Micro-short circuit detection method, and electronic device and storage medium

Abstract

A micro-short circuit detection method, and an electronic device and a storage medium, which relate to the technical field of batteries. The method comprises: performing voltage adjustment by means of respectively charging or discharging a plurality of battery cells to be tested, such that respective voltages of the plurality of said battery cells are within a preset voltage range (S101); connecting the plurality of said battery cells, and detecting the current of each said battery cell to obtain a plurality of current results (S102); and for each said battery cell, determining a micro-short circuit situation of said battery cell on the basis of the current result corresponding to said battery cell, wherein the micro-short circuit situation comprises the presence of a micro-short circuit in said battery cell, or said battery cell is normal (S103). Therefore, the efficiency of micro-short circuit detection is improved.

Description

Micro short circuit detection methods, electronic devices and storage media

[0001] This application claims priority to Chinese Patent Application No. 2024116243844, filed on November 14, 2024, entitled “Micro Short Circuit Detection Method, Electronic Device and Storage Medium”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery technology, and in particular to a micro short-circuit detection method, electronic device, and storage medium. Background Technology

[0003] The battery cell is the energy storage component of a battery, and its performance directly determines the battery's performance. During battery manufacturing, it is typically necessary to detect micro-short circuits in the battery cells to ensure battery safety.

[0004] In related technologies, the K-value detection method is commonly used to measure the self-discharge performance of a battery cell, thereby determining whether a micro-short circuit exists in the cell. The K-value is the voltage drop of the cell per unit time. Specifically, the cell under test is allowed to rest for the first time, and the open circuit voltage (OVC) of the cell is measured at time T1. The cell is then allowed to rest for the second time, and the open circuit voltage is measured again at time T2. The K-value is the ratio of the difference between the two measured open circuit voltages to the time difference between time T2 and time T1. Based on the K-value, it can be determined whether a micro-short circuit exists in the cell.

[0005] However, when using the K-value detection method to determine the micro-short circuit condition of a battery cell, the process requires a long period of rest, which consumes a lot of time and results in low efficiency of micro-short circuit detection. Summary of the Invention

[0006] This application provides a micro short circuit detection method, electronic device, and storage medium to solve the problem that the efficiency of micro short circuit detection is low when judging the micro short circuit status of a battery cell by the K-value detection method, which requires a long period of rest and consumes a lot of time. This application aims to improve the detection efficiency.

[0007] Firstly, this application provides a method for detecting micro-short circuits, the method comprising:

[0008] By charging or discharging multiple cells under test separately, the voltage of each cell under test is adjusted so that its voltage is within a preset voltage range.

[0009] The plurality of cells to be tested are connected, and the current of each cell to be tested is detected to obtain multiple current results;

[0010] For each of the cells under test, the micro-short circuit condition of the cell under test is determined based on the current result corresponding to the cell under test. The micro-short circuit condition includes the presence of a micro-short circuit in the cell under test, or the cell under test being normal.

[0011] The method provided in the first aspect involves charging or discharging multiple cells under test (DUTs) separately to adjust their voltages, ensuring that each DUT's voltage falls within a preset range. This pre-processing of the DUTs before detecting micro-short circuits ensures uniformity in voltage and temperature, quickly eliminating or reducing the impact of differences in manufacturing processes, storage conditions, and material properties. By connecting the voltage-adjusted DUTs and detecting the current of each, multiple current results are obtained. For each DUT, the micro-short circuit condition is determined based on the corresponding current result, thus shortening the detection time, rapidly identifying micro-short circuit defects and differences, and improving detection efficiency.

[0012] In one possible design, the voltage regulation by charging or discharging multiple cells under test separately includes:

[0013] For each of the cells under test, the first open-circuit voltage of the cell under test is detected;

[0014] When the first open-circuit voltage is outside the preset voltage range, the difference between the first open-circuit voltage and the reference voltage is determined as the first adjustment voltage, where the reference voltage is a voltage value within the preset voltage range.

[0015] The battery cell under test is charged or discharged according to the first adjustment voltage and the first parameter, wherein the first parameter is a parameter used to evaluate the relationship between the capacity and voltage of the battery cell under test.

[0016] After a first duration, the second open-circuit voltage of the battery cell under test is detected. The first duration includes a second duration for charging or discharging the battery cell under test and a third duration for waiting for the battery cell under test to stabilize after charging or discharging.

[0017] When the second open-circuit voltage is within the preset voltage range, the voltage adjustment of the cell under test is completed;

[0018] When the second open-circuit voltage is outside the preset voltage range, a new first parameter is calculated based on the first open-circuit voltage, the second open-circuit voltage, and the amount of charge or discharge to the cell under test, and the difference between the second open-circuit voltage and the reference voltage is determined as the new first adjustment voltage.

[0019] Continue to charge or discharge the cell under test according to the new first parameter and the new first adjustment voltage until the second open circuit voltage of the cell under test is within the preset voltage range.

[0020] In one possible design, the plurality of cells under test are connected, and the current of each cell under test is detected to obtain multiple current results, including:

[0021] Connect the plurality of cells to be tested in parallel;

[0022] The current of each of the cells under test is detected, and multiple current results are obtained.

[0023] In one possible design, the plurality of cells under test are connected, and the current of each cell under test is detected to obtain multiple current results, including:

[0024] Obtain the third open-circuit voltage of each of the cells under test;

[0025] Based on the third open-circuit voltage, the cells under test are grouped to obtain multiple cell groups. The first voltage difference of the cell groups is less than the second voltage difference of the multiple cells under test before grouping. The first voltage difference is the difference between the open-circuit voltage of the cell under test with the largest third open-circuit voltage and the open-circuit voltage of the cell under test with the smallest third open-circuit voltage in the cell group. The second voltage difference is the difference between the open-circuit voltage of the cell under test with the largest third open-circuit voltage and the open-circuit voltage of the cell under test with the smallest third open-circuit voltage in the multiple cells under test before grouping.

[0026] Connect the cells under test in parallel in each cell group;

[0027] The current of each of the cells under test is detected, and multiple current results are obtained.

[0028] In one possible design, the method further includes, prior to voltage regulation of multiple cells under test:

[0029] The plurality of cells to be tested are buffered and left to stand still for a fourth time.

[0030] In one possible design, before detecting the current of each of the cells under test, the method further includes:

[0031] The multiple cells to be tested are buffered and left to stand still for a fifth time.

[0032] In one possible design, the fifth duration is less than or equal to 2 hours.

[0033] In one possible design, determining the micro-short circuit condition of the battery cell under test based on the current result of the cell under test includes:

[0034] When the absolute value of the current result is greater than a preset current range, it is determined that the cell under test has a micro-short circuit.

[0035] When the absolute value of the current result is within the preset current range, the cell under test is determined to be normal.

[0036] Secondly, this application provides a micro short-circuit detection device, which is a module for performing the micro short-circuit detection method in the first aspect and any possible design of the first aspect.

[0037] Thirdly, this application provides an electronic device including a memory and a processor, wherein the memory stores a computer-executable program or instructions, and the processor executes the computer-executable program or instructions to implement the micro short-circuit detection method as described in the first aspect and any possible design of the first aspect.

[0038] Fourthly, this application provides an electronic device including a processor that, when executing a computer-executable program or instructions in a memory, implements the micro-short-circuit detection method as described in the first aspect and any possible design of the first aspect.

[0039] Fifthly, this application provides a computer-readable storage medium storing a computer-executable program or instructions. When the computer-executable program or instructions are executed by a processor, they implement the micro-short circuit detection method provided in the first aspect of the embodiments of this application and any possible design of the first aspect.

[0040] In a sixth aspect, this application provides a computer program product comprising: execution instructions stored in a readable storage medium, at least one processor of an electronic device being able to read the execution instructions from the readable storage medium, and the at least one processor executing the execution instructions causing the electronic device to implement the first aspect and any possible design of the first aspect.

[0041] The above description is merely an overview of the technical solutions of the embodiments of this application. In order to better understand the technical means of the embodiments of this application and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of this application more obvious and understandable, specific implementation methods of this application are described below. Attached Figure Description

[0042] Figure 1 is a flowchart of a micro short-circuit detection method provided in an embodiment of this application.

[0043] Figure 2 is a flowchart of a voltage regulation method provided in an embodiment of this application.

[0044] Figure 3 is a flowchart of a voltage regulation method provided in an embodiment of this application.

[0045] Figure 4 is a flowchart of a current detection method provided in an embodiment of this application.

[0046] Figure 5 is a flowchart of a current detection method provided in an embodiment of this application.

[0047] Figure 6 is a flowchart of a micro short-circuit detection method provided in an embodiment of this application.

[0048] Figure 7 is a flowchart of a micro short-circuit detection method provided in an embodiment of this application.

[0049] Figure 8 is a flowchart of a micro short-circuit detection method provided in an embodiment of this application.

[0050] Figure 9 is a flowchart of a micro short-circuit detection method provided in an embodiment of this application.

[0051] Figure 10 is a schematic diagram of a micro short-circuit detection device provided in an embodiment of this application.

[0052] Figure 11 is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0053] Figure 12 is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0054] In this application, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c alone can mean: a alone, b alone, c alone, a combination of a and b, a combination of a and c, a combination of b and c, or a, b, and c, where a, b, and c can be single or multiple. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0055] The terms “center,” “longitudinal,” “lateral,” “up,” “down,” “left,” “right,” “front,” and “rear,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0056] The terms "connected" and "connected" should be interpreted broadly. For example, in circuit structures, "connected" or "connected" can refer not only to physical connections but also to electrical or signal connections. This could be a direct connection (physical connection) or an indirect connection via at least one intermediate component, as long as the circuit is connected. It could also refer to the internal connection between two components. Similarly, a signal connection can refer to a connection via a circuit or a medium, such as radio waves. Those skilled in the art will understand the specific meaning of these terms in this application based on the specific circumstances.

[0057] For example, this application provides a micro-short circuit detection method, apparatus, electronic device, storage medium, program, and chip. By preprocessing the battery cell under test before detecting its micro-short circuit condition, the voltage, temperature, and other properties of the battery cells under test are made consistent. This quickly eliminates the influence of differences between multiple battery cells under test caused by differences in manufacturing processes, storage conditions, material properties, etc., thereby shortening the time for detecting the micro-short circuit condition of the battery cell under test, quickly identifying micro-short circuit defects and differences in the battery cell under test, and improving detection efficiency.

[0058] The micro short-circuit detection method provided in this application can be executed by an electronic device or by a micro short-circuit detection device in an electronic device.

[0059] Among them, electronic devices can be servers, desktop computers, mobile phones, tablets, laptops, wearable devices, in-vehicle devices, augmented reality (AR) / virtual reality (VR) devices, etc.

[0060] The micro-short circuit detection device can be implemented through a combination of software and / or hardware. For example, the micro-short circuit detection device can be an application (APP), a webpage, or a public account. For the sake of simplicity, this application embodiment uses the implementation of a micro-short circuit detection device as an example.

[0061] The micro short-circuit detection method provided in the embodiments of this application will be described below with reference to Figure 1.

[0062] Please refer to Figure 1, which is a flowchart of a micro-short circuit detection method provided in an embodiment of this application. As shown in Figure 1, the method includes:

[0063] S101. By charging or discharging multiple cells under test separately, the voltage of each cell under test is adjusted so that the voltage of each cell under test is within a preset voltage range.

[0064] Among them, multiple cells under test can be cells produced in the same batch, and multiple cells under test have the same specifications.

[0065] For example, multiple cells under test can be cylindrical cells produced in the same batch, with a diameter of 18mm and a height of 65mm, a rated capacity of 2200mAh, and an operating voltage range of 2.8V to 4.2V. Here, 2.8V is the discharge cutoff voltage, and 4.2V is the charging cutoff voltage.

[0066] Because of differences in manufacturing processes, storage conditions, and material properties during the production of battery cells, even cells of the same specification can have voltage variations. These voltage differences can affect the timing of micro-short circuit detection. Therefore, before detecting micro-short circuits, the cell voltage can be pre-adjusted through charging or discharging to ensure consistency when entering the testing process.

[0067] The voltage of the battery cell under test is its open-circuit voltage. The micro-short-circuit detection device can determine a preset voltage range based on a preset voltage.

[0068] The preset voltage can take many forms.

[0069] The preset voltage is a voltage within the operating voltage range of the battery cell under test.

[0070] In some examples, the micro short-circuit detection device can determine the preset voltage based on the specifications of the battery cell under test.

[0071] For example, when the operating voltage range of the battery cell under test is 2.8V to 4.2V, the micro short-circuit detection device can set the preset voltage to 3.7V.

[0072] In other examples, the micro short-circuit detection device can acquire the voltage of each of the multiple cells under test separately and determine the average value of the voltages of the multiple cells under test as the preset voltage, or select the largest voltage among the voltages of the multiple cells under test and determine it as the preset voltage, or select the smallest voltage among the voltages of the multiple cells under test and determine it as the preset voltage.

[0073] In other examples, the micro short-circuit detection device can select one voltage as the preset voltage within a range of ±200mV of the average voltage of each of the multiple cells under test.

[0074] In some other examples, the micro short-circuit detection device can select one of the multiple cells under test as a reference cell, obtain the voltage of the reference cell, and determine the voltage of the reference cell as a preset voltage.

[0075] After determining the preset voltage, the micro short-circuit detection device can define the preset voltage range as the range of the preset voltage ± preset threshold.

[0076] For example, if the preset voltage is 3.7V and the preset threshold is 1μV, then the preset voltage range can be [3.7V-1μV, 3.7V+1μV].

[0077] Among them, the micro short-circuit detection device can adjust the voltage of multiple cells under test through various charging or discharging methods.

[0078] For example, a micro short-circuit detection device can discharge the battery cell under test with a voltage higher than the preset voltage using a capacitor, resistor, or inductor to reduce the voltage, and charge the battery cell under test with a voltage lower than the preset voltage using a capacitor, pulse, or series connection to increase the voltage, thereby adjusting the voltage of all battery cells under test to the preset voltage. This method can quickly adjust the voltage of the battery cells under test and ensure the consistency of multiple battery cells under test.

[0079] In addition to voltage regulation via charging or discharging, the micro short-circuit detection device can also connect multiple cells under test in parallel through a low-resistance parallel circuit to perform parallel voltage regulation.

[0080] S102. Connect multiple cells to be tested, detect the current of each cell to be tested, and obtain multiple current results.

[0081] Specifically, the micro short-circuit detection device can connect the positive and negative terminals of multiple cells under test respectively. For each cell under test, the micro short-circuit detection device can detect the current in the circuit where the cell under test is located through a current sensor to obtain the current result of the cell under test.

[0082] S103. For each cell under test, determine the micro-short circuit condition of the cell under test based on the current result corresponding to the cell under test.

[0083] Among them, micro-short circuit situations include the presence of a micro-short circuit in the cell under test, or the cell under test being normal.

[0084] For each battery cell under test, the micro-short circuit detection device can determine the micro-short circuit status of the battery cell by comparing the current result with the preset current range.

[0085] Specifically, when the absolute value of the current result is greater than the preset current range, the micro-short circuit detection device determines that there is a micro-short circuit in the cell under test.

[0086] When the absolute value of the current result is within the preset current range, the micro short-circuit detection device determines that the battery cell under test is normal.

[0087] The preset current range can be set according to the different batches of multiple cells under test and user needs, and this application does not limit it.

[0088] In this embodiment, the micro-short-circuit detection device regulates the voltage of multiple test cells by charging or discharging them separately, ensuring that the voltage of each cell is within a preset voltage range. This pre-processes the test cells before detecting micro-short circuits, ensuring consistency in voltage and temperature, quickly eliminating or reducing the impact of differences in manufacturing processes, storage conditions, and material properties. The device connects the voltage-regulated test cells and detects the current of each cell, obtaining multiple current results. Based on the corresponding current result for each cell, the micro-short-circuit condition is determined, thus shortening the detection time, quickly identifying micro-short-circuit defects and differences, and improving detection efficiency.

[0089] Based on the above exemplary description, in S101, the micro short-circuit detection device can adjust the voltage of multiple cells under test in various ways.

[0090] The voltage regulation method will now be explained with reference to Figures 2 and 3.

[0091] Please refer to Figure 2, which is a flowchart of a voltage regulation method provided in an embodiment of this application. As shown in Figure 2, the method includes:

[0092] S201. For each cell under test, detect the first open-circuit voltage of the cell under test.

[0093] The first open-circuit voltage refers to the voltage measured when the cell under test is not connected to any load before voltage regulation. The first open-circuit voltage can reflect the potential difference generated by the internal chemical reaction of the cell under test.

[0094] Due to various physical differences, the open-circuit voltage of the same type of battery cell under test may be different. Voltage regulation is to adjust the open-circuit voltage of the battery cell under test so that the open-circuit voltage of multiple battery cells under test is consistent.

[0095] Specifically, for each battery cell under test, the micro short-circuit detection device can measure the first open-circuit voltage of the battery cell by connecting voltage measuring devices such as multimeters and voltmeters to the battery cell under test.

[0096] S202. Determine whether the first open-circuit voltage is within the preset voltage range.

[0097] If the first open-circuit voltage is within the preset voltage range, the micro short-circuit detection device executes S207; if the first open-circuit voltage is outside the preset voltage range, the micro short-circuit detection device executes S203.

[0098] S203. The difference between the first open-circuit voltage and the reference voltage is determined as the first regulating voltage.

[0099] The reference voltage is a voltage value within a preset voltage range. The micro short-circuit detection device can select a voltage value within the preset voltage range as the reference voltage, that is, it can use the reference voltage as a standard to adjust the voltage of the battery cell under test, so that the voltage of the battery cell under test after voltage adjustment is within the preset voltage range.

[0100] The first adjustment voltage reflects the difference between the open-circuit voltage of the cell under test and the reference voltage. Based on this difference, the micro short-circuit detection device can determine the degree to which the voltage of the cell under test needs to be adjusted.

[0101] Specifically, when the first open-circuit voltage is greater than the reference voltage, the first regulating voltage is positive. When the first open-circuit voltage is less than the reference voltage, the first regulating voltage is negative.

[0102] When the first open-circuit voltage is greater than the reference voltage, it indicates that the micro-short-circuit detection device needs to reduce the open-circuit voltage of the cell under test, and the reduction value is the absolute value of the first adjustment voltage. When the first open-circuit voltage is less than the reference voltage, it indicates that the micro-short-circuit detection device needs to increase the open-circuit voltage of the cell under test, and the increase value is the absolute value of the first adjustment voltage.

[0103] In addition, the micro short-circuit detection device can also directly determine the absolute value of the difference between the first open-circuit voltage and the reference voltage as the first regulating voltage.

[0104] S204. Charge or discharge the battery cell under test according to the first regulating voltage and the first parameter.

[0105] The first parameter is used to evaluate the relationship between the capacity and voltage of the battery cell under test.

[0106] The first parameter can be the capacity-voltage ratio dQ / dV of the battery cell under test at the first open-circuit voltage. The capacity-voltage ratio dQ / dV represents the amount of electricity contained in the battery cell under test within a unit voltage range.

[0107] When initially adjusting the voltage of the cell under test, the first parameter can be a parameter preset according to the specifications of the cell under test. Alternatively, the micro short-circuit detection device can randomly select one cell under test from multiple cells under test, obtain the capacity-voltage ratio of that cell, and determine the capacity-voltage ratio of that cell as the first parameter.

[0108] Based on the first regulated voltage and the first parameter, the micro short-circuit detection device can determine the amount of charge or discharge required for the battery cell under test.

[0109] The micro short-circuit detection device can determine the amount of charge or discharge required for the battery cell under test using the following formula:

[0110] ΔQ1=ΔU1×dQ / dV1 (Formula 1)

[0111] Wherein, ΔQ1 is the amount of charge or discharge of the cell under test, ΔU1 is the first adjustment voltage, and dQ / dV1 is the capacity-voltage ratio of the cell under test under the first open-circuit voltage.

[0112] Among them, the micro short-circuit detection device can charge or discharge the battery cell under test through constant current, ramp, AC and other methods.

[0113] Based on this, the micro short-circuit detection device selects an appropriate charging or discharging method. When the first regulated voltage is greater than zero, the cell under test is discharged, and the discharge current is negative. When the first regulated voltage is less than zero, the cell under test is charged, and the charging current is positive.

[0114] S205. After the first duration, the second open-circuit voltage of the cell under test is detected.

[0115] The first duration includes a second duration for charging or discharging the battery cell under test, and a third duration for waiting for the battery cell under test to stabilize after charging or discharging.

[0116] The second duration is the time during which the micro short-circuit detection device charges or discharges the battery cell under test.

[0117] The micro short-circuit detection device can determine the second duration based on the amount of electricity charged or discharged by the battery cell under test.

[0118] The micro short-circuit detection device can determine the second duration using the following formula 2.

[0119] Where t1 is the second duration, and I1 is the charging current or discharging current of the battery cell under test.

[0120] Based on this, after a second period of time, the micro short-circuit detection device completes the charging or discharging of the battery cell under test, and the amount of charge or discharge reaches the required level.

[0121] After charging or discharging the battery cell under test, polarization will occur. If the second open-circuit voltage is measured immediately, the result may be inaccurate. Therefore, the micro-short-circuit detection device needs to wait a third time, until the battery cell under test stabilizes after charging or discharging, before measuring the second open-circuit voltage.

[0122] The first open-circuit voltage of the cell under test will change during charging or discharging. After charging or discharging is completed and a third time interval is waited, the micro short-circuit detection device detects the open-circuit voltage of the cell under test again to obtain the second open-circuit voltage. The detection method is similar to S201 and will not be described in detail here.

[0123] S206. Determine whether the second open-circuit voltage is within the preset voltage range.

[0124] If the second open-circuit voltage is within the preset voltage range, the micro short-circuit detection device executes S207; if the second open-circuit voltage is outside the preset voltage range, the micro short-circuit detection device executes S208.

[0125] S207. Complete the voltage adjustment of the battery cell under test.

[0126] If the second open-circuit voltage is within the preset voltage range, it indicates that the voltage state of the cell under test has met the requirements for voltage regulation, thus completing the voltage regulation of the cell under test.

[0127] S208. Based on the first open-circuit voltage, the second open-circuit voltage, and the amount of charge or discharge of the battery cell under test, calculate a new first parameter, and determine the difference between the second open-circuit voltage and the reference voltage as the new first adjustment voltage. Continue to charge or discharge the battery cell under test according to the new first adjustment voltage and the new first parameter, that is, continue to execute S204 until the second open-circuit voltage of the battery cell under test is within the preset voltage range.

[0128] If the second open-circuit voltage is outside the preset voltage range, the voltage of the cell under test needs to be adjusted again. Since the open-circuit voltage of the cell under test has changed, the micro short-circuit detection device can recalculate the new first parameter based on the first open-circuit voltage, the second open-circuit voltage, and the amount of charge or discharge of the cell under test. In the next voltage adjustment process, the new first parameter can be used to adjust the voltage.

[0129] The micro short-circuit detection device can determine the new first parameter using the following formula three.

[0130] Wherein, dQ / dV1 is the new first parameter, OCV1 is the first regulating voltage, and OCV2 is the second regulating voltage.

[0131] Based on this, the above operation is performed on each of the multiple cells under test, so that the voltage of each of the multiple cells under test is within the preset voltage range, and the multiple cells under test achieve consistency. This method can adjust each cell under test separately, and the adjustment accuracy is high, which helps to improve the accuracy of judging the micro short circuit of the cell under test.

[0132] Below, we introduce another voltage regulation method.

[0133] Please refer to Figure 3, which is a flowchart of a voltage regulation method provided in an embodiment of this application. As shown in Figure 3, the method includes:

[0134] S301 controls multiple cells under test to be connected in parallel sequentially.

[0135] Specifically, the micro short-circuit detection device can connect the positive terminals of multiple cells under test with wires and connect the negative terminals of multiple cells under test with wires, thereby connecting multiple cells under test in parallel in sequence.

[0136] When multiple cells under test are connected in parallel, their voltages can be automatically balanced.

[0137] S302. Buffer and hold multiple cells under test for a period of six hours to allow the voltage of each cell under test to be automatically balanced.

[0138] The sixth duration can be set based on experience.

[0139] By using parallel automatic balancing to regulate the voltage of multiple cells under test, consistency can be achieved without complex processing. The process is simple and the cost is low.

[0140] Based on the above exemplary description, in S102, the micro short-circuit detection device can detect the current of the cell under test in a variety of ways.

[0141] The method for detecting the current of the battery cell under test will be described below with reference to Figures 4 and 5.

[0142] Please refer to Figure 4, which is a flowchart of a current detection method provided in an embodiment of this application. As shown in Figure 4, the method includes:

[0143] S401. Connect multiple cells under test in parallel.

[0144] Specifically, the micro short-circuit detection device can connect the positive and negative terminals of multiple cells under test separately, thereby achieving parallel connection.

[0145] S402. The current of each cell under test is detected to obtain multiple current results.

[0146] For each battery cell under test, the micro short-circuit detection device can detect the current in the circuit where the battery cell is located through a current sensor to obtain the current result of the battery cell under test.

[0147] Below, we introduce another method for detecting the current of the battery cell under test.

[0148] Please refer to Figure 5, which is a flowchart of a current detection method provided in an embodiment of this application. As shown in Figure 5, the method includes:

[0149] S501. Obtain the third open-circuit voltage of each cell under test.

[0150] The third open-circuit voltage refers to the voltage measured when the cell under test is regulated and not connected to any load. The third open-circuit voltage can reflect the potential difference generated by the chemical reaction inside the cell.

[0151] Micro short-circuit detection devices can obtain the third open-circuit voltage in a variety of ways.

[0152] As a feasible approach, for each battery cell under test, the micro short-circuit detection device can measure the third open-circuit voltage of the battery cell by connecting voltage measuring devices such as multimeters and voltmeters to the battery cell under test.

[0153] As another feasible implementation, the micro short-circuit detection device can obtain the open-circuit voltage measured in the previous process of the battery cell under test. For example, during the voltage adjustment process of the battery cell under test, when the second open-circuit voltage is within the preset voltage range, the micro short-circuit detection device can determine the second open-circuit voltage as the third open-circuit voltage, so that the open-circuit voltage of the battery cell under test does not need to be measured again, thus further improving the detection efficiency.

[0154] S502. Based on the third open-circuit voltage, the cells under test are grouped to obtain multiple cell groups.

[0155] Among them, the first voltage difference of the cell group is less than the second voltage difference of the multiple cells under test before grouping.

[0156] The first voltage difference is the difference between the open-circuit voltage of the test cell with the largest third open-circuit voltage and the open-circuit voltage of the test cell with the smallest third open-circuit voltage in the cell group.

[0157] The second voltage difference is the difference between the open-circuit voltage of the battery cell with the largest third open-circuit voltage and the open-circuit voltage of the battery cell with the smallest third open-circuit voltage among the multiple battery cells under test before grouping.

[0158] Specifically, the micro short-circuit detection device can calculate the difference between the largest and smallest third open-circuit voltages among multiple cells under test, obtaining a second voltage difference. Based on the second voltage difference, the micro short-circuit detection device groups the multiple cells under test into multiple cell groups, such that the first voltage difference of each cell group is less than the second voltage difference.

[0159] Each cell group includes at least two cells to be tested.

[0160] Below, examples illustrate specific methods of grouping.

[0161] The number of cells to be tested is 10, namely cell A, cell B, cell C, cell D, cell E, cell F, cell G, cell H, cell I and cell J. The third open-circuit voltage of each cell to be tested is shown in Table 1 below.

[0162] Table 1

[0163] Among them, cell A has the largest third open-circuit voltage at 4.002V, while cell J has the smallest at 4.000V, with a first voltage difference of 2mV. Dividing the first voltage difference into 5 equal parts, and combining the largest and smallest third open-circuit voltages, we can obtain 5 voltage ranges: 4.000V~4.0004V, 4.0004V~4.0008V, 4.0008V~4.0012V, 4.0012V~4.0016V, and 4.0016V~4.002V.

[0164] Each cell under test is grouped according to its third open-circuit voltage and the voltage range mentioned above. The grouping results are shown in Table 2 below. Cells under test whose third open-circuit voltage is equal to the left or right end of the voltage range can be grouped into the previous or the next range.

[0165] Table 2

[0166] It is evident that the maximum voltage difference of the tested cells after grouping is less than the maximum voltage difference of the tested cells before grouping.

[0167] S503. Connect the cells to be tested in parallel in each cell group.

[0168] Specifically, for each cell group, the micro short-circuit detection device connects the positive terminals of each cell under test in the cell group to positive terminals and the negative terminals to negative terminals, thereby connecting the cells under test in parallel.

[0169] For example, based on Table 2 above, the micro short-circuit detection device connects cell B and cell H in parallel, cell C and cell I in parallel, cell G and cell J in parallel, and cell A, cell D, cell E and cell F in parallel.

[0170] Considering that a larger voltage difference between the cells under test makes it harder to identify currents affected by micro-short circuits, it's necessary to wait for the voltage difference to decrease before micro-short circuit detection can be performed. By grouping and then connecting them in parallel, the difference in open-circuit voltage between the cells under test in each cell group can be reduced, thereby reducing the difference in open-circuit voltage between the cells under test after parallel connection. When the micro-short circuit detection device detects current, the current affected by micro-short circuits can be more easily identified, thus improving both detection efficiency and accuracy.

[0171] S504. The current of each cell under test is detected to obtain multiple current results.

[0172] For each battery cell under test, the micro short-circuit detection device can detect the current in the circuit where the battery cell is located through a current sensor to obtain the current result of the battery cell under test.

[0173] Based on the above exemplary description, prior to S101, the micro short-circuit detection device can also perform buffering and static treatment on multiple cells under test.

[0174] Please refer to Figure 6, which is a flowchart of a micro-short circuit detection method provided in an embodiment of this application. As shown in Figure 6, before S101, the method includes:

[0175] Sa1, buffer and let multiple cells under test remain stationary for four hours.

[0176] Considering that the chemical substances in the battery cell and the environment in which the battery cell is located are not yet stable during the battery cell manufacturing process, multiple battery cells under test are buffered and allowed to stand still before voltage regulation. This allows the battery cells to reach a steady state, such as when the chemical substances, temperature, and voltage stabilize. This further shortens the time required for voltage regulation, enabling the micro short circuit detection device to quickly regulate the voltage of the battery cell under test to the preset voltage, thereby further improving the efficiency of micro short circuit detection.

[0177] Based on the above exemplary description, prior to S103, the micro short-circuit detection device can also perform buffering and static treatment on multiple cells under test.

[0178] Please refer to Figure 7, which is a flowchart of a micro-short circuit detection method provided in an embodiment of this application. As shown in Figure 7, before S103, the method includes:

[0179] Sa2, buffer and let multiple cells under test remain stationary for five hours.

[0180] Considering that the temperature and internal chemical state of the battery cell under test may change after voltage regulation, the micro short-circuit detection device can buffer multiple battery cells under test and allow them to reach a steady state before detecting the current of the battery cell under test. This allows the micro short-circuit detection device to obtain a more accurate current, which helps to improve the accuracy of micro short-circuit detection.

[0181] In some examples, the fifth duration is less than or equal to 2 hours.

[0182] After voltage regulation and before detecting the current of the cell under test, the micro short-circuit detection device buffers multiple cells under test for 0–60 minutes to allow them to reach a steady state. The specific buffering time can be determined based on the actual state of the cell under test.

[0183] Based on the embodiment in Figure 7, the micro short circuit detection device can simultaneously perform buffering and static treatment on multiple cells under test before S101 and before S103.

[0184] Please refer to Figure 8, which is a flowchart of a micro-short circuit detection method provided in an embodiment of this application. As shown in Figure 8, before S101, the method includes:

[0185] Sa3, buffer and let multiple cells under test remain stationary for four hours.

[0186] The description of Sa3 can be found in the description of Sa1 above, and will not be repeated here.

[0187] Based on the above exemplary description, in S103, the micro short circuit detection device can determine the micro short circuit condition of the cell under test by the method shown in Figure 9 below.

[0188] Prior to S103, the method includes:

[0189] Sa4, buffer and let multiple cells under test remain stationary for five hours.

[0190] The description of Sa4 can be found in the description of Sa2 above, and will not be repeated here.

[0191] In this embodiment, by allowing the cell under test to settle before voltage regulation, the cell reaches a stable state before voltage regulation, thus avoiding instability and minimizing the need for multiple voltage adjustments by the micro-short circuit detection device, thereby improving the efficiency of voltage regulation. A second settling of the voltage-regulated cell before current detection allows the micro-short circuit detection device to detect the current only after the cell has reached a steady state, resulting in more accurate current readings and improved precision in micro-short circuit detection.

[0192] Please refer to Figure 9, which is a flowchart of a micro-short circuit detection method provided in an embodiment of this application. As shown in Figure 9, S103 can be implemented by the following S103A to S103C:

[0193] S103A: Determine whether the absolute value of the current result is greater than the preset current range.

[0194] If the absolute value of the current result is greater than the preset current range, the micro short circuit detection device executes S103B; if the absolute value of the current result is within the preset current range, the micro short circuit detection device executes S103C.

[0195] S103B, It is determined that there is a micro short circuit in the cell under test.

[0196] S103C, The battery cell under test is confirmed to be normal.

[0197] In addition, if the absolute value of the current result is less than the preset current range, it indicates that the cell under test may have other problems other than micro short circuits. The micro short circuit detection device can provide a warning through alarms or other means.

[0198] Figure 10 is a schematic diagram of a micro short-circuit detection device according to an embodiment of this application. As shown in Figure 10, the device includes: an adjustment module 101, a detection module 102, and a determination module 103.

[0199] The adjustment module 101 is used to adjust the voltage of multiple cells under test by charging or discharging them separately, so that the voltage of each of the multiple cells under test is within a preset voltage range.

[0200] The detection module 102 is used to connect multiple cells to be tested, detect the current of each cell to be tested, and obtain multiple current results;

[0201] The determination module 103 is used to determine the micro-short circuit status of each cell under test based on the current result corresponding to the cell under test. The micro-short circuit status includes whether the cell under test has a micro-short circuit or whether the cell under test is normal.

[0202] It should be noted that the micro short-circuit detection device in this application embodiment can be used to execute the technical solution of the above method embodiment, and its implementation principle and technical effect are similar, so it will not be repeated here.

[0203] In some examples, the adjustment module 101 is specifically used to detect the first open-circuit voltage of each cell under test;

[0204] When the first open-circuit voltage is outside the preset voltage range, the difference between the first open-circuit voltage and the reference voltage is determined as the first regulating voltage, and the reference voltage is a voltage value within the preset voltage range;

[0205] Based on the first regulating voltage and the first parameter, the battery cell under test is charged or discharged. The first parameter is a parameter used to evaluate the relationship between the capacity and voltage of the battery cell under test.

[0206] After the first duration, the second open-circuit voltage of the battery cell under test is detected. The first duration includes a second duration for charging or discharging the battery cell under test and a third duration for waiting for the battery cell under test to stabilize after charging or discharging.

[0207] When the second open-circuit voltage is within the preset voltage range, the voltage regulation of the cell under test is completed;

[0208] When the second open-circuit voltage is outside the preset voltage range, a new first parameter is calculated based on the first open-circuit voltage, the second open-circuit voltage, and the amount of charge or discharge of the battery cell under test. The difference between the second open-circuit voltage and the reference voltage is determined as the new first adjustment voltage.

[0209] Continue charging or discharging the cell under test according to the new first parameter and the new first adjustment voltage until the second open circuit voltage of the cell under test is within the preset voltage range.

[0210] In some examples, the detection module 102 is specifically used to connect multiple cells under test in parallel;

[0211] The current of each cell under test is detected, and multiple current results are obtained.

[0212] In some examples, the detection module 102 is specifically used to obtain the third open-circuit voltage of each cell under test;

[0213] Based on the third open-circuit voltage, the cells under test are grouped to obtain multiple cell groups. The first voltage difference of the cell groups is less than the second voltage difference of the multiple cells under test before grouping. The first voltage difference is the difference between the open-circuit voltage of the cell under test with the largest third open-circuit voltage and the open-circuit voltage of the cell under test with the smallest third open-circuit voltage in the cell group. The second voltage difference is the difference between the open-circuit voltage of the cell under test with the largest third open-circuit voltage and the open-circuit voltage of the cell under test with the smallest third open-circuit voltage in the multiple cells under test before grouping.

[0214] Connect the cells under test in parallel in each cell group;

[0215] The current of each cell under test is detected, and multiple current results are obtained.

[0216] In some examples, the micro-short circuit detection device also includes a buffer quiescent module. The buffer quiescent module is used to buffer and quiescent multiple cells under test for a fourth duration.

[0217] In some examples, the cache rest module is also used to cache and rest multiple cells under test for a fifth duration.

[0218] In some examples, the fifth duration is less than or equal to 2 hours.

[0219] In some examples, module 103 is specifically used to determine that there is a micro-short circuit in the cell under test when the absolute value of the current result is greater than a preset current range;

[0220] If the absolute value of the current result is within the preset current range, the cell under test is determined to be normal.

[0221] Figure 11 is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. As shown in Figure 11, the electronic device may include a processor 201 and a memory 202. The memory 202 stores a computer program. When the processor 201 executes the computer program, it implements the micro short-circuit detection method shown in Figures 1 to 9 of this application embodiment.

[0222] Figure 12 is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. As shown in Figure 12, the electronic device may include a processor 301. When the processor 301 executes a computer-executable program or instruction in the memory to execute a computer program, it implements the micro short-circuit detection method shown in Figures 1 to 9 of this application embodiment.

[0223] The electronic device of this application can be used to execute the technical solutions of the method embodiments described above. Its implementation principle and technical effects are similar. The operations implemented by each module can be further referred to the relevant descriptions of the method embodiments, which will not be repeated here. The modules here can also be replaced by components or circuits.

[0224] Another embodiment of this application provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it can implement the micro short-circuit detection method shown in Figures 1 to 9 of this application.

[0225] Another embodiment of this application provides a computer program product, including: execution instructions, the execution instructions being stored in a readable storage medium, at least one processor of an electronic device being able to read the execution instructions from the readable storage medium, and at least one processor executing the execution instructions causing the electronic device to implement the micro short-circuit detection method shown in Figures 1 to 9 of this application embodiment.

[0226] Another embodiment of this application also provides a chip, which is connected to a memory, or the chip has a memory integrated on it. When the software program stored in the memory is executed, the micro short circuit detection method in the above method embodiment is implemented.

[0227] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed.

[0228] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this application is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., a solid-state disk (SSD)).

[0229] Those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination.

[0230] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A micro-short detection method, characterized by, The method includes: By charging or discharging multiple cells under test separately, the voltage of each cell under test is adjusted so that its voltage is within a preset voltage range. The plurality of cells to be tested are connected, and the current of each cell to be tested is detected to obtain multiple current results; For each of the cells under test, the micro-short circuit condition of the cell under test is determined based on the current result corresponding to the cell under test. The micro-short circuit condition includes the presence of a micro-short circuit in the cell under test, or the cell under test being normal.

2. The method of claim 1, wherein, The voltage adjustment by charging or discharging multiple cells under test separately includes: For each of the cells under test, the first open-circuit voltage of the cell under test is detected; When the first open-circuit voltage is outside the preset voltage range, the difference between the first open-circuit voltage and the reference voltage is determined as the first adjustment voltage, where the reference voltage is a voltage value within the preset voltage range. The battery cell under test is charged or discharged according to the first adjustment voltage and the first parameter, wherein the first parameter is a parameter used to evaluate the relationship between the capacity and voltage of the battery cell under test. After a first duration, the second open-circuit voltage of the battery cell under test is detected. The first duration includes a second duration for charging or discharging the battery cell under test and a third duration for waiting for the battery cell under test to stabilize after charging or discharging. When the second open-circuit voltage is within the preset voltage range, the voltage adjustment of the cell under test is completed; When the second open-circuit voltage is outside the preset voltage range, a new first parameter is calculated based on the first open-circuit voltage, the second open-circuit voltage, and the amount of charge or discharge to the cell under test, and the difference between the second open-circuit voltage and the reference voltage is determined as the new first adjustment voltage. Continue to charge or discharge the cell under test according to the new first parameter and the new first adjustment voltage until the second open circuit voltage of the cell under test is within the preset voltage range.

3. The method of claim 1, wherein, The process involves connecting the multiple cells under test, detecting the current of each cell under test, and obtaining multiple current results, including: Connect the plurality of cells to be tested in parallel; The current of each of the cells under test is detected, and multiple current results are obtained.

4. The method of claim 1, wherein, The process involves connecting the multiple cells under test, detecting the current of each cell under test, and obtaining multiple current results, including: Obtain the third open-circuit voltage of each of the cells under test; Based on the third open-circuit voltage, the cells under test are grouped to obtain multiple cell groups. The first voltage difference of the cell groups is less than the second voltage difference of the multiple cells under test before grouping. The first voltage difference is the difference between the open-circuit voltage of the cell under test with the largest third open-circuit voltage and the open-circuit voltage of the cell under test with the smallest third open-circuit voltage in the cell group. The second voltage difference is the difference between the open-circuit voltage of the cell under test with the largest third open-circuit voltage and the open-circuit voltage of the cell under test with the smallest third open-circuit voltage in the multiple cells under test before grouping. Connect the cells under test in parallel in each cell group; The current of each of the cells under test is detected, and multiple current results are obtained.

5. The method of claim 1, wherein, Before adjusting the voltage of multiple cells under test, the method further includes: The plurality of cells to be tested are buffered and left to stand still for a fourth time.

6. The method according to claim 1 or 5, characterized in that, Before detecting the current of each of the cells under test, the method further includes: The multiple cells to be tested are buffered and left to stand still for a fifth time.

7. The method of claim 6, wherein, The fifth duration is less than or equal to 2 hours.

8. The method according to any one of claims 1 to 4, characterized in that, The step of determining the micro-short circuit status of the battery cell under test based on the current result corresponding to the battery cell under test includes: When the absolute value of the current result is greater than a preset current range, it is determined that the cell under test has a micro-short circuit. When the absolute value of the current result is within the preset current range, the cell under test is determined to be normal.

9. An electronic device, comprising: include: At least one memory and at least one processor; The memory is used to store computer-executable programs or instructions; the processor is used to invoke the computer-executable programs or instructions in the memory, causing the electronic device to perform the method according to any one of claims 1-8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer-executable program or instructions configured to perform the method according to any one of claims 1-8.

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