A lithium battery charging and discharging function detection management method, device and storage medium

Abstract

The present application relates to a lithium battery charge and discharge function detection management method, device and storage medium, belonging to the field of energy detection, and the method includes: obtaining the number of cycles of the lithium battery, and obtaining the remaining cycle life of the lithium battery based on the number of cycles and preset factory information; obtaining the charging efficiency of the lithium battery and the service life of the lithium battery; obtaining the life grade of the lithium battery based on the charging efficiency and the service life; obtaining the life range corresponding to the life grade based on a preset life grade database; judging whether the remaining cycle life falls within the life range; if the remaining cycle life falls within the life range, judging that the lithium battery charge and discharge function is normal; if the remaining cycle life does not fall within the life range, judging that the lithium battery charge and discharge function is abnormal. The present application has the effect of being conducive to accurately evaluating the charge and discharge function of the lithium battery.

Description

Technical Field

[0001] The present application relates to the field of energy monitoring, and in particular to a lithium battery charging and discharging function detection and management method, device and storage medium. Background Art

[0002] Lithium batteries refer to batteries that use lithium metal or lithium alloy as positive and negative electrode materials and non-aqueous electrolyte solutions. They are currently widely used in various mobile electronic devices or new energy vehicles, ships and other fields.

[0003] When lithium batteries are used in new energy vehicles or new energy ships and other fields, the battery performance will decrease as the lithium battery is used for a longer time. However, the degradation of battery performance cannot be directly measured. Therefore, it is necessary to estimate the life of the lithium battery in advance and evaluate the charge and discharge performance of the lithium battery based on the life of the lithium battery. This will facilitate a decision on whether to replace the battery to ensure the safe operation of new energy vehicles or new energy ships and avoid unnecessary accidents.

[0004] The existing method for estimating the life of lithium batteries is based on the cycle life of lithium batteries. The cycle life refers to the number of cycles of complete charge and discharge of lithium batteries, and the cycle life is usually marked at the factory. As the number of cycles of complete charge and discharge of lithium batteries increases, the cycle life of lithium batteries will also decrease accordingly. However, due to the complex internal chemical reactions of lithium batteries and their susceptibility to external factors such as impact or high temperature, the existing evaluation of the life of lithium batteries based on the cycle life of lithium batteries is often inaccurate, which in turn easily leads to inaccurate results in evaluating the charge and discharge performance of lithium batteries based on the life of lithium batteries.

[0005] Application Contents

[0006] In order to facilitate accurate evaluation of the charging and discharging function of a lithium battery, the present application provides a lithium battery charging and discharging function detection and management method, device and storage medium.

[0007] In the first aspect, the present application provides a lithium battery charge and discharge function detection and management method using the following technical solutions:

[0008] A lithium battery charge and discharge function detection and management method, comprising:

[0009] Obtaining the number of cycles of the lithium battery, and obtaining the remaining cycle life of the lithium battery based on the number of cycles and preset factory information;

[0010] Get the charging efficiency and usage time of lithium batteries;

[0011] Obtaining a lifespan grade of the lithium battery based on the charging efficiency and the usage time;

[0012] Obtaining a life range corresponding to a life grade based on a preset life grade database;

[0013] Determining whether the remaining cycle life falls within the life range;

[0014] If the remaining cycle life falls within the life range, it is determined that the charging and discharging functions of the lithium battery are normal;

[0015] If the remaining cycle life does not fall within the life range, it is determined that the charging and discharging functions of the lithium battery are abnormal.

[0016] By adopting the above technical scheme, after obtaining the remaining cycle life of the lithium battery, the life grade of the lithium battery is further obtained based on the charging efficiency and the usage time of the lithium battery, and then the charging and discharging function of the lithium battery is judged based on whether the remaining cycle life falls within the life grade. That is, there is no need to judge the charging and discharging function of the lithium battery only by the cycle life. The life of the lithium battery can be further estimated by the charging efficiency and usage time of the lithium battery, which is conducive to improving the accuracy of the battery life estimation, and then is conducive to accurately evaluating the charging and discharging function of the lithium battery.

[0017] Optionally, obtaining the number of cycles of the lithium battery and obtaining the remaining cycle life of the lithium battery based on the number of cycles and preset factory information includes:

[0018] Get the number of times the lithium battery is fully charged and fully discharged;

[0019] Based on the number of full charges and the number of full discharges, a cycle number is obtained;

[0020] Based on the preset factory information of the lithium battery, obtain the number of cycle life of the lithium battery;

[0021] The remaining cycle life is obtained by subtracting the number of cycles from the number of cycle life.

[0022] By adopting the above technical solution, the remaining cycle life is an estimated value of the life of the lithium battery without the influence of external factors. Calculating the remaining cycle life facilitates the subsequent further estimation of the life of the lithium battery based on external factors.

[0023] Optionally, obtaining the charging efficiency of the lithium battery includes:

[0024] Obtaining the charging capacity and charging time of the lithium battery at every preset time period;

[0025] After the lithium battery is charged, the discharge amount of the lithium battery when it is discharged to a preset termination voltage and the discharge time when the lithium battery is discharged to the preset termination voltage are obtained;

[0026] Substituting the charge amount, the charge time, the discharge amount and the discharge time into a preset charge efficiency formula to obtain a charge efficiency;

[0027] The charging efficiency formula is as follows:

[0028] Y=(m×t1) / (n×t2)*100%;

[0029] Among them, Y is the charging efficiency, m is the discharge amount, t1 is the discharge time, n is the charge amount, and t2 is the charging time.

[0030] By adopting the above technical solution, by calculating the charging efficiency of the lithium battery at every preset time period, it is helpful to intuitively see the efficiency change of the lithium battery during the charging and discharging process.

[0031] Optionally, obtain the usage time of the lithium battery, including:

[0032] Based on the factory information, obtaining the factory time of the lithium battery;

[0033] Get the current time;

[0034] The absolute value of the time difference between the current time and the factory time is calculated to obtain the usage time of the lithium battery.

[0035] By adopting the above technical solution, the usage time of the lithium battery is the current time minus the factory time. By calculating the usage time of the lithium battery, it is beneficial to further estimate the life of the lithium battery based on the usage time and charging efficiency, thereby improving the accuracy of the battery life estimation, and further facilitating the accurate evaluation of the charging and discharging function of the lithium battery.

[0036] Optionally, the lifespan level includes a first lifespan level, a second lifespan level and a third lifespan level; the first lifespan level is greater than the second lifespan level, and the second lifespan level is greater than the third lifespan level;

[0037] The obtaining of the life grade of the lithium battery based on the charging efficiency and the usage time includes:

[0038] Determining whether the charging efficiency is lower than a preset efficiency threshold;

[0039] If the charging efficiency is not lower than the efficiency threshold, determining that the life level of the remaining cycle life is the first level;

[0040] If the charging efficiency is lower than the efficiency threshold, determining whether the usage time of the lithium battery is greater than a preset time threshold;

[0041] If the usage time of the lithium battery is not greater than the time threshold, determining that the life level of the remaining cycle life is the second level;

[0042] If the usage time of the lithium battery is greater than the time threshold, it is determined that the life level of the remaining cycle life is the third level.

[0043] By adopting the above technical solution, the remaining cycle life is divided into different life levels based on charging efficiency and usage time, which is beneficial to improving the accuracy of lithium battery life assessment, and further conducive to accurately assessing the charging and discharging function of the lithium battery based on the life level of the lithium battery.

[0044] Optionally, after the lithium battery is charged, obtaining the discharge amount of the lithium battery when it is discharged to a preset termination voltage and the discharge time of the lithium battery when it is discharged to the preset termination voltage, the method further comprises:

[0045] Obtain the working voltage of the lithium battery corresponding to each discharge moment in real time;

[0046] Generate a visual discharge curve based on the discharge time and the corresponding working voltage;

[0047] Calculating the first-order derivative of the visualized discharge curve and generating a visualized derivative curve;

[0048] Obtaining the inflection point of the visualized derivative curve based on a preset inflection point detection algorithm;

[0049] Determining whether the lithium battery fails based on the inflection point;

[0050] If a fault occurs, an alarm message will be issued;

[0051] If no fault occurs, a step of obtaining the life grade of the lithium battery based on the charging efficiency and the usage time is performed.

[0052] By adopting the above technical solution, when the lithium battery is discharging, a visual discharge curve is generated based on the discharge time and the operating voltage, and a visual derivative curve is obtained based on the visual discharge curve. The visual derivative curve is used to display the slope change of the visual discharge curve. It is determined whether the lithium battery has a fault based on the inflection point of the visual derivative curve, and whether to estimate the life of the lithium battery based on whether a fault has occurred. This is conducive to making a comprehensive judgment on the situation during the charging and discharging process of the lithium battery in the process of estimating the life of the lithium battery.

[0053] Optionally, judging whether the lithium battery fails based on the inflection point includes:

[0054] Determining whether the inflection point changes the upward direction of the visualized derivative curve;

[0055] If the inflection point changes the upward direction of the visualized derivative curve, obtaining the inflection point derivative corresponding to the inflection point;

[0056] Determining whether the inflection point derivative is greater than a preset derivative threshold;

[0057] If the inflection point derivative is greater than the derivative threshold, obtaining the battery temperature of the lithium battery;

[0058] Determining whether the battery temperature is greater than a preset temperature threshold;

[0059] If the battery temperature is greater than the temperature threshold, it is determined that the lithium battery fails.

[0060] By adopting the above technical solution, whether a lithium battery fails is judged based on the inflection point and the battery temperature of the lithium battery, thereby effectively improving the accuracy of judging whether a lithium battery fails.

[0061] In a second aspect, a terminal device provided by the present application adopts the following technical solution:

[0062] A terminal device includes a memory, a processor, and a computer program stored in the memory and capable of running on the processor. When the processor loads and executes the computer program, the above-mentioned lithium battery charging and discharging function detection and management method is adopted.

[0063] By adopting the above technical solution, the above lithium battery charge and discharge function detection and management method is generated into a computer program and stored in a memory so as to be loaded and executed by a processor, thereby making a terminal device based on the memory and the processor for easy use.

[0064] In a third aspect, the present application provides a computer-readable storage medium that adopts the following technical solution:

[0065] A computer-readable storage medium stores a computer program, and when the computer program is loaded and executed by a processor, the above-mentioned lithium battery charge and discharge function detection and management method is adopted.

[0066] By adopting the above technical solution, the above lithium battery charge and discharge function detection and management method is generated into a computer program and stored in a computer-readable storage medium so as to be loaded and executed by a processor. The computer-readable storage medium facilitates the reading and storage of the computer program.

[0067] In summary, the present application has at least one of the following beneficial technical effects:

[0068] 1. After obtaining the remaining cycle life of the lithium battery, the life grade of the lithium battery is further obtained based on the charging efficiency and the use time of the lithium battery. Then, the charge and discharge function of the lithium battery is judged based on whether the remaining cycle life falls within the life grade. That is, there is no need to judge the charge and discharge function of the lithium battery only by the cycle life. The life of the lithium battery can be further estimated by the charging efficiency and use time of the lithium battery, which is conducive to improving the accuracy of the battery life estimation, and then to accurately evaluate the charge and discharge function of the lithium battery.

[0069] 2. Classifying the remaining cycle life into different life levels based on charging efficiency and usage time is conducive to improving the accuracy of lithium battery life assessment, and further conducive to accurately assessing the charging and discharging functions of lithium batteries based on the life levels of lithium batteries.

[0070] 3. When the lithium battery is discharged, a visual discharge curve is generated based on the discharge time and the operating voltage, and a visual derivative curve is obtained based on the visual discharge curve. The visual derivative curve is used to display the slope change of the visual discharge curve. Whether the lithium battery has a fault is determined based on the inflection point of the visual derivative curve, and whether the life of the lithium battery is estimated based on whether a fault has occurred. This is conducive to making a comprehensive judgment on the situation during the charging and discharging process of the lithium battery in the process of estimating the life of the lithium battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 It is a flow chart of one implementation method of a lithium battery charge and discharge function detection and management method according to an embodiment of the present application.

[0072] Figure 2 It is a flow chart of one implementation method of a lithium battery charge and discharge function detection and management method according to an embodiment of the present application.

[0073] Figure 3 It is a flow chart of one implementation method of a lithium battery charge and discharge function detection and management method according to an embodiment of the present application.

[0074] Figure 4 It is a flow chart of one implementation method of a lithium battery charge and discharge function detection and management method according to an embodiment of the present application.

[0075] Figure 5 It is a flow chart of one implementation method of a lithium battery charge and discharge function detection and management method according to an embodiment of the present application.

[0076] Figure 6 It is a flow chart of one implementation method of a lithium battery charge and discharge function detection and management method according to an embodiment of the present application.

[0077] Figure 7It is a flow chart of one implementation method of a lithium battery charge and discharge function detection and management method according to an embodiment of the present application. DETAILED DESCRIPTION

[0078] The following is combined with Figures 1 to 7 This application is described in further detail.

[0079] The embodiment of the present application discloses a method for detecting and managing the charging and discharging functions of a lithium battery.

[0080] Reference Figure 1 A lithium battery charge and discharge function detection and management method comprises the following steps:

[0081] S101. Obtain the number of cycles of the lithium battery, and obtain the remaining cycle life of the lithium battery based on the number of cycles and preset factory information.

[0082] The number of cycles refers to the number of times a lithium battery has actually cycled from the time it left the factory to the current time. The number of times a lithium battery is fully charged and fully discharged is considered a cycle of the lithium battery. The factory information includes the factory date of the lithium battery and the cycle life preset when the lithium battery leaves the factory. The remaining cycle life of the lithium battery is based on the number of cycles of the lithium battery and the cycle life of the lithium battery. The cycle life of a lithium battery refers to the number of charge and discharge cycles that a lithium battery can withstand before the battery capacity decays to the preset specified value.

[0083] S102: Obtain the charging efficiency of the lithium battery and the usage time of the lithium battery.

[0084] The charging efficiency of a lithium battery refers to the ratio of the capacity released when the lithium battery is discharged to a preset cut-off voltage under certain discharge conditions to the input battery capacity. That is, the charging efficiency of a lithium battery can be calculated by the discharge capacity of the lithium battery under fixed discharge conditions and the charge capacity of the lithium battery.

[0085] The service life of a lithium battery can be calculated based on the lithium battery's factory date and the current date.

[0086] S103: Obtain the life level of the lithium battery based on the charging efficiency and the usage time.

[0087] In a specific implementation, the charging efficiency and usage time of a lithium battery can both reflect the charging and discharging functions of the lithium battery. In this embodiment, after obtaining the charging efficiency and usage time of the lithium battery, the life level of the lithium battery is obtained based on the charging efficiency and usage time, so as to make a more accurate estimate of the life of the lithium battery. The life level is divided into three levels, namely the first life level, the second life level and the third life level. The first life level is greater than the second life level, and the second life level is greater than the third life level.

[0088] When the life level of the lithium battery is the first life level, it indicates that the current cycle life of the lithium battery is the longest. When the life level of the lithium battery is the third life level, it indicates that the current cycle life of the lithium battery is the shortest. When the life level of the lithium battery is the second life level, it indicates that the current cycle life of the lithium battery is between the first life level and the second life level.

[0089] S104. Obtain a life range corresponding to the life grade based on a preset life grade database.

[0090] The life level database stores life levels and life ranges corresponding to life levels, and the life range is the range of the cycle life of lithium batteries. For example, the life level obtained based on charging efficiency and usage time is the first life level, and the life range corresponding to the first life level in the life level database is 400 to 500 times, then the life range obtained by the current execution subject is 400 to 500 times.

[0091] S105: Determine whether the remaining cycle life falls within the life range.

[0092] S106: If the remaining cycle life falls within the life range, it is determined that the charging and discharging functions of the lithium battery are normal.

[0093] If the remaining cycle life falls within the life range, it indicates that the lithium battery is less affected by external factors, and the charging and discharging functions of the lithium battery can be determined to be normal. For example, if the remaining cycle life of the lithium battery is 420 times, the life level of the lithium battery obtained based on the charging efficiency and the usage time is the first life level, and the life range corresponding to the first life level is 400 to 500 times. Since 420 times falls within the life range, the charging and discharging functions of the lithium battery are determined to be normal.

[0094] S107: If the remaining cycle life does not fall within the life range, it is determined that the charging and discharging functions of the lithium battery are abnormal.

[0095] If the remaining cycle life does not fall within the life range, it indicates that the lithium battery is greatly affected by external factors, and the charging and discharging function of the lithium battery can be determined to be abnormal. For example, if the remaining cycle life of the lithium battery is 320 times, the life level of the lithium battery obtained based on the charging efficiency and the length of use is the first life level, and the life range corresponding to the first life level is 400 to 500 times. Since 320 times does not fall within the life range, the charging and discharging function of the lithium battery is determined to be abnormal.

[0096] The implementation principle of this embodiment is: after obtaining the remaining cycle life of the lithium battery, the life grade of the lithium battery is further obtained based on the charging efficiency and the usage time of the lithium battery, and then the charging and discharging function of the lithium battery is judged based on whether the remaining cycle life falls within the life grade. That is, there is no need to judge the charging and discharging function of the lithium battery based solely on the cycle life. The life of the lithium battery can be further estimated by the charging efficiency and usage time of the lithium battery, which is conducive to improving the accuracy of the battery life estimation, and further conducive to accurately evaluating the charging and discharging function of the lithium battery.

[0097] exist Figure 1 In step S101 of the embodiment shown, the remaining cycle life of the lithium battery is the cycle life of the lithium battery when it leaves the factory minus the actual number of cycles of the lithium battery. Figure 2 The illustrated embodiment is described in detail.

[0098] Reference Figure 2 , obtaining the number of cycles of the lithium battery, and obtaining the remaining cycle life of the lithium battery based on the number of cycles and preset factory information includes the following steps:

[0099] S201. Obtain the number of times a lithium battery is fully charged and the number of times a lithium battery is fully discharged.

[0100] A full charge of a lithium battery refers to the process in which the lithium battery completes a 100% full charge. Similarly, a full discharge of a lithium battery refers to the process in which the lithium battery completes a 100% full discharge.

[0101] S202: Obtain the number of cycles based on the number of full charges and the number of full discharges.

[0102] An example of the number of cycles of a lithium battery is given based on the number of full charges and discharges of the lithium battery. If the initial power of the lithium battery is 100%, the power of the lithium battery after the first discharge is 40%, and then the lithium battery is charged to 100%, the second time the lithium battery is discharged to 60% and then charged to 100%, these two charges and discharges are regarded as one cycle of the lithium battery.

[0103] S203: Based on the preset factory information of the lithium battery, obtain the number of cycle life of the lithium battery.

[0104] The factory information of lithium batteries includes the number of cycle life of lithium batteries. The number of cycle life refers to the number of cycle life estimated by the lithium battery when it leaves the factory.

[0105] S204, subtract the number of cycles from the number of cycle life to obtain the remaining cycle life.

[0106] The remaining cycle life is the number of cycle life minus the number of cycles. For example, based on the factory information of the lithium battery, the cycle life of the lithium battery is 500 times, and the number of cycles of the lithium battery is 320 times, then the remaining cycle life is 500=320=180 times.

[0107] The implementation principle of this embodiment is: the remaining cycle life is an estimated value of the life of the lithium battery without the influence of external factors. The calculation of the remaining cycle life facilitates the subsequent further estimation of the life of the lithium battery based on external factors.

[0108] exist Figure 1 In step S102 of the illustrated embodiment, the charging efficiency of the lithium battery is calculated based on the charging amount and the discharging amount of the lithium battery. Figure 3 The illustrated embodiment is described in detail.

[0109] Reference Figure 3 , obtaining the charging efficiency of the lithium battery includes the following steps:

[0110] S301. Obtain the charging capacity and charging time of the lithium battery at every preset time period.

[0111] The charge capacity refers to the charging current of the lithium battery.

[0112] S302: After the lithium battery is charged, obtain the discharge amount of the lithium battery when it is discharged to a preset termination voltage and the discharge time of the lithium battery when it is discharged to the preset termination voltage.

[0113] Discharge capacity refers to the discharge current of the lithium battery.

[0114] In this embodiment, the charge and discharge amounts of the lithium battery are measured based on the Hall effect sensor, and the Hall effect sensor can be used to measure the current flowing into and out of the battery.

[0115] S303, substituting the charging capacity, charging time, discharging capacity and discharging time into a preset charging efficiency formula to obtain the charging efficiency.

[0116] The charging efficiency formula is as follows:

[0117] Y=(m×t1) / (n×t2)*100%;

[0118] Among them, Y is the charging efficiency, m is the discharge amount, t1 is the discharge time, n is the charge amount, and t2 is the charging time.

[0119] For example, if the charging capacity n of a lithium battery is 500 mA, the charging time t2 is 2 hours, the discharging capacity m is 400 mA, and the discharging time t1 is 2 hours, then the charging efficiency Y=(400×2) / (500×2)*100%=80%.

[0120] It should be noted that the preset time period is greater than or equal to the sum of the charging time of the lithium battery and the discharging time of the lithium battery. In addition, the initial voltage of the lithium battery during charging should be equal to the termination voltage to ensure the accuracy of the charging efficiency calculation.

[0121] The implementation principle of this embodiment is: by calculating the charging efficiency of the lithium battery at every preset time period, it is helpful to intuitively see the efficiency change of the lithium battery during the charging and discharging process.

[0122] exist Figure 1 In step S102 of the illustrated embodiment, the usage time of the lithium battery is calculated based on the factory time of the lithium battery and the current time. Figure 4 The illustrated embodiment is described in detail.

[0123] Reference Figure 4 , obtaining the usage time of lithium battery includes the following steps:

[0124] S401. Obtain the production time of the lithium battery based on the production information.

[0125] As can be seen from step S101, the factory information includes the factory date of the lithium battery and the cycle life preset when the lithium battery leaves the factory, so the factory time of the lithium battery can be obtained through the factory information.

[0126] S402: Get current time.

[0127] S403: Calculate the absolute value of the time difference between the current time and the factory time to obtain the usage time of the lithium battery.

[0128] The service life of the lithium battery is the absolute value of the difference between the current time and the factory time. Specifically, the factory time and the current time are both dates.

[0129] The implementation principle of this embodiment is: the usage time of the lithium battery is the current time minus the factory time. By calculating the usage time of the lithium battery, it is beneficial to further estimate the life of the lithium battery based on the usage time and charging efficiency, thereby improving the accuracy of the battery life estimation, and further facilitating the accurate evaluation of the charging and discharging function of the lithium battery.

[0130] exist Figure 1 In step S103 of the illustrated embodiment, the life grade of the lithium battery is obtained based on the charging efficiency and the usage time, and the life of the lithium battery can be further estimated according to the life grade. Figure 5 The illustrated embodiment is described in detail.

[0131] Reference Figure 5, the lifespan level includes a first lifespan level, a second lifespan level and a third lifespan level; the first lifespan level is greater than the second lifespan level, and the second lifespan level is greater than the third lifespan level;

[0132] The life level of lithium batteries is obtained based on charging efficiency and usage time, including the following steps:

[0133] S501: Determine whether the charging efficiency is lower than a preset efficiency threshold.

[0134] S502: If the charging efficiency is not lower than the efficiency threshold, determine that the remaining cycle life is at the first level.

[0135] It can be seen from step S103 that when the life level of the lithium battery is the first life level, it indicates that the current cycle life of the lithium battery is the longest; when the life level of the lithium battery is the third life level, it indicates that the current cycle life of the lithium battery is the shortest; when the life level of the lithium battery is the second life level, it indicates that the current cycle life of the lithium battery is between the first life level and the second life level.

[0136] Taking steps S501 to S502 as an example, if the efficiency threshold is set to 75% and the charging efficiency of the lithium battery is 85%, since the charging efficiency is greater than the efficiency threshold, the current execution subject determines that the life level of the remaining cycle life is the first level.

[0137] S503: If the charging efficiency is lower than the efficiency threshold, determine whether the usage time of the lithium battery is greater than a preset time threshold.

[0138] If the charging efficiency is lower than the efficiency threshold, it indicates that the charging efficiency of the lithium battery is low. At this time, the use time of the lithium battery is further judged to obtain the life grade of the lithium battery.

[0139] S504: If the usage time of the lithium battery is not greater than the time threshold, determine that the life level of the remaining cycle life is the second level.

[0140] S505: If the usage time of the lithium battery is greater than the time threshold, determine that the life level of the remaining cycle life is the third level.

[0141] Based on step S501 to step S502, an example is given for step S503 to step S505. If the charging efficiency of the lithium battery is 65%, the charging efficiency is less than the efficiency threshold at this time, and the current execution subject determines whether the usage time of the lithium battery is greater than the preset time threshold;

[0142] If the duration threshold is set to 5 years, the usage time of the lithium battery is 3 years. Since 3 years is less than 5 years and the charging efficiency is less than the efficiency threshold, the current execution entity determines that the remaining cycle life is at the second level.

[0143] If the lithium battery is used for 6 years, which is greater than the time threshold, the current execution entity determines that the remaining cycle life is at the third level.

[0144] The implementation principle of this embodiment is: the remaining cycle life is divided into different life levels based on charging efficiency and usage time, which is conducive to improving the accuracy of lithium battery life assessment, and further conducive to accurately assessing the charging and discharging function of the lithium battery based on the life level of the lithium battery.

[0145] exist Figure 3 After step S302 of the illustrated embodiment, it is first determined whether the lithium battery has a fault, and then the charging efficiency of the lithium battery is calculated. Figure 6 The illustrated embodiment is described in detail.

[0146] Reference Figure 6 After the lithium battery is charged, obtaining the discharge amount of the lithium battery when it is discharged to a preset termination voltage and the discharge time of the lithium battery when it is discharged to the preset termination voltage includes the following steps:

[0147] S601. Acquire the operating voltage of the lithium battery corresponding to each discharging moment in real time.

[0148] The operating voltage of a lithium battery can be measured based on a voltmeter or an ADC circuit.

[0149] S602: Generate a visualized discharge curve based on the discharge time and the corresponding working voltage.

[0150] In this embodiment, the X-axis of the visualized discharge curve is the discharge time, and the Y-axis is the working voltage. The visual discharge curve can be obtained by recording and plotting the working voltage at each discharge time obtained in real time.

[0151] S603 : Calculate the first-order derivative of the visualized discharge curve and generate a visualized derivative curve.

[0152] The first-order derivative of the visualized discharge curve is the slope of the visualized discharge curve, so the visualized derivative curve is the slope change of the visualized discharge curve.

[0153] S604: Obtain an inflection point of the visualized derivative curve based on a preset inflection point detection algorithm.

[0154] The inflection point refers to a point where the curve changes its upward or downward direction. In this embodiment, the inflection point detection algorithm is used to detect the inflection point of the visualized derivative curve. Specifically, firstly, an image of the visualized derivative curve is obtained, and in the image matrix of the image of the visualized derivative curve, the values ​​in the matrix are traversed based on the window function. If a certain value changes significantly, it is determined to be at the inflection point. Since the inflection point detection algorithm based on image monitoring has been widely used, it will not be repeated here.

[0155] S605: Determine whether the lithium battery fails based on the inflection point.

[0156] If an inflection point appears in the visualized derivative curve, it indicates that the slope value of the visualized discharge curve has changed. The change may be that the slope becomes larger or smaller, and whether the lithium battery has a fault can be determined based on the change in the slope.

[0157] S606: If a fault occurs, an alarm message is issued.

[0158] If a lithium battery fails, the current execution entity will issue an alarm message to prompt the management personnel to maintain the lithium battery.

[0159] S607: If no fault occurs, execute the step of obtaining the life level of the lithium battery based on the charging efficiency and the usage time.

[0160] It should be noted that if you want to judge whether a lithium battery fails based on the inflection point, you need to maintain a high hourly rate for the lithium battery. The hourly rate of a lithium battery refers to the discharge rate expressed in discharge time, which is used to indicate the number of hours required for the battery to discharge to the termination voltage at a current of a preset intensity. That is, the lower the hourly rate, the greater the power consumption. At this time, the inflection point may appear at the initial moment, that is, the visualized discharge curve may have no inflection point, so it is necessary to ensure a high hourly rate in order to calculate whether the lithium battery fails based on the inflection point.

[0161] The implementation principle of this embodiment is: when the lithium battery is discharged, a visual discharge curve is generated based on the discharge time and the operating voltage, and a visual derivative curve is obtained based on the visual discharge curve. The visual derivative curve is used to display the slope change of the visual discharge curve. Whether the lithium battery fails is determined based on the inflection point of the visual derivative curve, and whether the life of the lithium battery is estimated based on whether a failure occurs. This is conducive to making a comprehensive judgment on the situation during the charging and discharging process of the lithium battery in the process of estimating the life of the lithium battery.

[0162] exist Figure 6 In step S605 of the illustrated embodiment, the inflection point refers to the point where the slope of the visualized discharge curve changes, and the change in the slope can be determined by the inflection point, thereby determining whether the lithium battery has a fault. Figure 7 The illustrated embodiment is described in detail.

[0163] Reference Figure 7 , judging whether a lithium battery failure occurs based on the inflection point includes the following steps:

[0164] S701 , determining whether the inflection point changes the upward direction of the visualized derivative curve.

[0165] If the inflection point changes the upward direction of the visualized derivative curve, that is, the initial trend of the visualized derivative curve is upward, after passing the inflection point, the trend of the visualized derivative curve is downward, that is, the slope of the visualized discharge curve suddenly changes.

[0166] S702: If the inflection point changes the upward direction of the visualized derivative curve, obtain the inflection point derivative corresponding to the inflection point.

[0167] In this embodiment, the slope is used to indicate the capacity change of the lithium battery. If the slope decreases, it indicates that the capacity loss of the lithium battery increases.

[0168] If the inflection point changes the downward direction of the visualized derivative curve, no action is taken.

[0169] S703: Determine whether the inflection point derivative is greater than a preset derivative threshold.

[0170] S704: If the inflection point derivative is greater than the derivative threshold, obtain the battery temperature of the lithium battery.

[0171] If the inflection point derivative is greater than the derivative threshold, it indicates that the slope of the lithium battery decreases, that is, the capacity loss of the lithium battery increases. At this time, whether the lithium battery fails is further judged based on the battery temperature of the lithium battery.

[0172] If the inflection point derivative is less than the derivative threshold, no action is taken.

[0173] S705: Determine whether the battery temperature is greater than a preset temperature threshold.

[0174] In this embodiment, the battery temperature of the lithium battery is measured by a temperature sensor.

[0175] S706: If the battery temperature is greater than the temperature threshold, determine that the lithium battery is faulty.

[0176] If the battery temperature is greater than the temperature threshold and the inflection point derivative is greater than the derivative threshold, it is determined that the lithium battery has abnormal capacity loss and temperature rise, and the lithium battery is determined to be faulty.

[0177] If the battery temperature is less than or equal to the temperature threshold, and the inflection point derivative is greater than the derivative threshold, the lithium battery is judged to be in a normal discharge state, that is, the lithium battery may have a large capacity loss due to internal chemical reactions.

[0178] Taking steps S703 to S706 as an example, if the derivative threshold is set to 0.001 and the temperature threshold is 40 degrees Celsius, if the inflection point derivative is 0.01, the inflection point derivative is greater than the derivative threshold, and the measured battery temperature is 50 degrees Celsius. Since the battery temperature is greater than the temperature threshold and the inflection point derivative is greater than the derivative threshold, it is determined that the lithium battery is faulty and needs to be replaced in time.

[0179] The implementation principle of this embodiment is: judging whether a lithium battery fails based on the inflection point and the battery temperature of the lithium battery, which effectively improves the accuracy of judging whether a lithium battery fails.

[0180] An embodiment of the present application also discloses a terminal device, including a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein when the processor executes the computer program, the lithium battery charge and discharge function detection and management method in the above embodiment is adopted.

[0181] The terminal device may be a computer device such as a desktop computer, a laptop computer or a cloud server, and the terminal device includes but is not limited to a processor and a memory. For example, the terminal device may also include input and output devices, a network access device and a bus.

[0182] Among them, the processor can adopt a central processing unit (CPU). Of course, according to actual usage, other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. can also be adopted. The general-purpose processor can adopt a microprocessor or any conventional processor, etc., and this application does not impose any restrictions on this.

[0183] Among them, the memory can be an internal storage unit of the terminal device, such as a hard disk or memory of the terminal device, or it can be an external storage device of the terminal device, such as a plug-in hard disk, a smart memory card (SMC), a secure digital card (SD) or a flash memory card (FC) equipped on the terminal device, and the memory can also be a combination of an internal storage unit and an external storage device of the terminal device. The memory is used to store computer programs and other programs and data required by the terminal device. The memory can also be used to temporarily store data that has been output or is to be output, and this application does not impose any restrictions on this.

[0184] Among them, through this terminal device, the lithium battery charging and discharging function detection and management method in the above embodiment is stored in the memory of the terminal device, and is loaded and executed on the processor of the terminal device for easy use.

[0185] The embodiment of the present application further discloses a computer-readable storage medium, and the computer-readable storage medium stores a computer program, wherein when the computer program is executed by a processor, the lithium battery charge and discharge function detection and management method in the above embodiment is adopted.

[0186] Among them, the computer program can be stored in a computer-readable medium, the computer program includes computer program code, the computer program code can be in the form of source code, object code, executable file or certain middleware, etc. The computer-readable medium includes any entity or device that can carry the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal and software distribution medium, etc. It should be noted that the computer-readable medium includes but is not limited to the above-mentioned components.

[0187] Among them, through this computer-readable storage medium, the lithium battery charge and discharge function detection and management method in the above embodiment is stored in a computer-readable storage medium, and is loaded and executed on a processor to facilitate the storage and application of the above method.

[0188] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A lithium battery charge and discharge function detection and management method, characterized in that: include: Obtaining the number of cycles of the lithium battery, and obtaining the remaining cycle life of the lithium battery based on the number of cycles and preset factory information; Get the charging efficiency and usage time of lithium batteries; Obtaining a life grade of the lithium battery based on the charging efficiency and the usage time; Obtaining a life range corresponding to a life grade based on a preset life grade database; Determining whether the remaining cycle life falls within the life range; If the remaining cycle life falls within the life range, it is determined that the charging and discharging functions of the lithium battery are normal; If the remaining cycle life does not fall within the life range, it is determined that the charging and discharging function of the lithium battery is abnormal; Wherein, obtaining the charging efficiency of the lithium battery includes: Obtaining the charging capacity and charging time of the lithium battery at every preset time period; After the lithium battery is charged, the discharge amount of the lithium battery when it is discharged to a preset termination voltage and the discharge time when the lithium battery is discharged to the preset termination voltage are obtained; Substituting the charge amount, the charge time, the discharge amount and the discharge time into a preset charge efficiency formula to obtain a charge efficiency; The charging efficiency formula is as follows: Y=(m×t1) / (n×t2)*100%; Among them, Y is the charging efficiency, m is the discharge amount, t1 is the discharge time, n is the charge amount, and t2 is the charging time; The lifespan level includes a first lifespan level, a second lifespan level and a third lifespan level; the first lifespan level is greater than the second lifespan level, and the second lifespan level is greater than the third lifespan level; The obtaining of the life grade of the lithium battery based on the charging efficiency and the usage time includes: Determining whether the charging efficiency is lower than a preset efficiency threshold; If the charging efficiency is not lower than the efficiency threshold, determining that the life level of the remaining cycle life is the first level; If the charging efficiency is lower than the efficiency threshold, determining whether the usage time of the lithium battery is greater than a preset time threshold; If the usage time of the lithium battery is not greater than the time threshold, determining that the life level of the remaining cycle life is the second level; If the usage time of the lithium battery is greater than the time threshold, it is determined that the life level of the remaining cycle life is the third level.

2. A lithium battery charge and discharge function detection and management method according to claim 1, characterized in that: The obtaining of the number of cycles of the lithium battery and obtaining the remaining cycle life of the lithium battery based on the number of cycles and preset factory information includes: Get the number of times the lithium battery is fully charged and fully discharged; Based on the number of full charges and the number of full discharges, a cycle number is obtained; Based on the preset factory information of the lithium battery, obtain the cycle life of the lithium battery; The remaining cycle life is obtained by subtracting the number of cycles from the number of cycle life.

3. A lithium battery charge and discharge function detection and management method according to claim 1, characterized in that: Get the usage time of lithium battery, including: Based on the factory information, obtaining the factory time of the lithium battery; Get the current time; The absolute value of the time difference between the current time and the factory time is calculated to obtain the usage time of the lithium battery.

4. A lithium battery charge and discharge function detection and management method according to claim 1, characterized in that: After the lithium battery is charged, the discharge amount of the lithium battery discharged to a preset termination voltage and the discharge time of the lithium battery discharged to the preset termination voltage are obtained, including: Obtain the working voltage of the lithium battery corresponding to each discharge moment in real time; Generate a visual discharge curve based on the discharge time and the corresponding working voltage; Calculating the first-order derivative of the visualized discharge curve and generating a visualized derivative curve; Obtaining the inflection point of the visualized derivative curve based on a preset inflection point detection algorithm; Determining whether the lithium battery fails based on the inflection point; If a fault occurs, an alarm message will be issued; If no fault occurs, a step of obtaining the life grade of the lithium battery based on the charging efficiency and the usage time is performed.

5. A lithium battery charge and discharge function detection and management method according to claim 4, characterized in that: The determining whether the lithium battery fails based on the inflection point includes: Determining whether the inflection point changes the upward direction of the visualized derivative curve; If the inflection point changes the upward direction of the visualized derivative curve, obtaining the inflection point derivative corresponding to the inflection point; Determining whether the inflection point derivative is greater than a preset derivative threshold; If the inflection point derivative is greater than the derivative threshold, obtaining the battery temperature of the lithium battery; Determining whether the battery temperature is greater than a preset temperature threshold; If the battery temperature is greater than the temperature threshold, it is determined that the lithium battery fails.

6. A terminal device, characterized in that: The device includes: a memory, a processor, and a lithium battery charge and discharge function detection management program stored in the memory and executable on the processor, wherein the lithium battery charge and discharge function detection management program is configured to implement the lithium battery charge and discharge function detection management method as described in any one of claims 1 to 5.

7. A computer-readable storage medium, wherein a computer program is stored in the computer-readable storage medium, characterized in that: When the computer program is loaded and executed by a processor, the method according to any one of claims 1 to 5 is adopted.

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