WO2024077412A1 - Procédé de détection et dispositif de détection de court-circuit interne de batterie, et support de stockage - Google Patents

Procédé de détection et dispositif de détection de court-circuit interne de batterie, et support de stockage Download PDF

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Publication number
WO2024077412A1
WO2024077412A1 PCT/CN2022/124060 CN2022124060W WO2024077412A1 WO 2024077412 A1 WO2024077412 A1 WO 2024077412A1 CN 2022124060 W CN2022124060 W CN 2022124060W WO 2024077412 A1 WO2024077412 A1 WO 2024077412A1
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battery
voltage
short circuit
internal short
static
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PCT/CN2022/124060
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English (en)
Chinese (zh)
Inventor
李茂华
耿慧慧
张婷婷
李伟
吴凯
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宁德时代新能源科技股份有限公司
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Priority to PCT/CN2022/124060 priority Critical patent/WO2024077412A1/fr
Publication of WO2024077412A1 publication Critical patent/WO2024077412A1/fr

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]

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  • the present application relates to the field of batteries, and in particular to a method, a detection device and a storage medium for detecting a short circuit in a battery.
  • the embodiments of the present application provide a method, a detection device, and a storage medium for detecting a short circuit in a battery, which can effectively and timely detect instantaneous internal short circuit problems in the battery and improve the safety performance of the battery.
  • an embodiment of the present application provides a method for detecting a short circuit in a battery, comprising: obtaining a plurality of static voltages after charging of the battery is completed; determining whether a voltage jump exists in the battery based on the plurality of static voltages; and determining whether a momentary internal short circuit exists in the battery in the presence of the voltage jump.
  • the battery charging after the battery charging is completed, multiple static voltages of the battery are obtained.
  • the voltage jump refers to an abnormal voltage point in the static voltage-time data of the battery, where the static voltage drops significantly relative to the previous sampling moment and does not change the decreasing trend of the static voltage over time.
  • the instantaneous internal short circuit refers to the instantaneous short circuit of the positive and negative poles of the battery caused by a micro-defect of the battery. Therefore, by detecting and identifying the instantaneous internal short circuit of the battery, the defective battery can be detected as early as possible to avoid the consequences of more serious battery internal short circuit or battery thermal runaway, thereby improving the safety performance of the battery.
  • determining whether the battery has a voltage jump according to the multiple static voltages includes: obtaining a first voltage difference value obtained by subtracting the static voltage at the kth sampling point from the static voltage at the kth sampling point; wherein k is an integer greater than or equal to 1; and m is an integer greater than or equal to 1; and determining whether the battery has a voltage jump according to the multiple first voltage differences.
  • determining whether the battery has a voltage jump based on multiple first voltage difference values includes: performing a difference subtraction operation on two adjacent first voltage difference values to obtain multiple first difference subtraction values; and determining whether the battery has a voltage jump based on the multiple first difference subtraction values and a preset first threshold value.
  • the determining whether the battery has a voltage jump according to the multiple first subtraction values and the preset first threshold value includes: determining a target subtraction value less than the first threshold value from the multiple first subtraction values; determining whether the battery has an internal short circuit risk according to the target subtraction value; and determining whether the battery has a voltage jump according to the multiple first subtraction values and the multiple static voltages when the battery has the internal short circuit risk.
  • determining whether the battery has an internal short circuit risk according to the target difference subtraction value includes: determining that the battery has an internal short circuit risk when the number of consecutive target difference subtraction values is within a preset number range.
  • determining whether the battery has an internal short circuit risk according to the target difference subtraction value includes: determining that the battery has an internal short circuit risk when the time span of the continuous occurrence of the target difference subtraction value is less than a preset time threshold.
  • the method of determining whether the battery has a voltage jump according to the multiple first subtraction values and the multiple static voltages includes: when the first subtraction value at the nth sampling point is less than a preset first threshold, the static voltage at the n-1th sampling point is used to replace the static voltage at the nth sampling point to obtain multiple corrected static voltages; obtaining a second voltage difference value obtained by subtracting the corrected static voltage at the k+mth sampling point from the corrected static voltage at the kth sampling point; performing a subtraction operation on the two adjacent second voltage differences to obtain a second subtraction value; and determining that the battery has a voltage jump when the second subtraction value is less than a preset second threshold.
  • the abnormal voltage data caused by the voltage jump point can be effectively eliminated, misjudgment can be avoided, and the accuracy of the instantaneous internal short circuit of the battery can be improved.
  • the voltage jump point is caused by some accidental factors (such as circuit errors or external vibrations, etc.), which cause the voltage at a certain moment to be significantly higher or lower than the previous moment, but the subsequent voltage is normal.
  • the voltage jump point has nothing to do with the instantaneous internal short circuit of the battery and does not belong to the abnormal discharge of the battery caused by the internal short circuit of the battery.
  • performing a difference subtraction operation on two adjacent first voltage difference values to obtain multiple first difference subtraction values includes: determining a target difference subtraction value greater than zero among the multiple first voltage difference values; correcting the target difference subtraction value among the multiple first voltage difference values to zero to obtain multiple corrected voltage difference values; performing a difference subtraction operation on two adjacent corrected voltage difference values to obtain the multiple first difference subtraction values.
  • determining whether the battery has a voltage jump according to the multiple static voltages includes: performing voltage-time differential processing on the multiple static voltages, and determining whether the voltage jump exists according to the differential processing result.
  • an embodiment of the present application provides a battery internal short circuit detection device, comprising an acquisition module, a first determination module, and a second determination module.
  • the acquisition module is used to acquire multiple static voltages after the battery is charged;
  • the first determination module is used to determine whether the battery has a voltage jump according to the multiple static voltages;
  • the second determination module is used to determine whether the battery has an instantaneous internal short circuit when the voltage jump exists.
  • an embodiment of the present application provides a battery internal short circuit detection device, comprising a processor and a memory, wherein the memory is used to store data and computer programs, and the processor is used to call the data and computer programs in the memory to execute any of the above methods.
  • an embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon.
  • the computer program runs on a processor, the processor executes any of the above methods.
  • an embodiment of the present application provides a battery internal short circuit detection system, comprising a voltage acquisition module, a memory, and a processor.
  • the voltage acquisition module is used to obtain the static voltage of the battery;
  • the memory is used to store data and computer programs;
  • the processor is used to call the data and computer programs in the memory to execute any of the above methods.
  • an embodiment of the present application provides a short circuit detection system in a battery pack, comprising: a battery pack formed by a plurality of batteries, a voltage acquisition module coupled to each battery in the battery pack, a memory, and a processor.
  • the voltage acquisition module is used to obtain the static voltage of each battery in the battery pack;
  • the memory is used to store data and computer programs;
  • the processor is used to call the data and computer programs in the memory to execute any of the above methods.
  • an embodiment of the present application provides an electric vehicle, comprising the above-mentioned short circuit detection system within the battery pack.
  • an embodiment of the present application provides a computer program product, including a computer program, which implements any of the above methods when executed by a processor.
  • FIG1 is a schematic diagram showing the change of static voltage over time of a battery after high rate charging (lithium deposition test) provided in an embodiment of the present application;
  • FIG2 is a schematic diagram of a differential curve of the static voltage-time data of FIG1 ;
  • FIG3 is a schematic flow chart of a method for detecting a short circuit in a battery provided in an embodiment of the present application
  • FIG4 is a schematic diagram showing the change of the static voltage of a battery at different cycle times after full charge provided by an embodiment of the present application
  • FIG5 is an enlarged view of a local area in FIG4 ;
  • FIG6 is a schematic diagram of the static voltage variation over time provided by an embodiment of the present application.
  • FIG. 7 is a flow chart of the execution steps of the method for detecting a short circuit in a battery provided in an embodiment of the present application.
  • FIG8 is a schematic diagram of a first voltage difference value varying with time provided in an embodiment of the present application.
  • FIG9 is a flow chart of the execution steps of the method for detecting a short circuit in a battery provided in an embodiment of the present application.
  • FIG10 is a schematic diagram of a first subtraction value changing over time provided in an embodiment of the present application.
  • FIG11 is a flow chart of the execution steps of the method for detecting a short circuit in a battery provided in an embodiment of the present application.
  • FIG12 is a flow chart of the execution steps of the method for detecting a short circuit in a battery provided in an embodiment of the present application.
  • FIG13 is a schematic diagram of static voltage variation over time provided by an embodiment of the present application, showing a voltage jump point signal and a voltage jump signal respectively;
  • FIG14 is a schematic diagram of a first subtraction value changing over time provided in an embodiment of the present application.
  • FIG15 is a schematic diagram of the static voltage changing over time after voltage replacement provided in an embodiment of the present application.
  • FIG16 is a schematic diagram of a second subtraction value changing over time provided by an embodiment of the present application.
  • FIG17 is a flow chart of the execution steps of the method for detecting a short circuit in a battery provided in an embodiment of the present application.
  • FIG18 is a schematic diagram of the variation of the first subtraction value after correction over time provided in an embodiment of the present application.
  • FIG. 19 is a structural block diagram of a battery internal short circuit detection device provided in an embodiment of the present application.
  • FIG. 20 is a diagram showing the internal structure of a battery short circuit detection device provided in an embodiment of the present application.
  • Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields.
  • energy storage power systems such as hydropower, thermal power, wind power and solar power stations
  • electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields.
  • This method determines whether the battery has an internal short circuit based on the change in the static voltage after the battery cell is charged or discharged. Specifically, the method includes: obtaining the difference between the relaxation voltage difference of the battery cell at time k+1 and time k; after the battery is charged, when the difference is greater than 0, it is determined that the battery cell has no internal short circuit; when the difference is less than 0, it is determined that the battery cell has an internal short circuit; after the battery is discharged, when the difference is less than 0, it is determined that the battery cell has no internal short circuit, and when the difference is greater than 0, it is determined that the battery cell has an internal short circuit.
  • a short circuit in the battery may indeed cause abnormal voltage differential values at adjacent moments, but abnormal voltage differential values are not always caused by an internal short circuit.
  • the above technology may lead to a misjudgment of a short circuit in the battery in some cases.
  • Figure 1 is a schematic diagram of the static voltage after high-rate charging (lithium deposition test) of the battery provided in the embodiment of the present application
  • Figure 2 is a differential curve diagram of the static voltage-time data of Figure 1.
  • the internal short circuit of the battery includes two situations, namely, instantaneous internal short circuit and long-term internal short circuit.
  • the instantaneous internal short circuit often occurs for a few seconds or even shorter.
  • the battery discharges, and the short-circuit current quickly generates heat, which may cause the short-circuit point to burn or melt.
  • the occurrence of instantaneous internal short circuit means that the battery has a safety risk.
  • the long-term internal short circuit of the battery comes from the short circuit of the positive and negative electrodes caused by some factors (such as the positive active particles piercing the diaphragm), which may cause thermal runaway.
  • the long-term internal short circuit causes the battery to discharge continuously, and there is a large difference in the pressure difference between the internal short-circuited battery and the normal battery. Therefore, the pressure difference collected by the battery management system (Battery Management System, BMS) or the difference in the recorded balance situation can effectively detect the long-term internal short circuit of the battery.
  • BMS Battery Management System
  • the applicant has found that the instantaneous internal short circuit often occurs during the static process of the battery after charging, and the occurrence time is within 0 to 72 hours of the static time after the battery is charged. This is because after the battery is charged, the degree of lithium embedding in the anode is higher. If lithium precipitation exists, this is the most serious state of lithium precipitation. In addition, after the battery is charged, the pole piece expands greatly, the extrusion between the pole piece and the diaphragm is the most serious, and the risk of foreign objects piercing the diaphragm is higher.
  • the instantaneous internal short circuit comes from the instantaneous short circuit of the positive and negative poles of the battery, it may be affected by external vibrations and the like, and has a certain degree of randomness. Therefore, the time of occurrence has a certain randomness and may occur within 0 to 72 hours of static after charging.
  • the applicant has also found that the voltage jump caused by the instantaneous internal short circuit is small, usually 0.5mV to 1mV, and will not cause a significant change in the voltage difference. Due to the large number of battery cells in the battery assembly, the capacity, polarization degree and actual temperature of each battery cell are different. The voltage difference of the battery in the battery assembly is usually in the order of tens of millivolts, or even higher than 100mV. Therefore, the contribution of the instantaneous internal short circuit to the battery voltage difference can be ignored, which also means that the instantaneous internal short circuit may not be effectively detected by the battery voltage difference.
  • the applicant in order to detect and identify instantaneous internal short circuits, the applicant has found through in-depth research that the instantaneous internal short circuit time of the battery is short. From the trend of static voltage change over time, it is manifested as a voltage jump, rather than a gradual decrease in voltage over time. Based on this, the applicant proposes the following technical concept: identify instantaneous internal short circuits through the voltage jump characteristics during the static process of the battery after charging. When a transient internal short circuit is detected in the battery, an early warning process is performed.
  • some embodiments of the present application provide a method for detecting a short circuit in a battery, comprising the following steps:
  • step S1 since the internal short circuit of the battery is usually prone to occur in a high state of charge (State of Charge, SOC), the static voltage parameters can be collected after the battery is fully charged.
  • SOC state of Charge
  • the pole piece expands greatly, the diaphragm is under greater pressure, and it is more likely to pierce the diaphragm and cause an internal short circuit.
  • lithium deposition may exist in the battery, and the higher the SOC, the greater the amount of lithium deposition, so the internal short circuit caused by lithium deposition is more likely to occur.
  • the method for detecting an internal short circuit in a battery of an embodiment of the present application can be applied to electrical equipment, and the user can execute the method for detecting an internal short circuit in a battery before starting the electrical equipment to ensure that the electrical equipment is started under the condition of battery safety. This application does not limit this.
  • the static voltage refers to the difference between the positive electrode voltage and the negative electrode voltage when the battery is in a static state.
  • the static voltage of the battery can be collected according to a preset sampling period.
  • the sampling period of the static voltage can be 5 seconds to 120 seconds, for example, the sampling period can be 5 seconds, 10 seconds, 20 seconds, 30 seconds, 40 seconds, 50 seconds, 60 seconds, 80 seconds, 100 seconds or 120 seconds.
  • the sampling time can be 0 to 72 hours, for example, the sampling time can be 1 hour, 5 hours, 10 hours, 20 hours, 30 hours, 40 hours, 50 hours, 60 hours, 70 hours or 72 hours.
  • the sampling accuracy of the voltage is better than 0.1mV, for example, the sampling accuracy can be 0.01mV, 0.02mV, 0.03mV, 0.04mV, 0.05mV, 0.06mV, 0.07mV, 0.08mV, 0.09mV or 0.1mV. Since the instantaneous internal short circuit can occur at any time within 0 to 72 hours after the battery is charged, and the voltage jump amplitude caused by the instantaneous internal short circuit is usually 0.5 to 1mV, based on the above-mentioned settings of the sampling period, sampling duration and sampling accuracy, the embodiment of the present application is conducive to detecting the instantaneous internal short circuit of the battery within a reasonable time range, avoiding excessive detection time, and improving the convenience and efficiency of detection. In addition, the embodiment of the present application takes into account the voltage sampling accuracy to avoid missed detection, thereby realizing the early detection of batteries with micro-defects and improving the safety performance of the battery.
  • step S2 it can be understood that during the static process after the battery is fully charged, the static voltage of the battery tends to slowly decrease over time.
  • Figure 4 is a schematic diagram of the static voltage of the battery after full charge at different numbers of cycles over time
  • Figure 5 is an enlarged view of the local area in Figure 4
  • Figure 6 is a schematic diagram of the static voltage over time provided by the embodiment of the present application. It can be seen that Figures 4 to 6 all show that there is a voltage jump signal in the process of the static voltage decreasing over time. It is worth noting that the voltage jump refers to an abnormal voltage point in the static voltage-time data of the battery where the static voltage drops significantly and does not change the decreasing trend of the static voltage over time.
  • step S3 when there is a voltage jump signal in the static voltage-time data of the battery, it is determined that there is an instantaneous internal short circuit caused by an instantaneous short circuit between the positive and negative poles of the battery, which means that there are micro-defects in the battery and there is a risk of inducing a long-term internal short circuit.
  • multiple static voltages of the battery are obtained.
  • the battery has a momentary internal short circuit. Therefore, by detecting and identifying the momentary internal short circuit of the battery, defective batteries can be detected as early as possible to avoid causing more serious consequences of battery internal short circuit or battery thermal runaway, thereby improving the safety performance of the battery.
  • the presence of a voltage jump signal can be determined from multiple static voltages according to the change trend of the static voltage of the battery over time. In other embodiments, the presence of a voltage jump signal can be determined from multiple static voltages according to an algorithm.
  • the following describes several algorithms for determining whether a battery has a voltage jump based on multiple static voltages.
  • step S2 determining whether a battery has a voltage jump according to a plurality of static voltages includes the following steps:
  • S701 Obtain a first voltage difference value obtained by subtracting the static voltage at the kth sampling point from the static voltage at the k+mth sampling point; wherein k is an integer greater than or equal to 1; and m is an integer greater than or equal to 1;
  • S702 Determine whether there is a voltage jump in the battery according to a plurality of first voltage differences.
  • FIG8 is a schematic diagram of multiple first voltage difference values calculated by the embodiment of the present application changing over time. It can be understood that since the static voltage of the battery decreases slowly over time, the first voltage difference value is theoretically less than or equal to 0. However, in reality, due to errors in the detection data, the calculated multiple first voltage difference values will fluctuate around 0.
  • the first voltage difference corresponding to point A shown in FIG8 is significantly lower than the first voltage difference at other sampling moments, based on which it can be determined that there is a voltage jump.
  • the preset threshold is -0.0005V.
  • the preset threshold range can be set according to actual conditions, for example, it can be set to -0.0003 to -0.0008V, such as -0.0003V, -0.0004V, -0.0005V, -0.0006V, -0.0007V or -0.0008V, etc., and this application does not limit this.
  • the static voltage of the kth sampling point and the static voltage of the k+1th sampling point are obtained, and the static voltage of the k+1th sampling point is calculated to subtract the static voltage of the kth sampling point to obtain a first voltage difference, that is, the static voltage difference of each two adjacent sampling points is calculated respectively, thereby obtaining multiple first voltage differences.
  • a first voltage difference that is, the static voltage difference of each two adjacent sampling points is calculated respectively, thereby obtaining multiple first voltage differences.
  • the static voltage of the kth sampling point and the static voltage of the k+mth sampling point are obtained, and the static voltage of the k+mth sampling point is calculated to subtract the static voltage of the kth sampling point to obtain the first voltage difference, that is, the static voltage difference of each two sampling points at fixed intervals is calculated respectively, so as to obtain multiple first voltage differences.
  • the voltage jump amplitude caused by the instantaneous internal short circuit is small, by calculating the first voltage difference of each two sampling points at fixed intervals, the amplitude of the first voltage difference is more obvious, thereby improving the recognition accuracy.
  • step 702 determining whether there is a voltage jump in the battery according to a plurality of first voltage differences includes the steps of:
  • S901 performing a subtraction operation on two adjacent first voltage difference values to obtain a plurality of first subtraction values
  • S902 Determine whether there is a voltage jump in the battery according to a plurality of first subtraction values and a preset first threshold.
  • the preset first threshold value can be -0.0005V to -0.0008V, such as -0.0003V, -0.0004V, -0.0005V, -0.0006V, -0.0007V or -0.0008V.
  • the preset first threshold value of 0.0005V As an example, when there is a first difference value less than -0.0005V, such as point B, it is determined that there is a voltage jump, and it is determined that the battery has an instantaneous internal short circuit. It can be seen that by performing a difference subtraction operation on the first voltage differences between two adjacent ones, the characteristics of the voltage abnormal point can be made more prominent, which is conducive to identifying whether the battery has a voltage jump and improving the detection accuracy of the instantaneous internal short circuit of the battery.
  • step S902 determining whether there is a voltage jump in the battery according to a plurality of first subtraction values and a preset first threshold value includes the following steps:
  • S1101 Determine a target subtraction value that is less than a first threshold from a plurality of first subtraction values
  • S1102 Determine whether the battery has an internal short circuit risk according to the target difference impairment value
  • S1103 When there is a risk of internal short circuit in the battery, determine whether there is a voltage jump in the battery according to a plurality of first subtraction values and a plurality of static voltages.
  • the battery when the number of consecutive target difference subtractions is within a preset number range, it is determined that the battery has an internal short circuit risk. For example, if there is a target difference subtraction, and the number of sampling points corresponding to the target difference subtraction is 1 to 3, for example, 1, 2 or 3, it is determined that the battery has an internal short circuit risk, and further the instantaneous internal short circuit is identified based on the voltage jump signal. If the number of sampling points corresponding to the target difference subtraction exceeds the preset number range, it is determined that the internal short circuit risk is eliminated, that is, the voltage jump signal is caused by lithium back-insertion caused by lithium precipitation, rather than the battery having an instantaneous internal short circuit.
  • the battery when the time span of the continuous occurrence of the target difference impairment is less than the preset time threshold, it is determined that the battery has an internal short circuit risk. For example, if there is a target difference impairment, and the time span of the continuous occurrence of the target difference impairment is less than 60s, it is determined that the battery has an internal short circuit risk, and the instantaneous internal short circuit is further identified according to the voltage jump signal. If the time span of the continuous occurrence of the target difference impairment is greater than 60s, it is determined that the internal short circuit risk is removed, that is, the voltage jump signal is caused by the lithium back insertion caused by lithium precipitation, rather than the battery having an instantaneous internal short circuit.
  • the time span of the continuous occurrence of the target difference impairment refers to: for the continuous occurrence of the target difference impairment, the time span between the sampling time corresponding to the first target difference impairment and the sampling time corresponding to the last target difference impairment.
  • the above-mentioned preset time threshold can be 30s to 90s, such as 30s, 40s, 50s, 60s, 70s, 80s, 90s, etc., and this application is not limited to this.
  • a target difference value less than a first threshold value is first determined from multiple first difference values, and then, based on whether the number of consecutive target difference values is within a preset number range, or based on whether the time span of consecutive target difference values is less than a preset time threshold, the voltage jump signal caused by the instantaneous internal short circuit can be effectively distinguished from the lithium reinsertion voltage signal caused by lithium plating and reinsertion, thereby avoiding misjudgment and improving the detection accuracy of the battery internal short circuit.
  • step S902 determining whether there is a voltage jump in the battery according to a plurality of first subtraction values and a plurality of static voltages includes the steps of:
  • S1202 Obtain a second voltage difference value obtained by subtracting the corrected static voltage at the kth sampling point from the corrected static voltage at the k+mth sampling point;
  • FIG. 13 is a schematic diagram of the static voltage variation over time provided by an embodiment of the present application, showing a voltage jump signal (point C) and a voltage jump point signal (i.e., point D and point E), respectively.
  • the voltage jump characterizes whether an instantaneous internal short circuit occurs in the battery, which reflects the change in the internal state of the battery.
  • the voltage jump does not change the downward trend of the static voltage, that is, the voltage change trend over time of the sampling points before and after the corresponding sampling point of the voltage jump is the same.
  • the voltage jump point is a circuit error, which originates from the limitations of the measuring instrument, experimental conditions, measurement methods and human factors. Therefore, the voltage jump point appears to be random, and in the voltage sampling data, the voltage change trend over time of the sampling points before and after the corresponding sampling point of the voltage jump point is opposite.
  • FIG14 is a schematic diagram of the first subtraction value changing over time provided by an embodiment of the present application, wherein the three abnormal points shown in the figure correspond to the voltage jump signal and the voltage jump point signal of FIG13 . It can be seen that both the voltage jump and the voltage jump point will cause the first subtraction value to be significantly lower and may be lower than the first threshold. Therefore, in the data processing process, the voltage jump point signal needs to be eliminated to effectively distinguish the voltage jump signal and the voltage jump point signal and avoid misjudgment caused by circuit errors.
  • the time point at which the first subtraction value is lower than the first threshold value (eg, -0.0005V) may be recorded, and the voltage at the corresponding time point may be replaced by the voltage at the previous adjacent time point for further processing.
  • FIG15 shows a schematic diagram of the static voltage changing with time after voltage replacement provided by an embodiment of the present application, wherein the voltage replacement point is indicated by an arrow.
  • the second voltage difference obtained by subtracting the corrected static voltage of the kth sampling point from the corrected static voltage of the kth sampling point is re-obtained; then the second voltage difference values adjacent to each other are subtracted again to obtain the second difference value, and the data schematic diagram of the second difference value changing with time shown in FIG16 is obtained.
  • the threshold value -0.0005V
  • the static voltage of the n-1 sampling point is used to replace the static voltage of the n sampling point to obtain multiple corrected static voltages; further, the voltage difference operation is re-performed on the multiple corrected static voltages to obtain multiple second voltage differences, and the difference subtraction operation is re-performed on the multiple second voltage differences to obtain multiple second difference subtraction values, and finally, according to whether there is a second difference subtraction value less than a preset second threshold value, it is determined whether there is a voltage jump. Based on this, the abnormal voltage data caused by the voltage jump point can be effectively eliminated, the misjudgment caused by the circuit error can be avoided, and the detection accuracy of the internal short circuit of the battery can be improved.
  • step S901 performing a subtraction operation on two adjacent first voltage difference values to obtain a plurality of first subtraction values includes the following steps:
  • S1701 Determine a target difference subtraction value greater than zero among a plurality of first voltage difference values
  • FIG18 shows a schematic diagram of the first subtraction value after correction provided by the embodiment of the present application over time.
  • the first voltage difference is often superimposed with noise, and noise reduction processing is required.
  • the first voltage difference is greater than 0, it is assigned to zero, otherwise the original value is retained.
  • the reason for this treatment is: first, after the battery is charged, the static voltage is a continuous reduction process. In theory, the first voltage difference cannot be greater than zero. If it is greater than zero, it comes from the influence of various types of noise. Therefore, it is reasonable to assign it to zero, and the noise of the first voltage difference is reduced.
  • the subtraction result of the first voltage difference is also superimposed with noise, which is not conducive to the identification of the instantaneous internal short circuit of the battery.
  • the influence of data noise can be eliminated and the detection and recognition accuracy can be improved.
  • determining whether a battery has a voltage jump based on a plurality of static voltages includes: performing voltage-time differential processing on the plurality of static voltages, and determining whether a voltage jump exists based on the differential processing result.
  • the method for detecting short circuits in batteries processes the static voltage-time data of the battery through a specific algorithm, thereby determining whether the battery has an instantaneous internal short circuit and improving the safety performance of the battery.
  • the embodiments of the present application can effectively distinguish between voltage jump signals, voltage jump point signals, and lithium reinsertion voltage signals caused by lithium precipitation; the algorithm is simple, and only simple subtraction, assignment, replacement, and comparison are performed, so the running speed is fast and the hardware requirements are low.
  • the embodiments of the present application also provide a data noise reduction function to eliminate data noise such as subtraction operations, which is conducive to improving the recognition accuracy of abnormal data.
  • the embodiment of the present application further provides a battery internal short circuit detection device, including an acquisition module, a first determination module and a second determination module, wherein:
  • the acquisition module is used to acquire multiple static voltages after battery charging is completed
  • the first determination module is used to determine whether there is a voltage jump in the battery according to a plurality of static voltages
  • the second determination module is used to determine whether a transient internal short circuit exists in the battery when there is a voltage jump.
  • the first determination module is further used to: obtain a first voltage difference value obtained by subtracting the static voltage of the kth sampling point from the static voltage of the kth sampling point, and determine whether the battery has a voltage jump according to the multiple first voltage differences, wherein k is an integer greater than or equal to 1; and m is an integer greater than or equal to 1.
  • the first determination module is further used to: perform a subtraction operation on two adjacent first voltage difference values to obtain multiple first subtraction values; and determine whether the battery has a voltage jump according to the multiple first subtraction values and a preset first threshold.
  • the first determination module is further used to: determine a target difference value that is less than a first threshold value from multiple first difference values; determine whether the battery has an internal short circuit risk based on the target difference value; and when the battery has an internal short circuit risk, determine whether the battery has a voltage jump based on multiple first difference values and multiple static voltages.
  • the first determination module is further used to: determine that the battery has an internal short circuit risk when the number of consecutive target difference subtraction values is within a preset number range.
  • the first determination module is further used to: determine that the battery has an internal short circuit risk when a time span of consecutive occurrences of target difference reduction values is less than a preset time threshold.
  • the first determination module is further used for: when the first subtraction value of the nth sampling point is less than a preset first threshold, replacing the static voltage of the nth sampling point with the static voltage of the n-1th sampling point to obtain multiple corrected static voltages; obtaining a second voltage difference value obtained by subtracting the corrected static voltage of the k+mth sampling point from the corrected static voltage of the kth sampling point; performing a subtraction operation on two adjacent second voltage differences to obtain a second subtraction value; and determining that the battery has a voltage jump when the second subtraction value is less than a preset second threshold.
  • the first determination module is also used to: determine a target difference subtraction value greater than zero among multiple first voltage difference values; correct the target difference subtraction value among the multiple first voltage difference values to zero to obtain multiple corrected voltage difference values; and perform subtraction operations on two adjacent corrected voltage difference values to obtain multiple first difference subtraction values.
  • the first determination module is further used to: perform voltage-time differential processing on a plurality of static voltages, and determine whether a voltage jump exists according to the differential processing result.
  • Each module in the above detection device can be implemented in whole or in part by software, hardware and a combination thereof.
  • Each module can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute the operations corresponding to each module above.
  • the present application embodiment also provides a detection device for a short circuit in a battery, which can be a terminal, and its internal structure diagram can be shown in Figure 20.
  • the detection device includes a processor, a memory, an input/output interface, a communication interface, a display unit and an input device.
  • the processor, the memory and the input/output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input/output interface.
  • the processor of the detection device is used to provide computing and control capabilities.
  • the memory of the detection device includes a non-volatile storage medium and an internal memory.
  • the non-volatile storage medium stores an operating system and a computer program.
  • the internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium.
  • the input/output interface of the detection device is used to exchange information between the processor and an external device.
  • the communication interface of the detection device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies.
  • the embodiment of the present application also provides a computer-readable storage medium on which a computer program is stored.
  • the processor executes each step of the method for detecting a short circuit in a battery in the embodiment of the present application.
  • the embodiment of the present application also provides a battery internal short circuit detection system, which includes: a voltage acquisition module, a memory and a processor.
  • the voltage acquisition module is used to obtain the static voltage of the battery;
  • the memory is used to store data and computer programs;
  • the processor is used to call the data and computer programs in the memory to execute the various steps of the battery internal short circuit detection method of the embodiment of the present application.
  • the embodiment of the present application also provides a detection system for a short circuit in a battery pack, which includes: a battery pack formed by multiple batteries, a voltage acquisition module coupled to each battery in the battery pack, a memory, and a processor; wherein the voltage acquisition module is used to obtain the static voltage of each battery in the battery pack; the memory is used to store data and computer programs; the processor is used to call the data and computer programs in the memory to execute the various steps in the detection method for a short circuit in a battery pack of the embodiment of the present application.
  • a detection system for a short circuit in a battery pack which includes: a battery pack formed by multiple batteries, a voltage acquisition module coupled to each battery in the battery pack, a memory, and a processor; wherein the voltage acquisition module is used to obtain the static voltage of each battery in the battery pack; the memory is used to store data and computer programs; the processor is used to call the data and computer programs in the memory to execute the various steps in the detection method for a short circuit in a battery pack of the embodiment of the present application
  • the embodiment of the present application also provides an electric vehicle, including the above-mentioned battery pack internal short circuit detection system.
  • the electric vehicle of this embodiment can perform a self-check of the vehicle health status, and when it is determined that the battery pack has a momentary internal short circuit, an early warning is issued.
  • the electric vehicle includes a vehicle body and a battery pack internal short circuit detection system, and the vehicle body is provided with a accommodating space for accommodating the battery pack internal short circuit detection system.
  • the electric vehicle can be a pure electric vehicle, or a hybrid vehicle or an extended-range vehicle.
  • a drive motor is provided in the vehicle body, the drive motor is electrically connected to the battery pack, and the battery pack provides electrical energy.
  • the drive motor is connected to the wheels on the vehicle body through a transmission mechanism, thereby driving the vehicle to move.
  • An embodiment of the present application also provides a computer program product, including a computer program, which implements each step of the method for detecting a short circuit in a battery when the computer program is executed by a processor.
  • Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc.
  • Volatile memory may include random access memory (RAM) or external cache memory.
  • RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Protection Of Static Devices (AREA)
  • Charge And Discharge Circuits For Batteries Or The Like (AREA)
  • Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)

Abstract

La présente demande concerne un procédé et un dispositif de détection d'un court-circuit interne d'une batterie, et un support de stockage. Le procédé de détection consiste à : acquérir de multiples tensions de repos après que la batterie a fini de charger ; déterminer, en fonction des multiples tensions de repos, si un saut de tension se produit dans la batterie ; et si le saut de tension se produit, déterminer que la batterie est en court-circuit interne transitoire.
PCT/CN2022/124060 2022-10-09 2022-10-09 Procédé de détection et dispositif de détection de court-circuit interne de batterie, et support de stockage WO2024077412A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/CN2022/124060 WO2024077412A1 (fr) 2022-10-09 2022-10-09 Procédé de détection et dispositif de détection de court-circuit interne de batterie, et support de stockage

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2022/124060 WO2024077412A1 (fr) 2022-10-09 2022-10-09 Procédé de détection et dispositif de détection de court-circuit interne de batterie, et support de stockage

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Citations (7)

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Publication number Priority date Publication date Assignee Title
CN101689684A (zh) * 2007-06-11 2010-03-31 松下电器产业株式会社 电池的内部短路探知装置和方法以及电池组件
CN108323186A (zh) * 2017-08-25 2018-07-24 深圳市云中飞网络科技有限公司 终端设备及其电池安全监控方法和监控系统
CN108323221A (zh) * 2017-08-25 2018-07-24 深圳市云中飞网络科技有限公司 终端设备、电池组件和电池保护板
WO2019157613A1 (fr) * 2018-02-13 2019-08-22 广东欧珀移动通信有限公司 Dispositif terminal et système et procédé de surveillance d'anomalie de batterie associés
CN111624508A (zh) * 2019-02-27 2020-09-04 东莞新能德科技有限公司 电池的短路检测方法和装置
CN113093018A (zh) * 2021-03-09 2021-07-09 北京交通大学 一种锂离子电池瞬时内短路检测装置和方法
CN113253120A (zh) * 2021-06-29 2021-08-13 蜂巢能源科技有限公司 电池突发型内短路诊断方法、装置、存储介质及电子设备

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101689684A (zh) * 2007-06-11 2010-03-31 松下电器产业株式会社 电池的内部短路探知装置和方法以及电池组件
CN108323186A (zh) * 2017-08-25 2018-07-24 深圳市云中飞网络科技有限公司 终端设备及其电池安全监控方法和监控系统
CN108323221A (zh) * 2017-08-25 2018-07-24 深圳市云中飞网络科技有限公司 终端设备、电池组件和电池保护板
WO2019157613A1 (fr) * 2018-02-13 2019-08-22 广东欧珀移动通信有限公司 Dispositif terminal et système et procédé de surveillance d'anomalie de batterie associés
CN111624508A (zh) * 2019-02-27 2020-09-04 东莞新能德科技有限公司 电池的短路检测方法和装置
CN113093018A (zh) * 2021-03-09 2021-07-09 北京交通大学 一种锂离子电池瞬时内短路检测装置和方法
CN113253120A (zh) * 2021-06-29 2021-08-13 蜂巢能源科技有限公司 电池突发型内短路诊断方法、装置、存储介质及电子设备

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