cell under the same fast-charging test conditions, that is, the damage deviation, to characterize the consistency of the electrochemical damage test taken.

[0033] That is, the battery electrochemical damage testing method provided by the present invention has good consistency performance, and provides a feasible testing method for testing electrochemical damage during the actual production and use of the battery, that is, the effectiveness of the testing method is determined to ensure that during the battery development process, the battery developed using the testing method meets the relevant performance requirements, that is, the accuracy is higher, and a feasible testing idea is provided for the design and development of safe battery systems and methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 A schematic diagram of the structure of a battery electrochemical damage consistency test system according to some embodiments of the present invention;

[0036] Figure 2 A schematic diagram of a flow chart of a battery electrochemical damage consistency testing method according to some embodiments of the present invention;

[0037] Figure 3 Schematic diagram of the flow chart of the battery electrochemical damage consistency testing method according to some other embodiments of the present invention;

[0038] Figure 4 A schematic diagram of battery electrochemical damage consistency test results according to some embodiments of the present invention;

[0039] Figure 5 A schematic diagram of battery electrochemical damage consistency test results according to some other embodiments of the present invention;

[0040] Figure 6A schematic diagram of the structure of a battery electrochemical damage consistency testing device according to some embodiments of the present invention;

[0041] Figure 7 A schematic diagram of the structure of a computer device provided for some embodiments of the present invention. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments 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 this field without creative work are within the scope of protection of the present invention.

[0043] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] It is understandable that various factors can cause damage to batteries during production and use. For example, mechanical damage, fast charging damage, production damage, etc. can all cause changes in their performance and may also cause fires and explosions.

[0045] It can be understood that the battery is a battery cell structure with charging and discharging functions suitable for new energy vehicles or electric bicycles, electric motorcycles or other scenarios.

[0046] For example, when the battery is fast charged, the large current causes concentration polarization of the electrode, causing the potential difference between the positive and negative electrodes to deviate from the equilibrium potential. When the current is very high, the semipermeable membrane on the surface of the negative electrode will begin to rupture, and the electrode material and the electrolyte will react. The electrode material is destroyed, which will cause the battery capacity to decay. In addition, high current charging will increase the internal resistance, thereby generating heat or other side reactions, such as reaction decomposition and gas production of the electrolyte.

[0047] That is, during the fast charging process of the battery, the above-mentioned series of chemical reactions will be caused, which is called electrochemical damage to the battery.

[0048] It can also be understood that, in practice, fast charging of a battery usually refers to the damage to the battery caused by a charging efficiency of 3C or 4C.

[0049] In the present invention, in order to accurately test the damage caused to the battery cells by fast charging, that is, to clarify the accurate consistency test method for the electrochemical damage caused to the battery during the fast charging of the battery cells, based on the constructed experimental platform, by charging and discharging the battery samples for multiple cycles and synchronously testing the electrical parameters of the battery, an effective and feasible consistency test method for the electrochemical damage of the battery is obtained, which provides a feasible test method for the test of electrochemical damage in the actual production and use of the battery, that is, the effectiveness of the test method is determined to ensure that in the battery development process, the battery developed using the test method meets the relevant performance requirements, that is, the accuracy is higher, which provides a feasible testing idea for the design and development of safe battery systems and methods.

[0050] like Figure 1 FIG. 1 is a schematic diagram of the framework structure of a battery electrochemical damage consistency test system implemented in the present invention.

[0051] The system may include a host computer, a charging and discharging device, and a test box. The battery cell to be tested is placed in the test box, and the test box is provided with a sensor and a test circuit electrically connected to the host computer to transmit the monitoring parameters of the battery cell after multiple charging and discharging to the host computer for analysis by the host computer.

[0052] Among them, a cable bridge is configured between the host computer, the test box and the charging and discharging equipment to achieve electrical connection between the host computer, the charging and discharging equipment and the battery to be tested.

[0053] For example, the host computer, charging and discharging equipment, and test box can be placed in different rooms, and communicate and connect with each other through power lines, network cables, and RS-485.

[0054] In practice, a control program for testing may be installed on the host computer, so that the operator can send test instructions and parameters to the charging and discharging equipment and the battery cells to be tested, and obtain monitoring parameters returned by the test box by running the control program, i.e., through the control program on the host computer.

[0055] In addition, the host computer may also run a parameter analysis program to effectively analyze the received performance parameters and obtain consistency results during the test process. For example, a test method such as HPPC may be run to analyze the monitoring parameters.

[0056] In order to better understand the battery electrochemical damage consistency testing method provided by the present invention, it is described in detail below through a flow chart.

[0057] Figure 2 FIG. 1 is a flow chart of a method for testing the consistency of battery electrochemical damage according to some embodiments of the present invention. Figure 2 shown.

[0058] This method can be done by Figure 1The method is performed by the host computer shown in the figure, and specifically includes:

[0059] S110, obtaining test parameters, where the test parameters are used to make each battery cell in the battery group to be tested perform a charge and discharge cycle according to the test parameters, where the battery group to be tested includes a conventional battery group and a fast-charge battery group, where the conventional battery group includes at least one conventional battery cell, and the fast-charge battery group includes at least one fast-charge battery cell, where the conventional battery cells and the fast-charge batteries correspond one to one to form at least one control group, and where the test parameters include the charging efficiency and the discharging efficiency of each battery cell in the battery group to be tested, where the charging efficiency of the conventional battery cell is less than the charging efficiency of the fast-charge battery cell.

[0060] S120, obtaining the remaining capacity of each battery cell after the charge and discharge cycle is performed.

[0061] S130, determining the damage deviation between two battery cells in the control group in the conventional battery pack and the fast-charging battery pack based on the initial capacity and the remaining capacity of each battery cell, wherein the damage deviation indicates the consistency of the corresponding electrochemical damage test when the battery pack to be tested performs a charge and discharge cycle based on the test parameters.

[0062] Specifically, in order to determine the consistency of battery electrochemical test results, in an embodiment of the present invention, a battery group to be tested can be first determined. For example, 6 to 10 battery cells produced in the same batch can be used as the battery group to be tested to perform a consistency test on electrochemical damage.

[0063] Among them, the battery group to be tested may include a conventional battery group and a fast-charging battery group, the conventional battery group includes at least one conventional battery cell to be tested, and the fast-charging battery group includes at least one fast-charging battery cell to be tested, and the battery cells in the conventional battery group and the fast-charging battery group correspond one to one to form at least one control group.

[0064] For example, for a battery pack to be tested that includes 6 cells, cells 1 to 3 can be used as regular battery packs, and cells 4 to 6 can be used as fast-charge battery packs. In addition, cells 1 and 4 correspond to each other, cells 2 and 5 correspond to each other, and cells 3 and 6 correspond to each other, so as to form three control groups.

[0065] Furthermore, test parameters are obtained so that each battery cell can perform multiple fast charging and discharging cycle operations according to the test electrical parameters, that is, the conventional battery pack and the fast charging battery pack can perform multiple charge and discharge cycles, and then the corresponding remaining capacity of each battery cell in the conventional battery pack and the fast charging battery pack after executing the charge and discharge cycle can be determined.

[0066] For example, a tester may input test parameters on an operation interface of a test program running on a host computer, so that the host computer acquires the test parameters.

[0067] The test parameter represents the charge and discharge efficiency of each battery cell in the battery pack to be tested, and the charging efficiency of the conventional battery cell is lower than the charging efficiency of the fast-charged battery cell.

[0068] In practice, the test parameters may specifically include charging efficiency, discharging efficiency, charging cut-off voltage, discharging cut-off voltage and cycle period. The charging efficiency for the conventional battery pack is lower than the charging efficiency for the fast-charging battery pack.

[0069] It can be understood that the above test parameters are the experimental conditions during the test:

[0070] As shown in Table 1 and Table 2, the test parameters correspond to the charging efficiency, discharging efficiency, charging cut-off voltage (such as constant current charging to 4.35V), discharging cut-off voltage (constant current discharging to 2.8V) and cycle period (tested every 200 cycles).

[0071] For example, combined with Figure 1 As shown, the host computer can control the charging and discharging equipment according to the acquired test parameters to charge and discharge each battery cell to be tested, that is, each battery cell to be tested performs a charging and discharging cycle according to the charging and discharging parameters.

[0072] Among them, in order to determine the consistency of the test method, the charging efficiency of the conventional battery pack is lower than that of the fast-charging battery pack, that is, the conventional battery pack is used as a sample under normal usage scenarios, and is subjected to conventional charging and discharge cycles; the fast-charging battery pack is used as a sample under fast-charging mode, and is subjected to efficient fast charging, so that consistency testing of electrochemical damage can be performed under different charging modes.

[0073] Finally, the damage deviation between the two cells in the control group of the conventional battery pack and the fast-charge battery pack can be determined based on the determined initial capacity and the remaining capacity.

[0074] The damage deviation can be used to indicate the consistency of electrochemical damage of the battery.

[0075] For example, the initial capacity and remaining capacity of the six cells can be used to calculate the damage deviations of the three control groups, namely, No. 1 and No. 4, No. 2 and No. 5, and No. 3 and No. 6, to indicate the differences in the test results of electrochemical damage under different experimental conditions.

[0076] It can be understood that the electrochemical damage consistency test method provided by the present invention performs multiple charge and discharge cycle operations on each battery cell in the tested battery pack according to the set test parameters, that is, the battery cells in the conventional battery pack are charged and discharged according to the conventional efficiency, and the battery cells in the fast-charging battery pack are charged and discharged quickly with high efficiency, and then the battery capacity after multiple charge and discharge cycles is tested, so as to utilize the capacity change of each battery cell in the conventional battery pack and the fast-charging battery pack to determine the degree of electrochemical damage of the battery cells after multiple charge and discharge cycles, and finally, the damage degree of each fast-charging cell is compared horizontally to determine the difference in the degree of electrochemical damage of each battery cell under the same fast-charging test conditions, that is, the damage deviation, to characterize the consistency of the electrochemical damage test taken.

[0077] Among them, the consistency performance is good, which provides a feasible test method for testing electrochemical damage during the actual production and use of the battery. That is, it determines the effectiveness of the test method to ensure that during the battery development process, the battery developed using this test method meets the relevant performance requirements, that is, the accuracy is higher, and provides a feasible test idea for the design and development of safe battery systems and methods.

[0078] Optionally, in some embodiments of the present invention, in order to further determine the consistency of the test results of the test method, after determining the damage deviation of each control group, the method further includes:

[0079] S140, based on the damage deviation, determining a consistency result of an electrochemical damage test corresponding to when the battery pack to be tested performs a charge and discharge cycle based on the test parameters.

[0080] Specifically, after the damage deviations of each control group are determined, each damage deviation can be fused to obtain a corresponding damage consistency result.

[0081] For example, the damage deviations of the three control groups mentioned above can be fused, that is, the difference between unit 1 and each damage deviation can be calculated, and the result with the largest value is determined to be the consistency of each battery cell of the battery group to be tested under the experimental conditions.

[0082] It can be understood that through this step, the consistency results of the damage of each battery cell during the experiment can be further accurately calculated to indicate the feasibility of the test method.

[0083] Optionally, in some embodiments of the present invention, before performing multiple charge-discharge cycle tests on each battery cell according to the test parameters, the method further includes obtaining the initial capacity of each battery cell, that is, the method may include the following steps:

[0084] S01, obtaining initial parameters, where the initial parameters are used to enable each cell in the battery pack to be tested to perform charging and discharging according to the initial parameters.

[0085] S02: Determine the initial capacity of each battery cell based on the charge and discharge results.

[0086] Specifically, in some embodiments of the present invention, when the test method is executed, initial parameters may be configured on the host computer first, and the initial parameters may be corresponding charging and discharging parameters when each battery cell is pre-processed.

[0087] For example, for each cell in the battery pack to be tested, its initial capacity is tested, that is, when the capacity is calibrated using the initial parameters, the capacity calibration can be specifically based on 0.1C:

[0088] 0.5C constant current charging, 4.35V constant voltage charging to 0.05C, 0.1C constant current discharging.

[0089] And, correspondingly, the internal resistance of the battery cell can also be calibrated:

[0090] 0.3C constant current charging to 4.35V, 4.35V constant voltage charging to 0.05C, 0.3C constant current discharging to 50% SoC, pulse charging and pulse discharging tests.

[0091] Pulse charging: 200A constant current charging for 10s;

[0092] Pulse discharge: 200A constant current charging for 10s.

[0093] Specifically, the initialization parameters of each battery cell in the battery pack to be tested can be determined by using a hybrid power pulse characteristic (HPPC) test, that is, by setting the initial charge and discharge parameters, the performance parameters such as the DC internal resistance, open circuit voltage, available power and available capacity of each battery cell can be analyzed and calculated.

[0094] It can be understood that, through the above method, the capacity and internal resistance of each battery cell in the battery pack to be tested can be calibrated, that is, the initial capacity can be determined.

[0095] The details are shown in Table 1 and Table 2:

[0096] Table 1

[0097]

[0098] Table 2

[0099]

[0100] Optionally, in some embodiments of the present invention, in S110, test parameters are obtained so that when the conventional battery cell and the fast charging cell perform charge and discharge cycles according to the test parameters, the input test parameters may specifically include corresponding parameters in the experimental conditions, namely, charging efficiency, discharging efficiency and cycle period.

[0101] For example, as shown in Table 1, for a conventional battery pack, the experimental conditions are set as follows:

[0102] 1C / C continuous constant current cycle charging, and 0.1C capacity characterization and HPPC test every 200 cycles:

[0103] Charging: 1C constant current charging to 4.35V, 4.35V constant voltage charging value 0.05C;

[0104] Discharge: 1C constant current discharge to 2.8V.

[0105] That is, for the cells in a conventional battery pack, the input test parameters may include 1C / 1C charging efficiency and discharging efficiency, as well as 200 cycles of 0.1C capacity characterization and HPPC testing.

[0106] It can be seen from Table 1 that through multiple cycles, the remaining capacity of each cell in the conventional battery pack was measured after 400 cycles and 600 cycles.

[0107] Further, in combination with Table 2, for the fast-charging battery pack, the experimental conditions are set as follows:

[0108] 2C / C continuous cycle, 0.1C capacity characterization and HPPC test every 200 cycles:

[0109] Charging: 2C constant current charging to 4.35V;

[0110] Discharge: 1C constant current discharge to 2.8V.

[0111] It can be seen from Table 2 that through multiple cycles, the remaining capacity of each cell in the fast-charging battery pack was measured after 400 cycles and 600 cycles.

[0112] It can be understood that the above-mentioned experimental conditions are merely exemplary and can be flexibly adjusted according to actual conditions. For example, when performing consistency testing under fast charging conditions, the charging efficiency of the fast charging battery pack can be 3C or 4C, that is, the present invention does not limit the experimental conditions.

[0113] Correspondingly, after the host computer controls each battery cell in the battery pack to be tested to perform multiple charge and discharge cycles, various performance parameters of the battery cell at this time can be tested.

[0114] For example, the HPPC test method can be used to determine the remaining capacity of each battery cell based on the test results received by the host computer.

[0115] Optionally, in some embodiments of the present invention, in S130, the damage deviation of the control group is determined by using the determined initial capacity and residual capacity, such as Figure 3As shown, the following steps can be taken:

[0116] S131, determining the capacity retention rate of each battery cell according to the initial capacity and the remaining capacity.

[0117] S132, determining the battery damage of the fast charging cells in each control group according to the capacity retention rate of each battery cell.

[0118] S133, determining the damage deviation of each control group according to the battery damage of each fast charging cell.

[0119] Specifically, in some embodiments of the present invention, when determining the damage deviation of each control group, the capacity retention rate of each battery cell can be calculated based on the initial capacity and the remaining capacity of each battery cell.

[0120] That is, the remaining capacity of each battery cell is divided by the initial capacity, and the quotient is used as the capacity retention rate corresponding to each battery cell.

[0121] Furthermore, the difference between the capacity retention rate of the conventional battery cell and the capacity retention rate of the fast-charged battery cell in each control group was calculated as the damage value of the fast-charged battery cell in each control group.

[0122] Finally, after calculating the damage value of the fast-charging cells in each control group, the average battery damage value of the fast-charging cells in all control groups can be calculated, and then the corresponding damage deviation can be determined using the respective battery damage values ​​and the average value.

[0123] It can be understood that through the above steps, the battery cells produced in the same batch are used as the samples to be tested, the conventional battery cells are subjected to conventional charge and discharge cycles, and the fast charge battery cells are subjected to fast charge and discharge cycles, and then the two battery cells are used as control groups to determine the corresponding damage deviations, so as to indicate the differences in the damage deviations of the multiple control groups tested under this test method, that is, the consistency of the test method is reflected through the damage deviation, so as to prove the effectiveness and feasibility of the test method.

[0124] Optionally, in some embodiments of the present invention, in S131, when determining the capacity retention rate of each battery cell, the percentage of the remaining capacity of each battery cell to the initial capacity may be calculated first, and the percentage may be used as the capacity retention rate.

[0125] Specifically, after the battery parameters after multiple charge and discharge cycles are tested through the test box and the remaining capacity of each battery cell is determined, the remaining capacity of each battery cell and the percentage of the initial capacity can be calculated as the capacity retention rate of each battery cell.

[0126] For example, as shown in Table 1, by setting the test conditions, the cells in the conventional battery pack are charged and discharged for multiple cycles, and the remaining capacity after the charge and discharge operation can be tested. Then, the percentage of the remaining capacity of each cell to the initial capacity can be calculated, and the result is used as the corresponding capacity retention rate.

[0127] For example, for battery cell No. 1, its capacity retention rate = 114.159 / 118.114*100 = 96.65%.

[0128] Similarly, the capacity retention rates of cells 2 to 5 can be calculated in sequence.

[0129] Further, in S132, when determining the battery damage of the fast charging cells in each control group based on the capacity retention rate of each battery cell, the difference between the capacity retention rate of the fast charging cells in each control group and the capacity retention rate of the conventional battery cells can be calculated as the battery damage of the fast charging cells in each control group.

[0130] For example, as shown in Table 1, for the control group of No. 1 and No. 4, the damage S of No. 4 fast charging cell can be calculated as follows:

[0131] S = capacity retention rate of cell 1 - capacity retention rate of cell 4 = 92.46% - 96.65% = -4.17%

[0132] Furthermore, through the above method, it can be calculated in sequence that in the control group of No. 2 battery cell and No. 5 battery cell, the damage of No. 5 fast charging cell is -3.15%; in the control group of No. 3 battery cell and No. 6 battery cell, the damage of No. 6 fast charging cell is -2.94%.

[0133] Optionally, in some embodiments of the present invention, after the damage of each fast charging cell in each control group is determined, the damage deviation of each control group can be determined according to the damage of the fast charging cell, which can be specifically achieved by the following steps:

[0134] S03, calculating the mean value of the battery damage deviation of the fast charging cells in each control group.

[0135] S04, calculating the difference between the battery damage of the fast charging cells in each control group and the mean value, which is the damage deviation of the fast charging cells.

[0136] Specifically, the damage of each fast charging cell can be summed up first, and then the mean value of each fast charging cell can be calculated. Further, the difference between the damage of the fast charging cell in each control group and the mean value can be used as the damage deviation of the fast charging cell.

[0137] For example, as shown in the example above, after calculating that the damage of the No. 4 fast charging cell is -4.17%, the damage of the No. 5 fast charging cell is -3.15%, and the damage of the No. 6 fast charging cell is -2.94%, the above damages are summed up to get -10.26%, and then the average is calculated, that is, -10.26% / 3=-3.42%.

[0138] Furthermore, by calculating the difference between the mean and the battery damage corresponding to each battery cell, it can be obtained that the damage deviation of the No. 4 fast charging cell is 0.75%; the damage deviation of the No. 5 fast charging cell is -0.27%; and the damage deviation of the No. 6 fast charging cell is -2.94%.

[0139] Finally, in this example, after calculating the corresponding damage deviation through the above steps, the damage consistency of the battery pack to be tested during the test can be further determined through the damage deviation, that is, the damage consistency of this test can be determined to be within 99.25% through each damage deviation.

[0140] That is, after statistical analysis, it was found that the damage degree of the three fast-charging cycle batteries and the ratio of normal batteries were all within 5%. The damage deviation was calculated, and it was found that under the condition of electrical damage, the damage consistency of the test method was 99.25%, which was greater than the test target requirement of not less than 90%, indicating that the test scheme can effectively evaluate the damage consistency of the battery cells under electrical damage.

[0141] In practice, each cell in a conventional battery pack, such as Figure 4 The capacity of each battery cell in the series 1 to series 3 shown in the figure changes as follows under normal cycle conditions, that is, under normal charging efficiency (such as 1C). Figure 4 shown.

[0142] Correspondingly, the corresponding cells in the fast charging cell group, such as Figure 5 The series 4 to series 6 shown in the figure have a capacity change of each cell, i.e., a cumulative damage, under fast charging, i.e., high efficiency (e.g., 2C) charge-discharge cycle. Figure 5 shown.

[0143] Depend on Figure 4 and Figure 5 As shown, by using the electrochemical damage test method provided by the present invention, the capacity change trend of each battery cell tends to be consistent, that is, the electrochemical damage of each battery cell presents a good consistency result.

[0144] It can be understood that the battery electrochemical damage consistency test provided by the present invention is carried out by performing multiple charge and discharge cycle operations on each battery cell in the battery pack to be tested, that is, the battery cells in the conventional battery pack are charged at conventional efficiency, and the battery cells in the fast-charging battery pack are quickly charged with high efficiency, and then discharged accordingly, and then the battery capacity test after multiple charge and discharge cycles is tested, so as to utilize the capacity changes of individual cells in the conventional battery pack and the fast-charging battery pack to determine the degree of electrochemical damage of the battery cells after multiple charge and discharge cycles, and finally, the damage degree of each fast-charging cell is compared horizontally to determine the difference in the degree of electrochemical damage of each battery cell under the same test conditions, that is, the damage deviation, to characterize the consistency of the electrochemical damage test taken.

[0145] The good consistency performance provides a feasible test method for testing electrochemical damage during the actual production and use of batteries. That is, it determines the effectiveness of the test method to ensure that during the battery development process, the batteries developed using this test method meet the relevant performance requirements, that is, the accuracy is higher, and provides a feasible test idea for the design and development of safe battery systems and methods.

[0146] On the other hand, Figure 6 As shown, the present invention provides a battery electrochemical damage consistency testing device, the device comprising:

[0147] The test module 210 is used to obtain test parameters, and the test parameters are used to make each battery cell in the battery group to be tested perform a charge and discharge cycle according to the test parameters. The battery group to be tested includes a conventional battery group and a fast-charge battery group. The conventional battery group includes at least one conventional battery cell, and the fast-charge battery group includes at least one fast-charge cell. The conventional battery cells and the fast-charge cells correspond to each other one by one to form at least one control group. The test parameters include the charging and discharging efficiency of each battery cell in the battery group to be tested, and the charging efficiency of the conventional battery cell is less than the charging efficiency of the fast-charge cell.

[0148] An acquisition module 220 is used to acquire the remaining capacity of each battery cell after performing a charge and discharge cycle;

[0149] The first determination module 230 is used to determine the damage deviation between two battery cells in the control group in the conventional battery pack and the fast-charging battery pack based on the initial capacity of each battery cell and the remaining capacity, wherein the damage deviation indicates the consistency of the corresponding electrochemical damage test when the battery pack to be tested performs a charge and discharge cycle based on the test parameters.

[0150] Optionally, in the battery electrochemical damage consistency testing method provided by an embodiment of the present invention, the test parameters include charging efficiency, discharging efficiency, charging cut-off voltage, discharging cut-off voltage and cycle period, and the charging efficiency for the conventional battery pack is lower than the charging efficiency for the fast-charging battery pack.

[0151] Optionally, the battery electrochemical damage consistency testing device provided by an embodiment of the present invention further includes:

[0152] The second determination module 240 is used to determine, based on the damage deviation, a consistency result of the electrochemical damage test corresponding to when the battery pack to be tested performs a charge and discharge cycle based on the test parameters.

[0153] Optionally, in the battery electrochemical damage consistency testing device provided by an embodiment of the present invention, the first determination module is specifically used for:

[0154] Determining a capacity retention rate of each battery cell according to the initial capacity and the remaining capacity;

[0155] Determining the battery damage of the fast-charging cells in each control group according to the capacity retention rate of each cell;

[0156] The damage deviation of each control group is determined according to the damage of each fast charging cell.

[0157] Optionally, in the battery electrochemical damage consistency testing device provided by an embodiment of the present invention, the first determination module is specifically used for:

[0158] The percentage of the remaining capacity of each battery cell to the initial capacity is calculated, and the percentage is used as the capacity retention rate of each battery cell.

[0159] Optionally, in the battery electrochemical damage consistency testing device provided by an embodiment of the present invention, the first determination module is specifically used for:

[0160] The difference between the capacity retention rate of the fast-charged cell in each control group and the capacity retention rate of the conventional cell was calculated as the damage of the fast-charged cell in each control group.

[0161] Optionally, in the battery electrochemical damage consistency testing device provided by an embodiment of the present invention, the first determination module is specifically used for:

[0162] Calculate the mean value of the damage deviation of each fast charging cell in each control group;

[0163] The difference between the damage of the fast-charging cells in each control group and the mean is calculated as the damage deviation of each fast-charging cell.

[0164] In an exemplary embodiment, a computer device, namely a data collection device, is provided. The computer device may be a server or a terminal, and its internal structure diagram may be as follows: Figure 7 As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store video tag processing data. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a meteorological data transmission method is implemented.

[0165] Those skilled in the art will understand that Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present invention, and does not constitute a limitation on the computer device to which the solution of the present invention is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0166] In an exemplary embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0167] In an exemplary embodiment, a computer-readable storage medium is provided, storing a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0168] In an exemplary embodiment, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0169] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in the present invention are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0170] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided by the present invention can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM may be in various forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).

[0171] The database involved in each embodiment provided by the present invention may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on blockchain, etc., but is not limited thereto. The processor involved in each embodiment provided by the present invention may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but is not limited thereto.

[0172] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0173] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A battery electrochemical damage consistency test method, characterized in that: The method comprises: Acquire test parameters, where the test parameters are used to make each battery cell in the battery group to be tested perform a charge and discharge cycle according to the test parameters, where the battery group to be tested includes a conventional battery group and a fast-charge battery group, where the conventional battery group includes at least one conventional battery cell, and the fast-charge battery group includes at least one fast-charge battery cell, where the conventional battery cells and the fast-charge batteries correspond one to one to form at least one control group, and where the test parameters include the charging efficiency and the discharging efficiency of each battery cell in the battery group to be tested, where the charging efficiency of the conventional battery cell is less than the charging efficiency of the fast-charge battery cell; Obtain the remaining capacity of each battery cell after the charge and discharge cycle is performed; Determine, according to the initial capacity of each battery cell and the remaining capacity, a damage deviation between two battery cells in a control group in the conventional battery pack and the fast-charge battery pack, wherein the damage deviation indicates the consistency of the corresponding electrochemical damage test when the battery pack to be tested performs a charge and discharge cycle based on the test parameters; Wherein, determining the damage deviation between two cells in a control group in the conventional battery pack and the fast-charge battery pack according to the initial capacity and the remaining capacity of each cell includes: Determining a capacity retention rate of each battery cell according to the initial capacity and the remaining capacity; The difference between the capacity retention rate of the fast-charged cell in each control group and the capacity retention rate of the conventional cell is calculated as the battery damage of the fast-charged cell in each control group; Calculate the mean value of battery damage of each fast charging cell in each control group; The difference between the battery damage of the fast-charging cells in each control group and the mean value is calculated as the damage deviation of each fast-charging cell.

2. The battery electrochemical damage consistency testing method according to claim 1, characterized in that: The test parameters also include a charge cut-off voltage, a discharge cut-off voltage and a cycle period, and the charging efficiency for the conventional battery pack is less than the charging efficiency for the fast-charge battery pack.

3. The battery electrochemical damage consistency testing method according to claim 2, characterized in that: The method further comprises: Based on the damage deviation, a consistency result of an electrochemical damage test corresponding to the battery pack to be tested when the battery pack to be tested performs a charge and discharge cycle based on the test parameters is determined.

4. The battery electrochemical damage consistency testing method according to claim 2, characterized in that: Determining the capacity retention rate of each battery cell according to the initial capacity and the remaining capacity includes: The percentage of the remaining capacity of each battery cell to the initial capacity is calculated, and the percentage is used as the capacity retention rate of each battery cell.

5. A battery electrochemical damage consistency test device, characterized in that: The device comprises: A test module, used to obtain test parameters, wherein the test parameters are used to make each battery cell in the battery group to be tested perform a charge and discharge cycle according to the test parameters, wherein the battery group to be tested includes a conventional battery group and a fast-charge battery group, wherein the conventional battery group includes at least one conventional battery cell, and the fast-charge battery group includes at least one fast-charge battery cell, wherein the conventional battery cells and the fast-charge batteries correspond one to one to form at least one control group, wherein the test parameters include the charging efficiency and the discharging efficiency of each battery cell in the battery group to be tested, wherein the charging efficiency of the conventional battery cell is less than the charging efficiency of the fast-charge battery cell; An acquisition module is used to obtain the remaining capacity of each battery cell after performing a charge and discharge cycle; A determination module, configured to determine a damage deviation between two cells in a control group in the conventional battery pack and the fast-charge battery pack according to the initial capacity of each cell and the remaining capacity, wherein the damage deviation indicates the consistency of the corresponding electrochemical damage test when the battery pack to be tested performs a charge and discharge cycle based on the test parameters; Wherein, the determination module is specifically used for: Determining a capacity retention rate of each battery cell according to the initial capacity and the remaining capacity; The difference between the capacity retention rate of the fast-charged cell in each control group and the capacity retention rate of the conventional cell is calculated as the damage of the fast-charged cell in each control group; Calculate the mean value of the damage deviation of each fast charging cell in each control group; The difference between the damage of the fast-charging cells in each control group and the mean is calculated as the damage deviation of each fast-charging cell.

6. A computer device, characterized in that: The computer device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the battery electrochemical damage consistency testing method according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that: The readable storage medium stores a computer program, and when the computer program is executed by a processor, the battery electrochemical damage consistency testing method according to any one of claims 1 to 4 is implemented.

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