Battery capacity loss test method, device, computer equipment and storage medium

Abstract

The application relates to a battery capacity loss test method, device, computer equipment and storage medium. The method comprises the following steps: performing constant voltage charging on a to-be-tested battery; obtaining a leakage current of a target electrode of the to-be-tested battery subjected to constant voltage charging for a preset test duration, the target electrode comprising an electrode with a working voltage in a platform region; and determining a capacity loss value of the target electrode of the to-be-tested battery based on the leakage current of the target electrode and the preset test duration. The capacity loss value of the target electrode of the to-be-tested battery can be measured through simple test operation and short-time electrical performance test, without the need to simulate to establish a positive and negative electrode side reaction model of the battery, and without the need to perform long-term electrical performance test on the to-be-tested battery, so that the test efficiency of battery capacity attenuation is greatly improved.

Description

Technical Field

[0001] The present application relates to the field of battery detection technology, and in particular to a battery capacity loss testing method, apparatus, computer equipment, storage medium, and computer program product. Background Art

[0002] In the battery industry, battery capacity is often used as an indicator to evaluate battery life. However, batteries experience continuous capacity degradation during use. Therefore, studying and analyzing the mechanisms of battery capacity degradation is crucial. Research has found that the life degradation of lithium-ion batteries is closely related to the internal chemical and electrochemical side reactions of lithium ions. The loss of active materials in the positive and negative electrodes of the battery is one of the main causes of battery life degradation.

[0003] At present, the methods for evaluating the loss of positive and negative electrode materials in batteries mainly include: simulating and establishing the side reaction models of the positive and negative electrodes of the battery, calculating the changes in the amount of lithium embedded in the positive and negative electrodes due to side reactions during battery storage through the models, or detecting the loss of positive and negative electrode materials through long-term electrical performance tests.

[0004] However, the above method requires a large number of experimental tests to obtain key parameters, which is time-consuming and the operation process is cumbersome, resulting in low test efficiency. Summary of the Invention

[0005] Based on this, it is necessary to provide a battery capacity loss testing method, device, computer equipment, computer-readable storage medium and computer program product that can improve testing efficiency in response to the above technical problems.

[0006] In a first aspect, the present application provides a method for testing battery capacity loss. The method comprises:

[0007] Performing constant voltage charging on the battery under test, and obtaining a leakage current of a target electrode of the battery under test during constant voltage charging for a preset test time, wherein the target electrode includes an electrode in a non-plateau region of the operating voltage;

[0008] Based on the leakage current of the target electrode and the preset test time, the capacity loss value of the target electrode of the battery to be tested is determined.

[0009] In the technical solution of the embodiment of the present application, the leakage current of the target electrode of the battery to be tested is obtained after the test time by performing constant voltage charging on the battery to be tested, and the capacity loss value of the target electrode is determined based on the leakage current of the target electrode and the preset test time. The entire process utilizes the high charging efficiency of constant voltage charging, shortens the capacity loss test time, and does not require the simulation to establish the positive and negative electrode side reaction model of the battery, nor does it require long-term electrical performance testing of the battery to be tested. The capacity loss value of the target electrode of the battery to be tested is measured through simple test operations and short-term electrical performance testing, greatly improving the test efficiency of battery capacity decay.

[0010] In some embodiments, if the battery to be tested still has an electrode whose operating voltage is in the plateau region, the method further includes:

[0011] The battery under test is fully discharged, charged, and fully discharged in sequence after constant voltage charging for a preset test time to obtain the total capacity loss value of the positive and negative electrodes;

[0012] According to the total capacity loss value of the positive and negative electrodes and the capacity loss value of the target electrode, the capacity loss value of the electrode whose operating voltage of the battery to be tested is in the platform area is obtained.

[0013] In the technical solution of the embodiment of the present application, by fully discharging, charging and fully discharging the battery to be tested in sequence, the capacity loss during the charging and storage process of the battery can be simulated to obtain the total capacity loss value of the positive and negative electrodes. Furthermore, based on the total capacity loss value of the positive and negative electrodes and the capacity loss value of the target electrode, the capacity loss value of the electrode whose working voltage is in the platform area is obtained, which solves the problem that the leakage current of one end electrode cannot be measured and thus the capacity loss value of the electrode cannot be evaluated, and realizes the effective distinction between the positive electrode capacity loss value and the negative electrode capacity loss value, which is conducive to the design of longer-lasting batteries.

[0014] In some embodiments, the battery under test, which is charged at a constant voltage according to a preset test time, is fully discharged, charged, and fully discharged in sequence to obtain the total capacity loss value of the positive and negative electrodes, including:

[0015] Fully discharging the battery under test that has been charged at a constant voltage for a preset test time, and recording the first full discharge capacity;

[0016] Charging the battery under test at a preset SOC test value, where the preset SOC test value is obtained based on the current SOC value of the battery under test;

[0017] Fully discharge the battery under test that has been charged according to the preset test time again, and record the second full discharge capacity;

[0018] The total capacity loss value of the positive and negative electrodes is obtained according to the first full discharge capacity and the second full discharge capacity.

[0019] In the technical solution of the embodiment of the present application, by charging the battery to be tested with a preset SOC test value and fully discharging the battery to be tested once before and after charging with the test SOC value, the actual capacity loss of the battery to be tested can be simulated more accurately, so that the full discharge capacity of the battery to be tested before and after charging can more accurately represent the total capacity loss value of the positive and negative electrodes.

[0020] In some embodiments, before performing constant voltage charging on the battery to be tested, the method further includes:

[0021] Obtain battery status data of the battery to be tested;

[0022] The target electrode of the battery to be tested is determined based on the battery status data. The battery status data includes a mapping relationship between SOC and OCV (Open Circuit Voltage), as well as the current SOC value.

[0023] In the technical solution of the embodiment of the present application, the battery status data such as the mapping relationship between SOC and OCV and the current SOC value can be used to simply and quickly determine the state of the electrode of the battery to be tested, and then determine the target electrode.

[0024] In some embodiments, if it is determined based on the battery status data that the target electrode of the battery to be tested includes a positive electrode and a negative electrode, then before performing constant voltage charging on the battery to be tested, the method further includes:

[0025] Send three-electrode battery assembly message;

[0026] When the three-electrode battery is assembled, the SOC value of the three-electrode battery is obtained, and the SOC value of the three-electrode battery is adjusted to a preset SOC test value, which is obtained based on the current SOC value of the battery to be tested;

[0027] The battery under test is charged at a constant voltage, and obtaining the leakage current of the target electrode of the battery under test during constant voltage charging according to a preset test time includes:

[0028] Read the open circuit voltage value corresponding to the preset SOC test value;

[0029] The three-electrode battery is charged at a constant voltage according to the open circuit voltage value, and the positive electrode leakage current and the negative electrode leakage current of the three-electrode battery charged at a constant voltage according to a preset test time are obtained.

[0030] In the technical solution of the embodiment of the present application, by assembling a three-electrode battery and charging the three-electrode battery at a constant voltage, the positive electrode leakage current and the negative electrode leakage current can be measured respectively, and then the positive electrode capacity loss value and the negative electrode capacity loss value can be evaluated respectively according to the positive electrode leakage current and the negative electrode leakage current.

[0031] In some embodiments, determining the capacity loss value of the target electrode of the battery to be tested based on the leakage current and the preset test duration includes:

[0032] The leakage current of the target electrode under the preset test time is integrated to obtain the capacity loss value of the target electrode of the battery to be tested.

[0033] In the technical solution of the embodiment of the present application, by integrating the leakage current of the target electrode under a preset test time, the capacity loss value of the target electrode of the battery to be tested can be obtained quickly and accurately.

[0034] In some embodiments, if the battery under test still has an electrode whose operating voltage is in the plateau region, the battery under test is subjected to constant voltage charging, and obtaining the leakage current of the target electrode of the battery under test subjected to constant voltage charging according to a preset test time includes:

[0035] Perform constant voltage charging on the battery under test multiple times according to a preset number of tests, and record the leakage current of the target electrode of the battery under test after each constant voltage charging according to a preset test duration;

[0036] Based on the leakage current and the preset test duration, the capacity loss value of the target electrode of the battery under test is determined including:

[0037] The leakage current of the target electrode of the battery to be tested under different preset test time lengths is integrated to determine the capacity loss value of the target electrode of the battery to be tested.

[0038] In the technical solution of the embodiment of the present application, by performing multiple constant-voltage charges on the battery to be tested, the capacity loss of the battery during actual use and storage can be more realistically simulated, and the leakage current at the target electrode under multiple preset test durations can be obtained. Then, by integrating the leakage current of the target electrode of the battery to be tested under different preset test durations, a more accurate value of the capacity loss value of the target electrode of the battery to be tested can be obtained.

[0039] In a second aspect, the present application also provides a battery capacity loss testing device. The device comprises:

[0040] The data acquisition module is used to perform constant voltage charging on the battery to be tested and obtain the leakage current of the target electrode of the battery to be tested during constant voltage charging according to a preset test time, wherein the target electrode includes an electrode whose operating voltage is in a non-platform area.

[0041] The capacity loss value determination module is used to determine the capacity loss value of the target electrode of the battery to be tested based on the leakage current of the target electrode and the preset test time.

[0042] In a third aspect, the present application provides a computer device. The computer device comprises a memory and a processor. The memory stores a computer program. The processor executes the computer program to implement the steps of the battery capacity loss testing method.

[0043] In a fourth aspect, the present application provides a computer readable storage medium. The computer readable storage medium stores a computer program. The computer program is executed by a processor to implement the steps of the battery capacity loss testing method.

[0044] In a fifth aspect, the present application provides a computer program product. The computer program product comprises a computer program. The computer program is executed by a processor to implement the steps of the battery capacity loss testing method.

[0045] The above description is only a summary of the technical solutions of the present application. In order to enable one skilled in the art to better understand the technical means of the present application and to implement the same according to the contents of the description, and in order to enable the above and other purposes, characteristics and advantages of the present application to be more apparent and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 Application environment diagram of the battery capacity loss testing method in some embodiments;

[0047] Figure 2 Flowchart of the battery capacity loss testing method in some embodiments;

[0048] Figure 3 Flowchart of the battery capacity loss testing method in some other embodiments;

[0049] Figure 4 Flowchart of the step of obtaining the total positive and negative electrode capacity loss value in some embodiments;

[0050] Figure 5 Detailed flowchart of the battery capacity loss testing method in some embodiments;

[0051] Figure 6 Detailed flowchart of the battery capacity loss testing method in some other embodiments;

[0052] Figure 7 Structure block diagram of the battery capacity loss testing device in some embodiments;

[0053] Figure 8 Structure block diagram of the battery capacity loss testing device in some other embodiments;

[0054] Figure 9 Internal structure diagram of the computer device in some embodiments. DETAILED DESCRIPTION

[0055] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0056] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0057] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0058] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0059] In the description of the embodiments of the present application, the term "plurality" refers to more than two (including two).

[0060] Currently, market developments indicate that batteries are becoming increasingly widely used. Batteries are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. As the application of power batteries continues to expand, market demand is also growing.

[0061] With the increasing demand for energy conservation, emission reduction, and environmental protection, the new energy vehicle industry has flourished in recent years. As a core component of electric vehicles, power batteries, such as battery capacity, directly impact their overall performance. To ensure proper operation and safety, batteries must be replaced after a certain mileage, demonstrating the importance of battery life assessment for electric vehicles.

[0062] However, batteries experience continuous capacity degradation during use, making it crucial to analyze the mechanisms of battery capacity degradation. Research has found that the lifespan degradation of lithium-ion batteries (hereinafter referred to as lithium batteries), commonly used in electric vehicles, is closely related to the internal chemical and electrochemical side reactions of lithium ions. Loss of active materials in the positive and negative electrodes is one of the primary causes of battery life degradation.

[0063] Traditional technologies for evaluating battery life degradation mainly include: simulating and establishing side reaction models of the positive and negative electrodes of the battery, using the models to calculate the changes in the amount of lithium inserted into the positive and negative electrodes due to side reactions during battery storage, or detecting the loss of positive and negative electrode materials through long-term electrical performance testing. However, all of the above methods are based on the perspective of evaluating the loss of active materials in the battery as a whole, without distinguishing between the loss of positive and negative active materials. In addition, the above methods require a large number of experimental tests to obtain key parameters, which is time-consuming and cumbersome, resulting in low test efficiency.

[0064] To improve the efficiency of battery life degradation testing, the applicant discovered that the leakage current at the positive and negative electrodes of a battery can represent the rate of side reactions at the positive and negative electrodes. Effectively distinguishing the degree of battery performance degradation caused by side reactions at the positive and negative electrodes, and enabling rapid evaluation of positive and negative electrode materials, can facilitate the design of batteries with longer lifespans. The applicant also noted that constant voltage charging offers the advantages of shorter charging times, lower energy consumption, and higher charging efficiency compared to the conventional constant current charging method.

[0065] Based on the above considerations, the applicant proposed a solution for evaluating electrode capacity loss based on leakage current during constant voltage charging testing. This involves performing constant voltage charging on the battery to be tested, obtaining the leakage current of the target electrode of the battery to be tested that is charged at a constant voltage according to a preset test duration, and then determining the capacity loss value of the target electrode of the battery to be tested based on the leakage current of the target electrode and the preset test duration. During the entire testing process, there is no need to simulate and establish battery positive and negative electrode side reaction models, nor is there a need to conduct long-term electrical performance testing on the battery to be tested. The operation is simpler, and the capacity loss value of the battery electrode to be tested can be measured through a short electrical performance test, greatly improving the efficiency of battery capacity attenuation testing.

[0066] It is understandable that the battery capacity loss test method of the present application is not only applicable to lithium batteries, but also to batteries with other positive electrodes made of intercalation materials, such as sodium ion batteries, potassium ion batteries, etc.; more specifically, it is applicable to batteries including but not limited to batteries with positive electrodes made of nickel cobalt manganese oxide ternary materials, nickel cobalt aluminum oxide ternary materials, lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium iron phosphate, lithium manganese iron phosphate, lithium-rich manganese-based materials, etc.

[0067] The battery capacity loss test method provided in the embodiment of the present application can be applied to Figure 1 In the application environment shown. Among them, the controller 102 performs test management and control on the battery capacity loss test device, and evaluates the side reaction capacity loss of the battery to be tested in the battery capacity loss test device 104. Specifically, the tester may send a test instruction to the controller 102, and the controller 102 responds to the test instruction to perform constant voltage charging on the battery to be tested. After constant voltage charging is performed according to a preset test time, the leakage current of the target electrode of the battery to be tested that is constant voltage charged for the preset test time is obtained. Then, based on the leakage current of the target electrode and the preset test time, the capacity loss value of the target electrode of the battery to be tested is determined, wherein the target electrode includes an electrode whose operating voltage is in a non-platform area.

[0068] In one embodiment, Figure 2 As shown, a battery capacity loss test method is provided, which is applied to Figure 1 The controller 102 in FIG. 1 is taken as an example to illustrate, including the following steps:

[0069] In step 200 , the battery to be tested is charged at a constant voltage to obtain a leakage current of a target electrode of the battery to be tested during constant voltage charging for a preset test time, wherein the target electrode includes an electrode whose operating voltage is in a non-plateau region.

[0070] The battery to be tested may be a lithium battery. Leakage current refers to the current value when the change in charging current decreases over time after the rated DC working voltage is applied to the capacitor. That is, the current when the current change is in a relatively stable state is determined as the leakage current. The leakage current of the target electrode can characterize the side reaction rate of the electrode. In this embodiment, the target electrode includes an electrode whose working voltage is in a non-platform area, that is, it may include a positive electrode and a negative electrode, or it may include only a positive electrode, or only a negative electrode, which can be determined specifically according to the battery state of the battery to be tested. Compared with constant current charging, constant voltage charging has the characteristics of short charging time and high charging efficiency. Therefore, in this embodiment, the battery to be tested may be subjected to constant voltage charging to complete rapid charging of the battery to be tested. Specifically, the capacity loss test device may be a charge and discharge instrument, such as Figure 1 As shown, the capacity loss test apparatus includes two voltmeters, two ammeters (Amperemeter 1 and Amperemeter 2), and a battery under test. The open circuit voltage of the battery under test is read, recorded as OCV1, and the battery is charged at a constant voltage source at OCV1. At this time, Amperemeter 1 outputs the leakage current of the target electrode at different times. After charging is completed, the battery under test is set aside for a preset test period, such as 10 days, and the leakage current is recorded from the test period, such as 1 to 10 days.

[0071] Step 400 : determining the capacity loss value of the target electrode of the battery to be tested based on the leakage current of the target electrode and a preset test duration.

[0072] In this embodiment, the capacity loss value refers to the capacity loss amount generated during the storage and use of the battery. The capacity loss value includes the side reaction capacity loss value and the capacity loss value caused by the generated by-products. The actual capacity loss amount is mainly the side reaction capacity loss value, and the side reaction capacity loss value refers to the capacity loss amount caused by the side reaction inside the battery. After obtaining the target leakage current, the capacity loss value of the target electrode of the battery to be tested can be determined based on the leakage current of the target electrode and the preset test time. Specifically, if the accuracy of the capacity loss test device is high enough and the value of the leakage current measured by the ammeter is accurate enough, the product of the leakage current of the target electrode and the preset test time can be obtained to determine the capacity loss value of the target electrode. If the accuracy of the capacity loss test device is at a normal level, the leakage current of the target electrode can be integrated with the preset test time, and the integration result can be determined as the capacity loss value of the target electrode.

[0073] In the technical solution of the embodiment of the present application, the leakage current of the target electrode of the battery to be tested is obtained after the test time by performing constant voltage charging on the battery to be tested, and the capacity loss value of the target electrode is determined based on the leakage current of the target electrode and the preset test time. The entire process utilizes the high charging efficiency of constant voltage charging, shortens the capacity loss test time, and does not require the simulation to establish the positive and negative electrode side reaction model of the battery, nor does it require long-term electrical performance testing of the battery to be tested. The capacity loss value of the target electrode of the battery to be tested is measured through simple test operations and short-term electrical performance testing, greatly improving the test efficiency of battery capacity decay.

[0074] like Figure 3 As shown, in some embodiments, step 400 includes: step 420, integrating the leakage current of the target electrode under a preset test time to obtain a capacity loss value of the target electrode of the battery to be tested.

[0075] In a specific implementation, the leakage current and the capacity loss value of the target electrode can be obtained by integrating the leakage current of the target electrode under a preset test duration. If the leakage current of the target electrode includes positive electrode leakage current and negative electrode leakage current, the positive electrode leakage current value and the negative electrode leakage current value under a preset test duration can be integrated to obtain the positive electrode capacity loss value ∫I_leak_neg.(t)dt and the negative electrode capacity loss value ∫I_leak_neg.(t)dt under the test duration.

[0076] In the technical solution of the embodiment of the present application, by integrating the leakage current of the target electrode under a preset test time, the capacity loss value of the target electrode of the battery to be tested can be obtained quickly and accurately.

[0077] like Figure 3As shown, in some embodiments, before constant voltage charging is performed on the battery to be tested, the method further includes: step 100, obtaining battery status data of the battery to be tested, and determining the target electrode of the battery to be tested based on the battery status data, wherein the battery status data includes a mapping relationship between SOC and OCV, and a current SOC value.

[0078] The battery status data includes the mapping relationship between SOC and OCV, as well as the current SOC value, SOH (State of Health), SOF (State of Function) or other battery status parameters. The mapping relationship between SOC and OCV can be a SOC-OCV curve, or a mapping relationship table between SOC and OCV. In this embodiment, the mapping relationship between SOC and OCV takes the discharge SOC-OCV curve of the positive electrode and the discharge SOC-OCV curve of the negative electrode of the battery to be tested as an example. The discharge SOC-OCV curve can be obtained by obtaining the current SOC value of the battery to be tested, and then obtaining the SOC-OCV curves of the positive and negative electrodes of the battery to be tested. In the SOC-OCV curve, each SOC value has a corresponding OCV value.

[0079] Specifically, the SOC and OCV curves take the positive electrode discharge SOC-OCV curve and the negative electrode discharge SOC-OCV curve as examples. The discharge curve of the lithium battery basically reflects the state of the electrode, which is the superposition of the changes in the states of the positive and negative electrodes. During the entire discharge process, the voltage curve of the lithium battery can be divided into the following three stages: 1. The terminal voltage of the battery drops rapidly in the initial stage. The greater the discharge rate, the faster the voltage drops. 2. The battery voltage enters a period of slow change. This period can be called the platform area of ​​the battery. The smaller the discharge rate, the longer the platform area lasts, the higher the platform voltage, and the slower the voltage drops. 3. When the battery is almost discharged, the battery load voltage begins to drop sharply until it reaches the discharge cut-off voltage. In this embodiment, according to the slope of each curve segment in the SOC-OCV curve (which can be regarded as a voltage drop), the SOC-OCV curve can be divided into a platform area, a non-platform area, and a transition area. Specifically, if the slope of a certain curve segment of the SOC-OCV curve is If the slope of a certain curve segment of the SOC-OCV curve is not 0 and has an obvious slope, then the curve segment is defined as the non-platform area (slope area) of the SOC-OCV curve, and the remaining curve segments are defined as transition areas.

[0080] In a specific implementation, the target electrode of the battery to be tested can be determined according to the battery status data. The method is as follows: reading the current SOC value of the battery to be tested, and then judging whether the voltage corresponding to the current SOC value is in the non-platform area of ​​the SOC-OCV curve of the negative electrode and the negative electrode SOC-OCV curve; if the voltage corresponding to the current SOC value is in the non-platform area of ​​the SOC-OCV curve of the positive electrode and in the platform area of ​​the SOC-OCV curve of the negative electrode, then the target electrode is determined to be the positive electrode; if the voltage corresponding to the current SOC value is in the platform area of ​​the SOC-OCV curve of the positive electrode and in the non-platform area of ​​the SOC-OCV curve of the negative electrode, then the target electrode is determined to be the negative electrode; if the voltage corresponding to the current SOC value is in the platform area of ​​the SOC-OCV curve of the positive electrode and in the platform area of ​​the SOC-OCV curve of the negative electrode, then the target electrode is determined to include both the positive electrode and the negative electrode.

[0081] In the technical solution of the embodiment of the present application, the target electrode can be determined simply and quickly through the current SOC value of the battery to be tested and the mapping relationship between SOC and OCV.

[0082] like Figure 3 As shown, in some embodiments, if the battery to be tested still has an electrode whose operating voltage is in the plateau region, the method further includes:

[0083] Step 600 : The battery to be tested, which is charged at a constant voltage according to a preset test time, is fully discharged, charged, and fully discharged in sequence to obtain the total capacity loss value of the positive and negative electrodes.

[0084] Step 800 , obtaining the capacity loss value of the electrode whose operating voltage of the battery to be tested is in the platform region according to the total capacity loss value of the positive and negative electrodes and the capacity loss value of the target electrode.

[0085] The total capacity loss value of the positive and negative electrodes refers to the sum of the positive electrode capacity loss value and the negative electrode capacity loss value. In actual applications, if the voltage enters a stage of slow change, the voltage change of the electrode is very small, so the leakage current of the electrode cannot be effectively obtained by constant voltage charging. Therefore, the present application provides a first capacity loss test method for testing the battery to be tested for the case where the target electrode includes a positive electrode and a negative electrode; and provides a second capacity loss test method for testing the battery to be tested for the case where the target electrode includes a positive electrode or a negative electrode. Specifically, the first capacity loss test method refers to assembling the battery to be tested into a three-electrode battery, and testing the positive electrode leakage current value and the negative electrode leakage current value of the three-electrode battery by a constant voltage charging method, and then evaluating the capacity loss of the positive and negative electrodes by the positive electrode leakage current value and the negative electrode leakage current value. The second capacity loss test method refers to a test method for testing the battery leakage current value by a constant voltage charging method, and obtaining the capacity loss value of the positive and negative electrodes of the battery by performing charge and discharge tests on the battery to be tested.

[0086] In this embodiment, for the target electrode including a positive electrode or a negative electrode, the above-mentioned second capacity loss test method is used to perform a capacity loss test on the battery to be tested. Specifically, after determining the capacity loss value of the target electrode according to the leakage current of the target electrode and the preset test time, the battery to be tested that is charged at a constant voltage according to the preset test time is fully discharged, charged, and fully discharged in sequence. By performing a charge and discharge test on the battery to be tested, the total capacity loss value of the positive and negative electrodes of the battery, that is, the positive and negative electrode capacity loss value, is obtained, and then the total capacity loss value caused by the positive and negative electrode side reactions is subtracted from the capacity loss value of the target electrode to obtain the capacity loss value of the other electrode. For example, if the target electrode is a positive electrode, the capacity loss value of the positive electrode is recorded as Q_loss_pos.(t), the total capacity loss value of the positive and negative electrodes is recorded as Q_loss_total(t), and the capacity loss value of the negative electrode is Q_loss_neg.(t)=Q_loss_total(t)-Q_loss_pos.(t).

[0087] Taking the example of determining whether the target electrode includes the positive electrode or the negative electrode according to the SOC-OCV curve of the positive and negative electrodes, the process of testing the battery to be tested can be: combining Figure 1 , place the positive and negative electrodes of the capacity loss test device to the positive and negative electrodes of the battery to be tested, disconnect switch 1, and then read the open circuit voltage value of the battery to be tested through the voltmeter, recorded as OCV1, then, the constant voltage source performs constant voltage charging on the battery to be tested with the read OCV1. At this time, the negative electrode voltage remains unchanged or changes very little, then only the ammeter 1 outputs the positive electrode leakage current at different times over time. In this process, the positive electrode leakage current when the current change state is balanced and stable is recorded as I_leak_pos._0, which characterizes the positive electrode side reaction rate. Then, the battery to be tested after constant voltage charging is fully discharged, charged, and fully discharged again in sequence to simulate the side reaction capacity loss process of the battery during charging and storage (storage), and record the positive electrode leakage current of the battery to be tested in the non-platform area during the corresponding preset test time, such as 3 days, to obtain the total capacity loss value Q_loss_total(t) of the positive and negative electrodes. Then, the positive electrode capacity loss value Q_loss_pos.(t) is obtained from the positive electrode leakage current and the preset test duration, and the negative electrode capacity loss value is Q_loss_neg.(t) = Q_loss_total(t) - Q_loss_pos.(t). It can be understood that if the positive electrode of the battery is determined to be in the platform area and the negative electrode is in the non-platform area according to the SOC-OCV curve of the positive and negative electrodes, the negative electrode leakage current is measured by constant voltage charging, and then the negative electrode capacity loss value is obtained from the negative electrode leakage current and the preset test duration. Next, the total positive electrode capacity loss value is subtracted from the negative electrode capacity loss value to obtain the positive electrode capacity loss value.

[0088] In the technical solution of the embodiment of the present application, by fully discharging, charging and fully discharging the battery to be tested in sequence, the capacity loss during the storage process of the battery can be simulated to obtain the total capacity loss value of the positive and negative electrodes. Furthermore, based on the total capacity loss value of the positive and negative electrodes and the capacity loss value of the target electrode, the capacity loss value of the electrode whose working voltage is in the platform area is obtained, which solves the problem that the leakage current of one end electrode cannot be measured and the capacity loss value of the electrode cannot be evaluated, and realizes the effective distinction between the positive electrode capacity loss value and the negative electrode capacity loss value, which is conducive to the design of longer-lasting batteries.

[0089] like Figure 4 As shown, in some embodiments, step 600 includes:

[0090] Step 620 : Fully discharge the battery to be tested that has been subjected to constant voltage charging according to a preset test time, and record a first fully discharged capacity.

[0091] Step 640 : charging the battery to be tested with a preset SOC test value, where the preset SOC test value is obtained based on the current SOC value of the battery to be tested.

[0092] Step 660 : Fully discharge the battery to be tested that has been charged according to the preset test time again, and record a second fully discharged capacity.

[0093] Step 680: Obtain the total capacity loss value of the positive and negative electrodes according to the first fully discharged capacity and the second fully discharged capacity.

[0094] Following the above embodiment, after constant voltage charging is completed, the process of fully discharging, charging, and fully discharging the battery under test that has been charged at constant voltage for a preset test duration can be as follows: the battery under test can be fully discharged first, and the fully discharged capacity of the battery under test in the fully discharged state is recorded to obtain a first fully discharged capacity, which is recorded as Q1. Then, the fully discharged battery under test is charged again, which can be according to the preset test duration and with a preset SOC storage value. The SOC storage value can be the current actual SOC value of the battery under test before the test, simulating the capacity loss process that occurs during the charging and storage process of the battery, recording the leakage current of the target electrode of the battery under test after charging, and establishing a corresponding relationship between the test duration and the leakage current of the target electrode. Then, the battery under test is fully discharged again, and the discharge capacity of the battery under test in the fully discharged state is recorded, which is recorded as the second discharge capacity Q2. Then, based on the first fully discharged capacity Q1 and the second fully discharged capacity Q2, the total capacity loss value of the positive and negative electrodes Q_loss_total(t) = Q1-Q2 is obtained. It is understandable that the test duration for charging the fully discharged battery to be tested at the preset SOC storage value may be equal to or different from the preset duration for constant voltage charging, depending on the specific circumstances.

[0095] In the technical solution of the embodiment of the present application, by charging the battery to be tested with a preset SOC test value and fully discharging the battery to be tested once before and after charging with the test SOC value, the actual capacity loss of the battery to be tested can be simulated more accurately, so that the full discharge capacity of the battery to be tested before and after charging can more accurately represent the total capacity loss value of the positive and negative electrodes.

[0096] like Figure 5 As shown, in some embodiments, if it is determined based on the battery status data that the target electrode of the battery to be tested includes a positive electrode and a negative electrode, then before performing constant voltage charging on the battery to be tested, the method further includes:

[0097] Step 120: Send a three-electrode battery assembly message.

[0098] Step 140 , when the three-electrode battery is assembled, obtain the SOC value of the three-electrode battery, and adjust the SOC value of the three-electrode battery to a preset SOC test value, where the preset SOC test value is obtained based on the current SOC value of the battery to be tested.

[0099] Step 200 includes: step 220, reading the open circuit voltage value corresponding to the preset SOC test value, performing constant voltage charging on the three-electrode battery with the open circuit voltage value, and obtaining the positive electrode leakage current and negative electrode leakage current of the three-electrode battery that is constantly charged at a preset test time.

[0100] Step 400 includes: step 420, integrating the positive electrode leakage current and the negative electrode leakage current of the battery under test under a preset test time, and determining the positive electrode capacity loss value and the negative electrode capacity loss value of the battery under test.

[0101] The three-electrode battery is designed to eliminate the large errors in electrode potential caused by polarization current. It includes a working electrode, a reference electrode and an auxiliary electrode (also known as a counter electrode). On the basis of the ordinary two-electrode system (working electrode and counter electrode), a reference electrode is introduced to stabilize the working electrode.

[0102] This embodiment describes the first capacity loss test method for testing the capacity loss of the battery to be tested. Specifically, the capacity loss test device can be a charge and discharge instrument, including two voltmeters, two ammeters and the battery to be tested. Figure 1, the capacity loss test of the battery to be tested by the first capacity loss test method can be: sending a three-electrode battery assembly message, and the tester configures and assembles the three-electrode battery based on the battery to be tested. It can be understood that the assembly of the three-electrode battery can also be assembled by a machine, or realized by a computer by building a three-electrode simulation model, which depends on the actual situation. Afterwards, the three-electrode battery is left to stand for a certain period of time, such as 20 days, until the battery is fully depolarized to reduce the polarization effect of the three-electrode battery. Then, the positive and negative electrodes of the capacity loss test device are connected to the positive and negative electrodes of the battery respectively, the reference electrode is connected to the reference electrode of the battery, the switch 1 is closed, and the message of the completion of the three-electrode battery assembly is fed back to the controller. Then, the controller obtains the SOC value of the three-electrode battery and adjusts the SOC value of the battery to be tested to a preset SOC test value through the charging and discharging equipment. The test SOC value can be the actual SOC value of the battery to be tested or a test value determined based on the actual SOC value. The battery open circuit voltage corresponding to the above preset SOC test value is read by the voltmeter, recorded as OCV1, and the battery is charged at a constant voltage with OCV1 through a constant voltage source. At this time, ammeter 1 outputs the positive electrode leakage current value at different times, recorded as I_leak_pos. The positive electrode leakage current value can represent the positive electrode side reaction rate. Ammeter 2 outputs the negative electrode leakage current value at different times, recorded as I_leak_neg. The negative electrode leakage current value can represent the negative electrode side reaction rate. Then, the positive electrode leakage current and negative electrode leakage current of the preset test time, such as 1-10 days, are obtained. Furthermore, the positive electrode leakage current value and the negative electrode leakage current value under the preset test time are integrated to obtain the positive electrode capacity loss value ∫I_leak_neg.(t)dt and the negative electrode capacity loss value ∫I_leak_neg.(t)dt under the test time.

[0103] In the technical solution of the embodiment of the present application, by assembling a three-electrode battery and charging the three-electrode battery at a constant voltage, the positive and negative electrode leakage currents under the test time are quickly measured, and then by integrating the positive and negative electrode leakage currents under the test time, the positive electrode capacity loss value and the negative electrode capacity loss value are obtained respectively. The operation is simple, and the positive and negative electrode capacity loss values ​​can be measured through a short electrical performance test, thereby improving the test efficiency.

[0104] like Figure 5 As shown, in some embodiments, if the battery to be tested still has an electrode whose operating voltage is in the plateau region, step 200 includes:

[0105] Step 240 , performing constant voltage charging on the battery under test multiple times according to a preset number of tests, and recording the leakage current of the target electrode of the battery under test after each constant voltage charging according to a preset test duration.

[0106] Step 400 includes: Step 440, performing an integration operation on the leakage current of the target electrode of the battery to be tested under different preset test time lengths to determine the capacity loss value of the target electrode of the battery to be tested.

[0107] The preset number of tests can be determined according to the accuracy of the test equipment, and is generally not less than 3 times. This embodiment is an explanation of the use of the second capacity loss test method to test the battery to be tested. In specific implementation, in order to ensure the accuracy of the capacity loss value, after determining the preset number of tests, the open circuit voltage value of the battery to be tested can be read, and the battery to be tested is charged at a constant voltage at the open circuit voltage value according to the preset test duration. After charging to the preset test duration, the open circuit voltage value of the battery to be tested is read again, and the battery to be tested is charged at a constant voltage at the open circuit voltage value according to the preset test duration. In this way, the above steps are repeatedly performed until the number of tests reaches the preset number of tests. In this way, the leakage current of the target electrode under multiple test durations is obtained, and then the leakage current of the target electrode under multiple test durations is integrated to obtain the capacity loss value of the target electrode. For example, if the leakage current of multiple target electrodes is taken as the stable value of the positive electrode leakage current I_leak_pos_t, and multiple preset test time lengths are t1, t2, and t3, then the relationship curve I_leak_pos._t and t can be constructed based on multiple I_leak_pos_t and multiple preset test time lengths. The area of ​​the I_leak_pos._t-t curve is integrated to obtain the positive electrode capacity loss value, which is recorded as Q_loss_pos.(t) = ∫I_leak_pos._tdt.

[0108] In the technical solution of the embodiment of the present application, by performing multiple constant-voltage charges on the battery to be tested, the capacity loss of the battery during actual use and storage can be more realistically simulated, and the leakage current at the target electrode under multiple preset test durations can be obtained. Then, by integrating the leakage current of the target electrode of the battery to be tested under different preset test durations, a more accurate value of the capacity loss value of the target electrode of the battery to be tested can be obtained.

[0109] In order to make a clearer description of the battery capacity loss test method provided in this application, the following Figure 6 and one A specific embodiment is described below, which includes the following steps:

[0110] Step 1: Obtain the discharge SOC-OCV curve of the positive electrode and the discharge SOC-OCV curve of the negative electrode of the battery to be tested.

[0111] Step 2: If, based on the slopes of the discharge SOC-OCV curves of the positive and negative electrodes, it is determined that the operating voltages of both the positive and negative electrodes of the battery under test are in the non-plateau region (slope region), the capacity loss detection method is determined to be the first capacity loss detection method, and the process proceeds to step 3-1. If it is determined that the operating voltage of one electrode (positive or negative electrode) of the battery under test is in the plateau region, the capacity loss detection method is determined to be the second capacity loss detection method, and the process proceeds to step 3-2.

[0112] Step 3-1-1: Send three-electrode assembly message.

[0113] Step 3-1-2: When the three-electrode battery is assembled, obtain the SOC value of the three-electrode battery, and adjust the SOC value of the three-electrode battery to a preset SOC test value.

[0114] Step 3-1-3: Read the open circuit voltage value corresponding to the preset SOC test value.

[0115] Step 3-1-4: Perform constant voltage charging on the three-electrode battery at the open circuit voltage value to obtain the positive electrode leakage current and the negative electrode leakage current at different times.

[0116] Step 3-1-5: Obtain the positive electrode leakage current and the negative electrode leakage current under the preset test time, and integrate the positive electrode leakage current and the negative electrode leakage current under the preset test time respectively to obtain the positive electrode capacity loss value and the negative electrode capacity loss value of the battery to be tested.

[0117] Step 3-2: Read the open circuit voltage of the battery under test.

[0118] In step 3-2-2, the battery to be tested is charged at a constant voltage for a period of time at an open circuit voltage value according to the preset test duration to obtain the leakage current of the target electrode at different times.

[0119] Step 3-2-3: Fully discharge the battery to be tested that has been subjected to constant voltage charging according to a preset test time, and record the first fully discharged capacity.

[0120] Step 3-2-4: Charge the battery to be tested with the preset SOC test value.

[0121] In step 3-2-5, the battery to be tested is charged for a preset test duration and then subjected to multiple constant voltage charges according to the preset test number of times, and the leakage current of the target electrode of the battery to be tested that is charged for a preset test duration is recorded each time, to obtain the leakage current of the target electrode under different test durations.

[0122] Step 3-2-6: Fully discharge the battery to be tested after multiple constant voltage charges again, and record the second full discharge capacity.

[0123] Step 3-2-7, obtaining a total capacity loss value of the positive and negative electrodes according to the first full discharge capacity and the second full discharge capacity.

[0124] Step 3-2-8, performing integral operation on the leakage current of the target electrode under a plurality of preset test durations to obtain a capacity loss value of the target electrode of the battery to be tested.

[0125] Step 3-2-9, obtaining a capacity loss value of the electrode in the platform region of the battery to be tested according to the capacity loss value of the target electrode of the battery to be tested and the total capacity loss value of the positive and negative electrodes.

[0126] It should be understood that, although each step in the flowchart involved in each embodiment as described above is displayed in sequence according to the arrow, these steps are not necessarily executed in the order indicated by the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other orders. Moreover, at least part of the steps in the flowchart involved in each embodiment as described above can include multiple steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily sequential, but can be alternately or alternately executed with at least part of other steps or steps or stages in other steps.

[0127] Based on the same inventive concept, the embodiments of the present application also provide a battery capacity loss testing device for implementing the above-mentioned battery capacity loss testing method. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, so the specific limitations in one or more battery capacity loss testing device embodiments provided below can refer to the limitations of the battery capacity loss testing method described above, which will not be repeated here.

[0128] In one embodiment, as shown in Figure 7 a battery capacity loss testing device is provided, comprising: a data acquisition module 710 and a capacity loss value method determination module 720, wherein:

[0129] The data acquisition module 710 is configured to perform constant voltage charging on the battery to be tested, and obtain the leakage current of the target electrode of the battery to be tested subjected to constant voltage charging for a preset test duration. The target electrode includes an electrode with working voltage in a non-platform region.

[0130] The capacity loss value determination module 720 is configured to determine the capacity loss value of the target electrode of the battery to be tested based on the leakage current of the target electrode and the preset test duration.

[0131] In the technical solution of the embodiment of the present application, the leakage current of the target electrode of the battery to be tested is obtained after the test time by performing constant voltage charging on the battery to be tested, and the capacity loss value of the target electrode is determined based on the leakage current of the target electrode and the preset test time. The entire process utilizes the high charging efficiency of constant voltage charging, shortens the capacity loss test time, and does not require the simulation to establish the positive and negative electrode side reaction model of the battery, nor does it require long-term electrical performance testing of the battery to be tested. The capacity loss value of the target electrode of the battery to be tested is measured through simple test operations and short-term electrical performance testing, greatly improving the test efficiency of battery capacity decay.

[0132] like Figure 8 As shown, in some embodiments, the device also includes a charge and discharge capacity testing module 730, which is used to fully discharge, charge, and fully discharge the battery to be tested, which is charged at a constant voltage according to a preset test time, in sequence, to obtain the total capacity loss value of the positive and negative electrodes, and according to the total capacity loss value of the positive and negative electrodes and the capacity loss value of the target electrode, obtain the capacity loss value of the electrode whose working voltage of the battery to be tested is in the platform area.

[0133] In the technical solution of the embodiment of the present application, by fully discharging, charging and fully discharging the battery to be tested in sequence, the capacity loss during the storage process of the battery can be simulated to obtain the total capacity loss value of the positive and negative electrodes. Furthermore, based on the total capacity loss value of the positive and negative electrodes and the capacity loss value of the target electrode, the capacity loss value of the electrode whose working voltage is in the platform area is obtained, which solves the problem that the leakage current of one end electrode cannot be measured and the capacity loss value of the electrode cannot be evaluated. It realizes the effective distinction between the positive electrode capacity loss value and the negative electrode capacity loss value, which is conducive to the design of longer-lasting batteries.

[0134] In some embodiments, the charge and discharge capacity test module 730 is also used to fully discharge the battery to be tested that is charged at a constant voltage according to a preset test time, record the first fully discharged capacity, charge the battery to be tested with a preset SOC test value, the preset SOC test value is obtained based on the current SOC value of the battery to be tested, and fully discharge the battery to be tested that is charged according to the preset test time again, record the second fully discharged capacity, and obtain the total capacity loss value of the positive and negative electrodes based on the first fully discharged capacity and the second fully discharged capacity.

[0135] In the technical solution of the embodiment of the present application, the charge and discharge capacity test module charges the battery to be tested at a preset SOC test value, and fully discharges the battery to be tested once before and after charging at the test SOC value, respectively. This can more accurately simulate the actual capacity loss of the battery to be tested, so that the full discharge capacity of the battery to be tested before and after charging can more accurately represent the total capacity loss value of the positive and negative electrodes.

[0136] In some embodiments, the device also includes a target electrode determination module 702 for obtaining battery status data of the battery to be tested, and determining the target electrode of the battery to be tested based on the battery status data. The battery status data includes a mapping relationship between SOC and OCV, and a current SOC value.

[0137] In the technical solution of the embodiment of the present application, by using battery state data such as the mapping relationship between SOC and OCV, it is possible to simply and quickly determine whether the electrodes of the battery to be tested are all in the non-platform area, and then determine the target electrode.

[0138] In some embodiments, the device also includes a three-electrode assembly module 704, which is used to send a three-electrode battery assembly message. When the three-electrode battery is assembled, the SOC value of the three-electrode battery is obtained, and the SOC value of the three-electrode battery is adjusted to a preset SOC test value, which is obtained based on the current SOC value of the battery to be tested; the data acquisition module 710 is also used to read the open circuit voltage value corresponding to the preset SOC test value, and perform constant voltage charging on the three-electrode battery with the open circuit voltage value, and obtain the positive leakage current and negative leakage current of the three-electrode battery that is constantly charged according to the preset test time.

[0139] In the technical solution of the embodiment of the present application, by assembling a three-electrode battery and charging the three-electrode battery at a constant voltage, the positive electrode leakage current and the negative electrode leakage current can be measured respectively, and then the positive electrode capacity loss value and the negative electrode capacity loss value can be evaluated respectively according to the positive electrode leakage current and the negative electrode leakage current.

[0140] In some embodiments, the capacity loss value determination module 720 is further configured to perform an integration operation on the leakage current of the target electrode during a preset test time to obtain the capacity loss value of the target electrode of the battery to be tested.

[0141] In the technical solution of the embodiment of the present application, by integrating the leakage current of the target electrode under a preset test time, the capacity loss value of the target electrode of the battery to be tested can be obtained quickly and accurately.

[0142] In some embodiments, the data acquisition module 710 is further configured to perform constant voltage charging on the battery under test multiple times according to a preset number of tests, and record the leakage current of the target electrode of the battery under test after each constant voltage charging according to a preset test duration;

[0143] The side reaction capacity loss determination module 720 is further configured to perform an integration operation on the leakage current of the target electrode of the battery under test at different preset test durations to determine the capacity loss value of the target electrode of the battery under test.

[0144] In the technical solution of the embodiment of the present application, by performing multiple constant-voltage charges on the battery to be tested, the side reaction capacity loss of the battery during actual use and storage can be more realistically simulated, and the leakage current at the target electrode under multiple preset test time lengths can be obtained. Then, by integrating the leakage current of the target electrode of the battery to be tested under different preset test time lengths, a more accurate value of the capacity loss value of the target electrode of the battery to be tested can be obtained.

[0145] Each module in the aforementioned capacity loss testing device can be implemented in whole or in part through software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor within a computer device in hardware form, or can be stored in a computer device memory in software form, allowing the processor to call and execute the corresponding operations of each module.

[0146] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 9As shown in the figure. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. Among them, the processor, the memory and the input / output interface are connected through the system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capability. 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 the mapping relationship between the positive and negative SOC and OCV of the battery to be tested, the preset SOC test value, the preset test duration and other data. The input / output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used to communicate with the external terminal through network connection. The computer program is executed by the processor to realize a battery capacity loss test method. It can be understood that in other embodiments, the computer device can also be a terminal, and the computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. Among them, the processor of the computer device is used to provide computing and control capability. 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 and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used for wired or wireless communication with the external terminal, and the wireless mode can be realized by WIFI, mobile cellular network, NFC (near field communication) or other technologies. The computer program is executed by the processor to realize a battery capacity loss test method.

[0147] Those skilled in the art can understand that, Figure 9 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different component arrangement.

[0148] In some embodiments, a computer device is provided, including a memory and a processor, the memory storing a computer program, and the processor executing the computer program to realize the steps in the above battery capacity loss test method.

[0149] In some embodiments, a computer readable storage medium is provided, which stores a computer program, and the computer program is executed by a processor to realize the steps in the above battery capacity loss test method.

[0150] In one embodiment, a computer program product is provided, comprising a computer program, which implements the steps in the above-mentioned battery capacity loss test method when executed by a processor.

[0151] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented 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 memory, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory may include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processor involved in the various embodiments provided herein may be, but are not limited to, a general-purpose processor, a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processor (DSP), a programmable logic unit (PLC), a data processing logic unit based on quantum computing, and the like.

[0152] The technical features of the above embodiments can 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.

[0153] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery capacity loss testing method, characterized in that: The method comprises: Performing constant voltage charging on the battery to be tested, and obtaining a leakage current of a target electrode of the battery to be tested during constant voltage charging for a preset test time, wherein the target electrode includes an electrode whose operating voltage is in a non-plateau region; Determining a capacity loss value of the target electrode of the battery to be tested based on the leakage current of the target electrode and the preset test duration; Wherein, when the electrode in the non-plateau area includes a positive electrode and a negative electrode, the battery to be tested is assembled into a three-electrode battery, and the positive electrode capacity loss and the negative electrode capacity loss of the battery to be tested are determined based on the positive electrode leakage current, the negative electrode leakage current, and the preset test time of the three-electrode battery; In the case where the electrode in the non-plateau region includes a positive electrode or a negative electrode, the capacity loss of the electrode in the non-plateau region is determined based on the leakage current of the electrode in the non-plateau region and the preset test time.

2. The method according to claim 1, characterized in that If the battery to be tested still has an electrode whose operating voltage is in the plateau region, the method further includes: The battery under test is fully discharged, charged, and fully discharged in sequence after constant voltage charging for a preset test time to obtain the total capacity loss value of the positive and negative electrodes; According to the total capacity loss value of the positive and negative electrodes and the capacity loss value of the target electrode, the capacity loss value of the electrode whose operating voltage of the battery to be tested is in the platform area is obtained.

3. The method according to claim 2, characterized in that The method of sequentially performing full discharge, charging, and full discharge on the battery to be tested that is subjected to constant voltage charging according to a preset test time to obtain the total capacity loss value of the positive and negative electrodes includes: Fully discharging the battery under test that has been charged at a constant voltage for a preset test time, and recording the first full discharge capacity; Charging the battery to be tested at a preset SOC test value, where the preset SOC test value is obtained based on a current SOC value of the battery to be tested; Fully discharge the battery under test that has been charged according to the preset test time again, and record the second full discharge capacity; The total capacity loss value of the positive and negative electrodes is obtained according to the first full discharge capacity and the second full discharge capacity.

4. The method according to claim 1, wherein Before performing constant voltage charging on the battery to be tested, the method further includes: Acquiring battery status data of the battery to be tested; The target electrode of the battery to be tested is determined according to the battery status data, wherein the battery status data includes a mapping relationship between SOC and OCV, and a current SOC value.

5. The method according to claim 4, characterized in that If it is determined according to the battery status data that the target electrode of the battery to be tested includes a positive electrode and a negative electrode, then before performing constant voltage charging on the battery to be tested, the method further includes: Send three-electrode battery assembly message; When the three-electrode battery is assembled, obtaining the SOC value of the three-electrode battery and adjusting the SOC value of the three-electrode battery to a preset SOC test value, wherein the preset SOC test value is obtained based on the current SOC value of the battery to be tested; The method of performing constant voltage charging on the battery to be tested and obtaining the leakage current of the target electrode of the battery to be tested during constant voltage charging for a preset test time includes: Reading the open circuit voltage value corresponding to the preset SOC test value; The three-electrode battery is charged at a constant voltage using the open circuit voltage value, and a positive electrode leakage current and a negative electrode leakage current of the three-electrode battery that is charged at a constant voltage according to a preset test time are obtained.

6. The method according to any one of claims 1 to 5, characterized in that The determining, based on the leakage current and the preset test duration, a capacity loss value of a target electrode of the battery to be tested includes: The leakage current of the target electrode under the preset test time is integrated to obtain the capacity loss value of the target electrode of the battery to be tested.

7. The method according to any one of claims 1 to 4, characterized in that If the battery under test still has an electrode whose operating voltage is in the platform region, the battery under test is subjected to constant voltage charging, and the leakage current of the target electrode of the battery under test subjected to constant voltage charging according to a preset test time is obtained, comprising: Performing constant-voltage charging on the battery under test multiple times according to a preset number of tests, and recording the leakage current of the target electrode of the battery under test after each constant-voltage charging according to a preset test duration; The determining, based on the leakage current and the preset test duration, a capacity loss value of a target electrode of the battery to be tested includes: An integration operation is performed on the leakage current of the target electrode of the battery to be tested under different preset test time lengths to determine the capacity loss value of the target electrode of the battery to be tested.

8. A battery capacity loss testing device, characterized in that: The device comprises: a data acquisition module, configured to perform constant voltage charging on a battery under test and acquire leakage current of a target electrode of the battery under test during constant voltage charging for a preset test duration, wherein the target electrode includes an electrode whose operating voltage is in a non-plateau region; a capacity loss value determining module, configured to determine a capacity loss value of the target electrode of the battery to be tested based on the leakage current of the target electrode and the preset test duration; The capacity loss value determination module is also used to: when the electrode in the non-platform area includes a positive electrode and a negative electrode, assemble the battery to be tested into a three-electrode battery, and determine the positive electrode capacity loss and negative electrode capacity loss of the battery to be tested based on the positive electrode leakage current, the negative electrode leakage current, and the preset test duration of the three-electrode battery; when the electrode in the non-platform area includes a positive electrode or a negative electrode, determine the capacity loss of the electrode in the non-platform area based on the leakage current of the electrode in the non-platform area and the preset test duration.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

11. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

Images