Online Detection Method, Device, Electronic Device and Storage Medium for Dead Lithium in Lithium Batteries

Abstract

An embodiment of the present application provides a method, device, electronic device, and storage medium for online detection of dead lithium in a lithium battery. The method includes: obtaining a plurality of battery parameters of the lithium battery to be analyzed under a preset state of charge within a preset period; obtaining a plurality of battery characteristic values according to the plurality of battery parameters; and determining whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values. Implementing the above embodiments can correctly identify whether dead lithium is generated in the lithium battery.

Description

Technical Field

[0001] The present application relates to the technical field of lithium batteries, and in particular to a method, device, electronic device and storage medium for online detection of dead lithium in lithium batteries. Background Art

[0002] Compared with the refueling speed of traditional fuel vehicles, new energy vehicles charge slowly, their performance weakens at low temperatures, and their safety deteriorates with battery aging and use under extreme conditions. The above technical pain points of new energy vehicles restrict the market penetration. The main reason why the pain points are difficult to overcome is the technical limitations of mass-produced lithium-ion power batteries. If they are charged at a high rate or under extreme conditions such as low temperature, lithium ions will not have time to embed normally into the negative electrode. They will combine with electrons on the surface of the negative electrode and precipitate in the form of metal, reducing the capacity of active lithium and even causing the risk of thermal runaway of the battery. However, one of the analyzed lithium can be reversed and embedded in the negative electrode with discharge and sufficient shelf time, which will not affect the battery life and safety. Another part of the loss of active lithium comes from the formation and thickening of the SEI film. Only a part of the irreversible lithium precipitation forms "dead lithium" with various shapes growing on the outside of the negative electrode. In addition to causing a reduction in battery capacity and damaging battery life, in severe cases it will cause a short circuit in the battery and cause thermal runaway.

[0003] At present, there are two types of lithium ionization diagnosis: destructive and non-destructive. Destructive testing requires disassembly of the battery cell, and after disassembly, the negative electrode plate is directly observed or qualitatively and quantitatively tested through optical electron microscopes, XRD, DSC, etc. The environment for disassembling modules and batteries has high requirements for water and oxygen, and oxidation is prone to occur after disassembly, which affects the accuracy of detection. In general, the cost is high and the difficulty is great. After disassembly, the possibility of restoring the entire module is small, and it can only be replaced; non-destructive lithium ionization detection methods mainly include voltage relaxation method, differential capacity method, etc., which do not require disassembly, are not destructive to the battery, and are not easily affected by external environmental humidity, but some specific dead lithium forms cannot be detected by a single non-destructive testing method, and most of these methods cannot distinguish whether the lithium ion is lithium carbonate and alkyl lithium carbonate that have generated SEI film, or dead lithium that has a greater impact on safety. Summary of the invention

[0004] In view of this, the purpose of the embodiments of the present application is to provide a method, device, electronic device and storage medium for online detection of dead lithium in a lithium battery, which can accurately detect whether dead lithium has occurred in a lithium battery.

[0005] In a first aspect, an embodiment of the present application provides a method for online detection of dead lithium in a lithium battery, comprising:

[0006] Acquire multiple battery parameters of the lithium battery to be analyzed at a preset state of charge within a preset period;

[0007] Obtain a plurality of battery characteristic values according to the plurality of battery parameters, where the plurality of battery characteristic values include: the change rate of the stable open-circuit voltage value, the change rate of the cyclic Coulomb efficiency, and the change rate of the change amount of the charged capacity;

[0008] Judge whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values.

[0009] In the above implementation process, different from the prior art, by obtaining a plurality of battery parameters and battery characteristic values and judging whether dead lithium is generated in the battery based on the plurality of battery parameters and battery characteristic values, the accuracy and robustness of the judgment on whether dead lithium is generated in the battery can be improved. At the same time, by using a plurality of parameters that can change significantly when dead lithium is generated for judgment, it is possible to correctly identify whether dead lithium is generated in the lithium battery. The above process does not have a complex iterative process and is applicable to online estimation of whether dead lithium is generated in the battery.

[0010] Further, the step of judging whether the lithium battery generates dead lithium according to the plurality of battery characteristic values includes:

[0011] Judge whether the sum of the plurality of battery characteristic values exceeds a preset threshold;

[0012] If so, determine that the lithium battery generates dead lithium.

[0013] In the above implementation process, using the sum of the plurality of battery characteristic values as the judgment basis reduces the probability of misjudgment due to errors, improves the judgment accuracy, and correctly distinguishes whether there is dead lithium in the battery and whether dead lithium is truly generated.

[0014] Further, the step of judging whether the lithium battery generates dead lithium according to the plurality of battery characteristic values includes:

[0015] Obtain the number of characteristic values of the battery characteristic values that exceed the preset threshold among the plurality of battery characteristic values;

[0016] Judge whether the lithium battery generates dead lithium according to the number of characteristic values.

[0017] In the above implementation process, using the number of battery characteristic values of the battery characteristic values that exceed the preset threshold among the plurality of battery characteristic values as the judgment basis reduces the probability of misjudgment due to errors, improves the judgment accuracy, and correctly distinguishes whether there is dead lithium in the battery and whether dead lithium is truly generated.

[0018] Further, the step of judging whether the lithium battery generates dead lithium according to the number of characteristic values includes:

[0019] If the number of characteristic values is 1, re-obtain the plurality of battery characteristic values after a first preset time;

[0020] Rejudge whether dead lithium is generated in the lithium battery according to the multiple battery characteristic values.

[0021] In the above implementation process, if the number of characteristic values is 1, it indicates that misjudgment may occur. Therefore, the battery is left standing for the first preset time and rejudged after the first preset time, which can reduce the probability of misjudgment.

[0022] Further, the step of judging whether dead lithium is generated in the lithium battery according to the number of characteristic values includes:

[0023] If the number of characteristic values is 2, re-acquire the multiple battery characteristic values after the second preset time;

[0024] Rejudge whether dead lithium is generated in the lithium battery according to the multiple battery characteristic values.

[0025] In the above implementation process, if the number of characteristic values is 2, it indicates that misjudgment may occur. Therefore, the battery is left standing for the second preset time and rejudged after the second preset time, which can reduce the probability of misjudgment.

[0026] Further, the step of judging whether dead lithium is generated in the lithium battery according to the number of characteristic values includes:

[0027] If the number of characteristic values is 3, determine that dead lithium is generated in the lithium battery.

[0028] In the above implementation process, if the number of characteristic values is 3 at this time, it can be determined that dead lithium is generated in the lithium battery.

[0029] Further, the step of judging whether dead lithium is generated in the lithium battery according to the multiple battery characteristic values includes: obtaining the weight of each preset battery characteristic value, multiplying each of the battery characteristic values by the weight of each battery characteristic value to obtain multiple multiplied battery characteristic values;

[0030] Obtain the sum of the multiple multiplied battery characteristic values;

[0031] Judge whether the sum of the multiple multiplied battery characteristic values exceeds a preset threshold;

[0032] If so, determine that dead lithium is generated in the lithium battery.

[0033] In a second aspect, an on-line detection device for dead lithium in a lithium battery provided by an embodiment of the present application includes:

[0034] An acquisition module, configured to acquire a plurality of battery parameters of a lithium battery to be analyzed under a preset state of charge within a preset period.

[0035] A battery characteristic value acquisition module, configured to acquire a plurality of battery characteristic values according to the plurality of battery parameters, where the plurality of battery characteristic values include: a stable open-circuit voltage value change rate, a cyclic Coulombic efficiency change rate, and a change rate of a change in charged capacity;

[0036] A judgment module, configured to judge whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values.

[0037] In the above implementation process, different from the prior art, by acquiring a plurality of battery parameters and battery characteristic values, and judging whether dead lithium is generated in the battery based on the plurality of battery parameters and battery characteristic values, the accuracy and robustness of the judgment on whether dead lithium is generated in the battery can be improved, so that it can correctly identify whether dead lithium is generated in the lithium battery.

[0038] In a third aspect, an electronic device provided by an embodiment of the present application includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, where when the processor executes the computer program, the steps of the method according to any one of the first aspect are implemented.

[0039] In a fourth aspect, a computer-readable storage medium provided by an embodiment of the present application has instructions stored thereon, and when the instructions are run on a computer, the computer is caused to execute the method according to any one of the first aspect.

[0040] Other features and advantages of the present application will be described in the subsequent description, or, some features and advantages can be inferred from the description or determined without doubt, or can be known by implementing the above technologies disclosed in the present application.

[0041] To make the above objects, features, and advantages of the present application more obvious and understandable, the following specific embodiments are given, and in conjunction with the accompanying drawings, the detailed description is as follows. Description of the Drawings

[0042] To more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required to be used in the embodiments of the present application. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained according to these drawings without creative efforts.

[0043] Figure 1 It is a schematic flowchart of the method for online detection of dead lithium in a lithium battery provided by an embodiment of the present application;

[0044] Figure 2 It is a schematic structural diagram of the device for online detection of dead lithium in a lithium battery provided by an embodiment of the present application;

[0045] Figure 3 Schematic diagram of the structure of the electronic device provided by the embodiment of the present application. Detailed implementation manners

[0046] Next, the technical solutions in the embodiments of the present application will be described with reference to the accompanying drawings in the embodiments of the present application.

[0047] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present application, the terms "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0048] Embodiment 1

[0049] Refer to Figure 1 , the embodiment of the present application provides a method for online detection of dead lithium in a lithium battery, including:

[0050] S1: Obtain a plurality of battery parameters of the lithium battery to be analyzed under a preset state of charge within a preset period;

[0051] In the above steps, the preset period is 20 to 110 cycle periods close to the detection. The preset state of charge is 35% to 75% of the full charge state of the lithium battery.

[0052] S2: Obtain a plurality of battery characteristic values according to the plurality of battery parameters, and the plurality of battery characteristic values include: the change rate of the stable open-circuit voltage value, the change rate of the cycle Coulomb efficiency, and the change rate of the change amount of the charged capacity;

[0053] S3: Determine whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values.

[0054] Preferably, the plurality of battery parameters are obtained under the same state of charge. If the plurality of battery parameters are not obtained under the same state of charge, estimation methods such as the least squares method and the unscented Kalman filter can be used for correction.

[0055] In the above implementation process, different from the prior art, by obtaining multiple battery parameters and battery characteristic values and judging whether dead lithium is generated in the battery based on the multiple battery parameters and battery characteristic values, the accuracy and robustness of judging whether dead lithium is generated in the battery can be improved, so that it is possible to correctly identify whether dead lithium is generated in the lithium battery. When dead lithium is generated, the change of a single battery characteristic value is not significant compared with that in other cases. Therefore, it is impossible to judge whether dead lithium is really generated in the battery based on a single characteristic value. By comprehensively considering multiple characteristic values, it is possible to accurately obtain whether dead lithium is generated in the battery. On this basis, by using multiple parameters that can change significantly when dead lithium is generated as the judgment basis, the accuracy of the judgment can be further improved. The above process does not have a complex iteration process and is applicable to online estimation of whether dead lithium is generated in the battery.

[0056] In S1 and S2, the battery parameters can be voltage, current, time, temperature and its initial capacity. Specifically, the battery characteristic value is the stable voltage value (EoC-OCV) after standing for t0 time after charging, the change amount of the charged capacity within a preset period, the battery characteristic value can be the change amount of EoC-OCV within a preset period (N-week cycle) and the differential value of the change amount of EoC-OCV within a preset period (N-week cycle) with respect to the number of cycles (or time), that is, the change rate of the stable open-circuit voltage value, the change amount of the battery capacity within a preset period and the differential value of the change amount of the battery capacity within a preset period with respect to time (or the number of cycles within a preset period), that is, the change rate of the charged capacity change amount, the change amount of the cyclic coulombic efficiency (CE) within a preset period and the differential value of the cyclic coulombic efficiency within a preset period (N-week cycle) with respect to the number of cycles (or time), that is, the change rate of the cyclic coulombic efficiency; since the occurrence of lithium side reactions will cause the CE to decrease, compared with capacity decay, it is possible to analyze trace lithium batteries with higher accuracy. When dead lithium occurs, the CE curve shows continuous fluctuations. Therefore, calculating the change amount of CE and its differential with respect to the number of cycles (or time) is incorporated into the strategy for trend normalization analysis.

[0057] In a possible implementation manner, S3 includes: judging whether the sum of multiple battery characteristic values exceeds a preset threshold; if so, determining that dead lithium is generated in the lithium battery.

[0058] It should be noted that after determining that dead lithium is generated in the lithium battery, it does not mean that dead lithium is definitely generated. In order to further determine whether dead lithium is generated, it can be considered to perform a two-way charge and discharge working condition test and then determine according to whether there has been an abusive working condition within a preset period.

[0059] In the above implementation process, using the sum of multiple battery characteristic values as the judgment basis reduces the probability of misjudgment due to errors, improves the judgment accuracy, and correctly distinguishes whether there is dead lithium in the battery and whether dead lithium is really generated.

[0060] In a possible implementation, S3 includes:

[0061] S31: Obtain the number of eigenvalue of the battery eigenvalues that exceed the preset threshold among multiple battery eigenvalues;

[0062] S32: Determine whether dead lithium is generated in the lithium battery according to the number of eigenvalues.

[0063] In the above implementation process, the number of battery eigenvalues of the battery eigenvalues that exceed the preset threshold among multiple battery eigenvalues is used as the judgment basis, reducing the probability of misjudgment due to errors, improving the judgment accuracy, and correctly distinguishing whether there is dead lithium in the battery and whether dead lithium is truly generated.

[0064] In a possible implementation, S32 includes: If the number of eigenvalues is 1, re-obtain multiple battery eigenvalues after the first preset time; re-determine whether dead lithium is generated in the lithium battery according to the multiple battery eigenvalues.

[0065] Exemplarily, the first preset time is a cycle times / t1, where 2 < a < 10, t1 > t0, and t0 is the standing time for obtaining the stable voltage value.

[0066] In the above implementation process, if the number of eigenvalues is 1, it indicates that misjudgment may occur. Therefore, the battery is left standing for the first preset time and re-judged after the first preset time, which can reduce the probability of misjudgment.

[0067] In a possible implementation, S32 includes: If the number of eigenvalues is 2, re-obtain multiple battery eigenvalues after the second preset time; re-determine whether dead lithium is generated in the lithium battery according to the multiple battery eigenvalues;

[0068] Exemplarily, the second preset time is b cycle times / t2, where b > a and t2 > t1.

[0069] In the above embodiments, a, b, t0, t1, and t2 are adjusted according to different battery material systems and specific formulations.

[0070] In the above implementation process, if the number of eigenvalues is 2, it indicates that misjudgment may occur. Therefore, the battery is left standing for the second preset time and re-judged after the second preset time, which can reduce the probability of misjudgment.

[0071] In a possible implementation, S32 includes: If the number of eigenvalues is 3, determine that dead lithium is generated in the lithium battery.

[0072] In the above implementation process, if the number of eigenvalues is 3 at this time, it can be determined that dead lithium is generated in the lithium battery.

[0073] In a possible implementation, S3 further includes: obtaining the weight of each preset battery characteristic value, multiplying each battery characteristic value by the weight of each battery characteristic value to obtain a plurality of multiplied battery characteristic values; obtaining the sum of the plurality of multiplied battery characteristic values; determining whether the sum of the plurality of multiplied battery characteristic values exceeds a preset threshold; if so, determining that dead lithium is generated in the lithium battery.

[0074] Embodiment 2

[0075] See Figure 2 , the embodiment of the present application provides an on-line dead lithium detection device for a lithium battery, including:

[0076] An acquisition module 1, configured to acquire a plurality of battery parameters of a to-be-analyzed lithium battery under a preset state of charge within a preset period, where the plurality of battery characteristic values include: the change rate of the stable open-circuit voltage value, the change rate of the cycle Coulomb efficiency, and the change rate of the change amount of the charge capacity;

[0077] A battery characteristic value acquisition module 2, configured to acquire a plurality of battery characteristic values according to the plurality of battery parameters;

[0078] A judgment module 3, configured to judge whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values.

[0079] In the above implementation process, different from the prior art, by acquiring a plurality of battery parameters and battery characteristic values and judging whether dead lithium is generated in the battery based on the plurality of battery parameters and battery characteristic values, the accuracy and robustness of the judgment on whether dead lithium is generated in the battery can be improved, so as to correctly identify whether dead lithium is generated in the lithium battery.

[0080] In a possible implementation, the judgment module 3 is further configured to judge whether the sum of the plurality of battery characteristic values exceeds a preset threshold, and if so, determine that dead lithium is generated in the lithium battery.

[0081] In a possible implementation, the judgment module 3 is further configured to obtain the number of characteristic values of the battery characteristic values that exceed the preset threshold among the plurality of battery characteristic values; judge whether dead lithium is generated in the lithium battery according to the number of characteristic values.

[0082] In a possible implementation, when the number of characteristic values is 1, the judgment module 3 is further configured to re-acquire a plurality of battery characteristic values after a first preset time;

[0083] Re-judge whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values.

[0084] In a possible implementation, when the number of characteristic values is 2, the judgment module 3 is further configured to re-acquire a plurality of battery characteristic values after a second preset time; re-judge whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values.

[0085] In a possible implementation, the determination module 3 is further configured to, when the number of eigenvalue is 3, re-acquire a plurality of battery eigenvalues after a second preset time; and re-determine whether dead lithium is generated in the lithium battery according to the plurality of battery eigenvalues.

[0086] In a possible implementation, the determination module 3 is further configured to obtain the sum of the multiplied battery eigenvalues; determine whether the sum of the multiplied battery eigenvalues exceeds a preset threshold; if so, determine that dead lithium is generated in the lithium battery.

[0087] This application also provides an electronic device. Please refer to Figure 3 , Figure 3 which is a structural block diagram of an electronic device provided in an embodiment of this application. The electronic device may include a processor 31, a communication interface 32, a memory 33, and at least one communication bus 34. Among them, the communication bus 34 is used to realize the direct connection and communication of these components. Among them, the communication interface 32 of the electronic device in the embodiment of this application is used to communicate with other node devices for signaling or data. The processor 31 may be an integrated circuit chip with signal processing capabilities.

[0088] The above-mentioned processor 31 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. It can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or the processor 31 may also be any conventional processor, etc.

[0089] The memory 33 may be, but is not limited to, a random access memory (RAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), etc. The memory 33 stores computer-readable instructions. When the computer-readable instructions are executed by the processor 31, the electronic device may execute the various steps involved in the above method embodiments.

[0090] Optionally, the electronic device may further include a storage controller and an input / output unit.

[0091] Each component of the memory 33, the storage controller, the processor 31, the peripheral interface, and the input / output unit is electrically connected directly or indirectly to each other to achieve data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses 34. The processor 31 is configured to execute an executable module stored in the memory 33, such as a software functional module or a computer program included in the electronic device.

[0092] The input / output unit is used to provide the user with the ability to create tasks and create an optional start time period or a preset execution time for the task to achieve interaction between the user and the server. The input / output unit can be, but is not limited to, a mouse, a keyboard, etc.

[0093] It can be understood that Figure 3 The structure shown is only illustrative, and the electronic device may further include more or fewer components than those shown Figure 3 in it, or have a different configuration from that shown Figure 3 in it. Figure 3 Each component shown in it can be implemented by hardware, software, or a combination thereof.

[0094] The embodiment of the present application also provides a computer-readable storage medium. Instructions are stored on the computer-readable storage medium. When the instructions are run on a computer, the computer program is executed by the processor to implement the method of the method embodiment. To avoid repetition, it will not be elaborated here.

[0095] In several embodiments provided by the present application, it should be understood that the disclosed device and method can also be implemented in other ways. The device embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architectures, functions, and operations of the device, method, and computer program product according to multiple embodiments of the present application. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code. A module, a program segment, or a part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order from that marked in the accompanying drawings. For example, two consecutive blocks can actually be executed substantially in parallel, and they can sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0096] In addition, in each embodiment of the present application, each functional module may be integrated together to form an independent part, or each module may exist alone, or two or more modules may be integrated to form an independent part.

[0097] If the function is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to enable a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in each embodiment of the present application. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs that can store program codes.

[0098] The above are only the embodiments of the present application and are not used to limit the protection scope of the present application. For those skilled in the art, the present application may have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application. It should be noted that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0099] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the present application, and all should be covered by the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

[0100] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the existence of additional identical elements in the process, method, article or device comprising the element.

Claims

1. An online detection method for dead lithium in a lithium battery, characterized in that Including: Obtain a plurality of battery parameters of the lithium battery to be analyzed under a preset state of charge within a preset period; Obtain a plurality of battery characteristic values according to the plurality of battery parameters, the plurality of battery characteristic values including: the change rate of the stable open-circuit voltage value, the change rate of the cyclic Coulomb efficiency, and the change rate of the change amount of the charged capacity; Judge whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values; The step of judging whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values includes: Judge whether the sum of the plurality of battery characteristic values exceeds a first preset threshold; If so, determine that dead lithium is generated in the lithium battery; The change rate of the stable open-circuit voltage value is the change amount of EoC-OCV within a preset period and the differential value of the change amount of EoC-OCV within a preset period with respect to the number of cycles or time; the change rate of the cyclic Coulomb efficiency is the change amount of the cyclic Coulomb efficiency within a preset period and the differential value of the cyclic Coulomb efficiency within a preset period with respect to the number of cycles or time; the change rate of the change amount of the charged capacity is the change amount of the battery capacity within a preset period and the differential of the change amount of the battery capacity within a preset period with respect to the number of cycles or time; the EoC-OCV is the stable voltage value after standing for a preset time after charging.

2. The online detection method for dead lithium in a lithium battery according to claim 1, wherein, The step of judging whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values includes: Obtain the number of characteristic values of the battery characteristic values that exceed a second preset threshold among the plurality of battery characteristic values; Judge whether dead lithium is generated in the lithium battery according to the number of characteristic values.

3. The online detection method for dead lithium in a lithium battery according to claim 2, characterized in that, The step of judging whether dead lithium is generated in the lithium battery according to the number of characteristic values includes: If the number of characteristic values is 1, re-obtain the plurality of battery characteristic values after a first preset time; Judge again whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values.

4. The method for online detection of dead lithium in a lithium battery according to claim 3, characterized in that, The step of judging whether dead lithium is generated in the lithium battery according to the number of characteristic values includes: If the number of characteristic values is 2, re-obtain the plurality of battery characteristic values after a second preset time; Judge again whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values.

5. The online detection method for dead lithium in a lithium battery according to claim 2, characterized in that, The step of judging whether dead lithium is generated in the lithium battery according to the number of characteristic values includes: If the number of characteristic values is 3, determine that dead lithium is generated in the lithium battery.

6. The online detection method for dead lithium in a lithium battery according to claim 1, characterized in that, The step of judging whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values includes: Obtain the weight of each preset battery characteristic value, multiply each of the battery characteristic values by the weight of each battery characteristic value to obtain a plurality of multiplied battery characteristic values; Obtain the sum of the plurality of multiplied battery characteristic values; Judge whether the sum of the plurality of multiplied battery characteristic values exceeds a preset threshold; If so, determine that dead lithium is generated in the lithium battery.

7. An on-line detection device for dead lithium in a lithium battery, characterized in that, Including: An acquisition module for acquiring a plurality of battery parameters of the lithium battery to be analyzed under a preset state of charge within a preset period; A battery characteristic value acquisition module for obtaining a plurality of battery characteristic values according to the plurality of battery parameters, the plurality of battery characteristic values including: the change rate of the stable open-circuit voltage value, the change rate of the cyclic Coulomb efficiency, and the change rate of the change amount of the charged capacity; A judgment module, configured to judge whether dead lithium is generated in the lithium battery according to the plurality of battery characteristic values; The judgment module is further configured to: judge whether the sum of the plurality of battery characteristic values exceeds a first preset threshold; if so, determine that dead lithium is generated in the lithium battery; The stable open-circuit voltage value change rate is the change amount of EoC-OCV within a preset period and the differential value of the change amount of EoC-OCV within a preset period with respect to the number of cycles or time; the cycle Coulomb efficiency change rate is the change amount of the cycle Coulomb efficiency within a preset period and the differential value of the cycle Coulomb efficiency within a preset period with respect to the number of cycles or time; the change rate of the change amount of the charged capacity is the change amount of the battery capacity within a preset period and the differential of the change amount of the battery capacity within a preset period with respect to the number of cycles or time; the EoC-OCV is the stable voltage value after standing for a preset time after charging.

8. An electronic device, characterized in that, Including: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the method according to any one of claims 1-6 are implemented.

9. A computer-readable storage medium, characterized in that, Instructions are stored on the computer-readable storage medium, and when the instructions are run on a computer, the computer is caused to execute the method according to any one of claims 1-6.

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