Battery lithium precipitation detection method and device, computer equipment, medium and program product

Abstract

The invention relates to a battery lithium precipitation detection method and device, computer equipment, a medium and a program product, and the method comprises the steps: setting a plurality of detection regions on a positive pole piece of a target battery, and collecting reference signals corresponding to the detection regions; wherein the detection area comprises a pole piece center detection area and a pole piece edge detection area of the positive pole piece. Then collecting a negative signal of the target battery on the negative pole piece, and determining a negative parameter potential corresponding to each detection area according to the negative signal and each reference signal; and finally determining the lithium precipitation state of each detection area according to each negative parameter potential. According to the battery lithium precipitation detection method disclosed by the invention, the specific lithium precipitation position of the target battery can be detected in real time, the detection efficiency of battery lithium precipitation is greatly improved, and the reliability is high.

Description

Technical Field

[0001] The present application relates to the technical field of lithium-ion batteries, and in particular to a method, device, computer equipment, medium and program product for detecting lithium deposition in batteries. Background Art

[0002] Lithium-ion batteries are rechargeable batteries that use lithium ions to move between the positive and negative electrodes of the battery to store and release electrical energy. Lithium-ion batteries have high energy density and are lightweight, making them widely used in consumer electronics, electric vehicles, and power storage.

[0003] Lithium deposition is a phenomenon in which lithium ions are deposited directly on the negative electrode surface in the form of metallic lithium during the charging process of lithium-ion batteries. Battery lithium deposition will have a serious impact on the safety and service life of the battery. Traditional battery lithium deposition detection is mainly based on the analysis method of electrochemical reaction. This detection method requires the battery to be disassembled and analyzed after a long cycle. It cannot obtain the exact location of battery lithium deposition in real time, nor can it be improved in real time according to the lithium deposition situation. The detection efficiency is not high. Summary of the invention

[0004] Based on this, it is necessary to provide a battery lithium deposition detection method, device, computer equipment, medium and program product that can efficiently detect the battery lithium deposition state in response to the above technical problems.

[0005] In a first aspect, the present disclosure provides a battery lithium deposition detection method, the method comprising:

[0006] A plurality of detection areas are set on the positive electrode sheet of the target battery, and reference signals corresponding to each detection area are collected; wherein the detection area includes a center detection area and an edge detection area of ​​the positive electrode sheet;

[0007] Collect the negative electrode signal of the target battery at the negative electrode plate, and determine the negative reference potential corresponding to each detection area according to the negative electrode signal and each reference signal;

[0008] The lithium deposition state of each detection area is determined according to each negative reference potential.

[0009] In one embodiment, a plurality of detection areas are provided on the positive electrode plate of the target battery, including:

[0010] If the target battery is a wound battery, the electrode sheet center detection area is set in the electrode sheet center area of ​​the positive electrode sheet, and the electrode sheet edge detection area is set in the bottom edge area of ​​the positive electrode sheet, the top edge area of ​​the positive electrode sheet, and the R corner edge area of ​​the positive electrode sheet;

[0011] If the target battery is a laminated battery, a pole piece center detection area is set at the pole piece center area of ​​the positive pole piece, and a pole piece edge detection area is set at the bottom edge of the positive pole piece and the top edge area of ​​the positive pole piece;

[0012] The top edge area of ​​the positive electrode sheet corresponds to the position of the electrode lug and does not include the thinned area of ​​the positive electrode sheet.

[0013] In one embodiment, collecting reference signals corresponding to each detection area includes:

[0014] A reference electrode is provided in each detection area, and an insulating film is provided between the reference electrode and the positive electrode sheet;

[0015] The potential signal of each reference electrode is collected and used as a reference signal.

[0016] In one embodiment, collecting the potential signal of each reference electrode includes:

[0017] Get different charging strategies;

[0018] For each detection area, detection signals of the detection area under different charging strategies are collected; and a reference signal is determined based on each detection signal.

[0019] In one embodiment, the method further comprises:

[0020] A risk assessment model is obtained, and the lithium plating state corresponding to each detection area is input into the risk assessment model to obtain a risk assessment result of the target battery.

[0021] In one embodiment, the method further comprises:

[0022] Obtain historical data, and determine the lithium plating status and battery risk of each detection area based on the historical data; wherein the historical data includes historical detection data or historical disassembly data;

[0023] The risk assessment model is obtained based on lithium plating status and battery risk training.

[0024] In a second aspect, the present disclosure provides a battery lithium deposition detection device, the device comprising:

[0025] The area determination module is configured to: set a plurality of detection areas on the positive electrode sheet of the target battery, and collect reference signals corresponding to each detection area; wherein the detection area includes a center detection area and an edge detection area of ​​the positive electrode sheet;

[0026] The data acquisition module is configured to: acquire the negative electrode signal of the target battery at the negative electrode plate, and determine the negative reference potential corresponding to each detection area according to the negative electrode signal and each reference signal;

[0027] The detection module is configured to determine the lithium deposition state of each detection area according to each negative reference potential.

[0028] In a third aspect, the present disclosure provides a computer device including a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the method proposed in the first aspect when executing the computer program.

[0029] In a fourth aspect, the present disclosure provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the method proposed in the first aspect when the computer program is executed by a processor.

[0030] In a fifth aspect, the present disclosure provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the method proposed in the first aspect.

[0031] The above-mentioned battery lithium deposition detection method, device, computer equipment, storage medium and program product, when performing lithium deposition detection on the target battery, multiple detection areas are set on the positive electrode of the target battery, and reference signals corresponding to each detection area are collected. Among them, the detection area includes the electrode center detection area and the electrode edge detection area of ​​the positive electrode. Then the negative electrode signal of the target battery at the negative electrode is collected, and the negative reference potential corresponding to each detection area is determined according to the negative electrode signal and each reference signal. And finally, the lithium deposition state of each detection area is determined according to each negative reference potential. The battery lithium deposition detection method disclosed in the present invention sets a detection area on the positive electrode of the target battery, and collects the potential signals of each detection area of ​​the positive electrode, and the potential signal of the negative electrode, and then determines the negative reference potential of different detection areas, so as to judge the lithium deposition state of each detection area. The battery lithium deposition detection method disclosed in the present invention can detect the specific lithium deposition position of the target battery in real time, no longer sticking to the disassembly result of the battery, and greatly improves the detection efficiency of battery lithium deposition. The detection method disclosed in the present invention can timely improve and upgrade the battery according to the detected lithium plating state during battery design, and has high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the drawings required for use in the embodiments or the related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A schematic diagram of a process for detecting lithium deposition in a battery according to an embodiment;

[0034] Figure 2 is a schematic diagram of a detection area in one embodiment;

[0035] Figure 3 A schematic diagram of a process for detecting battery lithium deposition in another embodiment;

[0036] Figure 4 It is a structural block diagram of a battery lithium deposition detection device in one embodiment;

[0037] Figure 5 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0039] Lithium-ion batteries have high energy density and are lightweight, and are widely used in consumer electronics, electric vehicles, and power storage. The lithium plating problem inside lithium-ion batteries has always been the main reason that restricts the service life of lithium-ion batteries. Once the lithium plating phenomenon occurs, lithium-ion batteries will have serious safety problems.

[0040] In an exemplary embodiment, Figure 1 As shown, a method for detecting lithium deposition in a battery is provided, comprising the following steps 102 to 106. Among them:

[0041] Step 102, setting a plurality of detection areas on the positive electrode plate of the target battery, and collecting reference signals corresponding to each detection area; wherein the detection area includes a plate center detection area and a plate edge detection area of ​​the positive electrode plate.

[0042] The target battery is used to characterize the lithium-ion battery that needs to be tested for lithium plating. The target battery includes several electrode plates. The electrode plates can be metal foils coated with active materials. The electrode plates include positive electrode plates and negative electrode plates. During the charging process, the lithium ions in the target battery are released from the positive electrode material and migrate to the negative electrode; during the discharging process, the negative electrode material receives lithium ions and releases electrons to the external circuit to generate current.

[0043] In the present embodiment, when detecting lithium deposition in a battery, a plurality of different detection areas are set in the center area and the edge area of ​​the pole piece according to the structure of the battery, so as to increase the reliability of the lithium deposition detection and improve the accuracy of the lithium deposition detection.

[0044] In some specific implementations, the electrode edge detection area needs to avoid the thinning area and the electrode ear area of ​​the electrode to ensure the accuracy and reliability of lithium plating detection.

[0045] The thinning area of ​​the electrode plate is set at the top edge of the electrode plate, indicating the edge area where the thickness of the active material coated on the electrode plate is thinner. The thinning area can increase the specific surface area of ​​the active material of the electrode plate and improve the energy density and cycle life of the battery. During the cyclic charge and discharge process of lithium batteries, the active materials at the edge of the battery are often subjected to greater stress, resulting in battery capacity decay and shortened life. Therefore, by thinning the edge of the battery, the impact of the edge effect on battery performance can be reduced, and the cycle life and energy density of the battery can be improved.

[0046] The thinning area is located at the edge of the electrode sheet, and due to the large fluctuation in the surface density of the thinning area, it may cause instability in the battery lithium deposition detection and affect the reliability of lithium deposition detection. Therefore, when setting the edge detection area of ​​the electrode sheet of the target battery, it needs to be set at the edge of the electrode sheet away from the thinning area to improve the stability and reliability of lithium deposition detection.

[0047] The tab is an important part of the battery, and the current capacity of the tab is related to the safety and performance of the battery. Overcurrent means that the current passing through the tab exceeds the rated current value of the battery design. Insufficient current capacity of the tab area of ​​the target battery may affect the lithium plating detection in the tab area. Setting the edge detection area of ​​the pole piece away from the tab area of ​​the battery can ensure the accuracy of lithium plating detection.

[0048] Step 104 , collecting the negative electrode signal of the target battery at the negative electrode plate, and determining the negative reference potential corresponding to each detection area according to the negative electrode signal and each reference signal.

[0049] The negative reference potential represents the potential difference between the negative signal of the negative electrode and the reference signal collected in the detection area set on the positive electrode. The negative signal collected on the negative electrode is subtracted from the reference signal collected in the detection area, that is, the reference signal is subtracted from the negative signal, and the negative reference potential corresponding to the detection area is determined according to the difference between the negative signal and the reference signal.

[0050] It can be understood that in principle, the detection area can be set on both the positive electrode and the negative electrode of the battery. However, since lithium deposition is prone to occur on the negative electrode, in order to avoid setting the detection area on the negative electrode affecting the collection of the negative electrode signal, the detection area is set on the positive electrode in this embodiment to ensure the accuracy of the detection.

[0051] Step 106, determining the lithium deposition state of each detection area according to each negative reference potential.

[0052] Whether lithium deposition occurs in the detection area is determined according to the negative parameter potential corresponding to each detection area. For example, if the negative parameter potential of a detection area is greater than the preset potential value, it is judged that the detection area is normal and there is no lithium deposition; if the negative parameter potential of a detection area is less than the preset potential value, it is judged that lithium deposition occurs in the detection area.

[0053] For example, the preset potential value may be zero volts, that is, when the voltage value corresponding to the negative reference potential is less than zero volts, it is determined that lithium deposition occurs in the target battery, and when the voltage value corresponding to the negative reference potential is greater than zero volts, it is determined that lithium deposition does not occur in the target battery. Furthermore, in order to ensure the reliability of the detection, multiple parallel samples are usually tested simultaneously to determine the lithium deposition state of the battery.

[0054] In the above-mentioned battery lithium plating detection method, multiple detection areas are first set on the positive electrode of the target battery, and the reference signals corresponding to each detection area are collected. Among them, the detection area includes the electrode center detection area and the electrode edge detection area of ​​the positive electrode, and the electrode edge detection area is set to avoid the thinning area and the pole ear area of ​​the battery. Then the negative electrode signal of the target battery at the negative electrode is collected, and the negative reference potential corresponding to each detection area is determined according to the negative electrode signal and each reference signal. And finally, the lithium plating state of each detection area is determined according to each negative reference potential. The battery lithium plating detection method disclosed in this embodiment sets the detection area on the positive electrode of the target battery, and collects the potential signals of each detection area of ​​the positive electrode, and the potential signal of the negative electrode, and then determines the negative reference potential of different detection areas, so as to judge the lithium plating state of each detection area. The battery lithium plating detection method disclosed in the present invention can detect the specific lithium plating position of the target battery in real time, no longer sticking to the disassembly result of the battery, and greatly improves the lithium plating detection efficiency of the battery. The detection method disclosed in the present invention can timely improve and upgrade the battery according to the detected lithium plating state during battery design, and has high reliability.

[0055] In an exemplary embodiment, in step 102, multiple detection areas are set on the positive electrode plate of the target battery, including: if the target battery is a wound battery, a plate center detection area is set in the plate center area of ​​the positive electrode plate, and a plate edge detection area is set in the bottom edge area of ​​the positive electrode plate, the top edge area of ​​the positive electrode plate, and the R-corner edge area of ​​the positive electrode plate; if the target battery is a stacked battery, a plate center detection area is set in the plate center area of ​​the positive electrode plate, and a plate edge detection area is set in the bottom edge area of ​​the positive electrode plate and the top edge area of ​​the positive electrode plate; wherein the top edge area of ​​the positive electrode plate corresponds to the position of the pole ear, and does not include the thinning area of ​​the positive electrode plate.

[0056] This embodiment sets different detection areas according to different battery designs, and determines the detection area at the position where the battery is prone to lithium deposition. Without considering the uncontrollable factors in the battery manufacturing and testing process, lithium deposition usually occurs in the center and edge areas of the electrode plate. As mentioned above, although the thinning area is at the top edge of the electrode plate, the surface density of the thinning area fluctuates greatly, which may lead to inaccurate battery lithium deposition detection results. The insufficient current capacity of the pole lug area may also affect the lithium deposition detection in the pole lug area. Therefore, the pole piece edge detection area needs to be set away from the thinning area and the pole lug area to improve the accuracy and reliability of lithium deposition detection.

[0057] Specifically, for wound batteries, the focus of lithium plating detection is on the large surface and R corner of the battery. The large surface includes the large surface center area, the large surface bottom edge area and the large surface top edge area, and the large surface top edge area corresponds to the pole ear setting. In addition, the pole piece edge detection area needs to avoid the pole piece thinning area to ensure the reliability of the test results. For stacked batteries, lithium plating detection is mainly carried out on the large surface, because stacked batteries do not include R corners, and the large surface includes the large surface center area, the large surface bottom edge area and the large surface top edge area. Similarly, the large surface top edge area corresponds to the pole ear setting, and the pole piece edge detection area also needs to avoid the pole piece thinning area to ensure the reliability of the test results.

[0058] Please refer to Figure 2 The schematic diagram of the detection area shown in FIG. 1 shows that the light shaded portion is the positive electrode of the target battery. In this embodiment, the electrode center detection area is set at the electrode center area of ​​the positive electrode, and the electrode edge detection area is set at the bottom edge area of ​​the positive electrode, the top edge area of ​​the positive electrode, and the R-angle edge area, and the top edge area of ​​the positive electrode corresponds to the pole ear; in addition, the pole edge detection area avoids the pole thinning area and the pole ear area.

[0059] like Figure 2 As shown, the dark shaded part represents multiple detection areas set in this embodiment. In order to facilitate the determination of the setting position of the detection area, this embodiment constructs a two-dimensional coordinate system on the plane where the positive electrode sheet is located, and describes based on the two-dimensional coordinate system. Figure 2 The two-dimensional coordinate system shown has the center of the positive electrode as the origin, the horizontal direction as the first coordinate axis X-axis, and the vertical direction as the second coordinate axis Y-axis.

[0060] The detection area is set according to the constructed two-dimensional coordinate system, and the set detection area includes a pole piece center detection area set at the pole piece center of the positive pole piece, and a pole piece edge detection area set at the bottom edge area of ​​the positive pole piece, the top edge area of ​​the positive pole piece, and the R-corner edge area of ​​the positive pole piece.

[0061] The center of the positive electrode, that is, the origin of the two-dimensional coordinate system, is used as the center of the circle, and the first preset value is used as the radius to set a circular detection area. The circular detection area is the detection area at the center of the electrode, and setting the circular detection area with the first preset value as the radius can improve the accuracy of lithium deposition detection.

[0062] Along the negative Y-axis direction, a semicircular detection area with a second preset value as a radius is set at the bottom edge of the positive electrode sheet, and the semicircular detection area is the electrode edge detection area of ​​the bottom edge area of ​​the positive electrode sheet. The detection area of ​​the bottom edge area is set with the second preset value as a radius to improve the accuracy of lithium deposition detection.

[0063] Along the positive Y-axis direction, a pole piece edge detection area of ​​the top edge region of the positive pole piece is set at a third preset value away from the top edge of the positive pole piece, and the detection area of ​​the top edge region corresponds to the pole ear setting.

[0064] A pole piece edge detection area of ​​the R angle edge area is set at the R angle of the positive pole piece along the positive Y-axis direction at a fourth preset value away from the top edge of the positive pole piece.

[0065] In order to avoid the possibility that the detection area is too small and may cause deviation in the detection result, a circular detection area is set at the center of the positive electrode, and a semicircular detection area is set at the bottom edge area of ​​the positive electrode to improve the accuracy of the detection. At the same time, due to the tension at the R corner of the wound battery, the operability of the reference electrode arrangement at the R corner is relatively small, and the deeper the position of the reference electrode introduced at the R corner, the greater the polarization will be during the battery charging and discharging process, so the edge detection area of ​​the electrode at the R corner is relatively small. In addition, the edge detection area of ​​the electrode at the top edge of the positive electrode corresponds to the battery's pole ear setting and is located directly below the pole ear. The operating space for introducing the reference electrode in the edge detection area of ​​the electrode is limited, and it is necessary to avoid the thinning area of ​​the electrode, so the edge detection area of ​​the electrode at the top edge of the positive electrode is also relatively small.

[0066] The aforementioned electrode edge detection areas set in the top edge area and the R-angle edge area of ​​the electrode sheet have avoided the thinning area of ​​the positive electrode sheet, avoiding the uncertainty caused by the fluctuation of the surface density of the thinning area. At the same time, the electrode edge detection areas set in the top edge area and the R-angle edge area have also avoided the tab area of ​​the positive electrode sheet, thus avoiding the impact that may be caused by insufficient tab overcurrent capacity.

[0067] Exemplarily, the first preset value, the second preset value, and the third preset value may be 20 mm, and the fourth preset value may be 15 mm.

[0068] It can be understood that the detection area setting in the above example is the area in the battery where lithium deposition is more likely to occur, determined based on historical disassembly data. The detection area of ​​this embodiment can also be set at other positions of the positive electrode plate to improve the reliability of lithium deposition detection.

[0069] In one embodiment, the regional potential signal corresponding to each detection area is collected, including: setting a reference electrode in each detection area, setting an insulating film between the reference electrode and the positive electrode plate; collecting the potential signal of each reference electrode, and using the potential signal of each reference electrode as a reference signal.

[0070] The reference electrode is an electrode used as a reference in the experiment. In this embodiment, a reference electrode is set on the positive electrode plate, and the reference signal of the reference electrode and the negative electrode signal of the negative electrode are respectively collected, and the negative electrode signal is subtracted from the reference signal to obtain a negative reference potential, and then the lithium deposition state of the battery is determined by the negative reference potential. An insulating film is provided between the reference electrode and the positive electrode plate. Exemplarily, the reference electrode can be a copper wire as a substrate, which is artificially implanted into the battery, and a lithium layer of a certain thickness is deposited on the copper wire after implantation into the battery to obtain the reference electrode.

[0071] In one embodiment, collecting the potential signal of each reference electrode includes: acquiring different charging strategies; for each detection area, collecting the detection signal of the detection area under different charging strategies; and determining the reference signal according to each detection signal.

[0072] It is understandable that different battery systems have different fast charging capabilities, so different charging strategies are required. In addition, the charging strategies for batteries at different temperatures are also different. Therefore, it is necessary to collect the detection signals corresponding to each detection area of ​​the target battery under different charging strategies to comprehensively evaluate the fast charging capability of each detection area. Different charging strategies can be different charging parameters such as charging capacity, charging current, charging voltage, charging rate, and charging temperature. The target battery is charged based on different charging strategies, and the detection signals corresponding to each detection area of ​​the target battery under different charging strategies are collected, and then the reference signals corresponding to each detection area are obtained based on multiple detection signals. In some implementations, different charging instructions can be written in the battery management system to obtain different charging strategies.

[0073] Exemplarily, in the fast charging mode, the first detection signal of each detection area is collected at a first time interval, and the reference signal in the fast charging mode is obtained according to each first detection signal. Then, in the slow charging mode, the second detection signal of each detection area is collected at a second time interval, and the detection signal in the slow charging mode is obtained according to each second detection signal. This embodiment performs lithium plating detection through different charging strategies, so that the corresponding battery lithium plating state under different charging strategies can be determined, and then the battery risk corresponding to different charging strategies can be determined.

[0074] In one embodiment, the method further includes: acquiring a risk assessment model, inputting the lithium deposition state corresponding to each detection area into the risk assessment model, and obtaining a risk assessment result of the target battery.

[0075] In combination with the lithium deposition status determined in each detection area in the aforementioned embodiment, a risk assessment can be performed on the target battery to determine the impact of lithium deposition in each detection area on the overall battery status. For example, if lithium deposition is detected in the center area of ​​the target battery's pole piece, the target battery may be at risk of battery expansion; if lithium deposition is detected in the top edge area of ​​the target battery's pole piece, the target battery may be at risk of battery short circuit; if lithium deposition is detected in the R-corner edge area of ​​the target battery, the target battery may be at risk of rapid battery failure; if lithium deposition is detected in the bottom edge area of ​​the target battery's pole piece, the target battery may be at risk of slow battery failure.

[0076] The risk assessment model is based on a machine learning model and is trained and constructed based on historical battery lithium deposition detection data and battery risks. This embodiment uses a machine learning model to obtain the common characteristics of the lithium deposition status of different battery detection areas and the possible battery risks, which has high reliability and a wide range of applications.

[0077] In some other embodiments, the risk assessment results output by the risk assessment model can also be divided into risk levels, the lithium deposition state of the target battery can be associated with the risk level of the target battery, and the impact level of the lithium deposition state of each detection area on the battery performance or safety risk can be evaluated.

[0078] In a further embodiment, the method further includes: acquiring historical data, and determining the lithium plating status and battery risk of each detection area based on the historical data; wherein the historical data includes historical detection data or historical disassembly data; and obtaining a risk assessment model based on the lithium plating status and battery risk training.

[0079] In order to improve the reliability of the risk assessment model, in addition to model training based on historical test data, the batteries tested in the past can also be disassembled to determine the actual lithium deposition state of the batteries after disassembly, and combined with the detected negative parameter potential to obtain historical disassembly data, so as to train the risk assessment model based on historical disassembly data and historical test data to improve the reliability of the risk assessment model. This provides an initial basis for battery design and improvement, and no longer sticks to the battery disassembly results. It can also accurately detect the specific battery lithium deposition area and adjust the battery design in a timely manner.

[0080] In a specific embodiment, Figure 3 As shown, a battery lithium deposition detection method is proposed, and the method includes the following steps 302 to 306. Among them:

[0081] Step 302, determine the battery type of the target battery, set multiple detection areas on the positive electrode plate of the target battery according to the battery type, set a reference electrode in each detection area, and collect the potential signal of each reference electrode.

[0082] like Figure 2 As shown, this embodiment takes a wound battery as an example, and the detection areas are respectively set in the electrode center detection area set in the center area of ​​the positive electrode sheet, and the electrode edge detection area set in the top edge area of ​​the positive electrode sheet, the bottom edge area of ​​the positive electrode sheet, and the R angle edge area of ​​the positive electrode sheet. Among them, the top edge area and the R angle edge area have avoided the electrode thinning area and the pole ear area. Reference electrodes are set in each detection area to collect the potential signal of each reference electrode.

[0083] Step 304 , collecting the negative electrode signal of the target battery at the negative electrode plate, and determining the negative reference potential corresponding to each detection area according to the negative electrode signal and each reference signal.

[0084] The negative electrode signal collected on the negative electrode piece is subtracted from the reference signal of the detection area, that is, the reference signal is subtracted from the negative electrode signal to obtain the negative reference potential corresponding to each detection area.

[0085] In some other implementations, detection signals at different charging capacities, charging currents, charging voltages, charging rates or charging temperatures can be collected to implement battery lithium plating detection under different charging strategies, and then the battery risks under different charging strategies can be judged based on the battery lithium plating detection results under different charging strategies.

[0086] Step 306, determining the lithium deposition state of each detection area according to each negative reference potential.

[0087] If the negative parameter potential of a certain detection area is greater than zero, it is judged that the detection area is normal and there is no lithium deposition phenomenon. If the negative parameter potential of a certain detection area is less than zero, it is judged that there is lithium deposition phenomenon in the detection area.

[0088] Step 308, obtaining a risk assessment model, inputting the lithium deposition state corresponding to each detection area into the risk assessment model, and obtaining a risk assessment result of the target battery.

[0089] Combined with the lithium deposition status corresponding to each detection area, the target battery is risk assessed through the risk assessment model to predict the battery risk of the target battery. For example, if lithium deposition is detected in the center area of ​​the target battery's pole piece, the target battery may have a risk of battery expansion; if lithium deposition is detected in the top edge area of ​​the target battery's pole piece, the target battery may have a risk of battery short circuit; if lithium deposition is detected in the R-corner edge area of ​​the target battery, the target battery may have a risk of rapid battery failure; if lithium deposition is detected in the bottom edge area of ​​the target battery's pole piece, the target battery may have a risk of slow battery failure.

[0090] This embodiment can process and analyze the data based on the potential signal source collected in different detection areas of the battery to simultaneously determine whether lithium deposition occurs in multiple detection areas of the battery, and then lock the specific lithium deposition location of the target battery in real time based on the judgment result. This embodiment can also automatically train the potential data at different locations of the target battery through a trained risk assessment model to assess the lithium deposition risk at different locations and the impact on battery performance and safety issues.

[0091] This embodiment can effectively obtain the lithium plating conditions of the target battery at different positions after a series of working conditions, and evaluate the possible risks of the target battery in the future, providing an initial basis for the design and improvement of the battery, and is no longer restricted to the disassembly results of the battery, with good reliability and high detection efficiency.

[0092] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0093] Based on the same inventive concept, the embodiment of the present application also provides a battery lithium deposition detection device for implementing the battery lithium deposition detection method involved above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations in one or more battery lithium deposition detection device embodiments provided below can refer to the limitations of the battery lithium deposition detection method above, and will not be repeated here.

[0094] In an exemplary embodiment, Figure 4 As shown, a battery lithium deposition detection device is provided, including: a region determination module 402, a data acquisition module 404 and a detection module 406, wherein:

[0095] The region determination module 402 is configured to: set a plurality of detection regions on the positive electrode sheet of the target battery, and collect reference signals corresponding to the detection regions; wherein the detection regions include a center detection region and an edge detection region of the positive electrode sheet;

[0096] The data acquisition module 404 is configured to: acquire the negative electrode signal of the target battery at the negative electrode plate, and determine the negative reference potential corresponding to each detection area according to the negative electrode signal and each reference signal;

[0097] The detection module 406 is configured to determine the lithium deposition state of each detection area according to each negative reference potential.

[0098] In one embodiment, the area determination module 402 is further configured as follows: if the target battery is a wound battery, a pole piece center detection area is set in the pole piece center area of ​​the positive pole piece, and a pole piece edge detection area is set in the bottom edge area of ​​the positive pole piece, the top edge area of ​​the positive pole piece, and the R-corner edge area of ​​the positive pole piece; if the target battery is a stacked battery, a pole piece center detection area is set in the pole piece center area of ​​the positive pole piece, and a pole piece edge detection area is set in the bottom edge area of ​​the positive pole piece and the top edge area of ​​the positive pole piece; wherein the top edge area of ​​the positive pole piece corresponds to the position of the pole ear, and does not include the thinning area of ​​the positive pole piece.

[0099] In one embodiment, the data acquisition module 404 is further configured to: set a reference electrode in each detection area, and set an insulating film between the reference electrode and the positive electrode; collect the potential signal of each reference electrode, and use the potential signal of each reference electrode as a reference signal.

[0100] In one embodiment, the data acquisition module 404 is further configured to: acquire different charging strategies; for each detection area, acquire detection signals of the detection area under different charging strategies; and determine a reference signal according to each detection signal.

[0101] In one embodiment, the device is further configured to: obtain a risk assessment model, input the lithium plating state corresponding to each detection area into the risk assessment model, and obtain a risk assessment result of the target battery.

[0102] In one embodiment, the device is further configured to: obtain historical data, determine the lithium plating status and battery risk of each detection area based on the historical data; wherein the historical data includes historical detection data or historical disassembly data; and obtain a risk assessment model based on the lithium plating status and battery risk training.

[0103] Each module in the above-mentioned battery lithium deposition detection device can be implemented in whole or in part by software, hardware and a combination thereof. Each of the above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to each of the above modules.

[0104] In an exemplary embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as shown in FIG. Figure 5As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. Among them, the processor, the memory and the input / output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a battery lithium deposition detection method is implemented.

[0105] Those skilled in the art will understand that Figure 5 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0106] In an exemplary embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0107] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0108] In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0109] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0110] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0111] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the present application. It should be noted that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A battery lithium deposition detection method, characterized in that: The method comprises: A plurality of detection areas are set on the positive electrode sheet of the target battery, and reference signals corresponding to the detection areas are collected; wherein the detection areas include a center detection area and an edge detection area of ​​the positive electrode sheet; Collecting the negative electrode signal of the target battery at the negative electrode plate, and determining the negative reference potential corresponding to each of the detection areas according to the negative electrode signal and each of the reference signals; The lithium deposition state of each of the detection areas is determined according to each of the negative reference potentials.

2. The method according to claim 1, characterized in that The method of setting a plurality of detection areas on the positive electrode sheet of the target battery includes: If the target battery is a wound battery, the electrode sheet center detection area is set in the electrode sheet center area of ​​the positive electrode sheet, and the electrode sheet edge detection area is set in the bottom edge area of ​​the positive electrode sheet, the top edge area of ​​the positive electrode sheet, and the R corner edge area of ​​the positive electrode sheet; If the target battery is a laminated battery, the electrode sheet center detection area is set in the electrode sheet center area of ​​the positive electrode sheet, and the electrode sheet edge detection area is set in the bottom edge area of ​​the positive electrode sheet and the top edge area of ​​the positive electrode sheet; The top edge area of ​​the positive electrode sheet corresponds to the position of the electrode lug and does not include the thinned area of ​​the positive electrode sheet.

3. The method according to claim 1, characterized in that The collecting of reference signals corresponding to the detection areas includes: A reference electrode is provided in each of the detection areas, and an insulating film is provided between the reference electrode and the positive electrode sheet; The potential signal of each reference electrode is collected, and the potential signal of each reference electrode is used as the reference signal.

4. The method according to claim 3, characterized in that The collecting of the potential signal of each reference electrode comprises: Get different charging strategies; For each detection area, detection signals of the detection area under different charging strategies are collected; and the reference signal is determined according to each of the detection signals.

5. The method according to claim 1, characterized in that The method further comprises: A risk assessment model is obtained, and the lithium plating state corresponding to each of the detection areas is input into the risk assessment model to obtain a risk assessment result of the target battery.

6. The method according to claim 5, characterized in that The method further comprises: Acquire historical data, and determine the lithium plating status and battery risk of each of the detection areas according to the historical data; wherein the historical data includes historical detection data or historical disassembly data; The risk assessment model is obtained according to the lithium plating state and the battery risk training.

7. A battery lithium deposition detection device, characterized in that: The device comprises: The area determination module is configured to: set a plurality of detection areas on the positive electrode sheet of the target battery, and collect reference signals corresponding to the detection areas; wherein the detection areas include a center detection area and an edge detection area of ​​the positive electrode sheet; The data acquisition module is configured to: collect the negative electrode signal of the target battery at the negative electrode plate, and determine the negative reference potential corresponding to each of the detection areas according to the negative electrode signal and each of the reference signals; The detection module is configured to determine the lithium deposition state of each of the detection areas according to each of the negative reference potentials.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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