Short plate cell identification method and device, energy storage system and computer equipment

Abstract

The invention relates to an identification method and device of a short-plate battery cell, an energy storage system and computer equipment, and the identification method of the short-plate battery cell comprises the steps: responding to a charging mode of a battery pack in an actual operation process, and determining a first battery cell with the minimum voltage in each battery cell in the battery pack; determining a second battery cell corresponding to the maximum voltage offset according to the voltage offset of each battery cell in the battery pack before and after charging; when the first battery cell and the second battery cell are the same battery cell, marking the first battery cell as a suspected short-plate battery cell; and when the number of times that the first battery cell is marked as the suspected short-plate battery cell reaches a preset number of times, determining that the first battery cell is the short-plate battery cell. Through the method and the device, the problems that the analysis efficiency is relatively low and the short-plate battery cell cannot be positioned in time are solved, the analysis efficiency is improved, and the short-plate battery cell is positioned in time.

Description

Technical Field

[0001] This application relates to the technical field of battery management, and particularly to a method and device for identifying short-plate battery cells, an energy storage system, and a computer device. Background Art

[0002] With the rapid development of the energy storage industry, the installed capacity of energy storage cabinets has shown a significant growth trend year by year. An energy storage cabinet battery pack usually contains a large number of battery cells. Once there is a large deviation in the capacity of a certain battery cell in the battery pack from the states of other battery cells, that is, a short-plate battery cell appears, the performance of the battery pack will drop significantly. Therefore, it is necessary to accurately identify the short-plate battery cell and replace it in time to ensure the performance of the battery pack.

[0003] In the existing methods for identifying short-plate battery cells, usually, battery packs with performance degradation are screened out, and charge-discharge experiments are performed on the battery packs to determine the short-plate battery cells. However, this method has low analysis efficiency and cannot locate the short-plate battery cells in time.

[0004] In view of the low analysis efficiency and the inability to locate the short-plate battery cells in time in the related technologies, no effective solution has been proposed yet. Summary of the Invention

[0005] In this embodiment, a method and device for identifying short-plate battery cells, an energy storage system, and a computer device are provided to solve the problem of low analysis efficiency and inability to locate the short-plate battery cells in time in the related technologies.

[0006] In a first aspect, in this embodiment, a method for identifying short-plate battery cells is provided, and the method includes:

[0007] In response to a battery pack entering a charging mode during actual operation, determining a first battery cell with the minimum voltage among the battery cells in the battery pack;

[0008] Determining a second battery cell corresponding to the maximum voltage offset according to the voltage offset of each battery cell in the battery pack before and after charging;

[0009] When the first battery cell and the second battery cell are the same battery cell, marking the first battery cell as a suspected short-plate battery cell;

[0010] When the number of times the first battery cell is marked as the suspected short-plate battery cell reaches a preset number of times, determining that the first battery cell is a short-plate battery cell.

[0011] In some of the embodiments, after determining the second battery cell corresponding to the maximum voltage offset according to the voltage offset of each battery cell in the battery pack before and after charging, the method further includes:

[0012] Generating a maximum voltage curve of each battery cell during the charging process;

[0013] Determine the maximum slope point of the maximum voltage curve;

[0014] Determine the outlier cells among the cells at the target time corresponding to the maximum slope point;

[0015] When the first cell, the second cell, and the outlier cell are all the same cell, determine that the first cell is the short board cell.

[0016] In some embodiments, the determining the maximum slope point of the maximum voltage curve includes:

[0017] Obtain the voltage and the battery pack power corresponding to different data points in the maximum voltage curve;

[0018] Generate a power-voltage change slope graph based on the voltage and the battery pack power corresponding to each data point; the power-voltage change slope graph is used to reflect the relationship between the change rate of the battery pack power and the voltage;

[0019] Determine the maximum slope point of the maximum voltage curve according to the voltage corresponding to the peak point in the power-voltage change slope graph.

[0020] In some embodiments, the determining the outlier cells among the cells at the target time corresponding to the maximum slope point includes:

[0021] Determine the target time corresponding to the maximum slope point;

[0022] Obtain the voltage of each cell at the target time and the average voltage of the cells;

[0023] Determine the deviation amount between the voltage of each cell and the average voltage of the cells based on the voltage of each cell and the average voltage of the cells;

[0024] Select the outlier cells among the cells according to the deviation amount corresponding to each cell.

[0025] In some embodiments, the deviation amount is the standard deviation distance; the selecting the outlier cells among the cells according to the deviation amount corresponding to each cell includes:

[0026] Compare each standard deviation distance with a first preset threshold;

[0027] According to the comparison result, select the cells with the standard deviation distance greater than the first preset threshold as the outlier cells.

[0028] In some of these embodiments, after determining the first battery cell with the minimum voltage among the battery cells in the battery pack in response to the battery pack entering the charging mode during actual operation, the method further includes:

[0029] In response to the battery pack entering the charging mode, determining the maximum voltage of each of the battery cells;

[0030] When the difference between the maximum voltage and the minimum voltage is greater than a second preset threshold, determining the voltage offset of each of the battery cells in the battery pack before and after charging.

[0031] In a second aspect, in this embodiment, a device for identifying a short-board battery cell is provided. The device includes:

[0032] A screening module, configured to determine the first battery cell with the minimum voltage among the battery cells in the battery pack in response to the battery pack entering the charging mode during actual operation;

[0033] An analysis module, configured to determine a second battery cell corresponding to the maximum voltage offset according to the voltage offset of each of the battery cells in the battery pack before and after charging;

[0034] A detection module, configured to mark the first battery cell as a suspected short-board battery cell when the first battery cell and the second battery cell are the same battery cell;

[0035] A judgment module, configured to determine that the first battery cell is a short-board battery cell when the number of times the first battery cell is marked as the suspected short-board battery cell reaches a preset number of times.

[0036] In a third aspect, in this embodiment, an energy storage system is provided. The system includes a battery pack and a single-chip microcomputer; the single-chip microcomputer is connected to the battery pack and is configured to execute the method for identifying a short-board battery cell described in the first aspect above.

[0037] In a fourth aspect, in this embodiment, a computer device is provided, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the method for identifying a short-board battery cell described in the first aspect above is implemented.

[0038] In a fifth aspect, in this embodiment, a storage medium is provided, on which a computer program is stored. When the program is executed by a processor, the method for identifying a short-board battery cell described in the first aspect above is implemented.

[0039] Compared with the related art, the method, device, energy storage system and computer device for identifying short-plate battery cells provided in this embodiment determine the first battery cell with the minimum voltage among the battery cells in the battery pack by responding to the battery pack entering the charging mode during the actual operation process; determine the second battery cell corresponding to the maximum voltage offset according to the voltage offset of each battery cell in the battery pack before and after charging; when the first battery cell and the second battery cell are the same battery cell, mark the first battery cell as a suspected short-plate battery cell; when the number of times the first battery cell is marked as a suspected short-plate battery cell reaches a preset number of times, determine the first battery cell as a short-plate battery cell, solving the problem of low analysis efficiency and inability to locate short-plate battery cells in a timely manner, and realizing the improvement of analysis efficiency and timely location of short-plate battery cells.

[0040] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more concise and understandable. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings described herein are used to provide a further understanding of the present application and form a part of the present application. The illustrative embodiments and descriptions thereof of the present application are used to explain the present application and do not constitute an improper limitation of the present application. In the drawings:

[0042] Figure 1 is a hardware structure block diagram of a terminal device for the method of identifying short-plate battery cells provided in an embodiment of the present application;

[0043] Figure 2 is a flowchart of the method of identifying short-plate battery cells provided in an embodiment of the present application;

[0044] Figure 3 is a schematic diagram of the maximum voltage curve provided in an embodiment of the present application;

[0045] Figure 4 is a graph of the slope of the power-voltage change provided in an embodiment of the present application;

[0046] Figure 5 is a schematic diagram of the maximum voltage curve provided in another embodiment of the present application;

[0047] Figure 6 is a flowchart of the method of identifying short-plate battery cells provided in a preferred embodiment of the present application;

[0048] Figure 7 is a structure block diagram of the device for identifying short-plate battery cells provided in an embodiment of the present application.

[0049] In the figure: 102, processor; 104, memory; 106, transmission device; 108, input / output device; 10, screening module; 20, analysis module; 30, detection module; 40, judgment module. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0050] To more clearly understand the purpose, technical solution and advantages of this application, the following describes and explains this application in combination with the accompanying drawings and embodiments.

[0051] Unless otherwise defined, the technical terms or scientific terms involved in this application shall have the general meaning understood by those with ordinary skills in the technical field to which this application belongs. In this application, words such as "a", "one", "a kind of", "the", "these" and the like do not indicate a limitation in quantity, and they can be singular or plural. The terms "including", "comprising", "having" and any variants thereof involved in this application are intended to cover non-exclusive inclusion; for example, a process, method, system, product or device including a series of steps or modules (units) is not limited to the listed steps or modules (units), but may include unlisted steps or modules (units), or may include other steps or modules (units) inherent in these processes, methods, products or devices. The terms "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether directly or indirectly connected. The "plurality" involved in this application means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, and B exists alone. Usually, the character " / " indicates that the objects associated before and after are in an "or" relationship. The terms "first", "second", "third" and the like involved in this application only distinguish similar objects and do not represent a specific sorting for the objects.

[0052] The method embodiment provided in this embodiment can be executed on a terminal, a computer or a similar computing device. For example, running on a terminal Figure 1 is the hardware structure block diagram of the terminal for the method of identifying the short-board battery cells in this embodiment. As Figure 1 shown, the terminal may include one or more ( Figure 1 only one is shown in Figure 1 the processor 102 and the memory 104 for storing data, where the processor 102 may include, but is not limited to, a processing device such as a microprocessor MCU or a programmable logic device FPGA. The above terminal may further include a transmission device 106 for communication functions and an input / output device 108. Those of ordinary skill in the art can understand that Figure 1 the structure shown in Figure 1 is only schematic and does not limit the structure of the above terminal. For example, the terminal may further include more or fewer components than

[0053] The memory 104 can be used to store computer programs, such as software programs and modules of application software, such as the computer program corresponding to the method for identifying short-plate battery cells in this embodiment. The processor 102 executes various functional applications and data processing by running the computer programs stored in the memory 104, that is, implements the above method. The memory 104 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memories. In some instances, the memory 104 may further include a memory remotely provided relative to the processor 102, and these remote memories can be connected to the terminal through a network. Examples of the above network include but are not limited to the Internet, enterprise intranet, local area network, mobile communication network, and combinations thereof.

[0054] The transmission device 106 is used to receive or send data via a network. The above network includes the wireless network provided by the communication provider of the terminal. In one instance, the transmission device 106 includes a network adapter (abbreviated as NIC), which can be connected to other network devices through a base station and thus can communicate with the Internet. In one instance, the transmission device 106 can be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0055] In this embodiment, a method for identifying short-plate battery cells is provided. Figure 2 is a flowchart of the method for identifying short-plate battery cells in this embodiment, as Figure 2 shown, this process includes the following steps:

[0056] Step S210, in response to the battery pack entering the charging mode during the actual operation process, determine the first battery cell with the minimum voltage among the battery cells in the battery pack;

[0057] Step S220, according to the voltage offset of each battery cell in the battery pack before and after charging, determine the second battery cell corresponding to the maximum voltage offset;

[0058] Step S230, when the first battery cell and the second battery cell are the same battery cell, mark the first battery cell as a suspected short-plate battery cell;

[0059] Step S240, when the number of times the first battery cell is marked as a suspected short-plate battery cell reaches a preset number of times, determine the first battery cell as a short-plate battery cell.

[0060] Specifically, during the actual operation of the battery pack, when the battery pack changes from the non-charging mode to the charging mode, collect the current voltage of each battery cell in the battery pack, and screen out the first battery cell with the current minimum voltage from each battery cell, record the single-cell serial number of the first battery cell and the voltage V of each battery celli After the battery pack finishes charging, record the voltage V of each battery cell at this time. j Calculate the voltage offset ΔV of each battery cell in the battery pack before and after charging. th = V j - V i Screen out the maximum voltage offset and record the serial number of the second battery cell corresponding to the maximum voltage offset.

[0061] Furthermore, determine whether the serial number of the first battery cell is the same as that of the second battery cell. If the serial numbers of the first battery cell and the second battery cell are different, it indicates that neither the first battery cell nor the second battery cell is a suspected short board battery cell; if the serial numbers of the first battery cell and the second battery cell are the same, that is, the first battery cell and the second battery cell are the same battery cell, then mark the first battery cell as a suspected short board battery cell. During the cyclic charging process of the battery pack, each charging stage monitors each battery cell in the battery pack through the above identification method until the number of times the first battery cell is marked as a suspected short board battery cell reaches the preset number, determine that the first battery cell is a short board battery cell, and give an early warning.

[0062] It should be noted that in this embodiment, by using the method of screening the pressure difference, it can effectively remove the interference of the voltage in the plateau period on the calculation result, avoid misjudgment caused by poor consistency of the battery cell power, and make the identification calculation result of the short board battery cell more accurate.

[0063] In addition, this embodiment can be combined with a temperature compensation mechanism. When determining the first battery cell and the second battery cell, synchronously obtain the real-time temperature data of each battery cell, comprehensively judge the short board battery cell in the battery pack based on the real-time temperature and the battery cell voltage data, or based on the sequential data during the operation of each battery cell, and combine the neural network model to assist in judging the prediction result of the health status of the battery cell, so as to reduce the detection time and improve the accuracy and efficiency of identification.

[0064] In the existing short board battery cell identification methods, usually a battery pack with performance attenuation is screened out, and the short board battery cell is determined by performing charge and discharge experiments on the battery pack. However, this method has a low analysis efficiency and cannot locate the short board battery cell in time.

[0065] Compared with the prior art, in response to the battery pack entering the charging mode during the actual operation process, the first battery cell with the minimum voltage among the battery cells in the battery pack is determined; according to the voltage offset of each battery cell in the battery pack before and after charging, the second battery cell corresponding to the maximum voltage offset is determined; when the first battery cell and the second battery cell are the same battery cell, the first battery cell is marked as a suspected short-board battery cell; when the number of times the first battery cell is marked as a suspected short-board battery cell reaches a preset number of times, the first battery cell is determined to be a short-board battery cell. Based on this, a short-board battery cell identification strategy applicable to the actual operation process is adopted. When the capacity performance of the battery pack decays, the short-board battery cell can be quickly located and an early warning can be given, solving the problem of low analysis efficiency and inability to locate the short-board battery cell in time, and realizing the improvement of the analysis efficiency and the timely location of the short-board battery cell.

[0066] In some of these embodiments, after determining the second battery cell corresponding to the maximum voltage offset according to the voltage offset of each battery cell in the battery pack before and after charging, the above-mentioned short-board battery cell identification method further includes the following steps:

[0067] Generate the maximum voltage curve of each battery cell during the charging process;

[0068] Determine the maximum slope point of the maximum voltage curve;

[0069] Determine the outlier battery cell among the battery cells at the target moment corresponding to the maximum slope point;

[0070] When the first battery cell, the second battery cell and the outlier battery cell are all the same battery cell, determine that the first battery cell is a short-board battery cell.

[0071] Specifically, for the middle stage of charging, determine the maximum voltage of each battery cell at each moment, and generate the corresponding maximum voltage curve according to the maximum voltage at different moments. As Figure 3 shown, the maximum voltage curve takes the charging duration of this charging as the abscissa and the maximum voltage among the voltages of each battery cell as the ordinate.

[0072] Further, calculate the slope corresponding to each data point on the maximum voltage curve, select the maximum slope point, that is, the data point where the slope on the maximum voltage curve obtains the maximum value, and use this data point as the screening point for the outlier battery cell. Determine the target moment corresponding to the maximum slope point, obtain the voltage of each battery cell at the target moment and the voltage mean value of each battery cell, calculate the deviation between the voltage of each battery cell and the voltage mean value based on the voltage of each battery cell and the voltage mean value of each battery cell, and select the battery cell with a deviation greater than the first preset threshold as the outlier battery cell according to the deviation corresponding to each battery cell, and record the monomer serial number of the outlier battery cell. Among them, the deviation includes, but is not limited to, the standard deviation distance, the absolute deviation and the relative deviation.

[0073] After that, it is determined whether the cell numbers of the first cell, the second cell, and the outlier cell are all the same. If the cell numbers of any two of the first cell, the second cell, and the outlier cell are different, it indicates that none of the first cell, the second cell, and the outlier cell is a short-board cell; if the cell numbers of the first cell, the second cell, and the outlier cell are all the same, that is, the first cell, the second cell, and the outlier cell are the same cell, then it is determined that the first cell is a short-board cell.

[0074] Through this embodiment, the maximum voltage curve of each cell during charging is generated, the maximum slope point of the maximum voltage curve is determined, the outlier cell in each cell at the target time corresponding to the maximum slope point is determined. When the first cell, the second cell, and the outlier cell are all the same cell, it is determined that the first cell is a short-board cell. In this way, by detecting the outlier cell during charging, the identification of the short-board cell is realized, which helps to improve the accuracy and efficiency of the short-board cell identification.

[0075] In some of these embodiments, determining the maximum slope point of the maximum voltage curve includes the following steps:

[0076] Obtain the voltages and battery pack powers corresponding to different data points in the maximum voltage curve;

[0077] Based on the voltages and battery pack powers corresponding to each data point, generate a power-voltage change slope graph; the power-voltage change slope graph is used to reflect the relationship between the change rate of the battery pack power and the voltage;

[0078] According to the voltage corresponding to the peak point in the power-voltage change slope graph, determine the maximum slope point of the maximum voltage curve.

[0079] Specifically, obtain the voltage V and battery pack power Q corresponding to different data points in the maximum voltage curve, and generate a power-voltage change slope graph based on the voltages and battery pack powers corresponding to each data point. As Figure 4 shown, the power-voltage change slope graph has the voltage as the abscissa and the change rate of the power with respect to the voltage (dQ / dV) as the ordinate, and is used to reflect the relationship between the change rate of the battery pack power and the voltage.

[0080] Further, determine the peak point in the power-voltage change slope graph (such as Figure 4 the point A shown), and according to the voltage corresponding to the peak point, determine the maximum slope point of the maximum voltage curve, that is, find the voltage corresponding to the peak point on the maximum voltage curve, and the data point where this voltage is located is the maximum slope point of the maximum voltage curve.

[0081] Through this embodiment, the voltages and the battery pack power corresponding to different data points on the maximum voltage curve are obtained. Based on the voltages and the battery pack power corresponding to each data point, a power-voltage change slope graph is generated. The power-voltage change slope graph is used to reflect the relationship between the change rate of the battery pack power and the voltage. Furthermore, according to the voltage corresponding to the peak point in the power-voltage change slope graph, the maximum slope point of the maximum voltage curve is determined, thereby accurately calculating the maximum slope point of the maximum voltage curve, which helps to improve the accuracy of subsequent screening of outlier battery cells.

[0082] In some of these embodiments, determining the outlier battery cells in each battery cell at the target time corresponding to the maximum slope point includes the following steps:

[0083] Determine the target time corresponding to the maximum slope point;

[0084] Obtain the voltage of each battery cell at the target time, and the average voltage of each battery cell;

[0085] Based on the voltage of each battery cell and the average voltage of each battery cell, determine the deviation amount between the voltage of each battery cell and the average voltage;

[0086] Select the outlier battery cells in each battery cell according to the deviation amount corresponding to each battery cell.

[0087] Specifically, as Figure 5 shown, on the maximum voltage curve, determine the target time corresponding to the maximum slope point. Obtain the voltage of each battery cell at the target time and the average voltage of each battery cell. Based on the voltage of each battery cell and the average voltage of each battery cell, calculate the deviation amount between the voltage of each battery cell and the average voltage, such as the standard deviation distance, absolute deviation, and relative deviation between the voltage of each battery cell and the average voltage, which are not limited herein.

[0088] Further, compare the deviation amount corresponding to each battery cell with a first preset threshold, and screen out the battery cells with a deviation amount greater than the first preset threshold as outlier battery cells, and record the monomer serial numbers of the outlier battery cells for subsequent comparison with the first battery cell and the second battery cell.

[0089] Through this embodiment, the target time corresponding to the maximum slope point is determined, the voltage of each battery cell at the target time is obtained, and the average voltage of each battery cell. Based on the voltage of each battery cell and the average voltage of each battery cell, the deviation amount between the voltage of each battery cell and the average voltage is determined. According to the deviation amount corresponding to each battery cell, the outlier battery cells in each battery cell are selected, thereby accurately screening out the outlier battery cells.

[0090] In some of these embodiments, the deviation amount is the standard deviation distance; selecting the outlier battery cells in each battery cell according to the deviation amount corresponding to each battery cell includes the following steps:

[0091] Compare each standard deviation distance with a first preset threshold;

[0092] According to the comparison result, select the battery cells with standard deviation distances greater than the first preset threshold as outlier battery cells.

[0093] Specifically, pre-calculate the absolute deviation between the battery cell voltage and the voltage mean value, and calculate the ratio between the absolute deviation and the standard deviation of each battery cell voltage to obtain the standard deviation distance between the voltage of each battery cell and the voltage mean value, and use the standard deviation distance as the deviation amount of the corresponding battery cell.

[0094] Furthermore, compare each standard deviation distance with the first preset threshold to determine whether the standard deviation distance is greater than the first preset threshold, and select the battery cells with standard deviation distances greater than the first preset threshold as outlier battery cells.

[0095] Through this embodiment, using the standard deviation distance as the deviation amount, compare each standard deviation distance with the first preset threshold, and according to the comparison result, select the battery cells with standard deviation distances greater than the first preset threshold as outlier battery cells, so as to improve the accuracy of screening outlier battery cells.

[0096] In some of these embodiments, in response to the battery pack entering the charging mode during the actual operation process, after determining the first battery cell with the minimum voltage among the battery cells in the battery pack, the above method for identifying short-board battery cells further includes the following steps:

[0097] In response to the battery pack entering the charging mode, determine the maximum voltage of each battery cell;

[0098] When the difference between the maximum voltage and the minimum voltage is greater than a second preset threshold, determine the voltage offset of each battery cell in the battery pack before and after charging.

[0099] Specifically, during the actual operation process of the battery pack, when the battery pack switches from the non-charging mode to the charging mode, collect the current voltages of the battery cells in the battery pack, and screen out the first battery cell with the current minimum voltage V min and the third battery cell with the maximum voltage V max from the battery cells.

[0100] Furthermore, calculate the difference between the maximum voltage and the minimum voltage, compare the difference between the maximum voltage and the minimum voltage with the second preset threshold. If the difference between the maximum voltage and the minimum voltage is greater than the second preset threshold, for example, when the second preset threshold is 6 mV, V min -V max > 6 mV, then after the battery pack finishes charging, record the voltage V j of each battery cell, and calculate the voltage offset ΔV th of each battery cell in the battery pack before and after charging.

[0101] In this embodiment, in response to the battery pack entering the charging mode, the maximum voltage of each battery cell is determined. When the difference between the maximum voltage and the minimum voltage is greater than the second preset threshold, the voltage offset of each battery cell in the battery pack before and after charging is determined, so as to pre-judge whether there is an obvious voltage difference between the battery cells in the battery pack, which helps to analyze and locate the problematic battery cells subsequently and improve the data validity.

[0102] The following describes and illustrates this embodiment through preferred embodiments.

[0103] Figure 6 is a flowchart of the method for identifying the short-board battery cell in this preferred embodiment, as Figure 6 shown. The method for identifying the short-board battery cell includes the following steps:

[0104] Step S610, in response to the battery pack entering the charging mode during the actual operation process, determine the first battery cell with the minimum voltage and the third battery cell with the maximum voltage among the battery cells in the battery pack;

[0105] Step S620, when the difference between the maximum voltage and the minimum voltage is greater than the second preset threshold, determine the voltage offset of each battery cell in the battery pack before and after charging;

[0106] Step S630, according to the voltage offset of each battery cell in the battery pack before and after charging, determine the second battery cell corresponding to the maximum voltage offset;

[0107] Step S640, generate the maximum voltage curve of each battery cell during the charging process and determine the maximum slope point of the maximum voltage curve;

[0108] Step S650, determine the target time corresponding to the maximum slope point, obtain the voltage of each battery cell at the target time, and the voltage average value of each battery cell;

[0109] Step S660, based on the voltage of each battery cell and the voltage average value of each battery cell, determine the standard deviation distance between the voltage of each battery cell and the voltage average value;

[0110] Step S670, compare each standard deviation distance with the first preset threshold; according to the comparison result, select the battery cell with the standard deviation distance greater than the first preset threshold as the outlier battery cell;

[0111] Step S680, when the first battery cell, the second battery cell and the outlier battery cell are all the same battery cell, determine the first battery cell as the short-board battery cell.

[0112] In this embodiment, in response to the battery pack entering the charging mode during the actual operation process, the first battery cell with the minimum voltage and the third battery cell with the maximum voltage among the battery cells in the battery pack are determined. When the difference between the maximum voltage and the minimum voltage is greater than the second preset threshold, the voltage offset of each battery cell in the battery pack before and after charging is determined, and the second battery cell corresponding to the maximum voltage offset is determined according to the voltage offset of each battery cell in the battery pack before and after charging.

[0113] Further, a maximum voltage curve of each battery cell during the charging process is generated, and the maximum slope point of the maximum voltage curve is determined. Then, the target time corresponding to the maximum slope point is determined, the voltage of each battery cell and the voltage average value of each battery cell at the target time are obtained. Based on the voltage of each battery cell and the voltage average value of each battery cell, the standard deviation distance between the voltage of each battery cell and the voltage average value is determined. The standard deviation distance of each battery cell is compared with the first preset threshold. According to the comparison result, the battery cell with a standard deviation distance greater than the first preset threshold is selected as the outlier battery cell. When the first battery cell, the second battery cell, and the outlier battery cell are the same battery cell, the first battery cell is determined as the short board battery cell, which solves the problem of low analysis efficiency and inability to locate the short board battery cell in time, and realizes improving the analysis efficiency and locating the short board battery cell in time.

[0114] It should be noted that the steps shown in the above process or the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions. And although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0115] In this embodiment, an identification device for the above-mentioned short board battery cell is also provided. This device is used to implement the above-mentioned embodiment and the preferred implementation manners, and those that have been described will not be repeated here. The following terms such as "module", "unit", "sub-unit", etc. can be a combination of software and / or hardware that can achieve a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware is also possible and contemplated.

[0116] Figure 7 is the structural block diagram of the identification device for the short board battery cell in this embodiment, as Figure 7 shown, this device includes:

[0117] The screening module 10 is used to determine the first battery cell with the minimum voltage among the battery cells in the battery pack in response to the battery pack entering the charging mode during the actual operation process;

[0118] The analysis module 20 is used to determine the second battery cell corresponding to the maximum voltage offset according to the voltage offset of each battery cell in the battery pack before and after charging;

[0119] The detection module 30 is used to mark the first battery cell as a suspected short-board battery cell when the first battery cell and the second battery cell are the same battery cell.

[0120] The judgment module 40 is used to determine that the first battery cell is a short-board battery cell when the number of times the first battery cell is marked as a suspected short-board battery cell reaches a preset number of times.

[0121] Through the device provided in this embodiment, in response to the battery pack entering the charging mode during the actual operation process, the first battery cell with the minimum voltage among the battery cells in the battery pack is determined; according to the voltage offset of each battery cell in the battery pack before and after charging, the second battery cell corresponding to the maximum voltage offset is determined; when the first battery cell and the second battery cell are the same battery cell, the first battery cell is marked as a suspected short-board battery cell; when the number of times the first battery cell is marked as a suspected short-board battery cell reaches a preset number of times, it is determined that the first battery cell is a short-board battery cell, which solves the problem of low analysis efficiency and inability to locate the short-board battery cell in a timely manner, and realizes improving the analysis efficiency and locating the short-board battery cell in a timely manner.

[0122] In some of these embodiments, the judgment module 40 is further used to generate the maximum voltage curve of each battery cell during charging; determine the maximum slope point of the maximum voltage curve; determine the outlier battery cell among each battery cell at the target moment corresponding to the maximum slope point; when the first battery cell, the second battery cell and the outlier battery cell are all the same battery cell, determine that the first battery cell is a short-board battery cell.

[0123] In some of these embodiments, the judgment module 40 is further used to obtain the voltage and the battery pack power corresponding to different data points in the maximum voltage curve; generate a power-voltage change slope diagram based on the voltage and the battery pack power corresponding to each data point; the power-voltage change slope diagram is used to reflect the relationship between the change rate of the battery pack power and the voltage; according to the voltage corresponding to the peak point in the power-voltage change slope diagram, determine the maximum slope point of the maximum voltage curve.

[0124] In some of these embodiments, the judgment module 40 is further used to determine the target moment corresponding to the maximum slope point; obtain the voltage of each battery cell at the target moment and the voltage average value of each battery cell; based on the voltage of each battery cell and the voltage average value of each battery cell, determine the deviation amount between the voltage of each battery cell and the voltage average value; according to the deviation amount corresponding to each battery cell, select the outlier battery cell among each battery cell.

[0125] In some of these embodiments, the judgment module 40 is further used to compare each standard deviation distance with a first preset threshold; according to the comparison result, select the battery cell with a standard deviation distance greater than the first preset threshold as the outlier battery cell.

[0126] In some of these embodiments, Figure 7Based on this, the device further includes an operation module, which is configured to determine the maximum voltage of each battery cell in response to the battery pack entering the charging mode; when the difference between the maximum voltage and the minimum voltage is greater than a second preset threshold, determine the voltage offset of each battery cell in the battery pack before and after charging.

[0127] It should be noted that each of the above modules can be a functional module or a program module, and can be implemented either by software or by hardware. For the modules implemented by hardware, each of the above modules can be located in the same processor; or each of the above modules can also be located in different processors in any combined form.

[0128] In this embodiment, an energy storage system is further provided, including a battery pack and a single-chip microcomputer; the single-chip microcomputer is connected to the battery pack and is configured to execute the steps in any one of the above method embodiments.

[0129] In this embodiment, a computer device is further provided, including a memory and a processor. A computer program is stored in the memory, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

[0130] Optionally, the above computer device may further include a transmission device and an input / output device, where the transmission device is connected to the above processor, and the input / output device is connected to the above processor.

[0131] Optionally, in this embodiment, the above processor may be configured to execute the following steps through a computer program:

[0132] S1. In response to the battery pack in the actual operation process entering the charging mode, determine the first battery cell with the minimum voltage among the battery cells in the battery pack;

[0133] S2. According to the voltage offset of each battery cell in the battery pack before and after charging, determine the second battery cell corresponding to the maximum voltage offset;

[0134] S3. When the first battery cell and the second battery cell are the same battery cell, mark the first battery cell as a suspected short board battery cell;

[0135] S4. When the number of times the first battery cell is marked as a suspected short board battery cell reaches a preset number of times, determine the first battery cell as a short board battery cell.

[0136] It should be noted that the specific examples in this embodiment can refer to the examples described in the above embodiments and optional implementation manners, and will not be elaborated in this embodiment.

[0137] In addition, in combination with the method for identifying defective cells provided in the above embodiments, a storage medium can also be provided in this embodiment to implement it. A computer program is stored on the storage medium; when the computer program is executed by a processor, the method for identifying any one of the defective cells in the above embodiments is implemented.

[0138] It should be understood that the specific embodiments described herein are only used to explain this application and not to limit it. According to the embodiments provided in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of this application.

[0139] Obviously, the accompanying drawings are only some examples or embodiments of this application. For those of ordinary skill in the art, this application can also be applied to other similar situations based on these drawings without creative efforts. Additionally, it can be understood that although the work done during the development process may be complex and time-consuming, for those of ordinary skill in the art, certain design, manufacturing, or production changes based on the technical content disclosed in this application are only conventional technical means and should not be regarded as insufficient disclosure of this application.

[0140] The term "embodiment" in this application means that the specific features, structures, or characteristics described in connection with the embodiments may be included in at least one embodiment of this application. The phrase appears in various positions in the specification and does not necessarily mean the same embodiment, nor does it mean being independent or alternative to other embodiments and mutually exclusive. Those of ordinary skill in the art can clearly or implicitly understand that the embodiments described in this application can be combined with other embodiments without conflict.

[0141] The above-described embodiments only represent several implementation manners of this application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of patent protection. It should be noted that for those of ordinary skill in the art, without departing from the concept of this application, several modifications and improvements can still be made, and these all belong to the protection scope of this application. Therefore, the protection scope of this application should be subject to the appended claims.

Claims

1. A method for identifying a short-plate battery cell, characterized in that, The method includes: In response to the battery pack entering the charging mode during the actual operation, determining a first battery cell with the minimum voltage among the battery cells in the battery pack; Determining a second battery cell corresponding to the maximum voltage offset according to the voltage offset of each battery cell in the battery pack before and after charging; When the first battery cell and the second battery cell are the same battery cell, marking the first battery cell as a suspected short-board battery cell; When the number of times the first battery cell is marked as the suspected short-board battery cell reaches a preset number of times, determining the first battery cell as a short-board battery cell.

2. The identification method of the short-plate battery cell according to claim 1, wherein After determining the second battery cell corresponding to the maximum voltage offset according to the voltage offset of each battery cell in the battery pack before and after charging, the method further includes: Generating a maximum voltage curve of each battery cell during charging; Determining the maximum slope point of the maximum voltage curve; Determining an outlier battery cell among the battery cells at the target moment corresponding to the maximum slope point; When the first battery cell, the second battery cell, and the outlier battery cell are all the same battery cell, determining the first battery cell as the short-board battery cell.

3. The method for identifying a short-plate battery cell according to claim 2, wherein The determining the maximum slope point of the maximum voltage curve includes: Obtaining the voltage and the battery pack power corresponding to different data points in the maximum voltage curve; Generating a power-voltage change slope diagram based on the voltage and the battery pack power corresponding to each data point; the power-voltage change slope diagram is used to reflect the relationship between the change rate of the battery pack power and the voltage; Determining the maximum slope point of the maximum voltage curve according to the voltage corresponding to the peak point in the power-voltage change slope diagram.

4. The identification method of the short-plate battery cell according to claim 2, wherein, The determining the outlier battery cell among the battery cells at the target moment corresponding to the maximum slope point includes: Determining the target moment corresponding to the maximum slope point; Obtaining the voltage of each battery cell at the target moment and the voltage average value of each battery cell; Based on the voltage of each battery cell and the voltage average value of each battery cell, determining the deviation amount between the voltage of each battery cell and the voltage average value; Selecting the outlier battery cell among the battery cells according to the deviation amount corresponding to each battery cell.

5. The identification method of the short-plate battery cell according to claim 4, characterized in that The deviation amount is the standard deviation distance; the selecting the outlier battery cell among the battery cells according to the deviation amount corresponding to each battery cell includes: Comparing each standard deviation distance with a first preset threshold; According to the comparison result, selecting the battery cell with the standard deviation distance greater than the first preset threshold as the outlier battery cell.

6. The method for identifying a short-plate battery cell according to claim 1, wherein After determining the first battery cell with the minimum voltage among the battery cells in the battery pack in response to the battery pack entering the charging mode during the actual operation, the method further includes: In response to the battery pack entering the charging mode, determining the maximum voltage of each battery cell; When the difference between the maximum voltage and the minimum voltage is greater than a second preset threshold, determining the voltage offset of each battery cell in the battery pack before and after charging.

7. An identification device for short-plate battery cells, characterized in that The device includes: A screening module, configured to determine a first battery cell with the minimum voltage among the battery cells in the battery pack in response to the battery pack entering the charging mode during the actual operation; An analysis module, configured to determine a second battery cell corresponding to the maximum voltage offset according to the voltage offset of each battery cell in the battery pack before and after charging; A detection module, configured to mark the first battery cell as a suspected short-board battery cell when the first battery cell and the second battery cell are the same battery cell; A judgment module, configured to determine that the first battery cell is a short-board battery cell when the number of times the first battery cell is marked as the suspected short-board battery cell reaches a preset number of times.

8. An energy storage system, characterized in that, The system includes a battery pack and a single-chip microcomputer; the single-chip microcomputer is connected to the battery pack and is configured to execute the steps of the method for identifying a short-board battery cell according to any one of claims 1 to 6.

9. A computer device, comprising a memory and a processor, characterized in that, A computer program is stored in the memory, and the processor is configured to run the computer program to execute the steps of the method for identifying a short-board battery cell according to any one of claims 1 to 6.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, the steps of the method for identifying a short-board battery cell according to any one of claims 1 to 6 are implemented.

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