Method and system for testing single-core overvoltage protection of lithium ion battery

Abstract

The invention provides a lithium ion battery single-core overvoltage protection testing method and system, the testing system is applied to an upper computer in the testing system, the testing system further comprises an intelligent virtual battery and a battery management system BMS, the intelligent virtual battery comprises a plurality of battery cores, the battery cores are connected with the BMS, and the method comprises the following steps: responding to a testing starting instruction; establishing a charging loop between the intelligent virtual battery and the BMS, collecting a first voltage value of the battery cell through the BMS, triggering overvoltage protection for the battery cell in response to the first voltage value of the battery cell meeting an overvoltage protection triggering condition, obtaining a second voltage value of the battery cell collected by the BMS after the overvoltage protection is triggered for the battery cell, and sending the second voltage value to the intelligent virtual battery; and in response to the condition that the second voltage value of the battery cell meets the overvoltage protection relieving condition, relieving the overvoltage protection for the battery cell, and circularly triggering the overvoltage protection and relieving the overvoltage protection for other battery cells in the plurality of battery cells, so as to complete the test for each battery cell in the intelligent virtual battery.

Description

Technical Field

[0001] The present application relates to the technical field of lithium batteries, and in particular to a testing method and system for single-cell overvoltage protection of lithium-ion batteries. Background Art

[0002] With the rapid development of the lithium battery industry, the safety requirements for lithium batteries are becoming increasingly higher. In order to prevent the risk of thermal runaway of lithium batteries caused by overcharging of single-cell lithium batteries, it is necessary to test the single-cell overvoltage protection of lithium batteries.

[0003] At present, the traditional single-cell overvoltage protection test method requires the use of a battery pack, a battery management system (BMS) and a power supply, and the test is performed during the charging process of the battery pack.

[0004] However, the traditional single-cell overvoltage protection test method requires the battery pack to be charged to a certain state before testing can be performed, which makes the test time longer, and the method cannot accurately locate the battery cell in the battery pack that triggers the overvoltage protection, that is, it can only cover any one of the multiple battery cells in the battery pack, but not every battery cell, which makes the test accuracy low. Summary of the invention

[0005] In view of this, the purpose of the present application is to provide a testing method and system for overvoltage protection of a single-cell lithium-ion battery, which can trigger or release the overvoltage protection test of the battery cell in response to the voltage value of the battery cell collected by the BMS meeting the overvoltage protection triggering condition or release condition, and perform the same test on each other battery cell in a cycle, thereby reducing the test time through the intelligent virtual battery, and performing an overvoltage protection test on each battery cell in the intelligent virtual battery in response to the test start instruction, covering the test of each battery cell, thereby improving the accuracy of the test. In the first aspect, an embodiment of the present application provides a testing method for overvoltage protection of a single-cell lithium-ion battery, which is applied to a host computer in a test system, the test system also including an intelligent virtual battery and a battery management system BMS, the intelligent virtual battery including multiple battery cells, and the multiple battery cells are respectively connected to the BMS; the method includes:

[0006] In response to a test start instruction, a charging circuit is established between the smart virtual battery and the BMS, and a first voltage value of the battery cell is collected through the BMS;

[0007] In response to the first voltage value of the battery cell satisfying an overvoltage protection triggering condition, triggering overvoltage protection for the battery cell;

[0008] Obtaining a second voltage value of the battery cell collected by the BMS after overvoltage protection is triggered on the battery cell;

[0009] In response to the second voltage value of the battery cell satisfying an overvoltage protection release condition, releasing the overvoltage protection for the battery cell;

[0010] The overvoltage protection is triggered and released cyclically on other battery cells in the plurality of battery cells, so as to complete the test on each battery cell in the intelligent virtual battery.

[0011] In a possible implementation manner, before collecting the first voltage value of each battery cell in the plurality of battery cells by the BMS, the method includes:

[0012] The temperature of the battery cell is set according to a preset temperature, and the first voltage value of the battery cell is set according to a preset basic voltage value.

[0013] In a possible implementation, setting the temperature of the battery cell according to a preset temperature includes:

[0014] Get the mapping relationship table between the preset temperature and the battery cell resistance;

[0015] Determine the cell resistance corresponding to the preset temperature based on the mapping relationship table;

[0016] The temperature of the battery cell is set by determining the battery cell resistance.

[0017] In a possible implementation manner, after releasing the overvoltage protection for the battery cell in response to the second voltage value of the battery cell satisfying the overvoltage protection release condition, the method further includes:

[0018] The overvoltage protection of the battery cell is triggered again, and the battery cell that triggers the overvoltage protection is discharged to the BMS to release the overvoltage protection for the battery cell.

[0019] In a possible implementation, triggering the overvoltage protection on the battery cell again and discharging the battery cell that triggers the overvoltage protection to the BMS to release the overvoltage protection on the battery cell includes:

[0020] Closing the charging loop established between the smart virtual battery and the BMS, discharging the battery cell that triggers the overvoltage protection to the BMS, and acquiring a third voltage value of the battery cell;

[0021] In response to the third voltage value of the battery cell satisfying the overvoltage protection release condition, the overvoltage protection for the battery cell is released.

[0022] In a possible implementation manner, before the cycle triggers overvoltage protection on other cells in the plurality of cells and releases overvoltage protection to complete the test on each cell in the smart virtual battery, the method further includes:

[0023] The voltage value of the battery cell is restored to a preset basic voltage value.

[0024] In a second aspect, an embodiment of the present application further provides a test system for overvoltage protection of a single-cell lithium-ion battery, the test system comprising a host computer, an intelligent virtual battery and a battery management system BMS, the host computer is connected to the intelligent virtual battery, the intelligent virtual battery is connected to the battery management system, the intelligent virtual battery comprises a plurality of cells, and the plurality of cells are respectively connected to the battery management system;

[0025] The host computer is used to respond to the test start instruction, establish a charging circuit between the intelligent virtual battery and the battery management system, and collect the first voltage value of the battery cell through the battery management system; in response to the first voltage value of the battery cell meeting the overvoltage protection triggering condition, trigger the overvoltage protection of the battery cell; obtain the second voltage value of the battery cell collected by the BMS after the overvoltage protection is triggered on the battery cell; in response to the second voltage value of the battery cell meeting the overvoltage protection release condition, release the overvoltage protection for the battery cell; cyclically trigger the overvoltage protection and release the overvoltage protection for other battery cells in the multiple battery cells to complete the test of each battery cell in the intelligent virtual battery;

[0026] The battery management system is used to collect the first voltage value and the second voltage value of the battery cell under the control of the host computer.

[0027] In a possible implementation manner, the host computer is further configured to set the temperature of the battery cell according to a preset temperature; and set the first voltage value of the battery cell according to a preset basic voltage value.

[0028] In a possible implementation, the host computer is further used to obtain a mapping relationship table between preset temperatures and battery cell resistances; determine the battery cell resistance corresponding to the preset temperature based on the mapping relationship table; and set the temperature of the battery cell according to the determined battery cell resistance.

[0029] In a possible implementation manner, the host computer is further used to restore the voltage value of the battery cell to a preset basic voltage value.

[0030] A testing method and system for overvoltage protection of a single lithium-ion battery cell provided in an embodiment of the present application respond to a test start instruction, establish a charging circuit between an intelligent virtual battery and a BMS in response to the test start instruction, and collect a first voltage value of the battery cell through the BMS, and trigger overvoltage protection on the battery cell in response to the first voltage value of the battery cell satisfying an overvoltage protection triggering condition, obtain a second voltage value of the battery cell collected by the BMS after the overvoltage protection is triggered on the battery cell, and release the overvoltage protection for the battery cell in response to the second voltage value of the battery cell satisfying an overvoltage protection release condition, and trigger overvoltage protection on other battery cells in the multiple battery cells and release the overvoltage protection in a cycle to complete the test of each battery cell in the intelligent virtual battery. The present application can trigger or release the overvoltage protection test on the battery cell in response to the voltage value of the battery cell collected by the BMS meeting the overvoltage protection triggering condition or releasing condition, and perform the same test on each other battery cell in a cycle, thereby reducing the test time through the intelligent virtual battery, and performing the overvoltage protection test on each battery cell in the intelligent virtual battery in response to the test start instruction, covering the test of each battery cell, thereby improving the accuracy of the test.

[0031] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 is a flow chart of a test method for overvoltage protection of a single-cell lithium-ion battery according to an embodiment of the present application;

[0034] Figure 2 is a flow chart of a test method for overvoltage protection of a single-cell lithium-ion battery according to another embodiment of the present application;

[0035] Figure 3 It is a schematic diagram of the test method of single-core overvoltage protection;

[0036] Figure 4 It is a schematic diagram of the BMS connection relationship;

[0037] Figure 5 It is a structural schematic diagram of a testing system for overvoltage protection of a single-cell lithium-ion battery according to an embodiment of the present application. DETAILED DESCRIPTION

[0038] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art can add one or more other operations to the flowchart under the guidance of the content of the present application, or remove one or more operations from the flowchart.

[0039] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0040] It should be noted that the term "comprising" will be used in the embodiments of the present application to indicate the existence of the features declared thereafter, but does not exclude the addition of other features.

[0041] In order to prevent the risk of thermal runaway of a single-cell lithium battery due to overcharging, it is necessary to test the single-cell overvoltage protection of the lithium battery. The traditional single-cell overvoltage protection test method requires the use of a battery pack, a battery management system, and a power supply, etc., by testing the single-cell overvoltage protection during the charging process of the battery pack. However, this traditional single-cell overvoltage protection test method requires the battery pack to be charged to a certain state before testing, which makes the test time longer, and this method cannot accurately locate the battery cell in the battery pack that triggers the overvoltage protection, that is, it can only cover any one of the multiple cells in the battery pack, but not every cell, which makes the test accuracy low.

[0042] To address this problem, the present application provides a testing method and system for overvoltage protection of a single lithium-ion battery cell, which can trigger or release the overvoltage protection test on the battery cell in response to the voltage value of the battery cell collected by the BMS meeting the overvoltage protection triggering condition or release condition, and perform the same test on each other battery cell in a cycle, thereby reducing the testing time through the intelligent virtual battery, and performing an overvoltage protection test on each battery cell in the intelligent virtual battery in response to a test start instruction, thereby covering the test of each battery cell, thereby improving the accuracy of the test.

[0043] Figure 1 The present invention is a flow chart of a test method for overvoltage protection of a single-cell lithium-ion battery according to an embodiment of the present invention. The test method for overvoltage protection of a single-cell lithium-ion battery is applied to a host computer in a test system. The test system also includes an intelligent virtual battery and a battery management system BMS. The intelligent virtual battery includes multiple cells, and the multiple cells are connected to the BMS respectively, such as Figure 1 As shown, the test method for overvoltage protection of a single-cell lithium-ion battery in an embodiment of the present application may specifically include:

[0044] S101, responding to a test start instruction, establishing a charging circuit between the intelligent virtual battery and the BMS, and collecting a first voltage value of the battery cell through the BMS.

[0045] In the embodiment of the present application, the test start instruction is an instruction on the host computer that indicates the start of the test, the first voltage value is the cell voltage value of one of the multiple cells, and the charging circuit is a circuit for charging the battery management system (BMS). In response to the test start instruction, the host computer starts the overvoltage protection test, establishes a charging circuit between the smart virtual battery and the BMS, and collects the first voltage value of one of the multiple cells through the BMS for subsequent processing. It should be noted that the BMS can collect the first voltage value of the cell, that is, the voltage information, in real time, and charges the BMS by establishing a charging circuit between the smart virtual battery and the BMS, thereby ensuring that the BMS can work normally and achieving a simulation of the lithium-ion battery charging scenario in reality.

[0046] S102 , in response to a first voltage value of the battery cell satisfying an overvoltage protection triggering condition, triggering overvoltage protection on the battery cell.

[0047] In the embodiment of the present application, the first voltage value of the battery cell collected by the BMS in step S101 is detected. If the first voltage value of the battery cell meets the overvoltage protection triggering condition, the overvoltage protection is triggered for the battery cell. It should be noted that the overvoltage protection triggering condition is the condition that can cause the battery cell to trigger overvoltage protection. Optionally, a single-cell overvoltage protection value can be pre-set as the overvoltage protection triggering condition, which is determined by comparing the voltage of the battery cell with the single-cell overvoltage protection value. That is, when the first voltage value of the battery cell is greater than or equal to the single-cell overvoltage protection value, the overvoltage protection is triggered for the battery cell. For example, the single-cell overvoltage protection value is set to 3.6V, and when the first voltage value of the battery cell is greater than or equal to 3.6V, the overvoltage protection is triggered for the battery cell.

[0048] S103, obtaining a second voltage value of the battery cell collected by the BMS after overvoltage protection is triggered on the battery cell.

[0049] In the embodiment of the present application, after the overvoltage protection of the battery cell is triggered, the second voltage value of the battery cell collected by the BMS is acquired for subsequent processing.

[0050] S104 , in response to the second voltage value of the battery cell satisfying an overvoltage protection release condition, releasing the overvoltage protection for the battery cell.

[0051] In the embodiment of the present application, the second voltage value of the battery cell collected by the BMS obtained in step S103 is judged, and if the second voltage value of the battery cell meets the overvoltage protection release condition, the overvoltage protection for the battery cell is released. It should be noted that the overvoltage protection release condition is the condition for releasing the overvoltage protection state of the battery cell. Optionally, a single-cell overvoltage protection recovery value can be pre-set as the overvoltage protection release condition, and the voltage of the battery cell and the single-cell overvoltage protection recovery value are compared to determine that when the second voltage value of the battery cell is less than or equal to the single-cell overvoltage protection value, the overvoltage protection for the battery cell is released.

[0052] As a possible implementation, the overvoltage protection of the battery cell can be triggered by reducing the voltage of the battery cell that triggers the overvoltage protection to the single-cell overvoltage protection recovery value corresponding to the overvoltage protection release condition, that is, reducing the voltage of the battery cell to less than or equal to the single-cell overvoltage protection recovery value.

[0053] As another possible implementation, whether to release the overvoltage protection for the battery cell can be determined by detecting whether a discharge current is generated in the battery cell after the overvoltage protection is triggered. Specifically, if a discharge current exists, the overvoltage protection for the battery cell is released. This will not be elaborated in detail.

[0054] S105 , cyclically triggering overvoltage protection on other cells in the plurality of cells and releasing the overvoltage protection, so as to complete the test on each cell in the intelligent virtual battery.

[0055] In the embodiment of the present application, the above-mentioned overvoltage protection test process is executed cyclically for each other battery cell in the smart virtual battery, that is, the overvoltage protection of the battery cell is triggered and the overvoltage protection is released for the battery cell, and by testing each battery cell, the test of all the batteries in the smart virtual battery is completed. Thus, by cyclically triggering the overvoltage protection and releasing the overvoltage protection for other batteries, the overvoltage protection test method covers each battery cell in the smart virtual battery.

[0056] The test method for overvoltage protection of a single lithium-ion battery cell provided in an embodiment of the present application responds to a test start instruction, establishes a charging circuit between an intelligent virtual battery and a BMS, and collects a first voltage value of the battery cell through the BMS. In response to the first voltage value of the battery cell satisfying an overvoltage protection triggering condition, overvoltage protection is triggered on the battery cell. After the overvoltage protection is triggered on the battery cell, a second voltage value of the battery cell collected by the BMS is obtained. In response to the second voltage value of the battery cell satisfying an overvoltage protection release condition, overvoltage protection for the battery cell is released. Overvoltage protection is triggered and released for other battery cells in the multiple battery cells in a cycle to complete the test of each battery cell in the intelligent virtual battery. The test method for overvoltage protection of a single-cell lithium-ion battery of the present application can trigger or release the overvoltage protection test on the cell in response to the voltage value of the cell collected by the BMS satisfying the overvoltage protection triggering condition or release condition, and perform the same test on each other cell in a cycle, thereby reducing the test time through the intelligent virtual battery, and performing the overvoltage protection test on each cell in the intelligent virtual battery in response to the test start instruction, thereby covering the test of each cell, thereby improving the accuracy of the test.

[0057] Further, such as Figure 2 As shown, before "collecting the first voltage value of the battery cell by the BMS" in step S101 in the above embodiment, the method may further include the following steps:

[0058] S201, setting the temperature of the battery cell according to a preset temperature.

[0059] In the embodiment of the present application, the preset temperature is a pre-set temperature that meets the requirements of the test loop. Before the BMS collects the first voltage value of the battery cell, the temperature of the battery cell needs to be set according to the preset temperature to ensure that the battery cell can work normally. It can be understood by those skilled in the art that the battery cell needs to work normally within a certain temperature range. For example, conventional lithium batteries work normally within a temperature range of -20℃ to 60℃, and the preset temperature is selected within this range.

[0060] It should be noted that the present application does not impose too many restrictions on the specific method of setting the battery cell temperature according to the preset temperature, and it can be set according to actual conditions.

[0061] As a possible implementation method, a mapping relationship table between a preset temperature and a cell resistance is obtained, the cell resistance corresponding to the preset temperature is determined based on the mapping relationship table, and the temperature of the cell is set by the determined cell resistance. The mapping relationship table characterizes the correspondence between the temperature and the cell resistance, selects the temperature corresponding to the preset temperature in the mapping relationship table, further determines the cell resistance corresponding to the temperature in the mapping relationship table, and sets the temperature of the cell by the determined cell resistance. It can be understood by those skilled in the art that the temperature of the cell can be adjusted by adjusting the resistance of the cell.

[0062] S202, setting a first voltage value of the battery cell according to a preset basic voltage value.

[0063] In the embodiment of the present application, the preset basic voltage is a pre-set basic voltage of the battery cell that meets the test requirements, and the first voltage value of the battery cell is set according to the preset basic voltage value, that is, the voltage value of the battery cell is set to the preset basic voltage value as the first voltage value.

[0064] Further, after step S104 in the above embodiment, “in response to the second voltage value of the battery cell satisfying the overvoltage protection release condition, the overvoltage protection for the battery cell is released”, the test method for overvoltage protection of a single-cell lithium-ion battery in the embodiment of the present application may further include the following steps:

[0065] The overvoltage protection of the battery cell is triggered again, and the battery cell that triggers the overvoltage protection is discharged to the BMS to release the overvoltage protection for the battery cell.

[0066] In the embodiment of the present application, after the overvoltage protection is triggered for the first time and the overvoltage protection is released for the battery cell, the overvoltage protection needs to be triggered for the battery cell again, and the battery cell that triggered the overvoltage protection is discharged to release the overvoltage protection for the battery cell. Optionally, as mentioned above, the voltage of the battery cell can still be set to a preset basic voltage so that the voltage of the battery cell meets the overvoltage protection triggering condition.

[0067] As a possible implementation method, the charging circuit established between the smart virtual battery and the BMS is closed, the battery cell that triggers the overvoltage protection is discharged to the BMS, and the third voltage value of the battery cell is obtained; in response to the third voltage value of the battery cell satisfying the overvoltage protection release condition, the overvoltage protection for the battery cell is released. It should be noted that when releasing the overvoltage protection state of the battery cell that triggers the overvoltage protection again, it is necessary to first close the charging circuit established between the smart virtual battery and the BMS, that is, turn off the charging power supply of the BMS, stop charging the BMS, and start discharging the BMS, that is, use the virtual battery as a load, and when the overvoltage protection release condition is met, the overvoltage protection for the battery cell is released.

[0068] Furthermore, before step S105 of the above embodiment "cyclically triggering overvoltage protection and releasing overvoltage protection for other cells in the multiple cells to complete the test of each cell in the intelligent virtual battery", the test method for overvoltage protection of a single-cell lithium-ion battery in the embodiment of the present application may further include the following steps:

[0069] The voltage value of the recovery cell is the preset basic voltage value.

[0070] In an embodiment of the present application, after the overvoltage protection of the battery cell is triggered and released twice, that is, after the battery cell that triggered the overvoltage protection again releases the overvoltage protection through discharge, the voltage of the battery cell is restored to the preset basic voltage described previously, that is, the battery cell is in the initial state of the overvoltage protection test. At this time, after the voltage value of the battery cell is restored to the preset basic voltage value, it indicates that the overvoltage protection test process for this battery cell is completed, and then the above-mentioned overvoltage protection test process, that is, the process of triggering overvoltage protection and releasing overvoltage protection, is started in a cycle for each of the other battery cells in the multiple battery cells.

[0071] To clearly illustrate the test method for overvoltage protection of a single-cell lithium-ion battery in the present application, Figure 3-Figure 4 Describe in detail.

[0072] Figure 3 This is a schematic diagram of the test method for single-core overvoltage protection. Figure 3 As shown, when performing a single-cell overvoltage protection test on the battery cells in the smart virtual battery, firstly, the BMS is wired, that is, a charging circuit is established between the BMS and the smart virtual battery to charge the BMS. After the BMS is wired, the host computer software is logged in, and a pre-set script is loaded on the host computer software, and the test is started. The completion of the script execution indicates the completion of the overvoltage protection test of each battery cell in the smart virtual battery.

[0073] Among them, the script represents the test process of the above-mentioned overvoltage protection and the script can be edited before execution to change the instruction content therein. The script includes instruction content corresponding to various steps of the test process, such as: temperature setting, starting the charging circuit, setting the battery cell voltage to a preset basic voltage to trigger voltage protection, lowering the battery cell voltage to release the voltage protection, triggering the voltage protection again, closing the charging circuit and discharging the BMS to release the voltage protection, restoring the battery cell voltage to a preset basic value, and cyclically executing the above steps for other battery cells. The test ends when all the battery cells are cycled.

[0074] It should be noted that when setting the cell voltage to a preset basic voltage to trigger voltage protection, the preset basic voltage can be increased or decreased in steps of 10mv. When the cell voltage after increase or decrease based on the preset basic voltage meets the overvoltage protection triggering condition, that is, it is greater than or equal to the single-cell overvoltage protection value, the overvoltage protection of the cell is triggered. Similarly, when releasing the first overvoltage protection of the cell, the voltage is still increased or decreased under the premise of a voltage step of 10mv until the cell voltage meets the overvoltage protection release condition, that is, it is less than or equal to the single-cell overvoltage protection recovery value, and the overvoltage protection for the cell is released. When triggering the second overvoltage protection for the cell, the voltage can be directly increased in steps of 10mv based on the above cell voltage, that is, increased by 10mv, until the cell voltage meets the overvoltage protection triggering condition.

[0075] Figure 4 This is a schematic diagram of the BMS connection relationship, such as Figure 4 As shown, on the virtual battery panel, the 9 nodes B0-B8 of the virtual battery represent the 8 batteries of the smart virtual battery, that is, every two nodes represent one battery cell. For example, B0-B1 represents one battery cell, and different batteries are represented by connecting different nodes to the BMS protection board; on the virtual temperature panel, the temperature of the battery cell is set by the 5 nodes T0-T4, and different temperatures are represented by connecting different nodes to the BMS protection board; on the power interface panel, a loop can be formed with the BMS, for example, C+, P-, B-, and C- form a loop, that is, it flows from C+ to P-, B-, and finally reaches C-.

[0076] Figure 5 FIG. 1 is a schematic diagram of a structure of a test system for overvoltage protection of a single-cell lithium-ion battery according to an embodiment of the present application. Figure 5 As shown, the lithium-ion battery single-cell overvoltage protection test system 500 of the embodiment of the present application may specifically include: a host computer 501, an intelligent virtual battery 502 and a battery management system BMS503.

[0077] The host computer 501 is connected to the intelligent virtual battery 502 , the intelligent virtual battery 502 is connected to the battery management system 503 , the intelligent virtual battery 502 includes multiple battery cells, and the multiple battery cells are respectively connected to the battery management system 503 .

[0078] The host computer 501 is used to respond to the test start instruction, establish a charging circuit between the intelligent virtual battery 502 and the battery management system 503, and collect the first voltage value of each battery cell in the multiple battery cells through the battery management system; in response to the first voltage value of the battery cell meeting the overvoltage protection triggering condition, trigger the overvoltage protection of the battery cell; obtain the second voltage value of the battery cell collected by the BMS after the overvoltage protection is triggered on the battery cell; in response to the second voltage value of the battery cell meeting the overvoltage protection release condition, release the overvoltage protection for the battery cell; cyclically trigger the overvoltage protection for other battery cells in the multiple battery cells and release the overvoltage protection to complete the test of each battery cell in the intelligent virtual battery.

[0079] The battery management system 503 is used to collect the first voltage value of each battery cell in the multiple battery cells under the control of the host computer.

[0080] Furthermore, the host computer 501 is also used to set the temperature of the battery cell according to a preset temperature before collecting the first voltage value of the battery cell through the BMS, and to set the first voltage value and the second voltage value of the battery cell according to a preset basic voltage value.

[0081] Furthermore, the host computer 501 is also used to obtain a mapping relationship table between a preset temperature and a cell resistance; determine the cell resistance corresponding to the preset temperature based on the mapping relationship table; and set the temperature of the cell according to the determined cell resistance.

[0082] Furthermore, the upper computer 501 is also used to trigger the overvoltage protection of the battery cell again after releasing the overvoltage protection for the battery cell in response to the second voltage value of the battery cell satisfying the overvoltage protection release condition, and discharge the battery cell that triggered the overvoltage protection to the battery management system 503 to release the overvoltage protection for the battery cell.

[0083] Furthermore, the host computer 501 is also used to close the charging circuit established between the intelligent virtual battery 502 and the battery management system 503, discharge the battery cell that triggers the overvoltage protection to the battery management system 503, and obtain the third voltage value of the battery cell; in response to the third voltage value of the battery cell meeting the overvoltage protection release condition, the overvoltage protection for the battery cell is released.

[0084] Furthermore, the host computer 501 is also used to restore the voltage value of the battery cell to a preset basic voltage value.

[0085] In the test system for overvoltage protection of a single lithium-ion battery cell provided in an embodiment of the present application, the upper computer 501 responds to a test start instruction, establishes a charging circuit between the intelligent virtual battery 502 and the battery management system 503, and collects a first voltage value of the battery cell through the battery management system 503. In response to the first voltage value of the battery cell satisfying the overvoltage protection triggering condition, the overvoltage protection is triggered for the battery cell. After the overvoltage protection is triggered for the battery cell, the second voltage value of the battery cell collected by the battery management system 503 is obtained. In response to the second voltage value of the battery cell satisfying the overvoltage protection release condition, the overvoltage protection for the battery cell is released. The overvoltage protection is triggered and released for other battery cells in the multiple battery cells in a cycle to complete the test for each battery cell in the intelligent virtual battery 502. The lithium-ion battery single-cell overvoltage protection test system of the present application can trigger or release the overvoltage protection test on the battery cell in response to the voltage value of the battery cell collected by the battery management system BMS meeting the overvoltage protection triggering condition or release condition, and perform the same test on each other battery cell in a cycle, thereby reducing the test time through the intelligent virtual battery, and performing the overvoltage protection test on each battery cell in the intelligent virtual battery in response to the test start instruction, covering the test of each battery cell, thereby improving the accuracy of the test.

[0086] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the system and device described above can refer to the corresponding process in the method embodiment, and will not be repeated in this application. In the several embodiments provided in this application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation. For example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0087] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0088] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0089] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the deployment method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard drives, ROM, RAM, magnetic disks, or optical disks.

[0090] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A test method for overvoltage protection of a single-cell lithium-ion battery, characterized in that: The host computer is applied to a test system, wherein the test system further comprises an intelligent virtual battery and a battery management system BMS, wherein the intelligent virtual battery comprises a plurality of battery cells, and the plurality of battery cells are respectively connected to the BMS; and the method comprises: In response to a test start instruction, a charging circuit is established between the smart virtual battery and the BMS, and a first voltage value of the battery cell is collected through the BMS; In response to the first voltage value of the battery cell satisfying an overvoltage protection triggering condition, triggering overvoltage protection for the battery cell; Obtaining a second voltage value of the battery cell collected by the BMS after overvoltage protection is triggered on the battery cell; In response to the second voltage value of the battery cell satisfying an overvoltage protection release condition, releasing the overvoltage protection for the battery cell; The overvoltage protection is triggered and released cyclically on other battery cells in the plurality of battery cells, so as to complete the test on each battery cell in the intelligent virtual battery.

2. The testing method according to claim 1, characterized in that: Before collecting the first voltage value of the battery cell through the BMS, the method includes: The temperature of the battery cell is set according to a preset temperature, and the first voltage value of the battery cell is set according to a preset basic voltage value.

3. The testing method according to claim 2, characterized in that: The step of setting the temperature of the battery cell according to a preset temperature includes: Get the mapping relationship table between the preset temperature and the battery cell resistance; Determine the cell resistance corresponding to the preset temperature based on the mapping relationship table; The temperature of the battery cell is set by determining the battery cell resistance.

4. The testing method according to claim 1, characterized in that: After releasing the overvoltage protection for the battery cell in response to the second voltage value of the battery cell satisfying the overvoltage protection release condition, the method further includes: The overvoltage protection of the battery cell is triggered again, and the battery cell that triggers the overvoltage protection is discharged to the BMS to release the overvoltage protection for the battery cell.

5. The testing method according to claim 4, characterized in that: The overvoltage protection is triggered again on the battery cell, and the battery cell that triggers the overvoltage protection is discharged to the BMS to release the overvoltage protection for the battery cell, including: Closing the charging loop established between the smart virtual battery and the BMS, discharging the battery cell that triggers the overvoltage protection to the BMS, and acquiring a third voltage value of the battery cell; In response to the third voltage value of the battery cell satisfying the overvoltage protection release condition, the overvoltage protection for the battery cell is released.

6. The testing method according to claim 1, characterized in that: Before the cycle triggers overvoltage protection on other cells in the plurality of cells and releases overvoltage protection to complete the test on each cell in the smart virtual battery, the method further includes: The voltage value of the battery cell is restored to a preset basic voltage value.

7. A test system for overvoltage protection of a single-cell lithium-ion battery, characterized in that: The test system includes a host computer, an intelligent virtual battery and a battery management system BMS, the host computer is connected to the intelligent virtual battery, the intelligent virtual battery is connected to the battery management system, the intelligent virtual battery includes multiple battery cells, and the multiple battery cells are respectively connected to the battery management system; The host computer is used to respond to the test start instruction, establish a charging circuit between the intelligent virtual battery and the battery management system, and collect the first voltage value of the battery cell through the battery management system; In response to the first voltage value of the battery cell satisfying the overvoltage protection triggering condition, overvoltage protection is triggered for the battery cell; after the overvoltage protection is triggered for the battery cell, a second voltage value of the battery cell collected by the BMS is acquired; in response to the second voltage value of the battery cell satisfying the overvoltage protection release condition, overvoltage protection for the battery cell is released; overvoltage protection is triggered and released for other battery cells in the multiple battery cells in a cycle to complete the test for each battery cell in the smart virtual battery; The battery management system is used to collect the first voltage value and the second voltage value of the battery cell under the control of the host computer.

8. The test system according to claim 7, characterized in that: The host computer is further used to set the temperature of the battery cell according to a preset temperature; and to set the first voltage value of the battery cell according to a preset basic voltage value.

9. The test system according to claim 8, characterized in that: The host computer is also used to obtain a mapping relationship table between a preset temperature and a cell resistance; determine the cell resistance corresponding to the preset temperature based on the mapping relationship table; and set the temperature of the cell according to the determined cell resistance.

10. The test system according to claim 9, characterized in that: The host computer is also used to restore the voltage value of the battery cell to a preset basic voltage value.

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