Accelerated attenuation identification method, device and equipment of lithium ion battery and medium

Abstract

The invention relates to the technical field of batteries, particularly provides an accelerated attenuation identification method and device of a lithium ion battery, equipment and a medium, and aims to solve the technical problem of how to accurately identify accelerated attenuation of capacity in the cycle aging process of the lithium ion battery. In order to achieve the purpose, the method comprises the steps that when the lithium ion battery is subjected to charge-discharge circulation, voltage data and capacity data in the charging process are obtained; based on the voltage data and the capacity data corresponding to different loop numbers, acquiring charging voltage platform change data; and determining whether the lithium ion battery accelerates attenuation based on the charging voltage platform change data. Through the implementation mode, whether the lithium ion battery has accelerated attenuation caused by lithium precipitation or not can be accurately identified through data analysis in advance, whether the risk of diving exists in the later period of circulation or not is determined, the normal circulation process of the battery does not need to be changed, and a result can be obtained directly through analysis of circulation data; the method is suitable for lithium ion batteries with different systems and different formulas.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a method, device, equipment and medium for identifying accelerated decay of a lithium-ion battery. Background Art

[0002] Lithium-ion batteries have been widely used in electric vehicles and energy storage due to their high energy density and long cycle life. However, during the cycle of lithium-ion batteries, the reduction of electrolyte content, the thickening of the negative electrode solid electrolyte interface (SEI), the increase of by-products, the reduction of negative electrode porosity, etc. will lead to internal polarization and increased impedance of the battery, thus shortening the battery life. Among lithium-ion batteries, the positive electrode of lithium iron phosphate batteries uses lithium iron phosphate, which is usually more stable and does not suffer from the serious metal dissolution like ternary lithium batteries. Its negative electrode is also relatively stable. In general, the loss of positive and negative electrode materials of lithium iron phosphate batteries is not the main reason for its capacity loss. Its capacity reduction is usually caused by the loss of active lithium. The loss of active lithium will lead to lithium precipitation, which will cause a serious deterioration of the battery capacity.

[0003] At present, lithium iron phosphate batteries have good stability and long cycle life. It is impossible to obtain data on their actual cycle to the aging stage in a short period of time, and it is impossible to know their cycle life, so their cycle life is usually obtained by life prediction. However, as the battery ages, lithium plating on the negative electrode surface consumes a large amount of active lithium, and uniform lithium plating will produce irreversible dead lithium, causing a large amount of irreversible capacity loss in the battery, resulting in a sudden increase or even a drop in the decay rate of the battery with uniform capacity decay (the capacity drops sharply in a short period of time), and the original life of the battery cannot be reached. In addition, as lithium plating becomes more serious, the precipitated lithium metal may also form dendrites, and the resulting dendrites will continue to grow to the other side of the diaphragm, eventually inducing a short circuit in the battery, leading to dangerous accidents. Therefore, it is necessary to predict the accelerated decay caused by lithium plating, and lithium plating is usually related to many factors. Existing methods cannot accurately identify the risks of lithium plating, accelerated decay, and capacity diving of batteries under different cycle conditions.

[0004] Accordingly, the art needs a new accelerated decay identification solution for lithium-ion batteries to solve the above problems. Summary of the invention

[0005] In order to overcome the above-mentioned defects, the present application is proposed to provide a method, device, equipment and medium for identifying accelerated decay of lithium-ion batteries that solves or at least partially solves the technical problem of how to accurately identify the accelerated decay of capacity during the cycle aging process of lithium-ion batteries.

[0006] In a first aspect, a method for identifying accelerated decay of a lithium-ion battery is provided, the method comprising:

[0007] When the lithium-ion battery is charged and discharged, the voltage data and capacity data during the charging process are obtained;

[0008] Based on the voltage data and capacity data corresponding to different numbers of cycles, acquiring charging voltage platform change data;

[0009] Whether the lithium-ion battery will accelerate decay is determined based on the charging voltage platform change data.

[0010] In a technical solution of the above-mentioned method for identifying accelerated attenuation of a lithium-ion battery, obtaining charging voltage platform change data based on the voltage data and capacity data corresponding to different numbers of cycles includes:

[0011] Obtaining the relationship between the voltage data and the capacity data corresponding to the different numbers of cycles;

[0012] Based on the relationship, the charging voltage platform values ​​corresponding to the different numbers of cycles are obtained;

[0013] Based on the charging voltage platform values ​​corresponding to the different numbers of cycles, the charging voltage platform change data is obtained.

[0014] In a technical solution of the above-mentioned method for identifying accelerated decay of a lithium-ion battery, determining whether the lithium-ion battery will decay rapidly based on the charging voltage platform change data includes:

[0015] Obtaining the difference between the charging voltage platform value corresponding to the subsequent cycle number and the charging voltage platform value corresponding to the previous cycle number;

[0016] Determining whether the difference exceeds a preset threshold;

[0017] If so, it is determined that the lithium-ion battery will decay at an accelerated rate; otherwise, it is determined that the lithium-ion battery will not decay at an accelerated rate.

[0018] In a technical solution of the above-mentioned method for identifying accelerated degradation of lithium-ion batteries, the method further includes:

[0019] Performing differential processing on the voltage data and the capacity data to obtain a differential curve of capacity and voltage;

[0020] Obtaining a phase change voltage value in the differential curve;

[0021] Whether the lithium-ion battery will accelerate degradation is determined based on the phase change voltage value.

[0022] In a technical solution of the above-mentioned method for identifying accelerated decay of a lithium-ion battery, determining whether the lithium-ion battery will decay rapidly based on the phase change voltage value includes:

[0023] Obtain the differential curves of capacity and voltage corresponding to different numbers of cycles;

[0024] Obtaining full-battery phase change voltage values ​​corresponding to different cycle numbers based on the differential curve;

[0025] Determine whether the full battery phase change voltage value corresponding to the subsequent cycle number is greater than the full battery phase change voltage value corresponding to the previous cycle number;

[0026] If so, it is determined that the lithium-ion battery will decay at an accelerated rate; otherwise, it is determined that the lithium-ion battery will not decay at an accelerated rate.

[0027] In a technical solution of the above-mentioned method for identifying accelerated decay of a lithium-ion battery, determining whether the lithium-ion battery will decay rapidly based on the phase change voltage value further includes: Obtain the differential curves of capacity and voltage corresponding to different numbers of cycles;

[0028] Obtaining negative electrode phase change voltage values ​​corresponding to different cycle numbers based on the differential curve;

[0029] Determine whether the negative electrode phase change voltage value corresponding to the subsequent cycle number is greater than the negative electrode phase change voltage value corresponding to the previous cycle number;

[0030] If so, it is determined that the lithium-ion battery will decay at an accelerated rate; otherwise, it is determined that the lithium-ion battery will not decay at an accelerated rate.

[0031] In one technical solution of the above-mentioned method for identifying accelerated attenuation of a lithium-ion battery, the lithium-ion battery is charged and discharged for cycling, including:

[0032] Controlling the lithium-ion battery to perform charge and discharge cycles under preset conditions;

[0033] Wherein, the preset conditions include a preset charging current, a preset discharging current, a preset charging cut-off voltage and a preset discharging cut-off voltage.

[0034] In a second aspect, the present application provides a device for identifying accelerated decay of a lithium-ion battery, the device comprising:

[0035] A first acquisition module, configured to acquire voltage data and capacity data of the lithium-ion battery during a charging process when the lithium-ion battery undergoes a charge and discharge cycle;

[0036] A second acquisition module is configured to acquire charging voltage platform change data based on the voltage data and capacity data corresponding to different numbers of cycles;

[0037] A judgment module is configured to determine whether the lithium-ion battery will accelerate decay based on the charging voltage platform change data.

[0038] In a third aspect, an electronic device is provided, comprising a processor and a memory, wherein the memory is suitable for storing a plurality of program codes, and the program codes are suitable for being loaded and run by the processor to execute the accelerated degradation identification method of a lithium-ion battery described in any one of the technical solutions of the above-mentioned accelerated degradation identification method of a lithium-ion battery.

[0039] In a fourth aspect, a computer-readable storage medium is provided, in which a plurality of program codes are stored, wherein the program codes are suitable for being loaded and run by a processor to execute the accelerated degradation identification method for lithium-ion batteries described in any one of the technical solutions of the above-mentioned accelerated degradation identification method for lithium-ion batteries.

[0040] The above one or more technical solutions of this application have at least one or more of the following Beneficial effects:

[0041] In the technical solution of the present application, when the lithium-ion battery is charged and discharged, the voltage data and capacity data during the charging process can be obtained, and the charging voltage platform change data can be obtained based on the voltage data and capacity data corresponding to different cycle numbers, and whether the lithium-ion battery will accelerate decay can be determined based on the charging voltage platform change data. Through the above implementation, it is possible to accurately identify whether the lithium-ion battery has accelerated decay caused by lithium plating through data analysis in advance, and determine whether there is a risk of diving in the later stage of the cycle, and there is no need to disassemble the battery for analysis, no need to implant additional reference electrodes, and no need to change the normal cycle process of the battery. The results can be obtained directly by analyzing the cycle data, which is suitable for lithium-ion batteries of different systems and different formulas. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The disclosure of the present application will become easier to understand with reference to the accompanying drawings. It is easy for those skilled in the art to understand that these drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present application. Among them:

[0043] Figure 1 is a schematic flow chart of the main steps of a method according to an embodiment of the present application;

[0044] Figure 2 1 is a schematic diagram of a curve showing the change of voltage data and capacity data of a lithium-ion battery in Example 1 of the present application at different cycle numbers;

[0045] Figure 3 1 is a schematic diagram of a change curve of voltage data and capacity data corresponding to different cycle numbers of the lithium-ion battery in Example 2 of the present application;

[0046] Figure 41 is a schematic diagram of a curve showing the change of voltage data and capacity data of a lithium-ion battery in Example 3 of the present application at different cycle numbers;

[0047] Figure 5 This is a schematic diagram of the interface disassembly of the lithium-ion battery in Example 1 of this application;

[0048] Figure 6 This is a schematic diagram of the interface disassembly of the lithium-ion battery in Example 2 of this application;

[0049] Figure 7 This is a schematic diagram of the interface disassembly of the lithium-ion battery of Case 3 of this application;

[0050] Figure 8 is a schematic flow chart of the main steps of a method for identifying accelerated degradation of a lithium-ion battery according to another embodiment of the present application;

[0051] Fig. 9 is a schematic diagram of the relationship between voltage data and capacity data of a lithium-ion battery according to an embodiment of the present application;

[0052] Fig.10 is a schematic diagram of a differential curve of capacity and voltage of a lithium-ion battery according to an embodiment of the present application;

[0053] Fig.11 1 is a schematic diagram of the differential curve of capacity and voltage corresponding to different cycle numbers of the lithium-ion battery in Example 1 of the present application;

[0054] Fig.12 1 is a schematic diagram of differential curves of capacity and voltage corresponding to different numbers of cycles of the lithium-ion battery in Example 2 of the present application;

[0055] Fig.13 1 is a schematic diagram of differential curves of capacity and voltage corresponding to different numbers of cycles of the lithium-ion battery in Example 3 of the present application;

[0056] Fig.14 1 is a schematic diagram of the relationship between the SOH and the number of cycles of the lithium-ion battery in Example 1 of the present application;

[0057] Fig.15 1 is a graph showing the relationship between the SOH and the number of cycles of the lithium-ion battery in Example 2 of the present application;

[0058] Fig.16 1 is a graph showing the relationship between the SOH and the number of cycles of the lithium-ion battery in Example 3 of the present application;

[0059] Fig.17 is a main structural block diagram of an accelerated decay identification device according to an embodiment of the present application;

[0060] Fig.18It is a schematic diagram of the main structure of an electronic device according to an embodiment of the present application.

[0061] List of reference numerals:

[0062] 1701: first acquisition module; 1702: second acquisition module; 1703: determination module; 1801: processor; 1802: memory. DETAILED DESCRIPTION

[0063] Some embodiments of the present application are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present application and are not intended to limit the protection scope of the present application.

[0064] In the description of this application, "module" and "processor" may include hardware, software or a combination of the two. A module may include hardware circuits, various suitable sensors, communication ports, memories, and may also include software parts, such as program codes, or a combination of software and hardware. The processor may be a central processing unit, a microprocessor, an image processor, a digital signal processor or any other suitable processor. The processor has data and / or signal processing functions. The processor may be implemented in software, hardware or a combination of the two. Non-temporary computer-readable storage media include any suitable media that can store program codes, such as disks, hard disks, optical disks, flash memory, read-only memory, random access memory, etc.

[0065] The term "A and / or B" means all possible combinations of A and B, such as only A, only B, or A and B. The term "at least one of A or B" or "at least one of A and B" has a similar meaning to "A and / or B" and may include only A, only B, or A and B. The singular forms "a", "the" and "the" may also include plural forms.

[0066] Here we first explain some terms involved in this application.

[0067] Lithium deposition: During the battery charging and discharging process, lithium ions are abnormally deposited on the surface of the negative electrode.

[0068] Polarization: The phenomenon that the potential of the electrode deviates from its equilibrium potential when no current flows during the charging and discharging process of the battery.

[0069] Back-intercalation: The process by which lithium ions are reinserted into electrode materials under specific conditions.

[0070] Stripping reaction: When the battery is discharged with a small current, some lithium ions originally embedded in the negative electrode material are separated from the negative electrode material.

[0071] Reference electrode (tertiary electrode): A specially treated electrode used to measure the potential change of the negative electrode of the battery and serve as a reference standard for determining whether lithium deposition occurs.

[0072] Phase change: The structural phase transformation of the negative electrode material of the battery during the lithium insertion process. When the battery is charged, lithium ions are released from the positive electrode and migrate to the negative electrode, and then embedded in the interlayer structure of the negative electrode material. As the lithium ions are continuously embedded, the crystal structure of the negative electrode material will change accordingly. This process is called phase change.

[0073] Phase change voltage: The voltage value corresponding to the phase change of the negative electrode material during the battery charging process.

[0074] As described in the background technology, lithium-ion batteries have been widely used in electric vehicles and energy storage fields due to their high energy density and long cycle life. However, during the cycle of lithium-ion batteries, the reduction of electrolyte content, the thickening of negative electrode SEI, the increase of byproducts, the reduction of negative electrode porosity, etc. will lead to internal polarization of the battery and increase of impedance, thus shortening the battery life.

[0075] Among lithium-ion batteries, the positive electrode of lithium iron phosphate batteries uses lithium iron phosphate, which is usually more stable and does not have the serious metal dissolution like ternary lithium batteries. Its negative electrode is also relatively stable. In general, the loss of positive and negative electrode materials of lithium iron phosphate batteries is not the main reason for its capacity loss. Its capacity reduction is usually caused by the loss of active lithium, which is caused by the inactivation of positive and negative electrode materials, which makes some active lithium unable to escape, the formation of CEI on the surface of positive electrode materials or SEI on the surface of negative electrode materials, the increase of polarization, which makes some active lithium unable to play a role, and the consumption of side reactions inside the battery. The loss of active lithium will lead to lithium precipitation, which will cause serious deterioration of the battery.

[0076] At present, lithium iron phosphate batteries have good stability and long cycle life. It is impossible to obtain data on their actual cycle to the aging stage in a short period of time, and it is impossible to know their cycle life, so their cycle life is usually obtained by relying on life prediction. However, as the battery ages, lithium deposition on the surface of the negative electrode consumes a large amount of active lithium, and uniform lithium deposition will produce irreversible dead lithium, causing a large amount of irreversible capacity loss in the battery, resulting in a sudden increase or even a drop in the decay rate of the battery with uniform capacity decay, and the original life of the battery cannot be achieved. In addition, as lithium deposition becomes more serious, the precipitated lithium metal may also form dendrites, and the resulting dendrites will continue to grow to the other side of the diaphragm, eventually inducing a short circuit in the battery, leading to dangerous accidents. Therefore, it is necessary to predict the accelerated decay caused by lithium deposition.

[0077] Commonly used methods for testing battery negative electrode lithium plating include the following:

[0078] 1. Use enameled wire (copper wire) plated with lithium as the reference electrode and observe the potential change of the negative electrode. When the negative electrode potential is 0, it is believed that lithium deposition begins to occur on the negative electrode surface. However, this method has certain disadvantages. It does not consider the influence of polarization. The reference electrode has a time limit. After a period of time, the lithium on the copper wire will slowly dissolve, causing the reference electrode potential to change. It is impossible to determine whether lithium deposition occurs in the battery in the later stage of the cycle.

[0079] 2. After fully charging the battery, disassemble it and observe whether lithium deposition occurs on the negative electrode surface. This method is subjective, has large errors, is inefficient, costly, and complex to operate. It is also impossible to find the exact critical point for lithium deposition, and can only simply determine whether lithium deposition occurs on the battery.

[0080] 3. Charge the battery, analyze the voltage-time differential curve in the static stage after charging, and judge whether lithium plating occurs by the voltage change caused by the reinsertion of some active lithium. This method must be added with a long static stage after charging for analysis, but the actual battery cycle test standard does not increase the static stage, so this method is not suitable for continuous analysis of continuously cycled batteries.

[0081] 4. After the battery is normally charged, the voltage data corresponding to the active lithium stripping reaction during small current discharge is used to determine whether lithium plating has occurred. The disadvantages of this method are the same as those of method 3, that is, small current discharge is not performed in the actual cycle test standard, so this method is not suitable for continuous analysis of batteries with continuous cycles.

[0082] Since lithium plating is related to many factors such as battery system design, material properties, positive and negative electrode surface density, compaction density, liquid injection volume, test rate, etc., most of the above methods cannot accurately identify the risks of lithium plating, accelerated attenuation and capacity diving of lithium-ion batteries in different cycle conditions, and it is difficult to obtain a universally applicable method.

[0083] In order to solve the above problems, the present application provides a method, device, equipment and medium for identifying accelerated decay of a lithium-ion battery.

[0084] See attached Figure 1 , Figure 1 1 is a flow chart of the main steps of a method according to an embodiment of the present application. Figure 1 As shown, the accelerated degradation identification method of a lithium-ion battery in the embodiment of the present application mainly includes the following steps S101 to S103.

[0085] Step S101: when the lithium-ion battery is undergoing a charge and discharge cycle, obtaining voltage data and capacity data during the charging process;

[0086] Step S102: acquiring charging voltage platform change data based on voltage data and capacity data corresponding to different numbers of cycles;

[0087] Among them, the charging voltage platform refers to a relatively stable voltage range in which the voltage changes with the capacity during the battery charging process.

[0088] Step S103: determining whether the lithium-ion battery will accelerate degradation based on the charging voltage platform change data.

[0089] Based on the method described in steps S101 to S103 above, it is possible to accurately identify in advance through data analysis whether the lithium-ion battery has accelerated attenuation caused by lithium plating, and determine whether there is a risk of water drop in the later stage of the cycle. There is no need to disassemble the battery for analysis, no need to additionally implant a reference electrode, and no need to change the normal cycle process of the battery. The result can be obtained directly by analyzing the cycle data, and it is suitable for lithium-ion batteries of different systems and different formulas.

[0090] The accelerated degradation identification method of the above lithium-ion battery is further described below.

[0091] In lithium-ion batteries, the positive electrode material of lithium iron phosphate batteries is lithium iron phosphate (LFP), and the negative electrode material is generally graphite (C). Among them, the positive electrode lithium iron phosphate has an olivine structure, which belongs to the orthorhombic crystal system, and the atoms are arranged in a hexagonal close-packed manner. This structure makes the lithium iron phosphate have good stability and can maintain good crystal structure integrity during the charge and discharge process, which is conducive to improving the cycle life of the battery. The graphite of the negative electrode has a complete layered crystal structure. This structure allows the graphite to accommodate lithium atoms. During the charge and discharge process, lithium ions can be embedded and removed between the graphite layers to realize the charge and discharge function of the battery.

[0092] One of the main reasons for the accelerated attenuation or even drop of LFP-C batteries is the lithium deposition of the battery, which mainly occurs in the process of lithium embedding in the negative electrode material. When the battery charging polarization increases significantly, the original normal charge and discharge balance state may be broken. For example, the internal resistance of the battery increases, the ion transmission channel is blocked, etc., which slows down the movement and embedding of lithium ions into the negative electrode material. The lithium ions that could be normally embedded cannot be embedded in time, and will be deposited on the negative electrode surface in the form of metallic lithium, resulting in lithium deposition, which leads to the accelerated attenuation of the battery capacity and a drop.

[0093] The inventors have found through a large number of experimental observations that when the charging polarization increases, the charging voltage platform will increase, and the lithium insertion voltage of the same phase change of the negative electrode material will increase. Therefore, by analyzing the changes in the charging voltage platform at different cycle stages and the voltage changes of the phase change of the negative electrode material, this application can identify whether the battery has the risk of accelerated attenuation and capacity diving caused by lithium deposition in the late cycle.

[0094] In some implementations of the above step S101, the lithium iron phosphate battery may be controlled to perform a charge and discharge cycle under preset conditions to obtain voltage data and capacity data during the charging process.

[0095] The preset conditions include a preset charging current, a preset discharging current, a preset charging cut-off voltage, a preset discharging cut-off voltage, and the like.

[0096] Specifically, the preset conditions can be designed according to the required working conditions and battery characteristics, such as setting the preset charging current between 1C and 3C (where C represents the rate capacity of the battery and 1C represents the current intensity that fully charges the battery in 1 hour), the preset discharge current between 0.1C and 0.5C, the preset charging cut-off voltage between 3.6V and 3.7V, and the preset discharge cut-off voltage between 2.0V and 2.5V, etc., which are not limited here.

[0097] Furthermore, when the battery is undergoing a charge and discharge cycle, voltage data and capacity data during the charging process can be collected.

[0098] The above is a further description of step S101 , and the following is a further description of step S102 .

[0099] In some implementations of the above step S102, based on the voltage data and capacity data corresponding to different numbers of cycles, obtaining the charging voltage platform change data may include the following steps S1021 to S1023:

[0100] Step S1021: Obtaining the relationship between voltage data and capacity data corresponding to different numbers of cycles;

[0101] During the battery charging and discharging process, since the internal electrochemical state of the battery (such as changes in the electrode material structure, changes in the electrolyte performance, etc.) will be different at different cycle numbers, the relationship between the voltage data and the capacity data at each cycle number can be obtained.

[0102] In some implementations, a linear relationship between the voltage data and the capacity data corresponding to different numbers of cycles can be obtained, such as by plotting the capacity data as the horizontal axis and the voltage data as the vertical axis to obtain a linear relationship between the voltage data and the capacity data.

[0103] In addition, the voltage data and capacity data corresponding to different numbers of cycles may be fitted to obtain a functional relationship between the voltage data and the capacity data, etc., which is not limited here.

[0104] Step S1022: obtaining charging voltage platform values ​​corresponding to different numbers of cycles based on the relationship;

[0105] During the charging process, the charging voltage will show a relatively stable voltage range as the capacity changes. The charging voltage platform value can be the middle value or average value of the voltage range, etc., which is not limited here.

[0106] Furthermore, according to the relationship between the voltage data and the capacity data, the charging voltage platform values ​​corresponding to different numbers of cycles can be obtained.

[0107] Step S1023: obtaining charging voltage platform variation data based on charging voltage platform values ​​corresponding to different numbers of cycles.

[0108] Changes in the charging voltage platform value can reflect the degree of battery aging, changes in internal structure, etc. By comparing the charging voltage platform values ​​under different cycle numbers, we can understand the performance changes of the battery during the recycling process and identify whether the battery has the risk of accelerated attenuation and capacity diving caused by lithium plating in the later stage of the cycle.

[0109] The above is a further description of step S102 , and the following is a further description of step S103 .

[0110] In some implementations of the above step S103, since the charging voltage platform will increase when the charging polarization increases, it is possible to determine whether the lithium-ion battery has the risk of accelerated attenuation in the later stage of the cycle by changing the charging voltage platform corresponding to different numbers of cycles under preset conditions.

[0111] Specifically, the difference between the charging voltage platform value corresponding to the subsequent number of cycles and the charging voltage platform value corresponding to the previous number of cycles can be obtained, and it can be determined whether the difference exceeds a preset threshold; if so, it is determined that the lithium-ion battery will accelerate decay; otherwise, it is determined that the lithium-ion battery will not accelerate decay.

[0112] There is a high degree of flexibility in the selection of the number of front cycles and the number of back cycles of the lithium-ion battery.

[0113] For example, in the early stage of lithium-ion battery use, in order to preliminarily judge the accelerated battery attenuation, the charging voltage platform values ​​of the battery after 1 cycle and 100 cycles can be compared. As the number of cycles increases, the charging voltage platform values ​​of the battery after 101 cycles, 102 cycles, etc. can be compared with the charging voltage platform value of 1 cycle in real time to understand the changing trend of the charging voltage platform value during the initial use of the battery.

[0114] After the battery has been used for a long time, in order to more accurately identify whether the lithium-ion battery has accelerated attenuation caused by lithium plating, the charging voltage platform value of the later cycle number such as 1000 cycles and 2000 cycles can be selected and compared with the charging voltage platform value of the previous cycle number, and the difference between the charging voltage platform value corresponding to the later cycle number and the charging voltage platform value corresponding to the previous cycle number can be obtained, and it can be determined whether the difference exceeds the preset threshold.

[0115] Due to different battery application scenarios, battery types and specific requirements for battery performance, the preset threshold can be set to any value greater than 0 according to the actual application scenario, and is not limited here.

[0116] Furthermore, if the difference between the charging voltage platform value corresponding to the latter number of cycles and the charging voltage platform value corresponding to the former number of cycles exceeds a preset threshold, it is determined that the lithium-ion battery will decay faster; otherwise, it is determined that the lithium-ion battery will not decay faster.

[0117] For example, the preset threshold is set to 0.1V, and the charging voltage platform value of the battery after 1 cycle is 3.4V, and the charging voltage platform value after 1000 cycles is 3.413V. At this time, the difference between the charging voltage platform values ​​of 1000 cycles and 1 cycle is 0.13V, which exceeds 0.1V. It can be considered that the lithium-ion battery has the risk of accelerated attenuation in the later stage of the cycle.

[0118] It should be pointed out that the above examples of preset thresholds and number of cycles are only for illustrative purposes. In practical applications, those skilled in the art may make settings according to specific scenarios, and no limitation is made here.

[0119] The following takes LFP-C battery as an example to further illustrate the accelerated attenuation identification method of the above lithium-ion battery.

[0120] Specifically, three preset conditions can be designed for different working conditions, and the LFP-C battery can be charged and discharged under the three preset conditions respectively. The voltage data and capacity data corresponding to different cycle numbers of the three cases are collected and plotted. The capacity data is used as the horizontal axis and the voltage data is used as the vertical axis to obtain the change curve of the voltage data and the capacity data.

[0121] See attached Figures 2 to 4 , Figure 2 1 is a schematic diagram of a curve showing the change of voltage data and capacity data of a lithium-ion battery in Example 1 of the present application at different cycle numbers; Figure 3 1 is a schematic diagram of a change curve of voltage data and capacity data corresponding to different cycle numbers of the lithium-ion battery in Example 2 of the present application; Figure 4 This is a schematic diagram of the change curve of voltage data and capacity data corresponding to different cycle numbers of the lithium-ion battery in Example 3 of this application.

[0122] like Figure 2 As shown in FIG. 1 , the voltage and capacity data corresponding to the lithium-ion battery in case 1 are collected during the charging process, when the cycle is 1, 2000, 4000, and 6000. Figure 2 It can be seen that the charging voltage platform values ​​corresponding to different cycle numbers do not change significantly. At this time, the difference between the charging voltage platform value corresponding to the later cycle number and the charging voltage platform value corresponding to the previous cycle number does not exceed the preset threshold. This means that with the increase in the number of cycles, the polarization of the battery charge does not increase significantly, so it can be determined that the battery does not have the risk of accelerated attenuation caused by lithium precipitation in the later stage of the cycle.

[0123] Similarly, if Figure 3 As shown in FIG. 1 , the voltage and capacity data corresponding to the lithium-ion battery of Case 2 are collected during the charging process, when the battery is cycled 1, 1000, and 2000 times. Figure 3 It can be seen that the battery has no risk of accelerated attenuation caused by lithium plating in the later stages of the cycle.

[0124] like Figure 4 As shown in FIG. 1 , the voltage and capacity data corresponding to the lithium-ion battery in case 1 are collected during the charging process, when the cycle is 1, 2000, 4000, and 5000. Figure 4 It can be seen that the charging voltage platform value at 5000 cycles is significantly higher than that at 1 cycle. At this time, the difference between the charging voltage platform value corresponding to the latter number of cycles and the charging voltage platform value corresponding to the former number of cycles exceeds the preset threshold. This means that as the number of cycles increases, the polarization of the battery charge increases, so it can be determined that the battery has the risk of accelerated attenuation caused by lithium precipitation in the later stage of the cycle.

[0125] Furthermore, in order to prove that the increase in the charging voltage platform will cause lithium deposition in lithium-ion batteries, thereby leading to the risk of accelerated degradation, the interfaces of the lithium-ion batteries in the above three cases were disassembled.

[0126] See attached Figures 5 to 7 , Figure 5 This is a schematic diagram of the interface disassembly of the lithium-ion battery in Example 1 of this application; Figure 6 This is a schematic diagram of the interface disassembly of the lithium-ion battery in Example 2 of this application; Figure 7 This is a schematic diagram of the interface disassembly of the lithium-ion battery in Case 3 of this application.

[0127] like Figure 5 , Figure 6As shown, after the lithium-ion batteries of Case 1 and Case 2 are charged and discharged for cycles, there is no lithium deposition at the interface between the negative electrode and the separator, so there is no risk of accelerated attenuation caused by lithium deposition. This result is consistent with the result determined by the charging voltage platform value.

[0128] like Figure 7 As shown, after the lithium-ion battery of Case 3 was charged and discharged for a cycle, obvious lithium deposition occurred on the negative electrode surface and the diaphragm interface. Lithium deposition will cause the battery capacity to decay faster. This result is consistent with the result determined by the charging voltage platform value.

[0129] Therefore, it is possible to determine whether the lithium-ion battery will accelerate its decay based on the charging voltage platform change data corresponding to different cycle numbers.

[0130] However, in practical applications, the number of charge and discharge cycles of lithium-ion batteries may affect the judgment results. For example, the number of charge and discharge cycles of the battery is relatively small, and the number of cycles before and after is not much different (for example, 1 cycle and 100 cycles). At this time, the difference between the charging voltage platform value corresponding to the number of cycles after and the charging voltage platform value corresponding to the number of cycles before may not exceed the preset threshold, but the battery has accelerated attenuation caused by lithium precipitation in the later stage of the cycle. On the contrary, if the battery is charged and discharged for a large number of times, the difference between the number of cycles before and after is also large (for example, 1 cycle and 5000 cycles). At this time, although it can be more accurately identified that the battery may have the risk of accelerated attenuation caused by lithium precipitation in the later stage of the cycle, there may be problems of inefficiency caused by a large number of charge and discharge cycles, and a large amount of computing resources may be wasted.

[0131] Furthermore, considering that battery lithium plating is closely related to the increase in battery polarization during the charging process, it is also possible to identify whether the battery has the risk of accelerated attenuation and capacity diving caused by lithium plating in the later stage of the cycle through the voltage change of the phase transition.

[0132] For details, see the attached Figure 8 , Figure 8 FIG. 1 is a flow chart of the main steps of a method for identifying accelerated degradation of a lithium-ion battery according to another embodiment of the present application. Figure 8 As shown, the accelerated degradation identification method of a lithium-ion battery in the embodiment of the present application may further include the following steps S104 to S106 in addition to the above steps S101 to S103.

[0133] Step S104: performing differential processing on the voltage data and the capacity data to obtain a differential curve of capacity and voltage;

[0134] Specifically, mathematical software such as Matlab, Mathematica, or programming software such as Python, Java, etc. can be used to perform differential calculations on the voltage data and capacity data to obtain a differential curve of capacity and voltage. The differential curve can more keenly reflect the rate of change of the voltage as the capacity changes during the battery's charge and discharge process.

[0135] See attached Fig. 9 , Fig. 9 It is a schematic diagram of the relationship between voltage data and capacity data of a lithium-ion battery according to an embodiment of the present application.

[0136] like Fig. 9 As shown, the voltage data and capacity data of the whole battery, positive electrode LFP, and negative electrode C of a lithium iron phosphate battery during charging can be collected in real time to obtain Fig. 9 The relationship curve between voltage data and capacity data is shown.

[0137] Furthermore, we can Fig. 9 The relationship curve between the voltage data and capacity data of the full battery, positive electrode LFP, and negative electrode C shown is differentiated to obtain the differential curve of capacity and voltage.

[0138] See attached Fig.10 , Fig.10 FIG. 1 is a schematic diagram of a differential curve of capacity and voltage of a lithium-ion battery according to an embodiment of the present application. The ordinate is dV / dQ (derivative of voltage to capacity), and the abscissa is capacity. Fig.10 As shown, the dV / dQ curves of the full battery, positive electrode LFP, and negative electrode C vary with capacity.

[0139] Step S105: obtaining the phase change voltage value in the differential curve;

[0140] When the battery is charged, lithium ions are released from the positive electrode (lithium iron phosphate) and migrate to the negative electrode (graphite), and then embedded in the interlayer structure of graphite. As lithium ions are continuously embedded, the crystal structure of graphite changes accordingly. This process is called phase change. When the crystal structure of graphite changes, the voltage changes relatively quickly, resulting in significant fluctuations in the dV / dQ value. Fig.10 As shown in FIG. 1 , the peak value generated by the obvious fluctuation of dV / dQ is called the phase change peak. The voltage value corresponding to the phase change peak can be called the phase change voltage value.

[0141] Step S106: determining whether the lithium-ion battery will accelerate decay based on the phase change voltage value.

[0142] Specifically, lithium iron phosphate batteries are two-electrode systems, with only a positive electrode and a negative electrode. In this system, the voltage measured is the potential difference between the positive electrode and the negative electrode, that is, the voltage of the entire battery. Fig.10 As shown, the corresponding phase change peak of the whole battery is mainly caused by the deintercalation of lithium at the negative electrode of the battery. Therefore, by directly differentiating the voltage data and capacity data of the whole battery, it can be indicated whether the phase change voltage value of the negative electrode will change during the lithium intercalation process.

[0143] Therefore, in some implementations of step S106, a differential curve of capacity and voltage corresponding to different numbers of cycles may be obtained, and the full-battery phase change voltage values ​​corresponding to different numbers of cycles may be obtained based on the differential curve.

[0144] See attached Figures 11 to 13 , Fig.11 1 is a schematic diagram of the differential curve of capacity and voltage corresponding to different cycle numbers of the lithium-ion battery in Example 1 of the present application; Fig.12 1 is a schematic diagram of differential curves of capacity and voltage corresponding to different numbers of cycles of the lithium-ion battery in Example 2 of the present application; Fig.13 It is a schematic diagram of the differential curve of capacity and voltage corresponding to different cycle numbers of the lithium-ion battery in Example 3 of the present application.

[0145] like Figure 11-13 As shown, the ordinate is dQ / dV, and the abscissa is the voltage value. The phase change process of graphite between 3.35V and 3.4V can be used as a judgment standard, and the voltage value corresponding to the phase change peak can be observed to determine the change in the phase change voltage value of the whole battery.

[0146] Furthermore, it can be determined whether the full-battery phase change voltage value corresponding to the subsequent number of cycles is greater than the full-battery phase change voltage value corresponding to the previous number of cycles; if so, it is determined that the lithium-ion battery will accelerate decay; otherwise, it is determined that the lithium-ion battery will not accelerate decay.

[0147] like Fig.11 , Fig.12 As shown, when the lithium-ion batteries of Case 1 and Case 2 are charged and discharged, the voltage value corresponding to the phase change peak does not increase with the increase in the number of cycles, that is, the phase change voltage value of the whole battery corresponding to the later number of cycles is not greater than the phase change voltage value of the whole battery corresponding to the previous number of cycles. Therefore, it can be determined that the battery has no risk of accelerated attenuation caused by lithium plating in the later stage of the cycle. This result is consistent with the result determined by the charging voltage platform value.

[0148] like Fig.13 As shown, when the lithium-ion battery in Case 3 is charged and discharged, the voltage value corresponding to the phase change peak increases significantly with the increase in the number of cycles, that is, the phase change voltage value of the whole battery corresponding to the later number of cycles is greater than the phase change voltage value of the whole battery corresponding to the previous number of cycles. Therefore, it can be determined that the battery has the risk of accelerated attenuation caused by lithium plating in the later stage of the cycle. This result is consistent with the result determined by the charging voltage platform value.

[0149] Through the above implementation, it is possible to determine whether the lithium iron phosphate battery will accelerate decay based on the phase change voltage value of the whole battery.

[0150] In some other embodiments of step S106, for some lithium-ion batteries with three-electrode systems (including a working electrode, a reference electrode, and a counter electrode), such as ternary three-electrode batteries, lithium manganate three-electrode batteries, etc., the voltage of the negative electrode can be measured during the charge and discharge cycle. Therefore, it is also possible to determine whether the lithium-ion battery will accelerate decay based on the negative electrode phase change voltage value.

[0151] Specifically, after obtaining the differential curves of capacity and voltage corresponding to different numbers of cycles, the negative electrode phase change voltage values ​​corresponding to different numbers of cycles can be obtained based on the differential curves, and it can be determined whether the negative electrode phase change voltage value corresponding to the later number of cycles is greater than the negative electrode phase change voltage value corresponding to the previous number of cycles; if so, it is determined that the lithium-ion battery will accelerate decay; otherwise, it is determined that the lithium-ion battery will not accelerate decay.

[0152] Among them, regarding the specific process of the method for determining whether a lithium iron phosphate battery will accelerate decay based on the negative electrode phase change voltage value, please refer to the content described in the above-mentioned embodiment of determining whether a lithium iron phosphate battery will accelerate decay based on the phase change voltage value of the whole battery, which will not be repeated here.

[0153] The above is the description of step S106.

[0154] Furthermore, in order to fully verify the accuracy of the accelerated degradation identification method of the above-mentioned lithium-ion battery, the lithium-ion batteries of the above-mentioned three cases were subjected to continuous charge and discharge cycles, and the relationship curves between the battery state of health (SOH) and the number of cycles of the above-mentioned three cases were obtained.

[0155] See attached Figures 14 to 16 , Fig.14 1 is a schematic diagram of the relationship between the SOH and the number of cycles of the lithium-ion battery in Example 1 of the present application; Fig.15 1 is a graph showing the relationship between the SOH and the number of cycles of the lithium-ion battery in Example 2 of the present application; Fig.16 This is a diagram showing the relationship between the SOH and the number of cycles of the lithium-ion battery in Example 3 of the present application.

[0156] like Fig.14 , Fig.15 As shown, the lithium-ion batteries in Case 1 and Case 2 did not decay rapidly in the later stages of the cycle; Fig.16 As shown, the lithium-ion battery in Case 3 experienced accelerated decay in the later stage of the cycle, and this result is consistent with the result determined by the charging voltage platform value and the phase change voltage value. Therefore, it can be proved that the accelerated decay identification method of lithium-ion batteries provided in this application is accurate.

[0157] Through the above-mentioned accelerated attenuation identification method of lithium-ion batteries, the battery state is the same as the actual cycle, and the cycle data can be directly analyzed without additional testing or changing the cycle test conditions. It can accurately identify whether the lithium-ion battery will accelerate the attenuation result, which is convenient; lithium-ion batteries of different systems and different formulas can be analyzed, and the lithium plating / diving risks under the preset conditions can be obtained according to the different requirements / different working conditions of the battery. It is not affected by the size of the battery, is suitable for square shells and soft packs, and has universal applicability; there is no need to test the lithium plating critical point of the battery to be analyzed at the corresponding SOH in advance, but the result can be known as the cycle, which is timely.

[0158] The above is a further explanation of the accelerated decay identification method of the lithium-ion battery provided in the present application.

[0159] It should be pointed out that although the various steps in the above embodiments are described in a specific order, those skilled in the art can understand that in order to achieve the effect of the present application, different steps do not have to be executed in such an order. They can be executed simultaneously (in parallel) or in other orders. These changes are within the scope of protection of the present application.

[0160] Furthermore, the present application also provides a device for identifying accelerated decay of a lithium-ion battery.

[0161] See attached Fig.17 , Fig.17 FIG. 1 is a main structural block diagram of an accelerated decay identification device according to an embodiment of the present application. Fig.17 As shown, the accelerated decay identification device in the embodiment of the present application mainly includes a first acquisition module 1701, a second acquisition module 1702 and a judgment module 1703.

[0162] In some embodiments, the first acquisition module 1701 can be configured to acquire the voltage data and capacity data of the lithium-ion battery during the charging process when the lithium-ion battery is charged and discharged. The second acquisition module 1702 can be configured to acquire the charging voltage platform change data based on the voltage data and capacity data corresponding to different numbers of cycles. The judgment module 1703 can be configured to determine whether the lithium-ion battery will accelerate decay based on the charging voltage platform change data. In one embodiment, the description of the specific implementation function can be referred to steps S101 to S103.

[0163] Further, it should be understood that since the setting of each module is only for illustrating the functional units of the device of the present application, the physical devices corresponding to these modules may be the processor itself, or a part of the software in the processor, a part of the hardware, or a part of the combination of software and hardware. Therefore, the number of each module in the figure is only schematic.

[0164] It is understood by those skilled in the art that each module in the device can be adaptively split or merged. Such splitting or merging of specific modules will not cause the technical solution to deviate from the principle of the present application, and therefore, the technical solutions after splitting or merging will fall within the protection scope of the present application.

[0165] The above-mentioned accelerated decay identification device is used to perform Figure 1 and Figure 8 The embodiment of the accelerated decay identification method for lithium-ion batteries shown in the figure has similar technical principles, technical problems solved and technical effects produced. Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working process and related instructions of the accelerated decay identification device for lithium-ion batteries can refer to the contents described in the embodiment of the accelerated decay identification method for lithium-ion batteries, which will not be repeated here.

[0166] It is understood by those skilled in the art that all or part of the processes in the method for implementing the above-mentioned embodiment of the present application can also be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable storage medium may include: any entity or device, medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory, random access memory, electrical carrier signal, telecommunication signal and software distribution medium, etc. that can carry the computer program code.

[0167] Furthermore, the present application also provides an electronic device. Fig.18 , Fig.18 Schematic diagram of the main structure of an electronic device according to an embodiment of the present application. Fig.18 As shown, the electronic device in the embodiment of the present application mainly includes a processor 1801 and a memory 1802. The memory 1802 can be configured to store a program for executing the accelerated decay identification method of the lithium-ion battery of the above method embodiment, and the processor 1801 can be configured to execute the program in the memory 1802, which includes but is not limited to the program for executing the accelerated decay identification method of the lithium-ion battery of the above method embodiment. For ease of explanation, only the part related to the embodiment of the present application is shown. For specific technical details not disclosed, please refer to the method part of the embodiment of the present application.

[0168] In some possible implementations of the present application, the electronic device may include multiple processors 1801 and multiple memories 1802. The program for executing the accelerated decay identification method for lithium-ion batteries of the above method embodiment may be divided into multiple subprograms, and each subprogram may be loaded and run by the processor 1801 to execute different steps of the accelerated decay identification method for lithium-ion batteries of the above method embodiment. Specifically, each subprogram may be stored in different memories 1802, respectively, and each processor 1801 may be configured to execute the programs in one or more memories 1802 to jointly implement the accelerated decay identification method for lithium-ion batteries of the above method embodiment, that is, each processor 1801 executes different steps of the accelerated decay identification method for lithium-ion batteries of the above method embodiment, respectively, to jointly implement the accelerated decay identification method for lithium-ion batteries of the above method embodiment.

[0169] The multiple processors 1801 may be processors deployed on the same device. For example, the electronic device may be a high-performance device composed of multiple processors, and the multiple processors 1801 may be processors configured on the high-performance device. In addition, the multiple processors 1801 may also be processors deployed on different devices. For example, the electronic device may be a server cluster, and the multiple processors 1801 may be processors on different servers in the server cluster.

[0170] Furthermore, the present application also provides a computer-readable storage medium. In a computer-readable storage medium embodiment according to the present application, the computer-readable storage medium can be configured to store a program for executing the accelerated decay identification method of the lithium-ion battery of the above-mentioned method embodiment, and the program can be loaded and run by the processor to implement the above-mentioned accelerated decay identification method of the lithium-ion battery. For ease of explanation, only the parts related to the embodiment of the present application are shown. For specific technical details not disclosed, please refer to the method part of the embodiment of the present application. The computer-readable storage medium can be a memory device formed by various electronic devices. Optionally, the computer-readable storage medium in the embodiment of the present application is a non-temporary computer-readable storage medium.

[0171] It should be noted that the relevant user personal information that may be involved in the various embodiments of the present application is strictly in accordance with the requirements of laws and regulations, following the principles of legality, legitimacy and necessity, based on the reasonable purposes of business scenarios, to process the personal information that users actively provide during the use of products / services or generated due to the use of products / services, as well as the personal information obtained with the user's authorization.

[0172] This application attaches great importance to the security of user personal information and has taken reasonable and feasible security protection measures that meet industry standards to protect user information and prevent personal information from being accessed, disclosed, used, modified, damaged or lost without authorization.

[0173] So far, the technical solution of the present application has been described in conjunction with an embodiment shown in the accompanying drawings, but it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present application.

Claims

1. A method for identifying accelerated attenuation of a lithium-ion battery, characterized in that: The method comprises: When the lithium-ion battery is charged and discharged, the voltage data and capacity data during the charging process are obtained; Based on the voltage data and capacity data corresponding to different numbers of cycles, acquiring charging voltage platform change data; Whether the lithium-ion battery will accelerate decay is determined based on the charging voltage platform change data.

2. The method for identifying accelerated attenuation of a lithium-ion battery according to claim 1, characterized in that: The acquiring charging voltage platform change data based on the voltage data and capacity data corresponding to different numbers of cycles includes: Obtaining the relationship between the voltage data and the capacity data corresponding to the different numbers of cycles; Based on the relationship, the charging voltage platform values ​​corresponding to the different numbers of cycles are obtained; Based on the charging voltage platform values ​​corresponding to the different numbers of cycles, the charging voltage platform change data is obtained.

3. The method for identifying accelerated decay of a lithium-ion battery according to claim 2, characterized in that: The determining whether the lithium-ion battery will accelerate decay based on the charging voltage platform change data includes: Obtaining the difference between the charging voltage platform value corresponding to the subsequent cycle number and the charging voltage platform value corresponding to the previous cycle number; Determining whether the difference exceeds a preset threshold; If so, it is determined that the lithium-ion battery will decay at an accelerated rate; otherwise, it is determined that the lithium-ion battery will not decay at an accelerated rate.

4. The method for identifying accelerated attenuation of a lithium-ion battery according to claim 1, characterized in that: The method further comprises: Performing differential processing on the voltage data and the capacity data to obtain a differential curve of capacity and voltage; Obtaining a phase change voltage value in the differential curve; Whether the lithium-ion battery will accelerate degradation is determined based on the phase change voltage value.

5. The method for identifying accelerated attenuation of a lithium-ion battery according to claim 4, characterized in that: The determining whether the lithium-ion battery will accelerate decay based on the phase change voltage value comprises: Obtain the differential curves of capacity and voltage corresponding to different numbers of cycles; Obtaining full-battery phase change voltage values ​​corresponding to different cycle numbers based on the differential curve; Determine whether the full battery phase change voltage value corresponding to the subsequent cycle number is greater than the full battery phase change voltage value corresponding to the previous cycle number; If so, it is determined that the lithium-ion battery will decay at an accelerated rate; otherwise, it is determined that the lithium-ion battery will not decay at an accelerated rate.

6. The method for identifying accelerated decay of a lithium-ion battery according to claim 4, characterized in that: The determining whether the lithium-ion battery will accelerate decay based on the phase change voltage value further includes: Obtain the differential curves of capacity and voltage corresponding to different numbers of cycles; Obtaining negative electrode phase change voltage values ​​corresponding to different cycle numbers based on the differential curve; Determine whether the negative electrode phase change voltage value corresponding to the subsequent cycle number is greater than the negative electrode phase change voltage value corresponding to the previous cycle number; If so, it is determined that the lithium-ion battery will decay at an accelerated rate; otherwise, it is determined that the lithium-ion battery will not decay at an accelerated rate.

7. The method for identifying accelerated degradation of a lithium-ion battery according to any one of claims 1 to 6, characterized in that: The lithium-ion battery performs a charge and discharge cycle comprising: Controlling the lithium-ion battery to perform charge and discharge cycles under preset conditions; Wherein, the preset conditions include a preset charging current, a preset discharging current, a preset charging cut-off voltage and a preset discharging cut-off voltage.

8. A lithium-ion battery accelerated decay identification device, characterized in that: The device comprises: A first acquisition module, configured to acquire voltage data and capacity data of the lithium-ion battery during a charging process when the lithium-ion battery undergoes a charge and discharge cycle; A second acquisition module is configured to acquire charging voltage platform change data based on the voltage data and capacity data corresponding to different numbers of cycles; A judgment module is configured to determine whether the lithium-ion battery will accelerate decay based on the charging voltage platform change data.

9. An electronic device comprising a processor and a memory, wherein the memory is suitable for storing a plurality of program codes, wherein: The program code is suitable for being loaded and run by the processor to execute the accelerated degradation identification method of a lithium-ion battery according to any one of claims 1 to 7.

10. A computer-readable storage medium storing a plurality of program codes, characterized in that: The program code is suitable for being loaded and run by a processor to execute the accelerated degradation identification method for a lithium-ion battery according to any one of claims 1 to 7.

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